Merge branch 'main' into update-tor-0.4.8.19

* Add localizable strings in show commands view n refactor code to remove duplicate string declarations.

* Modify struct to enum in separate file to Models/CommandsInfo.

* Add corrections code in refactory and enum.

* Correct code in command enum and ContentView.

* Dedicated CommandSuggestionsView to extract code

* Simplify CommandInfo + minor optimization

* Fix preview

---------

Co-authored-by: islam <2553451+qalandarov@users.noreply.github.com>

.gitattributes

@@ -0,0 +1,20 @@
+# Prevent Github Languages stats skewing:
+
+# Binaries and assets
+**/*.xcframework/** linguist-vendored
+**/*.xcassets/** linguist-vendored
+
+# Generated files
+**/*.pbxproj linguist-generated
+**/*.storyboard linguist-generated
+Package.resolved linguist-generated
+
+# Downloaded CSVs
+relays/online_relays_gps.csv linguist-vendored
+
+# Docs
+**/*.md linguist-documentation
+
+# Configs
+Configs/*.xcconfig linguist-documentation
+**/*.plist linguist-documentation

.github/workflows/fetch_georelays.yml

@@ -0,0 +1,71 @@
+name: Fetch GeoRelays Data
+
+on:
+  schedule:
+    - cron: '0 6 * * 0'
+  workflow_dispatch:
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  update-relay-data:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          fetch-depth: 0
+
+      - name: Fetch GeoRelays
+        run: |
+          wget -q https://raw.githubusercontent.com/permissionlesstech/georelays/refs/heads/main/nostr_relays.csv
+          mv nostr_relays.csv ./relays/online_relays_gps.csv
+
+      - name: Configure git
+        run: |
+          git config user.email "action@github.com"
+          git config user.name "GitHub Action"
+
+      - name: Create update branch if changes
+        id: create_branch
+        run: |
+          # exit early if no changes
+          if git diff --quiet --relays/online_relays_gps.csv; then
+            echo "changed=false" >> $GITHUB_OUTPUT
+            exit 0
+          fi
+
+          # branch name with timestamp
+          BRANCH="update-georelays-$(date -u +%Y%m%dT%H%M%SZ)"
+          git checkout -b "$BRANCH"
+
+          git add relays/online_relays_gps.csv
+          git commit -m "Automated update of relay data - $(date -u --rfc-3339=seconds)"
+          echo "changed=true" >> $GITHUB_OUTPUT
+          echo "branch=$BRANCH" >> $GITHUB_OUTPUT
+
+      - name: Push branch
+        if: steps.create_branch.outputs.changed == 'true'
+        run: |
+          git push --set-upstream origin "${{ steps.create_branch.outputs.branch }}"
+
+      - name: Create pull request
+        if: steps.create_branch.outputs.changed == 'true'
+        uses: peter-evans/create-pull-request@v5
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          commit-message: Automated update of relay data
+          branch: ${{ steps.create_branch.outputs.branch }}
+          base: main
+          title: Automated update of relay data
+          body: |
+            This PR was created automatically by the scheduled workflow. It updates relays/online_relays_gps.csv from the GeoRelays source.
+          labels: automated, georelays
+
+      - name: No changes
+        if: steps.create_branch.outputs.changed != 'true'
+        run: echo "No changes to relays/online_relays_gps.csv"

.github/workflows/swift-tests.yml

@@ -0,0 +1,27 @@
+name: Build & Test
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  test:
+    name: Run Swift Tests
+    runs-on: macos-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v5
+
+      - name: Set up Swift
+        uses: swift-actions/setup-swift@v2
+
+      - name: Build the package
+        run: swift build
+
+      - name: Run Tests
+        run: swift test --parallel

.gitignore

@@ -5,8 +5,9 @@
 ## implementation plans
 plans/
 
-## User settings
-xcuserdata/
+## AI
+CLAUDE.md
+AGENTS.md
 
 ## compatibility with Xcode 8 and earlier (ignoring not required starting Xcode 9)
 *.xcscmblueprint
@@ -15,6 +16,7 @@ xcuserdata/
 ## compatibility with Xcode 3 and earlier (ignoring not required starting Xcode 4)
 build/
 DerivedData/
+.DerivedData/
 *.moved-aside
 *.pbxuser
 !default.pbxuser
@@ -52,7 +54,8 @@ iOSInjectionProject/
 
 ## Xcode project
 *.xcodeproj/project.xcworkspace/
-*.xcodeproj/xcshareddata/
+## Xcode User settings
+xcuserdata/
 
 ## Python
 __pycache__/
@@ -62,3 +65,17 @@ __pycache__/
 ## Temporary files
 *.tmp
 *.temp
+
+## Cache
+.cache/
+
+# Local build results
+.Result*/
+.Result*.xcresult/
+TestResult.xcresult/
+*.xcresult/
+build.log
+*.log
+
+# Local configs
+Local.xcconfig

BRING_THE_NOISE.md

@@ -37,7 +37,7 @@ This three-message pattern provides:
 #### NoiseEncryptionService
 The main service managing all Noise operations:
 ```swift
-class NoiseEncryptionService {
+final class NoiseEncryptionService {
     private let staticIdentityKey: Curve25519.KeyAgreement.PrivateKey
     private let sessionManager: NoiseSessionManager
     private let channelEncryption = NoiseChannelEncryption()
@@ -47,7 +47,7 @@ class NoiseEncryptionService {
 #### NoiseSession
 Individual session state for each peer:
 ```swift
-class NoiseSession {
+final class NoiseSession {
     private var handshakeState: NoiseHandshakeState?
     private var sendCipher: NoiseCipherState?
     private var receiveCipher: NoiseCipherState?
@@ -58,7 +58,7 @@ class NoiseSession {
 #### NoiseSessionManager
 Thread-safe session management:
 ```swift
-class NoiseSessionManager {
+final class NoiseSessionManager {
     private var sessions: [String: NoiseSession] = [:]
     private let sessionsQueue = DispatchQueue(label: "noise.sessions", attributes: .concurrent)
 }

Configs/Debug.xcconfig

@@ -0,0 +1,4 @@
+#include "Release.xcconfig"
+
+// Optional include of local configs
+#include? "Local.xcconfig"

Configs/Local.xcconfig.example

@@ -0,0 +1,5 @@
+// Your Apple Developer Team ID - https://stackoverflow.com/a/18727947
+DEVELOPMENT_TEAM = ABC123
+
+// Unique bundle id to be able to register and run locally
+PRODUCT_BUNDLE_IDENTIFIER = chat.bitchat.$(DEVELOPMENT_TEAM)

Configs/Release.xcconfig

@@ -0,0 +1,11 @@
+MARKETING_VERSION = 1.5.0
+CURRENT_PROJECT_VERSION = 1
+
+IPHONEOS_DEPLOYMENT_TARGET = 16.0
+MACOSX_DEPLOYMENT_TARGET = 13.0
+SWIFT_VERSION = 5.0
+
+DEVELOPMENT_TEAM = L3N5LHJD5Y
+CODE_SIGN_STYLE = Automatic
+
+PRODUCT_BUNDLE_IDENTIFIER = chat.bitchat

Justfile

@@ -14,16 +14,16 @@ default:
 # Check prerequisites
 check:
     @echo "Checking prerequisites..."
-    @command -v xcodegen >/dev/null 2>&1 || (echo "❌ XcodeGen not found. Install with: brew install xcodegen" && exit 1)
-    @command -v xcodebuild >/dev/null 2>&1 || (echo "❌ Xcode not found. Install Xcode from App Store" && exit 1)
-    @security find-identity -v -p codesigning | grep -q "Developer ID" || (echo "⚠️  No Developer ID found - code signing may fail" && exit 0)
+    @command -v xcodebuild >/dev/null 2>&1 || (echo "❌ xcodebuild not found. Install Xcode from App Store" && exit 1)
+    @xcode-select -p | grep -q "Xcode.app" || (echo "❌ Full Xcode required, not just command line tools. Install from App Store and run:\n   sudo xcode-select -s /Applications/Xcode.app/Contents/Developer" && exit 1)
+    @test -d "/Applications/Xcode.app" || (echo "❌ Xcode.app not found in Applications folder. Install from App Store" && exit 1)
+    @xcodebuild -version >/dev/null 2>&1 || (echo "❌ Xcode not properly configured. Try:\n   sudo xcode-select -s /Applications/Xcode.app/Contents/Developer" && exit 1)
+    @security find-identity -v -p codesigning | grep -q "Apple Development\|Developer ID" || (echo "⚠️  No Developer ID found - code signing may fail" && exit 0)
     @echo "✅ All prerequisites met"
 
 # Backup original files
 backup:
     @echo "Backing up original project configuration..."
-    @cp project.yml project.yml.backup 2>/dev/null || true
-    @# Backup other files that get modified by xcodegen
     @if [ -f bitchat.xcodeproj/project.pbxproj ]; then cp bitchat.xcodeproj/project.pbxproj bitchat.xcodeproj/project.pbxproj.backup; fi
     @if [ -f bitchat/Info.plist ]; then cp bitchat/Info.plist bitchat/Info.plist.backup; fi
 
@@ -44,20 +44,15 @@ patch-for-macos: backup
     @# Move iOS-specific files out of the way temporarily
     @if [ -f bitchat/LaunchScreen.storyboard ]; then mv bitchat/LaunchScreen.storyboard bitchat/LaunchScreen.storyboard.ios; fi
 
-# Generate Xcode project with patches
-generate: patch-for-macos
-    @echo "Generating Xcode project..."
-    @xcodegen generate
-
 # Build the macOS app
-build: check generate
+build: #check generate
     @echo "Building BitChat for macOS..."
-    @xcodebuild -project bitchat.xcodeproj -scheme "bitchat (macOS)" -configuration Debug CODE_SIGN_IDENTITY="" CODE_SIGNING_REQUIRED=NO CODE_SIGN_ENTITLEMENTS="" build
+    @xcodebuild -project bitchat.xcodeproj -scheme "bitchat_macOS" -configuration Debug CODE_SIGN_IDENTITY="" CODE_SIGNING_REQUIRED=NO CODE_SIGN_ENTITLEMENTS="" build
 
 # Run the macOS app
 run: build
     @echo "Launching BitChat..."
-    @find ~/Library/Developer/Xcode/DerivedData -name "bitchat.app" -path "*/Debug/*" | head -1 | xargs -I {} open "{}"
+    @find ~/Library/Developer/Xcode/DerivedData -name "bitchat.app" -path "*/Debug/*" -not -path "*/Index.noindex/*" | head -1 | xargs -I {} open "{}"
 
 # Clean build artifacts and restore original files
 clean: restore
@@ -75,10 +70,8 @@ clean: restore
 # Quick run without cleaning (for development)
 dev-run: check
     @echo "Quick development build..."
-    @if [ ! -f project.yml.backup ]; then just patch-for-macos; fi
-    @xcodegen generate
-    @xcodebuild -project bitchat.xcodeproj -scheme "bitchat (macOS)" -configuration Debug CODE_SIGN_IDENTITY="" CODE_SIGNING_REQUIRED=NO CODE_SIGN_ENTITLEMENTS="" build
-    @find ~/Library/Developer/Xcode/DerivedData -name "bitchat.app" -path "*/Debug/*" | head -1 | xargs -I {} open "{}"
+    @xcodebuild -project bitchat.xcodeproj -scheme "bitchat_macOS" -configuration Debug CODE_SIGN_IDENTITY="" CODE_SIGNING_REQUIRED=NO CODE_SIGN_ENTITLEMENTS="" build
+    @find ~/Library/Developer/Xcode/DerivedData -name "bitchat.app" -path "*/Debug/*" -not -path "*/Index.noindex/*" | head -1 | xargs -I {} open "{}"
 
 # Show app info
 info:
@@ -106,11 +99,9 @@ nuke:
     @echo "🧨 Nuclear clean - removing all build artifacts and backups..."
     @rm -rf ~/Library/Developer/Xcode/DerivedData/bitchat-* 2>/dev/null || true
     @rm -rf bitchat.xcodeproj 2>/dev/null || true
-    @rm -f project.yml.backup 2>/dev/null || true
-    @rm -f project-macos.yml 2>/dev/null || true
     @rm -f bitchat.xcodeproj/project.pbxproj.backup 2>/dev/null || true
     @rm -f bitchat/Info.plist.backup 2>/dev/null || true
     @# Restore iOS-specific files if they were moved
     @if [ -f bitchat/LaunchScreen.storyboard.ios ]; then mv bitchat/LaunchScreen.storyboard.ios bitchat/LaunchScreen.storyboard; fi
-    @git checkout -- project.yml bitchat.xcodeproj/project.pbxproj bitchat/Info.plist 2>/dev/null || echo "⚠️  Not a git repo or no changes to restore"
+    @git checkout bitchat.xcodeproj/project.pbxproj bitchat/Info.plist 2>/dev/null || echo "⚠️  Not a git repo or no changes to restore"
     @echo "✅ Nuclear clean complete"

Package.resolved

@@ -0,0 +1,14 @@
+{
+  "pins" : [
+    {
+      "identity" : "swift-secp256k1",
+      "kind" : "remoteSourceControl",
+      "location" : "https://github.com/21-DOT-DEV/swift-secp256k1",
+      "state" : {
+        "revision" : "8c62aba8a3011c9bcea232e5ee007fb0b34a15e2",
+        "version" : "0.21.1"
+      }
+    }
+  ],
+  "version" : 2
+}

Package.swift

@@ -4,6 +4,7 @@ import PackageDescription
 
 let package = Package(
     name: "bitchat",
+    defaultLocalization: "en",
     platforms: [
         .iOS(.v16),
         .macOS(.v13)
@@ -14,9 +15,19 @@ let package = Package(
             targets: ["bitchat"]
         ),
     ],
+    dependencies:[
+        .package(path: "localPackages/Tor"),
+        .package(path: "localPackages/BitLogger"),
+        .package(url: "https://github.com/21-DOT-DEV/swift-secp256k1", exact: "0.21.1")
+    ],
     targets: [
         .executableTarget(
             name: "bitchat",
+            dependencies: [
+                .product(name: "P256K", package: "swift-secp256k1"),
+                .product(name: "BitLogger", package: "BitLogger"),
+                .product(name: "Tor", package: "Tor")
+            ],
             path: "bitchat",
             exclude: [
                 "Info.plist",
@@ -24,7 +35,22 @@ let package = Package(
                 "bitchat.entitlements",
                 "bitchat-macOS.entitlements",
                 "LaunchScreen.storyboard"
+            ],
+            resources: [
+                .process("Localizable.xcstrings")
             ]
         ),
+        .testTarget(
+            name: "bitchatTests",
+            dependencies: ["bitchat"],
+            path: "bitchatTests",
+            exclude: [
+                "Info.plist",
+                "README.md"
+            ],
+            resources: [
+                .process("Localization")
+            ]
+        )
     ]
-)
+)

README.md

@@ -1,89 +1,125 @@
-<img height="300" alt="bitchat" src="https://github.com/user-attachments/assets/2660f828-49c7-444d-beca-d8b01854667a" />
+<img width="256" height="256" alt="icon_128x128@2x" src="https://github.com/user-attachments/assets/90133f83-b4f6-41c6-aab9-25d0859d2a47" />
 
 ## bitchat
 
-A decentralized peer-to-peer messaging app that works over Bluetooth mesh networks. No internet required, no servers, no phone numbers. It's the side-groupchat. 
+A decentralized peer-to-peer messaging app with dual transport architecture: local Bluetooth mesh networks for offline communication and internet-based Nostr protocol for global reach. No accounts, no phone numbers, no central servers. It's the side-groupchat.
 
 [bitchat.free](http://bitchat.free)
 
-> [!WARNING]
-> Private message and channel features have not received external security review and may contain vulnerabilities. Do not use for sensitive use cases, and do not rely on its security until it has been reviewed. Now uses the [Noise Protocol](http://www.noiseprotocol.org) for identity and encryption. Public local chat (the main feature) has no security concerns. 
+📲 [App Store](https://apps.apple.com/us/app/bitchat-mesh/id6748219622)
 
+> [!WARNING]
+> Private messages have not received external security review and may contain vulnerabilities. Do not use for sensitive use cases, and do not rely on its security until it has been reviewed. Now uses the [Noise Protocol](https://www.noiseprotocol.org) for identity and encryption. Public local chat (the main feature) has no security concerns.
 
 ## License
 
 This project is released into the public domain. See the [LICENSE](LICENSE) file for details.
 
-
 ## Features
 
+- **Dual Transport Architecture**: Bluetooth mesh for offline + Nostr protocol for internet-based messaging
+- **Location-Based Channels**: Geographic chat rooms using geohash coordinates over global Nostr relays
+- **Intelligent Message Routing**: Automatically chooses best transport (Bluetooth → Nostr fallback)
 - **Decentralized Mesh Network**: Automatic peer discovery and multi-hop message relay over Bluetooth LE
 - **Privacy First**: No accounts, no phone numbers, no persistent identifiers
-- **Cover Traffic**: Timing obfuscation and dummy messages for enhanced privacy
-- **Private Message End-to-End Encryption**: [Noise Protocol](http://noiseprotocol.org)
-- **Store & Forward**: Messages cached for offline peers and delivered when they reconnect
-- **IRC-Style Commands**: Familiar `/join`, `/msg`, `/who` style interface
+- **Private Message End-to-End Encryption**: [Noise Protocol](https://noiseprotocol.org) for mesh, NIP-17 for Nostr
+- **IRC-Style Commands**: Familiar `/slap`, `/msg`, `/who` style interface
 - **Universal App**: Native support for iOS and macOS
 - **Emergency Wipe**: Triple-tap to instantly clear all data
 - **Performance Optimizations**: LZ4 message compression, adaptive battery modes, and optimized networking
 
+## [Technical Architecture](https://deepwiki.com/permissionlesstech/bitchat)
 
-## Technical Architecture
+BitChat uses a **hybrid messaging architecture** with two complementary transport layers:
 
-### Binary Protocol
-bitchat uses an efficient binary protocol optimized for Bluetooth LE:
-- Compact packet format with 1-byte type field
-- TTL-based message routing (max 7 hops)
-- Automatic fragmentation for large messages
-- Message deduplication via unique IDs
+### Bluetooth Mesh Network (Offline)
 
-### Mesh Networking
-- Each device acts as both client and peripheral
-- Automatic peer discovery and connection management
-- Store-and-forward for offline message delivery
-- Adaptive duty cycling for battery optimization
+- **Local Communication**: Direct peer-to-peer within Bluetooth range
+- **Multi-hop Relay**: Messages route through nearby devices (max 7 hops)
+- **No Internet Required**: Works completely offline in disaster scenarios
+- **Noise Protocol Encryption**: End-to-end encryption with forward secrecy
+- **Binary Protocol**: Compact packet format optimized for Bluetooth LE constraints
+- **Automatic Discovery**: Peer discovery and connection management
+- **Adaptive Power**: Battery-optimized duty cycling
+
+### Nostr Protocol (Internet)
+
+- **Global Reach**: Connect with users worldwide via internet relays
+- **Location Channels**: Geographic chat rooms using geohash coordinates
+- **290+ Relay Network**: Distributed across the globe for reliability
+- **NIP-17 Encryption**: Gift-wrapped private messages for internet privacy
+- **Ephemeral Keys**: Fresh cryptographic identity per geohash area
+
+### Channel Types
+
+#### `mesh #bluetooth`
+
+- **Transport**: Bluetooth Low Energy mesh network
+- **Scope**: Local devices within multi-hop range
+- **Internet**: Not required
+- **Use Case**: Offline communication, protests, disasters, remote areas
+
+#### Location Channels (`block #dr5rsj7`, `neighborhood #dr5rs`, `country #dr`)
+
+- **Transport**: Nostr protocol over internet
+- **Scope**: Geographic areas defined by geohash precision
+  - `block` (7 chars): City block level
+  - `neighborhood` (6 chars): District/neighborhood
+  - `city` (5 chars): City level
+  - `province` (4 chars): State/province
+  - `region` (2 chars): Country/large region
+- **Internet**: Required (connects to Nostr relays)
+- **Use Case**: Location-based community chat, local events, regional discussions
+
+### Direct Message Routing
+
+Private messages use **intelligent transport selection**:
+
+1. **Bluetooth First** (preferred when available)
+
+   - Direct connection with established Noise session
+   - Fastest and most private option
+
+2. **Nostr Fallback** (when Bluetooth unavailable)
+
+   - Uses recipient's Nostr public key
+   - NIP-17 gift-wrapping for privacy
+   - Routes through global relay network
+
+3. **Smart Queuing** (when neither available)
+   - Messages queued until transport becomes available
+   - Automatic delivery when connection established
 
 For detailed protocol documentation, see the [Technical Whitepaper](WHITEPAPER.md).
 
-
 ## Setup
 
-### Option 1: Using XcodeGen (Recommended)
+### Option 1: Using Xcode
 
-1. Install XcodeGen if you haven't already:
-   ```bash
-   brew install xcodegen
-   ```
-
-2. Generate the Xcode project:
    ```bash
    cd bitchat
-   xcodegen generate
-   ```
-
-3. Open the generated project:
-   ```bash
    open bitchat.xcodeproj
    ```
 
-### Option 2: Using Swift Package Manager
+   To run on a device there're a few steps to prepare the code:
+   - Clone the local configs: `cp Configs/Local.xcconfig.example Configs/Local.xcconfig`
+   - Add your Developer Team ID into the newly created `Configs/Local.xcconfig`
+      - Bundle ID would be set to `chat.bitchat.<team_id>` (unless you set to something else)
+   - Entitlements need to be updated manually (TODO: Automate):
+      - Search and replace `group.chat.bitchat` with `group.<your_bundle_id>` (e.g. `group.chat.bitchat.ABC123`)
+
+### Option 2: Using `just`
 
-1. Open the project in Xcode:
    ```bash
-   cd bitchat
-   open Package.swift
+   brew install just
    ```
 
-2. Select your target device and run
-
-### Option 3: Manual Xcode Project
-
-1. Open Xcode and create a new iOS/macOS App
-2. Copy all Swift files from the `bitchat` directory into your project
-3. Update Info.plist with Bluetooth permissions
-4. Set deployment target to iOS 16.0 / macOS 13.0
-
-### Option 4: just
-
-Want to try this on macos: `just run` will set it up and run from source. 
+Want to try this on macos: `just run` will set it up and run from source.
 Run `just clean` afterwards to restore things to original state for mobile app building and development.
+
+## Localization
+
+- Base app resources live under `bitchat/Localization/Base.lproj/`. Add new copy to `Localizable.strings` and plural rules to `Localizable.stringsdict`.
+- Share extension strings are separate in `bitchatShareExtension/Localization/Base.lproj/Localizable.strings`.
+- Prefer keys that describe intent (`app_info.features.offline.title`) and reuse existing ones where possible.
+- Run `xcodebuild -project bitchat.xcodeproj -scheme "bitchat (macOS)" -configuration Debug CODE_SIGNING_ALLOWED=NO build` to compile-check any localization updates.

WHITEPAPER.md

@@ -1,6 +1,6 @@
 # BitChat Protocol Whitepaper
 
-**Version 1.0**
+**Version 1.1**
 
 **Date: July 25, 2025**
 
@@ -98,7 +98,7 @@ While the Noise handshake cryptographically authenticates a peer's key, it doesn
 ### 4.2. Favorites and Blocking
 
 To improve the user experience and provide control over interactions, the protocol supports:
-*   **Favorites:** Users can mark trusted or frequently contacted peers as "favorites." This is a local designation that can be used by the application to prioritize notifications or display peers more prominently.
+*   **Favorites:** Users can mark trusted or frequently contacted peers as "favorites". This is a local designation that can be used by the application to prioritize notifications or display peers more prominently.
 *   **Blocking:** Users can block peers. When a peer is blocked, the application will discard any incoming packets from that peer's fingerprint at the earliest possible stage, effectively silencing them without notifying the blocked peer.
 
 ---
@@ -184,6 +184,28 @@ To minimize bandwidth, `BitchatPacket`s are serialized into a compact binary for
 
 **Padding:** All packets are padded to the next standard block size (256, 512, 1024, or 2048 bytes) using a PKCS#7-style scheme to obscure the true message length from network observers.
 
+```mermaid
+---
+config:
+  theme: dark
+---
+---
+title: "BitchatPacket"
+---
+packet
++8: "Version"
++8: "Type"
++8: "TTL"
++64: "Timestamp"
++8: "Flags"
++16: "Payload Length"
++64: "Sender ID"
++64: "Recipient ID (optional)"
++48: "Payload (variable)"
++64: "Signature (optional)"
+```
+_A representation of the sizes of the fields in `BitchatPacket`_
+
 ### 6.2. Application Message Format (`BitchatMessage`)
 
 For packets of type `message`, the payload is a binary-serialized `BitchatMessage` containing the chat content.
@@ -198,6 +220,25 @@ For packets of type `message`, the payload is a binary-serialized `BitchatMessag
 | Original Sender     | 1 + len (opt)| Nickname of the original sender if the message is a relay.               |
 | Recipient Nickname  | 1 + len (opt)| Nickname of the recipient for private messages.                          |
 
+```mermaid
+---
+config:
+  theme: dark
+---
+---
+title: "BitchatMessage"
+---
+packet
++8: "Flags"
++64: "Timestamp"
++24: "ID (variable)"
++32: "Sender (variable)"
++32: "Content (variable)"
++32: "Original Sender (variable) (optional)"
++32: "Recipient Nickname (variable) (optional)"
+```
+_A representation of the sizes of the fields in `BitchatMessage`_
+
 ---
 
 ## 7. Message Routing and Propagation
@@ -215,7 +256,7 @@ To send messages to peers that are not directly connected, BitChat employs a "fl
 The logic is as follows:
 
 1.  A peer receives a packet.
-2.  It checks the Bloom filter to see if the packet's ID has likely been seen before. If so, the packet is discarded. Bloom filters can have false positives (though they are rare), but they guarantee no false negatives. This means a new packet will never be accidentally discarded.
+2.  It checks the Bloom filter to see if the packet's ID has likely been seen before. If so, the packet is discarded. Bloom filters can have false positives (though they are rare), but they guarantee no false negatives. This means that while some packets may be incorrectly discarded due to false positives, the gossip protocol's redundancy ensures these packets will eventually be received through subsequent exchanges with other peers.
 3.  If the packet is new, its ID is added to the Bloom filter.
 4.  The peer decrements the packet's Time-To-Live (TTL) field.
 5.  If the TTL is greater than zero, the peer re-broadcasts the packet to all of its connected peers, *except* for the peer from which it received the packet.
@@ -265,4 +306,4 @@ Receiving peers collect all fragments and reassemble them in the correct order b
 
 ## 9. Conclusion
 
-The BitChat Protocol provides a robust and secure foundation for decentralized, peer-to-peer communication. By layering a flexible application protocol on top of the well-regarded Noise Protocol Framework, it achieves strong confidentiality, authentication, and forward secrecy. The use of a compact binary format and thoughtful security considerations like rate limiting and traffic analysis resistance make it suitable for use in challenging network environments.
+The BitChat Protocol provides a robust and secure foundation for decentralized, peer-to-peer communication. By layering a flexible application protocol on top of the well-regarded Noise Protocol Framework, it achieves strong confidentiality, authentication, and forward secrecy. The use of a compact binary format and thoughtful security considerations like rate limiting and traffic analysis resistance make it suitable for use in challenging network environments.

bitchat.xcodeproj/xcshareddata/xcschemes/bitchat (iOS).xcscheme

@@ -0,0 +1,131 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "1640"
+   version = "1.3">
+   <BuildAction
+      parallelizeBuildables = "YES"
+      buildImplicitDependencies = "YES">
+      <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "57CA17A36A2532A6CFF367BB"
+               BuildableName = "bitchatShareExtension.appex"
+               BlueprintName = "bitchatShareExtension"
+               ReferencedContainer = "container:bitchat.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "AF077EA0474EDEDE2C72716C"
+               BuildableName = "bitchat.app"
+               BlueprintName = "bitchat_iOS"
+               ReferencedContainer = "container:bitchat.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+      </BuildActionEntries>
+   </BuildAction>
+   <TestAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      codeCoverageEnabled = "YES"
+      onlyGenerateCoverageForSpecifiedTargets = "YES">
+      <MacroExpansion>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "AF077EA0474EDEDE2C72716C"
+            BuildableName = "bitchat.app"
+            BlueprintName = "bitchat_iOS"
+            ReferencedContainer = "container:bitchat.xcodeproj">
+         </BuildableReference>
+      </MacroExpansion>
+      <CodeCoverageTargets>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "AF077EA0474EDEDE2C72716C"
+            BuildableName = "bitchat.app"
+            BlueprintName = "bitchat_iOS"
+            ReferencedContainer = "container:bitchat.xcodeproj">
+         </BuildableReference>
+      </CodeCoverageTargets>
+      <Testables>
+         <TestableReference
+            skipped = "NO"
+            parallelizable = "YES"
+            testExecutionOrdering = "random">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "6CB97DF2EA57234CB3E563B8"
+               BuildableName = "bitchatTests_iOS.xctest"
+               BlueprintName = "bitchatTests_iOS"
+               ReferencedContainer = "container:bitchat.xcodeproj">
+            </BuildableReference>
+         </TestableReference>
+      </Testables>
+   </TestAction>
+   <LaunchAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      launchStyle = "0"
+      useCustomWorkingDirectory = "NO"
+      ignoresPersistentStateOnLaunch = "NO"
+      debugDocumentVersioning = "YES"
+      debugServiceExtension = "internal"
+      allowLocationSimulation = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "AF077EA0474EDEDE2C72716C"
+            BuildableName = "bitchat.app"
+            BlueprintName = "bitchat_iOS"
+            ReferencedContainer = "container:bitchat.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+      <EnvironmentVariables>
+         <EnvironmentVariable
+            key = "BITCHAT_LOG_LEVEL"
+            value = "debug"
+            isEnabled = "YES">
+         </EnvironmentVariable>
+      </EnvironmentVariables>
+   </LaunchAction>
+   <ProfileAction
+      buildConfiguration = "Release"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      savedToolIdentifier = ""
+      useCustomWorkingDirectory = "NO"
+      debugDocumentVersioning = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "AF077EA0474EDEDE2C72716C"
+            BuildableName = "bitchat.app"
+            BlueprintName = "bitchat_iOS"
+            ReferencedContainer = "container:bitchat.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+   </ProfileAction>
+   <AnalyzeAction
+      buildConfiguration = "Debug">
+   </AnalyzeAction>
+   <ArchiveAction
+      buildConfiguration = "Release"
+      revealArchiveInOrganizer = "YES">
+   </ArchiveAction>
+</Scheme>

bitchat.xcodeproj/xcshareddata/xcschemes/bitchat (macOS).xcscheme

@@ -0,0 +1,105 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "1640"
+   version = "1.3">
+   <BuildAction
+      parallelizeBuildables = "YES"
+      buildImplicitDependencies = "YES">
+      <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "0576A29205865664C0937536"
+               BuildableName = "bitchat.app"
+               BlueprintName = "bitchat_macOS"
+               ReferencedContainer = "container:bitchat.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+      </BuildActionEntries>
+   </BuildAction>
+   <TestAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      shouldUseLaunchSchemeArgsEnv = "YES">
+      <MacroExpansion>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "0576A29205865664C0937536"
+            BuildableName = "bitchat.app"
+            BlueprintName = "bitchat_macOS"
+            ReferencedContainer = "container:bitchat.xcodeproj">
+         </BuildableReference>
+      </MacroExpansion>
+      <Testables>
+         <TestableReference
+            skipped = "NO"
+            parallelizable = "NO">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "47FF23248747DD7CB666CB91"
+               BuildableName = "bitchatTests_macOS.xctest"
+               BlueprintName = "bitchatTests_macOS"
+               ReferencedContainer = "container:bitchat.xcodeproj">
+            </BuildableReference>
+         </TestableReference>
+      </Testables>
+   </TestAction>
+   <LaunchAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      launchStyle = "0"
+      useCustomWorkingDirectory = "NO"
+      ignoresPersistentStateOnLaunch = "NO"
+      debugDocumentVersioning = "YES"
+      debugServiceExtension = "internal"
+      allowLocationSimulation = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "0576A29205865664C0937536"
+            BuildableName = "bitchat.app"
+            BlueprintName = "bitchat_macOS"
+            ReferencedContainer = "container:bitchat.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+      <EnvironmentVariables>
+         <EnvironmentVariable
+            key = "BITCHAT_LOG_LEVEL"
+            value = "debug"
+            isEnabled = "YES">
+         </EnvironmentVariable>
+      </EnvironmentVariables>
+   </LaunchAction>
+   <ProfileAction
+      buildConfiguration = "Release"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      savedToolIdentifier = ""
+      useCustomWorkingDirectory = "NO"
+      debugDocumentVersioning = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "0576A29205865664C0937536"
+            BuildableName = "bitchat.app"
+            BlueprintName = "bitchat_macOS"
+            ReferencedContainer = "container:bitchat.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+   </ProfileAction>
+   <AnalyzeAction
+      buildConfiguration = "Debug">
+   </AnalyzeAction>
+   <ArchiveAction
+      buildConfiguration = "Release"
+      revealArchiveInOrganizer = "YES">
+   </ArchiveAction>
+</Scheme>

bitchat/Assets.xcassets/AppIcon.appiconset/Contents.json

@@ -1,111 +1,9 @@
 {
   "images" : [
-    {
-      "filename" : "icon_20x20@2x.png",
-      "idiom" : "iphone",
-      "scale" : "2x",
-      "size" : "20x20"
-    },
-    {
-      "filename" : "icon_20x20@3x.png",
-      "idiom" : "iphone",
-      "scale" : "3x",
-      "size" : "20x20"
-    },
-    {
-      "filename" : "icon_29x29@2x.png",
-      "idiom" : "iphone",
-      "scale" : "2x",
-      "size" : "29x29"
-    },
-    {
-      "filename" : "icon_29x29@3x.png",
-      "idiom" : "iphone",
-      "scale" : "3x",
-      "size" : "29x29"
-    },
-    {
-      "filename" : "icon_40x40@2x.png",
-      "idiom" : "iphone",
-      "scale" : "2x",
-      "size" : "40x40"
-    },
-    {
-      "filename" : "icon_40x40@3x.png",
-      "idiom" : "iphone",
-      "scale" : "3x",
-      "size" : "40x40"
-    },
-    {
-      "filename" : "icon_60x60@2x.png",
-      "idiom" : "iphone",
-      "scale" : "2x",
-      "size" : "60x60"
-    },
-    {
-      "filename" : "icon_60x60@3x.png",
-      "idiom" : "iphone",
-      "scale" : "3x",
-      "size" : "60x60"
-    },
-    {
-      "filename" : "icon_20x20.png",
-      "idiom" : "ipad",
-      "scale" : "1x",
-      "size" : "20x20"
-    },
-    {
-      "filename" : "icon_20x20@2x.png",
-      "idiom" : "ipad",
-      "scale" : "2x",
-      "size" : "20x20"
-    },
-    {
-      "filename" : "icon_29x29.png",
-      "idiom" : "ipad",
-      "scale" : "1x",
-      "size" : "29x29"
-    },
-    {
-      "filename" : "icon_29x29@2x.png",
-      "idiom" : "ipad",
-      "scale" : "2x",
-      "size" : "29x29"
-    },
-    {
-      "filename" : "icon_40x40.png",
-      "idiom" : "ipad",
-      "scale" : "1x",
-      "size" : "40x40"
-    },
-    {
-      "filename" : "icon_40x40@2x.png",
-      "idiom" : "ipad",
-      "scale" : "2x",
-      "size" : "40x40"
-    },
-    {
-      "filename" : "icon_76x76.png",
-      "idiom" : "ipad",
-      "scale" : "1x",
-      "size" : "76x76"
-    },
-    {
-      "filename" : "icon_76x76@2x.png",
-      "idiom" : "ipad",
-      "scale" : "2x",
-      "size" : "76x76"
-    },
-    {
-      "filename" : "icon_83.5x83.5@2x.png",
-      "idiom" : "ipad",
-      "scale" : "2x",
-      "size" : "83.5x83.5"
-    },
     {
       "filename" : "icon_1024x1024.png",
-      "idiom" : "ios-marketing",
-      "scale" : "1x",
+      "idiom" : "universal",
+      "platform" : "ios",
       "size" : "1024x1024"
     },
     {

bitchat/Assets.xcassets/AppIconDebug.appiconset/Contents.json

@@ -0,0 +1,36 @@
+{
+  "images" : [
+    {
+      "filename" : "image-1024.png",
+      "idiom" : "universal",
+      "platform" : "ios",
+      "size" : "1024x1024"
+    },
+    {
+      "appearances" : [
+        {
+          "appearance" : "luminosity",
+          "value" : "dark"
+        }
+      ],
+      "idiom" : "universal",
+      "platform" : "ios",
+      "size" : "1024x1024"
+    },
+    {
+      "appearances" : [
+        {
+          "appearance" : "luminosity",
+          "value" : "tinted"
+        }
+      ],
+      "idiom" : "universal",
+      "platform" : "ios",
+      "size" : "1024x1024"
+    }
+  ],
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

bitchat/Assets.xcassets/Contents.json

@@ -3,4 +3,4 @@
     "author" : "xcode",
     "version" : 1
   }
-}
+}

bitchat/BitchatApp.swift

@@ -6,20 +6,42 @@
 // For more information, see <https://unlicense.org>
 //
 
+import Tor
 import SwiftUI
 import UserNotifications
 
 @main
 struct BitchatApp: App {
-    @StateObject private var chatViewModel = ChatViewModel()
+    static let bundleID = Bundle.main.bundleIdentifier ?? "chat.bitchat"
+    static let groupID = "group.\(bundleID)"
+    
+    @StateObject private var chatViewModel: ChatViewModel
     #if os(iOS)
+    @Environment(\.scenePhase) var scenePhase
     @UIApplicationDelegateAdaptor(AppDelegate.self) var appDelegate
+    // Skip the very first .active-triggered Tor restart on cold launch
+    @State private var didHandleInitialActive: Bool = false
+    @State private var didEnterBackground: Bool = false
     #elseif os(macOS)
     @NSApplicationDelegateAdaptor(MacAppDelegate.self) var appDelegate
     #endif
     
+    private let idBridge = NostrIdentityBridge()
+    
     init() {
+        let keychain = KeychainManager()
+        let idBridge = self.idBridge
+        _chatViewModel = StateObject(
+            wrappedValue: ChatViewModel(
+                keychain: keychain,
+                idBridge: idBridge,
+                identityManager: SecureIdentityStateManager(keychain)
+            )
+        )
+        
         UNUserNotificationCenter.current().delegate = NotificationDelegate.shared
+        // Warm up georelay directory and refresh if stale (once/day)
+        GeoRelayDirectory.shared.prefetchIfNeeded()
     }
     
     var body: some Scene {
@@ -28,11 +50,18 @@ struct BitchatApp: App {
                 .environmentObject(chatViewModel)
                 .onAppear {
                     NotificationDelegate.shared.chatViewModel = chatViewModel
-                    #if os(iOS)
+                    // Inject live Noise service into VerificationService to avoid creating new BLE instances
+                    VerificationService.shared.configure(with: chatViewModel.meshService.getNoiseService())
+                    // Prewarm Nostr identity and QR to make first VERIFY sheet fast
+                    DispatchQueue.global(qos: .utility).async {
+                        let npub = try? idBridge.getCurrentNostrIdentity()?.npub
+                        _ = VerificationService.shared.buildMyQRString(nickname: chatViewModel.nickname, npub: npub)
+                    }
+
                     appDelegate.chatViewModel = chatViewModel
-                    #elseif os(macOS)
-                    appDelegate.chatViewModel = chatViewModel
-                    #endif
+
+                    // Initialize network activation policy; will start Tor/Nostr only when allowed
+                    NetworkActivationService.shared.start()
                     // Check for shared content
                     checkForSharedContent()
                 }
@@ -40,10 +69,60 @@ struct BitchatApp: App {
                     handleURL(url)
                 }
                 #if os(iOS)
+                .onChange(of: scenePhase) { newPhase in
+                    switch newPhase {
+                    case .background:
+                        // Keep BLE mesh running in background; BLEService adapts scanning automatically
+                        // Always send Tor to dormant on background for a clean restart later.
+                        TorManager.shared.setAppForeground(false)
+                        TorManager.shared.goDormantOnBackground()
+                        // Stop geohash sampling while backgrounded
+                        Task { @MainActor in
+                            chatViewModel.endGeohashSampling()
+                        }
+                        // Proactively disconnect Nostr to avoid spurious socket errors while Tor is down
+                        NostrRelayManager.shared.disconnect()
+                        didEnterBackground = true
+                    case .active:
+                        // Restart services when becoming active
+                        chatViewModel.meshService.startServices()
+                        TorManager.shared.setAppForeground(true)
+                        // On initial cold launch, Tor was just started in onAppear.
+                        // Skip the deterministic restart the first time we become active.
+                        if didHandleInitialActive && didEnterBackground {
+                            if TorManager.shared.isAutoStartAllowed() && !TorManager.shared.isReady {
+                                TorManager.shared.ensureRunningOnForeground()
+                            }
+                        } else {
+                            didHandleInitialActive = true
+                        }
+                        didEnterBackground = false
+                        if TorManager.shared.isAutoStartAllowed() {
+                            Task.detached {
+                                let _ = await TorManager.shared.awaitReady(timeout: 60)
+                                await MainActor.run {
+                                    // Rebuild proxied sessions to bind to the live Tor after readiness
+                                    TorURLSession.shared.rebuild()
+                                    // Reconnect Nostr via fresh sessions; will gate until Tor 100%
+                                    NostrRelayManager.shared.resetAllConnections()
+                                }
+                            }
+                        }
+                        checkForSharedContent()
+                    case .inactive:
+                        break
+                    @unknown default:
+                        break
+                    }
+                }
                 .onReceive(NotificationCenter.default.publisher(for: UIApplication.didBecomeActiveNotification)) { _ in
                     // Check for shared content when app becomes active
                     checkForSharedContent()
                 }
+                #elseif os(macOS)
+                .onReceive(NotificationCenter.default.publisher(for: NSApplication.didBecomeActiveNotification)) { _ in
+                    // App became active
+                }
                 #endif
         }
         #if os(macOS)
@@ -61,7 +140,7 @@ struct BitchatApp: App {
     
     private func checkForSharedContent() {
         // Check app group for shared content from extension
-        guard let userDefaults = UserDefaults(suiteName: "group.chat.bitchat") else {
+        guard let userDefaults = UserDefaults(suiteName: BitchatApp.groupID) else {
             return
         }
         
@@ -70,30 +149,18 @@ struct BitchatApp: App {
             return
         }
         
-        // Only process if shared within last 30 seconds
-        if Date().timeIntervalSince(sharedDate) < 30 {
+        // Only process if shared within configured window
+        if Date().timeIntervalSince(sharedDate) < TransportConfig.uiShareAcceptWindowSeconds {
             let contentType = userDefaults.string(forKey: "sharedContentType") ?? "text"
             
             // Clear the shared content
             userDefaults.removeObject(forKey: "sharedContent")
             userDefaults.removeObject(forKey: "sharedContentType")
             userDefaults.removeObject(forKey: "sharedContentDate")
-            userDefaults.synchronize()
+            // No need to force synchronize here
             
-            // Show notification about shared content
+            // Send the shared content immediately on the main queue
             DispatchQueue.main.async {
-                // Add system message about sharing
-                let systemMessage = BitchatMessage(
-                    sender: "system",
-                    content: "preparing to share \(contentType)...",
-                    timestamp: Date(),
-                    isRelay: false
-                )
-                self.chatViewModel.messages.append(systemMessage)
-            }
-            
-            // Send the shared content after a short delay
-            DispatchQueue.main.asyncAfter(deadline: .now() + 1.0) {
                 if contentType == "url" {
                     // Try to parse as JSON first
                     if let data = sharedContent.data(using: .utf8),
@@ -114,19 +181,23 @@ struct BitchatApp: App {
 }
 
 #if os(iOS)
-class AppDelegate: NSObject, UIApplicationDelegate {
+final class AppDelegate: NSObject, UIApplicationDelegate {
     weak var chatViewModel: ChatViewModel?
     
     func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey : Any]? = nil) -> Bool {
         return true
     }
+    
+    func applicationWillTerminate(_ application: UIApplication) {
+        chatViewModel?.applicationWillTerminate()
+    }
 }
 #endif
 
 #if os(macOS)
 import AppKit
 
-class MacAppDelegate: NSObject, NSApplicationDelegate {
+final class MacAppDelegate: NSObject, NSApplicationDelegate {
     weak var chatViewModel: ChatViewModel?
     
     func applicationWillTerminate(_ notification: Notification) {
@@ -139,7 +210,7 @@ class MacAppDelegate: NSObject, NSApplicationDelegate {
 }
 #endif
 
-class NotificationDelegate: NSObject, UNUserNotificationCenterDelegate {
+final class NotificationDelegate: NSObject, UNUserNotificationCenterDelegate {
     static let shared = NotificationDelegate()
     weak var chatViewModel: ChatViewModel?
     
@@ -152,10 +223,18 @@ class NotificationDelegate: NSObject, UNUserNotificationCenterDelegate {
             // Get peer ID from userInfo
             if let peerID = userInfo["peerID"] as? String {
                 DispatchQueue.main.async {
-                    self.chatViewModel?.startPrivateChat(with: peerID)
+                    self.chatViewModel?.startPrivateChat(with: PeerID(str: peerID))
                 }
             }
         }
+        // Handle deeplink (e.g., geohash activity)
+        if let deep = userInfo["deeplink"] as? String, let url = URL(string: deep) {
+            #if os(iOS)
+            DispatchQueue.main.async { UIApplication.shared.open(url) }
+            #else
+            DispatchQueue.main.async { NSWorkspace.shared.open(url) }
+            #endif
+        }
         
         completionHandler()
     }
@@ -169,12 +248,21 @@ class NotificationDelegate: NSObject, UNUserNotificationCenterDelegate {
             // Get peer ID from userInfo
             if let peerID = userInfo["peerID"] as? String {
                 // Don't show notification if the private chat is already open
-                if chatViewModel?.selectedPrivateChatPeer == peerID {
+                if chatViewModel?.selectedPrivateChatPeer == PeerID(str: peerID) {
                     completionHandler([])
                     return
                 }
             }
         }
+        // Suppress geohash activity notification if we're already in that geohash channel
+        if identifier.hasPrefix("geo-activity-"),
+           let deep = userInfo["deeplink"] as? String,
+           let gh = deep.components(separatedBy: "/").last {
+            if case .location(let ch) = LocationChannelManager.shared.selectedChannel, ch.geohash == gh {
+                completionHandler([])
+                return
+            }
+        }
         
         // Show notification in all other cases
         completionHandler([.banner, .sound])
@@ -185,4 +273,4 @@ extension String {
     var nilIfEmpty: String? {
         self.isEmpty ? nil : self
     }
-}
+}

bitchat/Features/media/ImageUtils.swift

@@ -0,0 +1,203 @@
+import Foundation
+import ImageIO
+import UniformTypeIdentifiers
+#if os(iOS)
+import UIKit
+#else
+import AppKit
+#endif
+
+enum ImageUtilsError: Error {
+    case invalidImage
+    case encodingFailed
+}
+
+enum ImageUtils {
+    private static let compressionQuality: CGFloat = 0.82
+    private static let targetImageBytes: Int = 45_000
+
+    static func processImage(at url: URL, maxDimension: CGFloat = 448) throws -> URL {
+        // Security H1: Check file size BEFORE reading into memory
+        let attrs = try FileManager.default.attributesOfItem(atPath: url.path)
+        guard let fileSize = attrs[.size] as? Int else {
+            throw ImageUtilsError.invalidImage
+        }
+        // Allow up to 10MB source images (will be scaled down)
+        guard fileSize <= 10 * 1024 * 1024 else {
+            throw ImageUtilsError.invalidImage
+        }
+
+        let data = try Data(contentsOf: url)
+        #if os(iOS)
+        guard let image = UIImage(data: data) else { throw ImageUtilsError.invalidImage }
+        return try processImage(image, maxDimension: maxDimension)
+        #else
+        guard let image = NSImage(data: data) else { throw ImageUtilsError.invalidImage }
+        return try processImage(image, maxDimension: maxDimension)
+        #endif
+    }
+
+    #if os(iOS)
+    static func processImage(_ image: UIImage, maxDimension: CGFloat = 448) throws -> URL {
+        return try autoreleasepool {
+            // Scale the image first
+            let scaled = scaledImage(image, maxDimension: maxDimension)
+
+            // Get CGImage from UIImage - this is the key to stripping metadata
+            guard let cgImage = scaled.cgImage else {
+                throw ImageUtilsError.encodingFailed
+            }
+
+            // Use CGImageDestination to encode without metadata (same as macOS)
+            var quality = compressionQuality
+            guard var jpegData = encodeJPEG(from: cgImage, quality: quality) else {
+                throw ImageUtilsError.encodingFailed
+            }
+
+            // Compress to target size
+            while jpegData.count > targetImageBytes && quality > 0.3 {
+                quality -= 0.1
+                autoreleasepool {
+                    if let next = encodeJPEG(from: cgImage, quality: quality) {
+                        jpegData = next
+                    }
+                }
+            }
+
+            let outputURL = try makeOutputURL()
+            try jpegData.write(to: outputURL, options: .atomic)
+            return outputURL
+        }
+    }
+
+    private static func scaledImage(_ image: UIImage, maxDimension: CGFloat) -> UIImage {
+        let size = image.size
+        let maxSide = max(size.width, size.height)
+        guard maxSide > maxDimension else { return image }
+        let scale = maxDimension / maxSide
+        let newSize = CGSize(width: size.width * scale, height: size.height * scale)
+
+        // Draw into a new context to get a clean CGImage without metadata
+        UIGraphicsBeginImageContextWithOptions(newSize, true, 1.0)
+        image.draw(in: CGRect(origin: .zero, size: newSize))
+        let rendered = UIGraphicsGetImageFromCurrentImageContext()
+        UIGraphicsEndImageContext()
+        return rendered ?? image
+    }
+
+    // Shared EXIF-stripping JPEG encoder for both iOS and macOS
+    private static func encodeJPEG(from cgImage: CGImage, quality: CGFloat) -> Data? {
+        guard let data = CFDataCreateMutable(nil, 0) else {
+            return nil
+        }
+        guard let destination = CGImageDestinationCreateWithData(data, UTType.jpeg.identifier as CFString, 1, nil) else {
+            return nil
+        }
+        // Security: Strip ALL metadata (EXIF, GPS, TIFF, IPTC, XMP)
+        // By only specifying compression quality and no metadata keys,
+        // we ensure a clean JPEG with no privacy-leaking information
+        let options: [CFString: Any] = [
+            kCGImageDestinationLossyCompressionQuality: quality
+        ]
+        CGImageDestinationAddImage(destination, cgImage, options as CFDictionary)
+        guard CGImageDestinationFinalize(destination) else {
+            return nil
+        }
+        return data as Data
+    }
+    #else
+    static func processImage(_ image: NSImage, maxDimension: CGFloat = 448) throws -> URL {
+        return try autoreleasepool {
+            let scaled = scaledImage(image, maxDimension: maxDimension)
+            guard let inputCG = scaled.cgImage(forProposedRect: nil, context: nil, hints: nil) else {
+                throw ImageUtilsError.encodingFailed
+            }
+            let width = inputCG.width
+            let height = inputCG.height
+            let colorSpace = CGColorSpace(name: CGColorSpace.sRGB) ?? CGColorSpaceCreateDeviceRGB()
+            guard let context = CGContext(
+                data: nil,
+                width: width,
+                height: height,
+                bitsPerComponent: 8,
+                bytesPerRow: 0,
+                space: colorSpace,
+                bitmapInfo: CGImageAlphaInfo.premultipliedLast.rawValue
+            ) else {
+                throw ImageUtilsError.encodingFailed
+            }
+            context.draw(inputCG, in: CGRect(x: 0, y: 0, width: width, height: height))
+            guard let cgImage = context.makeImage() else {
+                throw ImageUtilsError.encodingFailed
+            }
+            var quality = compressionQuality
+            guard var jpegData = encodeJPEG(from: cgImage, quality: quality) else {
+                throw ImageUtilsError.encodingFailed
+            }
+            while jpegData.count > targetImageBytes && quality > 0.3 {
+                quality -= 0.1
+                autoreleasepool {
+                    if let next = encodeJPEG(from: cgImage, quality: quality) {
+                        jpegData = next
+                    }
+                }
+            }
+            let outputURL = try makeOutputURL()
+            try jpegData.write(to: outputURL, options: .atomic)
+            return outputURL
+        }
+    }
+
+    private static func scaledImage(_ image: NSImage, maxDimension: CGFloat) -> NSImage {
+        let size = image.size
+        let maxSide = max(size.width, size.height)
+        guard maxSide > maxDimension else { return image }
+        let scale = maxDimension / maxSide
+        let newSize = NSSize(width: size.width * scale, height: size.height * scale)
+        let scaledImage = NSImage(size: newSize)
+        scaledImage.lockFocus()
+        image.draw(in: NSRect(origin: .zero, size: newSize),
+                   from: NSRect(origin: .zero, size: size),
+                   operation: .copy,
+                   fraction: 1.0)
+        scaledImage.unlockFocus()
+        return scaledImage
+    }
+
+    // Shared EXIF-stripping JPEG encoder for both iOS and macOS
+    private static func encodeJPEG(from cgImage: CGImage, quality: CGFloat) -> Data? {
+        guard let data = CFDataCreateMutable(nil, 0) else {
+            return nil
+        }
+        guard let destination = CGImageDestinationCreateWithData(data, UTType.jpeg.identifier as CFString, 1, nil) else {
+            return nil
+        }
+        // Security: Strip ALL metadata (EXIF, GPS, TIFF, IPTC, XMP)
+        // By only specifying compression quality and no metadata keys,
+        // we ensure a clean JPEG with no privacy-leaking information
+        let options: [CFString: Any] = [
+            kCGImageDestinationLossyCompressionQuality: quality
+        ]
+        CGImageDestinationAddImage(destination, cgImage, options as CFDictionary)
+        guard CGImageDestinationFinalize(destination) else {
+            return nil
+        }
+        return data as Data
+    }
+    #endif
+
+    private static func makeOutputURL() throws -> URL {
+        let formatter = DateFormatter()
+        formatter.dateFormat = "yyyyMMdd_HHmmss"
+        let fileName = "img_\(formatter.string(from: Date())).jpg"
+
+        let directory = try applicationFilesDirectory().appendingPathComponent("images/outgoing", isDirectory: true)
+        try FileManager.default.createDirectory(at: directory, withIntermediateDirectories: true, attributes: nil)
+        return directory.appendingPathComponent(fileName)
+    }
+
+    private static func applicationFilesDirectory() throws -> URL {
+        let base = try FileManager.default.url(for: .applicationSupportDirectory, in: .userDomainMask, appropriateFor: nil, create: true)
+        return base.appendingPathComponent("files", isDirectory: true)
+    }
+}

bitchat/Features/voice/VoiceNotePlaybackController.swift

@@ -0,0 +1,193 @@
+import Foundation
+import AVFoundation
+import BitLogger
+
+/// Controls playback for a single voice note and coordinates exclusive playback across the app.
+final class VoiceNotePlaybackController: NSObject, ObservableObject, AVAudioPlayerDelegate {
+    @Published private(set) var isPlaying: Bool = false
+    @Published private(set) var currentTime: TimeInterval = 0
+    @Published private(set) var duration: TimeInterval = 0
+    @Published private(set) var progress: Double = 0
+
+    private var player: AVAudioPlayer?
+    private var timer: Timer?
+    private var url: URL
+
+    init(url: URL) {
+        self.url = url
+        super.init()
+        // Don't load anything eagerly - wait until user interaction or view is fully displayed
+    }
+
+    func loadDuration() {
+        guard duration == 0 else { return }
+
+        DispatchQueue.global(qos: .utility).async { [weak self] in
+            guard let self = self else { return }
+            do {
+                let player = try AVAudioPlayer(contentsOf: self.url)
+                let loadedDuration = player.duration
+                DispatchQueue.main.async { [weak self] in
+                    guard let self = self, self.duration == 0 else { return }
+                    self.duration = loadedDuration
+                }
+            } catch {
+                SecureLogger.error("Failed to load audio duration: \(error)", category: .session)
+            }
+        }
+    }
+
+    deinit {
+        timer?.invalidate()
+    }
+
+    func replaceURL(_ url: URL) {
+        guard url != self.url else { return }
+        stop()
+        self.url = url
+        player = nil
+        duration = 0
+        // Duration will be loaded on demand when needed
+    }
+
+    func togglePlayback() {
+        isPlaying ? pause() : play()
+    }
+
+    func play() {
+        guard ensurePlayerReady() else { return }
+        VoiceNotePlaybackCoordinator.shared.activate(self)
+        player?.play()
+        startTimer()
+        updateProgress()
+        isPlaying = true
+    }
+
+    func pause() {
+        player?.pause()
+        stopTimer()
+        updateProgress()
+        isPlaying = false
+    }
+
+    func stop() {
+        player?.stop()
+        player?.currentTime = 0
+        stopTimer()
+        updateProgress()
+        isPlaying = false
+        VoiceNotePlaybackCoordinator.shared.deactivate(self)
+    }
+
+    func seek(to fraction: Double) {
+        guard ensurePlayerReady() else { return }
+        let clamped = max(0, min(1, fraction))
+        if let player = player {
+            player.currentTime = clamped * player.duration
+            if isPlaying {
+                player.play()
+            }
+            updateProgress()
+        }
+    }
+
+    // MARK: - AVAudioPlayerDelegate
+
+    func audioPlayerDidFinishPlaying(_ player: AVAudioPlayer, successfully flag: Bool) {
+        // Delegate callback may be on background thread - ensure main thread for UI updates
+        DispatchQueue.main.async { [weak self] in
+            guard let self = self else { return }
+            self.stopTimer()
+            self.updateProgress()
+            self.isPlaying = false
+            VoiceNotePlaybackCoordinator.shared.deactivate(self)
+        }
+    }
+
+    // MARK: - Private Helpers
+
+    private func preparePlayer(for url: URL) {
+        // Prepare player synchronously (only called when playback is requested)
+        do {
+            let player = try AVAudioPlayer(contentsOf: url)
+            player.delegate = self
+            player.prepareToPlay()
+            self.player = player
+            duration = player.duration
+            currentTime = player.currentTime
+            progress = duration > 0 ? currentTime / duration : 0
+        } catch {
+            SecureLogger.error("Voice note playback failed for \(url.lastPathComponent): \(error)", category: .session)
+            player = nil
+            duration = 0
+            currentTime = 0
+            progress = 0
+        }
+    }
+
+    private func ensurePlayerReady() -> Bool {
+        if player == nil {
+            preparePlayer(for: url)
+        }
+        #if os(iOS)
+        let session = AVAudioSession.sharedInstance()
+        do {
+            try session.setCategory(.playback, mode: .spokenAudio, options: [.mixWithOthers])
+            try session.setActive(true, options: [])
+        } catch {
+            SecureLogger.error("Failed to activate audio session: \(error)", category: .session)
+        }
+        #endif
+        return player != nil
+    }
+
+    private func startTimer() {
+        if timer != nil { return }
+        timer = Timer.scheduledTimer(withTimeInterval: 0.05, repeats: true) { [weak self] _ in
+            self?.updateProgress()
+        }
+        if let timer = timer {
+            RunLoop.main.add(timer, forMode: .common)
+        }
+    }
+
+    private func stopTimer() {
+        timer?.invalidate()
+        timer = nil
+    }
+
+    private func updateProgress() {
+        guard let player = player else {
+            currentTime = 0
+            duration = 0
+            progress = 0
+            return
+        }
+        currentTime = player.currentTime
+        duration = player.duration
+        progress = duration > 0 ? currentTime / duration : 0
+    }
+}
+
+/// Ensures only one voice note plays at a time.
+final class VoiceNotePlaybackCoordinator {
+    static let shared = VoiceNotePlaybackCoordinator()
+
+    private weak var activeController: VoiceNotePlaybackController?
+
+    private init() {}
+
+    func activate(_ controller: VoiceNotePlaybackController) {
+        if activeController === controller {
+            return
+        }
+        activeController?.pause()
+        activeController = controller
+    }
+
+    func deactivate(_ controller: VoiceNotePlaybackController) {
+        if activeController === controller {
+            activeController = nil
+        }
+    }
+}

bitchat/Features/voice/VoiceRecorder.swift

@@ -0,0 +1,170 @@
+import Foundation
+import AVFoundation
+
+/// Manages audio capture for mesh voice notes with predictable encoding settings.
+/// Recording runs on an internal serial queue to avoid AVAudioSession contention.
+final class VoiceRecorder: NSObject, AVAudioRecorderDelegate {
+    enum RecorderError: Error {
+        case microphoneAccessDenied
+        case recorderInitializationFailed
+        case recordingInProgress
+    }
+
+    static let shared = VoiceRecorder()
+
+    private let queue = DispatchQueue(label: "com.bitchat.voice-recorder")
+    private let paddingInterval: TimeInterval = 0.5
+    private let maxRecordingDuration: TimeInterval = 120
+
+    private var recorder: AVAudioRecorder?
+    private var currentURL: URL?
+    private var stopWorkItem: DispatchWorkItem?
+
+    private override init() {
+        super.init()
+    }
+
+    // MARK: - Permissions
+
+    @discardableResult
+    func requestPermission() async -> Bool {
+        #if os(iOS)
+        return await withCheckedContinuation { continuation in
+            AVAudioSession.sharedInstance().requestRecordPermission { granted in
+                continuation.resume(returning: granted)
+            }
+        }
+        #elseif os(macOS)
+        return await withCheckedContinuation { continuation in
+            AVCaptureDevice.requestAccess(for: .audio) { granted in
+                continuation.resume(returning: granted)
+            }
+        }
+        #else
+        return true
+        #endif
+    }
+
+    // MARK: - Recording Lifecycle
+
+    func startRecording() throws -> URL {
+        try queue.sync {
+            if recorder?.isRecording == true {
+                throw RecorderError.recordingInProgress
+            }
+
+            #if os(iOS)
+            let session = AVAudioSession.sharedInstance()
+            guard session.recordPermission == .granted else {
+                throw RecorderError.microphoneAccessDenied
+            }
+            try session.setCategory(
+                .playAndRecord,
+                mode: .default,
+                options: [.defaultToSpeaker, .allowBluetoothA2DP, .allowBluetoothHFP]
+            )
+            try session.setActive(true, options: .notifyOthersOnDeactivation)
+            #endif
+            #if os(macOS)
+            guard AVCaptureDevice.authorizationStatus(for: .audio) == .authorized else {
+                throw RecorderError.microphoneAccessDenied
+            }
+            #endif
+
+            let outputURL = try makeOutputURL()
+            let settings: [String: Any] = [
+                AVFormatIDKey: kAudioFormatMPEG4AAC,
+                AVSampleRateKey: 16_000,
+                AVNumberOfChannelsKey: 1,
+                AVEncoderBitRateKey: 16_000
+            ]
+
+            let audioRecorder = try AVAudioRecorder(url: outputURL, settings: settings)
+            audioRecorder.delegate = self
+            audioRecorder.isMeteringEnabled = true
+            audioRecorder.prepareToRecord()
+            audioRecorder.record(forDuration: maxRecordingDuration)
+
+            recorder = audioRecorder
+            currentURL = outputURL
+            stopWorkItem?.cancel()
+            stopWorkItem = nil
+            return outputURL
+        }
+    }
+
+    func stopRecording(completion: @escaping (URL?) -> Void) {
+        queue.async { [weak self] in
+            guard let self = self, let recorder = self.recorder, recorder.isRecording else {
+                completion(self?.currentURL)
+                return
+            }
+
+            let item = DispatchWorkItem { [weak self] in
+                guard let self = self else { return }
+                recorder.stop()
+                self.cleanupSession()
+                let url = self.currentURL
+                self.recorder = nil
+                self.currentURL = url
+                completion(url)
+            }
+            self.stopWorkItem = item
+            self.queue.asyncAfter(deadline: .now() + self.paddingInterval, execute: item)
+        }
+    }
+
+    func cancelRecording() {
+        queue.async { [weak self] in
+            guard let self = self else { return }
+            self.stopWorkItem?.cancel()
+            self.stopWorkItem = nil
+            if let recorder = self.recorder, recorder.isRecording {
+                recorder.stop()
+            }
+            self.cleanupSession()
+            if let url = self.currentURL {
+                try? FileManager.default.removeItem(at: url)
+            }
+            self.recorder = nil
+            self.currentURL = nil
+        }
+    }
+
+    // MARK: - Metering
+
+    func currentAveragePower() -> Float {
+        queue.sync {
+            recorder?.updateMeters()
+            return recorder?.averagePower(forChannel: 0) ?? -160
+        }
+    }
+
+    // MARK: - Helpers
+
+    private func makeOutputURL() throws -> URL {
+        let formatter = DateFormatter()
+        formatter.dateFormat = "yyyyMMdd_HHmmss"
+        let fileName = "voice_\(formatter.string(from: Date())).m4a"
+
+        let baseDirectory = try applicationFilesDirectory().appendingPathComponent("voicenotes/outgoing", isDirectory: true)
+        try FileManager.default.createDirectory(at: baseDirectory, withIntermediateDirectories: true, attributes: nil)
+        return baseDirectory.appendingPathComponent(fileName)
+    }
+
+    private func applicationFilesDirectory() throws -> URL {
+        #if os(iOS)
+        return try FileManager.default.url(for: .applicationSupportDirectory, in: .userDomainMask, appropriateFor: nil, create: true)
+            .appendingPathComponent("files", isDirectory: true)
+        #else
+        let base = try FileManager.default.url(for: .applicationSupportDirectory, in: .userDomainMask, appropriateFor: nil, create: true)
+        return base.appendingPathComponent("files", isDirectory: true)
+        #endif
+    }
+
+    private func cleanupSession() {
+        #if os(iOS)
+        try? AVAudioSession.sharedInstance().setActive(false, options: .notifyOthersOnDeactivation)
+        #endif
+    }
+}

bitchat/Features/voice/Waveform.swift

@@ -0,0 +1,113 @@
+import AVFoundation
+import Foundation
+import BitLogger
+
+/// Generates and caches downsampled waveforms for audio files so UI rendering is cheap.
+final class WaveformCache {
+    static let shared = WaveformCache()
+
+    private let queue = DispatchQueue(label: "com.bitchat.waveform-cache", attributes: .concurrent)
+    private var cache: [URL: (waveform: [Float], lastAccess: Date)] = [:]
+    private let maxCacheSize = 20  // Limit cache to prevent unbounded memory growth
+
+    private init() {}
+
+    func cachedWaveform(for url: URL) -> [Float]? {
+        queue.sync {
+            guard let entry = cache[url] else { return nil }
+            return entry.waveform
+        }
+    }
+
+    func waveform(for url: URL, bins: Int = 120, completion: @escaping ([Float]) -> Void) {
+        queue.async { [weak self] in
+            guard let self = self else { return }
+
+            // Check cache (read-only, no update needed on cache hit for performance)
+            if let entry = self.cache[url] {
+                DispatchQueue.main.async { completion(entry.waveform) }
+                return
+            }
+
+            guard let computed = self.computeWaveform(url: url, bins: bins) else {
+                DispatchQueue.main.async { completion([]) }
+                return
+            }
+
+            self.queue.async(flags: .barrier) { [weak self] in
+                guard let self = self else { return }
+
+                // Evict oldest entry if cache is full
+                if self.cache.count >= self.maxCacheSize {
+                    if let oldest = self.cache.min(by: { $0.value.lastAccess < $1.value.lastAccess }) {
+                        self.cache.removeValue(forKey: oldest.key)
+                    }
+                }
+
+                self.cache[url] = (computed, Date())
+            }
+            DispatchQueue.main.async { completion(computed) }
+        }
+    }
+
+    func purge(url: URL) {
+        queue.async(flags: .barrier) { [weak self] in
+            self?.cache.removeValue(forKey: url)
+        }
+    }
+
+    func purgeAll() {
+        queue.async(flags: .barrier) { [weak self] in
+            self?.cache.removeAll()
+        }
+    }
+
+    private func computeWaveform(url: URL, bins: Int) -> [Float]? {
+        guard bins > 0 else { return nil }
+        // Use autoreleasepool to manage memory from audio buffer allocations
+        return autoreleasepool {
+            do {
+                let audioFile = try AVAudioFile(forReading: url)
+                let length = Int(audioFile.length)
+                guard length > 0 else { return nil }
+
+                guard let buffer = AVAudioPCMBuffer(pcmFormat: audioFile.processingFormat, frameCapacity: AVAudioFrameCount(length)) else {
+                    return nil
+                }
+                try audioFile.read(into: buffer, frameCount: AVAudioFrameCount(length))
+                guard let channelData = buffer.floatChannelData else { return nil }
+
+                let channelCount = Int(audioFile.processingFormat.channelCount)
+                let frameLength = Int(buffer.frameLength)
+                let samplesPerBin = max(1, frameLength / bins)
+
+                var magnitudes: [Float] = Array(repeating: 0, count: bins)
+                for bin in 0..<bins {
+                    let start = bin * samplesPerBin
+                    let end = min(frameLength, start + samplesPerBin)
+                    if start >= end { break }
+
+                    var sum: Float = 0
+                    var sampleCount = 0
+                    for frame in start..<end {
+                        var sampleValue: Float = 0
+                        for channel in 0..<channelCount {
+                            sampleValue += fabsf(channelData[channel][frame])
+                        }
+                        sum += sampleValue / Float(channelCount)
+                        sampleCount += 1
+                    }
+                    magnitudes[bin] = sampleCount > 0 ? sum / Float(sampleCount) : 0
+                }
+
+                if let maxMagnitude = magnitudes.max(), maxMagnitude > 0 {
+                    magnitudes = magnitudes.map { min($0 / maxMagnitude, 1.0) }
+                }
+                return magnitudes
+            } catch {
+                SecureLogger.error("Waveform extraction failed for \(url.lastPathComponent): \(error)", category: .session)
+                return nil
+            }
+        }
+    }
+}

bitchat/Identity/IdentityModels.swift

@@ -6,13 +6,88 @@
 // For more information, see <https://unlicense.org>
 //
 
+///
+/// # IdentityModels
+///
+/// Defines BitChat's innovative three-layer identity model that balances
+/// privacy, security, and usability in a decentralized mesh network.
+///
+/// ## Overview
+/// BitChat's identity system separates concerns across three distinct layers:
+/// 1. **Ephemeral Identity**: Short-lived, rotatable peer IDs for privacy
+/// 2. **Cryptographic Identity**: Long-term Noise static keys for security
+/// 3. **Social Identity**: User-assigned names and trust relationships
+///
+/// This separation allows users to maintain stable cryptographic identities
+/// while frequently rotating their network identifiers for privacy.
+///
+/// ## Three-Layer Architecture
+///
+/// ### Layer 1: Ephemeral Identity
+/// - Random 8-byte peer IDs that rotate periodically
+/// - Provides network-level privacy and prevents tracking
+/// - Changes don't affect cryptographic relationships
+/// - Includes handshake state tracking
+///
+/// ### Layer 2: Cryptographic Identity
+/// - Based on Noise Protocol static key pairs
+/// - Fingerprint derived from SHA256 of public key
+/// - Enables end-to-end encryption and authentication
+/// - Persists across peer ID rotations
+///
+/// ### Layer 3: Social Identity
+/// - User-assigned names (petnames) for contacts
+/// - Trust levels from unknown to verified
+/// - Favorite/blocked status
+/// - Personal notes and metadata
+///
+/// ## Privacy Design
+/// The model is designed with privacy-first principles:
+/// - No mandatory persistent storage
+/// - Optional identity caching with user consent
+/// - Ephemeral IDs prevent long-term tracking
+/// - Social mappings stored locally only
+///
+/// ## Trust Model
+/// Four levels of trust:
+/// 1. **Unknown**: New or unverified peers
+/// 2. **Casual**: Basic interaction history
+/// 3. **Trusted**: User has explicitly trusted
+/// 4. **Verified**: Cryptographic verification completed
+///
+/// ## Identity Resolution
+/// When a peer rotates their ephemeral ID:
+/// 1. Cryptographic handshake reveals their fingerprint
+/// 2. System looks up social identity by fingerprint
+/// 3. UI seamlessly maintains user relationships
+/// 4. Historical messages remain properly attributed
+///
+/// ## Conflict Resolution
+/// Handles edge cases like:
+/// - Multiple peers claiming same nickname
+/// - Nickname changes and conflicts
+/// - Identity rotation during active chats
+/// - Network partitions and rejoins
+///
+/// ## Usage Example
+/// ```swift
+/// // When peer connects with new ID
+/// let ephemeral = EphemeralIdentity(peerID: "abc123", ...)
+/// // After handshake
+/// let crypto = CryptographicIdentity(fingerprint: "sha256...", ...)
+/// // User assigns name
+/// let social = SocialIdentity(localPetname: "Alice", ...)
+/// ```
+///
+
 import Foundation
 
 // MARK: - Three-Layer Identity Model
 
-// Layer 1: Ephemeral (per-session)
+/// Represents the ephemeral layer of identity - short-lived peer IDs that provide network privacy.
+/// These IDs rotate periodically to prevent tracking while maintaining cryptographic relationships.
 struct EphemeralIdentity {
-    let peerID: String          // 8 random bytes
+    let peerID: PeerID          // 8 random bytes
     let sessionStart: Date
     var handshakeState: HandshakeState
 }
@@ -25,15 +100,21 @@ enum HandshakeState {
     case failed(reason: String)
 }
 
-// Layer 2: Cryptographic (persistent)
+/// Represents the cryptographic layer of identity - the stable Noise Protocol static key pair.
+/// This identity persists across ephemeral ID rotations and enables secure communication.
+/// The fingerprint serves as the permanent identifier for a peer's cryptographic identity.
 struct CryptographicIdentity: Codable {
     let fingerprint: String     // SHA256 of public key
     let publicKey: Data         // Noise static public key
+    // Optional Ed25519 signing public key (used to authenticate public messages)
+    var signingPublicKey: Data? = nil
     let firstSeen: Date
     let lastHandshake: Date?
 }
 
-// Layer 3: Social (user-assigned)
+/// Represents the social layer of identity - user-assigned names and trust relationships.
+/// This layer provides human-friendly identification and relationship management.
+/// All data in this layer is local-only and never transmitted over the network.
 struct SocialIdentity: Codable {
     let fingerprint: String
     var localPetname: String?   // User's name for this peer
@@ -53,6 +134,9 @@ enum TrustLevel: String, Codable {
 
 // MARK: - Identity Cache
 
+/// Persistent storage for identity mappings and relationships.
+/// Provides efficient lookup between fingerprints, nicknames, and social identities.
+/// Storage is optional and controlled by user privacy settings.
 struct IdentityCache: Codable {
     // Fingerprint -> Social mapping
     var socialIdentities: [String: SocialIdentity] = [:]
@@ -67,74 +151,14 @@ struct IdentityCache: Codable {
     // Last interaction timestamps (privacy: optional)
     var lastInteractions: [String: Date] = [:] 
     
+    // Blocked Nostr pubkeys (lowercased hex) for geohash chats
+    var blockedNostrPubkeys: Set<String> = []
+    
     // Schema version for future migrations
     var version: Int = 1
 }
 
-// MARK: - Identity Resolution
-
-enum IdentityHint {
-    case unknown
-    case likelyKnown(fingerprint: String)
-    case ambiguous(candidates: Set<String>)
-    case verified(fingerprint: String)
-}
-
-// MARK: - Pending Actions
-
-struct PendingActions {
-    var toggleFavorite: Bool?
-    var setTrustLevel: TrustLevel?
-    var setPetname: String?
-}
-
-// MARK: - Privacy Settings
-
-struct PrivacySettings: Codable {
-    // Level 1: Maximum privacy (default)
-    var persistIdentityCache = false
-    var showLastSeen = false
-    
-    // Level 2: Convenience
-    var autoAcceptKnownFingerprints = false
-    var rememberNicknameHistory = false
-    
-    // Level 3: Social
-    var shareTrustNetworkHints = false  // "3 mutual contacts trust this person"
-}
-
-// MARK: - Conflict Resolution
-
-enum ConflictResolution {
-    case acceptNew(petname: String)      // "John (2)"
-    case rejectNew
-    case blockFingerprint(String)
-    case alertUser(message: String)
-}
-
-// MARK: - UI State
-
-struct PeerUIState {
-    let peerID: String
-    let nickname: String
-    var identityState: IdentityState
-    var connectionQuality: ConnectionQuality
-    
-    enum IdentityState {
-        case unknown                    // Gray - No identity info
-        case unverifiedKnown(String)   // Blue - Handshake done, matches cache
-        case verified(String)          // Green - Cryptographically verified
-        case conflict(String, String)  // Red - Nickname doesn't match fingerprint
-        case pending                   // Yellow - Handshake in progress
-    }
-}
-
-enum ConnectionQuality {
-    case excellent
-    case good
-    case poor
-    case disconnected
-}
+//
 
 // MARK: - Migration Support
-// Removed LegacyFavorite - no longer needed
+//

bitchat/Identity/SecureIdentityStateManager.swift

@@ -6,24 +6,147 @@
 // For more information, see <https://unlicense.org>
 //
 
+///
+/// # SecureIdentityStateManager
+///
+/// Manages the persistent storage and retrieval of identity mappings with
+/// encryption at rest. This singleton service maintains the relationship between
+/// ephemeral peer IDs, cryptographic fingerprints, and social identities.
+///
+/// ## Overview
+/// The SecureIdentityStateManager provides a secure, privacy-preserving way to
+/// maintain identity relationships across app launches. It implements:
+/// - Encrypted storage of identity mappings
+/// - In-memory caching for performance
+/// - Thread-safe access patterns
+/// - Automatic debounced persistence
+///
+/// ## Architecture
+/// The manager operates at three levels:
+/// 1. **In-Memory State**: Fast access to active identities
+/// 2. **Encrypted Cache**: Persistent storage in Keychain
+/// 3. **Privacy Controls**: User-configurable persistence settings
+///
+/// ## Security Features
+///
+/// ### Encryption at Rest
+/// - Identity cache encrypted with AES-GCM
+/// - Unique 256-bit encryption key per device
+/// - Key stored separately in Keychain
+/// - No plaintext identity data on disk
+///
+/// ### Privacy by Design
+/// - Persistence is optional (user-controlled)
+/// - Minimal data retention
+/// - No cloud sync or backup
+/// - Automatic cleanup of stale entries
+///
+/// ### Thread Safety
+/// - Concurrent read access via GCD barriers
+/// - Write operations serialized
+/// - Atomic state updates
+/// - No data races or corruption
+///
+/// ## Data Model
+/// Manages three types of identity data:
+/// 1. **Ephemeral Sessions**: Current peer connections
+/// 2. **Cryptographic Identities**: Public keys and fingerprints
+/// 3. **Social Identities**: User-assigned names and trust
+///
+/// ## Persistence Strategy
+/// - Changes batched and debounced (2-second window)
+/// - Automatic save on app termination
+/// - Crash-resistant with atomic writes
+/// - Migration support for schema changes
+///
+/// ## Usage Patterns
+/// ```swift
+/// // Register a new peer identity
+/// manager.registerPeerIdentity(peerID, publicKey, fingerprint)
+/// 
+/// // Update social identity
+/// manager.updateSocialIdentity(fingerprint, nickname, trustLevel)
+/// 
+/// // Query identity
+/// let identity = manager.resolvePeerIdentity(peerID)
+/// ```
+///
+/// ## Performance Optimizations
+/// - In-memory cache eliminates Keychain roundtrips
+/// - Debounced saves reduce I/O operations
+/// - Efficient data structures for lookups
+/// - Background queue for expensive operations
+///
+/// ## Privacy Considerations
+/// - Users can disable all persistence
+/// - Identity cache can be wiped instantly
+/// - No analytics or telemetry
+/// - Ephemeral mode for high-risk users
+///
+/// ## Future Enhancements
+/// - Selective identity export
+/// - Cross-device identity sync (optional)
+/// - Identity attestation support
+/// - Advanced conflict resolution
+///
+
+import BitLogger
 import Foundation
 import CryptoKit
 
-class SecureIdentityStateManager {
-    static let shared = SecureIdentityStateManager()
+protocol SecureIdentityStateManagerProtocol {
+    // MARK: Secure Loading/Saving
+    func forceSave()
     
-    private let keychain = KeychainManager.shared
+    // MARK: Social Identity Management
+    func getSocialIdentity(for fingerprint: String) -> SocialIdentity?
+    
+    // MARK: Cryptographic Identities
+    func upsertCryptographicIdentity(fingerprint: String, noisePublicKey: Data, signingPublicKey: Data?, claimedNickname: String?)
+    func getCryptoIdentitiesByPeerIDPrefix(_ peerID: PeerID) -> [CryptographicIdentity]
+    func updateSocialIdentity(_ identity: SocialIdentity)
+    
+    // MARK: Favorites Management
+    func getFavorites() -> Set<String>
+    func setFavorite(_ fingerprint: String, isFavorite: Bool)
+    func isFavorite(fingerprint: String) -> Bool
+    
+    // MARK: Blocked Users Management
+    func isBlocked(fingerprint: String) -> Bool
+    func setBlocked(_ fingerprint: String, isBlocked: Bool)
+    
+    // MARK: Geohash (Nostr) Blocking
+    func isNostrBlocked(pubkeyHexLowercased: String) -> Bool
+    func setNostrBlocked(_ pubkeyHexLowercased: String, isBlocked: Bool)
+    func getBlockedNostrPubkeys() -> Set<String>
+    
+    // MARK: Ephemeral Session Management
+    func registerEphemeralSession(peerID: PeerID, handshakeState: HandshakeState)
+    func updateHandshakeState(peerID: PeerID, state: HandshakeState)
+    
+    // MARK: Cleanup
+    func clearAllIdentityData()
+    func removeEphemeralSession(peerID: PeerID)
+    
+    // MARK: Verification
+    func setVerified(fingerprint: String, verified: Bool)
+    func isVerified(fingerprint: String) -> Bool
+    func getVerifiedFingerprints() -> Set<String>
+}
+
+/// Singleton manager for secure identity state persistence and retrieval.
+/// Provides thread-safe access to identity mappings with encryption at rest.
+/// All identity data is stored encrypted in the device Keychain for security.
+final class SecureIdentityStateManager: SecureIdentityStateManagerProtocol {
+    private let keychain: KeychainManagerProtocol
     private let cacheKey = "bitchat.identityCache.v2"
     private let encryptionKeyName = "identityCacheEncryptionKey"
     
     // In-memory state
-    private var ephemeralSessions: [String: EphemeralIdentity] = [:]
+    private var ephemeralSessions: [PeerID: EphemeralIdentity] = [:]
     private var cryptographicIdentities: [String: CryptographicIdentity] = [:]
     private var cache: IdentityCache = IdentityCache()
     
-    // Pending actions before handshake
-    private var pendingActions: [String: PendingActions] = [:]
-    
     // Thread safety
     private let queue = DispatchQueue(label: "bitchat.identity.state", attributes: .concurrent)
     
@@ -35,14 +158,16 @@ class SecureIdentityStateManager {
     // Encryption key
     private let encryptionKey: SymmetricKey
     
-    private init() {
+    init(_ keychain: KeychainManagerProtocol) {
+        self.keychain = keychain
+        
         // Generate or retrieve encryption key from keychain
         let loadedKey: SymmetricKey
         
         // Try to load from keychain
         if let keyData = keychain.getIdentityKey(forKey: encryptionKeyName) {
             loadedKey = SymmetricKey(data: keyData)
-            SecureLogger.logKeyOperation("load", keyType: "identity cache encryption key", success: true)
+            SecureLogger.logKeyOperation(.load, keyType: "identity cache encryption key", success: true)
         }
         // Generate new key if needed
         else {
@@ -50,7 +175,7 @@ class SecureIdentityStateManager {
             let keyData = loadedKey.withUnsafeBytes { Data($0) }
             // Save to keychain
             let saved = keychain.saveIdentityKey(keyData, forKey: encryptionKeyName)
-            SecureLogger.logKeyOperation("generate", keyType: "identity cache encryption key", success: saved)
+            SecureLogger.logKeyOperation(.generate, keyType: "identity cache encryption key", success: saved)
         }
         
         self.encryptionKey = loadedKey
@@ -59,9 +184,13 @@ class SecureIdentityStateManager {
         loadIdentityCache()
     }
     
+    deinit {
+        forceSave()
+    }
+    
     // MARK: - Secure Loading/Saving
     
-    func loadIdentityCache() {
+    private func loadIdentityCache() {
         guard let encryptedData = keychain.getIdentityKey(forKey: cacheKey) else {
             // No existing cache, start fresh
             return
@@ -73,16 +202,11 @@ class SecureIdentityStateManager {
             cache = try JSONDecoder().decode(IdentityCache.self, from: decryptedData)
         } catch {
             // Log error but continue with empty cache
-            SecureLogger.logError(error, context: "Failed to load identity cache", category: SecureLogger.security)
+            SecureLogger.error(error, context: "Failed to load identity cache", category: .security)
         }
     }
     
-    deinit {
-        // Force save any pending changes
-        forceSave()
-    }
-    
-    func saveIdentityCache() {
+    private func saveIdentityCache() {
         // Mark that we need to save
         pendingSave = true
         
@@ -104,35 +228,17 @@ class SecureIdentityStateManager {
             let sealedBox = try AES.GCM.seal(data, using: encryptionKey)
             let saved = keychain.saveIdentityKey(sealedBox.combined!, forKey: cacheKey)
             if saved {
-                SecureLogger.log("Identity cache saved to keychain", category: SecureLogger.security, level: .debug)
+                SecureLogger.debug("Identity cache saved to keychain", category: .security)
             }
         } catch {
-            SecureLogger.logError(error, context: "Failed to save identity cache", category: SecureLogger.security)
+            SecureLogger.error(error, context: "Failed to save identity cache", category: .security)
         }
     }
     
     // Force immediate save (for app termination)
     func forceSave() {
         saveTimer?.invalidate()
-        if pendingSave {
-            performSave()
-        }
-    }
-    
-    // MARK: - Identity Resolution
-    
-    func resolveIdentity(peerID: String, claimedNickname: String) -> IdentityHint {
-        queue.sync {
-            // Check if we have candidates based on nickname
-            if let fingerprints = cache.nicknameIndex[claimedNickname] {
-                if fingerprints.count == 1 {
-                    return .likelyKnown(fingerprint: fingerprints.first!)
-                } else {
-                    return .ambiguous(candidates: fingerprints)
-                }
-            }
-            return .unknown
-        }
+        performSave()
     }
     
     // MARK: - Social Identity Management
@@ -142,10 +248,84 @@ class SecureIdentityStateManager {
             return cache.socialIdentities[fingerprint]
         }
     }
-    
-    func getAllSocialIdentities() -> [SocialIdentity] {
+
+    // MARK: - Cryptographic Identities
+
+    /// Insert or update a cryptographic identity and optionally persist its signing key and claimed nickname.
+    /// - Parameters:
+    ///   - fingerprint: SHA-256 hex of the Noise static public key
+    ///   - noisePublicKey: Noise static public key data
+    ///   - signingPublicKey: Optional Ed25519 signing public key for authenticating public messages
+    ///   - claimedNickname: Optional latest claimed nickname to persist into social identity
+    func upsertCryptographicIdentity(fingerprint: String, noisePublicKey: Data, signingPublicKey: Data?, claimedNickname: String? = nil) {
+        queue.async(flags: .barrier) {
+            let now = Date()
+            if var existing = self.cryptographicIdentities[fingerprint] {
+                // Update keys if changed
+                if existing.publicKey != noisePublicKey {
+                    existing = CryptographicIdentity(
+                        fingerprint: fingerprint,
+                        publicKey: noisePublicKey,
+                        signingPublicKey: signingPublicKey ?? existing.signingPublicKey,
+                        firstSeen: existing.firstSeen,
+                        lastHandshake: now
+                    )
+                    self.cryptographicIdentities[fingerprint] = existing
+                } else {
+                    // Update signing key and lastHandshake
+                    existing.signingPublicKey = signingPublicKey ?? existing.signingPublicKey
+                    let updated = CryptographicIdentity(
+                        fingerprint: existing.fingerprint,
+                        publicKey: existing.publicKey,
+                        signingPublicKey: existing.signingPublicKey,
+                        firstSeen: existing.firstSeen,
+                        lastHandshake: now
+                    )
+                    self.cryptographicIdentities[fingerprint] = updated
+                }
+                // Persist updated state (already assigned in branches above)
+            } else {
+                // New entry
+                let entry = CryptographicIdentity(
+                    fingerprint: fingerprint,
+                    publicKey: noisePublicKey,
+                    signingPublicKey: signingPublicKey,
+                    firstSeen: now,
+                    lastHandshake: now
+                )
+                self.cryptographicIdentities[fingerprint] = entry
+            }
+
+            // Optionally persist claimed nickname into social identity
+            if let claimed = claimedNickname {
+                var identity = self.cache.socialIdentities[fingerprint] ?? SocialIdentity(
+                    fingerprint: fingerprint,
+                    localPetname: nil,
+                    claimedNickname: claimed,
+                    trustLevel: .unknown,
+                    isFavorite: false,
+                    isBlocked: false,
+                    notes: nil
+                )
+                // Update claimed nickname if changed
+                if identity.claimedNickname != claimed {
+                    identity.claimedNickname = claimed
+                    self.cache.socialIdentities[fingerprint] = identity
+                } else if self.cache.socialIdentities[fingerprint] == nil {
+                    self.cache.socialIdentities[fingerprint] = identity
+                }
+            }
+
+            self.saveIdentityCache()
+        }
+    }
+
+    /// Find cryptographic identities whose fingerprint prefix matches a peerID (16-hex) short ID
+    func getCryptoIdentitiesByPeerIDPrefix(_ peerID: PeerID) -> [CryptographicIdentity] {
         queue.sync {
-            return Array(cache.socialIdentities.values)
+            // Defensive: ensure hex and correct length
+            guard peerID.isShort else { return [] }
+            return cryptographicIdentities.values.filter { $0.fingerprint.hasPrefix(peerID.id) }
         }
     }
     
@@ -223,7 +403,7 @@ class SecureIdentityStateManager {
     }
     
     func setBlocked(_ fingerprint: String, isBlocked: Bool) {
-        SecureLogger.log("User \(isBlocked ? "blocked" : "unblocked"): \(fingerprint)", category: SecureLogger.security, level: .info)
+        SecureLogger.info("User \(isBlocked ? "blocked" : "unblocked"): \(fingerprint)", category: .security)
         
         queue.async(flags: .barrier) {
             if var identity = self.cache.socialIdentities[fingerprint] {
@@ -248,10 +428,34 @@ class SecureIdentityStateManager {
             self.saveIdentityCache()
         }
     }
+
+    // MARK: - Geohash (Nostr) Blocking
+    
+    func isNostrBlocked(pubkeyHexLowercased: String) -> Bool {
+        queue.sync {
+            return cache.blockedNostrPubkeys.contains(pubkeyHexLowercased.lowercased())
+        }
+    }
+    
+    func setNostrBlocked(_ pubkeyHexLowercased: String, isBlocked: Bool) {
+        let key = pubkeyHexLowercased.lowercased()
+        queue.async(flags: .barrier) {
+            if isBlocked {
+                self.cache.blockedNostrPubkeys.insert(key)
+            } else {
+                self.cache.blockedNostrPubkeys.remove(key)
+            }
+            self.saveIdentityCache()
+        }
+    }
+    
+    func getBlockedNostrPubkeys() -> Set<String> {
+        queue.sync { cache.blockedNostrPubkeys }
+    }
     
     // MARK: - Ephemeral Session Management
     
-    func registerEphemeralSession(peerID: String, handshakeState: HandshakeState = .none) {
+    func registerEphemeralSession(peerID: PeerID, handshakeState: HandshakeState = .none) {
         queue.async(flags: .barrier) {
             self.ephemeralSessions[peerID] = EphemeralIdentity(
                 peerID: peerID,
@@ -261,7 +465,7 @@ class SecureIdentityStateManager {
         }
     }
     
-    func updateHandshakeState(peerID: String, state: HandshakeState) {
+    func updateHandshakeState(peerID: PeerID, state: HandshakeState) {
         queue.async(flags: .barrier) {
             self.ephemeralSessions[peerID]?.handshakeState = state
             
@@ -273,81 +477,32 @@ class SecureIdentityStateManager {
         }
     }
     
-    func getHandshakeState(peerID: String) -> HandshakeState? {
-        queue.sync {
-            return ephemeralSessions[peerID]?.handshakeState
-        }
-    }
-    
-    // MARK: - Pending Actions
-    
-    func setPendingAction(peerID: String, action: PendingActions) {
-        queue.async(flags: .barrier) {
-            self.pendingActions[peerID] = action
-        }
-    }
-    
-    func applyPendingActions(peerID: String, fingerprint: String) {
-        queue.async(flags: .barrier) {
-            guard let actions = self.pendingActions[peerID] else { return }
-            
-            // Get or create social identity
-            var identity = self.cache.socialIdentities[fingerprint] ?? SocialIdentity(
-                fingerprint: fingerprint,
-                localPetname: nil,
-                claimedNickname: "Unknown",
-                trustLevel: .unknown,
-                isFavorite: false,
-                isBlocked: false,
-                notes: nil
-            )
-            
-            // Apply pending actions
-            if let toggleFavorite = actions.toggleFavorite {
-                identity.isFavorite = toggleFavorite
-            }
-            if let trustLevel = actions.setTrustLevel {
-                identity.trustLevel = trustLevel
-            }
-            if let petname = actions.setPetname {
-                identity.localPetname = petname
-            }
-            
-            // Save updated identity
-            self.cache.socialIdentities[fingerprint] = identity
-            self.pendingActions.removeValue(forKey: peerID)
-            self.saveIdentityCache()
-        }
-    }
-    
     // MARK: - Cleanup
     
     func clearAllIdentityData() {
-        SecureLogger.log("Clearing all identity data", category: SecureLogger.security, level: .warning)
+        SecureLogger.warning("Clearing all identity data", category: .security)
         
         queue.async(flags: .barrier) {
             self.cache = IdentityCache()
             self.ephemeralSessions.removeAll()
             self.cryptographicIdentities.removeAll()
-            self.pendingActions.removeAll()
             
             // Delete from keychain
             let deleted = self.keychain.deleteIdentityKey(forKey: self.cacheKey)
-            SecureLogger.logKeyOperation("delete", keyType: "identity cache", success: deleted)
+            SecureLogger.logKeyOperation(.delete, keyType: "identity cache", success: deleted)
         }
     }
     
-    func removeEphemeralSession(peerID: String) {
+    func removeEphemeralSession(peerID: PeerID) {
         queue.async(flags: .barrier) {
             self.ephemeralSessions.removeValue(forKey: peerID)
-            self.pendingActions.removeValue(forKey: peerID)
         }
     }
     
     // MARK: - Verification
     
     func setVerified(fingerprint: String, verified: Bool) {
-        SecureLogger.log("Fingerprint \(verified ? "verified" : "unverified"): \(fingerprint)", category: SecureLogger.security, level: .info)
+        SecureLogger.info("Fingerprint \(verified ? "verified" : "unverified"): \(fingerprint)", category: .security)
         
         queue.async(flags: .barrier) {
             if verified {
@@ -377,4 +532,4 @@ class SecureIdentityStateManager {
             return cache.verifiedFingerprints
         }
     }
-}
+}

bitchat/Info.plist

@@ -35,24 +35,26 @@
 	<string>bitchat uses Bluetooth to create a secure mesh network for chatting with nearby users.</string>
 	<key>NSBluetoothPeripheralUsageDescription</key>
 	<string>bitchat uses Bluetooth to discover and connect with other bitchat users nearby.</string>
+	<key>NSCameraUsageDescription</key>
+	<string>bitchat uses the camera to scan QR codes to verify peers.</string>
+	<key>NSPhotoLibraryUsageDescription</key>
+	<string>bitchat lets you pick images from your photo library to share with nearby peers.</string>
+	<key>NSMicrophoneUsageDescription</key>
+	<string>bitchat uses the microphone to record voice notes that relay across the mesh.</string>
+	<key>NSLocationWhenInUseUsageDescription</key>
+	<string>bitchat uses your approximate location to compute local geohash channels for optional public chats. Exact GPS is never shared.</string>
 	<key>UIBackgroundModes</key>
 	<array>
 		<string>bluetooth-central</string>
 		<string>bluetooth-peripheral</string>
-		<string>remote-notification</string>
 	</array>
 	<key>UILaunchStoryboardName</key>
 	<string>LaunchScreen</string>
+	<key>UIRequiresFullScreen</key>
+	<true/>
 	<key>UISupportedInterfaceOrientations</key>
 	<array>
 		<string>UIInterfaceOrientationPortrait</string>
 	</array>
-	<key>UISupportedInterfaceOrientations~ipad</key>
-	<array>
-		<string>UIInterfaceOrientationLandscapeLeft</string>
-		<string>UIInterfaceOrientationLandscapeRight</string>
-		<string>UIInterfaceOrientationPortrait</string>
-		<string>UIInterfaceOrientationPortraitUpsideDown</string>
-	</array>
 </dict>
 </plist>

bitchat/LaunchScreen.storyboard

@@ -37,4 +37,4 @@
             <point key="canvasLocation" x="53" y="375"/>
         </scene>
     </scenes>
-</document>
+</document>

bitchat/Models/BitchatMessage.swift

@@ -0,0 +1,355 @@
+//
+// BitchatMessage.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+
+/// Represents a user-visible message in the BitChat system.
+/// Handles both broadcast messages and private encrypted messages,
+/// with support for mentions, replies, and delivery tracking.
+/// - Note: This is the primary data model for chat messages
+final class BitchatMessage: Codable {
+    let id: String
+    let sender: String
+    let content: String
+    let timestamp: Date
+    let isRelay: Bool
+    let originalSender: String?
+    let isPrivate: Bool
+    let recipientNickname: String?
+    let senderPeerID: PeerID?
+    let mentions: [String]?  // Array of mentioned nicknames
+    var deliveryStatus: DeliveryStatus? // Delivery tracking
+    
+    // Cached formatted text (not included in Codable)
+    private var _cachedFormattedText: [String: AttributedString] = [:]
+    
+    func getCachedFormattedText(isDark: Bool, isSelf: Bool) -> AttributedString? {
+        return _cachedFormattedText["\(isDark)-\(isSelf)"]
+    }
+    
+    func setCachedFormattedText(_ text: AttributedString, isDark: Bool, isSelf: Bool) {
+        _cachedFormattedText["\(isDark)-\(isSelf)"] = text
+    }
+    
+    // Codable implementation
+    enum CodingKeys: String, CodingKey {
+        case id, sender, content, timestamp, isRelay, originalSender
+        case isPrivate, recipientNickname, senderPeerID, mentions, deliveryStatus
+    }
+    
+    init(
+        id: String? = nil,
+        sender: String,
+        content: String,
+        timestamp: Date,
+        isRelay: Bool,
+        originalSender: String? = nil,
+        isPrivate: Bool = false,
+        recipientNickname: String? = nil,
+        senderPeerID: PeerID? = nil,
+        mentions: [String]? = nil,
+        deliveryStatus: DeliveryStatus? = nil
+    ) {
+        self.id = id ?? UUID().uuidString
+        self.sender = sender
+        self.content = content
+        self.timestamp = timestamp
+        self.isRelay = isRelay
+        self.originalSender = originalSender
+        self.isPrivate = isPrivate
+        self.recipientNickname = recipientNickname
+        self.senderPeerID = senderPeerID
+        self.mentions = mentions
+        self.deliveryStatus = deliveryStatus ?? (isPrivate ? .sending : nil)
+    }
+}
+
+// MARK: - Equatable Conformance
+
+extension BitchatMessage: Equatable {
+    static func == (lhs: BitchatMessage, rhs: BitchatMessage) -> Bool {
+        return lhs.id == rhs.id &&
+               lhs.sender == rhs.sender &&
+               lhs.content == rhs.content &&
+               lhs.timestamp == rhs.timestamp &&
+               lhs.isRelay == rhs.isRelay &&
+               lhs.originalSender == rhs.originalSender &&
+               lhs.isPrivate == rhs.isPrivate &&
+               lhs.recipientNickname == rhs.recipientNickname &&
+               lhs.senderPeerID == rhs.senderPeerID &&
+               lhs.mentions == rhs.mentions &&
+               lhs.deliveryStatus == rhs.deliveryStatus
+    }
+}
+
+// MARK: - Binary encoding
+
+extension BitchatMessage {
+    func toBinaryPayload() -> Data? {
+        var data = Data()
+        
+        // Message format:
+        // - Flags: 1 byte (bit 0: isRelay, bit 1: isPrivate, bit 2: hasOriginalSender, bit 3: hasRecipientNickname, bit 4: hasSenderPeerID, bit 5: hasMentions)
+        // - Timestamp: 8 bytes (seconds since epoch)
+        // - ID length: 1 byte
+        // - ID: variable
+        // - Sender length: 1 byte
+        // - Sender: variable
+        // - Content length: 2 bytes
+        // - Content: variable
+        // Optional fields based on flags:
+        // - Original sender length + data
+        // - Recipient nickname length + data
+        // - Sender peer ID length + data
+        // - Mentions array
+        
+        var flags: UInt8 = 0
+        if isRelay { flags |= 0x01 }
+        if isPrivate { flags |= 0x02 }
+        if originalSender != nil { flags |= 0x04 }
+        if recipientNickname != nil { flags |= 0x08 }
+        if senderPeerID != nil { flags |= 0x10 }
+        if mentions != nil && !mentions!.isEmpty { flags |= 0x20 }
+        
+        data.append(flags)
+        
+        // Timestamp (in milliseconds)
+        let timestampMillis = UInt64(timestamp.timeIntervalSince1970 * 1000)
+        // Encode as 8 bytes, big-endian
+        for i in (0..<8).reversed() {
+            data.append(UInt8((timestampMillis >> (i * 8)) & 0xFF))
+        }
+        
+        // ID
+        if let idData = id.data(using: .utf8) {
+            data.append(UInt8(min(idData.count, 255)))
+            data.append(idData.prefix(255))
+        } else {
+            data.append(0)
+        }
+        
+        // Sender
+        if let senderData = sender.data(using: .utf8) {
+            data.append(UInt8(min(senderData.count, 255)))
+            data.append(senderData.prefix(255))
+        } else {
+            data.append(0)
+        }
+        
+        // Content
+        if let contentData = content.data(using: .utf8) {
+            let length = UInt16(min(contentData.count, 65535))
+            // Encode length as 2 bytes, big-endian
+            data.append(UInt8((length >> 8) & 0xFF))
+            data.append(UInt8(length & 0xFF))
+            data.append(contentData.prefix(Int(length)))
+        } else {
+            data.append(contentsOf: [0, 0])
+        }
+        
+        // Optional fields
+        if let originalSender = originalSender, let origData = originalSender.data(using: .utf8) {
+            data.append(UInt8(min(origData.count, 255)))
+            data.append(origData.prefix(255))
+        }
+        
+        if let recipientNickname = recipientNickname, let recipData = recipientNickname.data(using: .utf8) {
+            data.append(UInt8(min(recipData.count, 255)))
+            data.append(recipData.prefix(255))
+        }
+        
+        if let peerData = senderPeerID?.id.data(using: .utf8) {
+            data.append(UInt8(min(peerData.count, 255)))
+            data.append(peerData.prefix(255))
+        }
+        
+        // Mentions array
+        if let mentions = mentions {
+            data.append(UInt8(min(mentions.count, 255))) // Number of mentions
+            for mention in mentions.prefix(255) {
+                if let mentionData = mention.data(using: .utf8) {
+                    data.append(UInt8(min(mentionData.count, 255)))
+                    data.append(mentionData.prefix(255))
+                } else {
+                    data.append(0)
+                }
+            }
+        }
+        
+        
+        return data
+    }
+    
+    convenience init?(_ data: Data) {
+        // Create an immutable copy to prevent threading issues
+        let dataCopy = Data(data)
+        
+        
+        guard dataCopy.count >= 13 else {
+            return nil
+        }
+        
+        var offset = 0
+        
+        // Flags
+        guard offset < dataCopy.count else {
+            return nil
+        }
+        let flags = dataCopy[offset]; offset += 1
+        let isRelay = (flags & 0x01) != 0
+        let isPrivate = (flags & 0x02) != 0
+        let hasOriginalSender = (flags & 0x04) != 0
+        let hasRecipientNickname = (flags & 0x08) != 0
+        let hasSenderPeerID = (flags & 0x10) != 0
+        let hasMentions = (flags & 0x20) != 0
+        
+        // Timestamp
+        guard offset + 8 <= dataCopy.count else {
+            return nil
+        }
+        let timestampData = dataCopy[offset..<offset+8]
+        let timestampMillis = timestampData.reduce(0) { result, byte in
+            (result << 8) | UInt64(byte)
+        }
+        offset += 8
+        let timestamp = Date(timeIntervalSince1970: TimeInterval(timestampMillis) / 1000.0)
+        
+        // ID
+        guard offset < dataCopy.count else {
+            return nil
+        }
+        let idLength = Int(dataCopy[offset]); offset += 1
+        guard offset + idLength <= dataCopy.count else {
+            return nil
+        }
+        let id = String(data: dataCopy[offset..<offset+idLength], encoding: .utf8) ?? UUID().uuidString
+        offset += idLength
+        
+        // Sender
+        guard offset < dataCopy.count else {
+            return nil
+        }
+        let senderLength = Int(dataCopy[offset]); offset += 1
+        guard offset + senderLength <= dataCopy.count else {
+            return nil
+        }
+        let sender = String(data: dataCopy[offset..<offset+senderLength], encoding: .utf8) ?? "unknown"
+        offset += senderLength
+        
+        // Content
+        guard offset + 2 <= dataCopy.count else {
+            return nil
+        }
+        let contentLengthData = dataCopy[offset..<offset+2]
+        let contentLength = Int(contentLengthData.reduce(0) { result, byte in
+            (result << 8) | UInt16(byte)
+        })
+        offset += 2
+        guard offset + contentLength <= dataCopy.count else {
+            return nil
+        }
+        
+        let content = String(data: dataCopy[offset..<offset+contentLength], encoding: .utf8) ?? ""
+        offset += contentLength
+        
+        // Optional fields
+        var originalSender: String?
+        if hasOriginalSender && offset < dataCopy.count {
+            let length = Int(dataCopy[offset]); offset += 1
+            if offset + length <= dataCopy.count {
+                originalSender = String(data: dataCopy[offset..<offset+length], encoding: .utf8)
+                offset += length
+            }
+        }
+        
+        var recipientNickname: String?
+        if hasRecipientNickname && offset < dataCopy.count {
+            let length = Int(dataCopy[offset]); offset += 1
+            if offset + length <= dataCopy.count {
+                recipientNickname = String(data: dataCopy[offset..<offset+length], encoding: .utf8)
+                offset += length
+            }
+        }
+        
+        var senderPeerID: PeerID?
+        if hasSenderPeerID && offset < dataCopy.count {
+            let length = Int(dataCopy[offset]); offset += 1
+            if offset + length <= dataCopy.count {
+                senderPeerID = PeerID(data: dataCopy[offset..<offset+length])
+                offset += length
+            }
+        }
+        
+        // Mentions array
+        var mentions: [String]?
+        if hasMentions && offset < dataCopy.count {
+            let mentionCount = Int(dataCopy[offset]); offset += 1
+            if mentionCount > 0 {
+                mentions = []
+                for _ in 0..<mentionCount {
+                    if offset < dataCopy.count {
+                        let length = Int(dataCopy[offset]); offset += 1
+                        if offset + length <= dataCopy.count {
+                            if let mention = String(data: dataCopy[offset..<offset+length], encoding: .utf8) {
+                                mentions?.append(mention)
+                            }
+                            offset += length
+                        }
+                    }
+                }
+            }
+        }
+        
+        self.init(
+            id: id,
+            sender: sender,
+            content: content,
+            timestamp: timestamp,
+            isRelay: isRelay,
+            originalSender: originalSender,
+            isPrivate: isPrivate,
+            recipientNickname: recipientNickname,
+            senderPeerID: senderPeerID,
+            mentions: mentions
+        )
+    }
+}
+
+// MARK: - Helpers
+
+extension BitchatMessage {
+    
+    private static let timestampFormatter: DateFormatter = {
+        let formatter = DateFormatter()
+        formatter.dateFormat = "HH:mm:ss"
+        return formatter
+    }()
+    
+    var formattedTimestamp: String {
+        Self.timestampFormatter.string(from: timestamp)
+    }
+}
+
+extension Array where Element == BitchatMessage {
+    /// Filters out empty ones and deduplicate by ID while preserving order (from oldest to newest)
+    func cleanedAndDeduped() -> [Element] {
+        let arr = filter { $0.content.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty == false }
+        guard arr.count > 1 else {
+            return arr
+        }
+        var seen = Set<String>()
+        var dedup: [BitchatMessage] = []
+        for m in arr.sorted(by: { $0.timestamp < $1.timestamp }) {
+            if !seen.contains(m.id) {
+                dedup.append(m)
+                seen.insert(m.id)
+            }
+        }
+        return dedup
+    }
+}

bitchat/Models/BitchatPacket.swift

@@ -0,0 +1,96 @@
+//
+// BitchatPacket.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+
+/// The core packet structure for all BitChat protocol messages.
+/// Encapsulates all data needed for routing through the mesh network,
+/// including TTL for hop limiting and optional encryption.
+/// - Note: Packets larger than BLE MTU (512 bytes) are automatically fragmented
+struct BitchatPacket: Codable {
+    let version: UInt8
+    let type: UInt8
+    let senderID: Data
+    let recipientID: Data?
+    let timestamp: UInt64
+    let payload: Data
+    var signature: Data?
+    var ttl: UInt8
+    var route: [Data]?
+    
+    init(type: UInt8, senderID: Data, recipientID: Data?, timestamp: UInt64, payload: Data, signature: Data?, ttl: UInt8, version: UInt8 = 1, route: [Data]? = nil) {
+        self.version = version
+        self.type = type
+        self.senderID = senderID
+        self.recipientID = recipientID
+        self.timestamp = timestamp
+        self.payload = payload
+        self.signature = signature
+        self.ttl = ttl
+        self.route = route
+    }
+    
+    // Convenience initializer for new binary format
+    init(type: UInt8, ttl: UInt8, senderID: PeerID, payload: Data) {
+        self.version = 1
+        self.type = type
+        // Convert hex string peer ID to binary data (8 bytes)
+        var senderData = Data()
+        var tempID = senderID.id
+        while tempID.count >= 2 {
+            let hexByte = String(tempID.prefix(2))
+            if let byte = UInt8(hexByte, radix: 16) {
+                senderData.append(byte)
+            }
+            tempID = String(tempID.dropFirst(2))
+        }
+        self.senderID = senderData
+        self.recipientID = nil
+        self.timestamp = UInt64(Date().timeIntervalSince1970 * 1000) // milliseconds
+        self.payload = payload
+        self.signature = nil
+        self.ttl = ttl
+        self.route = nil
+    }
+    
+    var data: Data? {
+        BinaryProtocol.encode(self)
+    }
+    
+    func toBinaryData(padding: Bool = true) -> Data? {
+        BinaryProtocol.encode(self, padding: padding)
+    }
+
+    // Backward-compatible helper (defaults to padded encoding)
+    func toBinaryData() -> Data? {
+        toBinaryData(padding: true)
+    }
+    
+    /// Create binary representation for signing (without signature and TTL fields)
+    /// TTL is excluded because it changes during packet relay operations
+    func toBinaryDataForSigning() -> Data? {
+        // Create a copy without signature and with fixed TTL for signing
+        // TTL must be excluded because it changes during relay
+        let unsignedPacket = BitchatPacket(
+            type: type,
+            senderID: senderID,
+            recipientID: recipientID,
+            timestamp: timestamp,
+            payload: payload,
+            signature: nil, // Remove signature for signing
+            ttl: 0, // Use fixed TTL=0 for signing to ensure relay compatibility
+            version: version,
+            route: route
+        )
+        return BinaryProtocol.encode(unsignedPacket)
+    }
+    
+    static func from(_ data: Data) -> BitchatPacket? {
+        BinaryProtocol.decode(data)
+    }
+}

bitchat/Models/BitchatPeer.swift

@@ -0,0 +1,98 @@
+import Foundation
+import CoreBluetooth
+
+/// Represents a peer in the BitChat network with all associated metadata
+struct BitchatPeer: Equatable {
+    let peerID: PeerID // Hex-encoded peer ID
+    let noisePublicKey: Data
+    let nickname: String
+    let lastSeen: Date
+    let isConnected: Bool
+    let isReachable: Bool
+    
+    // Favorite-related properties
+    var favoriteStatus: FavoritesPersistenceService.FavoriteRelationship?
+    
+    // Nostr identity (if known)
+    var nostrPublicKey: String?
+    
+    // Connection state
+    enum ConnectionState {
+        case bluetoothConnected
+        case meshReachable      // Seen via mesh recently, not directly connected
+        case nostrAvailable     // Mutual favorite, reachable via Nostr
+        case offline            // Not connected via any transport
+    }
+    
+    var connectionState: ConnectionState {
+        if isConnected {
+            return .bluetoothConnected
+        } else if isReachable {
+            return .meshReachable
+        } else if favoriteStatus?.isMutual == true {
+            // Mutual favorites can communicate via Nostr when offline
+            return .nostrAvailable
+        } else {
+            return .offline
+        }
+    }
+    
+    var isFavorite: Bool {
+        favoriteStatus?.isFavorite ?? false
+    }
+    
+    var isMutualFavorite: Bool {
+        favoriteStatus?.isMutual ?? false
+    }
+    
+    var theyFavoritedUs: Bool {
+        favoriteStatus?.theyFavoritedUs ?? false
+    }
+    
+    // Display helpers
+    var displayName: String {
+        nickname.isEmpty ? String(peerID.id.prefix(8)) : nickname
+    }
+    
+    var statusIcon: String {
+        switch connectionState {
+        case .bluetoothConnected:
+            return "📻" // Radio icon for mesh connection
+        case .meshReachable:
+            return "📡" // Antenna for mesh reachable
+        case .nostrAvailable:
+            return "🌐" // Purple globe for Nostr
+        case .offline:
+            if theyFavoritedUs && !isFavorite {
+                return "🌙" // Crescent moon - they favorited us but we didn't reciprocate
+            } else {
+                return ""
+            }
+        }
+    }
+    
+    // Initialize from mesh service data
+    init(
+        peerID: PeerID,
+        noisePublicKey: Data,
+        nickname: String,
+        lastSeen: Date = Date(),
+        isConnected: Bool = false,
+        isReachable: Bool = false
+    ) {
+        self.peerID = peerID
+        self.noisePublicKey = noisePublicKey
+        self.nickname = nickname
+        self.lastSeen = lastSeen
+        self.isConnected = isConnected
+        self.isReachable = isReachable
+        
+        // Load favorite status - will be set later by the manager
+        self.favoriteStatus = nil
+        self.nostrPublicKey = nil
+    }
+    
+    static func == (lhs: BitchatPeer, rhs: BitchatPeer) -> Bool {
+        lhs.peerID == rhs.peerID
+    }
+}

bitchat/Models/CommandInfo.swift

@@ -0,0 +1,58 @@
+//
+// CommandsInfo.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+
+// MARK: - CommandInfo Enum
+
+enum CommandInfo: String, Identifiable {
+    case block
+    case clear
+    case hug
+    case message = "dm"
+    case slap
+    case unblock
+    case who
+    case favorite
+    case unfavorite
+    
+    var id: String { rawValue }
+    
+    var alias: String { "/" + rawValue }
+    
+    var placeholder: String? {
+        switch self {
+        case .block, .hug, .message, .slap, .unblock, .favorite, .unfavorite:
+            return "<" + String(localized: "content.input.nickname_placeholder") + ">"
+        case .clear, .who:
+            return nil
+        }
+    }
+    
+    var description: String {
+        switch self {
+        case .block:        String(localized: "content.commands.block")
+        case .clear:        String(localized: "content.commands.clear")
+        case .hug:          String(localized: "content.commands.hug")
+        case .message:      String(localized: "content.commands.message")
+        case .slap:         String(localized: "content.commands.slap")
+        case .unblock:      String(localized: "content.commands.unblock")
+        case .who:          String(localized: "content.commands.who")
+        case .favorite:     String(localized: "content.commands.favorite")
+        case .unfavorite:   String(localized: "content.commands.unfavorite")
+        }
+    }
+    
+    static func all(isGeoPublic: Bool, isGeoDM: Bool) -> [CommandInfo] {
+        let baseCommands: [CommandInfo] = [.block, .unblock, .clear, .hug, .message, .slap, .who]
+        if isGeoPublic || isGeoDM {
+            return baseCommands + [.favorite, .unfavorite]
+        }
+        return baseCommands
+    }
+}

bitchat/Models/MessagePadding.swift

@@ -0,0 +1,61 @@
+//
+// MessagePadding.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+
+/// Provides privacy-preserving message padding to obscure actual content length.
+/// Uses PKCS#7-style padding with random bytes to prevent traffic analysis.
+struct MessagePadding {
+    // Standard block sizes for padding
+    static let blockSizes = [256, 512, 1024, 2048]
+    
+    // Add PKCS#7-style padding to reach target size
+    static func pad(_ data: Data, toSize targetSize: Int) -> Data {
+        guard data.count < targetSize else { return data }
+        
+        let paddingNeeded = targetSize - data.count
+        // Constrain to 255 to fit a single-byte pad length marker
+        guard paddingNeeded > 0 && paddingNeeded <= 255 else { return data }
+        
+        var padded = data
+        // PKCS#7: All pad bytes are equal to the pad length
+        padded.append(contentsOf: Array(repeating: UInt8(paddingNeeded), count: paddingNeeded))
+        return padded
+    }
+    
+    // Remove padding from data
+    static func unpad(_ data: Data) -> Data {
+        guard !data.isEmpty else { return data }
+        let last = data.last!
+        let paddingLength = Int(last)
+        // Must have at least 1 pad byte and not exceed data length
+        guard paddingLength > 0 && paddingLength <= data.count else { return data }
+        // Verify PKCS#7: all last N bytes equal to pad length
+        let start = data.count - paddingLength
+        let tail = data[start...]
+        for b in tail { if b != last { return data } }
+        return Data(data[..<start])
+    }
+    
+    // Find optimal block size for data
+    static func optimalBlockSize(for dataSize: Int) -> Int {
+        // Account for encryption overhead (~16 bytes for AES-GCM tag)
+        let totalSize = dataSize + 16
+        
+        // Find smallest block that fits
+        for blockSize in blockSizes {
+            if totalSize <= blockSize {
+                return blockSize
+            }
+        }
+        
+        // For very large messages, just use the original size
+        // (will be fragmented anyway)
+        return dataSize
+    }
+}

bitchat/Models/NoisePayload.swift

@@ -0,0 +1,41 @@
+//
+// NoisePayload.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+
+/// Helper to create typed Noise payloads
+struct NoisePayload {
+    let type: NoisePayloadType
+    let data: Data
+    
+    /// Encode payload with type prefix
+    func encode() -> Data {
+        var encoded = Data()
+        encoded.append(type.rawValue)
+        encoded.append(data)
+        return encoded
+    }
+    
+    /// Decode payload from data
+    static func decode(_ data: Data) -> NoisePayload? {
+        // Ensure we have at least 1 byte for the type
+        guard !data.isEmpty else {
+            return nil
+        }
+        
+        // Safely get the first byte
+        let firstByte = data[data.startIndex]
+        guard let type = NoisePayloadType(rawValue: firstByte) else {
+            return nil
+        }
+        
+        // Create a proper Data copy (not a subsequence) for thread safety
+        let payloadData = data.count > 1 ? Data(data.dropFirst()) : Data()
+        return NoisePayload(type: type, data: payloadData)
+    }
+}

bitchat/Models/PeerID.swift

@@ -0,0 +1,221 @@
+//
+// PeerID.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+
+struct PeerID: Equatable, Hashable {
+    enum Prefix: String, CaseIterable {
+        /// When no prefix is provided
+        case empty = ""
+        /// `"mesh:"`
+        case mesh = "mesh:"
+        /// `"name:"`
+        case name = "name:"
+        /// `"noise:"` (+ 64 characters hex)
+        case noise = "noise:"
+        /// `"nostr_"` (+ 16 characters hex)
+        case geoDM = "nostr_"
+        /// `"nostr:"` (+ 8 characters hex)
+        case geoChat = "nostr:"
+    }
+    
+    let prefix: Prefix
+    
+    /// Returns the actual value without any prefix
+    let bare: String
+    
+    /// Returns the full `id` value by combining `(prefix + bare)`
+    var id: String { prefix.rawValue + bare }
+    
+    // Private so the callers have to go through a convenience init
+    private init(prefix: Prefix, bare: any StringProtocol) {
+        self.prefix = prefix
+        self.bare = String(bare).lowercased()
+    }
+}
+
+// MARK: - Convenience Inits
+
+extension PeerID {
+    /// Convenience init to create GeoDM PeerID by appending `"nostr_"` to the first 16 characters of `pubKey`
+    init(nostr_ pubKey: String) {
+        self.init(prefix: .geoDM, bare: pubKey.prefix(TransportConfig.nostrConvKeyPrefixLength))
+    }
+    
+    /// Convenience init to create GeoChat PeerID by appending `"nostr:"` to the first 8 characters of `pubKey`
+    init(nostr pubKey: String) {
+        self.init(prefix: .geoChat, bare: pubKey.prefix(TransportConfig.nostrShortKeyDisplayLength))
+    }
+    
+    /// Convenience init to create PeerID from String/Substring by splitting it into prefix and bare parts
+    init(str: any StringProtocol) {
+        if let prefix = Prefix.allCases.first(where: { $0 != .empty && str.hasPrefix($0.rawValue) }) {
+            self.init(prefix: prefix, bare: String(str).dropFirst(prefix.rawValue.count))
+        } else {
+            self.init(prefix: .empty, bare: str)
+        }
+    }
+    
+    /// Convenience init to handle `Optional<String>`
+    init?(str: (any StringProtocol)?) {
+        guard let str else { return nil }
+        self.init(str: str)
+    }
+    
+    /// Convenience init to create PeerID by converting Data to String
+    init?(data: Data) {
+        self.init(str: String(data: data, encoding: .utf8))
+    }
+    
+    /// Convenience init to "hide" hex-encoding implementation detail
+    init(hexData: Data) {
+        self.init(str: hexData.hexEncodedString())
+    }
+    
+    /// Convenience init to "hide" hex-encoding implementation detail
+    init?(hexData: Data?) {
+        guard let hexData else { return nil }
+        self.init(hexData: hexData)
+    }
+}
+
+// MARK: - Noise Public Key Helpers
+
+extension PeerID {
+    /// Derive the stable 16-hex peer ID from a Noise static public key
+    init(publicKey: Data) {
+        self.init(str: publicKey.sha256Fingerprint().prefix(16))
+    }
+    
+    /// Returns a 16-hex short peer ID derived from a 64-hex Noise public key if needed
+    func toShort() -> PeerID {
+        if let noiseKey {
+            return PeerID(publicKey: noiseKey)
+        }
+        return self
+    }
+}
+
+// MARK: - Codable
+
+extension PeerID: Codable {
+    init(from decoder: any Decoder) throws {
+        self.init(str: try decoder.singleValueContainer().decode(String.self))
+    }
+    
+    func encode(to encoder: any Encoder) throws {
+        var container = encoder.singleValueContainer()
+        try container.encode(id)
+    }
+}
+
+// MARK: - Helpers
+
+extension PeerID {
+    var isEmpty: Bool {
+        id.isEmpty
+    }
+    
+    /// Returns true if `id` starts with "`nostr:`"
+    var isGeoChat: Bool {
+        prefix == .geoChat
+    }
+    
+    /// Returns true if `id` starts with "`nostr_`"
+    var isGeoDM: Bool {
+        prefix == .geoDM
+    }
+    
+    func toPercentEncoded() -> String {
+        id.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed) ?? id
+    }
+}
+
+extension PeerID {
+    var routingData: Data? {
+        if let direct = Data(hexString: id), direct.count == 8 { return direct }
+        if let bareData = Data(hexString: bare), bareData.count == 8 { return bareData }
+        let short = toShort()
+        return Data(hexString: short.id)
+    }
+
+    init?(routingData: Data) {
+        guard routingData.count == 8 else { return nil }
+        self.init(hexData: routingData)
+    }
+}
+
+// MARK: - Validation
+
+extension PeerID {
+    private enum Constants {
+        static let maxIDLength = 64
+        static let hexIDLength = 16 // 8 bytes = 16 hex chars
+    }
+    
+    /// Validates a peer ID from any source (short 16-hex, full 64-hex, or internal alnum/-/_ up to 64)
+    var isValid: Bool {
+        if prefix != .empty {
+            return PeerID(str: bare).isValid
+        }
+        
+        // Accept short routing IDs (exact 16-hex) or Full Noise key hex (exact 64-hex)
+        if isShort || isNoiseKeyHex {
+            return true
+        }
+        
+        // If length equals short or full but isn't valid hex, reject
+        if id.count == Constants.hexIDLength || id.count == Constants.maxIDLength {
+            return false
+        }
+        
+        // Internal format: alphanumeric + dash/underscore up to 63 (not 16 or 64)
+        let validCharset = CharacterSet.alphanumerics.union(CharacterSet(charactersIn: "-_"))
+        return !id.isEmpty &&
+                id.count < Constants.maxIDLength &&
+                id.rangeOfCharacter(from: validCharset.inverted) == nil
+    }
+    
+    /// Returns true if the `bare` id is all hex
+    var isHex: Bool {
+        bare.allSatisfy { $0.isHexDigit }
+    }
+    
+    /// Short routing IDs (exact 16-hex)
+    var isShort: Bool {
+        bare.count == Constants.hexIDLength && isHex
+    }
+    
+    /// Full Noise key hex (exact 64-hex)
+    var isNoiseKeyHex: Bool {
+        noiseKey != nil
+    }
+    
+    /// Full Noise key (exact 64-hex) as Data
+    var noiseKey: Data? {
+        guard bare.count == Constants.maxIDLength else { return nil }
+        return Data(hexString: bare)
+    }
+}
+
+// MARK: - Comparable
+
+extension PeerID: Comparable {
+    static func < (lhs: PeerID, rhs: PeerID) -> Bool {
+        lhs.id < rhs.id
+    }
+}
+
+// MARK: - CustomStringConvertible
+
+extension PeerID: CustomStringConvertible {
+    /// So it returns the actual `id` like before even inside another String
+    var description: String {
+        id
+    }
+}

bitchat/Models/ReadReceipt.swift

@@ -0,0 +1,95 @@
+//
+// ReadReceipt.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+
+struct ReadReceipt: Codable {
+    let originalMessageID: String
+    let receiptID: String
+    var readerID: PeerID  // Who read it
+    let readerNickname: String
+    let timestamp: Date
+    
+    init(originalMessageID: String, readerID: PeerID, readerNickname: String) {
+        self.originalMessageID = originalMessageID
+        self.receiptID = UUID().uuidString
+        self.readerID = readerID
+        self.readerNickname = readerNickname
+        self.timestamp = Date()
+    }
+    
+    // For binary decoding
+    private init(originalMessageID: String, receiptID: String, readerID: PeerID, readerNickname: String, timestamp: Date) {
+        self.originalMessageID = originalMessageID
+        self.receiptID = receiptID
+        self.readerID = readerID
+        self.readerNickname = readerNickname
+        self.timestamp = timestamp
+    }
+    
+    func encode() -> Data? {
+        try? JSONEncoder().encode(self)
+    }
+    
+    static func decode(from data: Data) -> ReadReceipt? {
+        try? JSONDecoder().decode(ReadReceipt.self, from: data)
+    }
+    
+    // MARK: - Binary Encoding
+    
+    func toBinaryData() -> Data {
+        var data = Data()
+        data.appendUUID(originalMessageID)
+        data.appendUUID(receiptID)
+        // ReaderID as 8-byte hex string
+        var readerData = Data()
+        var tempID = readerID.id
+        while tempID.count >= 2 && readerData.count < 8 {
+            let hexByte = String(tempID.prefix(2))
+            if let byte = UInt8(hexByte, radix: 16) {
+                readerData.append(byte)
+            }
+            tempID = String(tempID.dropFirst(2))
+        }
+        while readerData.count < 8 {
+            readerData.append(0)
+        }
+        data.append(readerData)
+        data.appendDate(timestamp)
+        data.appendString(readerNickname)
+        return data
+    }
+    
+    static func fromBinaryData(_ data: Data) -> ReadReceipt? {
+        // Create defensive copy
+        let dataCopy = Data(data)
+        
+        // Minimum size: 2 UUIDs (32) + readerID (8) + timestamp (8) + min nickname
+        guard dataCopy.count >= 49 else { return nil }
+        
+        var offset = 0
+        
+        guard let originalMessageID = dataCopy.readUUID(at: &offset),
+              let receiptID = dataCopy.readUUID(at: &offset) else { return nil }
+        
+        guard let readerIDData = dataCopy.readFixedBytes(at: &offset, count: 8) else { return nil }
+        let readerID = PeerID(hexData: readerIDData)
+        guard readerID.isValid else { return nil }
+        
+        guard let timestamp = dataCopy.readDate(at: &offset),
+              InputValidator.validateTimestamp(timestamp),
+              let readerNicknameRaw = dataCopy.readString(at: &offset),
+              let readerNickname = InputValidator.validateNickname(readerNicknameRaw) else { return nil }
+        
+        return ReadReceipt(originalMessageID: originalMessageID,
+                          receiptID: receiptID,
+                          readerID: readerID,
+                          readerNickname: readerNickname,
+                          timestamp: timestamp)
+    }
+}

bitchat/Models/RequestSyncPacket.swift

@@ -0,0 +1,79 @@
+import Foundation
+
+// REQUEST_SYNC payload TLV (type, length16, value)
+//  - 0x01: P (uint8) — Golomb-Rice parameter
+//  - 0x02: M (uint32, big-endian) — hash range (N * 2^P)
+//  - 0x03: data (opaque) — GR bitstream bytes (MSB-first)
+struct RequestSyncPacket {
+    let p: Int
+    let m: UInt32
+    let data: Data
+    let types: SyncTypeFlags?
+
+    init(p: Int, m: UInt32, data: Data, types: SyncTypeFlags? = nil) {
+        self.p = p
+        self.m = m
+        self.data = data
+        self.types = types
+    }
+
+    func encode() -> Data {
+        var out = Data()
+        func putTLV(_ t: UInt8, _ v: Data) {
+            out.append(t)
+            let len = UInt16(v.count)
+            out.append(UInt8((len >> 8) & 0xFF))
+            out.append(UInt8(len & 0xFF))
+            out.append(v)
+        }
+        // P
+        putTLV(0x01, Data([UInt8(p & 0xFF)]))
+        // M (uint32)
+        var mBE = m.bigEndian
+        putTLV(0x02, withUnsafeBytes(of: &mBE) { Data($0) })
+        // data
+        putTLV(0x03, data)
+        if let typesData = types?.toData() {
+            putTLV(0x04, typesData)
+        }
+        return out
+    }
+
+    static func decode(from data: Data, maxAcceptBytes: Int = 1024) -> RequestSyncPacket? {
+        var off = 0
+        var p: Int? = nil
+        var m: UInt32? = nil
+        var payload: Data? = nil
+        var types: SyncTypeFlags? = nil
+
+        while off + 3 <= data.count {
+            let t = Int(data[off]); off += 1
+            guard off + 2 <= data.count else { return nil }
+            let len = (Int(data[off]) << 8) | Int(data[off+1]); off += 2
+            guard off + len <= data.count else { return nil }
+            let v = data.subdata(in: off..<(off+len)); off += len
+            switch t {
+            case 0x01:
+                if v.count == 1 { p = Int(v[0]) }
+            case 0x02:
+                if v.count == 4 {
+                    var mm: UInt32 = 0
+                    for b in v { mm = (mm << 8) | UInt32(b) }
+                    m = mm
+                }
+            case 0x03:
+                if v.count > maxAcceptBytes { return nil }
+                payload = v
+            case 0x04:
+                if let decoded = SyncTypeFlags.decode(v) {
+                    types = decoded
+                }
+            default:
+                break // forward compatible; ignore unknown TLVs
+            }
+        }
+
+        guard let pp = p, let mm = m, let dd = payload, pp >= 1, mm > 0 else { return nil }
+        return RequestSyncPacket(p: pp, m: mm, data: dd, types: types)
+    }
+}

bitchat/Noise/NoiseHandshakeCoordinator.swift

@@ -1,342 +0,0 @@
-//
-// NoiseHandshakeCoordinator.swift
-// bitchat
-//
-// This is free and unencumbered software released into the public domain.
-// For more information, see <https://unlicense.org>
-//
-
-import Foundation
-
-/// Coordinates Noise handshakes to prevent race conditions and ensure reliable encryption establishment
-class NoiseHandshakeCoordinator {
-    
-    // MARK: - Handshake State
-    
-    enum HandshakeState: Equatable {
-        case idle
-        case waitingToInitiate(since: Date)
-        case initiating(attempt: Int, lastAttempt: Date)
-        case responding(since: Date)
-        case waitingForResponse(messagesSent: [Data], timeout: Date)
-        case established(since: Date)
-        case failed(reason: String, canRetry: Bool, lastAttempt: Date)
-        
-        var isActive: Bool {
-            switch self {
-            case .idle, .established, .failed:
-                return false
-            default:
-                return true
-            }
-        }
-    }
-    
-    // MARK: - Properties
-    
-    private var handshakeStates: [String: HandshakeState] = [:]
-    private var handshakeQueue = DispatchQueue(label: "chat.bitchat.noise.handshake", attributes: .concurrent)
-    
-    // Configuration
-    private let maxHandshakeAttempts = 3
-    private let handshakeTimeout: TimeInterval = 10.0
-    private let retryDelay: TimeInterval = 2.0
-    private let minTimeBetweenHandshakes: TimeInterval = 1.0 // Reduced from 5.0 for faster recovery
-    
-    // Track handshake messages to detect duplicates
-    private var processedHandshakeMessages: Set<Data> = []
-    private let messageHistoryLimit = 100
-    
-    // MARK: - Role Determination
-    
-    /// Deterministically determine who should initiate the handshake
-    /// Lower peer ID becomes the initiator to prevent simultaneous attempts
-    func determineHandshakeRole(myPeerID: String, remotePeerID: String) -> NoiseRole {
-        // Use simple string comparison for deterministic ordering
-        return myPeerID < remotePeerID ? .initiator : .responder
-    }
-    
-    /// Check if we should initiate handshake with a peer
-    func shouldInitiateHandshake(myPeerID: String, remotePeerID: String, forceIfStale: Bool = false) -> Bool {
-        return handshakeQueue.sync {
-            // Check if we're already in an active handshake
-            if let state = handshakeStates[remotePeerID], state.isActive {
-                // Check if the handshake is stale and we should force a new one
-                if forceIfStale {
-                    switch state {
-                    case .initiating(_, let lastAttempt):
-                        if Date().timeIntervalSince(lastAttempt) > handshakeTimeout {
-                            SecureLogger.log("Forcing new handshake with \(remotePeerID) - previous stuck in initiating", 
-                                           category: SecureLogger.handshake, level: .warning)
-                            return true
-                        }
-                    default:
-                        break
-                    }
-                }
-                
-                SecureLogger.log("Already in active handshake with \(remotePeerID), state: \(state)", 
-                               category: SecureLogger.handshake, level: .debug)
-                return false
-            }
-            
-            // Check role
-            let role = determineHandshakeRole(myPeerID: myPeerID, remotePeerID: remotePeerID)
-            if role != .initiator {
-                SecureLogger.log("Not initiator for handshake with \(remotePeerID) (my: \(myPeerID), their: \(remotePeerID))", 
-                               category: SecureLogger.handshake, level: .debug)
-                return false
-            }
-            
-            // Check if we've failed recently and can't retry yet
-            if case .failed(_, let canRetry, let lastAttempt) = handshakeStates[remotePeerID] {
-                if !canRetry {
-                    return false
-                }
-                if Date().timeIntervalSince(lastAttempt) < retryDelay {
-                    return false
-                }
-            }
-            
-            return true
-        }
-    }
-    
-    /// Record that we're initiating a handshake
-    func recordHandshakeInitiation(peerID: String) {
-        handshakeQueue.async(flags: .barrier) {
-            let attempt = self.getCurrentAttempt(for: peerID) + 1
-            self.handshakeStates[peerID] = .initiating(attempt: attempt, lastAttempt: Date())
-            SecureLogger.log("Recording handshake initiation with \(peerID), attempt \(attempt)", 
-                           category: SecureLogger.handshake, level: .info)
-        }
-    }
-    
-    /// Record that we're responding to a handshake
-    func recordHandshakeResponse(peerID: String) {
-        handshakeQueue.async(flags: .barrier) {
-            self.handshakeStates[peerID] = .responding(since: Date())
-            SecureLogger.log("Recording handshake response to \(peerID)", 
-                           category: SecureLogger.handshake, level: .info)
-        }
-    }
-    
-    /// Record successful handshake completion
-    func recordHandshakeSuccess(peerID: String) {
-        handshakeQueue.async(flags: .barrier) {
-            self.handshakeStates[peerID] = .established(since: Date())
-            SecureLogger.log("Handshake successfully established with \(peerID)", 
-                           category: SecureLogger.handshake, level: .info)
-        }
-    }
-    
-    /// Record handshake failure
-    func recordHandshakeFailure(peerID: String, reason: String) {
-        handshakeQueue.async(flags: .barrier) {
-            let attempts = self.getCurrentAttempt(for: peerID)
-            let canRetry = attempts < self.maxHandshakeAttempts
-            self.handshakeStates[peerID] = .failed(reason: reason, canRetry: canRetry, lastAttempt: Date())
-            SecureLogger.log("Handshake failed with \(peerID): \(reason), canRetry: \(canRetry)", 
-                           category: SecureLogger.handshake, level: .warning)
-        }
-    }
-    
-    /// Check if we should accept an incoming handshake initiation
-    func shouldAcceptHandshakeInitiation(myPeerID: String, remotePeerID: String) -> Bool {
-        return handshakeQueue.sync {
-            // If we're already established, reject new handshakes
-            if case .established = handshakeStates[remotePeerID] {
-                SecureLogger.log("Rejecting handshake from \(remotePeerID) - already established", 
-                               category: SecureLogger.handshake, level: .debug)
-                return false
-            }
-            
-            let role = determineHandshakeRole(myPeerID: myPeerID, remotePeerID: remotePeerID)
-            
-            // If we're the initiator and already initiating, this is a race condition
-            if role == .initiator {
-                if case .initiating = handshakeStates[remotePeerID] {
-                    // They shouldn't be initiating, but accept it to recover from race condition
-                    SecureLogger.log("Accepting handshake from \(remotePeerID) despite being initiator (race condition recovery)", 
-                                   category: SecureLogger.handshake, level: .warning)
-                    return true
-                }
-            }
-            
-            // If we're the responder, we should accept
-            return true
-        }
-    }
-    
-    /// Check if this is a duplicate handshake message
-    func isDuplicateHandshakeMessage(_ data: Data) -> Bool {
-        return handshakeQueue.sync {
-            if processedHandshakeMessages.contains(data) {
-                return true
-            }
-            
-            // Add to processed messages with size limit
-            if processedHandshakeMessages.count >= messageHistoryLimit {
-                processedHandshakeMessages.removeAll()
-            }
-            processedHandshakeMessages.insert(data)
-            return false
-        }
-    }
-    
-    /// Get time to wait before next handshake attempt
-    func getRetryDelay(for peerID: String) -> TimeInterval? {
-        return handshakeQueue.sync {
-            guard let state = handshakeStates[peerID] else { return nil }
-            
-            switch state {
-            case .failed(_, let canRetry, let lastAttempt):
-                if !canRetry { return nil }
-                let timeSinceFailure = Date().timeIntervalSince(lastAttempt)
-                if timeSinceFailure >= retryDelay {
-                    return 0
-                }
-                return retryDelay - timeSinceFailure
-                
-            case .initiating(_, let lastAttempt):
-                let timeSinceAttempt = Date().timeIntervalSince(lastAttempt)
-                if timeSinceAttempt >= minTimeBetweenHandshakes {
-                    return 0
-                }
-                return minTimeBetweenHandshakes - timeSinceAttempt
-                
-            default:
-                return nil
-            }
-        }
-    }
-    
-    /// Reset handshake state for a peer
-    func resetHandshakeState(for peerID: String) {
-        handshakeQueue.async(flags: .barrier) {
-            self.handshakeStates.removeValue(forKey: peerID)
-            SecureLogger.log("Reset handshake state for \(peerID)", 
-                           category: SecureLogger.handshake, level: .debug)
-        }
-    }
-    
-    /// Clean up stale handshake states
-    func cleanupStaleHandshakes(staleTimeout: TimeInterval = 30.0) -> [String] {
-        return handshakeQueue.sync {
-            let now = Date()
-            var stalePeerIDs: [String] = []
-            
-            for (peerID, state) in handshakeStates {
-                var isStale = false
-                
-                switch state {
-                case .initiating(_, let lastAttempt):
-                    if now.timeIntervalSince(lastAttempt) > staleTimeout {
-                        isStale = true
-                    }
-                case .responding(let since):
-                    if now.timeIntervalSince(since) > staleTimeout {
-                        isStale = true
-                    }
-                case .waitingForResponse(_, let timeout):
-                    if now > timeout {
-                        isStale = true
-                    }
-                default:
-                    break
-                }
-                
-                if isStale {
-                    stalePeerIDs.append(peerID)
-                    SecureLogger.log("Found stale handshake state for \(peerID): \(state)", 
-                                   category: SecureLogger.handshake, level: .warning)
-                }
-            }
-            
-            // Clean up stale states
-            for peerID in stalePeerIDs {
-                handshakeStates.removeValue(forKey: peerID)
-            }
-            
-            return stalePeerIDs
-        }
-    }
-    
-    /// Get current handshake state
-    func getHandshakeState(for peerID: String) -> HandshakeState {
-        return handshakeQueue.sync {
-            return handshakeStates[peerID] ?? .idle
-        }
-    }
-    
-    /// Get current retry count for a peer
-    func getRetryCount(for peerID: String) -> Int {
-        return handshakeQueue.sync {
-            switch handshakeStates[peerID] {
-            case .initiating(let attempt, _):
-                return attempt - 1  // Attempts start at 1, retries start at 0
-            default:
-                return 0
-            }
-        }
-    }
-    
-    /// Increment retry count for a peer
-    func incrementRetryCount(for peerID: String) {
-        handshakeQueue.async(flags: .barrier) {
-            let currentAttempt = self.getCurrentAttempt(for: peerID)
-            self.handshakeStates[peerID] = .initiating(attempt: currentAttempt + 1, lastAttempt: Date())
-        }
-    }
-    
-    // MARK: - Private Helpers
-    
-    private func getCurrentAttempt(for peerID: String) -> Int {
-        switch handshakeStates[peerID] {
-        case .initiating(let attempt, _):
-            return attempt
-        case .failed(_, _, _):
-            // Count previous attempts
-            return 1 // Simplified for now
-        default:
-            return 0
-        }
-    }
-    
-    /// Log current handshake states for debugging
-    func logHandshakeStates() {
-        handshakeQueue.sync {
-            SecureLogger.log("=== Handshake States ===", category: SecureLogger.handshake, level: .debug)
-            for (peerID, state) in handshakeStates {
-                let stateDesc: String
-                switch state {
-                case .idle:
-                    stateDesc = "idle"
-                case .waitingToInitiate(let since):
-                    stateDesc = "waiting to initiate (since \(since))"
-                case .initiating(let attempt, let lastAttempt):
-                    stateDesc = "initiating (attempt \(attempt), last: \(lastAttempt))"
-                case .responding(let since):
-                    stateDesc = "responding (since: \(since))"
-                case .waitingForResponse(let messages, let timeout):
-                    stateDesc = "waiting for response (\(messages.count) messages, timeout: \(timeout))"
-                case .established(let since):
-                    stateDesc = "established (since \(since))"
-                case .failed(let reason, let canRetry, let lastAttempt):
-                    stateDesc = "failed: \(reason) (canRetry: \(canRetry), last: \(lastAttempt))"
-                }
-                SecureLogger.log("  \(peerID): \(stateDesc)", category: SecureLogger.handshake, level: .debug)
-            }
-            SecureLogger.log("========================", category: SecureLogger.handshake, level: .debug)
-        }
-    }
-    
-    /// Clear all handshake states - used during panic mode
-    func clearAllHandshakeStates() {
-        handshakeQueue.async(flags: .barrier) {
-            SecureLogger.log("Clearing all handshake states for panic mode", category: SecureLogger.handshake, level: .warning)
-            self.handshakeStates.removeAll()
-            self.processedHandshakeMessages.removeAll()
-        }
-    }
-}

bitchat/Noise/NoiseProtocol.swift

@@ -6,15 +6,88 @@
 // For more information, see <https://unlicense.org>
 //
 
+///
+/// # NoiseProtocol
+///
+/// A complete implementation of the Noise Protocol Framework for end-to-end
+/// encryption in BitChat. This file contains the core cryptographic primitives
+/// and handshake logic that enable secure communication between peers.
+///
+/// ## Overview
+/// The Noise Protocol Framework is a modern cryptographic framework designed
+/// for building secure protocols. BitChat uses Noise to provide:
+/// - Mutual authentication between peers
+/// - Forward secrecy for all messages
+/// - Protection against replay attacks
+/// - Minimal round trips for connection establishment
+///
+/// ## Implementation Details
+/// This implementation follows the Noise specification exactly, using:
+/// - **Pattern**: XX (most versatile, provides mutual authentication)
+/// - **DH**: Curve25519 (X25519 key exchange)
+/// - **Cipher**: ChaCha20-Poly1305 (AEAD encryption)
+/// - **Hash**: SHA-256 (for key derivation and authentication)
+///
+/// ## Security Properties
+/// The XX handshake pattern provides:
+/// 1. **Identity Hiding**: Both parties' identities are encrypted
+/// 2. **Forward Secrecy**: Past sessions remain secure if keys are compromised
+/// 3. **Key Compromise Impersonation Resistance**: Compromised static key doesn't allow impersonation to that party
+/// 4. **Mutual Authentication**: Both parties verify each other's identity
+///
+/// ## Handshake Flow (XX Pattern)
+/// ```
+/// Initiator                              Responder
+/// ---------                              ---------
+/// -> e                                   (ephemeral key)
+/// <- e, ee, s, es                       (ephemeral, DH, static encrypted, DH)
+/// -> s, se                              (static encrypted, DH)
+/// ```
+///
+/// ## Key Components
+/// - **NoiseCipherState**: Manages symmetric encryption with nonce tracking
+/// - **NoiseSymmetricState**: Handles key derivation and handshake hashing
+/// - **NoiseHandshakeState**: Orchestrates the complete handshake process
+///
+/// ## Replay Protection
+/// Implements sliding window replay protection to prevent message replay attacks:
+/// - Tracks nonces within a 1024-message window
+/// - Rejects duplicate or too-old nonces
+/// - Handles out-of-order message delivery
+///
+/// ## Usage Example
+/// ```swift
+/// let handshake = NoiseHandshakeState(
+///     pattern: .XX,
+///     role: .initiator,
+///     localStatic: staticKeyPair
+/// )
+/// let messageBuffer = handshake.writeMessage(payload: Data())
+/// // Send messageBuffer to peer...
+/// ```
+///
+/// ## Security Considerations
+/// - Static keys must be generated using secure random sources
+/// - Keys should be stored securely (e.g., in Keychain)
+/// - Handshake state must not be reused after completion
+/// - Transport messages have a nonce limit (2^64-1)
+///
+/// ## References
+/// - Noise Protocol Framework: http://www.noiseprotocol.org/
+/// - Noise Specification: http://www.noiseprotocol.org/noise.html
+///
+
+import BitLogger
 import Foundation
 import CryptoKit
-import os.log
 
 // Core Noise Protocol implementation
 // Based on the Noise Protocol Framework specification
 
 // MARK: - Constants and Types
 
+/// Supported Noise handshake patterns.
+/// Each pattern provides different security properties and authentication guarantees.
 enum NoisePattern {
     case XX  // Most versatile, mutual authentication
     case IK  // Initiator knows responder's static key
@@ -50,7 +123,11 @@ struct NoiseProtocolName {
 
 // MARK: - Cipher State
 
-class NoiseCipherState {
+/// Manages symmetric encryption state for Noise protocol sessions.
+/// Handles ChaCha20-Poly1305 AEAD encryption with automatic nonce management
+/// and replay protection using a sliding window algorithm.
+/// - Warning: Nonce reuse would be catastrophic for security
+final class NoiseCipherState {
     // Constants for replay protection
     private static let NONCE_SIZE_BYTES = 4
     private static let REPLAY_WINDOW_SIZE = 1024
@@ -72,6 +149,10 @@ class NoiseCipherState {
         self.useExtractedNonce = useExtractedNonce
     }
     
+    deinit {
+        clearSensitiveData()
+    }
+    
     func initializeKey(_ key: SymmetricKey) {
         self.key = key
         self.nonce = 0
@@ -204,7 +285,7 @@ class NoiseCipherState {
         
         // Log high nonce values that might indicate issues
         if currentNonce > Self.HIGH_NONCE_WARNING_THRESHOLD {
-            SecureLogger.log("High nonce value detected: \(currentNonce) - consider rekeying", category: SecureLogger.encryption, level: .warning)
+            SecureLogger.warning("High nonce value detected: \(currentNonce) - consider rekeying", category: .encryption)
         }
                 
         return combinedPayload
@@ -226,13 +307,13 @@ class NoiseCipherState {
         if useExtractedNonce {
             // Extract nonce and ciphertext from combined payload
             guard let (extractedNonce, actualCiphertext) = try extractNonceFromCiphertextPayload(ciphertext) else {
-                SecureLogger.log("Decrypt failed: Could not extract nonce from payload")
+                SecureLogger.debug("Decrypt failed: Could not extract nonce from payload")
                 throw NoiseError.invalidCiphertext
             }
             
             // Validate nonce with sliding window replay protection
             guard isValidNonce(extractedNonce) else {
-                SecureLogger.log("Replay attack detected: nonce \(extractedNonce) rejected")
+                SecureLogger.debug("Replay attack detected: nonce \(extractedNonce) rejected")
                 throw NoiseError.replayDetected
             }
 
@@ -261,7 +342,7 @@ class NoiseCipherState {
         
         // Log high nonce values that might indicate issues
         if decryptionNonce > Self.HIGH_NONCE_WARNING_THRESHOLD {
-            SecureLogger.log("High nonce value detected: \(decryptionNonce) - consider rekeying", category: SecureLogger.encryption, level: .warning)
+            SecureLogger.warning("High nonce value detected: \(decryptionNonce) - consider rekeying", category: .encryption)
         }
         
         do {
@@ -274,17 +355,36 @@ class NoiseCipherState {
             nonce += 1
             return plaintext
         } catch {
-            SecureLogger.log("Decrypt failed: \(error) for nonce \(decryptionNonce)")
+            SecureLogger.debug("Decrypt failed: \(error) for nonce \(decryptionNonce)")
             // Log authentication failures with nonce info
-            SecureLogger.log("Decryption failed at nonce \(decryptionNonce)", category: SecureLogger.encryption, level: .error)
+            SecureLogger.error("Decryption failed at nonce \(decryptionNonce)", category: .encryption)
             throw error
         }
     }
+    
+    /// Securely clear sensitive cryptographic data from memory
+    func clearSensitiveData() {
+        // Clear the symmetric key
+        key = nil
+        
+        // Reset nonce
+        nonce = 0
+        highestReceivedNonce = 0
+        
+        // Clear replay window
+        for i in 0..<replayWindow.count {
+            replayWindow[i] = 0
+        }
+    }
 }
 
 // MARK: - Symmetric State
 
-class NoiseSymmetricState {
+/// Manages the symmetric cryptographic state during Noise handshakes.
+/// Responsible for key derivation, protocol name hashing, and maintaining
+/// the chaining key that provides key separation between handshake messages.
+/// - Note: This class implements the SymmetricState object from the Noise spec
+final class NoiseSymmetricState {
     private var cipherState: NoiseCipherState
     private var chainingKey: Data
     private var hash: Data
@@ -297,7 +397,7 @@ class NoiseSymmetricState {
         if nameData.count <= 32 {
             self.hash = nameData + Data(repeating: 0, count: 32 - nameData.count)
         } else {
-            self.hash = Data(SHA256.hash(data: nameData))
+            self.hash = nameData.sha256Hash()
         }
         self.chainingKey = self.hash
     }
@@ -310,7 +410,7 @@ class NoiseSymmetricState {
     }
     
     func mixHash(_ data: Data) {
-        hash = Data(SHA256.hash(data: hash + data))
+        hash = (hash + data).sha256Hash()
     }
     
     func mixKeyAndHash(_ inputKeyMaterial: Data) {
@@ -384,9 +484,14 @@ class NoiseSymmetricState {
 
 // MARK: - Handshake State
 
-class NoiseHandshakeState {
+/// Orchestrates the complete Noise handshake process.
+/// This is the main interface for establishing encrypted sessions between peers.
+/// Manages the handshake state machine, message patterns, and key derivation.
+/// - Important: Each handshake instance should only be used once
+final class NoiseHandshakeState {
     private let role: NoiseRole
     private let pattern: NoisePattern
+    private let keychain: KeychainManagerProtocol
     private var symmetricState: NoiseSymmetricState
     
     // Keys
@@ -402,9 +507,16 @@ class NoiseHandshakeState {
     private var messagePatterns: [[NoiseMessagePattern]] = []
     private var currentPattern = 0
     
-    init(role: NoiseRole, pattern: NoisePattern, localStaticKey: Curve25519.KeyAgreement.PrivateKey? = nil, remoteStaticKey: Curve25519.KeyAgreement.PublicKey? = nil) {
+    init(
+        role: NoiseRole,
+        pattern: NoisePattern,
+        keychain: KeychainManagerProtocol,
+        localStaticKey: Curve25519.KeyAgreement.PrivateKey? = nil,
+        remoteStaticKey: Curve25519.KeyAgreement.PublicKey? = nil
+    ) {
         self.role = role
         self.pattern = pattern
+        self.keychain = keychain
         
         // Initialize static keys
         if let localKey = localStaticKey {
@@ -472,7 +584,10 @@ class NoiseHandshakeState {
                     throw NoiseError.missingKeys
                 }
                 let shared = try localEphemeral.sharedSecretFromKeyAgreement(with: remoteEphemeral)
-                symmetricState.mixKey(shared.withUnsafeBytes { Data($0) })
+                var sharedData = shared.withUnsafeBytes { Data($0) }
+                symmetricState.mixKey(sharedData)
+                // Clear sensitive shared secret
+                keychain.secureClear(&sharedData)
                 
             case .es:
                 // DH(ephemeral, static) - direction depends on role
@@ -517,7 +632,10 @@ class NoiseHandshakeState {
                     throw NoiseError.missingKeys
                 }
                 let shared = try localStatic.sharedSecretFromKeyAgreement(with: remoteStatic)
-                symmetricState.mixKey(shared.withUnsafeBytes { Data($0) })
+                var sharedData = shared.withUnsafeBytes { Data($0) }
+                symmetricState.mixKey(sharedData)
+                // Clear sensitive shared secret
+                keychain.secureClear(&sharedData)
             }
         }
         
@@ -551,7 +669,7 @@ class NoiseHandshakeState {
                 do {
                     remoteEphemeralPublic = try NoiseHandshakeState.validatePublicKey(ephemeralData)
                 } catch {
-                    SecureLogger.log("Invalid ephemeral public key received", category: SecureLogger.security, level: .warning)
+                    SecureLogger.warning("Invalid ephemeral public key received", category: .security)
                     throw NoiseError.invalidMessage
                 }
                 symmetricState.mixHash(ephemeralData)
@@ -568,7 +686,7 @@ class NoiseHandshakeState {
                     let decrypted = try symmetricState.decryptAndHash(staticData)
                     remoteStaticPublic = try NoiseHandshakeState.validatePublicKey(decrypted)
                 } catch {
-                    SecureLogger.logSecurityEvent(.authenticationFailed(peerID: "Unknown - handshake"), level: .error)
+                    SecureLogger.error(.authenticationFailed(peerID: "Unknown - handshake"))
                     throw NoiseError.authenticationFailure
                 }
                 
@@ -602,14 +720,20 @@ class NoiseHandshakeState {
                     throw NoiseError.missingKeys
                 }
                 let shared = try localEphemeral.sharedSecretFromKeyAgreement(with: remoteStatic)
-                symmetricState.mixKey(shared.withUnsafeBytes { Data($0) })
+                var sharedData = shared.withUnsafeBytes { Data($0) }
+                symmetricState.mixKey(sharedData)
+                // Clear sensitive shared secret
+                keychain.secureClear(&sharedData)
             } else {
                 guard let localStatic = localStaticPrivate,
                       let remoteEphemeral = remoteEphemeralPublic else {
                     throw NoiseError.missingKeys
                 }
                 let shared = try localStatic.sharedSecretFromKeyAgreement(with: remoteEphemeral)
-                symmetricState.mixKey(shared.withUnsafeBytes { Data($0) })
+                var sharedData = shared.withUnsafeBytes { Data($0) }
+                symmetricState.mixKey(sharedData)
+                // Clear sensitive shared secret
+                keychain.secureClear(&sharedData)
             }
             
         case .se:
@@ -619,14 +743,20 @@ class NoiseHandshakeState {
                     throw NoiseError.missingKeys
                 }
                 let shared = try localStatic.sharedSecretFromKeyAgreement(with: remoteEphemeral)
-                symmetricState.mixKey(shared.withUnsafeBytes { Data($0) })
+                var sharedData = shared.withUnsafeBytes { Data($0) }
+                symmetricState.mixKey(sharedData)
+                // Clear sensitive shared secret
+                keychain.secureClear(&sharedData)
             } else {
                 guard let localEphemeral = localEphemeralPrivate,
                       let remoteStatic = remoteStaticPublic else {
                     throw NoiseError.missingKeys
                 }
                 let shared = try localEphemeral.sharedSecretFromKeyAgreement(with: remoteStatic)
-                symmetricState.mixKey(shared.withUnsafeBytes { Data($0) })
+                var sharedData = shared.withUnsafeBytes { Data($0) }
+                symmetricState.mixKey(sharedData)
+                // Clear sensitive shared secret
+                keychain.secureClear(&sharedData)
             }
             
         case .ss:
@@ -637,7 +767,7 @@ class NoiseHandshakeState {
             let shared = try localStatic.sharedSecretFromKeyAgreement(with: remoteStatic)
             symmetricState.mixKey(shared.withUnsafeBytes { Data($0) })
             
-        default:
+        case .e, .s:
             break
         }
     }
@@ -755,7 +885,7 @@ extension NoiseHandshakeState {
         
         // Check against known bad points
         if lowOrderPoints.contains(keyData) {
-            SecureLogger.log("Low-order point detected", category: SecureLogger.security, level: .warning)
+            SecureLogger.warning("Low-order point detected", category: .security)
             throw NoiseError.invalidPublicKey
         }
         
@@ -765,7 +895,7 @@ extension NoiseHandshakeState {
             return publicKey
         } catch {
             // If CryptoKit rejects it, it's invalid
-            SecureLogger.log("CryptoKit validation failed", category: SecureLogger.security, level: .warning)
+            SecureLogger.warning("CryptoKit validation failed", category: .security)
             throw NoiseError.invalidPublicKey
         }
     }

bitchat/Noise/NoiseRateLimiter.swift

@@ -0,0 +1,95 @@
+//
+// NoiseRateLimiter.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import BitLogger
+import Foundation
+
+final class NoiseRateLimiter {
+    private var handshakeTimestamps: [PeerID: [Date]] = [:]
+    private var messageTimestamps: [PeerID: [Date]] = [:]
+    
+    // Global rate limiting
+    private var globalHandshakeTimestamps: [Date] = []
+    private var globalMessageTimestamps: [Date] = []
+    
+    private let queue = DispatchQueue(label: "chat.bitchat.noise.ratelimit", attributes: .concurrent)
+    
+    func allowHandshake(from peerID: PeerID) -> Bool {
+        return queue.sync(flags: .barrier) {
+            let now = Date()
+            let oneMinuteAgo = now.addingTimeInterval(-60)
+            
+            // Check global rate limit first
+            globalHandshakeTimestamps = globalHandshakeTimestamps.filter { $0 > oneMinuteAgo }
+            if globalHandshakeTimestamps.count >= NoiseSecurityConstants.maxGlobalHandshakesPerMinute {
+                SecureLogger.warning("Global handshake rate limit exceeded: \(globalHandshakeTimestamps.count)/\(NoiseSecurityConstants.maxGlobalHandshakesPerMinute) per minute", category: .security)
+                return false
+            }
+            
+            // Check per-peer rate limit
+            var timestamps = handshakeTimestamps[peerID] ?? []
+            timestamps = timestamps.filter { $0 > oneMinuteAgo }
+            
+            if timestamps.count >= NoiseSecurityConstants.maxHandshakesPerMinute {
+                SecureLogger.warning("Per-peer handshake rate limit exceeded for \(peerID): \(timestamps.count)/\(NoiseSecurityConstants.maxHandshakesPerMinute) per minute", category: .security)
+                return false
+            }
+            
+            // Record new handshake
+            timestamps.append(now)
+            handshakeTimestamps[peerID] = timestamps
+            globalHandshakeTimestamps.append(now)
+            return true
+        }
+    }
+    
+    func allowMessage(from peerID: PeerID) -> Bool {
+        return queue.sync(flags: .barrier) {
+            let now = Date()
+            let oneSecondAgo = now.addingTimeInterval(-1)
+            
+            // Check global rate limit first
+            globalMessageTimestamps = globalMessageTimestamps.filter { $0 > oneSecondAgo }
+            if globalMessageTimestamps.count >= NoiseSecurityConstants.maxGlobalMessagesPerSecond {
+                SecureLogger.warning("Global message rate limit exceeded: \(globalMessageTimestamps.count)/\(NoiseSecurityConstants.maxGlobalMessagesPerSecond) per second", category: .security)
+                return false
+            }
+            
+            // Check per-peer rate limit
+            var timestamps = messageTimestamps[peerID] ?? []
+            timestamps = timestamps.filter { $0 > oneSecondAgo }
+            
+            if timestamps.count >= NoiseSecurityConstants.maxMessagesPerSecond {
+                SecureLogger.warning("Per-peer message rate limit exceeded for \(peerID): \(timestamps.count)/\(NoiseSecurityConstants.maxMessagesPerSecond) per second", category: .security)
+                return false
+            }
+            
+            // Record new message
+            timestamps.append(now)
+            messageTimestamps[peerID] = timestamps
+            globalMessageTimestamps.append(now)
+            return true
+        }
+    }
+    
+    func reset(for peerID: PeerID) {
+        queue.async(flags: .barrier) {
+            self.handshakeTimestamps.removeValue(forKey: peerID)
+            self.messageTimestamps.removeValue(forKey: peerID)
+        }
+    }
+
+    func resetAll() {
+        queue.async(flags: .barrier) {
+            self.handshakeTimestamps.removeAll()
+            self.messageTimestamps.removeAll()
+            self.globalHandshakeTimestamps.removeAll()
+            self.globalMessageTimestamps.removeAll()
+        }
+    }
+}

bitchat/Noise/NoiseSecurityConsiderations.swift

@@ -1,227 +0,0 @@
-//
-// NoiseSecurityConsiderations.swift
-// bitchat
-//
-// This is free and unencumbered software released into the public domain.
-// For more information, see <https://unlicense.org>
-//
-
-import Foundation
-import CryptoKit
-
-// MARK: - Security Constants
-
-enum NoiseSecurityConstants {
-    // Maximum message size to prevent memory exhaustion
-    static let maxMessageSize = 65535 // 64KB as per Noise spec
-    
-    // Maximum handshake message size
-    static let maxHandshakeMessageSize = 2048 // 2KB to accommodate XX pattern
-    
-    // Session timeout - sessions older than this should be renegotiated
-    static let sessionTimeout: TimeInterval = 86400 // 24 hours
-    
-    // Maximum number of messages before rekey (2^64 - 1 is the nonce limit)
-    static let maxMessagesPerSession: UInt64 = 1_000_000_000 // 1 billion messages
-    
-    // Handshake timeout - abandon incomplete handshakes
-    static let handshakeTimeout: TimeInterval = 60 // 1 minute
-    
-    // Maximum concurrent sessions per peer
-    static let maxSessionsPerPeer = 3
-    
-    // Rate limiting
-    static let maxHandshakesPerMinute = 10
-    static let maxMessagesPerSecond = 100
-    
-    // Global rate limiting (across all peers)
-    static let maxGlobalHandshakesPerMinute = 30
-    static let maxGlobalMessagesPerSecond = 500
-}
-
-// MARK: - Security Validations
-
-struct NoiseSecurityValidator {
-    
-    /// Validate message size
-    static func validateMessageSize(_ data: Data) -> Bool {
-        return data.count <= NoiseSecurityConstants.maxMessageSize
-    }
-    
-    /// Validate handshake message size
-    static func validateHandshakeMessageSize(_ data: Data) -> Bool {
-        return data.count <= NoiseSecurityConstants.maxHandshakeMessageSize
-    }
-    
-    /// Validate peer ID format
-    static func validatePeerID(_ peerID: String) -> Bool {
-        // Peer ID should be reasonable length and contain valid characters
-        let validCharset = CharacterSet.alphanumerics.union(CharacterSet(charactersIn: "-_"))
-        return peerID.count > 0 && 
-               peerID.count <= 64 && 
-               peerID.rangeOfCharacter(from: validCharset.inverted) == nil
-    }
-}
-
-// MARK: - Enhanced Noise Session with Security
-
-class SecureNoiseSession: NoiseSession {
-    private(set) var messageCount: UInt64 = 0
-    private let sessionStartTime = Date()
-    private(set) var lastActivityTime = Date()
-    
-    override func encrypt(_ plaintext: Data) throws -> Data {
-        // Check session age
-        if Date().timeIntervalSince(sessionStartTime) > NoiseSecurityConstants.sessionTimeout {
-            throw NoiseSecurityError.sessionExpired
-        }
-        
-        // Check message count
-        if messageCount >= NoiseSecurityConstants.maxMessagesPerSession {
-            throw NoiseSecurityError.sessionExhausted
-        }
-        
-        // Validate message size
-        guard NoiseSecurityValidator.validateMessageSize(plaintext) else {
-            throw NoiseSecurityError.messageTooLarge
-        }
-        
-        let encrypted = try super.encrypt(plaintext)
-        messageCount += 1
-        lastActivityTime = Date()
-        
-        return encrypted
-    }
-    
-    override func decrypt(_ ciphertext: Data) throws -> Data {
-        // Check session age
-        if Date().timeIntervalSince(sessionStartTime) > NoiseSecurityConstants.sessionTimeout {
-            throw NoiseSecurityError.sessionExpired
-        }
-        
-        // Validate message size
-        guard NoiseSecurityValidator.validateMessageSize(ciphertext) else {
-            throw NoiseSecurityError.messageTooLarge
-        }
-        
-        let decrypted = try super.decrypt(ciphertext)
-        lastActivityTime = Date()
-        
-        return decrypted
-    }
-    
-    func needsRenegotiation() -> Bool {
-        // Check if we've used more than 90% of message limit
-        let messageThreshold = UInt64(Double(NoiseSecurityConstants.maxMessagesPerSession) * 0.9)
-        if messageCount >= messageThreshold {
-            return true
-        }
-        
-        // Check if last activity was more than 30 minutes ago
-        if Date().timeIntervalSince(lastActivityTime) > NoiseSecurityConstants.sessionTimeout {
-            return true
-        }
-        
-        return false
-    }
-    
-    // MARK: - Testing Support
-    #if DEBUG
-    func setLastActivityTimeForTesting(_ date: Date) {
-        lastActivityTime = date
-    }
-    
-    func setMessageCountForTesting(_ count: UInt64) {
-        messageCount = count
-    }
-    #endif
-}
-
-// MARK: - Rate Limiter
-
-class NoiseRateLimiter {
-    private var handshakeTimestamps: [String: [Date]] = [:] // peerID -> timestamps
-    private var messageTimestamps: [String: [Date]] = [:] // peerID -> timestamps
-    
-    // Global rate limiting
-    private var globalHandshakeTimestamps: [Date] = []
-    private var globalMessageTimestamps: [Date] = []
-    
-    private let queue = DispatchQueue(label: "chat.bitchat.noise.ratelimit", attributes: .concurrent)
-    
-    func allowHandshake(from peerID: String) -> Bool {
-        return queue.sync(flags: .barrier) {
-            let now = Date()
-            let oneMinuteAgo = now.addingTimeInterval(-60)
-            
-            // Check global rate limit first
-            globalHandshakeTimestamps = globalHandshakeTimestamps.filter { $0 > oneMinuteAgo }
-            if globalHandshakeTimestamps.count >= NoiseSecurityConstants.maxGlobalHandshakesPerMinute {
-                SecureLogger.log("Global handshake rate limit exceeded: \(globalHandshakeTimestamps.count)/\(NoiseSecurityConstants.maxGlobalHandshakesPerMinute) per minute", category: SecureLogger.security, level: .warning)
-                return false
-            }
-            
-            // Check per-peer rate limit
-            var timestamps = handshakeTimestamps[peerID] ?? []
-            timestamps = timestamps.filter { $0 > oneMinuteAgo }
-            
-            if timestamps.count >= NoiseSecurityConstants.maxHandshakesPerMinute {
-                SecureLogger.log("Per-peer handshake rate limit exceeded for \(peerID): \(timestamps.count)/\(NoiseSecurityConstants.maxHandshakesPerMinute) per minute", category: SecureLogger.security, level: .warning)
-                return false
-            }
-            
-            // Record new handshake
-            timestamps.append(now)
-            handshakeTimestamps[peerID] = timestamps
-            globalHandshakeTimestamps.append(now)
-            return true
-        }
-    }
-    
-    func allowMessage(from peerID: String) -> Bool {
-        return queue.sync(flags: .barrier) {
-            let now = Date()
-            let oneSecondAgo = now.addingTimeInterval(-1)
-            
-            // Check global rate limit first
-            globalMessageTimestamps = globalMessageTimestamps.filter { $0 > oneSecondAgo }
-            if globalMessageTimestamps.count >= NoiseSecurityConstants.maxGlobalMessagesPerSecond {
-                SecureLogger.log("Global message rate limit exceeded: \(globalMessageTimestamps.count)/\(NoiseSecurityConstants.maxGlobalMessagesPerSecond) per second", category: SecureLogger.security, level: .warning)
-                return false
-            }
-            
-            // Check per-peer rate limit
-            var timestamps = messageTimestamps[peerID] ?? []
-            timestamps = timestamps.filter { $0 > oneSecondAgo }
-            
-            if timestamps.count >= NoiseSecurityConstants.maxMessagesPerSecond {
-                SecureLogger.log("Per-peer message rate limit exceeded for \(peerID): \(timestamps.count)/\(NoiseSecurityConstants.maxMessagesPerSecond) per second", category: SecureLogger.security, level: .warning)
-                return false
-            }
-            
-            // Record new message
-            timestamps.append(now)
-            messageTimestamps[peerID] = timestamps
-            globalMessageTimestamps.append(now)
-            return true
-        }
-    }
-    
-    func reset(for peerID: String) {
-        queue.async(flags: .barrier) {
-            self.handshakeTimestamps.removeValue(forKey: peerID)
-            self.messageTimestamps.removeValue(forKey: peerID)
-        }
-    }
-}
-
-// MARK: - Security Errors
-
-enum NoiseSecurityError: Error {
-    case sessionExpired
-    case sessionExhausted
-    case messageTooLarge
-    case invalidPeerID
-    case rateLimitExceeded
-    case handshakeTimeout
-}

bitchat/Noise/NoiseSecurityConstants.swift

@@ -0,0 +1,37 @@
+//
+// NoiseSecurityConstants.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+
+enum NoiseSecurityConstants {
+    // Maximum message size to prevent memory exhaustion
+    static let maxMessageSize = 65535 // 64KB as per Noise spec
+    
+    // Maximum handshake message size
+    static let maxHandshakeMessageSize = 2048 // 2KB to accommodate XX pattern
+    
+    // Session timeout - sessions older than this should be renegotiated
+    static let sessionTimeout: TimeInterval = 86400 // 24 hours
+    
+    // Maximum number of messages before rekey (2^64 - 1 is the nonce limit)
+    static let maxMessagesPerSession: UInt64 = 1_000_000_000 // 1 billion messages
+    
+    // Handshake timeout - abandon incomplete handshakes
+    static let handshakeTimeout: TimeInterval = 60 // 1 minute
+    
+    // Maximum concurrent sessions per peer
+    static let maxSessionsPerPeer = 3
+    
+    // Rate limiting
+    static let maxHandshakesPerMinute = 10
+    static let maxMessagesPerSecond = 100
+    
+    // Global rate limiting (across all peers)
+    static let maxGlobalHandshakesPerMinute = 30
+    static let maxGlobalMessagesPerSecond = 500
+}

bitchat/Noise/NoiseSecurityError.swift

@@ -0,0 +1,18 @@
+//
+// NoiseSecurityError.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+
+enum NoiseSecurityError: Error {
+    case sessionExpired
+    case sessionExhausted
+    case messageTooLarge
+    case invalidPeerID
+    case rateLimitExceeded
+    case handshakeTimeout
+}

bitchat/Noise/NoiseSecurityValidator.swift

@@ -0,0 +1,22 @@
+//
+// NoiseSecurityValidator.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+
+struct NoiseSecurityValidator {
+    
+    /// Validate message size
+    static func validateMessageSize(_ data: Data) -> Bool {
+        return data.count <= NoiseSecurityConstants.maxMessageSize
+    }
+    
+    /// Validate handshake message size
+    static func validateHandshakeMessageSize(_ data: Data) -> Bool {
+        return data.count <= NoiseSecurityConstants.maxHandshakeMessageSize
+    }
+}

bitchat/Noise/NoiseSession.swift

@@ -6,37 +6,14 @@
 // For more information, see <https://unlicense.org>
 //
 
+import BitLogger
 import Foundation
 import CryptoKit
-import os.log
-
-// MARK: - Noise Session State
-
-enum NoiseSessionState: Equatable {
-    case uninitialized
-    case handshaking
-    case established
-    case failed(Error)
-    
-    static func == (lhs: NoiseSessionState, rhs: NoiseSessionState) -> Bool {
-        switch (lhs, rhs) {
-        case (.uninitialized, .uninitialized),
-             (.handshaking, .handshaking),
-             (.established, .established):
-            return true
-        case (.failed, .failed):
-            return true // We don't compare the errors
-        default:
-            return false
-        }
-    }
-}
-
-// MARK: - Noise Session
 
 class NoiseSession {
-    let peerID: String
+    let peerID: PeerID
     let role: NoiseRole
+    private let keychain: KeychainManagerProtocol
     private var state: NoiseSessionState = .uninitialized
     private var handshakeState: NoiseHandshakeState?
     private var sendCipher: NoiseCipherState?
@@ -53,9 +30,16 @@ class NoiseSession {
     // Thread safety
     private let sessionQueue = DispatchQueue(label: "chat.bitchat.noise.session", attributes: .concurrent)
     
-    init(peerID: String, role: NoiseRole, localStaticKey: Curve25519.KeyAgreement.PrivateKey, remoteStaticKey: Curve25519.KeyAgreement.PublicKey? = nil) {
+    init(
+        peerID: PeerID,
+        role: NoiseRole,
+        keychain: KeychainManagerProtocol,
+        localStaticKey: Curve25519.KeyAgreement.PrivateKey,
+        remoteStaticKey: Curve25519.KeyAgreement.PublicKey? = nil
+    ) {
         self.peerID = peerID
         self.role = role
+        self.keychain = keychain
         self.localStaticKey = localStaticKey
         self.remoteStaticPublicKey = remoteStaticKey
     }
@@ -72,6 +56,7 @@ class NoiseSession {
             handshakeState = NoiseHandshakeState(
                 role: role,
                 pattern: .XX,
+                keychain: keychain,
                 localStaticKey: localStaticKey,
                 remoteStaticKey: nil
             )
@@ -92,18 +77,19 @@ class NoiseSession {
     
     func processHandshakeMessage(_ message: Data) throws -> Data? {
         return try sessionQueue.sync(flags: .barrier) {
-            SecureLogger.log("NoiseSession[\(peerID)]: Processing handshake message, current state: \(state), role: \(role)", category: SecureLogger.noise, level: .info)
+            SecureLogger.debug("NoiseSession[\(peerID)]: Processing handshake message, current state: \(state), role: \(role)")
             
             // Initialize handshake state if needed (for responders)
             if state == .uninitialized && role == .responder {
                 handshakeState = NoiseHandshakeState(
                     role: role,
                     pattern: .XX,
+                    keychain: keychain,
                     localStaticKey: localStaticKey,
                     remoteStaticKey: nil
                 )
                 state = .handshaking
-                SecureLogger.log("NoiseSession[\(peerID)]: Initialized handshake state for responder", category: SecureLogger.noise, level: .info)
+                SecureLogger.debug("NoiseSession[\(peerID)]: Initialized handshake state for responder")
             }
             
             guard case .handshaking = state, let handshake = handshakeState else {
@@ -112,7 +98,7 @@ class NoiseSession {
             
             // Process incoming message
             _ = try handshake.readMessage(message)
-            SecureLogger.log("NoiseSession[\(peerID)]: Read handshake message, checking if complete", category: SecureLogger.noise, level: .info)
+            SecureLogger.debug("NoiseSession[\(peerID)]: Read handshake message, checking if complete")
             
             // Check if handshake is complete
             if handshake.isHandshakeComplete() {
@@ -130,15 +116,15 @@ class NoiseSession {
                 state = .established
                 handshakeState = nil // Clear handshake state
                 
-                SecureLogger.log("NoiseSession[\(peerID)]: Handshake complete (no response needed), transitioning to established", category: SecureLogger.noise, level: .info)
-                SecureLogger.logSecurityEvent(.handshakeCompleted(peerID: peerID))
+                SecureLogger.debug("NoiseSession[\(peerID)]: Handshake complete (no response needed), transitioning to established")
+                SecureLogger.info(.handshakeCompleted(peerID: peerID.id))
                 
                 return nil
             } else {
                 // Generate response
                 let response = try handshake.writeMessage()
                 sentHandshakeMessages.append(response)
-                SecureLogger.log("NoiseSession[\(peerID)]: Generated handshake response of size \(response.count)", category: SecureLogger.noise, level: .info)
+                SecureLogger.debug("NoiseSession[\(peerID)]: Generated handshake response of size \(response.count)")
                 
                 // Check if handshake is complete after writing
                 if handshake.isHandshakeComplete() {
@@ -156,8 +142,8 @@ class NoiseSession {
                     state = .established
                     handshakeState = nil // Clear handshake state
                     
-                    SecureLogger.log("NoiseSession[\(peerID)]: Handshake complete after writing response, transitioning to established", category: SecureLogger.noise, level: .info)
-                    SecureLogger.logSecurityEvent(.handshakeCompleted(peerID: peerID))
+                    SecureLogger.debug("NoiseSession[\(peerID)]: Handshake complete after writing response, transitioning to established")
+                    SecureLogger.info(.handshakeCompleted(peerID: peerID.id))
                 }
                 
                 return response
@@ -210,262 +196,34 @@ class NoiseSession {
         }
     }
     
-    func getHandshakeHash() -> Data? {
-        return sessionQueue.sync {
-            return handshakeHash
-        }
-    }
-    
     func reset() {
         sessionQueue.sync(flags: .barrier) {
             let wasEstablished = state == .established
             state = .uninitialized
             handshakeState = nil
+            
+            // Clear sensitive cipher states
+            sendCipher?.clearSensitiveData()
+            receiveCipher?.clearSensitiveData()
             sendCipher = nil
             receiveCipher = nil
+            
+            // Clear sent handshake messages
+            for i in 0..<sentHandshakeMessages.count {
+                var message = sentHandshakeMessages[i]
+                keychain.secureClear(&message)
+            }
             sentHandshakeMessages.removeAll()
+            
+            // Clear handshake hash
+            if var hash = handshakeHash {
+                keychain.secureClear(&hash)
+            }
             handshakeHash = nil
             
             if wasEstablished {
-                SecureLogger.logSecurityEvent(.sessionExpired(peerID: peerID))
+                SecureLogger.info(.sessionExpired(peerID: peerID.id))
             }
         }
     }
 }
-
-// MARK: - Session Manager
-
-class NoiseSessionManager {
-    private var sessions: [String: NoiseSession] = [:]
-    private let localStaticKey: Curve25519.KeyAgreement.PrivateKey
-    private let managerQueue = DispatchQueue(label: "chat.bitchat.noise.manager", attributes: .concurrent)
-    
-    // Callbacks
-    var onSessionEstablished: ((String, Curve25519.KeyAgreement.PublicKey) -> Void)?
-    var onSessionFailed: ((String, Error) -> Void)?
-    
-    init(localStaticKey: Curve25519.KeyAgreement.PrivateKey) {
-        self.localStaticKey = localStaticKey
-    }
-    
-    // MARK: - Session Management
-    
-    func createSession(for peerID: String, role: NoiseRole) -> NoiseSession {
-        return managerQueue.sync(flags: .barrier) {
-            let session = SecureNoiseSession(
-                peerID: peerID,
-                role: role,
-                localStaticKey: localStaticKey
-            )
-            sessions[peerID] = session
-            return session
-        }
-    }
-    
-    func getSession(for peerID: String) -> NoiseSession? {
-        return managerQueue.sync {
-            return sessions[peerID]
-        }
-    }
-    
-    func removeSession(for peerID: String) {
-        managerQueue.sync(flags: .barrier) {
-            if let session = sessions[peerID], session.isEstablished() {
-                SecureLogger.logSecurityEvent(.sessionExpired(peerID: peerID))
-            }
-            _ = sessions.removeValue(forKey: peerID)
-        }
-    }
-    
-    func migrateSession(from oldPeerID: String, to newPeerID: String) {
-        managerQueue.sync(flags: .barrier) {
-            // Check if we have a session for the old peer ID
-            if let session = sessions[oldPeerID] {
-                // Move the session to the new peer ID
-                sessions[newPeerID] = session
-                _ = sessions.removeValue(forKey: oldPeerID)
-                
-                SecureLogger.log("Migrated Noise session from \(oldPeerID) to \(newPeerID)", category: SecureLogger.noise, level: .info)
-            }
-        }
-    }
-    
-    func getEstablishedSessions() -> [String: NoiseSession] {
-        return managerQueue.sync {
-            return sessions.filter { $0.value.isEstablished() }
-        }
-    }
-    
-    // MARK: - Handshake Helpers
-    
-    func initiateHandshake(with peerID: String) throws -> Data {
-        return try managerQueue.sync(flags: .barrier) {
-            // Check if we already have an established session
-            if let existingSession = sessions[peerID], existingSession.isEstablished() {
-                // Session already established, don't recreate
-                throw NoiseSessionError.alreadyEstablished
-            }
-            
-            // Remove any existing non-established session
-            if let existingSession = sessions[peerID], !existingSession.isEstablished() {
-                _ = sessions.removeValue(forKey: peerID)
-            }
-            
-            // Create new initiator session
-            let session = SecureNoiseSession(
-                peerID: peerID,
-                role: .initiator,
-                localStaticKey: localStaticKey
-            )
-            sessions[peerID] = session
-            
-            do {
-                let handshakeData = try session.startHandshake()
-                return handshakeData
-            } catch {
-                // Clean up failed session
-                _ = sessions.removeValue(forKey: peerID)
-                SecureLogger.logSecurityEvent(.handshakeFailed(peerID: peerID, error: error.localizedDescription), level: .error)
-                throw error
-            }
-        }
-    }
-    
-    func handleIncomingHandshake(from peerID: String, message: Data) throws -> Data? {
-        // Process everything within the synchronized block to prevent race conditions
-        return try managerQueue.sync(flags: .barrier) {
-            var shouldCreateNew = false
-            var existingSession: NoiseSession? = nil
-            
-            if let existing = sessions[peerID] {
-                // If we have an established session, the peer must have cleared their session
-                // for a good reason (e.g., decryption failure, restart, etc.)
-                // We should accept the new handshake to re-establish encryption
-                if existing.isEstablished() {
-                    SecureLogger.log("Accepting handshake from \(peerID) despite existing session - peer likely cleared their session", 
-                                   category: SecureLogger.session, level: .info)
-                    _ = sessions.removeValue(forKey: peerID)
-                    shouldCreateNew = true
-                } else {
-                    // If we're in the middle of a handshake and receive a new initiation,
-                    // reset and start fresh (the other side may have restarted)
-                    if existing.getState() == .handshaking && message.count == 32 {
-                        _ = sessions.removeValue(forKey: peerID)
-                        shouldCreateNew = true
-                    } else {
-                        existingSession = existing
-                    }
-                }
-            } else {
-                shouldCreateNew = true
-            }
-            
-            // Get or create session
-            let session: NoiseSession
-            if shouldCreateNew {
-                let newSession = SecureNoiseSession(
-                    peerID: peerID,
-                    role: .responder,
-                    localStaticKey: localStaticKey
-                )
-                sessions[peerID] = newSession
-                session = newSession
-            } else {
-                session = existingSession!
-            }
-            
-            // Process the handshake message within the synchronized block
-            do {
-                let response = try session.processHandshakeMessage(message)
-                
-                // Check if session is established after processing
-                if session.isEstablished() {
-                    if let remoteKey = session.getRemoteStaticPublicKey() {
-                        // Schedule callback outside the synchronized block to prevent deadlock
-                        DispatchQueue.global().async { [weak self] in
-                            self?.onSessionEstablished?(peerID, remoteKey)
-                        }
-                    }
-                }
-                
-                return response
-            } catch {
-                // Reset the session on handshake failure so next attempt can start fresh
-                _ = sessions.removeValue(forKey: peerID)
-                
-                // Schedule callback outside the synchronized block to prevent deadlock
-                DispatchQueue.global().async { [weak self] in
-                    self?.onSessionFailed?(peerID, error)
-                }
-                
-                SecureLogger.logSecurityEvent(.handshakeFailed(peerID: peerID, error: error.localizedDescription), level: .error)
-                throw error
-            }
-        }
-    }
-    
-    // MARK: - Encryption/Decryption
-    
-    func encrypt(_ plaintext: Data, for peerID: String) throws -> Data {
-        guard let session = getSession(for: peerID) else {
-            throw NoiseSessionError.sessionNotFound
-        }
-        
-        return try session.encrypt(plaintext)
-    }
-    
-    func decrypt(_ ciphertext: Data, from peerID: String) throws -> Data {
-        guard let session = getSession(for: peerID) else {
-            throw NoiseSessionError.sessionNotFound
-        }
-        
-        return try session.decrypt(ciphertext)
-    }
-    
-    // MARK: - Key Management
-    
-    func getRemoteStaticKey(for peerID: String) -> Curve25519.KeyAgreement.PublicKey? {
-        return getSession(for: peerID)?.getRemoteStaticPublicKey()
-    }
-    
-    func getHandshakeHash(for peerID: String) -> Data? {
-        return getSession(for: peerID)?.getHandshakeHash()
-    }
-    
-    // MARK: - Session Rekeying
-    
-    func getSessionsNeedingRekey() -> [(peerID: String, needsRekey: Bool)] {
-        return managerQueue.sync {
-            var needingRekey: [(peerID: String, needsRekey: Bool)] = []
-            
-            for (peerID, session) in sessions {
-                if let secureSession = session as? SecureNoiseSession,
-                   secureSession.isEstablished(),
-                   secureSession.needsRenegotiation() {
-                    needingRekey.append((peerID: peerID, needsRekey: true))
-                }
-            }
-            
-            return needingRekey
-        }
-    }
-    
-    func initiateRekey(for peerID: String) throws {
-        // Remove old session
-        removeSession(for: peerID)
-        
-        // Initiate new handshake
-        _ = try initiateHandshake(with: peerID)
-        
-    }
-}
-
-// MARK: - Errors
-
-enum NoiseSessionError: Error {
-    case invalidState
-    case notEstablished
-    case sessionNotFound
-    case handshakeFailed(Error)
-    case alreadyEstablished
-}

bitchat/Noise/NoiseSessionError.swift

@@ -0,0 +1,14 @@
+//
+// NoiseSessionError.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+enum NoiseSessionError: Error, Equatable {
+    case invalidState
+    case notEstablished
+    case sessionNotFound
+    case alreadyEstablished
+}

bitchat/Noise/NoiseSessionManager.swift

@@ -0,0 +1,211 @@
+//
+// NoiseSessionManager.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import BitLogger
+import CryptoKit
+import Foundation
+
+final class NoiseSessionManager {
+    private var sessions: [PeerID: NoiseSession] = [:]
+    private let localStaticKey: Curve25519.KeyAgreement.PrivateKey
+    private let keychain: KeychainManagerProtocol
+    private let managerQueue = DispatchQueue(label: "chat.bitchat.noise.manager", attributes: .concurrent)
+    
+    // Callbacks
+    var onSessionEstablished: ((PeerID, Curve25519.KeyAgreement.PublicKey) -> Void)?
+    var onSessionFailed: ((PeerID, Error) -> Void)?
+    
+    init(localStaticKey: Curve25519.KeyAgreement.PrivateKey, keychain: KeychainManagerProtocol) {
+        self.localStaticKey = localStaticKey
+        self.keychain = keychain
+    }
+    
+    // MARK: - Session Management
+    
+    func getSession(for peerID: PeerID) -> NoiseSession? {
+        return managerQueue.sync {
+            return sessions[peerID]
+        }
+    }
+    
+    func removeSession(for peerID: PeerID) {
+        managerQueue.sync(flags: .barrier) {
+            if let session = sessions.removeValue(forKey: peerID) {
+                session.reset() // Clear sensitive data before removing
+            }
+        }
+    }
+
+    func removeAllSessions() {
+        managerQueue.sync(flags: .barrier) {
+            for (_, session) in sessions {
+                session.reset()
+            }
+            sessions.removeAll()
+        }
+    }
+    
+    // MARK: - Handshake Helpers
+    
+    func initiateHandshake(with peerID: PeerID) throws -> Data {
+        return try managerQueue.sync(flags: .barrier) {
+            // Check if we already have an established session
+            if let existingSession = sessions[peerID], existingSession.isEstablished() {
+                // Session already established, don't recreate
+                throw NoiseSessionError.alreadyEstablished
+            }
+            
+            // Remove any existing non-established session
+            if let existingSession = sessions[peerID], !existingSession.isEstablished() {
+                _ = sessions.removeValue(forKey: peerID)
+            }
+            
+            // Create new initiator session
+            let session = SecureNoiseSession(
+                peerID: peerID,
+                role: .initiator,
+                keychain: keychain,
+                localStaticKey: localStaticKey
+            )
+            sessions[peerID] = session
+            
+            do {
+                let handshakeData = try session.startHandshake()
+                return handshakeData
+            } catch {
+                // Clean up failed session
+                _ = sessions.removeValue(forKey: peerID)
+                SecureLogger.error(.handshakeFailed(peerID: peerID.id, error: error.localizedDescription))
+                throw error
+            }
+        }
+    }
+    
+    func handleIncomingHandshake(from peerID: PeerID, message: Data) throws -> Data? {
+        // Process everything within the synchronized block to prevent race conditions
+        return try managerQueue.sync(flags: .barrier) {
+            var shouldCreateNew = false
+            var existingSession: NoiseSession? = nil
+            
+            if let existing = sessions[peerID] {
+                // If we have an established session, the peer must have cleared their session
+                // for a good reason (e.g., decryption failure, restart, etc.)
+                // We should accept the new handshake to re-establish encryption
+                if existing.isEstablished() {
+                    SecureLogger.info("Accepting handshake from \(peerID) despite existing session - peer likely cleared their session", category: .session)
+                    _ = sessions.removeValue(forKey: peerID)
+                    shouldCreateNew = true
+                } else {
+                    // If we're in the middle of a handshake and receive a new initiation,
+                    // reset and start fresh (the other side may have restarted)
+                    if existing.getState() == .handshaking && message.count == 32 {
+                        _ = sessions.removeValue(forKey: peerID)
+                        shouldCreateNew = true
+                    } else {
+                        existingSession = existing
+                    }
+                }
+            } else {
+                shouldCreateNew = true
+            }
+            
+            // Get or create session
+            let session: NoiseSession
+            if shouldCreateNew {
+                let newSession = SecureNoiseSession(
+                    peerID: peerID,
+                    role: .responder,
+                    keychain: keychain,
+                    localStaticKey: localStaticKey
+                )
+                sessions[peerID] = newSession
+                session = newSession
+            } else {
+                session = existingSession!
+            }
+            
+            // Process the handshake message within the synchronized block
+            do {
+                let response = try session.processHandshakeMessage(message)
+                
+                // Check if session is established after processing
+                if session.isEstablished() {
+                    if let remoteKey = session.getRemoteStaticPublicKey() {
+                        // Schedule callback outside the synchronized block to prevent deadlock
+                        DispatchQueue.global().async { [weak self] in
+                            self?.onSessionEstablished?(peerID, remoteKey)
+                        }
+                    }
+                }
+                
+                return response
+            } catch {
+                // Reset the session on handshake failure so next attempt can start fresh
+                _ = sessions.removeValue(forKey: peerID)
+                
+                // Schedule callback outside the synchronized block to prevent deadlock
+                DispatchQueue.global().async { [weak self] in
+                    self?.onSessionFailed?(peerID, error)
+                }
+                
+                SecureLogger.error(.handshakeFailed(peerID: peerID.id, error: error.localizedDescription))
+                throw error
+            }
+        }
+    }
+    
+    // MARK: - Encryption/Decryption
+    
+    func encrypt(_ plaintext: Data, for peerID: PeerID) throws -> Data {
+        guard let session = getSession(for: peerID) else {
+            throw NoiseSessionError.sessionNotFound
+        }
+        
+        return try session.encrypt(plaintext)
+    }
+    
+    func decrypt(_ ciphertext: Data, from peerID: PeerID) throws -> Data {
+        guard let session = getSession(for: peerID) else {
+            throw NoiseSessionError.sessionNotFound
+        }
+        
+        return try session.decrypt(ciphertext)
+    }
+    
+    // MARK: - Key Management
+    
+    func getRemoteStaticKey(for peerID: PeerID) -> Curve25519.KeyAgreement.PublicKey? {
+        return getSession(for: peerID)?.getRemoteStaticPublicKey()
+    }
+    
+    // MARK: - Session Rekeying
+    
+    func getSessionsNeedingRekey() -> [(peerID: PeerID, needsRekey: Bool)] {
+        return managerQueue.sync {
+            var needingRekey: [(peerID: PeerID, needsRekey: Bool)] = []
+            
+            for (peerID, session) in sessions {
+                if let secureSession = session as? SecureNoiseSession,
+                   secureSession.isEstablished(),
+                   secureSession.needsRenegotiation() {
+                    needingRekey.append((peerID: peerID, needsRekey: true))
+                }
+            }
+            
+            return needingRekey
+        }
+    }
+    
+    func initiateRekey(for peerID: PeerID) throws {
+        // Remove old session
+        removeSession(for: peerID)
+        
+        // Initiate new handshake
+        _ = try initiateHandshake(with: peerID)
+    }
+}

bitchat/Noise/NoiseSessionState.swift

@@ -0,0 +1,13 @@
+//
+// NoiseSessionState.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+enum NoiseSessionState: Equatable {
+    case uninitialized
+    case handshaking
+    case established
+}

bitchat/Noise/SecureNoiseSession.swift

@@ -0,0 +1,81 @@
+//
+// SecureNoiseSession.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+
+final class SecureNoiseSession: NoiseSession {
+    private(set) var messageCount: UInt64 = 0
+    private let sessionStartTime = Date()
+    private(set) var lastActivityTime = Date()
+    
+    override func encrypt(_ plaintext: Data) throws -> Data {
+        // Check session age
+        if Date().timeIntervalSince(sessionStartTime) > NoiseSecurityConstants.sessionTimeout {
+            throw NoiseSecurityError.sessionExpired
+        }
+        
+        // Check message count
+        if messageCount >= NoiseSecurityConstants.maxMessagesPerSession {
+            throw NoiseSecurityError.sessionExhausted
+        }
+        
+        // Validate message size
+        guard NoiseSecurityValidator.validateMessageSize(plaintext) else {
+            throw NoiseSecurityError.messageTooLarge
+        }
+        
+        let encrypted = try super.encrypt(plaintext)
+        messageCount += 1
+        lastActivityTime = Date()
+        
+        return encrypted
+    }
+    
+    override func decrypt(_ ciphertext: Data) throws -> Data {
+        // Check session age
+        if Date().timeIntervalSince(sessionStartTime) > NoiseSecurityConstants.sessionTimeout {
+            throw NoiseSecurityError.sessionExpired
+        }
+        
+        // Validate message size
+        guard NoiseSecurityValidator.validateMessageSize(ciphertext) else {
+            throw NoiseSecurityError.messageTooLarge
+        }
+        
+        let decrypted = try super.decrypt(ciphertext)
+        lastActivityTime = Date()
+        
+        return decrypted
+    }
+    
+    func needsRenegotiation() -> Bool {
+        // Check if we've used more than 90% of message limit
+        let messageThreshold = UInt64(Double(NoiseSecurityConstants.maxMessagesPerSession) * 0.9)
+        if messageCount >= messageThreshold {
+            return true
+        }
+        
+        // Check if last activity was more than 30 minutes ago
+        if Date().timeIntervalSince(lastActivityTime) > NoiseSecurityConstants.sessionTimeout {
+            return true
+        }
+        
+        return false
+    }
+    
+    // MARK: - Testing Support
+    #if DEBUG
+    func setLastActivityTimeForTesting(_ date: Date) {
+        lastActivityTime = date
+    }
+    
+    func setMessageCountForTesting(_ count: UInt64) {
+        messageCount = count
+    }
+    #endif
+}

bitchat/Nostr/Bech32.swift

@@ -0,0 +1,135 @@
+import Foundation
+
+/// Bech32 encoding for Nostr (minimal implementation)
+enum Bech32 {
+    private static let charset = "qpzry9x8gf2tvdw0s3jn54khce6mua7l"
+    private static let generator = [0x3b6a57b2, 0x26508e6d, 0x1ea119fa, 0x3d4233dd, 0x2a1462b3]
+    
+    static func encode(hrp: String, data: Data) throws -> String {
+        let values = convertBits(from: 8, to: 5, pad: true, data: Array(data))
+        let checksum = createChecksum(hrp: hrp, values: values)
+        let combined = values + checksum
+        
+        return hrp + "1" + combined.map { 
+            let index = charset.index(charset.startIndex, offsetBy: Int($0))
+            return String(charset[index])
+        }.joined()
+    }
+    
+    static func decode(_ bech32String: String) throws -> (hrp: String, data: Data) {
+        // Find the last occurrence of '1'
+        guard let separatorIndex = bech32String.lastIndex(of: "1") else {
+            throw Bech32Error.invalidFormat
+        }
+        
+        let hrp = String(bech32String[..<separatorIndex])
+        
+        // Validate HRP contains only ASCII characters
+        for char in hrp {
+            guard char.asciiValue != nil else {
+                throw Bech32Error.invalidCharacter
+            }
+        }
+        
+        let dataString = String(bech32String[bech32String.index(after: separatorIndex)...])
+        
+        // Convert characters to values
+        var values = [UInt8]()
+        for char in dataString {
+            guard let index = charset.firstIndex(of: char) else {
+                throw Bech32Error.invalidCharacter
+            }
+            values.append(UInt8(charset.distance(from: charset.startIndex, to: index)))
+        }
+        
+        // Verify checksum
+        guard values.count >= 6 else {
+            throw Bech32Error.invalidChecksum
+        }
+        
+        let payloadValues = Array(values.dropLast(6))
+        let checksum = Array(values.suffix(6))
+        let expectedChecksum = createChecksum(hrp: hrp, values: payloadValues)
+        
+        guard checksum == expectedChecksum else {
+            throw Bech32Error.invalidChecksum
+        }
+        
+        // Convert back to bytes
+        let bytes = convertBits(from: 5, to: 8, pad: false, data: payloadValues)
+        return (hrp: hrp, data: Data(bytes))
+    }
+    
+    enum Bech32Error: Error {
+        case invalidFormat
+        case invalidCharacter
+        case invalidChecksum
+    }
+    
+    private static func convertBits(from: Int, to: Int, pad: Bool, data: [UInt8]) -> [UInt8] {
+        var acc = 0
+        var bits = 0
+        var result = [UInt8]()
+        let maxv = (1 << to) - 1
+        
+        for value in data {
+            acc = (acc << from) | Int(value)
+            bits += from
+            
+            while bits >= to {
+                bits -= to
+                result.append(UInt8((acc >> bits) & maxv))
+            }
+        }
+        
+        if pad && bits > 0 {
+            result.append(UInt8((acc << (to - bits)) & maxv))
+        }
+        
+        return result
+    }
+    
+    private static func createChecksum(hrp: String, values: [UInt8]) -> [UInt8] {
+        let checksumValues = hrpExpand(hrp) + values + [0, 0, 0, 0, 0, 0]
+        let polymod = polymod(checksumValues) ^ 1
+        var checksum = [UInt8]()
+        
+        for i in 0..<6 {
+            checksum.append(UInt8((polymod >> (5 * (5 - i))) & 31))
+        }
+        
+        return checksum
+    }
+    
+    private static func hrpExpand(_ hrp: String) -> [UInt8] {
+        var result = [UInt8]()
+        for c in hrp {
+            guard let asciiValue = c.asciiValue else {
+                return [] // Return empty array for invalid input
+            }
+            result.append(UInt8(asciiValue >> 5))
+        }
+        result.append(0)
+        for c in hrp {
+            guard let asciiValue = c.asciiValue else {
+                return [] // Return empty array for invalid input
+            }
+            result.append(UInt8(asciiValue & 31))
+        }
+        return result
+    }
+    
+    private static func polymod(_ values: [UInt8]) -> Int {
+        var chk = 1
+        for value in values {
+            let b = chk >> 25
+            chk = (chk & 0x1ffffff) << 5 ^ Int(value)
+            for i in 0..<5 {
+                if (b >> i) & 1 == 1 {
+                    chk ^= generator[i]
+                }
+            }
+        }
+        return chk
+    }
+}

bitchat/Nostr/GeoRelayDirectory.swift

@@ -0,0 +1,345 @@
+import BitLogger
+import Foundation
+import Tor
+#if os(iOS)
+import UIKit
+#elseif os(macOS)
+import AppKit
+#endif
+
+/// Directory of online Nostr relays with approximate GPS locations, used for geohash routing.
+@MainActor
+final class GeoRelayDirectory {
+    struct Entry: Hashable {
+        let host: String
+        let lat: Double
+        let lon: Double
+    }
+
+    static let shared = GeoRelayDirectory()
+
+    private(set) var entries: [Entry] = []
+    private let cacheFileName = "georelays_cache.csv"
+    private let lastFetchKey = "georelay.lastFetchAt"
+    private let remoteURL = URL(string: "https://raw.githubusercontent.com/permissionlesstech/georelays/refs/heads/main/nostr_relays.csv")!
+    private let fetchInterval: TimeInterval = TransportConfig.geoRelayFetchIntervalSeconds
+
+    private var refreshTimer: Timer?
+    private var retryTask: Task<Void, Never>?
+    private var retryAttempt: Int = 0
+    private var isFetching: Bool = false
+    private var observers: [NSObjectProtocol] = []
+
+    private init() {
+        entries = loadLocalEntries()
+        registerObservers()
+        startRefreshTimer()
+        prefetchIfNeeded()
+    }
+
+    deinit {
+        observers.forEach { NotificationCenter.default.removeObserver($0) }
+        refreshTimer?.invalidate()
+        retryTask?.cancel()
+    }
+
+    /// Returns up to `count` relay URLs (wss://) closest to the geohash center.
+    func closestRelays(toGeohash geohash: String, count: Int = 5) -> [String] {
+        let center = Geohash.decodeCenter(geohash)
+        return closestRelays(toLat: center.lat, lon: center.lon, count: count)
+    }
+
+    /// Returns up to `count` relay URLs (wss://) closest to the given coordinate.
+    func closestRelays(toLat lat: Double, lon: Double, count: Int = 5) -> [String] {
+        guard !entries.isEmpty, count > 0 else { return [] }
+
+        if entries.count <= count {
+            return entries
+                .sorted { a, b in
+                    haversineKm(lat, lon, a.lat, a.lon) < haversineKm(lat, lon, b.lat, b.lon)
+                }
+                .map { "wss://\($0.host)" }
+        }
+
+        var best: [(entry: Entry, distance: Double)] = []
+        best.reserveCapacity(count)
+
+        for entry in entries {
+            let distance = haversineKm(lat, lon, entry.lat, entry.lon)
+            if best.count < count {
+                let idx = best.firstIndex { $0.distance > distance } ?? best.count
+                best.insert((entry, distance), at: idx)
+            } else if let worstDistance = best.last?.distance, distance < worstDistance {
+                let idx = best.firstIndex { $0.distance > distance } ?? best.count
+                best.insert((entry, distance), at: idx)
+                best.removeLast()
+            }
+        }
+
+        return best.map { "wss://\($0.entry.host)" }
+    }
+
+    // MARK: - Remote Fetch
+    func prefetchIfNeeded(force: Bool = false) {
+        guard !isFetching else { return }
+
+        let now = Date()
+        let last = UserDefaults.standard.object(forKey: lastFetchKey) as? Date ?? .distantPast
+
+        if !force {
+            guard now.timeIntervalSince(last) >= fetchInterval else { return }
+        } else if last != .distantPast,
+                  now.timeIntervalSince(last) < TransportConfig.geoRelayRetryInitialSeconds {
+            // Skip forced fetches if we just refreshed moments ago.
+            return
+        }
+
+        cancelRetry()
+        fetchRemote()
+    }
+
+    private func fetchRemote() {
+        guard !isFetching else { return }
+        isFetching = true
+
+        let request = URLRequest(
+            url: remoteURL,
+            cachePolicy: .reloadIgnoringLocalCacheData,
+            timeoutInterval: 15
+        )
+
+        Task.detached { [weak self] in
+            guard let self else { return }
+
+            let ready = await TorManager.shared.awaitReady()
+            if !ready {
+                await self.handleFetchFailure(.torNotReady)
+                return
+            }
+
+            do {
+                let (data, _) = try await TorURLSession.shared.session.data(for: request)
+                guard let text = String(data: data, encoding: .utf8) else {
+                    await self.handleFetchFailure(.invalidData)
+                    return
+                }
+
+                let parsed = GeoRelayDirectory.parseCSV(text)
+                guard !parsed.isEmpty else {
+                    await self.handleFetchFailure(.invalidData)
+                    return
+                }
+
+                await self.handleFetchSuccess(entries: parsed, csv: text)
+            } catch {
+                await self.handleFetchFailure(.network(error))
+            }
+        }
+    }
+
+    private enum FetchFailure {
+        case torNotReady
+        case invalidData
+        case network(Error)
+    }
+
+    @MainActor
+    private func handleFetchSuccess(entries parsed: [Entry], csv: String) {
+        entries = parsed
+        persistCache(csv)
+        UserDefaults.standard.set(Date(), forKey: lastFetchKey)
+        SecureLogger.info("GeoRelayDirectory: refreshed \(parsed.count) relays from remote", category: .session)
+        isFetching = false
+        retryAttempt = 0
+        cancelRetry()
+    }
+
+    @MainActor
+    private func handleFetchFailure(_ reason: FetchFailure) {
+        switch reason {
+        case .torNotReady:
+            SecureLogger.warning("GeoRelayDirectory: Tor not ready; scheduling retry", category: .session)
+        case .invalidData:
+            SecureLogger.warning("GeoRelayDirectory: remote fetch returned invalid data; scheduling retry", category: .session)
+        case .network(let error):
+            SecureLogger.warning("GeoRelayDirectory: remote fetch failed with error: \(error.localizedDescription)", category: .session)
+        }
+        isFetching = false
+        scheduleRetry()
+    }
+
+    @MainActor
+    private func scheduleRetry() {
+        retryAttempt = min(retryAttempt + 1, 10)
+        let base = TransportConfig.geoRelayRetryInitialSeconds
+        let maxDelay = TransportConfig.geoRelayRetryMaxSeconds
+        let multiplier = pow(2.0, Double(max(retryAttempt - 1, 0)))
+        let calculated = base * multiplier
+        let delay = min(maxDelay, max(base, calculated))
+
+        cancelRetry()
+        retryTask = Task { [weak self] in
+            let nanoseconds = UInt64(delay * 1_000_000_000)
+            try? await Task.sleep(nanoseconds: nanoseconds)
+            await MainActor.run {
+                self?.prefetchIfNeeded(force: true)
+            }
+        }
+    }
+
+    @MainActor
+    private func cancelRetry() {
+        retryTask?.cancel()
+        retryTask = nil
+    }
+
+    private func persistCache(_ text: String) {
+        guard let url = cacheURL() else { return }
+        do {
+            try text.data(using: .utf8)?.write(to: url, options: .atomic)
+        } catch {
+            SecureLogger.warning("GeoRelayDirectory: failed to write cache: \(error)", category: .session)
+        }
+    }
+
+    // MARK: - Loading
+    private func loadLocalEntries() -> [Entry] {
+        // Prefer cached file if present
+        if let cache = cacheURL(),
+           let data = try? Data(contentsOf: cache),
+           let text = String(data: data, encoding: .utf8) {
+            let arr = Self.parseCSV(text)
+            if !arr.isEmpty { return arr }
+        }
+
+        // Try bundled resource(s)
+        let bundleCandidates = [
+            Bundle.main.url(forResource: "nostr_relays", withExtension: "csv"),
+            Bundle.main.url(forResource: "online_relays_gps", withExtension: "csv"),
+            Bundle.main.url(forResource: "online_relays_gps", withExtension: "csv", subdirectory: "relays")
+        ].compactMap { $0 }
+
+        for url in bundleCandidates {
+            if let data = try? Data(contentsOf: url),
+               let text = String(data: data, encoding: .utf8) {
+                let arr = Self.parseCSV(text)
+                if !arr.isEmpty { return arr }
+            }
+        }
+
+        // Try filesystem path (development/test)
+        if let cwd = FileManager.default.currentDirectoryPath as String?,
+           let data = try? Data(contentsOf: URL(fileURLWithPath: cwd).appendingPathComponent("relays/online_relays_gps.csv")),
+           let text = String(data: data, encoding: .utf8) {
+            return Self.parseCSV(text)
+        }
+
+        SecureLogger.warning("GeoRelayDirectory: no local CSV found; entries empty", category: .session)
+        return []
+    }
+
+    nonisolated static func parseCSV(_ text: String) -> [Entry] {
+        var result: Set<Entry> = []
+        let lines = text.split(whereSeparator: { $0.isNewline })
+        for (idx, raw) in lines.enumerated() {
+            let line = raw.trimmingCharacters(in: .whitespacesAndNewlines)
+            if line.isEmpty { continue }
+            if idx == 0 && line.lowercased().contains("relay url") { continue }
+            let parts = line.split(separator: ",").map { String($0).trimmingCharacters(in: .whitespaces) }
+            guard parts.count >= 3 else { continue }
+            var host = parts[0]
+            host = host.replacingOccurrences(of: "https://", with: "")
+            host = host.replacingOccurrences(of: "http://", with: "")
+            host = host.replacingOccurrences(of: "wss://", with: "")
+            host = host.replacingOccurrences(of: "ws://", with: "")
+            host = host.trimmingCharacters(in: CharacterSet(charactersIn: "/"))
+            guard let lat = Double(parts[1]), let lon = Double(parts[2]) else { continue }
+            result.insert(Entry(host: host, lat: lat, lon: lon))
+        }
+        return Array(result)
+    }
+
+    private func cacheURL() -> URL? {
+        do {
+            let base = try FileManager.default.url(
+                for: .applicationSupportDirectory,
+                in: .userDomainMask,
+                appropriateFor: nil,
+                create: true
+            )
+            let dir = base.appendingPathComponent("bitchat", isDirectory: true)
+            try? FileManager.default.createDirectory(at: dir, withIntermediateDirectories: true)
+            return dir.appendingPathComponent(cacheFileName)
+        } catch {
+            return nil
+        }
+    }
+
+    // MARK: - Observers & Timers
+    private func registerObservers() {
+        let center = NotificationCenter.default
+
+        let torReady = center.addObserver(
+            forName: .TorDidBecomeReady,
+            object: nil,
+            queue: .main
+        ) { [weak self] _ in
+            guard let self else { return }
+            Task { @MainActor in
+                self.prefetchIfNeeded(force: true)
+            }
+        }
+        observers.append(torReady)
+
+#if os(iOS)
+        let didBecomeActive = center.addObserver(
+            forName: UIApplication.didBecomeActiveNotification,
+            object: nil,
+            queue: .main
+        ) { [weak self] _ in
+            guard let self else { return }
+            Task { @MainActor in
+                self.prefetchIfNeeded()
+            }
+        }
+        observers.append(didBecomeActive)
+#elseif os(macOS)
+        let didBecomeActive = center.addObserver(
+            forName: NSApplication.didBecomeActiveNotification,
+            object: nil,
+            queue: .main
+        ) { [weak self] _ in
+            guard let self else { return }
+            Task { @MainActor in
+                self.prefetchIfNeeded()
+            }
+        }
+        observers.append(didBecomeActive)
+#endif
+    }
+
+    private func startRefreshTimer() {
+        refreshTimer?.invalidate()
+        let interval = TransportConfig.geoRelayRefreshCheckIntervalSeconds
+        guard interval > 0 else { return }
+
+        let timer = Timer.scheduledTimer(withTimeInterval: interval, repeats: true) { [weak self] _ in
+            guard let self else { return }
+            Task { @MainActor in
+                self.prefetchIfNeeded()
+            }
+        }
+        refreshTimer = timer
+        RunLoop.main.add(timer, forMode: .common)
+    }
+}
+
+// MARK: - Distance
+private func haversineKm(_ lat1: Double, _ lon1: Double, _ lat2: Double, _ lon2: Double) -> Double {
+    let r = 6371.0 // Earth radius in km
+    let dLat = (lat2 - lat1) * .pi / 180
+    let dLon = (lon2 - lon1) * .pi / 180
+    let a = sin(dLat/2) * sin(dLat/2) + cos(lat1 * .pi/180) * cos(lat2 * .pi/180) * sin(dLon/2) * sin(dLon/2)
+    let c = 2 * atan2(sqrt(a), sqrt(1 - a))
+    return r * c
+}

bitchat/Nostr/KeychainHelper.swift

@@ -0,0 +1,50 @@
+import Foundation
+
+protocol KeychainHelperProtocol {
+    func save(key: String, data: Data, service: String, accessible: CFString?)
+    func load(key: String, service: String) -> Data?
+    func delete(key: String, service: String)
+}
+
+/// Keychain helper for secure storage
+struct KeychainHelper: KeychainHelperProtocol {
+    func save(key: String, data: Data, service: String, accessible: CFString? = nil) {
+        var query: [String: Any] = [
+            kSecClass as String: kSecClassGenericPassword,
+            kSecAttrService as String: service,
+            kSecAttrAccount as String: key,
+            kSecValueData as String: data
+        ]
+        if let accessible = accessible {
+            query[kSecAttrAccessible as String] = accessible
+        }
+        
+        SecItemDelete(query as CFDictionary)
+        SecItemAdd(query as CFDictionary, nil)
+    }
+    
+    func load(key: String, service: String) -> Data? {
+        let query: [String: Any] = [
+            kSecClass as String: kSecClassGenericPassword,
+            kSecAttrService as String: service,
+            kSecAttrAccount as String: key,
+            kSecReturnData as String: true
+        ]
+        
+        var result: AnyObject?
+        let status = SecItemCopyMatching(query as CFDictionary, &result)
+        
+        guard status == errSecSuccess else { return nil }
+        return result as? Data
+    }
+    
+    func delete(key: String, service: String) {
+        let query: [String: Any] = [
+            kSecClass as String: kSecClassGenericPassword,
+            kSecAttrService as String: service,
+            kSecAttrAccount as String: key
+        ]
+        
+        SecItemDelete(query as CFDictionary)
+    }
+}

bitchat/Nostr/NostrEmbeddedBitChat.swift

@@ -0,0 +1,121 @@
+import Foundation
+
+// MARK: - BitChat-over-Nostr Adapter
+
+struct NostrEmbeddedBitChat {
+    /// Build a `bitchat1:` base64url-encoded BitChat packet carrying a private message for Nostr DMs.
+    static func encodePMForNostr(content: String, messageID: String, recipientPeerID: PeerID, senderPeerID: PeerID) -> String? {
+        // TLV-encode the private message
+        let pm = PrivateMessagePacket(messageID: messageID, content: content)
+        guard let tlv = pm.encode() else { return nil }
+
+        // Prefix with NoisePayloadType
+        var payload = Data([NoisePayloadType.privateMessage.rawValue])
+        payload.append(tlv)
+
+        // Determine 8-byte recipient ID to embed
+        let recipientID = normalizeRecipientPeerID(recipientPeerID)
+
+        let packet = BitchatPacket(
+            type: MessageType.noiseEncrypted.rawValue,
+            senderID: Data(hexString: senderPeerID.id) ?? Data(),
+            recipientID: Data(hexString: recipientID.id),
+            timestamp: UInt64(Date().timeIntervalSince1970 * 1000),
+            payload: payload,
+            signature: nil,
+            ttl: 7
+        )
+
+        guard let data = packet.toBinaryData() else { return nil }
+        return "bitchat1:" + base64URLEncode(data)
+    }
+
+    /// Build a `bitchat1:` base64url-encoded BitChat packet carrying a delivery/read ack for Nostr DMs.
+    static func encodeAckForNostr(type: NoisePayloadType, messageID: String, recipientPeerID: PeerID, senderPeerID: PeerID) -> String? {
+        guard type == .delivered || type == .readReceipt else { return nil }
+
+        var payload = Data([type.rawValue])
+        payload.append(Data(messageID.utf8))
+
+        let recipientID = normalizeRecipientPeerID(recipientPeerID)
+
+        let packet = BitchatPacket(
+            type: MessageType.noiseEncrypted.rawValue,
+            senderID: Data(hexString: senderPeerID.id) ?? Data(),
+            recipientID: Data(hexString: recipientID.id),
+            timestamp: UInt64(Date().timeIntervalSince1970 * 1000),
+            payload: payload,
+            signature: nil,
+            ttl: 7
+        )
+
+        guard let data = packet.toBinaryData() else { return nil }
+        return "bitchat1:" + base64URLEncode(data)
+    }
+
+    /// Build a `bitchat1:` ACK (delivered/read) without an embedded recipient peer ID (geohash DMs).
+    static func encodeAckForNostrNoRecipient(type: NoisePayloadType, messageID: String, senderPeerID: PeerID) -> String? {
+        guard type == .delivered || type == .readReceipt else { return nil }
+
+        var payload = Data([type.rawValue])
+        payload.append(Data(messageID.utf8))
+
+        let packet = BitchatPacket(
+            type: MessageType.noiseEncrypted.rawValue,
+            senderID: Data(hexString: senderPeerID.id) ?? Data(),
+            recipientID: nil,
+            timestamp: UInt64(Date().timeIntervalSince1970 * 1000),
+            payload: payload,
+            signature: nil,
+            ttl: 7
+        )
+
+        guard let data = packet.toBinaryData() else { return nil }
+        return "bitchat1:" + base64URLEncode(data)
+    }
+
+    /// Build a `bitchat1:` payload without an embedded recipient peer ID (used for geohash DMs).
+    static func encodePMForNostrNoRecipient(content: String, messageID: String, senderPeerID: PeerID) -> String? {
+        let pm = PrivateMessagePacket(messageID: messageID, content: content)
+        guard let tlv = pm.encode() else { return nil }
+
+        var payload = Data([NoisePayloadType.privateMessage.rawValue])
+        payload.append(tlv)
+
+        let packet = BitchatPacket(
+            type: MessageType.noiseEncrypted.rawValue,
+            senderID: Data(hexString: senderPeerID.id) ?? Data(),
+            recipientID: nil,
+            timestamp: UInt64(Date().timeIntervalSince1970 * 1000),
+            payload: payload,
+            signature: nil,
+            ttl: 7
+        )
+
+        guard let data = packet.toBinaryData() else { return nil }
+        return "bitchat1:" + base64URLEncode(data)
+    }
+
+    private static func normalizeRecipientPeerID(_ recipientPeerID: PeerID) -> PeerID {
+        if let maybeData = Data(hexString: recipientPeerID.id) {
+            if maybeData.count == 32 {
+                // Treat as Noise static public key; derive peerID from fingerprint
+                return PeerID(publicKey: maybeData)
+            } else if maybeData.count == 8 {
+                // Already an 8-byte peer ID
+                return recipientPeerID
+            }
+        }
+        // Fallback: return as-is (expecting 16 hex chars) – caller should pass a valid peer ID
+        return recipientPeerID
+    }
+
+    /// Base64url encode without padding
+    private static func base64URLEncode(_ data: Data) -> String {
+        let b64 = data.base64EncodedString()
+        return b64
+            .replacingOccurrences(of: "+", with: "-")
+            .replacingOccurrences(of: "/", with: "_")
+            .replacingOccurrences(of: "=", with: "")
+    }
+}

bitchat/Nostr/NostrIdentity.swift

@@ -0,0 +1,60 @@
+import Foundation
+import P256K
+
+/// Manages Nostr identity (secp256k1 keypair) for NIP-17 private messaging
+struct NostrIdentity: Codable {
+    let privateKey: Data
+    let publicKey: Data
+    let npub: String // Bech32-encoded public key
+    let createdAt: Date
+    
+    /// Memberwise initializer
+    init(privateKey: Data, publicKey: Data, npub: String, createdAt: Date) {
+        self.privateKey = privateKey
+        self.publicKey = publicKey
+        self.npub = npub
+        self.createdAt = createdAt
+    }
+    
+    /// Generate a new Nostr identity
+    static func generate() throws -> NostrIdentity {
+        // Generate Schnorr key for Nostr
+        let schnorrKey = try P256K.Schnorr.PrivateKey()
+        let xOnlyPubkey = Data(schnorrKey.xonly.bytes)
+        let npub = try Bech32.encode(hrp: "npub", data: xOnlyPubkey)
+        
+        return NostrIdentity(
+            privateKey: schnorrKey.dataRepresentation,
+            publicKey: xOnlyPubkey, // Store x-only public key
+            npub: npub,
+            createdAt: Date()
+        )
+    }
+    
+    /// Initialize from existing private key data
+    init(privateKeyData: Data) throws {
+        let schnorrKey = try P256K.Schnorr.PrivateKey(dataRepresentation: privateKeyData)
+        let xOnlyPubkey = Data(schnorrKey.xonly.bytes)
+        
+        self.privateKey = privateKeyData
+        self.publicKey = xOnlyPubkey
+        self.npub = try Bech32.encode(hrp: "npub", data: xOnlyPubkey)
+        self.createdAt = Date()
+    }
+    
+    /// Get signing key for event signatures
+    func signingKey() throws -> P256K.Signing.PrivateKey {
+        try P256K.Signing.PrivateKey(dataRepresentation: privateKey)
+    }
+    
+    /// Get Schnorr signing key for Nostr event signatures
+    func schnorrSigningKey() throws -> P256K.Schnorr.PrivateKey {
+        try P256K.Schnorr.PrivateKey(dataRepresentation: privateKey)
+    }
+    
+    /// Get hex-encoded public key (for Nostr events)
+    var publicKeyHex: String {
+        // Public key is already stored as x-only (32 bytes)
+        return publicKey.hexEncodedString()
+    }
+}

bitchat/Nostr/NostrIdentityBridge.swift

@@ -0,0 +1,157 @@
+import Foundation
+import CryptoKit
+
+/// Bridge between Noise and Nostr identities
+final class NostrIdentityBridge {
+    private let keychainService = "chat.bitchat.nostr"
+    private let currentIdentityKey = "nostr-current-identity"
+    private let deviceSeedKey = "nostr-device-seed"
+    // In-memory cache to avoid transient keychain access issues
+    private var deviceSeedCache: Data?
+    // Cache derived identities to avoid repeated crypto during view rendering
+    private var derivedIdentityCache: [String: NostrIdentity] = [:]
+    private let cacheLock = NSLock()
+
+    private let keychain: KeychainHelperProtocol
+
+    init(keychain: KeychainHelperProtocol = KeychainHelper()) {
+        self.keychain = keychain
+    }
+    
+    /// Get or create the current Nostr identity
+    func getCurrentNostrIdentity() throws -> NostrIdentity? {
+        // Check if we already have a Nostr identity
+        if let existingData = keychain.load(key: currentIdentityKey, service: keychainService),
+           let identity = try? JSONDecoder().decode(NostrIdentity.self, from: existingData) {
+            return identity
+        }
+        
+        // Generate new Nostr identity
+        let nostrIdentity = try NostrIdentity.generate()
+        
+        // Store it
+        let data = try JSONEncoder().encode(nostrIdentity)
+        keychain.save(key: currentIdentityKey, data: data, service: keychainService, accessible: nil)
+        
+        return nostrIdentity
+    }
+    
+    /// Associate a Nostr identity with a Noise public key (for favorites)
+    func associateNostrIdentity(_ nostrPubkey: String, with noisePublicKey: Data) {
+        let key = "nostr-noise-\(noisePublicKey.base64EncodedString())"
+        if let data = nostrPubkey.data(using: .utf8) {
+            keychain.save(key: key, data: data, service: keychainService, accessible: nil)
+        }
+    }
+    
+    /// Get Nostr public key associated with a Noise public key
+    func getNostrPublicKey(for noisePublicKey: Data) -> String? {
+        let key = "nostr-noise-\(noisePublicKey.base64EncodedString())"
+        guard let data = keychain.load(key: key, service: keychainService),
+              let pubkey = String(data: data, encoding: .utf8) else {
+            return nil
+        }
+        return pubkey
+    }
+    
+    /// Clear all Nostr identity associations and current identity
+    func clearAllAssociations() {
+        let query: [String: Any] = [
+            kSecClass as String: kSecClassGenericPassword,
+            kSecAttrService as String: keychainService,
+            kSecMatchLimit as String: kSecMatchLimitAll,
+            kSecReturnAttributes as String: true
+        ]
+
+        var result: AnyObject?
+        let status = SecItemCopyMatching(query as CFDictionary, &result)
+        if status == errSecSuccess, let items = result as? [[String: Any]] {
+            for item in items {
+                var deleteQuery: [String: Any] = [
+                    kSecClass as String: kSecClassGenericPassword,
+                    kSecAttrService as String: keychainService
+                ]
+                if let account = item[kSecAttrAccount as String] as? String {
+                    deleteQuery[kSecAttrAccount as String] = account
+                }
+                SecItemDelete(deleteQuery as CFDictionary)
+            }
+        } else if status == errSecItemNotFound {
+            // nothing persisted; no action needed
+        }
+
+        deviceSeedCache = nil
+    }
+
+    // MARK: - Per-Geohash Identities (Location Channels)
+
+    /// Returns a stable device seed used to derive unlinkable per-geohash identities.
+    /// Stored only on device keychain.
+    private func getOrCreateDeviceSeed() -> Data {
+        if let cached = deviceSeedCache { return cached }
+        if let existing = keychain.load(key: deviceSeedKey, service: keychainService) {
+            // Migrate to AfterFirstUnlockThisDeviceOnly for stability during lock
+            keychain.save(key: deviceSeedKey, data: existing, service: keychainService, accessible: kSecAttrAccessibleAfterFirstUnlockThisDeviceOnly)
+            deviceSeedCache = existing
+            return existing
+        }
+        var seed = Data(count: 32)
+        _ = seed.withUnsafeMutableBytes { ptr in
+            SecRandomCopyBytes(kSecRandomDefault, 32, ptr.baseAddress!)
+        }
+        // Ensure availability after first unlock to prevent unintended rotation when locked
+        keychain.save(key: deviceSeedKey, data: seed, service: keychainService, accessible: kSecAttrAccessibleAfterFirstUnlockThisDeviceOnly)
+        deviceSeedCache = seed
+        return seed
+    }
+
+    /// Derive a deterministic, unlinkable Nostr identity for a given geohash.
+    /// Uses HMAC-SHA256(deviceSeed, geohash) as private key material, with fallback rehashing
+    /// if the candidate is not a valid secp256k1 private key.
+    func deriveIdentity(forGeohash geohash: String) throws -> NostrIdentity {
+        // Check cache first to avoid repeated crypto + keychain I/O during view rendering
+        cacheLock.lock()
+        if let cached = derivedIdentityCache[geohash] {
+            cacheLock.unlock()
+            return cached
+        }
+        cacheLock.unlock()
+
+        let seed = getOrCreateDeviceSeed()
+        guard let msg = geohash.data(using: .utf8) else {
+            throw NSError(domain: "NostrIdentity", code: -1, userInfo: [NSLocalizedDescriptionKey: "Invalid geohash string"])
+        }
+
+        func candidateKey(iteration: UInt32) -> Data {
+            var input = Data(msg)
+            var iterBE = iteration.bigEndian
+            withUnsafeBytes(of: &iterBE) { bytes in
+                input.append(contentsOf: bytes)
+            }
+            let code = HMAC<SHA256>.authenticationCode(for: input, using: SymmetricKey(data: seed))
+            return Data(code)
+        }
+
+        // Try a few iterations to ensure a valid key can be formed
+        for i in 0..<10 {
+            let keyData = candidateKey(iteration: UInt32(i))
+            if let identity = try? NostrIdentity(privateKeyData: keyData) {
+                // Cache the result
+                cacheLock.lock()
+                derivedIdentityCache[geohash] = identity
+                cacheLock.unlock()
+                return identity
+            }
+        }
+        // As a final fallback, hash the seed+msg and try again
+        let fallback = (seed + msg).sha256Hash()
+        let identity = try NostrIdentity(privateKeyData: fallback)
+
+        // Cache the result
+        cacheLock.lock()
+        derivedIdentityCache[geohash] = identity
+        cacheLock.unlock()
+
+        return identity
+    }
+}

bitchat/Nostr/NostrProtocol.swift

@@ -0,0 +1,571 @@
+import BitLogger
+import Foundation
+import CryptoKit
+import P256K
+import Security
+
+// Note: This file depends on Data extension from BinaryEncodingUtils.swift
+// Make sure BinaryEncodingUtils.swift is included in the target
+
+/// NIP-17 Protocol Implementation for Private Direct Messages
+struct NostrProtocol {
+    
+    /// Nostr event kinds
+    enum EventKind: Int {
+        case metadata = 0
+        case textNote = 1
+        case dm = 14 // NIP-17 DM rumor kind
+        case seal = 13 // NIP-17 sealed event
+        case giftWrap = 1059 // NIP-59 gift wrap
+        case ephemeralEvent = 20000
+    }
+    
+    /// Create a NIP-17 private message
+    static func createPrivateMessage(
+        content: String,
+        recipientPubkey: String,
+        senderIdentity: NostrIdentity
+    ) throws -> NostrEvent {
+        
+        // Creating private message
+        
+        // 1. Create the rumor (unsigned event)
+        let rumor = NostrEvent(
+            pubkey: senderIdentity.publicKeyHex,
+            createdAt: Date(),
+            kind: .dm, // NIP-17: DM rumor kind 14
+            tags: [],
+            content: content
+        )
+        
+        // 2. Create ephemeral key for this message
+        let ephemeralKey = try P256K.Schnorr.PrivateKey()
+        // Created ephemeral key for seal
+        
+        // 3. Seal the rumor (encrypt to recipient)
+        let sealedEvent = try createSeal(
+            rumor: rumor,
+            recipientPubkey: recipientPubkey,
+            senderKey: ephemeralKey
+        )
+        
+        // 4. Gift wrap the sealed event (encrypt to recipient again)
+        let giftWrap = try createGiftWrap(
+            seal: sealedEvent,
+            recipientPubkey: recipientPubkey,
+            senderKey: ephemeralKey
+        )
+        
+        // Created gift wrap
+        
+        return giftWrap
+    }
+    
+    /// Decrypt a received NIP-17 message
+    /// Returns the content, sender pubkey, and the actual message timestamp (not the randomized gift wrap timestamp)
+    static func decryptPrivateMessage(
+        giftWrap: NostrEvent,
+        recipientIdentity: NostrIdentity
+    ) throws -> (content: String, senderPubkey: String, timestamp: Int) {
+        
+        // Starting decryption
+        
+        // 1. Unwrap the gift wrap
+        let seal: NostrEvent
+        do {
+            seal = try unwrapGiftWrap(
+                giftWrap: giftWrap,
+                recipientKey: recipientIdentity.schnorrSigningKey()
+            )
+            // Successfully unwrapped gift wrap
+        } catch {
+            SecureLogger.error("❌ Failed to unwrap gift wrap: \(error)", category: .session)
+            throw error
+        }
+        
+        // 2. Open the seal
+        let rumor: NostrEvent
+        do {
+            rumor = try openSeal(
+                seal: seal,
+                recipientKey: recipientIdentity.schnorrSigningKey()
+            )
+            // Successfully opened seal
+        } catch {
+            SecureLogger.error("❌ Failed to open seal: \(error)", category: .session)
+            throw error
+        }
+        
+        return (content: rumor.content, senderPubkey: rumor.pubkey, timestamp: rumor.created_at)
+    }
+
+    /// Create a geohash-scoped ephemeral public message (kind 20000)
+    static func createEphemeralGeohashEvent(
+        content: String,
+        geohash: String,
+        senderIdentity: NostrIdentity,
+        nickname: String? = nil,
+        teleported: Bool = false
+    ) throws -> NostrEvent {
+        var tags = [["g", geohash]]
+        if let nickname = nickname?.trimmingCharacters(in: .whitespacesAndNewlines), !nickname.isEmpty {
+            tags.append(["n", nickname])
+        }
+        if teleported {
+            tags.append(["t", "teleport"])
+        }
+        let event = NostrEvent(
+            pubkey: senderIdentity.publicKeyHex,
+            createdAt: Date(),
+            kind: .ephemeralEvent,
+            tags: tags,
+            content: content
+        )
+        let schnorrKey = try senderIdentity.schnorrSigningKey()
+        return try event.sign(with: schnorrKey)
+    }
+
+    /// Create a persistent location note (kind 1: text note) tagged to a street-level geohash.
+    static func createGeohashTextNote(
+        content: String,
+        geohash: String,
+        senderIdentity: NostrIdentity,
+        nickname: String? = nil
+    ) throws -> NostrEvent {
+        var tags = [["g", geohash]]
+        if let nickname = nickname?.trimmingCharacters(in: .whitespacesAndNewlines), !nickname.isEmpty {
+            tags.append(["n", nickname])
+        }
+        let event = NostrEvent(
+            pubkey: senderIdentity.publicKeyHex,
+            createdAt: Date(),
+            kind: .textNote,
+            tags: tags,
+            content: content
+        )
+        let schnorrKey = try senderIdentity.schnorrSigningKey()
+        return try event.sign(with: schnorrKey)
+    }
+    
+    // MARK: - Private Methods
+    
+    private static func createSeal(
+        rumor: NostrEvent,
+        recipientPubkey: String,
+        senderKey: P256K.Schnorr.PrivateKey
+    ) throws -> NostrEvent {
+        
+        let rumorJSON = try rumor.jsonString()
+        let encrypted = try encrypt(
+            plaintext: rumorJSON,
+            recipientPubkey: recipientPubkey,
+            senderKey: senderKey
+        )
+        
+        let seal = NostrEvent(
+            pubkey: Data(senderKey.xonly.bytes).hexEncodedString(),
+            createdAt: randomizedTimestamp(),
+            kind: .seal,
+            tags: [],
+            content: encrypted
+        )
+        
+        // Sign the seal with the sender's Schnorr private key
+        return try seal.sign(with: senderKey)
+    }
+    
+    private static func createGiftWrap(
+        seal: NostrEvent,
+        recipientPubkey: String,
+        senderKey: P256K.Schnorr.PrivateKey  // This is the ephemeral key used for the seal
+    ) throws -> NostrEvent {
+        
+        let sealJSON = try seal.jsonString()
+        
+        // Create new ephemeral key for gift wrap
+        let wrapKey = try P256K.Schnorr.PrivateKey()
+        // Creating gift wrap with ephemeral key
+        
+        // Encrypt the seal with the new ephemeral key (not the seal's key)
+        let encrypted = try encrypt(
+            plaintext: sealJSON,
+            recipientPubkey: recipientPubkey,
+            senderKey: wrapKey  // Use the gift wrap ephemeral key
+        )
+        
+        let giftWrap = NostrEvent(
+            pubkey: Data(wrapKey.xonly.bytes).hexEncodedString(),
+            createdAt: randomizedTimestamp(),
+            kind: .giftWrap,
+            tags: [["p", recipientPubkey]], // Tag recipient
+            content: encrypted
+        )
+        
+        // Sign the gift wrap with the wrap Schnorr private key
+        return try giftWrap.sign(with: wrapKey)
+    }
+    
+    private static func unwrapGiftWrap(
+        giftWrap: NostrEvent,
+        recipientKey: P256K.Schnorr.PrivateKey
+    ) throws -> NostrEvent {
+        
+        // Unwrapping gift wrap
+        
+        let decrypted = try decrypt(
+            ciphertext: giftWrap.content,
+            senderPubkey: giftWrap.pubkey,
+            recipientKey: recipientKey
+        )
+        
+        guard let data = decrypted.data(using: .utf8),
+              let sealDict = try JSONSerialization.jsonObject(with: data) as? [String: Any] else {
+            throw NostrError.invalidEvent
+        }
+        
+        let seal = try NostrEvent(from: sealDict)
+        // Unwrapped seal
+        
+        return seal
+    }
+    
+    private static func openSeal(
+        seal: NostrEvent,
+        recipientKey: P256K.Schnorr.PrivateKey
+    ) throws -> NostrEvent {
+        
+        let decrypted = try decrypt(
+            ciphertext: seal.content,
+            senderPubkey: seal.pubkey,
+            recipientKey: recipientKey
+        )
+        
+        guard let data = decrypted.data(using: .utf8),
+              let rumorDict = try JSONSerialization.jsonObject(with: data) as? [String: Any] else {
+            throw NostrError.invalidEvent
+        }
+        
+        return try NostrEvent(from: rumorDict)
+    }
+    
+    // MARK: - Encryption (NIP-44 v2)
+    
+    private static func encrypt(
+        plaintext: String,
+        recipientPubkey: String,
+        senderKey: P256K.Schnorr.PrivateKey
+    ) throws -> String {
+        
+        guard let recipientPubkeyData = Data(hexString: recipientPubkey) else {
+            throw NostrError.invalidPublicKey
+        }
+        
+        // Encrypting message (NIP-44 v2: XChaCha20-Poly1305, versioned)
+        
+        // Derive shared secret
+        let sharedSecret = try deriveSharedSecret(
+            privateKey: senderKey,
+            publicKey: recipientPubkeyData
+        )
+        // Derive NIP-44 v2 symmetric key (HKDF-SHA256 with label in info)
+        let key = try deriveNIP44V2Key(from: sharedSecret)
+        
+        // 24-byte random nonce for XChaCha20-Poly1305
+        var nonce24 = Data(count: 24)
+        _ = nonce24.withUnsafeMutableBytes { ptr in
+            SecRandomCopyBytes(kSecRandomDefault, 24, ptr.baseAddress!)
+        }
+        
+        let pt = Data(plaintext.utf8)
+        let sealed = try XChaCha20Poly1305Compat.seal(plaintext: pt, key: key, nonce24: nonce24)
+        
+        // v2: base64url(nonce24 || ciphertext || tag)
+        var combined = Data()
+        combined.append(nonce24)
+        combined.append(sealed.ciphertext)
+        combined.append(sealed.tag)
+        return "v2:" + base64URLEncode(combined)
+    }
+    
+    private static func decrypt(
+        ciphertext: String,
+        senderPubkey: String,
+        recipientKey: P256K.Schnorr.PrivateKey
+    ) throws -> String {
+        // Expect NIP-44 v2 format
+        guard ciphertext.hasPrefix("v2:") else { throw NostrError.invalidCiphertext }
+        let encoded = String(ciphertext.dropFirst(3))
+        guard let data = base64URLDecode(encoded),
+              data.count > (24 + 16),
+              let senderPubkeyData = Data(hexString: senderPubkey) else {
+            throw NostrError.invalidCiphertext
+        }
+
+        let nonce24 = data.prefix(24)
+        let rest = data.dropFirst(24)
+        let tag = rest.suffix(16)
+        let ct = rest.dropLast(16)
+
+        // Try decryption with even-Y then odd-Y when sender pubkey is x-only
+        func attemptDecrypt(using pubKeyData: Data) throws -> Data {
+            let ss = try deriveSharedSecret(privateKey: recipientKey, publicKey: pubKeyData)
+            let key = try deriveNIP44V2Key(from: ss)
+            return try XChaCha20Poly1305Compat.open(
+                ciphertext: Data(ct),
+                tag: Data(tag),
+                key: key,
+                nonce24: Data(nonce24)
+            )
+        }
+
+        // If 32 bytes (x-only) try both parities, otherwise single try
+        if senderPubkeyData.count == 32 {
+            let even = Data([0x02]) + senderPubkeyData
+            if let pt = try? attemptDecrypt(using: even) {
+                return String(data: pt, encoding: .utf8) ?? ""
+            }
+            let odd = Data([0x03]) + senderPubkeyData
+            let pt = try attemptDecrypt(using: odd)
+            return String(data: pt, encoding: .utf8) ?? ""
+        } else {
+            let pt = try attemptDecrypt(using: senderPubkeyData)
+            return String(data: pt, encoding: .utf8) ?? ""
+        }
+    }
+    
+    private static func deriveSharedSecret(
+        privateKey: P256K.Schnorr.PrivateKey,
+        publicKey: Data
+    ) throws -> Data {
+        // Deriving shared secret
+        
+        // Convert Schnorr private key to KeyAgreement private key
+        let keyAgreementPrivateKey = try P256K.KeyAgreement.PrivateKey(
+            dataRepresentation: privateKey.dataRepresentation
+        )
+        
+        // Create KeyAgreement public key from the public key data
+        // For ECDH, we need the full 33-byte compressed public key (with 0x02 or 0x03 prefix)
+        var fullPublicKey = Data()
+        if publicKey.count == 32 { // X-only key, need to add prefix
+            // For x-only keys in Nostr/Bitcoin, we need to try both possible Y coordinates
+            // First try with even Y (0x02 prefix)
+            fullPublicKey.append(0x02)
+            fullPublicKey.append(publicKey)
+            // Trying with even Y coordinate
+        } else {
+            fullPublicKey = publicKey
+        }
+        
+        // Try to create public key, if it fails with even Y, try odd Y
+        let keyAgreementPublicKey: P256K.KeyAgreement.PublicKey
+        do {
+            keyAgreementPublicKey = try P256K.KeyAgreement.PublicKey(
+                dataRepresentation: fullPublicKey,
+                format: .compressed
+            )
+        } catch {
+            if publicKey.count == 32 {
+                // Try with odd Y (0x03 prefix)
+                // Even Y failed, trying odd Y
+                fullPublicKey = Data()
+                fullPublicKey.append(0x03)
+                fullPublicKey.append(publicKey)
+                keyAgreementPublicKey = try P256K.KeyAgreement.PublicKey(
+                    dataRepresentation: fullPublicKey,
+                    format: .compressed
+                )
+            } else {
+                throw error
+            }
+        }
+        
+        // Perform ECDH
+        let sharedSecret = try keyAgreementPrivateKey.sharedSecretFromKeyAgreement(
+            with: keyAgreementPublicKey,
+            format: .compressed
+        )
+        
+        // Convert SharedSecret to Data
+        let sharedSecretData = sharedSecret.withUnsafeBytes { Data($0) }
+        // ECDH shared secret derived
+        
+        // Return raw ECDH shared secret; HKDF is applied by deriveNIP44V2Key
+        return sharedSecretData
+    }
+    
+    // Direct version that doesn't try to add prefixes
+    private static func deriveSharedSecretDirect(
+        privateKey: P256K.Schnorr.PrivateKey,
+        publicKey: Data
+    ) throws -> Data {
+        // Direct shared secret calculation
+        
+        // Convert Schnorr private key to KeyAgreement private key
+        let keyAgreementPrivateKey = try P256K.KeyAgreement.PrivateKey(
+            dataRepresentation: privateKey.dataRepresentation
+        )
+        
+        // Use the public key as-is (should already have prefix)
+        let keyAgreementPublicKey = try P256K.KeyAgreement.PublicKey(
+            dataRepresentation: publicKey,
+            format: .compressed
+        )
+        
+        // Perform ECDH
+        let sharedSecret = try keyAgreementPrivateKey.sharedSecretFromKeyAgreement(
+            with: keyAgreementPublicKey,
+            format: .compressed
+        )
+        
+        // Convert SharedSecret to Data
+        let sharedSecretData = sharedSecret.withUnsafeBytes { Data($0) }
+        
+        // Return raw ECDH shared secret; HKDF is applied by deriveNIP44V2Key
+        return sharedSecretData
+    }
+    
+    private static func randomizedTimestamp() -> Date {
+        // Add random offset to current time for privacy
+        // This prevents timing correlation attacks while the actual message timestamp
+        // is preserved in the encrypted rumor
+        let offset = TimeInterval.random(in: -900...900) // +/- 15 minutes
+        let now = Date()
+        let randomized = now.addingTimeInterval(offset)
+        
+        // Log with explicit UTC and local time for debugging
+        let formatter = DateFormatter()
+        //
+        formatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
+        formatter.timeZone = TimeZone(abbreviation: "UTC")
+        
+        formatter.timeZone = TimeZone.current
+        
+        // Timestamp randomized for privacy
+        
+        return randomized
+    }
+}
+
+/// Nostr Event structure
+struct NostrEvent: Codable {
+    var id: String
+    let pubkey: String
+    let created_at: Int
+    let kind: Int
+    let tags: [[String]]
+    let content: String
+    var sig: String?
+    
+    init(
+        pubkey: String,
+        createdAt: Date,
+        kind: NostrProtocol.EventKind,
+        tags: [[String]],
+        content: String
+    ) {
+        self.pubkey = pubkey
+        self.created_at = Int(createdAt.timeIntervalSince1970)
+        self.kind = kind.rawValue
+        self.tags = tags
+        self.content = content
+        self.sig = nil
+        self.id = "" // Will be set during signing
+    }
+    
+    init(from dict: [String: Any]) throws {
+        guard let pubkey = dict["pubkey"] as? String,
+              let createdAt = dict["created_at"] as? Int,
+              let kind = dict["kind"] as? Int,
+              let tags = dict["tags"] as? [[String]],
+              let content = dict["content"] as? String else {
+            throw NostrError.invalidEvent
+        }
+        
+        self.id = dict["id"] as? String ?? ""
+        self.pubkey = pubkey
+        self.created_at = createdAt
+        self.kind = kind
+        self.tags = tags
+        self.content = content
+        self.sig = dict["sig"] as? String
+    }
+    
+    func sign(with key: P256K.Schnorr.PrivateKey) throws -> NostrEvent {
+        let (eventId, eventIdHash) = try calculateEventId()
+        
+        // Sign with Schnorr (BIP-340)
+        var messageBytes = [UInt8](eventIdHash)
+        var auxRand = [UInt8](repeating: 0, count: 32)
+        _ = auxRand.withUnsafeMutableBytes { ptr in
+            SecRandomCopyBytes(kSecRandomDefault, 32, ptr.baseAddress!)
+        }
+        let schnorrSignature = try key.signature(message: &messageBytes, auxiliaryRand: &auxRand)
+        
+        let signatureHex = schnorrSignature.dataRepresentation.hexEncodedString()
+        
+        var signed = self
+        signed.id = eventId
+        signed.sig = signatureHex
+        return signed
+    }
+    
+    private func calculateEventId() throws -> (String, Data) {
+        let serialized = [
+            0,
+            pubkey,
+            created_at,
+            kind,
+            tags,
+            content
+        ] as [Any]
+        
+        let data = try JSONSerialization.data(withJSONObject: serialized, options: [.withoutEscapingSlashes])
+        return (data.sha256Fingerprint(), data.sha256Hash())
+    }
+    
+    func jsonString() throws -> String {
+        let encoder = JSONEncoder()
+        encoder.outputFormatting = [.withoutEscapingSlashes]
+        let data = try encoder.encode(self)
+        return String(data: data, encoding: .utf8) ?? ""
+    }
+}
+
+enum NostrError: Error {
+    case invalidPublicKey
+    case invalidPrivateKey
+    case invalidEvent
+    case invalidCiphertext
+    case signingFailed
+    case encryptionFailed
+}
+
+// MARK: - NIP-44 v2 helpers (XChaCha20-Poly1305 + base64url)
+
+private extension NostrProtocol {
+    static func base64URLEncode(_ data: Data) -> String {
+        return data.base64EncodedString()
+            .replacingOccurrences(of: "+", with: "-")
+            .replacingOccurrences(of: "/", with: "_")
+            .replacingOccurrences(of: "=", with: "")
+    }
+
+    static func base64URLDecode(_ s: String) -> Data? {
+        var str = s
+        let pad = (4 - (str.count % 4)) % 4
+        if pad > 0 { str += String(repeating: "=", count: pad) }
+        str = str.replacingOccurrences(of: "-", with: "+").replacingOccurrences(of: "_", with: "/")
+        return Data(base64Encoded: str)
+    }
+
+    static func deriveNIP44V2Key(from sharedSecretData: Data) throws -> Data {
+        let derivedKey = HKDF<CryptoKit.SHA256>.deriveKey(
+            inputKeyMaterial: SymmetricKey(data: sharedSecretData),
+            salt: Data(),
+            info: "nip44-v2".data(using: .utf8)!,
+            outputByteCount: 32
+        )
+        return derivedKey.withUnsafeBytes { Data($0) }
+    }
+}

bitchat/Nostr/NostrRelayManager.swift

@@ -0,0 +1,939 @@
+import BitLogger
+import Foundation
+import Network
+import Combine
+import Tor
+
+/// Manages WebSocket connections to Nostr relays
+@MainActor
+final class NostrRelayManager: ObservableObject {
+    static let shared = NostrRelayManager()
+    // Track gift-wraps (kind 1059) we initiated so we can log OK acks at info
+    private(set) static var pendingGiftWrapIDs = Set<String>()
+    static func registerPendingGiftWrap(id: String) {
+        pendingGiftWrapIDs.insert(id)
+    }
+    
+    struct Relay: Identifiable {
+        let id = UUID()
+        let url: String
+        var isConnected: Bool = false
+        var lastError: Error?
+        var lastConnectedAt: Date?
+        var messagesSent: Int = 0
+        var messagesReceived: Int = 0
+        var reconnectAttempts: Int = 0
+        var lastDisconnectedAt: Date?
+        var nextReconnectTime: Date?
+    }
+    
+    // Default relay list (can be customized)
+    private static let defaultRelays = [
+        "wss://relay.damus.io",
+        "wss://nos.lol",
+        "wss://relay.primal.net",
+        "wss://offchain.pub",
+        "wss://nostr21.com"
+        // For local testing, you can add: "ws://localhost:8080"
+    ]
+    private static let defaultRelaySet = Set(defaultRelays)
+    
+    @Published private(set) var relays: [Relay] = []
+    @Published private(set) var isConnected = false
+    
+    private var allowDefaultRelays: Bool = false
+    private var hasMutualFavorites: Bool = false
+    private var hasLocationPermission: Bool = false
+    private var connections: [String: URLSessionWebSocketTask] = [:]
+    private var subscriptions: [String: Set<String>] = [:] // relay URL -> active subscription IDs
+    private var pendingSubscriptions: [String: [String: String]] = [:] // relay URL -> (subscription id -> encoded REQ JSON)
+    private var messageHandlers: [String: (NostrEvent) -> Void] = [:]
+    // Coalesce duplicate subscribe requests for the same id within a short window
+    private var subscribeCoalesce: [String: Date] = [:]
+    private var cancellables = Set<AnyCancellable>()
+
+    // Track EOSE per subscription to signal when initial stored events are done
+    private struct EOSETracker {
+        var pendingRelays: Set<String>
+        var callback: () -> Void
+        var timer: Timer?
+    }
+    private var eoseTrackers: [String: EOSETracker] = [:]
+    
+    // Message queue for reliability
+    // Pending sends held only for relays that are not yet connected.
+    private struct PendingSend {
+        var event: NostrEvent
+        var pendingRelays: Set<String>
+    }
+    private var messageQueue: [PendingSend] = []
+    private let messageQueueLock = NSLock()
+    private let encoder = JSONEncoder()
+    private let decoder = JSONDecoder()
+    private var networkService: NetworkActivationService { NetworkActivationService.shared }
+    private var shouldUseTor: Bool { networkService.userTorEnabled }
+    
+    // Exponential backoff configuration
+    private let initialBackoffInterval: TimeInterval = TransportConfig.nostrRelayInitialBackoffSeconds
+    private let maxBackoffInterval: TimeInterval = TransportConfig.nostrRelayMaxBackoffSeconds
+    private let backoffMultiplier: Double = TransportConfig.nostrRelayBackoffMultiplier
+    private let maxReconnectAttempts = TransportConfig.nostrRelayMaxReconnectAttempts
+    
+    // Reconnection timer
+    private var reconnectionTimer: Timer?
+    // Bump generation to invalidate scheduled reconnects when we reset/disconnect
+    private var connectionGeneration: Int = 0
+    
+    init() {
+        hasMutualFavorites = !FavoritesPersistenceService.shared.mutualFavorites.isEmpty
+        hasLocationPermission = LocationChannelManager.shared.permissionState == .authorized
+        applyDefaultRelayPolicy(force: true)
+        // Deterministic JSON shape for outbound requests
+        self.encoder.outputFormatting = .sortedKeys
+        FavoritesPersistenceService.shared.$mutualFavorites
+            .receive(on: DispatchQueue.main)
+            .sink { [weak self] favorites in
+                guard let self = self else { return }
+                self.hasMutualFavorites = !favorites.isEmpty
+                self.applyDefaultRelayPolicy()
+            }
+            .store(in: &cancellables)
+        LocationChannelManager.shared.$permissionState
+            .receive(on: DispatchQueue.main)
+            .sink { [weak self] state in
+                guard let self = self else { return }
+                let authorized = (state == .authorized)
+                if authorized == self.hasLocationPermission { return }
+                self.hasLocationPermission = authorized
+                self.applyDefaultRelayPolicy()
+            }
+            .store(in: &cancellables)
+    }
+    
+    /// Connect to all configured relays
+    func connect() {
+        // Global network policy gate
+        guard networkService.activationAllowed else { return }
+        if shouldUseTor {
+            // Ensure Tor is started early and wait for readiness off-main; then hop back to connect.
+            Task.detached {
+                let ready = await TorManager.shared.awaitReady()
+                await MainActor.run {
+                    if !ready {
+                        SecureLogger.error("❌ Tor not ready; aborting relay connections (fail-closed)", category: .session)
+                        return
+                    }
+                    SecureLogger.debug("🌐 Connecting to \(self.relays.count) Nostr relays (via Tor)", category: .session)
+                    for relay in self.relays {
+                        self.connectToRelay(relay.url)
+                    }
+                }
+            }
+        } else {
+            SecureLogger.debug("🌐 Connecting to \(self.relays.count) Nostr relays (direct)", category: .session)
+            for relay in self.relays {
+                connectToRelay(relay.url)
+            }
+        }
+    }
+    
+    /// Disconnect from all relays
+    func disconnect() {
+        connectionGeneration &+= 1
+        for (_, task) in connections {
+            task.cancel(with: .goingAway, reason: nil)
+        }
+        connections.removeAll()
+        // Clear known subscriptions and any queued subs since connections are gone
+        subscriptions.removeAll()
+        pendingSubscriptions.removeAll()
+        updateConnectionStatus()
+    }
+    
+    /// Ensure connections exist to the given relay URLs (idempotent).
+    func ensureConnections(to relayUrls: [String]) {
+        // Global network policy gate
+        guard networkService.activationAllowed else { return }
+        let targets = allowedRelayList(from: relayUrls)
+        guard !targets.isEmpty else { return }
+        if shouldUseTor && TorManager.shared.torEnforced && !TorManager.shared.isReady {
+            // Defer until Tor is fully ready; avoid queuing connection attempts early
+            Task.detached { [weak self] in
+                guard let self = self else { return }
+                let ready = await TorManager.shared.awaitReady()
+                await MainActor.run { if ready { self.ensureConnections(to: relayUrls) } }
+            }
+            return
+        }
+        var existing = Set(relays.map { $0.url })
+        for url in targets where !existing.contains(url) {
+            relays.append(Relay(url: url))
+            existing.insert(url)
+        }
+        for url in targets where connections[url] == nil {
+            connectToRelay(url)
+        }
+    }
+
+    /// Send an event to specified relays (or all if none specified)
+    func sendEvent(_ event: NostrEvent, to relayUrls: [String]? = nil) {
+        // Global network policy gate
+        guard networkService.activationAllowed else { return }
+        if shouldUseTor && TorManager.shared.torEnforced && !TorManager.shared.isReady {
+            // Defer sends until Tor is ready to avoid premature queueing
+            Task.detached { [weak self] in
+                guard let self = self else { return }
+                let ready = await TorManager.shared.awaitReady()
+                await MainActor.run { if ready { self.sendEvent(event, to: relayUrls) } }
+            }
+            return
+        }
+        let requestedRelays = relayUrls ?? Self.defaultRelays
+        let targetRelays = allowedRelayList(from: requestedRelays)
+        guard !targetRelays.isEmpty else { return }
+        ensureConnections(to: targetRelays)
+
+        // Attempt immediate send to relays with active connections; queue the rest
+        var stillPending = Set<String>()
+        for relayUrl in targetRelays {
+            if let connection = connections[relayUrl] {
+                sendToRelay(event: event, connection: connection, relayUrl: relayUrl)
+            } else {
+                stillPending.insert(relayUrl)
+            }
+        }
+        if !stillPending.isEmpty {
+            messageQueueLock.lock()
+            messageQueue.append(PendingSend(event: event, pendingRelays: stillPending))
+            messageQueueLock.unlock()
+        }
+    }
+
+    /// Try to flush any queued messages for relays that are now connected.
+    private func flushMessageQueue(for relayUrl: String? = nil) {
+        messageQueueLock.lock()
+        defer { messageQueueLock.unlock() }
+        guard !messageQueue.isEmpty else { return }
+        if let target = relayUrl {
+            // Flush only for a specific relay
+            for i in (0..<messageQueue.count).reversed() {
+                var item = messageQueue[i]
+                if item.pendingRelays.contains(target), let conn = connections[target] {
+                    sendToRelay(event: item.event, connection: conn, relayUrl: target)
+                    item.pendingRelays.remove(target)
+                    if item.pendingRelays.isEmpty {
+                        messageQueue.remove(at: i)
+                    } else {
+                        messageQueue[i] = item
+                    }
+                }
+            }
+        } else {
+            // Flush for any relays that now have connections
+            for i in (0..<messageQueue.count).reversed() {
+                var item = messageQueue[i]
+                for url in item.pendingRelays {
+                    if let conn = connections[url] {
+                        sendToRelay(event: item.event, connection: conn, relayUrl: url)
+                        item.pendingRelays.remove(url)
+                    }
+                }
+                if item.pendingRelays.isEmpty {
+                    messageQueue.remove(at: i)
+                } else {
+                    messageQueue[i] = item
+                }
+            }
+        }
+    }
+    
+    /// Subscribe to events matching a filter. If `relayUrls` provided, targets only those relays.
+    func subscribe(
+        filter: NostrFilter,
+        id: String = UUID().uuidString,
+        relayUrls: [String]? = nil,
+        handler: @escaping (NostrEvent) -> Void,
+        onEOSE: (() -> Void)? = nil
+    ) {
+        // Global network policy gate
+        guard networkService.activationAllowed else { return }
+        // Coalesce rapid duplicate subscribe requests only if a handler already exists
+        let now = Date()
+        if messageHandlers[id] != nil {
+            if let last = subscribeCoalesce[id], now.timeIntervalSince(last) < 1.0 {
+                return
+            }
+        }
+        subscribeCoalesce[id] = now
+        if shouldUseTor && TorManager.shared.torEnforced && !TorManager.shared.isReady {
+            // Defer subscription setup until Tor is ready; avoid queuing subs early
+            Task.detached { [weak self] in
+                guard let self = self else { return }
+                let ready = await TorManager.shared.awaitReady()
+                await MainActor.run {
+                    if ready {
+                        self.subscribe(filter: filter, id: id, relayUrls: relayUrls, handler: handler)
+                    }
+                }
+            }
+            return
+        }
+        messageHandlers[id] = handler
+        
+        let req = NostrRequest.subscribe(id: id, filters: [filter])
+        
+        do {
+            let message = try encoder.encode(req)
+            guard let messageString = String(data: message, encoding: .utf8) else { 
+                SecureLogger.error("❌ Failed to encode subscription request", category: .session)
+                return 
+            }
+            
+            // SecureLogger.debug("📋 Subscription filter JSON: \(messageString.prefix(200))...", category: .session)
+            
+            // Target specific relays if provided; else default. Filter permanently failed relays.
+            let baseUrls = relayUrls ?? Self.defaultRelays
+            let candidateUrls = baseUrls.filter { !isPermanentlyFailed($0) }
+            let urls = allowedRelayList(from: candidateUrls)
+            // Always queue subscriptions; sending happens when a relay reports connected
+            let existingSet = Set(relays.map { $0.url })
+            for url in urls where !existingSet.contains(url) {
+                relays.append(Relay(url: url))
+            }
+            for url in candidateUrls {
+                var map = self.pendingSubscriptions[url] ?? [:]
+                map[id] = messageString
+                self.pendingSubscriptions[url] = map
+            }
+            // Initialize EOSE tracking if requested
+            if let onEOSE = onEOSE {
+                if urls.isEmpty {
+                    onEOSE()
+                } else {
+                    var tracker = EOSETracker(pendingRelays: Set(urls), callback: onEOSE, timer: nil)
+                    // Fallback timeout to avoid hanging if a relay never sends EOSE
+                    tracker.timer = Timer.scheduledTimer(withTimeInterval: 2.0, repeats: false) { [weak self] _ in
+                        Task { @MainActor in
+                            guard let self = self else { return }
+                            if let t = self.eoseTrackers[id] {
+                                t.timer?.invalidate()
+                                self.eoseTrackers.removeValue(forKey: id)
+                                onEOSE()
+                            }
+                        }
+                    }
+                    eoseTrackers[id] = tracker
+                }
+            }
+            SecureLogger.debug("📋 Queued subscription id=\(id) for \(urls.count) relay(s)", category: .session)
+            // Ensure we actually have sockets opening to these relays so queued REQs can flush
+            ensureConnections(to: urls)
+            // If some targets are already connected, flush immediately for them
+            for url in urls {
+                if let r = relays.first(where: { $0.url == url }), r.isConnected {
+                    flushPendingSubscriptions(for: url)
+                }
+            }
+        } catch {
+            SecureLogger.error("❌ Failed to encode subscription request: \(error)", category: .session)
+        }
+    }
+
+    private func applyDefaultRelayPolicy(force: Bool = false) {
+        let shouldAllow = hasMutualFavorites || hasLocationPermission
+        if !force && shouldAllow == allowDefaultRelays { return }
+        allowDefaultRelays = shouldAllow
+        if shouldAllow {
+            var existing = Set(relays.map { $0.url })
+            for url in Self.defaultRelays where !existing.contains(url) {
+                relays.append(Relay(url: url))
+                existing.insert(url)
+            }
+            if networkService.activationAllowed {
+                ensureConnections(to: Self.defaultRelays)
+            }
+        } else {
+            for url in Self.defaultRelays {
+                if let connection = connections[url] {
+                    connection.cancel(with: .goingAway, reason: nil)
+                }
+                connections.removeValue(forKey: url)
+                subscriptions.removeValue(forKey: url)
+            }
+            messageQueueLock.lock()
+            for index in (0..<messageQueue.count).reversed() {
+                var item = messageQueue[index]
+                item.pendingRelays.subtract(Self.defaultRelaySet)
+                if item.pendingRelays.isEmpty {
+                    messageQueue.remove(at: index)
+                } else {
+                    messageQueue[index] = item
+                }
+            }
+            messageQueueLock.unlock()
+            relays.removeAll { Self.defaultRelaySet.contains($0.url) }
+            updateConnectionStatus()
+        }
+    }
+
+    private func allowedRelayList(from urls: [String]) -> [String] {
+        var seen = Set<String>()
+        var result: [String] = []
+        for url in urls {
+            if !allowDefaultRelays && Self.defaultRelaySet.contains(url) { continue }
+            if seen.insert(url).inserted {
+                result.append(url)
+            }
+        }
+        return result
+    }
+    
+    /// Unsubscribe from a subscription
+    func unsubscribe(id: String) {
+        messageHandlers.removeValue(forKey: id)
+        // Allow immediate re-subscription by clearing coalescer timestamp
+        subscribeCoalesce.removeValue(forKey: id)
+        
+        let req = NostrRequest.close(id: id)
+        let message = try? encoder.encode(req)
+        
+        guard let messageData = message,
+              let messageString = String(data: messageData, encoding: .utf8) else { return }
+        
+        // Send unsubscribe to all relays
+        for (relayUrl, connection) in connections {
+            if subscriptions[relayUrl]?.contains(id) == true {
+                connection.send(.string(messageString)) { _ in
+                    Task { @MainActor in
+                        self.subscriptions[relayUrl]?.remove(id)
+                    }
+                }
+            }
+        }
+    }
+    
+    // MARK: - Private Methods
+    
+    private func connectToRelay(_ urlString: String) {
+        // Global network policy gate
+        guard networkService.activationAllowed else { return }
+        guard let url = URL(string: urlString) else { 
+            SecureLogger.warning("Invalid relay URL: \(urlString)", category: .session)
+            return 
+        }
+
+        // Avoid initiating connections while app is backgrounded; we'll reconnect on foreground
+        if shouldUseTor && TorManager.shared.torEnforced && !TorManager.shared.isForeground() {
+            return
+        }
+        
+        // Skip if we already have a connection object
+        if connections[urlString] != nil {
+            return
+        }
+        if isPermanentlyFailed(urlString) {
+            return
+        }
+        
+        // Attempting to connect to Nostr relay via the proxied session
+        
+        // If Tor is enforced but not ready, delay connection until it is.
+        if shouldUseTor && TorManager.shared.torEnforced && !TorManager.shared.isReady {
+            Task.detached { [weak self] in
+                guard let self = self else { return }
+                let ready = await TorManager.shared.awaitReady()
+                await MainActor.run {
+                    if ready { self.connectToRelay(urlString) }
+                    else { SecureLogger.error("❌ Tor not ready; skipping connection to \(urlString)", category: .session) }
+                }
+            }
+            return
+        }
+        
+        let session = TorURLSession.shared.session
+        let task = session.webSocketTask(with: url)
+        
+        connections[urlString] = task
+        task.resume()
+        
+        // Start receiving messages
+        receiveMessage(from: task, relayUrl: urlString)
+        
+        // Send initial ping to verify connection
+        task.sendPing { [weak self] error in
+            DispatchQueue.main.async {
+                if error == nil {
+                    SecureLogger.debug("✅ Connected to Nostr relay: \(urlString)", category: .session)
+                    self?.updateRelayStatus(urlString, isConnected: true)
+                    // Flush any pending subscriptions for this relay
+                    self?.flushPendingSubscriptions(for: urlString)
+                } else {
+                    SecureLogger.error("❌ Failed to connect to Nostr relay \(urlString): \(error?.localizedDescription ?? "Unknown error")", category: .session)
+                    self?.updateRelayStatus(urlString, isConnected: false, error: error)
+                    // Trigger disconnection handler for proper backoff
+                    self?.handleDisconnection(relayUrl: urlString, error: error ?? NSError(domain: "NostrRelay", code: -1, userInfo: nil))
+                }
+            }
+        }
+    }
+
+    /// Send any queued subscriptions for a relay that just connected.
+    private func flushPendingSubscriptions(for relayUrl: String) {
+        guard let map = pendingSubscriptions[relayUrl], !map.isEmpty else { return }
+        guard let connection = connections[relayUrl] else { return }
+        for (id, messageString) in map {
+            if self.subscriptions[relayUrl]?.contains(id) == true { continue }
+            connection.send(.string(messageString)) { error in
+                if let error = error {
+                    SecureLogger.error("❌ Failed to send pending subscription to \(relayUrl): \(error)", category: .session)
+                } else {
+                    Task { @MainActor in
+                        var subs = self.subscriptions[relayUrl] ?? Set<String>()
+                        subs.insert(id)
+                        self.subscriptions[relayUrl] = subs
+                    }
+                }
+            }
+        }
+        pendingSubscriptions[relayUrl] = nil
+    }
+    
+    private func receiveMessage(from task: URLSessionWebSocketTask, relayUrl: String) {
+        task.receive { [weak self] result in
+            guard let self = self else { return }
+            
+            switch result {
+            case .success(let message):
+                // Parse off-main to reduce UI jank, then hop back for state updates
+                Task.detached(priority: .utility) {
+                    guard let parsed = ParsedInbound(message) else { return }
+                    await MainActor.run {
+                        NostrRelayManager.shared.handleParsedMessage(parsed, from: relayUrl)
+                    }
+                }
+                
+                // Continue receiving
+                Task { @MainActor in
+                    self.receiveMessage(from: task, relayUrl: relayUrl)
+                }
+                
+            case .failure(let error):
+                DispatchQueue.main.async {
+                    self.handleDisconnection(relayUrl: relayUrl, error: error)
+                }
+            }
+        }
+    }
+    
+    // Parsed inbound message type (off-main)
+    // Note: declared at file scope below to avoid MainActor isolation inside this class
+    // and keep parsing off the main actor.
+
+    // Handle parsed message on MainActor (state updates and handlers)
+    private func handleParsedMessage(_ parsed: ParsedInbound, from relayUrl: String) {
+        switch parsed {
+        case .event(let subId, let event):
+            if event.kind != 1059 {
+                SecureLogger.debug("📥 Event kind=\(event.kind) id=\(event.id.prefix(16))… relay=\(relayUrl)", category: .session)
+            }
+            if let index = self.relays.firstIndex(where: { $0.url == relayUrl }) {
+                self.relays[index].messagesReceived += 1
+            }
+            if let handler = self.messageHandlers[subId] {
+                handler(event)
+            } else {
+                SecureLogger.warning("⚠️ No handler for subscription \(subId)", category: .session)
+            }
+        case .eose(let subId):
+            if var tracker = eoseTrackers[subId] {
+                tracker.pendingRelays.remove(relayUrl)
+                if tracker.pendingRelays.isEmpty {
+                    tracker.timer?.invalidate()
+                    eoseTrackers.removeValue(forKey: subId)
+                    tracker.callback()
+                } else {
+                    eoseTrackers[subId] = tracker
+                }
+            }
+        case .ok(let eventId, let success, let reason):
+            if success {
+                _ = Self.pendingGiftWrapIDs.remove(eventId)
+                SecureLogger.debug("✅ Accepted id=\(eventId.prefix(16))… relay=\(relayUrl)", category: .session)
+            } else {
+                let isGiftWrap = Self.pendingGiftWrapIDs.remove(eventId) != nil
+                if isGiftWrap {
+                    SecureLogger.warning("📮 Rejected id=\(eventId.prefix(16))… reason=\(reason)", category: .session)
+                } else {
+                    SecureLogger.error("📮 Rejected id=\(eventId.prefix(16))… reason=\(reason)", category: .session)
+                }
+            }
+        case .notice:
+            break
+        }
+    }
+    
+    private func sendToRelay(event: NostrEvent, connection: URLSessionWebSocketTask, relayUrl: String) {
+        let req = NostrRequest.event(event)
+        
+        do {
+            let data = try encoder.encode(req)
+            let message = String(data: data, encoding: .utf8) ?? ""
+            
+            SecureLogger.debug("📤 Send kind=\(event.kind) id=\(event.id.prefix(16))… relay=\(relayUrl)", category: .session)
+            
+            connection.send(.string(message)) { [weak self] error in
+                DispatchQueue.main.async {
+                    if let error = error {
+                        SecureLogger.error("❌ Failed to send event to \(relayUrl): \(error)", category: .session)
+                    } else {
+                        // SecureLogger.debug("✅ Event sent to relay: \(relayUrl)", category: .session)
+                        // Update relay stats
+                        if let index = self?.relays.firstIndex(where: { $0.url == relayUrl }) {
+                            self?.relays[index].messagesSent += 1
+                        }
+                    }
+                }
+            }
+        } catch {
+            SecureLogger.error("Failed to encode event: \(error)", category: .session)
+        }
+    }
+    
+    private func updateRelayStatus(_ url: String, isConnected: Bool, error: Error? = nil) {
+        if let index = relays.firstIndex(where: { $0.url == url }) {
+            relays[index].isConnected = isConnected
+            relays[index].lastError = error
+            if isConnected {
+                relays[index].lastConnectedAt = Date()
+                relays[index].reconnectAttempts = 0  // Reset on successful connection
+                relays[index].nextReconnectTime = nil
+            } else {
+                relays[index].lastDisconnectedAt = Date()
+            }
+        }
+        updateConnectionStatus()
+        // If we just connected to this relay, flush any queued sends targeting it
+        if isConnected {
+            flushMessageQueue(for: url)
+        }
+    }
+    
+    private func updateConnectionStatus() {
+        isConnected = relays.contains { $0.isConnected }
+    }
+    
+    private func handleDisconnection(relayUrl: String, error: Error) {
+        // If networking is disallowed, do not schedule reconnection
+        if !networkService.activationAllowed {
+            connections.removeValue(forKey: relayUrl)
+            subscriptions.removeValue(forKey: relayUrl)
+            updateRelayStatus(relayUrl, isConnected: false, error: error)
+            return
+        }
+        connections.removeValue(forKey: relayUrl)
+        subscriptions.removeValue(forKey: relayUrl)
+        updateRelayStatus(relayUrl, isConnected: false, error: error)
+        
+        // Check if this is a DNS or handshake error; treat as permanent
+        let errorDescription = error.localizedDescription.lowercased()
+        let ns = error as NSError
+        if errorDescription.contains("hostname could not be found") || 
+           errorDescription.contains("dns") ||
+           (ns.domain == NSURLErrorDomain && ns.code == NSURLErrorBadServerResponse) {
+            if relays.first(where: { $0.url == relayUrl })?.lastError == nil {
+                SecureLogger.warning("Nostr relay permanent failure for \(relayUrl) - not retrying (code=\(ns.code))", category: .session)
+            }
+            if let index = relays.firstIndex(where: { $0.url == relayUrl }) {
+                relays[index].lastError = error
+                relays[index].reconnectAttempts = maxReconnectAttempts
+                relays[index].nextReconnectTime = nil
+            }
+            pendingSubscriptions[relayUrl] = nil
+            return
+        }
+        
+        // Implement exponential backoff for non-DNS errors
+        guard let index = relays.firstIndex(where: { $0.url == relayUrl }) else { return }
+        
+        relays[index].reconnectAttempts += 1
+        
+        // Stop attempting after max attempts
+        if relays[index].reconnectAttempts >= maxReconnectAttempts {
+            SecureLogger.warning("Max reconnection attempts (\(maxReconnectAttempts)) reached for \(relayUrl)", category: .session)
+            return
+        }
+        
+        // Calculate backoff interval
+        let backoffInterval = min(
+            initialBackoffInterval * pow(backoffMultiplier, Double(relays[index].reconnectAttempts - 1)),
+            maxBackoffInterval
+        )
+        
+        let nextReconnectTime = Date().addingTimeInterval(backoffInterval)
+        relays[index].nextReconnectTime = nextReconnectTime
+        
+        
+        // Schedule reconnection with exponential backoff
+        let gen = connectionGeneration
+        DispatchQueue.main.asyncAfter(deadline: .now() + backoffInterval) { [weak self] in
+            guard let self = self else { return }
+            // Ignore stale scheduled reconnects from a previous generation
+            guard gen == self.connectionGeneration else { return }
+            // Check if we should still reconnect (relay might have been removed)
+            if self.relays.contains(where: { $0.url == relayUrl }) {
+                self.connectToRelay(relayUrl)
+            }
+        }
+    }
+    
+    // MARK: - Public Utility Methods
+    
+    /// Manually retry connection to a specific relay
+    func retryConnection(to relayUrl: String) {
+        guard let index = relays.firstIndex(where: { $0.url == relayUrl }) else { return }
+        
+        // Reset reconnection attempts
+        relays[index].reconnectAttempts = 0
+        relays[index].nextReconnectTime = nil
+        
+        // Disconnect if connected
+        if let connection = connections[relayUrl] {
+            connection.cancel(with: .goingAway, reason: nil)
+            connections.removeValue(forKey: relayUrl)
+        }
+        
+        // Attempt immediate reconnection
+        connectToRelay(relayUrl)
+    }
+    
+    /// Get detailed status for all relays
+    func getRelayStatuses() -> [(url: String, isConnected: Bool, reconnectAttempts: Int, nextReconnectTime: Date?)] {
+        return relays.map { relay in
+            (url: relay.url, 
+             isConnected: relay.isConnected, 
+             reconnectAttempts: relay.reconnectAttempts,
+             nextReconnectTime: relay.nextReconnectTime)
+        }
+    }
+    
+    /// Reset all relay connections
+    func resetAllConnections() {
+        disconnect()
+        // New generation begins now
+        connectionGeneration &+= 1
+        
+        // Reset all relay states
+        for index in relays.indices {
+            relays[index].reconnectAttempts = 0
+            relays[index].nextReconnectTime = nil
+            relays[index].lastError = nil
+        }
+        
+        // Reconnect
+        connect()
+    }
+
+    // MARK: - Failure classification
+    private func isPermanentlyFailed(_ url: String) -> Bool {
+        guard let r = relays.first(where: { $0.url == url }) else { return false }
+        if r.reconnectAttempts >= maxReconnectAttempts { return true }
+        if let ns = r.lastError as NSError?, ns.domain == NSURLErrorDomain {
+            if ns.code == NSURLErrorBadServerResponse || ns.code == NSURLErrorCannotFindHost {
+                return true
+            }
+        }
+        return false
+    }
+}
+
+// MARK: - Off-main inbound parsing helpers (file scope, non-isolated)
+
+private enum ParsedInbound {
+    case event(subId: String, event: NostrEvent)
+    case ok(eventId: String, success: Bool, reason: String)
+    case eose(subscriptionId: String)
+    case notice(String)
+    
+    init?(_ message: URLSessionWebSocketTask.Message) {
+        guard let data = message.data,
+              let array = try? JSONSerialization.jsonObject(with: data) as? [Any],
+              array.count >= 2,
+              let type = array[0] as? String else {
+            return nil
+        }
+
+        switch type {
+        case "EVENT":
+            if array.count >= 3,
+               let subId = array[1] as? String,
+               let eventDict = array[2] as? [String: Any],
+               let event = try? NostrEvent(from: eventDict) {
+                self = .event(subId: subId, event: event)
+                return
+            }
+            return nil
+        case "EOSE":
+            if let subId = array[1] as? String {
+                self = .eose(subscriptionId: subId)
+                return
+            }
+            return nil
+        case "OK":
+            if array.count >= 3,
+               let eventId = array[1] as? String,
+               let success = array[2] as? Bool {
+                let reason = array.count >= 4 ? (array[3] as? String ?? "no reason given") : "no reason given"
+                self = .ok(eventId: eventId, success: success, reason: reason)
+                return
+            }
+            return nil
+        case "NOTICE":
+            if array.count >= 2, let msg = array[1] as? String {
+                self = .notice(msg)
+                return
+            }
+            return nil
+        default:
+            return nil
+        }
+    }
+}
+
+private extension URLSessionWebSocketTask.Message {
+    var data: Data? {
+        switch self {
+        case .string(let text): text.data(using: .utf8)
+        case .data(let data):   data
+        @unknown default:       nil
+        }
+    }
+}
+
+// MARK: - Nostr Protocol Types
+
+enum NostrRequest: Encodable {
+    case event(NostrEvent)
+    case subscribe(id: String, filters: [NostrFilter])
+    case close(id: String)
+    
+    func encode(to encoder: Encoder) throws {
+        var container = encoder.unkeyedContainer()
+        
+        switch self {
+        case .event(let event):
+            try container.encode("EVENT")
+            try container.encode(event)
+            
+        case .subscribe(let id, let filters):
+            try container.encode("REQ")
+            try container.encode(id)
+            for filter in filters {
+                try container.encode(filter)
+            }
+            
+        case .close(let id):
+            try container.encode("CLOSE")
+            try container.encode(id)
+        }
+    }
+}
+
+struct NostrFilter: Encodable {
+    var ids: [String]?
+    var authors: [String]?
+    var kinds: [Int]?
+    var since: Int?
+    var until: Int?
+    var limit: Int?
+    
+    // Tag filters - stored internally but encoded specially
+    fileprivate var tagFilters: [String: [String]]?
+    
+    init() {
+        // Default initializer
+    }
+    
+    // Custom encoding to handle tag filters properly
+    enum CodingKeys: String, CodingKey {
+        case ids, authors, kinds, since, until, limit
+    }
+    
+    func encode(to encoder: Encoder) throws {
+        var container = encoder.container(keyedBy: DynamicCodingKey.self)
+        
+        // Encode standard fields
+        if let ids = ids { try container.encode(ids, forKey: DynamicCodingKey(stringValue: "ids")) }
+        if let authors = authors { try container.encode(authors, forKey: DynamicCodingKey(stringValue: "authors")) }
+        if let kinds = kinds { try container.encode(kinds, forKey: DynamicCodingKey(stringValue: "kinds")) }
+        if let since = since { try container.encode(since, forKey: DynamicCodingKey(stringValue: "since")) }
+        if let until = until { try container.encode(until, forKey: DynamicCodingKey(stringValue: "until")) }
+        if let limit = limit { try container.encode(limit, forKey: DynamicCodingKey(stringValue: "limit")) }
+        
+        // Encode tag filters with # prefix
+        if let tagFilters = tagFilters {
+            for (tag, values) in tagFilters {
+                try container.encode(values, forKey: DynamicCodingKey(stringValue: "#\(tag)"))
+            }
+        }
+    }
+    
+    // For NIP-17 gift wraps
+    static func giftWrapsFor(pubkey: String, since: Date? = nil) -> NostrFilter {
+        var filter = NostrFilter()
+        filter.kinds = [1059] // Gift wrap kind
+        filter.since = since?.timeIntervalSince1970.toInt()
+        filter.tagFilters = ["p": [pubkey]]
+        filter.limit = TransportConfig.nostrRelayDefaultFetchLimit // reasonable limit
+        return filter
+    }
+
+    // For location channels: geohash-scoped ephemeral events (kind 20000)
+    static func geohashEphemeral(_ geohash: String, since: Date? = nil, limit: Int = 200) -> NostrFilter {
+        var filter = NostrFilter()
+        filter.kinds = [20000]
+        filter.since = since?.timeIntervalSince1970.toInt()
+        filter.tagFilters = ["g": [geohash]]
+        filter.limit = limit
+        return filter
+    }
+
+    // For location notes: persistent text notes (kind 1) tagged with geohash
+    static func geohashNotes(_ geohash: String, since: Date? = nil, limit: Int = 200) -> NostrFilter {
+        var filter = NostrFilter()
+        filter.kinds = [1]
+        filter.since = since?.timeIntervalSince1970.toInt()
+        filter.tagFilters = ["g": [geohash]]
+        filter.limit = limit
+        return filter
+    }
+
+    // For location notes with neighbors: subscribe to multiple geohashes (center + neighbors)
+    static func geohashNotes(_ geohashes: [String], since: Date? = nil, limit: Int = 200) -> NostrFilter {
+        var filter = NostrFilter()
+        filter.kinds = [1]
+        filter.since = since?.timeIntervalSince1970.toInt()
+        filter.tagFilters = ["g": geohashes]
+        filter.limit = limit
+        return filter
+    }
+}
+
+// Dynamic coding key for tag filters
+private struct DynamicCodingKey: CodingKey {
+    var stringValue: String
+    var intValue: Int? { nil }
+    
+    init(stringValue: String) {
+        self.stringValue = stringValue
+    }
+    
+    init?(intValue: Int) {
+        return nil
+    }
+}
+
+private extension TimeInterval {
+    func toInt() -> Int {
+        return Int(self)
+    }
+}

bitchat/Nostr/XChaCha20Poly1305Compat.swift

@@ -0,0 +1,116 @@
+import Foundation
+import CryptoKit
+
+/// Minimal XChaCha20-Poly1305 compatibility wrapper using CryptoKit's ChaChaPoly.
+/// Implements HChaCha20 to derive a subkey and reduces the 24-byte nonce to a 12-byte nonce
+/// as per XChaCha20 construction.
+enum XChaCha20Poly1305Compat {
+    struct SealBox {
+        let ciphertext: Data
+        let tag: Data
+    }
+
+    static func seal(plaintext: Data, key: Data, nonce24: Data, aad: Data? = nil) throws -> SealBox {
+        precondition(key.count == 32, "XChaCha20 key must be 32 bytes")
+        precondition(nonce24.count == 24, "XChaCha20 nonce must be 24 bytes")
+
+        let subkey = hchacha20(key: key, nonce16: nonce24.prefix(16))
+        let nonce12 = derive12ByteNonce(from24: nonce24)
+        let chachaKey = SymmetricKey(data: subkey)
+        let nonce = try ChaChaPoly.Nonce(data: nonce12)
+        let sealed = try ChaChaPoly.seal(plaintext, using: chachaKey, nonce: nonce, authenticating: aad ?? Data())
+        return SealBox(ciphertext: sealed.ciphertext, tag: sealed.tag)
+    }
+
+    static func open(ciphertext: Data, tag: Data, key: Data, nonce24: Data, aad: Data? = nil) throws -> Data {
+        precondition(key.count == 32, "XChaCha20 key must be 32 bytes")
+        precondition(nonce24.count == 24, "XChaCha20 nonce must be 24 bytes")
+
+        let subkey = hchacha20(key: key, nonce16: nonce24.prefix(16))
+        let nonce12 = derive12ByteNonce(from24: nonce24)
+        let chachaKey = SymmetricKey(data: subkey)
+        let box = try ChaChaPoly.SealedBox(nonce: ChaChaPoly.Nonce(data: nonce12), ciphertext: ciphertext, tag: tag)
+        return try ChaChaPoly.open(box, using: chachaKey, authenticating: aad ?? Data())
+    }
+
+    // MARK: - Internals
+
+    private static func derive12ByteNonce(from24 nonce24: Data) -> Data {
+        // XChaCha20-Poly1305: 12-byte nonce = 4 zero bytes || last 8 bytes of the 24-byte nonce
+        var out = Data(count: 12)
+        out.replaceSubrange(0..<4, with: [0, 0, 0, 0])
+        out.replaceSubrange(4..<12, with: nonce24.suffix(8))
+        return out
+    }
+
+    private static func hchacha20(key: Data, nonce16: Data) -> Data {
+        // HChaCha20 based on the original ChaCha20 core with a 16-byte nonce.
+        precondition(key.count == 32)
+        precondition(nonce16.count == 16)
+
+        // Constants "expand 32-byte k"
+        var state: [UInt32] = [
+            0x61707865, 0x3320646e, 0x79622d32, 0x6b206574,
+            // key (8 words)
+            key.loadLEWord(0), key.loadLEWord(4), key.loadLEWord(8), key.loadLEWord(12),
+            key.loadLEWord(16), key.loadLEWord(20), key.loadLEWord(24), key.loadLEWord(28),
+            // nonce (4 words)
+            nonce16.loadLEWord(0), nonce16.loadLEWord(4), nonce16.loadLEWord(8), nonce16.loadLEWord(12)
+        ]
+
+        // 20 rounds (10 double rounds)
+        for _ in 0..<10 {
+            // Column rounds
+            quarterRound(&state, 0, 4, 8, 12)
+            quarterRound(&state, 1, 5, 9, 13)
+            quarterRound(&state, 2, 6, 10, 14)
+            quarterRound(&state, 3, 7, 11, 15)
+            // Diagonal rounds
+            quarterRound(&state, 0, 5, 10, 15)
+            quarterRound(&state, 1, 6, 11, 12)
+            quarterRound(&state, 2, 7, 8, 13)
+            quarterRound(&state, 3, 4, 9, 14)
+        }
+
+        // Output subkey: state[0..3] and state[12..15]
+        var out = Data(count: 32)
+        out.storeLEWord(state[0], at: 0)
+        out.storeLEWord(state[1], at: 4)
+        out.storeLEWord(state[2], at: 8)
+        out.storeLEWord(state[3], at: 12)
+        out.storeLEWord(state[12], at: 16)
+        out.storeLEWord(state[13], at: 20)
+        out.storeLEWord(state[14], at: 24)
+        out.storeLEWord(state[15], at: 28)
+        return out
+    }
+
+    private static func quarterRound(_ s: inout [UInt32], _ a: Int, _ b: Int, _ c: Int, _ d: Int) {
+        s[a] = s[a] &+ s[b]; s[d] ^= s[a]; s[d] = (s[d] << 16) | (s[d] >> 16)
+        s[c] = s[c] &+ s[d]; s[b] ^= s[c]; s[b] = (s[b] << 12) | (s[b] >> 20)
+        s[a] = s[a] &+ s[b]; s[d] ^= s[a]; s[d] = (s[d] << 8)  | (s[d] >> 24)
+        s[c] = s[c] &+ s[d]; s[b] ^= s[c]; s[b] = (s[b] << 7)  | (s[b] >> 25)
+    }
+}
+
+private extension Data {
+    func loadLEWord(_ offset: Int) -> UInt32 {
+        let range = offset..<(offset+4)
+        let bytes = self[range]
+        return bytes.withUnsafeBytes { ptr -> UInt32 in
+            let b = ptr.bindMemory(to: UInt8.self)
+            return UInt32(b[0]) | (UInt32(b[1]) << 8) | (UInt32(b[2]) << 16) | (UInt32(b[3]) << 24)
+        }
+    }
+
+    mutating func storeLEWord(_ value: UInt32, at offset: Int) {
+        let bytes: [UInt8] = [
+            UInt8(value & 0xff),
+            UInt8((value >> 8) & 0xff),
+            UInt8((value >> 16) & 0xff),
+            UInt8((value >> 24) & 0xff)
+        ]
+        replaceSubrange(offset..<(offset+4), with: bytes)
+    }
+}
+

bitchat/Protocols/BinaryEncodingUtils.swift

@@ -6,6 +6,7 @@
 //
 
 import Foundation
+import CryptoKit
 
 // MARK: - Hex Encoding/Decoding
 
@@ -16,6 +17,11 @@ extension Data {
         }
         return self.map { String(format: "%02x", $0) }.joined()
     }
+
+    func sha256Hex() -> String {
+        let digest = SHA256.hash(data: self)
+        return digest.map { String(format: "%02x", $0) }.joined()
+    }
     
     init?(hexString: String) {
         let len = hexString.count / 2
@@ -40,23 +46,23 @@ extension Data {
 extension Data {
     // MARK: Writing
     
-    mutating func appendUInt8(_ value: UInt8) {
+    @inlinable mutating func appendUInt8(_ value: UInt8) {
         self.append(value)
     }
     
-    mutating func appendUInt16(_ value: UInt16) {
+    @inlinable mutating func appendUInt16(_ value: UInt16) {
         self.append(UInt8((value >> 8) & 0xFF))
         self.append(UInt8(value & 0xFF))
     }
     
-    mutating func appendUInt32(_ value: UInt32) {
+    @inlinable mutating func appendUInt32(_ value: UInt32) {
         self.append(UInt8((value >> 24) & 0xFF))
         self.append(UInt8((value >> 16) & 0xFF))
         self.append(UInt8((value >> 8) & 0xFF))
         self.append(UInt8(value & 0xFF))
     }
     
-    mutating func appendUInt64(_ value: UInt64) {
+    @inlinable mutating func appendUInt64(_ value: UInt64) {
         for i in (0..<8).reversed() {
             self.append(UInt8((value >> (i * 8)) & 0xFF))
         }
@@ -113,21 +119,21 @@ extension Data {
     
     // MARK: Reading
     
-    func readUInt8(at offset: inout Int) -> UInt8? {
+    @inlinable func readUInt8(at offset: inout Int) -> UInt8? {
         guard offset >= 0 && offset < self.count else { return nil }
         let value = self[offset]
         offset += 1
         return value
     }
     
-    func readUInt16(at offset: inout Int) -> UInt16? {
+    @inlinable func readUInt16(at offset: inout Int) -> UInt16? {
         guard offset + 2 <= self.count else { return nil }
         let value = UInt16(self[offset]) << 8 | UInt16(self[offset + 1])
         offset += 2
         return value
     }
     
-    func readUInt32(at offset: inout Int) -> UInt32? {
+    @inlinable func readUInt32(at offset: inout Int) -> UInt32? {
         guard offset + 4 <= self.count else { return nil }
         let value = UInt32(self[offset]) << 24 |
                    UInt32(self[offset + 1]) << 16 |
@@ -137,7 +143,7 @@ extension Data {
         return value
     }
     
-    func readUInt64(at offset: inout Int) -> UInt64? {
+    @inlinable func readUInt64(at offset: inout Int) -> UInt64? {
         guard offset + 8 <= self.count else { return nil }
         var value: UInt64 = 0
         for i in 0..<8 {
@@ -197,7 +203,7 @@ extension Data {
         offset += 16
         
         // Convert 16 bytes to UUID string format
-        let uuid = uuidData.map { String(format: "%02x", $0) }.joined()
+        let uuid = uuidData.hexEncodedString()
         
         // Insert hyphens at proper positions: 8-4-4-4-12
         var result = ""
@@ -220,21 +226,3 @@ extension Data {
         return data
     }
 }
-
-// MARK: - Binary Message Protocol
-
-protocol BinaryEncodable {
-    func toBinaryData() -> Data
-    static func fromBinaryData(_ data: Data) -> Self?
-}
-
-// MARK: - Message Type Registry
-
-enum BinaryMessageType: UInt8 {
-    case deliveryAck = 0x01
-    case readReceipt = 0x02
-    case versionHello = 0x07
-    case versionAck = 0x08
-    case noiseIdentityAnnouncement = 0x09
-    case noiseMessage = 0x0A
-}

bitchat/Protocols/BinaryProtocol.swift

@@ -6,7 +6,90 @@
 // For more information, see <https://unlicense.org>
 //
 
+///
+/// # BinaryProtocol
+///
+/// Low-level binary encoding and decoding for BitChat protocol messages.
+/// Optimized for Bluetooth LE's limited bandwidth and MTU constraints.
+///
+/// ## Overview
+/// BinaryProtocol implements an efficient binary wire format that minimizes
+/// overhead while maintaining extensibility. It handles:
+/// - Compact binary encoding with fixed headers
+/// - Optional field support via flags
+/// - Automatic compression for large payloads
+/// - Endianness handling for cross-platform compatibility
+///
+/// ## Wire Format
+/// ```
+/// Header (Fixed 14 bytes for v1, 16 bytes for v2):
+/// +--------+------+-----+-----------+-------+------------------+
+/// |Version | Type | TTL | Timestamp | Flags | PayloadLength    |
+/// |1 byte  |1 byte|1byte| 8 bytes   | 1 byte| 2 or 4 bytes     |
+/// +--------+------+-----+-----------+-------+------------------+
+///
+/// Variable sections:
+/// +----------+-------------+---------+------------+
+/// | SenderID | RecipientID | Payload | Signature  |
+/// | 8 bytes  | 8 bytes*    | Variable| 64 bytes*  |
+/// +----------+-------------+---------+------------+
+/// * Optional fields based on flags
+/// ```
+///
+/// ## Design Rationale
+/// The protocol is designed for:
+/// - **Efficiency**: Minimal overhead for small messages
+/// - **Flexibility**: Optional fields via flag bits
+/// - **Compatibility**: Network byte order (big-endian)
+/// - **Performance**: Zero-copy where possible
+///
+/// ## Compression Strategy
+/// - Automatic compression for payloads > 256 bytes
+/// - zlib compression for broad compatibility on Apple platforms
+/// - Original size stored for decompression
+/// - Flag bit indicates compressed payload
+///
+/// ## Flag Bits
+/// - Bit 0: Has recipient ID (directed message)
+/// - Bit 1: Has signature (authenticated message)
+/// - Bit 2: Is compressed (zlib compression applied)
+/// - Bits 3-7: Reserved for future use
+///
+/// ## Size Constraints
+/// - Maximum packet size: 65,535 bytes (16-bit length field)
+/// - Typical packet size: < 512 bytes (BLE MTU)
+/// - Minimum packet size: 21 bytes (header + sender ID)
+///
+/// ## Encoding Process
+/// 1. Construct header with fixed fields
+/// 2. Set appropriate flags
+/// 3. Compress payload if beneficial
+/// 4. Append variable-length fields
+/// 5. Calculate and append signature if needed
+///
+/// ## Decoding Process
+/// 1. Validate minimum packet size
+/// 2. Parse fixed header
+/// 3. Extract flags and determine field presence
+/// 4. Parse variable fields based on flags
+/// 5. Decompress payload if compressed
+/// 6. Verify signature if present
+///
+/// ## Error Handling
+/// - Graceful handling of malformed packets
+/// - Clear error messages for debugging
+/// - No crashes on invalid input
+/// - Logging of protocol violations
+///
+/// ## Performance Notes
+/// - Allocation-free for small messages
+/// - Streaming support for large payloads
+/// - Efficient bit manipulation
+/// - Platform-optimized byte swapping
+///
+
 import Foundation
+import BitLogger
 
 extension Data {
     func trimmingNullBytes() -> Data {
@@ -18,94 +101,124 @@ extension Data {
     }
 }
 
-// Binary Protocol Format:
-// Header (Fixed 13 bytes):
-// - Version: 1 byte
-// - Type: 1 byte  
-// - TTL: 1 byte
-// - Timestamp: 8 bytes (UInt64)
-// - Flags: 1 byte (bit 0: hasRecipient, bit 1: hasSignature)
-// - PayloadLength: 2 bytes (UInt16)
-//
-// Variable sections:
-// - SenderID: 8 bytes (fixed)
-// - RecipientID: 8 bytes (if hasRecipient flag set)
-// - Payload: Variable length
-// - Signature: 64 bytes (if hasSignature flag set)
-
+/// Implements binary encoding and decoding for BitChat protocol messages.
+/// Provides static methods for converting between BitchatPacket objects and
+/// their binary wire format representation.
+/// - Note: All multi-byte values use network byte order (big-endian)
 struct BinaryProtocol {
-    static let headerSize = 13
+    static let v1HeaderSize = 14
+    static let v2HeaderSize = 16
     static let senderIDSize = 8
     static let recipientIDSize = 8
     static let signatureSize = 64
+
+    // Field offsets within packet header
+    struct Offsets {
+        static let version = 0
+        static let type = 1
+        static let ttl = 2
+        static let timestamp = 3
+        static let flags = 11  // After version(1) + type(1) + ttl(1) + timestamp(8)
+    }
+
+    static func headerSize(for version: UInt8) -> Int? {
+        switch version {
+        case 1: return v1HeaderSize
+        case 2: return v2HeaderSize
+        default: return nil
+        }
+    }
+
+    private static func lengthFieldSize(for version: UInt8) -> Int {
+        return version == 2 ? 4 : 2
+    }
     
     struct Flags {
         static let hasRecipient: UInt8 = 0x01
         static let hasSignature: UInt8 = 0x02
         static let isCompressed: UInt8 = 0x04
+        static let hasRoute: UInt8 = 0x08
     }
     
     // Encode BitchatPacket to binary format
-    static func encode(_ packet: BitchatPacket) -> Data? {
-        var data = Data()
-        
-        
-        // Try to compress payload if beneficial
+    static func encode(_ packet: BitchatPacket, padding: Bool = true) -> Data? {
+        let version = packet.version
+        guard version == 1 || version == 2 else { return nil }
+
+        // Try to compress payload when beneficial, keeping original size for later decoding
         var payload = packet.payload
-        var originalPayloadSize: UInt16? = nil
         var isCompressed = false
-        
+        var originalPayloadSize: Int?
         if CompressionUtil.shouldCompress(payload) {
-            if let compressedPayload = CompressionUtil.compress(payload) {
-                // Store original size for decompression (2 bytes after payload)
-                originalPayloadSize = UInt16(payload.count)
+            // Only compress when we can represent the original length in the outbound frame
+            let maxRepresentable = version == 2 ? Int(UInt32.max) : Int(UInt16.max)
+            if payload.count <= maxRepresentable,
+               let compressedPayload = CompressionUtil.compress(payload) {
+                originalPayloadSize = payload.count
                 payload = compressedPayload
                 isCompressed = true
-                
-            } else {
             }
-        } else {
         }
-        
-        // Header
-        data.append(packet.version)
+
+        let lengthFieldBytes = lengthFieldSize(for: version)
+        let originalRoute = packet.route ?? []
+        if originalRoute.contains(where: { $0.isEmpty }) { return nil }
+        let sanitizedRoute: [Data] = originalRoute.map { hop in
+            if hop.count == senderIDSize { return hop }
+            if hop.count > senderIDSize { return Data(hop.prefix(senderIDSize)) }
+            var padded = hop
+            padded.append(Data(repeating: 0, count: senderIDSize - hop.count))
+            return padded
+        }
+        guard sanitizedRoute.count <= 255 else { return nil }
+
+        let hasRoute = !sanitizedRoute.isEmpty
+        let routeLength = hasRoute ? 1 + sanitizedRoute.count * senderIDSize : 0
+        let originalSizeFieldBytes = isCompressed ? lengthFieldBytes : 0
+        let payloadDataSize = routeLength + payload.count + originalSizeFieldBytes
+
+        if version == 1 && payloadDataSize > Int(UInt16.max) { return nil }
+        if version == 2 && payloadDataSize > Int(UInt32.max) { return nil }
+
+        guard let headerSize = headerSize(for: version) else { return nil }
+        let estimatedHeader = headerSize + senderIDSize + (packet.recipientID == nil ? 0 : recipientIDSize)
+        let estimatedPayload = payloadDataSize
+        let estimatedSignature = (packet.signature == nil ? 0 : signatureSize)
+        var data = Data()
+        data.reserveCapacity(estimatedHeader + estimatedPayload + estimatedSignature + 255)
+
+        data.append(version)
         data.append(packet.type)
         data.append(packet.ttl)
-        
-        // Timestamp (8 bytes, big-endian)
-        for i in (0..<8).reversed() {
-            data.append(UInt8((packet.timestamp >> (i * 8)) & 0xFF))
+
+        for shift in stride(from: 56, through: 0, by: -8) {
+            data.append(UInt8((packet.timestamp >> UInt64(shift)) & 0xFF))
         }
-        
-        // Flags
+
         var flags: UInt8 = 0
-        if packet.recipientID != nil {
-            flags |= Flags.hasRecipient
-        }
-        if packet.signature != nil {
-            flags |= Flags.hasSignature
-        }
-        if isCompressed {
-            flags |= Flags.isCompressed
-        }
+        if packet.recipientID != nil { flags |= Flags.hasRecipient }
+        if packet.signature != nil { flags |= Flags.hasSignature }
+        if isCompressed { flags |= Flags.isCompressed }
+        if hasRoute { flags |= Flags.hasRoute }
         data.append(flags)
-        
-        // Payload length (2 bytes, big-endian) - includes original size if compressed
-        let payloadDataSize = payload.count + (isCompressed ? 2 : 0)
-        let payloadLength = UInt16(payloadDataSize)
-        
-        
-        data.append(UInt8((payloadLength >> 8) & 0xFF))
-        data.append(UInt8(payloadLength & 0xFF))
-        
-        // SenderID (exactly 8 bytes)
+
+        if version == 2 {
+            let length = UInt32(payloadDataSize)
+            for shift in stride(from: 24, through: 0, by: -8) {
+                data.append(UInt8((length >> UInt32(shift)) & 0xFF))
+            }
+        } else {
+            let length = UInt16(payloadDataSize)
+            data.append(UInt8((length >> 8) & 0xFF))
+            data.append(UInt8(length & 0xFF))
+        }
+
         let senderBytes = packet.senderID.prefix(senderIDSize)
         data.append(senderBytes)
         if senderBytes.count < senderIDSize {
             data.append(Data(repeating: 0, count: senderIDSize - senderBytes.count))
         }
-        
-        // RecipientID (if present)
+
         if let recipientID = packet.recipientID {
             let recipientBytes = recipientID.prefix(recipientIDSize)
             data.append(recipientBytes)
@@ -113,367 +226,193 @@ struct BinaryProtocol {
                 data.append(Data(repeating: 0, count: recipientIDSize - recipientBytes.count))
             }
         }
-        
-        // Payload (with original size prepended if compressed)
+
+        if hasRoute {
+            data.append(UInt8(sanitizedRoute.count))
+            for hop in sanitizedRoute {
+                data.append(hop)
+            }
+        }
+
         if isCompressed, let originalSize = originalPayloadSize {
-            // Prepend original size (2 bytes, big-endian)
-            data.append(UInt8((originalSize >> 8) & 0xFF))
-            data.append(UInt8(originalSize & 0xFF))
+            if version == 2 {
+                let value = UInt32(originalSize)
+                for shift in stride(from: 24, through: 0, by: -8) {
+                    data.append(UInt8((value >> UInt32(shift)) & 0xFF))
+                }
+            } else {
+                let value = UInt16(originalSize)
+                data.append(UInt8((value >> 8) & 0xFF))
+                data.append(UInt8(value & 0xFF))
+            }
         }
         data.append(payload)
-        
-        // Signature (if present)
+
         if let signature = packet.signature {
             data.append(signature.prefix(signatureSize))
         }
-        
-        
-        // Apply padding to standard block sizes for traffic analysis resistance
-        let optimalSize = MessagePadding.optimalBlockSize(for: data.count)
-        let paddedData = MessagePadding.pad(data, toSize: optimalSize)
-        
-        
-        return paddedData
+
+        if padding {
+            let optimalSize = MessagePadding.optimalBlockSize(for: data.count)
+            return MessagePadding.pad(data, toSize: optimalSize)
+        }
+        return data
     }
     
     // Decode binary data to BitchatPacket
     static func decode(_ data: Data) -> BitchatPacket? {
-        // Remove padding first
-        let unpaddedData = MessagePadding.unpad(data)
-        
-        
-        guard unpaddedData.count >= headerSize + senderIDSize else { 
-            return nil 
-        }
-        
-        var offset = 0
-        
-        // Header
-        let version = unpaddedData[offset]; offset += 1
-        // Check if version is supported
-        guard ProtocolVersion.isSupported(version) else { 
-            // Log unsupported version for debugging
-            return nil 
-        }
-        let type = unpaddedData[offset]; offset += 1
-        let ttl = unpaddedData[offset]; offset += 1
-        
-        // Timestamp
-        let timestampData = unpaddedData[offset..<offset+8]
-        let timestamp = timestampData.reduce(0) { result, byte in
-            (result << 8) | UInt64(byte)
-        }
-        offset += 8
-        
-        // Flags
-        let flags = unpaddedData[offset]; offset += 1
-        let hasRecipient = (flags & Flags.hasRecipient) != 0
-        let hasSignature = (flags & Flags.hasSignature) != 0
-        let isCompressed = (flags & Flags.isCompressed) != 0
-        
-        // Payload length
-        let payloadLengthData = unpaddedData[offset..<offset+2]
-        let payloadLength = payloadLengthData.reduce(0) { result, byte in
-            (result << 8) | UInt16(byte)
-        }
-        offset += 2
-        
-        // Calculate expected total size
-        var expectedSize = headerSize + senderIDSize + Int(payloadLength)
-        if hasRecipient {
-            expectedSize += recipientIDSize
-        }
-        if hasSignature {
-            expectedSize += signatureSize
-        }
-        
-        guard unpaddedData.count >= expectedSize else { 
-            return nil 
-        }
-        
-        // SenderID
-        let senderID = unpaddedData[offset..<offset+senderIDSize]
-        offset += senderIDSize
-        
-        // RecipientID
-        var recipientID: Data?
-        if hasRecipient {
-            recipientID = unpaddedData[offset..<offset+recipientIDSize]
-            offset += recipientIDSize
-        }
-        
-        // Payload
-        let payload: Data
-        if isCompressed {
-            // First 2 bytes are original size
-            guard Int(payloadLength) >= 2 else { return nil }
-            let originalSizeData = unpaddedData[offset..<offset+2]
-            let originalSize = Int(originalSizeData.reduce(0) { result, byte in
-                (result << 8) | UInt16(byte)
-            })
-            offset += 2
-            
-            // Compressed payload
-            let compressedPayload = unpaddedData[offset..<offset+Int(payloadLength)-2]
-            offset += Int(payloadLength) - 2
-            
-            // Decompress
-            guard let decompressedPayload = CompressionUtil.decompress(compressedPayload, originalSize: originalSize) else {
-                return nil
-            }
-            payload = decompressedPayload
-        } else {
-            payload = unpaddedData[offset..<offset+Int(payloadLength)]
-            offset += Int(payloadLength)
-        }
-        
-        // Signature
-        var signature: Data?
-        if hasSignature {
-            signature = unpaddedData[offset..<offset+signatureSize]
-        }
-        
-        return BitchatPacket(
-            type: type,
-            senderID: senderID,
-            recipientID: recipientID,
-            timestamp: timestamp,
-            payload: payload,
-            signature: signature,
-            ttl: ttl
-        )
+        // Try decode as-is first (robust when padding wasn't applied)
+        if let pkt = decodeCore(data) { return pkt }
+        // If that fails, try after removing padding
+        let unpadded = MessagePadding.unpad(data)
+        if unpadded as NSData === data as NSData { return nil }
+        return decodeCore(unpadded)
     }
-}
 
-// Binary encoding for BitchatMessage
-extension BitchatMessage {
-    func toBinaryPayload() -> Data? {
-        var data = Data()
-        
-        // Message format:
-        // - Flags: 1 byte (bit 0: isRelay, bit 1: isPrivate, bit 2: hasOriginalSender, bit 3: hasRecipientNickname, bit 4: hasSenderPeerID, bit 5: hasMentions)
-        // - Timestamp: 8 bytes (seconds since epoch)
-        // - ID length: 1 byte
-        // - ID: variable
-        // - Sender length: 1 byte
-        // - Sender: variable
-        // - Content length: 2 bytes
-        // - Content: variable
-        // Optional fields based on flags:
-        // - Original sender length + data
-        // - Recipient nickname length + data
-        // - Sender peer ID length + data
-        // - Mentions array
-        
-        var flags: UInt8 = 0
-        if isRelay { flags |= 0x01 }
-        if isPrivate { flags |= 0x02 }
-        if originalSender != nil { flags |= 0x04 }
-        if recipientNickname != nil { flags |= 0x08 }
-        if senderPeerID != nil { flags |= 0x10 }
-        if mentions != nil && !mentions!.isEmpty { flags |= 0x20 }
-        
-        data.append(flags)
-        
-        // Timestamp (in milliseconds)
-        let timestampMillis = UInt64(timestamp.timeIntervalSince1970 * 1000)
-        // Encode as 8 bytes, big-endian
-        for i in (0..<8).reversed() {
-            data.append(UInt8((timestampMillis >> (i * 8)) & 0xFF))
-        }
-        
-        // ID
-        if let idData = id.data(using: .utf8) {
-            data.append(UInt8(min(idData.count, 255)))
-            data.append(idData.prefix(255))
-        } else {
-            data.append(0)
-        }
-        
-        // Sender
-        if let senderData = sender.data(using: .utf8) {
-            data.append(UInt8(min(senderData.count, 255)))
-            data.append(senderData.prefix(255))
-        } else {
-            data.append(0)
-        }
-        
-        // Content
-        if let contentData = content.data(using: .utf8) {
-            let length = UInt16(min(contentData.count, 65535))
-            // Encode length as 2 bytes, big-endian
-            data.append(UInt8((length >> 8) & 0xFF))
-            data.append(UInt8(length & 0xFF))
-            data.append(contentData.prefix(Int(length)))
-        } else {
-            data.append(contentsOf: [0, 0])
-        }
-        
-        // Optional fields
-        if let originalSender = originalSender, let origData = originalSender.data(using: .utf8) {
-            data.append(UInt8(min(origData.count, 255)))
-            data.append(origData.prefix(255))
-        }
-        
-        if let recipientNickname = recipientNickname, let recipData = recipientNickname.data(using: .utf8) {
-            data.append(UInt8(min(recipData.count, 255)))
-            data.append(recipData.prefix(255))
-        }
-        
-        if let senderPeerID = senderPeerID, let peerData = senderPeerID.data(using: .utf8) {
-            data.append(UInt8(min(peerData.count, 255)))
-            data.append(peerData.prefix(255))
-        }
-        
-        // Mentions array
-        if let mentions = mentions {
-            data.append(UInt8(min(mentions.count, 255))) // Number of mentions
-            for mention in mentions.prefix(255) {
-                if let mentionData = mention.data(using: .utf8) {
-                    data.append(UInt8(min(mentionData.count, 255)))
-                    data.append(mentionData.prefix(255))
-                } else {
-                    data.append(0)
-                }
+    // Core decoding implementation used by decode(_:) with and without padding removal
+    private static func decodeCore(_ raw: Data) -> BitchatPacket? {
+        guard raw.count >= v1HeaderSize + senderIDSize else { return nil }
+
+        return raw.withUnsafeBytes { (buf: UnsafeRawBufferPointer) -> BitchatPacket? in
+            guard let base = buf.baseAddress else { return nil }
+            var offset = 0
+            func require(_ n: Int) -> Bool { offset + n <= buf.count }
+            func read8() -> UInt8? {
+                guard require(1) else { return nil }
+                let value = base.advanced(by: offset).assumingMemoryBound(to: UInt8.self).pointee
+                offset += 1
+                return value
             }
-        }
-        
-        
-        return data
-    }
-    
-    static func fromBinaryPayload(_ data: Data) -> BitchatMessage? {
-        // Create an immutable copy to prevent threading issues
-        let dataCopy = Data(data)
-        
-        
-        guard dataCopy.count >= 13 else { 
-            return nil 
-        }
-        
-        var offset = 0
-        
-        // Flags
-        guard offset < dataCopy.count else { 
-            return nil 
-        }
-        let flags = dataCopy[offset]; offset += 1
-        let isRelay = (flags & 0x01) != 0
-        let isPrivate = (flags & 0x02) != 0
-        let hasOriginalSender = (flags & 0x04) != 0
-        let hasRecipientNickname = (flags & 0x08) != 0
-        let hasSenderPeerID = (flags & 0x10) != 0
-        let hasMentions = (flags & 0x20) != 0
-        
-        // Timestamp
-        guard offset + 8 <= dataCopy.count else { 
-            return nil 
-        }
-        let timestampData = dataCopy[offset..<offset+8]
-        let timestampMillis = timestampData.reduce(0) { result, byte in
-            (result << 8) | UInt64(byte)
-        }
-        offset += 8
-        let timestamp = Date(timeIntervalSince1970: TimeInterval(timestampMillis) / 1000.0)
-        
-        // ID
-        guard offset < dataCopy.count else { 
-            return nil 
-        }
-        let idLength = Int(dataCopy[offset]); offset += 1
-        guard offset + idLength <= dataCopy.count else { 
-            return nil 
-        }
-        let id = String(data: dataCopy[offset..<offset+idLength], encoding: .utf8) ?? UUID().uuidString
-        offset += idLength
-        
-        // Sender
-        guard offset < dataCopy.count else { 
-            return nil 
-        }
-        let senderLength = Int(dataCopy[offset]); offset += 1
-        guard offset + senderLength <= dataCopy.count else { 
-            return nil 
-        }
-        let sender = String(data: dataCopy[offset..<offset+senderLength], encoding: .utf8) ?? "unknown"
-        offset += senderLength
-        
-        // Content
-        guard offset + 2 <= dataCopy.count else { 
-            return nil 
-        }
-        let contentLengthData = dataCopy[offset..<offset+2]
-        let contentLength = Int(contentLengthData.reduce(0) { result, byte in
-            (result << 8) | UInt16(byte)
-        })
-        offset += 2
-        guard offset + contentLength <= dataCopy.count else { 
-            return nil 
-        }
-        
-        let content = String(data: dataCopy[offset..<offset+contentLength], encoding: .utf8) ?? ""
-        offset += contentLength
-        
-        // Optional fields
-        var originalSender: String?
-        if hasOriginalSender && offset < dataCopy.count {
-            let length = Int(dataCopy[offset]); offset += 1
-            if offset + length <= dataCopy.count {
-                originalSender = String(data: dataCopy[offset..<offset+length], encoding: .utf8)
-                offset += length
+            func read16() -> UInt16? {
+                guard require(2) else { return nil }
+                let ptr = base.advanced(by: offset).assumingMemoryBound(to: UInt8.self)
+                let value = (UInt16(ptr[0]) << 8) | UInt16(ptr[1])
+                offset += 2
+                return value
             }
-        }
-        
-        var recipientNickname: String?
-        if hasRecipientNickname && offset < dataCopy.count {
-            let length = Int(dataCopy[offset]); offset += 1
-            if offset + length <= dataCopy.count {
-                recipientNickname = String(data: dataCopy[offset..<offset+length], encoding: .utf8)
-                offset += length
+            func read32() -> UInt32? {
+                guard require(4) else { return nil }
+                let ptr = base.advanced(by: offset).assumingMemoryBound(to: UInt8.self)
+                let value = (UInt32(ptr[0]) << 24) | (UInt32(ptr[1]) << 16) | (UInt32(ptr[2]) << 8) | UInt32(ptr[3])
+                offset += 4
+                return value
             }
-        }
-        
-        var senderPeerID: String?
-        if hasSenderPeerID && offset < dataCopy.count {
-            let length = Int(dataCopy[offset]); offset += 1
-            if offset + length <= dataCopy.count {
-                senderPeerID = String(data: dataCopy[offset..<offset+length], encoding: .utf8)
-                offset += length
+            func readData(_ n: Int) -> Data? {
+                guard require(n) else { return nil }
+                let ptr = base.advanced(by: offset)
+                let data = Data(bytes: ptr, count: n)
+                offset += n
+                return data
             }
-        }
-        
-        // Mentions array
-        var mentions: [String]?
-        if hasMentions && offset < dataCopy.count {
-            let mentionCount = Int(dataCopy[offset]); offset += 1
-            if mentionCount > 0 {
-                mentions = []
-                for _ in 0..<mentionCount {
-                    if offset < dataCopy.count {
-                        let length = Int(dataCopy[offset]); offset += 1
-                        if offset + length <= dataCopy.count {
-                            if let mention = String(data: dataCopy[offset..<offset+length], encoding: .utf8) {
-                                mentions?.append(mention)
-                            }
-                            offset += length
-                        }
+
+            guard let version = read8(), version == 1 || version == 2 else { return nil }
+            let lengthFieldBytes = lengthFieldSize(for: version)
+            guard let headerSize = headerSize(for: version) else { return nil }
+            let minimumRequired = headerSize + senderIDSize
+            guard raw.count >= minimumRequired else { return nil }
+
+            guard let type = read8(), let ttl = read8() else { return nil }
+
+            var timestamp: UInt64 = 0
+            for _ in 0..<8 {
+                guard let byte = read8() else { return nil }
+                timestamp = (timestamp << 8) | UInt64(byte)
+            }
+
+            guard let flags = read8() else { return nil }
+            let hasRecipient = (flags & Flags.hasRecipient) != 0
+            let hasSignature = (flags & Flags.hasSignature) != 0
+            let isCompressed = (flags & Flags.isCompressed) != 0
+
+            let payloadLength: Int
+            if version == 2 {
+                guard let len = read32() else { return nil }
+                payloadLength = Int(len)
+            } else {
+                guard let len = read16() else { return nil }
+                payloadLength = Int(len)
+            }
+
+            guard payloadLength >= 0 else { return nil }
+
+            guard let senderID = readData(senderIDSize) else { return nil }
+
+            var recipientID: Data? = nil
+            if hasRecipient {
+                recipientID = readData(recipientIDSize)
+                if recipientID == nil { return nil }
+            }
+
+            var route: [Data]? = nil
+            var remainingPayloadBytes = payloadLength
+
+            if (flags & Flags.hasRoute) != 0 {
+                guard remainingPayloadBytes >= 1, let routeCount = read8() else { return nil }
+                remainingPayloadBytes -= 1
+                if routeCount > 0 {
+                    var hops: [Data] = []
+                    for _ in 0..<Int(routeCount) {
+                        guard remainingPayloadBytes >= senderIDSize,
+                              let hop = readData(senderIDSize) else { return nil }
+                        remainingPayloadBytes -= senderIDSize
+                        hops.append(hop)
                     }
+                    route = hops
                 }
             }
+
+            let payload: Data
+            if isCompressed {
+                guard remainingPayloadBytes >= lengthFieldBytes else { return nil }
+                let originalSize: Int
+                if version == 2 {
+                    guard let rawSize = read32() else { return nil }
+                    originalSize = Int(rawSize)
+                } else {
+                    guard let rawSize = read16() else { return nil }
+                    originalSize = Int(rawSize)
+                }
+                remainingPayloadBytes -= lengthFieldBytes
+                guard originalSize >= 0 && originalSize <= FileTransferLimits.maxFramedFileBytes else { return nil }
+                let compressedSize = remainingPayloadBytes
+                guard compressedSize > 0, let compressed = readData(compressedSize) else { return nil }
+                remainingPayloadBytes = 0
+
+                let compressionRatio = Double(originalSize) / Double(compressedSize)
+                guard compressionRatio <= 50_000.0 else {
+                    SecureLogger.warning("🚫 Suspicious compression ratio: \(String(format: "%.0f", compressionRatio)):1", category: .security)
+                    return nil
+                }
+
+                guard let decompressed = CompressionUtil.decompress(compressed, originalSize: originalSize),
+                      decompressed.count == originalSize else { return nil }
+                payload = decompressed
+            } else {
+                guard remainingPayloadBytes >= 0,
+                      let rawPayload = readData(remainingPayloadBytes) else { return nil }
+                remainingPayloadBytes = 0
+                payload = rawPayload
+            }
+
+            var signature: Data? = nil
+            if hasSignature {
+                signature = readData(signatureSize)
+                if signature == nil { return nil }
+            }
+
+            guard offset <= buf.count else { return nil }
+
+            return BitchatPacket(
+                type: type,
+                senderID: senderID,
+                recipientID: recipientID,
+                timestamp: timestamp,
+                payload: payload,
+                signature: signature,
+                ttl: ttl,
+                version: version,
+                route: route
+            )
         }
-        
-        let message = BitchatMessage(
-            id: id,
-            sender: sender,
-            content: content,
-            timestamp: timestamp,
-            isRelay: isRelay,
-            originalSender: originalSender,
-            isPrivate: isPrivate,
-            recipientNickname: recipientNickname,
-            senderPeerID: senderPeerID,
-            mentions: mentions
-        )
-        return message
     }
 }

bitchat/Protocols/BitchatFilePacket.swift

@@ -0,0 +1,155 @@
+//
+// BitchatFilePacket.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+import BitLogger
+
+/// TLV payload for Bluetooth mesh file transfers (voice notes, images, generic files).
+/// Mirrors the Android client specification to ensure cross-platform interoperability.
+struct BitchatFilePacket {
+    var fileName: String?
+    var fileSize: UInt64?
+    var mimeType: String?
+    var content: Data
+
+    /// Canonical TLV tags defined by the Android implementation.
+    private enum TLVType: UInt8 {
+        case fileName = 0x01
+        case fileSize = 0x02
+        case mimeType = 0x03
+        case content = 0x04
+    }
+
+    /// Encodes the packet using v2 canonical TLVs (4-byte FILE_SIZE, 4-byte CONTENT length).
+    /// Returns `nil` when fields exceed protocol limits (e.g., content > UInt32.max).
+    func encode() -> Data? {
+        let resolvedSize = fileSize ?? UInt64(content.count)
+        guard resolvedSize <= UInt64(UInt32.max) else { return nil }
+        guard resolvedSize <= UInt64(FileTransferLimits.maxPayloadBytes) else { return nil }
+        guard content.count <= Int(UInt32.max) else { return nil }
+        guard FileTransferLimits.isValidPayload(content.count) else { return nil }
+
+        func appendBE<T: FixedWidthInteger>(_ value: T, into data: inout Data) {
+            var big = value.bigEndian
+            withUnsafeBytes(of: &big) { data.append(contentsOf: $0) }
+        }
+
+        var encoded = Data()
+
+        if let name = fileName, let nameData = name.data(using: .utf8), nameData.count <= Int(UInt16.max) {
+            encoded.append(TLVType.fileName.rawValue)
+            appendBE(UInt16(nameData.count), into: &encoded)
+            encoded.append(nameData)
+        }
+
+        encoded.append(TLVType.fileSize.rawValue)
+        appendBE(UInt16(4), into: &encoded)
+        appendBE(UInt32(resolvedSize), into: &encoded)
+
+        if let mime = mimeType, let mimeData = mime.data(using: .utf8), mimeData.count <= Int(UInt16.max) {
+            encoded.append(TLVType.mimeType.rawValue)
+            appendBE(UInt16(mimeData.count), into: &encoded)
+            encoded.append(mimeData)
+        }
+
+        encoded.append(TLVType.content.rawValue)
+        appendBE(UInt32(content.count), into: &encoded)
+        encoded.append(content)
+
+        return encoded
+    }
+
+    /// Decodes TLV payloads, tolerating legacy encodings (FILE_SIZE len=8, CONTENT len=2) when possible.
+    static func decode(_ data: Data) -> BitchatFilePacket? {
+        var cursor = data.startIndex
+        let end = data.endIndex
+
+        var fileName: String?
+        var fileSize: UInt64?
+        var mimeType: String?
+        var content = Data()
+
+        while cursor < end {
+            let typeRaw = data[cursor]
+            cursor = data.index(after: cursor)
+
+            guard cursor <= end else { return nil }
+            let tlvType = TLVType(rawValue: typeRaw)
+
+            func readBigEndianLength(bytes: Int) -> Int? {
+                guard data.distance(from: cursor, to: end) >= bytes else { return nil }
+                // Use UInt64 to prevent integer overflow during shift operations
+                var result: UInt64 = 0
+                for _ in 0..<bytes {
+                    result = (result << 8) | UInt64(data[cursor])
+                    cursor = data.index(after: cursor)
+                }
+                // Safely convert to Int with overflow check
+                guard result <= Int.max else { return nil }
+                return Int(result)
+            }
+
+            let length: Int?
+            if tlvType == .content {
+                let snapshot = cursor
+                let canonical = readBigEndianLength(bytes: 4)
+                if let canonical = canonical,
+                   canonical <= data.distance(from: cursor, to: end) {
+                    length = canonical
+                } else {
+                    cursor = snapshot
+                    length = readBigEndianLength(bytes: 2)
+                }
+            } else {
+                length = readBigEndianLength(bytes: 2)
+            }
+
+            guard let tlvLength = length, tlvLength >= 0 else { return nil }
+            guard data.distance(from: cursor, to: end) >= tlvLength else { return nil }
+
+            let valueStart = cursor
+            cursor = data.index(cursor, offsetBy: tlvLength)
+            let value = data[valueStart..<cursor]
+
+            switch tlvType {
+            case .fileName:
+                fileName = String(data: Data(value), encoding: .utf8)
+            case .fileSize:
+                if tlvLength == 4 || tlvLength == 8 {
+                    var size: UInt64 = 0
+                    for byte in value {
+                        size = (size << 8) | UInt64(byte)
+                    }
+                    if size > UInt64(FileTransferLimits.maxPayloadBytes) {
+                        return nil
+                    }
+                    fileSize = size
+                }
+            case .mimeType:
+                mimeType = String(data: Data(value), encoding: .utf8)
+            case .content:
+                let proposedSize = content.count + value.count
+                if proposedSize > FileTransferLimits.maxPayloadBytes {
+                    return nil
+                }
+                content.append(contentsOf: value)
+            case nil:
+                continue
+            }
+        }
+
+        guard !content.isEmpty else { return nil }
+        guard FileTransferLimits.isValidPayload(content.count) else { return nil }
+        return BitchatFilePacket(
+            fileName: fileName,
+            fileSize: fileSize ?? UInt64(content.count),
+            mimeType: mimeType,
+            content: content
+        )
+    }
+}

bitchat/Protocols/Geohash.swift

@@ -0,0 +1,175 @@
+import Foundation
+
+/// Lightweight Geohash encoder used for Location Channels.
+/// Encodes latitude/longitude to base32 geohash with a fixed precision.
+enum Geohash {
+    private static let base32Chars = Array("0123456789bcdefghjkmnpqrstuvwxyz")
+    private static let base32Map: [Character: Int] = {
+        var map: [Character: Int] = [:]
+        for (i, c) in base32Chars.enumerated() { map[c] = i }
+        return map
+    }()
+
+    /// Validates a geohash string for building-level precision (8 characters).
+    /// - Parameter geohash: The geohash string to validate
+    /// - Returns: true if valid 8-character base32 geohash, false otherwise
+    static func isValidBuildingGeohash(_ geohash: String) -> Bool {
+        guard geohash.count == 8 else { return false }
+        return geohash.lowercased().allSatisfy { base32Map[$0] != nil }
+    }
+
+    /// Encodes the provided coordinates into a geohash string.
+    /// - Parameters:
+    ///   - latitude: Latitude in degrees (-90...90)
+    ///   - longitude: Longitude in degrees (-180...180)
+    ///   - precision: Number of geohash characters (2-12 typical). Values <= 0 return an empty string.
+    /// - Returns: Base32 geohash string of length `precision`.
+    static func encode(latitude: Double, longitude: Double, precision: Int) -> String {
+        guard precision > 0 else { return "" }
+
+        var latInterval: (Double, Double) = (-90.0, 90.0)
+        var lonInterval: (Double, Double) = (-180.0, 180.0)
+
+        var isEven = true
+        var bit = 0
+        var ch = 0
+        var geohash: [Character] = []
+
+        let lat = max(-90.0, min(90.0, latitude))
+        let lon = max(-180.0, min(180.0, longitude))
+
+        while geohash.count < precision {
+            if isEven {
+                let mid = (lonInterval.0 + lonInterval.1) / 2
+                if lon >= mid {
+                    ch |= (1 << (4 - bit))
+                    lonInterval.0 = mid
+                } else {
+                    lonInterval.1 = mid
+                }
+            } else {
+                let mid = (latInterval.0 + latInterval.1) / 2
+                if lat >= mid {
+                    ch |= (1 << (4 - bit))
+                    latInterval.0 = mid
+                } else {
+                    latInterval.1 = mid
+                }
+            }
+
+            isEven.toggle()
+            if bit < 4 {
+                bit += 1
+            } else {
+                geohash.append(base32Chars[ch])
+                bit = 0
+                ch = 0
+            }
+        }
+
+        return String(geohash)
+    }
+
+    /// Decodes a geohash into the center latitude/longitude of its bounding box.
+    /// - Parameter geohash: Base32 geohash string.
+    /// - Returns: (lat, lon) center coordinate.
+    static func decodeCenter(_ geohash: String) -> (lat: Double, lon: Double) {
+        var latInterval: (Double, Double) = (-90.0, 90.0)
+        var lonInterval: (Double, Double) = (-180.0, 180.0)
+
+        var isEven = true
+        for ch in geohash.lowercased() {
+            guard let cd = base32Map[ch] else { continue }
+            for mask in [16, 8, 4, 2, 1] {
+                if isEven {
+                    let mid = (lonInterval.0 + lonInterval.1) / 2
+                    if (cd & mask) != 0 { lonInterval.0 = mid } else { lonInterval.1 = mid }
+                } else {
+                    let mid = (latInterval.0 + latInterval.1) / 2
+                    if (cd & mask) != 0 { latInterval.0 = mid } else { latInterval.1 = mid }
+                }
+                isEven.toggle()
+            }
+        }
+        let lat = (latInterval.0 + latInterval.1) / 2
+        let lon = (lonInterval.0 + lonInterval.1) / 2
+        return (lat, lon)
+    }
+
+    /// Decodes a geohash into its latitude and longitude bounds.
+    /// - Parameter geohash: Base32 geohash string.
+    /// - Returns: (latMin, latMax, lonMin, lonMax)
+    static func decodeBounds(_ geohash: String) -> (latMin: Double, latMax: Double, lonMin: Double, lonMax: Double) {
+        var latInterval: (Double, Double) = (-90.0, 90.0)
+        var lonInterval: (Double, Double) = (-180.0, 180.0)
+
+        var isEven = true
+        for ch in geohash.lowercased() {
+            guard let cd = base32Map[ch] else { continue }
+            for mask in [16, 8, 4, 2, 1] {
+                if isEven {
+                    let mid = (lonInterval.0 + lonInterval.1) / 2
+                    if (cd & mask) != 0 { lonInterval.0 = mid } else { lonInterval.1 = mid }
+                } else {
+                    let mid = (latInterval.0 + latInterval.1) / 2
+                    if (cd & mask) != 0 { latInterval.0 = mid } else { latInterval.1 = mid }
+                }
+                isEven.toggle()
+            }
+        }
+        return (latInterval.0, latInterval.1, lonInterval.0, lonInterval.1)
+    }
+
+    /// Returns all 8 neighboring geohash cells at the same precision.
+    /// - Parameter geohash: Base32 geohash string.
+    /// - Returns: Array of 8 neighboring geohashes (N, NE, E, SE, S, SW, W, NW order).
+    static func neighbors(of geohash: String) -> [String] {
+        guard !geohash.isEmpty else { return [] }
+
+        let precision = geohash.count
+        let bounds = decodeBounds(geohash)
+        let center = decodeCenter(geohash)
+
+        // Calculate cell dimensions
+        let latHeight = bounds.latMax - bounds.latMin
+        let lonWidth = bounds.lonMax - bounds.lonMin
+
+        // Helper to wrap longitude around ±180
+        func wrapLongitude(_ lon: Double) -> Double {
+            var wrapped = lon
+            while wrapped > 180.0 { wrapped -= 360.0 }
+            while wrapped < -180.0 { wrapped += 360.0 }
+            return wrapped
+        }
+
+        // Helper to clamp latitude to ±90
+        func clampLatitude(_ lat: Double) -> Double {
+            return max(-90.0, min(90.0, lat))
+        }
+
+        // Calculate 8 neighbor centers
+        let neighbors: [(lat: Double, lon: Double)] = [
+            (center.lat + latHeight, center.lon),                    // N
+            (center.lat + latHeight, center.lon + lonWidth),         // NE
+            (center.lat, center.lon + lonWidth),                     // E
+            (center.lat - latHeight, center.lon + lonWidth),         // SE
+            (center.lat - latHeight, center.lon),                    // S
+            (center.lat - latHeight, center.lon - lonWidth),         // SW
+            (center.lat, center.lon - lonWidth),                     // W
+            (center.lat + latHeight, center.lon - lonWidth)          // NW
+        ]
+
+        // Encode each neighbor, handling boundary conditions
+        return neighbors.compactMap { neighbor in
+            let lat = clampLatitude(neighbor.lat)
+            let lon = wrapLongitude(neighbor.lon)
+
+            // Skip if we've crossed a pole (latitude clamped to boundary)
+            if (neighbor.lat > 90.0 || neighbor.lat < -90.0) {
+                return nil
+            }
+
+            return encode(latitude: lat, longitude: lon, precision: precision)
+        }
+    }
+}

bitchat/Protocols/LocationChannel.swift

@@ -0,0 +1,133 @@
+import Foundation
+
+/// Levels of location channels mapped to geohash precisions.
+enum GeohashChannelLevel: CaseIterable, Codable, Equatable {
+    case building
+    case block
+    case neighborhood
+    case city
+    case province   // previously .region
+    case region     // previously .country
+
+    /// Geohash length used for this level.
+    var precision: Int {
+        switch self {
+        case .building: return 8
+        case .block: return 7
+        case .neighborhood: return 6
+        case .city: return 5
+        case .province: return 4
+        case .region: return 2
+    }
+    }
+
+    var displayName: String {
+        switch self {
+        case .building:
+            return String(localized: "location_levels.building", comment: "Name for building-level location channel")
+        case .block:
+            return String(localized: "location_levels.block", comment: "Name for block-level location channel")
+        case .neighborhood:
+            return String(localized: "location_levels.neighborhood", comment: "Name for neighborhood-level location channel")
+        case .city:
+            return String(localized: "location_levels.city", comment: "Name for city-level location channel")
+        case .province:
+            return String(localized: "location_levels.province", comment: "Name for province-level location channel")
+        case .region:
+            return String(localized: "location_levels.region", comment: "Name for region-level location channel")
+        }
+    }
+}
+// Backward-compatible Codable for renamed cases
+extension GeohashChannelLevel {
+    init(from decoder: Decoder) throws {
+        let container = try decoder.singleValueContainer()
+        if let raw = try? container.decode(String.self) {
+            switch raw {
+            case "building": self = .building
+            case "block": self = .block
+            case "neighborhood": self = .neighborhood
+            case "city": self = .city
+            case "region": self = .province      // old "region" maps to new .province
+            case "country": self = .region       // old "country" maps to new .region
+            case "province": self = .province
+            default:
+                self = .block
+            }
+        } else if let precision = try? container.decode(Int.self) {
+            switch precision {
+            case 8: self = .building
+            case 7: self = .block
+            case 6: self = .neighborhood
+            case 5: self = .city
+            case 4: self = .province
+            case 0...3: self = .region
+            default: self = .block
+            }
+        } else {
+            self = .block
+        }
+    }
+
+    func encode(to encoder: Encoder) throws {
+        var container = encoder.singleValueContainer()
+        switch self {
+        case .building: try container.encode("building")
+        case .block: try container.encode("block")
+        case .neighborhood: try container.encode("neighborhood")
+        case .city: try container.encode("city")
+        case .province: try container.encode("province")
+        case .region: try container.encode("region")
+        }
+    }
+}
+
+/// A computed geohash channel option.
+struct GeohashChannel: Codable, Equatable, Hashable, Identifiable {
+    let level: GeohashChannelLevel
+    let geohash: String
+
+    var id: String { "\(level)-\(geohash)" }
+
+    var displayName: String {
+        "\(level.displayName) • \(geohash)"
+    }
+}
+
+/// Identifier for current public chat channel (mesh or a location geohash).
+enum ChannelID: Equatable, Codable {
+    case mesh
+    case location(GeohashChannel)
+
+    /// Human readable name for UI.
+    var displayName: String {
+        switch self {
+        case .mesh:
+            return "Mesh"
+        case .location(let ch):
+            return ch.displayName
+        }
+    }
+
+    /// Nostr tag value for scoping (geohash), if applicable.
+    var nostrGeohashTag: String? {
+        switch self {
+        case .mesh: return nil
+        case .location(let ch): return ch.geohash
+        }
+    }
+    
+    var isMesh: Bool {
+        switch self {
+        case .mesh:     true
+        case .location: false
+        }
+    }
+    
+    var isLocation: Bool {
+        switch self {
+        case .mesh:     false
+        case .location: true
+        }
+    }
+}

bitchat/Protocols/Packets.swift

@@ -0,0 +1,162 @@
+import Foundation
+
+// MARK: - Protocol TLV Packets
+
+struct AnnouncementPacket {
+    let nickname: String
+    let noisePublicKey: Data            // Noise static public key (Curve25519.KeyAgreement)
+    let signingPublicKey: Data          // Ed25519 public key for signing
+    let directNeighbors: [Data]?        // 8-byte peer IDs
+
+    private enum TLVType: UInt8 {
+        case nickname = 0x01
+        case noisePublicKey = 0x02
+        case signingPublicKey = 0x03
+        case directNeighbors = 0x04
+    }
+
+    func encode() -> Data? {
+        var data = Data()
+        // Reserve: TLVs for nickname (2 + n), noise key (2 + 32), signing key (2 + 32)
+        data.reserveCapacity(2 + min(nickname.count, 255) + 2 + noisePublicKey.count + 2 + signingPublicKey.count)
+
+        // TLV for nickname
+        guard let nicknameData = nickname.data(using: .utf8), nicknameData.count <= 255 else { return nil }
+        data.append(TLVType.nickname.rawValue)
+        data.append(UInt8(nicknameData.count))
+        data.append(nicknameData)
+
+        // TLV for noise public key
+        guard noisePublicKey.count <= 255 else { return nil }
+        data.append(TLVType.noisePublicKey.rawValue)
+        data.append(UInt8(noisePublicKey.count))
+        data.append(noisePublicKey)
+
+        // TLV for signing public key
+        guard signingPublicKey.count <= 255 else { return nil }
+        data.append(TLVType.signingPublicKey.rawValue)
+        data.append(UInt8(signingPublicKey.count))
+        data.append(signingPublicKey)
+        
+        // TLV for direct neighbors (optional)
+        if let neighbors = directNeighbors, !neighbors.isEmpty {
+            let neighborsData = neighbors.prefix(10).reduce(Data()) { $0 + $1 }
+            if !neighborsData.isEmpty && neighborsData.count % 8 == 0 {
+                data.append(TLVType.directNeighbors.rawValue)
+                data.append(UInt8(neighborsData.count))
+                data.append(neighborsData)
+            }
+        }
+
+        return data
+    }
+
+    static func decode(from data: Data) -> AnnouncementPacket? {
+        var offset = 0
+        var nickname: String?
+        var noisePublicKey: Data?
+        var signingPublicKey: Data?
+        var directNeighbors: [Data]?
+
+        while offset + 2 <= data.count {
+            let typeRaw = data[offset]
+            offset += 1
+            let length = Int(data[offset])
+            offset += 1
+
+            guard offset + length <= data.count else { return nil }
+            let value = data[offset..<offset + length]
+            offset += length
+
+            if let type = TLVType(rawValue: typeRaw) {
+                switch type {
+                case .nickname:
+                    nickname = String(data: value, encoding: .utf8)
+                case .noisePublicKey:
+                    noisePublicKey = Data(value)
+                case .signingPublicKey:
+                    signingPublicKey = Data(value)
+                case .directNeighbors:
+                    if length > 0 && length % 8 == 0 {
+                        var neighbors = [Data]()
+                        let count = length / 8
+                        for i in 0..<count {
+                            let start = value.startIndex + i * 8
+                            let end = start + 8
+                            neighbors.append(Data(value[start..<end]))
+                        }
+                        directNeighbors = neighbors
+                    }
+                }
+            } else {
+                // Unknown TLV; skip (tolerant decoder for forward compatibility)
+                continue
+            }
+        }
+
+        guard let nickname = nickname, let noisePublicKey = noisePublicKey, let signingPublicKey = signingPublicKey else { return nil }
+        return AnnouncementPacket(
+            nickname: nickname,
+            noisePublicKey: noisePublicKey,
+            signingPublicKey: signingPublicKey,
+            directNeighbors: directNeighbors
+        )
+    }
+}
+
+struct PrivateMessagePacket {
+    let messageID: String
+    let content: String
+
+    private enum TLVType: UInt8 {
+        case messageID = 0x00
+        case content = 0x01
+    }
+
+    func encode() -> Data? {
+        var data = Data()
+        data.reserveCapacity(2 + min(messageID.count, 255) + 2 + min(content.count, 255))
+
+        // TLV for messageID
+        guard let messageIDData = messageID.data(using: .utf8), messageIDData.count <= 255 else { return nil }
+        data.append(TLVType.messageID.rawValue)
+        data.append(UInt8(messageIDData.count))
+        data.append(messageIDData)
+
+        // TLV for content
+        guard let contentData = content.data(using: .utf8), contentData.count <= 255 else { return nil }
+        data.append(TLVType.content.rawValue)
+        data.append(UInt8(contentData.count))
+        data.append(contentData)
+
+        return data
+    }
+
+    static func decode(from data: Data) -> PrivateMessagePacket? {
+        var offset = 0
+        var messageID: String?
+        var content: String?
+
+        while offset + 2 <= data.count {
+            guard let type = TLVType(rawValue: data[offset]) else { return nil }
+            offset += 1
+
+            let length = Int(data[offset])
+            offset += 1
+
+            guard offset + length <= data.count else { return nil }
+            let value = data[offset..<offset + length]
+            offset += length
+
+            switch type {
+            case .messageID:
+                messageID = String(data: value, encoding: .utf8)
+            case .content:
+                content = String(data: value, encoding: .utf8)
+            }
+        }
+
+        guard let messageID = messageID, let content = content else { return nil }
+        return PrivateMessagePacket(messageID: messageID, content: content)
+    }
+}

bitchat/Services/AutocompleteService.swift

@@ -0,0 +1,104 @@
+//
+// AutocompleteService.swift
+// bitchat
+//
+// Handles autocomplete suggestions for mentions and commands
+// This is free and unencumbered software released into the public domain.
+//
+
+import Foundation
+
+/// Manages autocomplete functionality for chat
+final class AutocompleteService {
+    private let mentionRegex = try? NSRegularExpression(pattern: "@([\\p{L}0-9_]*)$", options: [])
+    private let commandRegex = try? NSRegularExpression(pattern: "^/([a-z]*)$", options: [])
+    
+    private let commands = [
+        "/msg", "/who", "/clear",
+        "/hug", "/slap", "/fav", "/unfav",
+        "/block", "/unblock"
+    ]
+    
+    /// Get autocomplete suggestions for current text
+    func getSuggestions(for text: String, peers: [String], cursorPosition: Int) -> (suggestions: [String], range: NSRange?) {
+        let textToPosition = String(text.prefix(cursorPosition))
+        
+        // Check for mention autocomplete
+        if let (mentionSuggestions, mentionRange) = getMentionSuggestions(textToPosition, peers: peers) {
+            return (mentionSuggestions, mentionRange)
+        }
+        
+        // Don't handle command autocomplete here - ContentView handles it with better UI
+        // if let (commandSuggestions, commandRange) = getCommandSuggestions(textToPosition) {
+        //     return (commandSuggestions, commandRange)
+        // }
+        
+        return ([], nil)
+    }
+    
+    /// Apply selected suggestion to text
+    func applySuggestion(_ suggestion: String, to text: String, range: NSRange) -> String {
+        guard let textRange = Range(range, in: text) else { return text }
+        
+        var replacement = suggestion
+        
+        // Add space after command if it takes arguments
+        if suggestion.hasPrefix("/") && needsArgument(command: suggestion) {
+            replacement += " "
+        }
+        
+        return text.replacingCharacters(in: textRange, with: replacement)
+    }
+    
+    // MARK: - Private Methods
+    
+    private func getMentionSuggestions(_ text: String, peers: [String]) -> ([String], NSRange)? {
+        guard let regex = mentionRegex else { return nil }
+        
+        let nsText = text as NSString
+        let matches = regex.matches(in: text, options: [], range: NSRange(location: 0, length: nsText.length))
+        
+        guard let match = matches.last else { return nil }
+        
+        let fullRange = match.range(at: 0)
+        let captureRange = match.range(at: 1)
+        let prefix = nsText.substring(with: captureRange).lowercased()
+        
+        let suggestions = peers
+            .filter { $0.lowercased().hasPrefix(prefix) }
+            .sorted()
+            .prefix(5)
+            .map { "@\($0)" }
+        
+        return suggestions.isEmpty ? nil : (Array(suggestions), fullRange)
+    }
+    
+    private func getCommandSuggestions(_ text: String) -> ([String], NSRange)? {
+        guard let regex = commandRegex else { return nil }
+        
+        let nsText = text as NSString
+        let matches = regex.matches(in: text, options: [], range: NSRange(location: 0, length: nsText.length))
+        
+        guard let match = matches.last else { return nil }
+        
+        let fullRange = match.range(at: 0)
+        let captureRange = match.range(at: 1)
+        let prefix = nsText.substring(with: captureRange).lowercased()
+        
+        let suggestions = commands
+            .filter { $0.hasPrefix("/\(prefix)") }
+            .sorted()
+            .prefix(5)
+        
+        return suggestions.isEmpty ? nil : (Array(suggestions), fullRange)
+    }
+    
+    private func needsArgument(command: String) -> Bool {
+        switch command {
+        case "/who", "/clear":
+            return false
+        default:
+            return true
+        }
+    }
+}

bitchat/Services/BLE/MimeType.swift

@@ -0,0 +1,195 @@
+//
+// MimeType.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import UniformTypeIdentifiers
+
+// MARK: - Extensions for missing UTTypes
+
+extension UTType {
+    static let webP = UTType(importedAs: "image/webp")
+    static let aac  = UTType(importedAs: "audio/aac")
+    static let m4a  = UTType(importedAs: "audio/m4a")
+    static let ogg  = UTType(importedAs: "audio/ogg")
+}
+
+// MARK: - MimeType Enum
+
+enum MimeType: CaseIterable, Hashable {
+    case jpeg
+    case jpg
+    case png
+    case gif
+    case webp
+    case mp4Audio
+    case m4a
+    case aac
+    case mpeg
+    case mp3
+    case wav
+    case xWav
+    case ogg
+    case pdf
+    case octetStream
+
+    var utType: UTType {
+        switch self {
+        case .jpeg, .jpg:   .jpeg
+        case .png:          .png
+        case .gif:          .gif
+        case .webp:         .webP
+        case .aac:          .aac
+        case .m4a:          .m4a
+        case .mp4Audio:     .mpeg4Audio
+        case .mp3, .mpeg:   .mp3
+        case .wav, .xWav:   .wav
+        case .ogg:          .ogg
+        case .pdf:          .pdf
+        case .octetStream:  .data
+        }
+    }
+    
+    var category: Category {
+        switch self {
+        case .jpeg, .jpg, .png, .gif, .webp:
+            return .image
+        case .aac, .m4a, .mp4Audio, .mpeg, .mp3, .wav, .xWav, .ogg:
+            return .audio
+        case .pdf, .octetStream:
+            return .file
+        }
+    }
+
+
+    var mimeString: String {
+        switch self {
+        case .jpeg, .jpg:   "image/jpeg"
+        case .png:          "image/png"
+        case .gif:          "image/gif"
+        case .webp:         "image/webp"
+        case .mp4Audio:     "audio/mp4"
+        case .m4a:          "audio/m4a"
+        case .aac:          "audio/aac"
+        case .mpeg:         "audio/mpeg"
+        case .mp3:          "audio/mp3"
+        case .wav:          "audio/wav"
+        case .xWav:         "audio/x-wav"
+        case .ogg:          "audio/ogg"
+        case .pdf:          "application/pdf"
+        case .octetStream:  "application/octet-stream"
+        }
+    }
+    
+    var defaultExtension: String {
+        switch self {
+        case .jpeg, .jpg:           "jpg"
+        case .png:                  "png"
+        case .webp:                 "webp"
+        case .gif:                  "gif"
+        case .mp4Audio, .m4a, .aac: "m4a"
+        case .mpeg, .mp3:           "mp3"
+        case .wav, .xWav:           "wav"
+        case .ogg:                  "ogg"
+        case .pdf:                  "pdf"
+        case .octetStream:          "bin"
+        }
+    }
+
+    static var allowed: Set<MimeType> = [
+        .jpeg, .jpg, .png, .gif, .webp,
+        .mp4Audio, .m4a, .aac, .mpeg, .mp3,
+        .wav, .xWav, .ogg,
+        .pdf, .octetStream
+    ]
+
+    var isAllowed: Bool {
+        Self.allowed.contains(self)
+    }
+
+    // MARK: - Byte signature validation
+    func matches(data: Data) -> Bool {
+        guard !data.isEmpty else { return false }
+
+        // Generic type → skip validation
+        if self == .octetStream { return true }
+
+        switch self {
+        case .jpeg, .jpg:
+            return data.count >= 3 && data[0] == 0xFF && data[1] == 0xD8 && data[2] == 0xFF
+
+        case .png:
+            return data.count >= 8 &&
+                   data[0] == 0x89 && data[1] == 0x50 && data[2] == 0x4E && data[3] == 0x47 &&
+                   data[4] == 0x0D && data[5] == 0x0A && data[6] == 0x1A && data[7] == 0x0A
+
+        case .gif:
+            return data.count >= 6 && data[0] == 0x47 && data[1] == 0x49 && data[2] == 0x46 &&
+                   data[3] == 0x38 && (data[4] == 0x37 || data[4] == 0x39) && data[5] == 0x61
+
+        case .webp:
+            return data.count >= 12 &&
+                   data[0] == 0x52 && data[1] == 0x49 && data[2] == 0x46 && data[3] == 0x46 &&
+                   data[8] == 0x57 && data[9] == 0x45 && data[10] == 0x42 && data[11] == 0x50
+
+        case .m4a, .mp4Audio, .aac:
+            // AVAudioRecorder output varies by platform - be lenient
+            // Security: size already capped + sandboxed execution
+            return data.count > 100
+
+        case .mpeg, .mp3:
+            if data.count >= 3 && data[0] == 0x49 && data[1] == 0x44 && data[2] == 0x33 {
+                return true // ID3 header
+            }
+            return data.count >= 2 && data[0] == 0xFF && (data[1] & 0xE0) == 0xE0
+
+        case .wav, .xWav:
+            return data.count >= 12 &&
+                   data[0] == 0x52 && data[1] == 0x49 && data[2] == 0x46 && data[3] == 0x46 &&
+                   data[8] == 0x57 && data[9] == 0x41 && data[10] == 0x56 && data[11] == 0x45
+
+        case .ogg:
+            return data.count >= 4 &&
+                   data[0] == 0x4F && data[1] == 0x67 && data[2] == 0x67 && data[3] == 0x53
+
+        case .pdf:
+            return data.count >= 4 &&
+                   data[0] == 0x25 && data[1] == 0x50 && data[2] == 0x44 && data[3] == 0x46
+
+        default:
+            return false
+        }
+    }
+
+    // MARK: - Convenience Initializers
+
+    init?(_ mimeString: String?) {
+        guard let mimeString else { return nil }
+        
+        let normalized = mimeString.lowercased()
+
+        // Direct match with our canonical list
+        if let match = MimeType.allCases.first(where: { $0.mimeString == normalized }) {
+            self = match
+            return
+        }
+
+        // Let UTType normalize aliases like "image/jpg", "audio/x-wav", etc.
+        if let type = UTType(mimeType: normalized),
+           let match = MimeType.allCases.first(where: { type.conforms(to: $0.utType) }) {
+            self = match
+            return
+        }
+
+        return nil
+    }
+}
+
+extension MimeType {
+    enum Category: String {
+        case audio, image, file
+    }
+}

bitchat/Services/CommandProcessor.swift

@@ -0,0 +1,311 @@
+//
+// CommandProcessor.swift
+// bitchat
+//
+// Handles command parsing and execution for BitChat
+// This is free and unencumbered software released into the public domain.
+//
+
+import Foundation
+
+/// Result of command processing
+enum CommandResult {
+    case success(message: String?)
+    case error(message: String)
+    case handled  // Command handled, no message needed
+}
+
+/// Processes chat commands in a focused, efficient way
+@MainActor
+final class CommandProcessor {
+    weak var chatViewModel: ChatViewModel?
+    weak var meshService: Transport?
+    private let identityManager: SecureIdentityStateManagerProtocol
+    
+    init(chatViewModel: ChatViewModel? = nil, meshService: Transport? = nil, identityManager: SecureIdentityStateManagerProtocol) {
+        self.chatViewModel = chatViewModel
+        self.meshService = meshService
+        self.identityManager = identityManager
+    }
+    
+    /// Process a command string
+    @MainActor
+    func process(_ command: String) -> CommandResult {
+        let parts = command.split(separator: " ", maxSplits: 1, omittingEmptySubsequences: false)
+        guard let cmd = parts.first else { return .error(message: "Invalid command") }
+        let args = parts.count > 1 ? String(parts[1]) : ""
+        
+        // Geohash context: disable favoriting in public geohash or GeoDM
+        let inGeoPublic: Bool = {
+            switch LocationChannelManager.shared.selectedChannel {
+            case .mesh: return false
+            case .location: return true
+            }
+        }()
+        let inGeoDM = chatViewModel?.selectedPrivateChatPeer?.isGeoDM == true
+
+        switch cmd {
+        case "/m", "/msg":
+            return handleMessage(args)
+        case "/w", "/who":
+            return handleWho()
+        case "/clear":
+            return handleClear()
+        case "/hug":
+            return handleEmote(args, command: "hug", action: "hugs", emoji: "🫂")
+        case "/slap":
+            return handleEmote(args, command: "slap", action: "slaps", emoji: "🐟", suffix: " around a bit with a large trout")
+        case "/block":
+            return handleBlock(args)
+        case "/unblock":
+            return handleUnblock(args)
+        case "/fav":
+            if inGeoPublic || inGeoDM { return .error(message: "favorites are only for mesh peers in #mesh") }
+            return handleFavorite(args, add: true)
+        case "/unfav":
+            if inGeoPublic || inGeoDM { return .error(message: "favorites are only for mesh peers in #mesh") }
+            return handleFavorite(args, add: false)
+        default:
+            return .error(message: "unknown command: \(cmd)")
+        }
+    }
+
+    // MARK: - Command Handlers
+    
+    private func handleMessage(_ args: String) -> CommandResult {
+        let parts = args.split(separator: " ", maxSplits: 1, omittingEmptySubsequences: false)
+        guard !parts.isEmpty else {
+            return .error(message: "usage: /msg @nickname [message]")
+        }
+        
+        let targetName = String(parts[0])
+        let nickname = targetName.hasPrefix("@") ? String(targetName.dropFirst()) : targetName
+        
+        guard let peerID = chatViewModel?.getPeerIDForNickname(nickname) else {
+            return .error(message: "'\(nickname)' not found")
+        }
+        
+        chatViewModel?.startPrivateChat(with: peerID)
+        
+        if parts.count > 1 {
+            let message = String(parts[1])
+            chatViewModel?.sendPrivateMessage(message, to: peerID)
+        }
+        
+        return .success(message: "started private chat with \(nickname)")
+    }
+    
+    private func handleWho() -> CommandResult {
+        // Show geohash participants when in a geohash channel; otherwise mesh peers
+        switch LocationChannelManager.shared.selectedChannel {
+        case .location(let ch):
+            // Geohash context: show visible geohash participants (exclude self)
+            guard let vm = chatViewModel else { return .success(message: "nobody around") }
+            let myHex = (try? chatViewModel?.idBridge.deriveIdentity(forGeohash: ch.geohash))?.publicKeyHex.lowercased()
+            let people = vm.visibleGeohashPeople().filter { person in
+                if let me = myHex { return person.id.lowercased() != me }
+                return true
+            }
+            let names = people.map { $0.displayName }
+            if names.isEmpty { return .success(message: "no one else is online right now") }
+            return .success(message: "online: " + names.sorted().joined(separator: ", "))
+        case .mesh:
+            // Mesh context: show connected peer nicknames
+            guard let peers = meshService?.getPeerNicknames(), !peers.isEmpty else {
+                return .success(message: "no one else is online right now")
+            }
+            let onlineList = peers.values.sorted().joined(separator: ", ")
+            return .success(message: "online: \(onlineList)")
+        }
+    }
+    
+    private func handleClear() -> CommandResult {
+        if let peerID = chatViewModel?.selectedPrivateChatPeer {
+            chatViewModel?.privateChats[peerID]?.removeAll()
+        } else {
+            chatViewModel?.clearCurrentPublicTimeline()
+        }
+        return .handled
+    }
+    
+    private func handleEmote(_ args: String, command: String, action: String, emoji: String, suffix: String = "") -> CommandResult {
+        let targetName = args.trimmingCharacters(in: .whitespaces)
+        guard !targetName.isEmpty else {
+            return .error(message: "usage: /\(command) <nickname>")
+        }
+        
+        let nickname = targetName.hasPrefix("@") ? String(targetName.dropFirst()) : targetName
+        
+        guard let targetPeerID = chatViewModel?.getPeerIDForNickname(nickname),
+              let myNickname = chatViewModel?.nickname else {
+            return .error(message: "cannot \(command) \(nickname): not found")
+        }
+        
+        let emoteContent = "* \(emoji) \(myNickname) \(action) \(nickname)\(suffix) *"
+        
+        if chatViewModel?.selectedPrivateChatPeer != nil {
+            // In private chat
+            if let peerNickname = meshService?.peerNickname(peerID: targetPeerID) {
+                let personalMessage = "* \(emoji) \(myNickname) \(action) you\(suffix) *"
+                meshService?.sendPrivateMessage(personalMessage, to: targetPeerID,
+                                               recipientNickname: peerNickname,
+                                               messageID: UUID().uuidString)
+                // Also add a local system message so the sender sees a natural-language confirmation
+                let pastAction: String = {
+                    switch action {
+                    case "hugs": return "hugged"
+                    case "slaps": return "slapped"
+                    default: return action.hasSuffix("e") ? action + "d" : action + "ed"
+                    }
+                }()
+                let localText = "\(emoji) you \(pastAction) \(nickname)\(suffix)"
+                chatViewModel?.addLocalPrivateSystemMessage(localText, to: targetPeerID)
+            }
+        } else {
+            // In public chat: send to active public channel (mesh or geohash)
+            chatViewModel?.sendPublicRaw(emoteContent)
+            let publicEcho = "\(emoji) \(myNickname) \(action) \(nickname)\(suffix)"
+            chatViewModel?.addPublicSystemMessage(publicEcho)
+        }
+        
+        return .handled
+    }
+    
+    private func handleBlock(_ args: String) -> CommandResult {
+        let targetName = args.trimmingCharacters(in: .whitespaces)
+        
+        if targetName.isEmpty {
+            // List blocked users (mesh) and geohash (Nostr) blocks
+            let meshBlocked = chatViewModel?.blockedUsers ?? []
+            var blockedNicknames: [String] = []
+            if let peers = meshService?.getPeerNicknames() {
+                for (peerID, nickname) in peers {
+                    if let fingerprint = meshService?.getFingerprint(for: peerID),
+                       meshBlocked.contains(fingerprint) {
+                        blockedNicknames.append(nickname)
+                    }
+                }
+            }
+
+            // Geohash blocked names (prefer visible display names; fallback to #suffix)
+            let geoBlocked = Array(identityManager.getBlockedNostrPubkeys())
+            var geoNames: [String] = []
+            if let vm = chatViewModel {
+                let visible = vm.visibleGeohashPeople()
+                let visibleIndex = Dictionary(uniqueKeysWithValues: visible.map { ($0.id.lowercased(), $0.displayName) })
+                for pk in geoBlocked {
+                    if let name = visibleIndex[pk.lowercased()] {
+                        geoNames.append(name)
+                    } else {
+                        let suffix = String(pk.suffix(4))
+                        geoNames.append("anon#\(suffix)")
+                    }
+                }
+            }
+
+            let meshList = blockedNicknames.isEmpty ? "none" : blockedNicknames.sorted().joined(separator: ", ")
+            let geoList = geoNames.isEmpty ? "none" : geoNames.sorted().joined(separator: ", ")
+            return .success(message: "blocked peers: \(meshList) | geohash blocks: \(geoList)")
+        }
+        
+        let nickname = targetName.hasPrefix("@") ? String(targetName.dropFirst()) : targetName
+        
+        if let peerID = chatViewModel?.getPeerIDForNickname(nickname),
+           let fingerprint = meshService?.getFingerprint(for: peerID) {
+            if identityManager.isBlocked(fingerprint: fingerprint) {
+                return .success(message: "\(nickname) is already blocked")
+            }
+            // Block the user (mesh/noise identity)
+            if var identity = identityManager.getSocialIdentity(for: fingerprint) {
+                identity.isBlocked = true
+                identity.isFavorite = false
+                identityManager.updateSocialIdentity(identity)
+            } else {
+                let blockedIdentity = SocialIdentity(
+                    fingerprint: fingerprint,
+                    localPetname: nil,
+                    claimedNickname: nickname,
+                    trustLevel: .unknown,
+                    isFavorite: false,
+                    isBlocked: true,
+                    notes: nil
+                )
+                identityManager.updateSocialIdentity(blockedIdentity)
+            }
+            return .success(message: "blocked \(nickname). you will no longer receive messages from them")
+        }
+        // Mesh lookup failed; try geohash (Nostr) participant by display name
+        if let pub = chatViewModel?.nostrPubkeyForDisplayName(nickname) {
+            if identityManager.isNostrBlocked(pubkeyHexLowercased: pub) {
+                return .success(message: "\(nickname) is already blocked")
+            }
+            identityManager.setNostrBlocked(pub, isBlocked: true)
+            return .success(message: "blocked \(nickname) in geohash chats")
+        }
+        
+        return .error(message: "cannot block \(nickname): not found or unable to verify identity")
+    }
+    
+    private func handleUnblock(_ args: String) -> CommandResult {
+        let targetName = args.trimmingCharacters(in: .whitespaces)
+        guard !targetName.isEmpty else {
+            return .error(message: "usage: /unblock <nickname>")
+        }
+        
+        let nickname = targetName.hasPrefix("@") ? String(targetName.dropFirst()) : targetName
+        
+        if let peerID = chatViewModel?.getPeerIDForNickname(nickname),
+           let fingerprint = meshService?.getFingerprint(for: peerID) {
+            if !identityManager.isBlocked(fingerprint: fingerprint) {
+                return .success(message: "\(nickname) is not blocked")
+            }
+            identityManager.setBlocked(fingerprint, isBlocked: false)
+            return .success(message: "unblocked \(nickname)")
+        }
+        // Try geohash unblock
+        if let pub = chatViewModel?.nostrPubkeyForDisplayName(nickname) {
+            if !identityManager.isNostrBlocked(pubkeyHexLowercased: pub) {
+                return .success(message: "\(nickname) is not blocked")
+            }
+            identityManager.setNostrBlocked(pub, isBlocked: false)
+            return .success(message: "unblocked \(nickname) in geohash chats")
+        }
+        return .error(message: "cannot unblock \(nickname): not found")
+    }
+    
+    private func handleFavorite(_ args: String, add: Bool) -> CommandResult {
+        let targetName = args.trimmingCharacters(in: .whitespaces)
+        guard !targetName.isEmpty else {
+            return .error(message: "usage: /\(add ? "fav" : "unfav") <nickname>")
+        }
+        
+        let nickname = targetName.hasPrefix("@") ? String(targetName.dropFirst()) : targetName
+        
+        guard let peerID = chatViewModel?.getPeerIDForNickname(nickname),
+              let noisePublicKey = Data(hexString: peerID.id) else {
+            return .error(message: "can't find peer: \(nickname)")
+        }
+        
+        if add {
+            let existingFavorite = FavoritesPersistenceService.shared.getFavoriteStatus(for: noisePublicKey)
+            FavoritesPersistenceService.shared.addFavorite(
+                peerNoisePublicKey: noisePublicKey,
+                peerNostrPublicKey: existingFavorite?.peerNostrPublicKey,
+                peerNickname: nickname
+            )
+            
+            chatViewModel?.toggleFavorite(peerID: peerID)
+            chatViewModel?.sendFavoriteNotification(to: peerID, isFavorite: true)
+            
+            return .success(message: "added \(nickname) to favorites")
+        } else {
+            FavoritesPersistenceService.shared.removeFavorite(peerNoisePublicKey: noisePublicKey)
+            
+            chatViewModel?.toggleFavorite(peerID: peerID)
+            chatViewModel?.sendFavoriteNotification(to: peerID, isFavorite: false)
+            
+            return .success(message: "removed \(nickname) from favorites")
+        }
+    }
+    
+}

bitchat/Services/DeliveryTracker.swift

@@ -1,294 +0,0 @@
-//
-// DeliveryTracker.swift
-// bitchat
-//
-// This is free and unencumbered software released into the public domain.
-// For more information, see <https://unlicense.org>
-//
-
-import Foundation
-import Combine
-
-class DeliveryTracker {
-    static let shared = DeliveryTracker()
-    
-    // Track pending deliveries
-    private var pendingDeliveries: [String: PendingDelivery] = [:]
-    private let pendingLock = NSLock()
-    
-    // Track received ACKs to prevent duplicates
-    private var receivedAckIDs = Set<String>()
-    private var sentAckIDs = Set<String>()
-    
-    // Timeout configuration
-    private let privateMessageTimeout: TimeInterval = 120  // 2 minutes
-    private let roomMessageTimeout: TimeInterval = 180     // 3 minutes
-    private let favoriteTimeout: TimeInterval = 600       // 10 minutes for favorites
-    
-    // Retry configuration
-    private let maxRetries = 3
-    private let retryDelay: TimeInterval = 5  // Base retry delay
-    
-    // Publishers for UI updates
-    let deliveryStatusUpdated = PassthroughSubject<(messageID: String, status: DeliveryStatus), Never>()
-    
-    // Cleanup timer
-    private var cleanupTimer: Timer?
-    
-    struct PendingDelivery {
-        let messageID: String
-        let sentAt: Date
-        let recipientID: String
-        let recipientNickname: String
-        let retryCount: Int
-        let isFavorite: Bool
-        var timeoutTimer: Timer?
-        
-        var isTimedOut: Bool {
-            let timeout: TimeInterval = isFavorite ? 300 : 30
-            return Date().timeIntervalSince(sentAt) > timeout
-        }
-        
-        var shouldRetry: Bool {
-            return retryCount < 3 && isFavorite
-        }
-    }
-    
-    private init() {
-        startCleanupTimer()
-    }
-    
-    deinit {
-        cleanupTimer?.invalidate()
-    }
-    
-    // MARK: - Public Methods
-    
-    func trackMessage(_ message: BitchatMessage, recipientID: String, recipientNickname: String, isFavorite: Bool = false, expectedRecipients: Int = 1) {
-        // Only track private messages
-        guard message.isPrivate else { return }
-        
-        SecureLogger.log("Tracking message \(message.id) - private: \(message.isPrivate), recipient: \(recipientNickname)", category: SecureLogger.session, level: .info)
-        
-        
-        let delivery = PendingDelivery(
-            messageID: message.id,
-            sentAt: Date(),
-            recipientID: recipientID,
-            recipientNickname: recipientNickname,
-            retryCount: 0,
-            isFavorite: isFavorite,
-            timeoutTimer: nil
-        )
-        
-        // Store the delivery with lock
-        pendingLock.lock()
-        pendingDeliveries[message.id] = delivery
-        pendingLock.unlock()
-        
-        // Update status to sent (only if not already delivered)
-        DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) { [weak self] in
-            guard let self = self else { return }
-            
-            self.pendingLock.lock()
-            let stillPending = self.pendingDeliveries[message.id] != nil
-            self.pendingLock.unlock()
-            
-            // Only update to sent if still pending (not already delivered)
-            if stillPending {
-                SecureLogger.log("Updating message \(message.id) to sent status (still pending)", category: SecureLogger.session, level: .debug)
-                self.updateDeliveryStatus(message.id, status: .sent)
-            } else {
-                SecureLogger.log("Skipping sent status update for \(message.id) - already delivered", category: SecureLogger.session, level: .debug)
-            }
-        }
-        
-        // Schedule timeout (outside of lock)
-        scheduleTimeout(for: message.id)
-    }
-    
-    func processDeliveryAck(_ ack: DeliveryAck) {
-        pendingLock.lock()
-        defer { pendingLock.unlock() }
-        
-        SecureLogger.log("Processing delivery ACK for message \(ack.originalMessageID) from \(ack.recipientNickname)", category: SecureLogger.session, level: .info)
-        
-        // Prevent duplicate ACK processing
-        guard !receivedAckIDs.contains(ack.ackID) else {
-            SecureLogger.log("Duplicate ACK \(ack.ackID) - ignoring", category: SecureLogger.session, level: .warning)
-            return
-        }
-        receivedAckIDs.insert(ack.ackID)
-        
-        // Find the pending delivery
-        guard let delivery = pendingDeliveries[ack.originalMessageID] else {
-            // Message might have already been delivered or timed out
-            SecureLogger.log("No pending delivery found for message \(ack.originalMessageID)", category: SecureLogger.session, level: .warning)
-            return
-        }
-        
-        // Cancel timeout timer
-        delivery.timeoutTimer?.invalidate()
-        
-        // Direct message - mark as delivered
-        SecureLogger.log("Marking private message \(ack.originalMessageID) as delivered to \(ack.recipientNickname)", category: SecureLogger.session, level: .info)
-        updateDeliveryStatus(ack.originalMessageID, status: .delivered(to: ack.recipientNickname, at: Date()))
-        pendingDeliveries.removeValue(forKey: ack.originalMessageID)
-    }
-    
-    func generateAck(for message: BitchatMessage, myPeerID: String, myNickname: String, hopCount: UInt8) -> DeliveryAck? {
-        // Don't ACK our own messages
-        guard message.senderPeerID != myPeerID else { 
-            return nil 
-        }
-        
-        // Only ACK private messages
-        guard message.isPrivate else { 
-            return nil 
-        }
-        
-        // Don't ACK if we've already sent an ACK for this message
-        guard !sentAckIDs.contains(message.id) else { 
-            return nil 
-        }
-        sentAckIDs.insert(message.id)
-        
-        
-        return DeliveryAck(
-            originalMessageID: message.id,
-            recipientID: myPeerID,
-            recipientNickname: myNickname,
-            hopCount: hopCount
-        )
-    }
-    
-    func clearDeliveryStatus(for messageID: String) {
-        pendingLock.lock()
-        defer { pendingLock.unlock() }
-        
-        if let delivery = pendingDeliveries[messageID] {
-            delivery.timeoutTimer?.invalidate()
-        }
-        pendingDeliveries.removeValue(forKey: messageID)
-    }
-    
-    // MARK: - Private Methods
-    
-    private func updateDeliveryStatus(_ messageID: String, status: DeliveryStatus) {
-        SecureLogger.log("Updating delivery status for message \(messageID): \(status)", category: SecureLogger.session, level: .debug)
-        DispatchQueue.main.async { [weak self] in
-            self?.deliveryStatusUpdated.send((messageID: messageID, status: status))
-        }
-    }
-    
-    private func scheduleTimeout(for messageID: String) {
-        // Get delivery info with lock
-        pendingLock.lock()
-        guard let delivery = pendingDeliveries[messageID] else {
-            pendingLock.unlock()
-            return
-        }
-        let isFavorite = delivery.isFavorite
-        pendingLock.unlock()
-        
-        let timeout = isFavorite ? favoriteTimeout : privateMessageTimeout
-        
-        let timer = Timer.scheduledTimer(withTimeInterval: timeout, repeats: false) { [weak self] _ in
-            self?.handleTimeout(messageID: messageID)
-        }
-        
-        pendingLock.lock()
-        if var updatedDelivery = pendingDeliveries[messageID] {
-            updatedDelivery.timeoutTimer = timer
-            pendingDeliveries[messageID] = updatedDelivery
-        }
-        pendingLock.unlock()
-    }
-    
-    private func handleTimeout(messageID: String) {
-        pendingLock.lock()
-        guard let delivery = pendingDeliveries[messageID] else {
-            pendingLock.unlock()
-            return
-        }
-        
-        let shouldRetry = delivery.shouldRetry
-        
-        if shouldRetry {
-            pendingLock.unlock()
-            // Retry for favorites (outside of lock)
-            retryDelivery(messageID: messageID)
-        } else {
-            // Mark as failed
-            let reason = "Message not delivered"
-            pendingDeliveries.removeValue(forKey: messageID)
-            pendingLock.unlock()
-            updateDeliveryStatus(messageID, status: .failed(reason: reason))
-        }
-    }
-    
-    private func retryDelivery(messageID: String) {
-        pendingLock.lock()
-        guard let delivery = pendingDeliveries[messageID] else {
-            pendingLock.unlock()
-            return
-        }
-        
-        // Increment retry count
-        let newDelivery = PendingDelivery(
-            messageID: delivery.messageID,
-            sentAt: delivery.sentAt,
-            recipientID: delivery.recipientID,
-            recipientNickname: delivery.recipientNickname,
-            retryCount: delivery.retryCount + 1,
-            isFavorite: delivery.isFavorite,
-            timeoutTimer: nil
-        )
-        
-        pendingDeliveries[messageID] = newDelivery
-        let retryCount = delivery.retryCount
-        pendingLock.unlock()
-        
-        // Exponential backoff for retry
-        let delay = retryDelay * pow(2, Double(retryCount))
-        
-        DispatchQueue.main.asyncAfter(deadline: .now() + delay) { [weak self] in
-            // Trigger resend through delegate or notification
-            NotificationCenter.default.post(
-                name: Notification.Name("bitchat.retryMessage"),
-                object: nil,
-                userInfo: ["messageID": messageID]
-            )
-            
-            // Schedule new timeout
-            self?.scheduleTimeout(for: messageID)
-        }
-    }
-    
-    private func startCleanupTimer() {
-        cleanupTimer = Timer.scheduledTimer(withTimeInterval: 60, repeats: true) { [weak self] _ in
-            self?.cleanupOldDeliveries()
-        }
-    }
-    
-    private func cleanupOldDeliveries() {
-        pendingLock.lock()
-        defer { pendingLock.unlock() }
-        
-        let now = Date()
-        let maxAge: TimeInterval = 3600  // 1 hour
-        
-        // Clean up old pending deliveries
-        pendingDeliveries = pendingDeliveries.filter { (_, delivery) in
-            now.timeIntervalSince(delivery.sentAt) < maxAge
-        }
-        
-        // Clean up old ACK IDs (keep last 1000)
-        if receivedAckIDs.count > 1000 {
-            receivedAckIDs.removeAll()
-        }
-        if sentAckIDs.count > 1000 {
-            sentAckIDs.removeAll()
-        }
-    }
-}

bitchat/Services/FavoritesPersistenceService.swift

@@ -0,0 +1,314 @@
+import BitLogger
+import Foundation
+import Combine
+
+/// Manages persistent favorite relationships between peers
+@MainActor
+final class FavoritesPersistenceService: ObservableObject {
+    
+    struct FavoriteRelationship: Codable {
+        let peerNoisePublicKey: Data
+        let peerNostrPublicKey: String?
+        let peerNickname: String
+        let isFavorite: Bool
+        let theyFavoritedUs: Bool
+        let favoritedAt: Date
+        let lastUpdated: Date
+        // Track what we last sent as OUR npub to this peer, to avoid resending unless it changes
+        // Note: we do not track which npub we last sent to them; sending happens only on favorite toggle
+        
+        var isMutual: Bool {
+            isFavorite && theyFavoritedUs
+        }
+    }
+    
+    // We intentionally do not track when we last sent our npub; sending happens only on favorite toggle.
+
+    private static let storageKey = "chat.bitchat.favorites"
+    private static let keychainService = "chat.bitchat.favorites"
+    private let keychain: KeychainHelperProtocol
+    
+    @Published private(set) var favorites: [Data: FavoriteRelationship] = [:] // Noise pubkey -> relationship
+    @Published private(set) var mutualFavorites: Set<Data> = []
+    
+    private let userDefaults = UserDefaults.standard
+    private var cancellables = Set<AnyCancellable>()
+    
+    static let shared = FavoritesPersistenceService()
+    
+    init(keychain: KeychainHelperProtocol = KeychainHelper()) {
+        self.keychain = keychain
+        loadFavorites()
+        
+        // Update mutual favorites when favorites change
+        $favorites
+            .map { favorites in
+                Set(favorites.compactMap { $0.value.isMutual ? $0.key : nil })
+            }
+            .assign(to: &$mutualFavorites)
+    }
+    
+    /// Add or update a favorite
+    func addFavorite(
+        peerNoisePublicKey: Data,
+        peerNostrPublicKey: String? = nil,
+        peerNickname: String
+    ) {
+        SecureLogger.info("⭐️ Adding favorite: \(peerNickname) (\(peerNoisePublicKey.hexEncodedString()))", category: .session)
+        
+        let existing = favorites[peerNoisePublicKey]
+        
+        let relationship = FavoriteRelationship(
+            peerNoisePublicKey: peerNoisePublicKey,
+            peerNostrPublicKey: peerNostrPublicKey ?? existing?.peerNostrPublicKey,
+            peerNickname: peerNickname,
+            isFavorite: true,
+            theyFavoritedUs: existing?.theyFavoritedUs ?? false,
+            favoritedAt: existing?.favoritedAt ?? Date(),
+            lastUpdated: Date()
+        )
+        
+        // Log if this creates a mutual favorite
+        if relationship.isMutual {
+            SecureLogger.info("💕 Mutual favorite relationship established with \(peerNickname)!", category: .session)
+        }
+        
+        favorites[peerNoisePublicKey] = relationship
+        saveFavorites()
+        
+        // Notify observers
+        NotificationCenter.default.post(
+            name: .favoriteStatusChanged,
+            object: nil,
+            userInfo: ["peerPublicKey": peerNoisePublicKey]
+        )
+    }
+    
+    /// Remove a favorite
+    func removeFavorite(peerNoisePublicKey: Data) {
+        guard let existing = favorites[peerNoisePublicKey] else { return }
+        
+        SecureLogger.info("⭐️ Removing favorite: \(existing.peerNickname) (\(peerNoisePublicKey.hexEncodedString()))", category: .session)
+        
+        // If they still favorite us, keep the record but mark us as not favoriting
+        if existing.theyFavoritedUs {
+            let updated = FavoriteRelationship(
+                peerNoisePublicKey: existing.peerNoisePublicKey,
+                peerNostrPublicKey: existing.peerNostrPublicKey,
+                peerNickname: existing.peerNickname,
+                isFavorite: false,
+                theyFavoritedUs: true,
+                favoritedAt: existing.favoritedAt,
+                lastUpdated: Date()
+            )
+            favorites[peerNoisePublicKey] = updated
+            // Keeping record - they still favorite us
+        } else {
+            // Neither side favorites, remove completely
+            favorites.removeValue(forKey: peerNoisePublicKey)
+            // Completely removed from favorites
+        }
+        
+        saveFavorites()
+        
+        // Notify observers
+        NotificationCenter.default.post(
+            name: .favoriteStatusChanged,
+            object: nil,
+            userInfo: ["peerPublicKey": peerNoisePublicKey]
+        )
+    }
+    
+    /// Update when we learn a peer favorited/unfavorited us
+    func updatePeerFavoritedUs(
+        peerNoisePublicKey: Data,
+        favorited: Bool,
+        peerNickname: String? = nil,
+        peerNostrPublicKey: String? = nil
+    ) {
+        let existing = favorites[peerNoisePublicKey]
+        let displayName = peerNickname ?? existing?.peerNickname ?? "Unknown"
+        
+        SecureLogger.info("📨 Received favorite notification: \(displayName) \(favorited ? "favorited" : "unfavorited") us", category: .session)
+        
+        let relationship = FavoriteRelationship(
+            peerNoisePublicKey: peerNoisePublicKey,
+            peerNostrPublicKey: peerNostrPublicKey ?? existing?.peerNostrPublicKey,
+            peerNickname: displayName,
+            isFavorite: existing?.isFavorite ?? false,
+            theyFavoritedUs: favorited,
+            favoritedAt: existing?.favoritedAt ?? Date(),
+            lastUpdated: Date()
+        )
+        
+        if !relationship.isFavorite && !relationship.theyFavoritedUs {
+            // Neither side favorites, remove completely
+            favorites.removeValue(forKey: peerNoisePublicKey)
+            // Removed - neither side favorites anymore
+        } else {
+            favorites[peerNoisePublicKey] = relationship
+            
+            // Check if this creates a mutual favorite
+            if relationship.isMutual {
+                SecureLogger.info("💕 Mutual favorite relationship established with \(displayName)!", category: .session)
+            }
+        }
+        
+        saveFavorites()
+        
+        // Notify observers
+        NotificationCenter.default.post(
+            name: .favoriteStatusChanged,
+            object: nil,
+            userInfo: ["peerPublicKey": peerNoisePublicKey]
+        )
+    }
+    
+    /// Check if a peer is favorited by us
+    func isFavorite(_ peerNoisePublicKey: Data) -> Bool {
+        favorites[peerNoisePublicKey]?.isFavorite ?? false
+    }
+    
+    /// Check if we have a mutual favorite relationship
+    func isMutualFavorite(_ peerNoisePublicKey: Data) -> Bool {
+        favorites[peerNoisePublicKey]?.isMutual ?? false
+    }
+    
+    /// Get favorite status for a peer
+    func getFavoriteStatus(for peerNoisePublicKey: Data) -> FavoriteRelationship? {
+        favorites[peerNoisePublicKey]
+    }
+
+    /// Resolve favorite status by short peer ID (16-hex derived from Noise pubkey)
+    /// Falls back to scanning favorites and matching on derived peer ID.
+    func getFavoriteStatus(forPeerID peerID: PeerID) -> FavoriteRelationship? {
+        // Quick sanity: peerID should be 16 hex chars (8 bytes)
+        guard peerID.isShort else { return nil }
+        for (pubkey, rel) in favorites where PeerID(publicKey: pubkey) == peerID {
+            return rel
+        }
+        return nil
+    }
+    
+    /// Clear all favorites - used for panic mode
+    func clearAllFavorites() {
+        SecureLogger.warning("🧹 Clearing all favorites (panic mode)", category: .session)
+        
+        favorites.removeAll()
+        saveFavorites()
+        
+        // Delete from keychain directly
+        keychain.delete(
+            key: Self.storageKey,
+            service: Self.keychainService
+        )
+        
+        // Post notification for UI update
+        NotificationCenter.default.post(name: .favoriteStatusChanged, object: nil)
+    }
+    
+    // MARK: - Persistence
+    
+    private func saveFavorites() {
+        let relationships = Array(favorites.values)
+        // Saving favorite relationships to keychain
+        
+        do {
+            let encoder = JSONEncoder()
+            let data = try encoder.encode(relationships)
+            
+            // Store in keychain for security
+            keychain.save(
+                key: Self.storageKey,
+                data: data,
+                service: Self.keychainService,
+                accessible: nil
+            )
+            
+            // Successfully saved favorites
+        } catch {
+            SecureLogger.error("Failed to save favorites: \(error)", category: .session)
+        }
+    }
+    
+    private func loadFavorites() {
+        // Loading favorites from keychain
+        
+        guard let data = keychain.load(
+            key: Self.storageKey,
+            service: Self.keychainService
+        ) else { 
+            return 
+        }
+        
+        do {
+            let decoder = JSONDecoder()
+            let relationships = try decoder.decode([FavoriteRelationship].self, from: data)
+            
+            SecureLogger.info("✅ Loaded \(relationships.count) favorite relationships", category: .session)
+            
+            // Log Nostr public key info
+            for relationship in relationships {
+                if relationship.peerNostrPublicKey == nil {
+                    SecureLogger.warning("⚠️ No Nostr public key stored for '\(relationship.peerNickname)'", category: .session)
+                }
+            }
+            
+            // Convert to dictionary, cleaning up duplicates by public key (not nickname)
+            var seenPublicKeys: [Data: FavoriteRelationship] = [:]
+            var cleanedRelationships: [FavoriteRelationship] = []
+            
+            for relationship in relationships {
+                // Check for duplicates by public key (the actual unique identifier)
+                if let existing = seenPublicKeys[relationship.peerNoisePublicKey] {
+                    SecureLogger.warning("⚠️ Duplicate favorite found for public key \(relationship.peerNoisePublicKey.hexEncodedString()) - nicknames: '\(existing.peerNickname)' vs '\(relationship.peerNickname)'", category: .session)
+                    
+                    // Keep the most recent or most complete relationship
+                    if relationship.lastUpdated > existing.lastUpdated ||
+                       (relationship.peerNostrPublicKey != nil && existing.peerNostrPublicKey == nil) {
+                        // Replace with newer/more complete entry
+                        seenPublicKeys[relationship.peerNoisePublicKey] = relationship
+                        cleanedRelationships.removeAll { $0.peerNoisePublicKey == relationship.peerNoisePublicKey }
+                        cleanedRelationships.append(relationship)
+                    }
+                } else {
+                    seenPublicKeys[relationship.peerNoisePublicKey] = relationship
+                    cleanedRelationships.append(relationship)
+                }
+            }
+            
+            // If we cleaned up duplicates, save the cleaned list
+            if cleanedRelationships.count < relationships.count {
+                // Cleaned up duplicates
+                
+                // Clear and rebuild favorites dictionary
+                favorites.removeAll()
+                for relationship in cleanedRelationships {
+                    favorites[relationship.peerNoisePublicKey] = relationship
+                }
+                
+                // Save cleaned favorites
+                saveFavorites()
+                
+                // Notify that favorites have been cleaned up (synchronously since we're already on main actor)
+                NotificationCenter.default.post(name: .favoriteStatusChanged, object: nil)
+            } else {
+                // No duplicates, just populate normally
+                for relationship in cleanedRelationships {
+                    favorites[relationship.peerNoisePublicKey] = relationship
+                }
+            }
+            
+            // Log loaded relationships
+            // Loaded relationships successfully
+        } catch {
+            SecureLogger.error("Failed to load favorites: \(error)", category: .session)
+        }
+    }
+}
+
+// MARK: - Notification Names
+
+extension Notification.Name {
+    static let favoriteStatusChanged = Notification.Name("FavoriteStatusChanged")
+}

bitchat/Services/GeohashBookmarksStore.swift

@@ -0,0 +1,219 @@
+import Foundation
+import Combine
+#if os(iOS) || os(macOS)
+import CoreLocation
+#endif
+
+/// Stores a user-maintained list of bookmarked geohash channels.
+/// - Persistence: UserDefaults (JSON string array)
+/// - Semantics: geohashes are normalized to lowercase base32 and de-duplicated
+final class GeohashBookmarksStore: ObservableObject {
+    static let shared = GeohashBookmarksStore()
+
+    @Published private(set) var bookmarks: [String] = []
+    @Published private(set) var bookmarkNames: [String: String] = [:] // geohash -> friendly name
+
+    private let storeKey = "locationChannel.bookmarks"
+    private let namesStoreKey = "locationChannel.bookmarkNames"
+    private var membership: Set<String> = []
+    #if os(iOS) || os(macOS)
+    private let geocoder = CLGeocoder()
+    private var resolving: Set<String> = []
+    #endif
+    
+    private let storage: UserDefaults
+
+    init(storage: UserDefaults = .standard) {
+        self.storage = storage
+        load()
+    }
+
+    // MARK: - Public API
+    func isBookmarked(_ geohash: String) -> Bool {
+        return membership.contains(Self.normalize(geohash))
+    }
+
+    func toggle(_ geohash: String) {
+        let gh = Self.normalize(geohash)
+        if membership.contains(gh) {
+            remove(gh)
+        } else {
+            add(gh)
+        }
+    }
+
+    func add(_ geohash: String) {
+        let gh = Self.normalize(geohash)
+        guard !gh.isEmpty else { return }
+        guard !membership.contains(gh) else { return }
+        bookmarks.insert(gh, at: 0)
+        membership.insert(gh)
+        persist()
+        // Resolve and persist a friendly name once when added
+        resolveNameIfNeeded(for: gh)
+    }
+
+    func remove(_ geohash: String) {
+        let gh = Self.normalize(geohash)
+        guard membership.contains(gh) else { return }
+        if let idx = bookmarks.firstIndex(of: gh) { bookmarks.remove(at: idx) }
+        membership.remove(gh)
+        // Clean up stored name to avoid stale cache growth
+        if bookmarkNames.removeValue(forKey: gh) != nil {
+            persistNames()
+        }
+        persist()
+    }
+
+    // MARK: - Persistence
+    private func load() {
+        guard let data = storage.data(forKey: storeKey) else { return }
+        if let arr = try? JSONDecoder().decode([String].self, from: data) {
+            // Sanitize, normalize, dedupe while preserving order (first occurrence wins)
+            var seen = Set<String>()
+            var list: [String] = []
+            for raw in arr {
+                let gh = Self.normalize(raw)
+                guard !gh.isEmpty else { continue }
+                if !seen.contains(gh) {
+                    seen.insert(gh)
+                    list.append(gh)
+                }
+            }
+            bookmarks = list
+            membership = seen
+        }
+        // Load any saved names
+        if let namesData = storage.data(forKey: namesStoreKey),
+           let dict = try? JSONDecoder().decode([String: String].self, from: namesData) {
+            bookmarkNames = dict
+        }
+    }
+
+    private func persist() {
+        if let data = try? JSONEncoder().encode(bookmarks) {
+            storage.set(data, forKey: storeKey)
+        }
+    }
+
+    private func persistNames() {
+        if let data = try? JSONEncoder().encode(bookmarkNames) {
+            storage.set(data, forKey: namesStoreKey)
+        }
+    }
+
+    // MARK: - Helpers
+    private static func normalize(_ s: String) -> String {
+        let allowed = Set("0123456789bcdefghjkmnpqrstuvwxyz")
+        return s
+            .trimmingCharacters(in: .whitespacesAndNewlines)
+            .lowercased()
+            .replacingOccurrences(of: "#", with: "")
+            .filter { allowed.contains($0) }
+    }
+
+    // MARK: - Name Resolution
+    /// Attempt to resolve and persist a friendly place name for a bookmarked geohash.
+    func resolveNameIfNeeded(for geohash: String) {
+        let gh = Self.normalize(geohash)
+        guard !gh.isEmpty else { return }
+        if bookmarkNames[gh] != nil { return }
+        #if os(iOS) || os(macOS)
+        if resolving.contains(gh) { return }
+        resolving.insert(gh)
+        // For very coarse geohashes, sample multiple points to capture multiple admin areas
+        if gh.count <= 2 {
+            let b = Geohash.decodeBounds(gh)
+            let pts: [CLLocation] = [
+                CLLocation(latitude: (b.latMin + b.latMax) / 2, longitude: (b.lonMin + b.lonMax) / 2), // center
+                CLLocation(latitude: b.latMin, longitude: b.lonMin),
+                CLLocation(latitude: b.latMin, longitude: b.lonMax),
+                CLLocation(latitude: b.latMax, longitude: b.lonMin),
+                CLLocation(latitude: b.latMax, longitude: b.lonMax)
+            ]
+            resolveCompositeAdminName(geohash: gh, points: pts)
+        } else {
+            let center = Geohash.decodeCenter(gh)
+            let loc = CLLocation(latitude: center.lat, longitude: center.lon)
+            geocoder.reverseGeocodeLocation(loc) { [weak self] placemarks, _ in
+                guard let self = self else { return }
+                defer { self.resolving.remove(gh) }
+                if let pm = placemarks?.first {
+                    let name = Self.nameForGeohashLength(gh.count, from: pm)
+                    if let name = name, !name.isEmpty {
+                        DispatchQueue.main.async {
+                            self.bookmarkNames[gh] = name
+                            self.persistNames()
+                        }
+                    }
+                }
+            }
+        }
+        #endif
+    }
+
+    #if os(iOS) || os(macOS)
+    private func resolveCompositeAdminName(geohash gh: String, points: [CLLocation]) {
+        var uniqueAdmins = OrderedSet<String>()
+        var idx = 0
+        func step() {
+            if idx >= points.count {
+                // Compose up to 2 names joined by ' and '
+                let finalName: String? = {
+                    let names = uniqueAdmins.array
+                    if names.count >= 2 { return names[0] + " and " + names[1] }
+                    return names.first
+                }()
+                if let finalName = finalName, !finalName.isEmpty {
+                    DispatchQueue.main.async {
+                        self.bookmarkNames[gh] = finalName
+                        self.persistNames()
+                    }
+                }
+                self.resolving.remove(gh)
+                return
+            }
+            let loc = points[idx]
+            idx += 1
+            geocoder.reverseGeocodeLocation(loc) { [weak self] placemarks, _ in
+                guard self != nil else { return }
+                if let pm = placemarks?.first {
+                    if let admin = pm.administrativeArea, !admin.isEmpty {
+                        uniqueAdmins.insert(admin)
+                    } else if let country = pm.country, !country.isEmpty {
+                        uniqueAdmins.insert(country)
+                    }
+                }
+                // Proceed to next point
+                step()
+            }
+        }
+        step()
+    }
+
+    // Minimal ordered-set for stable joining
+    private struct OrderedSet<Element: Hashable> {
+        private var set: Set<Element> = []
+        private(set) var array: [Element] = []
+        mutating func insert(_ element: Element) {
+            if set.insert(element).inserted { array.append(element) }
+        }
+    }
+
+    private static func nameForGeohashLength(_ len: Int, from pm: CLPlacemark) -> String? {
+        switch len {
+        case 0...2:
+            // Prefer administrative area if available at this coarse level
+            return pm.administrativeArea ?? pm.country
+        case 3...4:
+            return pm.administrativeArea ?? pm.subAdministrativeArea ?? pm.country
+        case 5:
+            return pm.locality ?? pm.subAdministrativeArea ?? pm.administrativeArea
+        case 6...7:
+            return pm.subLocality ?? pm.locality ?? pm.administrativeArea
+        default:
+            return pm.subLocality ?? pm.locality ?? pm.administrativeArea ?? pm.country
+        }
+    }
+    #endif
+}

bitchat/Services/KeychainManager.swift

@@ -6,101 +6,33 @@
 // For more information, see <https://unlicense.org>
 //
 
+import BitLogger
 import Foundation
 import Security
-import os.log
 
-class KeychainManager {
-    static let shared = KeychainManager()
+protocol KeychainManagerProtocol {
+    func saveIdentityKey(_ keyData: Data, forKey key: String) -> Bool
+    func getIdentityKey(forKey key: String) -> Data?
+    func deleteIdentityKey(forKey key: String) -> Bool
+    func deleteAllKeychainData() -> Bool
     
+    func secureClear(_ data: inout Data)
+    func secureClear(_ string: inout String)
+    
+    func verifyIdentityKeyExists() -> Bool
+}
+
+final class KeychainManager: KeychainManagerProtocol {
     // Use consistent service name for all keychain items
-    private let service = "chat.bitchat"
-    private let appGroup = "group.chat.bitchat"
-    
-    private init() {
-        // Clean up legacy keychain items on first run
-        cleanupLegacyKeychainItems()
-    }
-    
-    private func cleanupLegacyKeychainItems() {
-        // Check if we've already done cleanup
-        let cleanupKey = "bitchat.keychain.cleanup.v2"
-        if UserDefaults.standard.bool(forKey: cleanupKey) {
-            return
-        }
-        
-        
-        // List of old service names to migrate from
-        let legacyServices = [
-            "com.bitchat.passwords",
-            "com.bitchat.deviceidentity",
-            "com.bitchat.noise.identity",
-            "chat.bitchat.passwords",
-            "bitchat.keychain"
-        ]
-        
-        var migratedItems = 0
-        
-        // Try to migrate identity keys
-        for oldService in legacyServices {
-            // Check for noise identity key
-            let query: [String: Any] = [
-                kSecClass as String: kSecClassGenericPassword,
-                kSecAttrService as String: oldService,
-                kSecAttrAccount as String: "identity_noiseStaticKey",
-                kSecReturnData as String: true
-            ]
-            
-            var result: AnyObject?
-            let status = SecItemCopyMatching(query as CFDictionary, &result)
-            
-            if status == errSecSuccess, let data = result as? Data {
-                // Save to new service
-                if saveIdentityKey(data, forKey: "noiseStaticKey") {
-                    migratedItems += 1
-                    SecureLogger.logKeyOperation("migrate", keyType: "noiseStaticKey", success: true)
-                }
-                // Delete from old service
-                let deleteQuery: [String: Any] = [
-                    kSecClass as String: kSecClassGenericPassword,
-                    kSecAttrService as String: oldService,
-                    kSecAttrAccount as String: "identity_noiseStaticKey"
-                ]
-                SecItemDelete(deleteQuery as CFDictionary)
-            }
-        }
-        
-        // Clean up all other legacy items
-        for oldService in legacyServices {
-            let deleteQuery: [String: Any] = [
-                kSecClass as String: kSecClassGenericPassword,
-                kSecAttrService as String: oldService
-            ]
-            
-            SecItemDelete(deleteQuery as CFDictionary)
-        }
-        
-        
-        // Mark cleanup as done
-        UserDefaults.standard.set(true, forKey: cleanupKey)
-    }
-    
-    
-    private func isSandboxed() -> Bool {
-        #if os(macOS)
-        let environment = ProcessInfo.processInfo.environment
-        return environment["APP_SANDBOX_CONTAINER_ID"] != nil
-        #else
-        return false
-        #endif
-    }
+    private let service = BitchatApp.bundleID
+    private let appGroup = "group.\(BitchatApp.bundleID)"
     
     // MARK: - Identity Keys
     
     func saveIdentityKey(_ keyData: Data, forKey key: String) -> Bool {
         let fullKey = "identity_\(key)"
         let result = saveData(keyData, forKey: fullKey)
-        SecureLogger.logKeyOperation("save", keyType: key, success: result)
+        SecureLogger.logKeyOperation(.save, keyType: key, success: result)
         return result
     }
     
@@ -111,7 +43,7 @@ class KeychainManager {
     
     func deleteIdentityKey(forKey key: String) -> Bool {
         let result = delete(forKey: "identity_\(key)")
-        SecureLogger.logKeyOperation("delete", keyType: key, success: result)
+        SecureLogger.logKeyOperation(.delete, keyType: key, success: result)
         return result
     }
     
@@ -126,39 +58,44 @@ class KeychainManager {
         // Delete any existing item first to ensure clean state
         _ = delete(forKey: key)
         
-        // Build query with all necessary attributes for sandboxed apps
-        var query: [String: Any] = [
+        // Build base query
+        var base: [String: Any] = [
             kSecClass as String: kSecClassGenericPassword,
             kSecAttrAccount as String: key,
             kSecValueData as String: data,
             kSecAttrService as String: service,
-            // Important for sandboxed apps: make it accessible when unlocked
-            kSecAttrAccessible as String: kSecAttrAccessibleWhenUnlocked
+            kSecAttrAccessible as String: kSecAttrAccessibleWhenUnlocked,
+            kSecAttrLabel as String: "bitchat-\(key)"
         ]
-        
-        // Add a label for easier debugging
-        query[kSecAttrLabel as String] = "bitchat-\(key)"
-        
-        // For sandboxed apps, use the app group for sharing between app instances
-        if isSandboxed() {
-            query[kSecAttrAccessGroup as String] = appGroup
-        }
-        
-        // For sandboxed macOS apps, we need to ensure the item is NOT synchronized
         #if os(macOS)
-        query[kSecAttrSynchronizable as String] = false
+        base[kSecAttrSynchronizable as String] = false
         #endif
-        
-        let status = SecItemAdd(query as CFDictionary, nil)
-        
-        if status == errSecSuccess {
-            return true
-        } else if status == -34018 {
-            SecureLogger.logError(NSError(domain: "Keychain", code: -34018), context: "Missing keychain entitlement", category: SecureLogger.keychain)
+
+        // Try with access group where it is expected to work (iOS app builds)
+        var triedWithoutGroup = false
+        func attempt(addAccessGroup: Bool) -> OSStatus {
+            var query = base
+            if addAccessGroup { query[kSecAttrAccessGroup as String] = appGroup }
+            return SecItemAdd(query as CFDictionary, nil)
+        }
+
+        #if os(iOS)
+        var status = attempt(addAccessGroup: true)
+        if status == -34018 { // Missing entitlement, retry without access group
+            triedWithoutGroup = true
+            status = attempt(addAccessGroup: false)
+        }
+        #else
+        // On macOS dev/simulator default to no access group to avoid -34018
+        let status = attempt(addAccessGroup: false)
+        #endif
+
+        if status == errSecSuccess { return true }
+        if status == -34018 && !triedWithoutGroup {
+            SecureLogger.error(NSError(domain: "Keychain", code: -34018), context: "Missing keychain entitlement", category: .keychain)
         } else if status != errSecDuplicateItem {
-            SecureLogger.logError(NSError(domain: "Keychain", code: Int(status)), context: "Error saving to keychain", category: SecureLogger.keychain)
+            SecureLogger.error(NSError(domain: "Keychain", code: Int(status)), context: "Error saving to keychain", category: .keychain)
         }
-        
         return false
     }
     
@@ -168,45 +105,56 @@ class KeychainManager {
     }
     
     private func retrieveData(forKey key: String) -> Data? {
-        var query: [String: Any] = [
+        // Base query
+        let base: [String: Any] = [
             kSecClass as String: kSecClassGenericPassword,
             kSecAttrAccount as String: key,
             kSecAttrService as String: service,
             kSecReturnData as String: true,
             kSecMatchLimit as String: kSecMatchLimitOne
         ]
-        
-        // For sandboxed apps, use the app group
-        if isSandboxed() {
-            query[kSecAttrAccessGroup as String] = appGroup
-        }
-        
+
         var result: AnyObject?
-        let status = SecItemCopyMatching(query as CFDictionary, &result)
-        
-        if status == errSecSuccess {
-            return result as? Data
-        } else if status == -34018 {
-            SecureLogger.logError(NSError(domain: "Keychain", code: -34018), context: "Missing keychain entitlement", category: SecureLogger.keychain)
+        func attempt(withAccessGroup: Bool) -> OSStatus {
+            var q = base
+            if withAccessGroup { q[kSecAttrAccessGroup as String] = appGroup }
+            return SecItemCopyMatching(q as CFDictionary, &result)
+        }
+
+        #if os(iOS)
+        var status = attempt(withAccessGroup: true)
+        if status == -34018 { status = attempt(withAccessGroup: false) }
+        #else
+        let status = attempt(withAccessGroup: false)
+        #endif
+
+        if status == errSecSuccess { return result as? Data }
+        if status == -34018 {
+            SecureLogger.error(NSError(domain: "Keychain", code: -34018), context: "Missing keychain entitlement", category: .keychain)
         }
-        
         return nil
     }
     
     private func delete(forKey key: String) -> Bool {
-        // Build basic query
-        var query: [String: Any] = [
+        // Base delete query
+        let base: [String: Any] = [
             kSecClass as String: kSecClassGenericPassword,
             kSecAttrAccount as String: key,
             kSecAttrService as String: service
         ]
-        
-        // For sandboxed apps, use the app group
-        if isSandboxed() {
-            query[kSecAttrAccessGroup as String] = appGroup
+
+        func attempt(withAccessGroup: Bool) -> OSStatus {
+            var q = base
+            if withAccessGroup { q[kSecAttrAccessGroup as String] = appGroup }
+            return SecItemDelete(q as CFDictionary)
         }
-        
-        let status = SecItemDelete(query as CFDictionary)
+
+        #if os(iOS)
+        var status = attempt(withAccessGroup: true)
+        if status == -34018 { status = attempt(withAccessGroup: false) }
+        #else
+        let status = attempt(withAccessGroup: false)
+        #endif
         return status == errSecSuccess || status == errSecItemNotFound
     }
     
@@ -226,15 +174,10 @@ class KeychainManager {
         return status == errSecSuccess || status == errSecItemNotFound
     }
     
-    // Force cleanup to run again (for development/testing)
-    func resetCleanupFlag() {
-        UserDefaults.standard.removeObject(forKey: "bitchat.keychain.cleanup.v2")
-    }
-    
     
     // Delete ALL keychain data for panic mode
     func deleteAllKeychainData() -> Bool {
-        SecureLogger.log("Panic mode - deleting all keychain data", category: SecureLogger.security, level: .warning)
+        SecureLogger.warning("Panic mode - deleting all keychain data", category: .security)
         
         var totalDeleted = 0
         
@@ -253,10 +196,25 @@ class KeychainManager {
                 var shouldDelete = false
                 let account = item[kSecAttrAccount as String] as? String ?? ""
                 let service = item[kSecAttrService as String] as? String ?? ""
+                let accessGroup = item[kSecAttrAccessGroup as String] as? String
                 
-                // ONLY delete if service name contains "bitchat"
-                // This is the safest approach - we only touch items we know are ours
-                if service.lowercased().contains("bitchat") {
+                // More precise deletion criteria:
+                // 1. Check for our specific app group
+                // 2. OR check for our exact service name
+                // 3. OR check for known legacy service names
+                if accessGroup == appGroup {
+                    shouldDelete = true
+                } else if service == self.service {
+                    shouldDelete = true
+                } else if [
+                    "com.bitchat.passwords",
+                    "com.bitchat.deviceidentity",
+                    "com.bitchat.noise.identity",
+                    "chat.bitchat.passwords",
+                    "bitchat.keychain",
+                    "bitchat",
+                    "com.bitchat"
+                ].contains(service) {
                     shouldDelete = true
                 }
                 
@@ -282,19 +240,21 @@ class KeychainManager {
                     let deleteStatus = SecItemDelete(deleteQuery as CFDictionary)
                     if deleteStatus == errSecSuccess {
                         totalDeleted += 1
-                        SecureLogger.log("Deleted keychain item: \(account) from \(service)", category: SecureLogger.keychain, level: .info)
+                        SecureLogger.info("Deleted keychain item: \(account) from \(service)", category: .keychain)
                     }
                 }
             }
         }
         
-        // Also try to delete by known service names (in case we missed any)
+        // Also try to delete by known service names and app group
+        // This catches any items that might have been missed above
         let knownServices = [
-            "chat.bitchat",
+            self.service,  // Current service name
             "com.bitchat.passwords",
             "com.bitchat.deviceidentity", 
             "com.bitchat.noise.identity",
             "chat.bitchat.passwords",
+            "chat.bitchat.nostr",
             "bitchat.keychain",
             "bitchat",
             "com.bitchat"
@@ -312,87 +272,46 @@ class KeychainManager {
             }
         }
         
-        SecureLogger.log("Panic mode cleanup completed. Total items deleted: \(totalDeleted)", category: SecureLogger.keychain, level: .warning)
+        // Also delete by app group to ensure complete cleanup
+        let groupQuery: [String: Any] = [
+            kSecClass as String: kSecClassGenericPassword,
+            kSecAttrAccessGroup as String: appGroup
+        ]
+        
+        let groupStatus = SecItemDelete(groupQuery as CFDictionary)
+        if groupStatus == errSecSuccess {
+            totalDeleted += 1
+        }
+        
+        SecureLogger.warning("Panic mode cleanup completed. Total items deleted: \(totalDeleted)", category: .keychain)
         
         return totalDeleted > 0
     }
     
+    // MARK: - Security Utilities
+    
+    /// Securely clear sensitive data from memory
+    func secureClear(_ data: inout Data) {
+        _ = data.withUnsafeMutableBytes { bytes in
+            // Use volatile memset to prevent compiler optimization
+            memset_s(bytes.baseAddress, bytes.count, 0, bytes.count)
+        }
+        data = Data() // Clear the data object
+    }
+    
+    /// Securely clear sensitive string from memory
+    func secureClear(_ string: inout String) {
+        // Convert to mutable data and clear
+        if var data = string.data(using: .utf8) {
+            secureClear(&data)
+        }
+        string = "" // Clear the string object
+    }
+    
     // MARK: - Debug
     
     func verifyIdentityKeyExists() -> Bool {
         let key = "identity_noiseStaticKey"
         return retrieveData(forKey: key) != nil
     }
-    
-    // Aggressive cleanup for legacy items - can be called manually
-    func aggressiveCleanupLegacyItems() -> Int {
-        var deletedCount = 0
-        
-        // List of KNOWN bitchat service names from our development history
-        let knownBitchatServices = [
-            "com.bitchat.passwords",
-            "com.bitchat.deviceidentity",
-            "com.bitchat.noise.identity",
-            "chat.bitchat.passwords",
-            "bitchat.keychain",
-            "Bitchat",
-            "BitChat"
-        ]
-        
-        // First, delete all items from known legacy services
-        for legacyService in knownBitchatServices {
-            let deleteQuery: [String: Any] = [
-                kSecClass as String: kSecClassGenericPassword,
-                kSecAttrService as String: legacyService
-            ]
-            
-            let status = SecItemDelete(deleteQuery as CFDictionary)
-            if status == errSecSuccess {
-                deletedCount += 1
-            }
-        }
-        
-        // Now search for items that have our specific account patterns with bitchat service names
-        let searchQuery: [String: Any] = [
-            kSecClass as String: kSecClassGenericPassword,
-            kSecMatchLimit as String: kSecMatchLimitAll,
-            kSecReturnAttributes as String: true
-        ]
-        
-        var result: AnyObject?
-        let status = SecItemCopyMatching(searchQuery as CFDictionary, &result)
-        
-        if status == errSecSuccess, let items = result as? [[String: Any]] {
-            for item in items {
-                let account = item[kSecAttrAccount as String] as? String ?? ""
-                let service = item[kSecAttrService as String] as? String ?? ""
-                
-                // ONLY delete if service name contains "bitchat" somewhere
-                // This ensures we never touch other apps' keychain items
-                var shouldDelete = false
-                
-                // Check if service contains "bitchat" (case insensitive) but NOT our current service
-                let serviceLower = service.lowercased()
-                if service != self.service && serviceLower.contains("bitchat") {
-                    shouldDelete = true
-                }
-                
-                if shouldDelete {
-                    // Build precise delete query
-                    let deleteQuery: [String: Any] = [
-                        kSecClass as String: kSecClassGenericPassword,
-                        kSecAttrService as String: service,
-                        kSecAttrAccount as String: account
-                    ]
-                    
-                    let deleteStatus = SecItemDelete(deleteQuery as CFDictionary)
-                    if deleteStatus == errSecSuccess {
-                        deletedCount += 1
-                    }
-                }
-            }
-        }
-        
-        return deletedCount
-    }
-}
+}

bitchat/Services/LocationChannelManager.swift

@@ -0,0 +1,306 @@
+import BitLogger
+import Foundation
+import Combine
+
+#if os(iOS) || os(macOS)
+import CoreLocation
+
+/// Manages location permissions, one-shot location retrieval, and computing geohash channels.
+/// Not main-actor isolated to satisfy CLLocationManagerDelegate in Swift 6; state updates hop to MainActor.
+final class LocationChannelManager: NSObject, CLLocationManagerDelegate, ObservableObject {
+    static let shared = LocationChannelManager()
+
+    enum PermissionState: Equatable {
+        case notDetermined
+        case denied
+        case restricted
+        case authorized
+    }
+
+    private let cl = CLLocationManager()
+    private let geocoder = CLGeocoder()
+    private var lastLocation: CLLocation?
+    private var refreshTimer: Timer?
+    private let userDefaultsKey = "locationChannel.selected"
+    private let teleportedStoreKey = "locationChannel.teleportedSet"
+    private var isGeocoding: Bool = false
+
+    // Published state for UI bindings
+    @Published private(set) var permissionState: PermissionState = .notDetermined
+    @Published private(set) var availableChannels: [GeohashChannel] = []
+    @Published private(set) var selectedChannel: ChannelID = .mesh
+    // True when the current location channel was selected via manual teleport
+    @Published var teleported: Bool = false
+    @Published private(set) var locationNames: [GeohashChannelLevel: String] = [:]
+
+    // Persisted set of geohashes that were selected via teleport
+    private var teleportedSet: Set<String> = []
+
+    private override init() {
+        super.init()
+        cl.delegate = self
+        cl.desiredAccuracy = kCLLocationAccuracyHundredMeters
+        cl.distanceFilter = TransportConfig.locationDistanceFilterMeters // meters; we're not tracking continuously
+        // Load selection
+        if let data = UserDefaults.standard.data(forKey: userDefaultsKey),
+           let channel = try? JSONDecoder().decode(ChannelID.self, from: data) {
+            selectedChannel = channel
+        }
+        // Load persisted teleported set
+        if let data = UserDefaults.standard.data(forKey: teleportedStoreKey),
+           let arr = try? JSONDecoder().decode([String].self, from: data) {
+            teleportedSet = Set(arr)
+        }
+        // Do not eagerly mark teleported on startup; wait for location to compute regional set.
+        // This avoids showing teleported for in-region channels during cold start.
+        let status: CLAuthorizationStatus
+        if #available(iOS 14.0, macOS 11.0, *) {
+            status = cl.authorizationStatus
+        } else {
+            status = CLLocationManager.authorizationStatus()
+        }
+        updatePermissionState(from: status)
+        // If we don't have location authorization at startup, fall back to persisted teleport state
+        switch status {
+        case .authorizedAlways, .authorizedWhenInUse, .authorized:
+            break // will compute from location
+        case .notDetermined, .restricted, .denied:
+            fallthrough
+        @unknown default:
+            if case .location(let ch) = selectedChannel {
+                teleported = teleportedSet.contains(ch.geohash)
+            }
+        }
+    }
+
+    // MARK: - Public API
+    func enableLocationChannels() {
+        let status: CLAuthorizationStatus
+        if #available(iOS 14.0, macOS 11.0, *) {
+            status = cl.authorizationStatus
+        } else {
+            status = CLLocationManager.authorizationStatus()
+        }
+        switch status {
+        case .notDetermined:
+            cl.requestWhenInUseAuthorization()
+        case .restricted:
+            Task { @MainActor in self.permissionState = .restricted }
+        case .denied:
+            Task { @MainActor in self.permissionState = .denied }
+        case .authorizedAlways, .authorizedWhenInUse, .authorized:
+            Task { @MainActor in self.permissionState = .authorized }
+            requestOneShotLocation()
+        @unknown default:
+            Task { @MainActor in self.permissionState = .restricted }
+        }
+    }
+
+    func refreshChannels() {
+        if permissionState == .authorized {
+            requestOneShotLocation()
+        }
+    }
+
+    /// Begin continuous, distance-filtered updates while the channel sheet is visible.
+    /// Uses a 21m filter (configurable) to only refresh on meaningful movement.
+    func beginLiveRefresh(interval: TimeInterval = TransportConfig.locationLiveRefreshInterval) {
+        guard permissionState == .authorized else { return }
+        // Stop any previous polling timer
+        refreshTimer?.invalidate()
+        refreshTimer = nil
+        // Tighten accuracy and distance filter for live view
+        cl.desiredAccuracy = kCLLocationAccuracyNearestTenMeters
+        cl.distanceFilter = TransportConfig.locationDistanceFilterLiveMeters
+        // Start continuous updates
+        cl.startUpdatingLocation()
+        // Request an immediate fix to populate UI without waiting for movement
+        requestOneShotLocation()
+    }
+
+    /// Stop continuous refreshes when selector UI is dismissed.
+    func endLiveRefresh() {
+        refreshTimer?.invalidate()
+        refreshTimer = nil
+        cl.stopUpdatingLocation()
+        // Restore more relaxed defaults for background/idle state
+        cl.desiredAccuracy = kCLLocationAccuracyHundredMeters
+        cl.distanceFilter = TransportConfig.locationDistanceFilterMeters
+    }
+
+    func select(_ channel: ChannelID) {
+        Task { @MainActor in
+            self.selectedChannel = channel
+            if let data = try? JSONEncoder().encode(channel) {
+                UserDefaults.standard.set(data, forKey: self.userDefaultsKey)
+            }
+            // Update teleported flag based on persisted state for immediate UI behavior
+            switch channel {
+            case .mesh:
+                self.teleported = false
+            case .location(let ch):
+                // If this geohash is in our current regional set, do NOT mark teleported.
+                let inRegional = self.availableChannels.contains { $0.geohash == ch.geohash }
+                if inRegional {
+                    self.teleported = false
+                    // Clear persisted teleport for this geohash to keep future selections clean
+                    if self.teleportedSet.contains(ch.geohash) {
+                        self.teleportedSet.remove(ch.geohash)
+                        if let data = try? JSONEncoder().encode(Array(self.teleportedSet)) {
+                            UserDefaults.standard.set(data, forKey: self.teleportedStoreKey)
+                        }
+                    }
+                } else {
+                    // Fall back to persisted mark (set by deep link or manual teleport)
+                    self.teleported = self.teleportedSet.contains(ch.geohash)
+                }
+            }
+        }
+    }
+
+    // Mark or unmark a geohash as teleported in persistence and update current flag if relevant
+    func markTeleported(for geohash: String, _ flag: Bool) {
+        if flag { teleportedSet.insert(geohash) } else { teleportedSet.remove(geohash) }
+        if let data = try? JSONEncoder().encode(Array(teleportedSet)) {
+            UserDefaults.standard.set(data, forKey: teleportedStoreKey)
+        }
+        if case .location(let ch) = selectedChannel, ch.geohash == geohash {
+            Task { @MainActor in self.teleported = flag }
+        }
+    }
+
+    // MARK: - CoreLocation
+    private func requestOneShotLocation() {
+        cl.requestLocation()
+    }
+
+    // iOS < 14
+    func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
+        updatePermissionState(from: status)
+        if case .authorized = permissionState {
+            requestOneShotLocation()
+        }
+    }
+
+    // iOS 14+ / macOS 11+
+    @available(iOS 14.0, macOS 11.0, *)
+    func locationManagerDidChangeAuthorization(_ manager: CLLocationManager) {
+        updatePermissionState(from: manager.authorizationStatus)
+        if case .authorized = permissionState {
+            requestOneShotLocation()
+        }
+    }
+
+    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
+        guard let loc = locations.last else { return }
+        lastLocation = loc
+        computeChannels(from: loc.coordinate)
+        reverseGeocodeIfNeeded(location: loc)
+    }
+
+    func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
+        // Surface as denied/restricted if relevant; otherwise keep previous state
+        SecureLogger.error("LocationChannelManager: location error: \(error.localizedDescription)", category: .session)
+    }
+
+    // MARK: - Helpers
+    private func updatePermissionState(from status: CLAuthorizationStatus) {
+        let newState: PermissionState
+        switch status {
+        case .notDetermined: newState = .notDetermined
+        case .restricted: newState = .restricted
+        case .denied: newState = .denied
+        case .authorizedAlways, .authorizedWhenInUse, .authorized: newState = .authorized
+        @unknown default: newState = .restricted
+        }
+        Task { @MainActor in self.permissionState = newState }
+    }
+
+    private func computeChannels(from coord: CLLocationCoordinate2D) {
+        let levels = GeohashChannelLevel.allCases
+        var result: [GeohashChannel] = []
+        for level in levels {
+            let gh = Geohash.encode(latitude: coord.latitude, longitude: coord.longitude, precision: level.precision)
+            result.append(GeohashChannel(level: level, geohash: gh))
+        }
+        Task { @MainActor in
+            self.availableChannels = result
+            // Recompute teleported status based on whether the selected geohash is in our regional set
+            switch self.selectedChannel {
+            case .mesh:
+                self.teleported = false
+            case .location(let ch):
+                // Membership check using freshly computed regional channels; avoids precision/rename drift
+                let inRegional = result.contains { $0.geohash == ch.geohash }
+                if inRegional {
+                    self.teleported = false
+                    // Clear persisted teleport flag if present
+                    if self.teleportedSet.contains(ch.geohash) {
+                        self.teleportedSet.remove(ch.geohash)
+                        if let data = try? JSONEncoder().encode(Array(self.teleportedSet)) {
+                            UserDefaults.standard.set(data, forKey: self.teleportedStoreKey)
+                        }
+                    }
+                } else {
+                    self.teleported = true
+                }
+            }
+        }
+    }
+
+    private func reverseGeocodeIfNeeded(location: CLLocation) {
+        // Always cancel previous to keep latest fresh while user moves
+        geocoder.cancelGeocode()
+        isGeocoding = true
+        geocoder.reverseGeocodeLocation(location) { [weak self] placemarks, error in
+            guard let self = self else { return }
+            self.isGeocoding = false
+            if let pm = placemarks?.first {
+                let names = self.namesByLevel(from: pm)
+                Task { @MainActor in self.locationNames = names }
+            }
+        }
+    }
+
+    private func namesByLevel(from pm: CLPlacemark) -> [GeohashChannelLevel: String] {
+        var dict: [GeohashChannelLevel: String] = [:]
+        // Region (country)
+        if let country = pm.country, !country.isEmpty {
+            dict[.region] = country
+        }
+        // Province (state/province or county)
+        if let admin = pm.administrativeArea, !admin.isEmpty {
+            dict[.province] = admin
+        } else if let subAdmin = pm.subAdministrativeArea, !subAdmin.isEmpty {
+            dict[.province] = subAdmin
+        }
+        // City (locality)
+        if let locality = pm.locality, !locality.isEmpty {
+            dict[.city] = locality
+        } else if let subAdmin = pm.subAdministrativeArea, !subAdmin.isEmpty {
+            dict[.city] = subAdmin
+        } else if let admin = pm.administrativeArea, !admin.isEmpty {
+            dict[.city] = admin
+        }
+        // Neighborhood
+        if let subLocality = pm.subLocality, !subLocality.isEmpty {
+            dict[.neighborhood] = subLocality
+        } else if let locality = pm.locality, !locality.isEmpty {
+            dict[.neighborhood] = locality
+        }
+        // Block: reuse neighborhood/locality granularity
+        if let subLocality = pm.subLocality, !subLocality.isEmpty {
+            dict[.block] = subLocality
+        } else if let locality = pm.locality, !locality.isEmpty {
+            dict[.block] = locality
+        }
+        // Building: prefer place name/street/venue when available
+        if let name = pm.name, !name.isEmpty {
+            dict[.building] = name
+        } else if let thoroughfare = pm.thoroughfare, !thoroughfare.isEmpty {
+            dict[.building] = thoroughfare
+        }
+        return dict
+    }
+}
+#endif

bitchat/Services/LocationNotesManager.swift

@@ -0,0 +1,257 @@
+import BitLogger
+import Foundation
+
+/// Dependencies for location notes, allowing tests to stub relay/identity behavior.
+struct LocationNotesDependencies {
+    typealias RelayLookup = @MainActor (_ geohash: String, _ count: Int) -> [String]
+    typealias Subscribe = @MainActor (_ filter: NostrFilter, _ id: String, _ relays: [String], _ handler: @escaping (NostrEvent) -> Void, _ onEOSE: (() -> Void)?) -> Void
+    typealias Unsubscribe = @MainActor (_ id: String) -> Void
+    typealias SendEvent = @MainActor (_ event: NostrEvent, _ relayUrls: [String]) -> Void
+
+    var relayLookup: RelayLookup
+    var subscribe: Subscribe
+    var unsubscribe: Unsubscribe
+    var sendEvent: SendEvent
+    var deriveIdentity: (_ geohash: String) throws -> NostrIdentity
+    var now: () -> Date
+    
+    private static let idBridge = NostrIdentityBridge()
+
+    static let live = LocationNotesDependencies(
+        relayLookup: { geohash, count in
+            GeoRelayDirectory.shared.closestRelays(toGeohash: geohash, count: count)
+        },
+        subscribe: { filter, id, relays, handler, onEOSE in
+            NostrRelayManager.shared.subscribe(
+                filter: filter,
+                id: id,
+                relayUrls: relays,
+                handler: handler,
+                onEOSE: onEOSE
+            )
+        },
+        unsubscribe: { id in
+            NostrRelayManager.shared.unsubscribe(id: id)
+        },
+        sendEvent: { event, relays in
+            NostrRelayManager.shared.sendEvent(event, to: relays)
+        },
+        deriveIdentity: { geohash in
+            try idBridge.deriveIdentity(forGeohash: geohash)
+        },
+        now: { Date() }
+    )
+}
+
+/// Persistent location notes (Nostr kind 1) scoped to a building-level geohash (precision 8).
+/// Subscribes to and publishes notes for a given geohash and provides a send API.
+@MainActor
+final class LocationNotesManager: ObservableObject {
+    enum State: Equatable {
+        case idle
+        case loading
+        case ready
+        case noRelays
+    }
+
+    struct Note: Identifiable, Equatable {
+        let id: String
+        let pubkey: String
+        let content: String
+        let createdAt: Date
+        let nickname: String?
+
+        var displayName: String {
+            let suffix = String(pubkey.suffix(4))
+            if let nick = nickname, !nick.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty {
+                return "\(nick)#\(suffix)"
+            }
+            return "anon#\(suffix)"
+        }
+    }
+
+    @Published private(set) var notes: [Note] = [] // reverse-chron sorted
+    @Published private(set) var geohash: String
+    @Published private(set) var initialLoadComplete: Bool = false
+    @Published private(set) var state: State = .loading
+    @Published private(set) var errorMessage: String?
+    private var subscriptionID: String?
+    private var noteIDs = Set<String>() // O(1) duplicate detection
+    private let dependencies: LocationNotesDependencies
+    private let maxNotesInMemory = 500 // Defensive cap (relay limit is 200)
+
+    private enum Strings {
+        static let noRelays = String(localized: "location_notes.error.no_relays", comment: "Shown when no geo relays are available near the selected location")
+
+        static func failedToSend(_ detail: String) -> String {
+            String(
+                format: String(localized: "location_notes.error.failed_to_send", comment: "Shown when a location note fails to send"),
+                locale: .current,
+                detail
+            )
+        }
+    }
+
+    init(geohash: String, dependencies: LocationNotesDependencies = .live) {
+        let norm = geohash.lowercased()
+        self.geohash = norm
+        self.dependencies = dependencies
+        // Validate geohash (building-level precision: 8 chars)
+        if !Geohash.isValidBuildingGeohash(norm) {
+            SecureLogger.warning("LocationNotesManager: invalid geohash '\(norm)' (expected 8 valid base32 chars)", category: .session)
+        }
+        subscribe()
+    }
+
+    func setGeohash(_ newGeohash: String) {
+        let norm = newGeohash.lowercased()
+        guard norm != geohash else { return }
+        // Validate geohash (building-level precision: 8 chars)
+        guard Geohash.isValidBuildingGeohash(norm) else {
+            SecureLogger.warning("LocationNotesManager: rejecting invalid geohash '\(norm)' (expected 8 valid base32 chars)", category: .session)
+            return
+        }
+        if let sub = subscriptionID {
+            dependencies.unsubscribe(sub)
+            subscriptionID = nil
+        }
+        // Set loading state before clearing to prevent empty state flicker
+        state = .loading
+        initialLoadComplete = false
+        errorMessage = nil
+        geohash = norm
+        notes.removeAll()
+        noteIDs.removeAll()
+        subscribe()
+    }
+
+    func refresh() {
+        if let sub = subscriptionID {
+            dependencies.unsubscribe(sub)
+            subscriptionID = nil
+        }
+        // Set loading state before clearing to prevent empty state flicker
+        state = .loading
+        initialLoadComplete = false
+        errorMessage = nil
+        notes.removeAll()
+        noteIDs.removeAll()
+        subscribe()
+    }
+
+    func clearError() {
+        errorMessage = nil
+    }
+
+    private func subscribe() {
+        state = .loading
+        errorMessage = nil
+        if let sub = subscriptionID {
+            dependencies.unsubscribe(sub)
+            subscriptionID = nil
+        }
+        let subID = "locnotes-\(geohash)-\(UUID().uuidString.prefix(8))"
+        let relays = dependencies.relayLookup(geohash, TransportConfig.nostrGeoRelayCount)
+        guard !relays.isEmpty else {
+            subscriptionID = nil
+            initialLoadComplete = true
+            state = .noRelays
+            errorMessage = Strings.noRelays
+            SecureLogger.warning("LocationNotesManager: no geo relays for geohash=\(geohash)", category: .session)
+            return
+        }
+
+        subscriptionID = subID
+        initialLoadComplete = false
+
+        // Subscribe to center + 8 neighbors (± 1 grid)
+        let neighbors = Geohash.neighbors(of: geohash)
+        let allGeohashes = [geohash] + neighbors
+        let filter = NostrFilter.geohashNotes(allGeohashes, since: nil, limit: 200)
+
+        // Build a set of valid geohashes for tag matching (includes all 9 cells)
+        let validGeohashes = Set(allGeohashes.map { $0.lowercased() })
+
+        dependencies.subscribe(filter, subID, relays, { [weak self] event in
+            guard let self = self else { return }
+            guard event.kind == NostrProtocol.EventKind.textNote.rawValue else { return }
+            // Ensure matching tag - accept any of our 9 geohashes
+            guard event.tags.contains(where: { tag in
+                tag.count >= 2 && tag[0].lowercased() == "g" && validGeohashes.contains(tag[1].lowercased())
+            }) else { return }
+            guard !self.noteIDs.contains(event.id) else { return }
+            self.noteIDs.insert(event.id)
+            let nick = event.tags.first(where: { $0.first?.lowercased() == "n" && $0.count >= 2 })?.dropFirst().first
+            let ts = Date(timeIntervalSince1970: TimeInterval(event.created_at))
+            let note = Note(id: event.id, pubkey: event.pubkey, content: event.content, createdAt: ts, nickname: nick)
+            self.notes.append(note)
+            self.notes.sort { $0.createdAt > $1.createdAt }
+            self.enforceMemoryCap()
+            self.state = .ready
+        }, { [weak self] in
+            guard let self = self else { return }
+            self.initialLoadComplete = true
+            if self.state != .noRelays {
+                self.state = .ready
+            }
+        })
+    }
+
+    /// Send a location note for the current geohash using the per-geohash identity.
+    func send(content: String, nickname: String) {
+        let trimmed = content.trimmingCharacters(in: .whitespacesAndNewlines)
+        guard !trimmed.isEmpty else { return }
+        let relays = dependencies.relayLookup(geohash, TransportConfig.nostrGeoRelayCount)
+        guard !relays.isEmpty else {
+            state = .noRelays
+            errorMessage = Strings.noRelays
+            SecureLogger.warning("LocationNotesManager: send blocked, no geo relays for geohash=\(geohash)", category: .session)
+            return
+        }
+        do {
+            let id = try dependencies.deriveIdentity(geohash)
+            let event = try NostrProtocol.createGeohashTextNote(
+                content: trimmed,
+                geohash: geohash,
+                senderIdentity: id,
+                nickname: nickname
+            )
+            dependencies.sendEvent(event, relays)
+            // Optimistic local-echo
+            let echo = Note(
+                id: event.id,
+                pubkey: id.publicKeyHex,
+                content: trimmed,
+                createdAt: Date(timeIntervalSince1970: TimeInterval(event.created_at)),
+                nickname: nickname
+            )
+            self.noteIDs.insert(event.id)
+            self.notes.insert(echo, at: 0)
+            self.enforceMemoryCap()
+            self.state = .ready
+            self.errorMessage = nil
+        } catch {
+            SecureLogger.error("LocationNotesManager: failed to send note: \(error)", category: .session)
+            errorMessage = Strings.failedToSend(error.localizedDescription)
+        }
+    }
+
+    /// Enforces defensive memory cap on notes array (keeps newest).
+    private func enforceMemoryCap() {
+        if notes.count > maxNotesInMemory {
+            let removed = notes.count - maxNotesInMemory
+            notes = Array(notes.prefix(maxNotesInMemory))
+            SecureLogger.debug("LocationNotesManager: trimmed \(removed) old notes (cap: \(maxNotesInMemory))", category: .session)
+        }
+    }
+
+    /// Explicitly cancel subscription and release resources.
+    func cancel() {
+        if let sub = subscriptionID {
+            dependencies.unsubscribe(sub)
+            subscriptionID = nil
+        }
+        state = .idle
+        errorMessage = nil
+    }
+}

bitchat/Services/MeshTopologyTracker.swift

@@ -0,0 +1,120 @@
+import Foundation
+
+/// Tracks observed mesh topology and computes hop-by-hop routes.
+final class MeshTopologyTracker {
+    private typealias RoutingID = Data
+
+    private let queue = DispatchQueue(label: "mesh.topology", attributes: .concurrent)
+    private let hopSize = 8
+    private var adjacency: [RoutingID: Set<RoutingID>] = [:]
+
+    func reset() {
+        queue.sync(flags: .barrier) {
+            self.adjacency.removeAll()
+        }
+    }
+
+    func recordDirectLink(between a: Data?, and b: Data?) {
+        guard let left = sanitize(a), let right = sanitize(b), left != right else { return }
+        queue.sync(flags: .barrier) {
+            var setA = self.adjacency[left] ?? []
+            setA.insert(right)
+            self.adjacency[left] = setA
+
+            var setB = self.adjacency[right] ?? []
+            setB.insert(left)
+            self.adjacency[right] = setB
+        }
+    }
+
+    func removeDirectLink(between a: Data?, and b: Data?) {
+        guard let left = sanitize(a), let right = sanitize(b), left != right else { return }
+        queue.sync(flags: .barrier) {
+            if var setA = self.adjacency[left] {
+                setA.remove(right)
+                self.adjacency[left] = setA.isEmpty ? nil : setA
+            }
+            if var setB = self.adjacency[right] {
+                setB.remove(left)
+                self.adjacency[right] = setB.isEmpty ? nil : setB
+            }
+        }
+    }
+
+    func removePeer(_ data: Data?) {
+        guard let peer = sanitize(data) else { return }
+        queue.sync(flags: .barrier) {
+            guard let neighbors = self.adjacency.removeValue(forKey: peer) else { return }
+            for neighbor in neighbors {
+                if var set = self.adjacency[neighbor] {
+                    set.remove(peer)
+                    self.adjacency[neighbor] = set.isEmpty ? nil : set
+                }
+            }
+        }
+    }
+
+    func recordRoute(_ hops: [Data]) {
+        let sanitized = hops.compactMap { sanitize($0) }
+        guard sanitized.count >= 2 else { return }
+        queue.sync(flags: .barrier) {
+            for idx in 0..<(sanitized.count - 1) {
+                let left = sanitized[idx]
+                let right = sanitized[idx + 1]
+                guard left != right else { continue }
+
+                var setA = self.adjacency[left] ?? []
+                setA.insert(right)
+                self.adjacency[left] = setA
+
+                var setB = self.adjacency[right] ?? []
+                setB.insert(left)
+                self.adjacency[right] = setB
+            }
+        }
+    }
+
+    func computeRoute(from start: Data?, to goal: Data?, maxHops: Int = 255) -> [Data]? {
+        guard let source = sanitize(start), let target = sanitize(goal) else { return nil }
+        if source == target { return [source] }
+
+        let graph = queue.sync { adjacency }
+        guard graph[source] != nil, graph[target] != nil else { return nil }
+
+        var visited: Set<RoutingID> = [source]
+        var queuePaths: [[RoutingID]] = [[source]]
+        var index = 0
+
+        while index < queuePaths.count {
+            let path = queuePaths[index]
+            index += 1
+            guard path.count <= maxHops else { continue }
+            guard let last = path.last, let neighbors = graph[last] else { continue }
+
+            for neighbor in neighbors {
+                if visited.contains(neighbor) { continue }
+                var nextPath = path
+                nextPath.append(neighbor)
+                if neighbor == target { return nextPath }
+                if nextPath.count <= maxHops {
+                    queuePaths.append(nextPath)
+                }
+                visited.insert(neighbor)
+            }
+        }
+
+        return nil
+    }
+
+    // MARK: - Helpers
+
+    private func sanitize(_ data: Data?) -> Data? {
+        guard var value = data, !value.isEmpty else { return nil }
+        if value.count > hopSize {
+            value = Data(value.prefix(hopSize))
+        } else if value.count < hopSize {
+            value.append(Data(repeating: 0, count: hopSize - value.count))
+        }
+        return value
+    }
+}

bitchat/Services/MessageRetryService.swift

@@ -1,212 +0,0 @@
-//
-// MessageRetryService.swift
-// bitchat
-//
-// This is free and unencumbered software released into the public domain.
-// For more information, see <https://unlicense.org>
-//
-
-import Foundation
-import Combine
-import CryptoKit
-
-struct RetryableMessage {
-    let id: String
-    let originalMessageID: String? 
-    let originalTimestamp: Date?
-    let content: String
-    let mentions: [String]?
-    let isPrivate: Bool
-    let recipientPeerID: String?
-    let recipientNickname: String?
-    let retryCount: Int
-    let maxRetries: Int = 3
-    let nextRetryTime: Date
-}
-
-class MessageRetryService {
-    static let shared = MessageRetryService()
-    
-    private var retryQueue: [RetryableMessage] = []
-    private var retryTimer: Timer?
-    private let retryInterval: TimeInterval = 2.0 // Retry every 2 seconds for faster sync
-    private let maxQueueSize = 50
-    
-    weak var meshService: BluetoothMeshService?
-    
-    private init() {
-        startRetryTimer()
-    }
-    
-    deinit {
-        retryTimer?.invalidate()
-    }
-    
-    private func startRetryTimer() {
-        retryTimer = Timer.scheduledTimer(withTimeInterval: retryInterval, repeats: true) { [weak self] _ in
-            self?.processRetryQueue()
-        }
-    }
-    
-    func addMessageForRetry(
-        content: String,
-        mentions: [String]? = nil,
-        isPrivate: Bool = false,
-        recipientPeerID: String? = nil,
-        recipientNickname: String? = nil,
-        originalMessageID: String? = nil,
-        originalTimestamp: Date? = nil
-    ) {
-        // Don't queue empty or whitespace-only messages
-        guard !content.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty else {
-            return
-        }
-        
-        // Don't queue if we're at capacity
-        guard retryQueue.count < maxQueueSize else {
-            return
-        }
-        
-        // Check if this message is already in the queue
-        if let messageID = originalMessageID {
-            let alreadyQueued = retryQueue.contains { msg in
-                msg.originalMessageID == messageID
-            }
-            if alreadyQueued {
-                return // Don't add duplicate
-            }
-        }
-        
-        let retryMessage = RetryableMessage(
-            id: UUID().uuidString,
-            originalMessageID: originalMessageID,
-            originalTimestamp: originalTimestamp,
-            content: content,
-            mentions: mentions,
-            isPrivate: isPrivate,
-            recipientPeerID: recipientPeerID,
-            recipientNickname: recipientNickname,
-            retryCount: 0,
-            nextRetryTime: Date().addingTimeInterval(retryInterval)
-        )
-        
-        retryQueue.append(retryMessage)
-        
-        // Sort the queue by original timestamp to maintain message order
-        retryQueue.sort { (msg1, msg2) in
-            let time1 = msg1.originalTimestamp ?? Date.distantPast
-            let time2 = msg2.originalTimestamp ?? Date.distantPast
-            return time1 < time2
-        }
-    }
-    
-    private func processRetryQueue() {
-        guard meshService != nil else { return }
-        
-        let now = Date()
-        var messagesToRetry: [RetryableMessage] = []
-        var updatedQueue: [RetryableMessage] = []
-        
-        for message in retryQueue {
-            if message.nextRetryTime <= now {
-                messagesToRetry.append(message)
-            } else {
-                updatedQueue.append(message)
-            }
-        }
-        
-        retryQueue = updatedQueue
-        
-        // Sort messages by original timestamp to maintain order
-        messagesToRetry.sort { (msg1, msg2) in
-            let time1 = msg1.originalTimestamp ?? Date.distantPast
-            let time2 = msg2.originalTimestamp ?? Date.distantPast
-            return time1 < time2
-        }
-        
-        // Send messages with delay to maintain order
-        for (index, message) in messagesToRetry.enumerated() {
-            // Check if we should still retry
-            if message.retryCount >= message.maxRetries {
-                continue
-            }
-            
-            // Add delay between messages to ensure proper ordering
-            let delay = Double(index) * 0.05 // 50ms between messages
-            
-            DispatchQueue.main.asyncAfter(deadline: .now() + delay) { [weak self] in
-                guard let self = self,
-                      let meshService = self.meshService else { return }
-                
-                // Check connectivity before retrying
-                let viewModel = meshService.delegate as? ChatViewModel
-                let connectedPeers = viewModel?.connectedPeers ?? []
-                
-                if message.isPrivate {
-                    // For private messages, check if recipient is connected
-                    if let recipientID = message.recipientPeerID,
-                       connectedPeers.contains(recipientID) {
-                        // Retry private message
-                        meshService.sendPrivateMessage(
-                            message.content,
-                            to: recipientID,
-                            recipientNickname: message.recipientNickname ?? "unknown",
-                            messageID: message.originalMessageID
-                        )
-                    } else {
-                        // Recipient not connected, keep in queue with updated retry time
-                        var updatedMessage = message
-                        updatedMessage = RetryableMessage(
-                            id: message.id,
-                            originalMessageID: message.originalMessageID,
-                            originalTimestamp: message.originalTimestamp,
-                            content: message.content,
-                            mentions: message.mentions,
-                            isPrivate: message.isPrivate,
-                            recipientPeerID: message.recipientPeerID,
-                            recipientNickname: message.recipientNickname,
-                            retryCount: message.retryCount + 1,
-                            nextRetryTime: Date().addingTimeInterval(self.retryInterval * Double(message.retryCount + 2))
-                        )
-                        self.retryQueue.append(updatedMessage)
-                    }
-                } else {
-                    // Regular message
-                    if !connectedPeers.isEmpty {
-                        meshService.sendMessage(
-                            message.content,
-                            mentions: message.mentions ?? [],
-                            to: nil,
-                            messageID: message.originalMessageID,
-                            timestamp: message.originalTimestamp
-                        )
-                    } else {
-                        // No peers connected, keep in queue
-                        var updatedMessage = message
-                        updatedMessage = RetryableMessage(
-                            id: message.id,
-                            originalMessageID: message.originalMessageID,
-                            originalTimestamp: message.originalTimestamp,
-                            content: message.content,
-                            mentions: message.mentions,
-                            isPrivate: message.isPrivate,
-                            recipientPeerID: message.recipientPeerID,
-                            recipientNickname: message.recipientNickname,
-                            retryCount: message.retryCount + 1,
-                            nextRetryTime: Date().addingTimeInterval(self.retryInterval * Double(message.retryCount + 2))
-                        )
-                        self.retryQueue.append(updatedMessage)
-                    }
-                }
-            }
-        }
-    }
-    
-    func clearRetryQueue() {
-        retryQueue.removeAll()
-    }
-    
-    func getRetryQueueCount() -> Int {
-        return retryQueue.count
-    }
-}

bitchat/Services/MessageRouter.swift

@@ -0,0 +1,133 @@
+import BitLogger
+import Foundation
+
+/// Routes messages between BLE and Nostr transports
+@MainActor
+final class MessageRouter {
+    private let mesh: Transport
+    private let nostr: NostrTransport
+    private var outbox: [PeerID: [(content: String, nickname: String, messageID: String)]] = [:] // peerID -> queued messages
+
+    init(mesh: Transport, nostr: NostrTransport) {
+        self.mesh = mesh
+        self.nostr = nostr
+        self.nostr.senderPeerID = mesh.myPeerID
+
+        // Observe favorites changes to learn Nostr mapping and flush queued messages
+        NotificationCenter.default.addObserver(
+            forName: .favoriteStatusChanged,
+            object: nil,
+            queue: .main
+        ) { [weak self] note in
+            guard let self = self else { return }
+            if let data = note.userInfo?["peerPublicKey"] as? Data {
+                let peerID = PeerID(publicKey: data)
+                Task { @MainActor in
+                    self.flushOutbox(for: peerID)
+                }
+            }
+            // Handle key updates
+            if let newKey = note.userInfo?["peerPublicKey"] as? Data,
+               let _ = note.userInfo?["isKeyUpdate"] as? Bool {
+                let peerID = PeerID(publicKey: newKey)
+                Task { @MainActor in
+                    self.flushOutbox(for: peerID)
+                }
+            }
+        }
+    }
+
+    func sendPrivate(_ content: String, to peerID: PeerID, recipientNickname: String, messageID: String) {
+        let reachableMesh = mesh.isPeerReachable(peerID)
+        if reachableMesh {
+            SecureLogger.debug("Routing PM via mesh (reachable) to \(peerID.id.prefix(8))… id=\(messageID.prefix(8))…", category: .session)
+            // BLEService will initiate a handshake if needed and queue the message
+            mesh.sendPrivateMessage(content, to: peerID, recipientNickname: recipientNickname, messageID: messageID)
+        } else if canSendViaNostr(peerID: peerID) {
+            SecureLogger.debug("Routing PM via Nostr to \(peerID.id.prefix(8))… id=\(messageID.prefix(8))…", category: .session)
+            nostr.sendPrivateMessage(content, to: peerID, recipientNickname: recipientNickname, messageID: messageID)
+        } else {
+            // Queue for later (when mesh connects or Nostr mapping appears)
+            if outbox[peerID] == nil { outbox[peerID] = [] }
+            outbox[peerID]?.append((content, recipientNickname, messageID))
+            SecureLogger.debug("Queued PM for \(peerID.id.prefix(8))… (no mesh, no Nostr mapping) id=\(messageID.prefix(8))…", category: .session)
+        }
+    }
+
+    func sendReadReceipt(_ receipt: ReadReceipt, to peerID: PeerID) {
+        // Prefer mesh for reachable peers; BLE will queue if handshake is needed
+        if mesh.isPeerReachable(peerID) {
+            SecureLogger.debug("Routing READ ack via mesh (reachable) to \(peerID.id.prefix(8))… id=\(receipt.originalMessageID.prefix(8))…", category: .session)
+            mesh.sendReadReceipt(receipt, to: peerID)
+        } else {
+            SecureLogger.debug("Routing READ ack via Nostr to \(peerID.id.prefix(8))… id=\(receipt.originalMessageID.prefix(8))…", category: .session)
+            nostr.sendReadReceipt(receipt, to: peerID)
+        }
+    }
+
+    func sendDeliveryAck(_ messageID: String, to peerID: PeerID) {
+        if mesh.isPeerReachable(peerID) {
+            SecureLogger.debug("Routing DELIVERED ack via mesh (reachable) to \(peerID.id.prefix(8))… id=\(messageID.prefix(8))…", category: .session)
+            mesh.sendDeliveryAck(for: messageID, to: peerID)
+        } else {
+            nostr.sendDeliveryAck(for: messageID, to: peerID)
+        }
+    }
+
+    func sendFavoriteNotification(to peerID: PeerID, isFavorite: Bool) {
+        // Route via mesh when connected; else use Nostr
+        if mesh.isPeerConnected(peerID) {
+            mesh.sendFavoriteNotification(to: peerID, isFavorite: isFavorite)
+        } else {
+            nostr.sendFavoriteNotification(to: peerID, isFavorite: isFavorite)
+        }
+    }
+
+    // MARK: - Outbox Management
+    private func canSendViaNostr(peerID: PeerID) -> Bool {
+        // Two forms are supported:
+        // - 64-hex Noise public key (32 bytes)
+        // - 16-hex short peer ID (derived from Noise pubkey)
+        if let noiseKey = peerID.noiseKey {
+            if let fav = FavoritesPersistenceService.shared.getFavoriteStatus(for: noiseKey),
+               fav.peerNostrPublicKey != nil {
+                return true
+            }
+        } else if peerID.isShort {
+            if let fav = FavoritesPersistenceService.shared.getFavoriteStatus(forPeerID: peerID),
+               fav.peerNostrPublicKey != nil {
+                return true
+            }
+        }
+        return false
+    }
+
+    func flushOutbox(for peerID: PeerID) {
+        guard let queued = outbox[peerID], !queued.isEmpty else { return }
+        SecureLogger.debug("Flushing outbox for \(peerID.id.prefix(8))… count=\(queued.count)", category: .session)
+        var remaining: [(content: String, nickname: String, messageID: String)] = []
+        // Prefer mesh if connected; else try Nostr if mapping exists
+        for (content, nickname, messageID) in queued {
+            if mesh.isPeerReachable(peerID) {
+                SecureLogger.debug("Outbox -> mesh for \(peerID.id.prefix(8))… id=\(messageID.prefix(8))…", category: .session)
+                mesh.sendPrivateMessage(content, to: peerID, recipientNickname: nickname, messageID: messageID)
+            } else if canSendViaNostr(peerID: peerID) {
+                SecureLogger.debug("Outbox -> Nostr for \(peerID.id.prefix(8))… id=\(messageID.prefix(8))…", category: .session)
+                nostr.sendPrivateMessage(content, to: peerID, recipientNickname: nickname, messageID: messageID)
+            } else {
+                // Keep unsent items queued
+                remaining.append((content, nickname, messageID))
+            }
+        }
+        // Persist only items we could not send
+        if remaining.isEmpty {
+            outbox.removeValue(forKey: peerID)
+        } else {
+            outbox[peerID] = remaining
+        }
+    }
+
+    func flushAllOutbox() {
+        for key in Array(outbox.keys) { flushOutbox(for: key) }
+    }
+}

bitchat/Services/NetworkActivationService.swift

@@ -0,0 +1,114 @@
+import Foundation
+import BitLogger
+import Combine
+import Tor
+
+/// Coordinates when the app is allowed to start Tor and connect to Nostr relays.
+/// Policy: permit start when either location permissions are authorized OR
+/// there exists at least one mutual favorite. Otherwise, do not start.
+@MainActor
+final class NetworkActivationService: ObservableObject {
+    static let shared = NetworkActivationService()
+
+    @Published private(set) var activationAllowed: Bool = false
+    @Published private(set) var userTorEnabled: Bool = true
+
+    private var cancellables = Set<AnyCancellable>()
+    private var started = false
+    private let torPreferenceKey = "networkActivationService.userTorEnabled"
+    private var torAutoStartDesired: Bool = false
+
+    private init() {}
+
+    func start() {
+        guard !started else { return }
+        started = true
+
+        if let stored = UserDefaults.standard.object(forKey: torPreferenceKey) as? Bool {
+            userTorEnabled = stored
+        } else {
+            userTorEnabled = true
+        }
+
+        // Initial compute
+        let allowed = basePolicyAllowed()
+        activationAllowed = allowed
+        torAutoStartDesired = allowed && userTorEnabled
+        TorManager.shared.setAutoStartAllowed(torAutoStartDesired)
+        applyTorState(torDesired: torAutoStartDesired)
+        if allowed {
+            NostrRelayManager.shared.connect()
+        } else {
+            NostrRelayManager.shared.disconnect()
+        }
+
+        // React to location permission changes
+        LocationChannelManager.shared.$permissionState
+            .receive(on: DispatchQueue.main)
+            .sink { [weak self] _ in
+                self?.reevaluate()
+            }
+            .store(in: &cancellables)
+
+        // React to mutual favorites changes
+        FavoritesPersistenceService.shared.$mutualFavorites
+            .receive(on: DispatchQueue.main)
+            .sink { [weak self] _ in
+                self?.reevaluate()
+            }
+            .store(in: &cancellables)
+    }
+
+    func setUserTorEnabled(_ enabled: Bool) {
+        guard enabled != userTorEnabled else { return }
+        userTorEnabled = enabled
+        UserDefaults.standard.set(enabled, forKey: torPreferenceKey)
+        NotificationCenter.default.post(
+            name: .TorUserPreferenceChanged,
+            object: nil,
+            userInfo: ["enabled": enabled]
+        )
+        reevaluate()
+    }
+
+    private func reevaluate() {
+        let allowed = basePolicyAllowed()
+        let torDesired = allowed && userTorEnabled
+        let statusChanged = allowed != activationAllowed
+        let torChanged = torDesired != torAutoStartDesired
+        if statusChanged {
+            SecureLogger.info("NetworkActivationService: activationAllowed -> \(allowed)", category: .session)
+            activationAllowed = allowed
+        }
+        if statusChanged || torChanged {
+            torAutoStartDesired = torDesired
+            TorManager.shared.setAutoStartAllowed(torDesired)
+            applyTorState(torDesired: torDesired)
+        }
+
+        if allowed {
+            if torChanged {
+                // Reset relay sockets when switching transport path (Tor ↔︎ direct)
+                NostrRelayManager.shared.disconnect()
+            }
+            NostrRelayManager.shared.connect()
+        } else if statusChanged {
+            NostrRelayManager.shared.disconnect()
+        }
+    }
+
+    private func basePolicyAllowed() -> Bool {
+        let permOK = LocationChannelManager.shared.permissionState == .authorized
+        let hasMutual = !FavoritesPersistenceService.shared.mutualFavorites.isEmpty
+        return permOK || hasMutual
+    }
+
+    private func applyTorState(torDesired: Bool) {
+        TorURLSession.shared.setProxyMode(useTor: torDesired)
+        if torDesired {
+            TorManager.shared.startIfNeeded()
+        } else {
+            TorManager.shared.shutdownCompletely()
+        }
+    }
+}

bitchat/Services/NoiseEncryptionService.swift

@@ -6,12 +6,90 @@
 // For more information, see <https://unlicense.org>
 //
 
+///
+/// # NoiseEncryptionService
+///
+/// High-level encryption service that manages Noise Protocol sessions for secure
+/// peer-to-peer communication in BitChat. Acts as the bridge between the transport
+/// layer (BLEService) and the cryptographic layer (NoiseProtocol).
+///
+/// ## Overview
+/// This service provides a simplified API for establishing and managing encrypted
+/// channels between peers. It handles:
+/// - Static identity key management
+/// - Session lifecycle (creation, maintenance, teardown)
+/// - Message encryption/decryption
+/// - Peer authentication and fingerprint tracking
+/// - Automatic rekeying for forward secrecy
+///
+/// ## Architecture
+/// The service operates at multiple levels:
+/// 1. **Identity Management**: Persistent Curve25519 keys stored in Keychain
+/// 2. **Session Management**: Per-peer Noise sessions with state tracking
+/// 3. **Message Processing**: Encryption/decryption with proper framing
+/// 4. **Security Features**: Rate limiting, fingerprint verification
+///
+/// ## Key Features
+///
+/// ### Identity Keys
+/// - Static Curve25519 key pair for Noise XX pattern
+/// - Ed25519 signing key pair for additional authentication
+/// - Keys persisted securely in iOS/macOS Keychain
+/// - Fingerprints derived from SHA256 of public keys
+///
+/// ### Session Management
+/// - Lazy session creation (on-demand when sending messages)
+/// - Automatic session recovery after disconnections
+/// - Configurable rekey intervals for forward secrecy
+/// - Graceful handling of simultaneous handshakes
+///
+/// ### Security Properties
+/// - Forward secrecy via ephemeral keys in handshakes
+/// - Mutual authentication via static key exchange
+/// - Protection against replay attacks
+/// - Rate limiting to prevent DoS attacks
+///
+/// ## Encryption Flow
+/// ```
+/// 1. Message arrives for encryption
+/// 2. Check if session exists for peer
+/// 3. If not, initiate Noise handshake
+/// 4. Once established, encrypt message
+/// 5. Add message type header for protocol handling
+/// 6. Return encrypted payload for transmission
+/// ```
+///
+/// ## Integration Points
+/// - **BLEService**: Calls this service for all private messages
+/// - **ChatViewModel**: Monitors encryption status for UI indicators
+/// - **KeychainManager**: Secure storage for identity keys
+///
+/// ## Thread Safety
+/// - Concurrent read access via reader-writer queue
+/// - Session operations protected by per-peer queues
+/// - Atomic updates for critical state changes
+///
+/// ## Error Handling
+/// - Graceful fallback for encryption failures
+/// - Clear error messages for debugging
+/// - Automatic retry with exponential backoff
+/// - User notification for critical failures
+///
+/// ## Performance Considerations
+/// - Sessions cached in memory for fast access
+/// - Minimal allocations in hot paths
+/// - Efficient binary message format
+/// - Background queue for CPU-intensive operations
+///
+
+import BitLogger
 import Foundation
 import CryptoKit
-import os.log
 
 // MARK: - Encryption Status
 
+/// Represents the current encryption status of a peer connection.
+/// Used for UI indicators and decision-making about message handling.
 enum EncryptionStatus: Equatable {
     case none                // Failed or incompatible
     case noHandshake        // No handshake attempted yet
@@ -30,29 +108,48 @@ enum EncryptionStatus: Equatable {
         case .noiseSecured:
             return "lock.fill"  // Changed from "lock" to "lock.fill" for filled lock
         case .noiseVerified:
-            return "lock.shield.fill"  // Changed to filled version for consistency
+            return "checkmark.seal.fill"  // Verified badge
         }
     }
     
     var description: String {
         switch self {
         case .none:
-            return "Encryption failed"
+            return String(localized: "encryption.status.failed", comment: "Status text when encryption failed")
         case .noHandshake:
-            return "Not encrypted"
+            return String(localized: "encryption.status.not_encrypted", comment: "Status text when no encryption handshake happened")
         case .noiseHandshaking:
-            return "Establishing encryption..."
+            return String(localized: "encryption.status.establishing", comment: "Status text when encryption is being established")
         case .noiseSecured:
-            return "Encrypted"
+            return String(localized: "encryption.status.secured", comment: "Status text when encryption is secured but not verified")
         case .noiseVerified:
-            return "Encrypted & Verified"
+            return String(localized: "encryption.status.verified", comment: "Status text when encryption is verified")
+        }
+    }
+
+    var accessibilityDescription: String {
+        switch self {
+        case .none:
+            return String(localized: "encryption.accessibility.failed", comment: "Accessibility text when encryption failed")
+        case .noHandshake:
+            return String(localized: "encryption.accessibility.not_encrypted", comment: "Accessibility text when encryption is not established")
+        case .noiseHandshaking:
+            return String(localized: "encryption.accessibility.establishing", comment: "Accessibility text when encryption is being established")
+        case .noiseSecured:
+            return String(localized: "encryption.accessibility.secured", comment: "Accessibility text when encryption is secured")
+        case .noiseVerified:
+            return String(localized: "encryption.accessibility.verified", comment: "Accessibility text when encryption is verified")
         }
     }
 }
 
 // MARK: - Noise Encryption Service
 
-class NoiseEncryptionService {
+/// Manages end-to-end encryption for BitChat using the Noise Protocol Framework.
+/// Provides a high-level API for establishing secure channels between peers,
+/// handling all cryptographic operations transparently.
+/// - Important: This service maintains the device's cryptographic identity
+final class NoiseEncryptionService {
     // Static identity key (persistent across sessions)
     private let staticIdentityKey: Curve25519.KeyAgreement.PrivateKey
     public let staticIdentityPublicKey: Curve25519.KeyAgreement.PublicKey
@@ -65,32 +162,52 @@ class NoiseEncryptionService {
     private let sessionManager: NoiseSessionManager
     
     // Peer fingerprints (SHA256 hash of static public key)
-    private var peerFingerprints: [String: String] = [:] // peerID -> fingerprint
-    private var fingerprintToPeerID: [String: String] = [:] // fingerprint -> peerID
+    private var peerFingerprints: [PeerID: String] = [:]
+    private var fingerprintToPeerID: [String: PeerID] = [:]
     
     // Thread safety
     private let serviceQueue = DispatchQueue(label: "chat.bitchat.noise.service", attributes: .concurrent)
     
     // Security components
     private let rateLimiter = NoiseRateLimiter()
+    private let keychain: KeychainManagerProtocol
     
     // Session maintenance
     private var rekeyTimer: Timer?
     private let rekeyCheckInterval: TimeInterval = 60.0 // Check every minute
     
     // Callbacks
-    var onPeerAuthenticated: ((String, String) -> Void)? // peerID, fingerprint
-    var onHandshakeRequired: ((String) -> Void)? // peerID needs handshake
+    private var onPeerAuthenticatedHandlers: [((PeerID, String) -> Void)] = [] // Array of handlers for peer authentication
+    var onHandshakeRequired: ((PeerID) -> Void)? // peerID needs handshake
     
-    init() {
+    // Add a handler for peer authentication
+    func addOnPeerAuthenticatedHandler(_ handler: @escaping (PeerID, String) -> Void) {
+        serviceQueue.async(flags: .barrier) { [weak self] in
+            self?.onPeerAuthenticatedHandlers.append(handler)
+        }
+    }
+    
+    // Legacy support - setting this will add to the handlers array
+    var onPeerAuthenticated: ((PeerID, String) -> Void)? {
+        get { nil } // Always return nil for backward compatibility
+        set {
+            if let handler = newValue {
+                addOnPeerAuthenticatedHandler(handler)
+            }
+        }
+    }
+    
+    init(keychain: KeychainManagerProtocol) {
+        self.keychain = keychain
+        
         // Load or create static identity key (ONLY from keychain)
         let loadedKey: Curve25519.KeyAgreement.PrivateKey
         
         // Try to load from keychain
-        if let identityData = KeychainManager.shared.getIdentityKey(forKey: "noiseStaticKey"),
+        if let identityData = keychain.getIdentityKey(forKey: "noiseStaticKey"),
            let key = try? Curve25519.KeyAgreement.PrivateKey(rawRepresentation: identityData) {
             loadedKey = key
-            SecureLogger.logKeyOperation("load", keyType: "noiseStaticKey", success: true)
+            SecureLogger.logKeyOperation(.load, keyType: "noiseStaticKey", success: true)
         }
         // If no identity exists, create new one
         else {
@@ -98,8 +215,8 @@ class NoiseEncryptionService {
             let keyData = loadedKey.rawRepresentation
             
             // Save to keychain
-            let saved = KeychainManager.shared.saveIdentityKey(keyData, forKey: "noiseStaticKey")
-            SecureLogger.logKeyOperation("create", keyType: "noiseStaticKey", success: saved)
+            let saved = keychain.saveIdentityKey(keyData, forKey: "noiseStaticKey")
+            SecureLogger.logKeyOperation(.create, keyType: "noiseStaticKey", success: saved)
         }
         
         // Now assign the final value
@@ -110,10 +227,10 @@ class NoiseEncryptionService {
         let loadedSigningKey: Curve25519.Signing.PrivateKey
         
         // Try to load from keychain
-        if let signingData = KeychainManager.shared.getIdentityKey(forKey: "ed25519SigningKey"),
+        if let signingData = keychain.getIdentityKey(forKey: "ed25519SigningKey"),
            let key = try? Curve25519.Signing.PrivateKey(rawRepresentation: signingData) {
             loadedSigningKey = key
-            SecureLogger.logKeyOperation("load", keyType: "ed25519SigningKey", success: true)
+            SecureLogger.logKeyOperation(.load, keyType: "ed25519SigningKey", success: true)
         }
         // If no signing key exists, create new one
         else {
@@ -121,8 +238,8 @@ class NoiseEncryptionService {
             let keyData = loadedSigningKey.rawRepresentation
             
             // Save to keychain
-            let saved = KeychainManager.shared.saveIdentityKey(keyData, forKey: "ed25519SigningKey")
-            SecureLogger.logKeyOperation("create", keyType: "ed25519SigningKey", success: saved)
+            let saved = keychain.saveIdentityKey(keyData, forKey: "ed25519SigningKey")
+            SecureLogger.logKeyOperation(.create, keyType: "ed25519SigningKey", success: saved)
         }
         
         // Now assign the signing keys
@@ -130,7 +247,7 @@ class NoiseEncryptionService {
         self.signingPublicKey = signingKey.publicKey
         
         // Initialize session manager
-        self.sessionManager = NoiseSessionManager(localStaticKey: staticIdentityKey)
+        self.sessionManager = NoiseSessionManager(localStaticKey: staticIdentityKey, keychain: keychain)
         
         // Set up session callbacks
         sessionManager.onSessionEstablished = { [weak self] peerID, remoteStaticKey in
@@ -155,22 +272,21 @@ class NoiseEncryptionService {
     
     /// Get our identity fingerprint
     func getIdentityFingerprint() -> String {
-        let hash = SHA256.hash(data: staticIdentityPublicKey.rawRepresentation)
-        return hash.map { String(format: "%02x", $0) }.joined()
+        staticIdentityPublicKey.rawRepresentation.sha256Fingerprint()
     }
     
     /// Get peer's public key data
-    func getPeerPublicKeyData(_ peerID: String) -> Data? {
+    func getPeerPublicKeyData(_ peerID: PeerID) -> Data? {
         return sessionManager.getRemoteStaticKey(for: peerID)?.rawRepresentation
     }
     
     /// Clear persistent identity (for panic mode)
     func clearPersistentIdentity() {
         // Clear from keychain
-        let deletedStatic = KeychainManager.shared.deleteIdentityKey(forKey: "noiseStaticKey")
-        let deletedSigning = KeychainManager.shared.deleteIdentityKey(forKey: "ed25519SigningKey")
-        SecureLogger.logKeyOperation("delete", keyType: "identity keys", success: deletedStatic && deletedSigning)
-        SecureLogger.log("Panic mode activated - identity cleared", category: SecureLogger.security, level: .warning)
+        let deletedStatic = keychain.deleteIdentityKey(forKey: "noiseStaticKey")
+        let deletedSigning = keychain.deleteIdentityKey(forKey: "ed25519SigningKey")
+        SecureLogger.logKeyOperation(.delete, keyType: "identity keys", success: deletedStatic && deletedSigning)
+        SecureLogger.warning("Panic mode activated - identity cleared", category: .security)
         // Stop rekey timer
         stopRekeyTimer()
     }
@@ -181,7 +297,7 @@ class NoiseEncryptionService {
             let signature = try signingKey.signature(for: data)
             return signature
         } catch {
-            SecureLogger.logError(error, context: "Failed to sign data", category: SecureLogger.noise)
+            SecureLogger.error(error, context: "Failed to sign data")
             return nil
         }
     }
@@ -192,29 +308,117 @@ class NoiseEncryptionService {
             let signingPublicKey = try Curve25519.Signing.PublicKey(rawRepresentation: publicKey)
             return signingPublicKey.isValidSignature(signature, for: data)
         } catch {
-            SecureLogger.logError(error, context: "Failed to verify signature", category: SecureLogger.noise)
+            SecureLogger.error(error, context: "Failed to verify signature")
             return false
         }
     }
+
+    // MARK: - Announce Signature Helpers
+
+    /// Build the canonical announce binding message bytes and sign with our Ed25519 key
+    /// - Parameters:
+    ///   - peerID: 8-byte routing ID (as in packet header)
+    ///   - noiseKey: 32-byte Curve25519.KeyAgreement public key
+    ///   - ed25519Key: 32-byte Ed25519 public key (self)
+    ///   - nickname: UTF-8 nickname (<=255 bytes)
+    ///   - timestampMs: UInt64 milliseconds since epoch
+    /// - Returns: Ed25519 signature over the canonical bytes, or nil on failure
+    func buildAnnounceSignature(peerID: Data, noiseKey: Data, ed25519Key: Data, nickname: String, timestampMs: UInt64) -> Data? {
+        let message = canonicalAnnounceBytes(peerID: peerID, noiseKey: noiseKey, ed25519Key: ed25519Key, nickname: nickname, timestampMs: timestampMs)
+        return signData(message)
+    }
+
+    /// Verify an announce signature
+    func verifyAnnounceSignature(signature: Data, peerID: Data, noiseKey: Data, ed25519Key: Data, nickname: String, timestampMs: UInt64, publicKey: Data) -> Bool {
+        let message = canonicalAnnounceBytes(peerID: peerID, noiseKey: noiseKey, ed25519Key: ed25519Key, nickname: nickname, timestampMs: timestampMs)
+        return verifySignature(signature, for: message, publicKey: publicKey)
+    }
+
+    /// Build canonical bytes for announce signing.
+    private func canonicalAnnounceBytes(peerID: Data, noiseKey: Data, ed25519Key: Data, nickname: String, timestampMs: UInt64) -> Data {
+        var out = Data()
+        // context
+        let context = "bitchat-announce-v1".data(using: .utf8) ?? Data()
+        out.append(UInt8(min(context.count, 255)))
+        out.append(context.prefix(255))
+        // peerID (expect 8 bytes; pad/truncate to 8 for canonicalization)
+        let peerID8 = peerID.prefix(8)
+        out.append(peerID8)
+        if peerID8.count < 8 { out.append(Data(repeating: 0, count: 8 - peerID8.count)) }
+        // noise static key (expect 32)
+        let noise32 = noiseKey.prefix(32)
+        out.append(noise32)
+        if noise32.count < 32 { out.append(Data(repeating: 0, count: 32 - noise32.count)) }
+        // ed25519 public key (expect 32)
+        let ed32 = ed25519Key.prefix(32)
+        out.append(ed32)
+        if ed32.count < 32 { out.append(Data(repeating: 0, count: 32 - ed32.count)) }
+        // nickname length + bytes
+        let nickData = nickname.data(using: .utf8) ?? Data()
+        out.append(UInt8(min(nickData.count, 255)))
+        out.append(nickData.prefix(255))
+        // timestamp
+        var ts = timestampMs.bigEndian
+        withUnsafeBytes(of: &ts) { raw in out.append(contentsOf: raw) }
+        return out
+    }
+    
+    // MARK: - Packet Signing/Verification
+    
+    /// Sign a BitchatPacket using the noise private key
+    func signPacket(_ packet: BitchatPacket) -> BitchatPacket? {
+        // Create canonical packet bytes for signing
+        guard let packetData = packet.toBinaryDataForSigning() else {
+            return nil
+        }
+        
+        // Sign with the noise private key (converted to Ed25519 for signing)
+        guard let signature = signData(packetData) else {
+            return nil
+        }
+        
+        // Return new packet with signature
+        var signedPacket = packet
+        signedPacket.signature = signature
+        return signedPacket
+    }
+    
+    /// Verify a BitchatPacket signature using the provided public key
+    func verifyPacketSignature(_ packet: BitchatPacket, publicKey: Data) -> Bool {
+        guard let signature = packet.signature else {
+            return false
+        }
+        
+        // Create canonical packet bytes for verification (without signature)
+        
+        guard let packetData = packet.toBinaryDataForSigning() else {
+            return false
+        }
+        
+        // For noise public keys, we need to derive the Ed25519 key for verification
+        // This assumes the noise key can be used for Ed25519 signing
+        return verifySignature(signature, for: packetData, publicKey: publicKey)
+    }
+
     
     // MARK: - Handshake Management
     
     /// Initiate a Noise handshake with a peer
-    func initiateHandshake(with peerID: String) throws -> Data {
+    func initiateHandshake(with peerID: PeerID) throws -> Data {
         
         // Validate peer ID
-        guard NoiseSecurityValidator.validatePeerID(peerID) else {
-            SecureLogger.logSecurityEvent(.authenticationFailed(peerID: peerID), level: .warning)
+        guard peerID.isValid else {
+            SecureLogger.warning(.authenticationFailed(peerID: peerID.id))
             throw NoiseSecurityError.invalidPeerID
         }
         
         // Check rate limit
         guard rateLimiter.allowHandshake(from: peerID) else {
-            SecureLogger.logSecurityEvent(.authenticationFailed(peerID: "Rate limited: \(peerID)"), level: .warning)
+            SecureLogger.warning(.authenticationFailed(peerID: "Rate limited: \(peerID)"))
             throw NoiseSecurityError.rateLimitExceeded
         }
         
-        SecureLogger.logSecurityEvent(.handshakeStarted(peerID: peerID))
+        SecureLogger.info(.handshakeStarted(peerID: peerID.id))
         
         // Return raw handshake data without wrapper
         // The Noise protocol handles its own message format
@@ -223,23 +427,23 @@ class NoiseEncryptionService {
     }
     
     /// Process an incoming handshake message
-    func processHandshakeMessage(from peerID: String, message: Data) throws -> Data? {
+    func processHandshakeMessage(from peerID: PeerID, message: Data) throws -> Data? {
         
         // Validate peer ID
-        guard NoiseSecurityValidator.validatePeerID(peerID) else {
-            SecureLogger.logSecurityEvent(.authenticationFailed(peerID: peerID), level: .warning)
+        guard peerID.isValid else {
+            SecureLogger.warning(.authenticationFailed(peerID: peerID.id))
             throw NoiseSecurityError.invalidPeerID
         }
         
         // Validate message size
         guard NoiseSecurityValidator.validateHandshakeMessageSize(message) else {
-            SecureLogger.logSecurityEvent(.handshakeFailed(peerID: peerID, error: "Message too large"), level: .warning)
+            SecureLogger.warning(.handshakeFailed(peerID: peerID.id, error: "Message too large"))
             throw NoiseSecurityError.messageTooLarge
         }
         
         // Check rate limit
         guard rateLimiter.allowHandshake(from: peerID) else {
-            SecureLogger.logSecurityEvent(.authenticationFailed(peerID: "Rate limited: \(peerID)"), level: .warning)
+            SecureLogger.warning(.authenticationFailed(peerID: "Rate limited: \(peerID)"))
             throw NoiseSecurityError.rateLimitExceeded
         }
         
@@ -253,19 +457,19 @@ class NoiseEncryptionService {
     }
     
     /// Check if we have an established session with a peer
-    func hasEstablishedSession(with peerID: String) -> Bool {
+    func hasEstablishedSession(with peerID: PeerID) -> Bool {
         return sessionManager.getSession(for: peerID)?.isEstablished() ?? false
     }
     
     /// Check if we have a session (established or handshaking) with a peer
-    func hasSession(with peerID: String) -> Bool {
+    func hasSession(with peerID: PeerID) -> Bool {
         return sessionManager.getSession(for: peerID) != nil
     }
     
     // MARK: - Encryption/Decryption
     
     /// Encrypt data for a specific peer
-    func encrypt(_ data: Data, for peerID: String) throws -> Data {
+    func encrypt(_ data: Data, for peerID: PeerID) throws -> Data {
         // Validate message size
         guard NoiseSecurityValidator.validateMessageSize(data) else {
             throw NoiseSecurityError.messageTooLarge
@@ -287,7 +491,7 @@ class NoiseEncryptionService {
     }
     
     /// Decrypt data from a specific peer
-    func decrypt(_ data: Data, from peerID: String) throws -> Data {
+    func decrypt(_ data: Data, from peerID: PeerID) throws -> Data {
         // Validate message size
         guard NoiseSecurityValidator.validateMessageSize(data) else {
             throw NoiseSecurityError.messageTooLarge
@@ -309,56 +513,26 @@ class NoiseEncryptionService {
     // MARK: - Peer Management
     
     /// Get fingerprint for a peer
-    func getPeerFingerprint(_ peerID: String) -> String? {
+    func getPeerFingerprint(_ peerID: PeerID) -> String? {
         return serviceQueue.sync {
             return peerFingerprints[peerID]
         }
     }
-    
-    /// Get peer ID for a fingerprint
-    func getPeerID(for fingerprint: String) -> String? {
-        return serviceQueue.sync {
-            return fingerprintToPeerID[fingerprint]
-        }
-    }
-    
-    /// Remove a peer session
-    func removePeer(_ peerID: String) {
-        sessionManager.removeSession(for: peerID)
-        
+
+    func clearEphemeralStateForPanic() {
+        sessionManager.removeAllSessions()
         serviceQueue.sync(flags: .barrier) {
-            if let fingerprint = peerFingerprints[peerID] {
-                fingerprintToPeerID.removeValue(forKey: fingerprint)
-            }
-            peerFingerprints.removeValue(forKey: peerID)
+            peerFingerprints.removeAll()
+            fingerprintToPeerID.removeAll()
         }
-        
-        SecureLogger.logSecurityEvent(.sessionExpired(peerID: peerID))
-    }
-    
-    /// Migrate session when peer ID changes
-    func migratePeerSession(from oldPeerID: String, to newPeerID: String, fingerprint: String) {
-        // First update the fingerprint mappings
-        serviceQueue.sync(flags: .barrier) {
-            // Remove old mapping
-            if let oldFingerprint = peerFingerprints[oldPeerID], oldFingerprint == fingerprint {
-                peerFingerprints.removeValue(forKey: oldPeerID)
-            }
-            
-            // Add new mapping
-            peerFingerprints[newPeerID] = fingerprint
-            fingerprintToPeerID[fingerprint] = newPeerID
-        }
-        
-        // Migrate the session in session manager
-        sessionManager.migrateSession(from: oldPeerID, to: newPeerID)
+        rateLimiter.resetAll()
     }
     
     // MARK: - Private Helpers
     
-    private func handleSessionEstablished(peerID: String, remoteStaticKey: Curve25519.KeyAgreement.PublicKey) {
+    private func handleSessionEstablished(peerID: PeerID, remoteStaticKey: Curve25519.KeyAgreement.PublicKey) {
         // Calculate fingerprint
-        let fingerprint = calculateFingerprint(for: remoteStaticKey)
+        let fingerprint = remoteStaticKey.rawRepresentation.sha256Fingerprint()
         
         // Store fingerprint mapping
         serviceQueue.sync(flags: .barrier) {
@@ -367,15 +541,14 @@ class NoiseEncryptionService {
         }
         
         // Log security event
-        SecureLogger.logSecurityEvent(.handshakeCompleted(peerID: peerID))
+        SecureLogger.info(.handshakeCompleted(peerID: peerID.id))
         
-        // Notify about authentication
-        onPeerAuthenticated?(peerID, fingerprint)
-    }
-    
-    private func calculateFingerprint(for publicKey: Curve25519.KeyAgreement.PublicKey) -> String {
-        let hash = SHA256.hash(data: publicKey.rawRepresentation)
-        return hash.map { String(format: "%02x", $0) }.joined()
+        // Notify all handlers about authentication
+        serviceQueue.async { [weak self] in
+            self?.onPeerAuthenticatedHandlers.forEach { handler in
+                handler(peerID, fingerprint)
+            }
+        }
     }
         
     // MARK: - Session Maintenance
@@ -399,12 +572,12 @@ class NoiseEncryptionService {
             // Attempt to rekey the session
             do {
                 try sessionManager.initiateRekey(for: peerID)
-                SecureLogger.log("Key rotation initiated for peer: \(peerID)", category: SecureLogger.security, level: .info)
+                SecureLogger.debug("Key rotation initiated for peer: \(peerID)", category: .security)
                 
                 // Signal that handshake is needed
                 onHandshakeRequired?(peerID)
             } catch {
-                SecureLogger.logError(error, context: "Failed to initiate rekey for peer: \(peerID)", category: SecureLogger.session)
+                SecureLogger.error(error, context: "Failed to initiate rekey for peer: \(peerID)", category: .session)
             }
         }
     }
@@ -416,6 +589,8 @@ class NoiseEncryptionService {
 
 // MARK: - Protocol Message Types for Noise
 
+/// Message types for the Noise encryption protocol layer.
+/// These types wrap the underlying BitChat protocol messages with encryption metadata.
 enum NoiseMessageType: UInt8 {
     case handshakeInitiation = 0x10
     case handshakeResponse = 0x11
@@ -426,6 +601,9 @@ enum NoiseMessageType: UInt8 {
 
 // MARK: - Noise Message Wrapper
 
+/// Container for encrypted messages in the Noise protocol.
+/// Provides versioning and type information for proper message handling.
+/// The actual message content is encrypted in the payload field.
 struct NoiseMessage: Codable {
     let type: UInt8
     let sessionID: String  // Random ID for this handshake session

bitchat/Services/NostrTransport.swift

@@ -0,0 +1,262 @@
+import BitLogger
+import Foundation
+import Combine
+
+// Minimal Nostr transport conforming to Transport for offline sending
+final class NostrTransport: Transport {
+    // Provide BLE short peer ID for BitChat embedding
+    var senderPeerID = PeerID(str: "")
+
+    // Throttle READ receipts to avoid relay rate limits
+    private struct QueuedRead {
+        let receipt: ReadReceipt
+        let peerID: PeerID
+    }
+    private var readQueue: [QueuedRead] = []
+    private var isSendingReadAcks = false
+    private let readAckInterval: TimeInterval = TransportConfig.nostrReadAckInterval
+    private let keychain: KeychainManagerProtocol
+    private let idBridge: NostrIdentityBridge
+
+    init(keychain: KeychainManagerProtocol, idBridge: NostrIdentityBridge) {
+        self.keychain = keychain
+        self.idBridge = idBridge
+    }
+
+    // MARK: - Transport Protocol Conformance
+
+    weak var delegate: BitchatDelegate?
+    weak var peerEventsDelegate: TransportPeerEventsDelegate?
+
+    var peerSnapshotPublisher: AnyPublisher<[TransportPeerSnapshot], Never> {
+        Just([]).eraseToAnyPublisher()
+    }
+    func currentPeerSnapshots() -> [TransportPeerSnapshot] { [] }
+
+    var myPeerID: PeerID { senderPeerID }
+    var myNickname: String { "" }
+    func setNickname(_ nickname: String) { /* not used for Nostr */ }
+
+    func startServices() { /* no-op */ }
+    func stopServices() { /* no-op */ }
+    func emergencyDisconnectAll() { /* no-op */ }
+
+    func isPeerConnected(_ peerID: PeerID) -> Bool { false }
+    func isPeerReachable(_ peerID: PeerID) -> Bool { false }
+    func peerNickname(peerID: PeerID) -> String? { nil }
+    func getPeerNicknames() -> [PeerID : String] { [:] }
+
+    func getFingerprint(for peerID: PeerID) -> String? { nil }
+    func getNoiseSessionState(for peerID: PeerID) -> LazyHandshakeState { .none }
+    func triggerHandshake(with peerID: PeerID) { /* no-op */ }
+    
+    // Nostr does not use Noise sessions here; return a cached placeholder to avoid reallocation
+    private static var cachedNoiseService: NoiseEncryptionService?
+    func getNoiseService() -> NoiseEncryptionService {
+        if let noiseService = Self.cachedNoiseService {
+            return noiseService
+        }
+        let noiseService = NoiseEncryptionService(keychain: keychain)
+        Self.cachedNoiseService = noiseService
+        return noiseService
+    }
+
+    // Public broadcast not supported over Nostr here
+    func sendMessage(_ content: String, mentions: [String]) { /* no-op */ }
+
+    func sendPrivateMessage(_ content: String, to peerID: PeerID, recipientNickname: String, messageID: String) {
+        Task { @MainActor in
+            guard let recipientNpub = resolveRecipientNpub(for: peerID) else { return }
+            guard let senderIdentity = try? idBridge.getCurrentNostrIdentity() else { return }
+            SecureLogger.debug("NostrTransport: preparing PM to \(recipientNpub.prefix(16))… for peerID \(peerID.id.prefix(8))… id=\(messageID.prefix(8))…", category: .session)
+            // Convert recipient npub -> hex (x-only)
+            let recipientHex: String
+            do {
+                let (hrp, data) = try Bech32.decode(recipientNpub)
+                guard hrp == "npub" else {
+                    SecureLogger.error("NostrTransport: recipient key not npub (hrp=\(hrp))", category: .session)
+                    return
+                }
+                recipientHex = data.hexEncodedString()
+            } catch {
+                SecureLogger.error("NostrTransport: failed to decode npub -> hex: \(error)", category: .session)
+                return
+            }
+            guard let embedded = NostrEmbeddedBitChat.encodePMForNostr(content: content, messageID: messageID, recipientPeerID: peerID, senderPeerID: senderPeerID) else {
+                SecureLogger.error("NostrTransport: failed to embed PM packet", category: .session)
+                return
+            }
+            guard let event = try? NostrProtocol.createPrivateMessage(content: embedded, recipientPubkey: recipientHex, senderIdentity: senderIdentity) else {
+                SecureLogger.error("NostrTransport: failed to build Nostr event for PM", category: .session)
+                return
+            }
+            SecureLogger.debug("NostrTransport: sending PM giftWrap id=\(event.id.prefix(16))…", category: .session)
+            NostrRelayManager.shared.sendEvent(event)
+        }
+    }
+
+    func sendReadReceipt(_ receipt: ReadReceipt, to peerID: PeerID) {
+        // Enqueue and process with throttling to avoid relay rate limits
+        readQueue.append(QueuedRead(receipt: receipt, peerID: peerID))
+        processReadQueueIfNeeded()
+    }
+
+    func sendFavoriteNotification(to peerID: PeerID, isFavorite: Bool) {
+        Task { @MainActor in
+            guard let recipientNpub = resolveRecipientNpub(for: peerID) else { return }
+            guard let senderIdentity = try? idBridge.getCurrentNostrIdentity() else { return }
+            let content = isFavorite ? "[FAVORITED]:\(senderIdentity.npub)" : "[UNFAVORITED]:\(senderIdentity.npub)"
+            SecureLogger.debug("NostrTransport: preparing FAVORITE(\(isFavorite)) to \(recipientNpub.prefix(16))…", category: .session)
+            // Convert recipient npub -> hex
+            let recipientHex: String
+            do {
+                let (hrp, data) = try Bech32.decode(recipientNpub)
+                guard hrp == "npub" else { return }
+                recipientHex = data.hexEncodedString()
+            } catch { return }
+            guard let embedded = NostrEmbeddedBitChat.encodePMForNostr(content: content, messageID: UUID().uuidString, recipientPeerID: peerID, senderPeerID: senderPeerID) else {
+                SecureLogger.error("NostrTransport: failed to embed favorite notification", category: .session)
+                return
+            }
+            guard let event = try? NostrProtocol.createPrivateMessage(content: embedded, recipientPubkey: recipientHex, senderIdentity: senderIdentity) else {
+                SecureLogger.error("NostrTransport: failed to build Nostr event for favorite notification", category: .session)
+                return
+            }
+            SecureLogger.debug("NostrTransport: sending favorite giftWrap id=\(event.id.prefix(16))…", category: .session)
+            NostrRelayManager.shared.sendEvent(event)
+        }
+    }
+
+    func sendBroadcastAnnounce() { /* no-op for Nostr */ }
+    func sendDeliveryAck(for messageID: String, to peerID: PeerID) {
+        Task { @MainActor in
+            guard let recipientNpub = resolveRecipientNpub(for: peerID) else { return }
+            guard let senderIdentity = try? idBridge.getCurrentNostrIdentity() else { return }
+            SecureLogger.debug("NostrTransport: preparing DELIVERED ack for id=\(messageID.prefix(8))… to \(recipientNpub.prefix(16))…", category: .session)
+            let recipientHex: String
+            do {
+                let (hrp, data) = try Bech32.decode(recipientNpub)
+                guard hrp == "npub" else { return }
+                recipientHex = data.hexEncodedString()
+            } catch { return }
+            guard let ack = NostrEmbeddedBitChat.encodeAckForNostr(type: .delivered, messageID: messageID, recipientPeerID: peerID, senderPeerID: senderPeerID) else {
+                SecureLogger.error("NostrTransport: failed to embed DELIVERED ack", category: .session)
+                return
+            }
+            guard let event = try? NostrProtocol.createPrivateMessage(content: ack, recipientPubkey: recipientHex, senderIdentity: senderIdentity) else {
+                SecureLogger.error("NostrTransport: failed to build Nostr event for DELIVERED ack", category: .session)
+                return
+            }
+            SecureLogger.debug("NostrTransport: sending DELIVERED ack giftWrap id=\(event.id.prefix(16))…", category: .session)
+            NostrRelayManager.shared.sendEvent(event)
+        }
+    }
+}
+
+// MARK: - Geohash Helpers
+
+extension NostrTransport {
+
+    // MARK: Geohash ACK helpers
+    func sendDeliveryAckGeohash(for messageID: String, toRecipientHex recipientHex: String, from identity: NostrIdentity) {
+        Task { @MainActor in
+            SecureLogger.debug("GeoDM: send DELIVERED -> recip=\(recipientHex.prefix(8))… mid=\(messageID.prefix(8))… from=\(identity.publicKeyHex.prefix(8))…", category: .session)
+            guard let embedded = NostrEmbeddedBitChat.encodeAckForNostrNoRecipient(type: .delivered, messageID: messageID, senderPeerID: senderPeerID) else { return }
+            guard let event = try? NostrProtocol.createPrivateMessage(content: embedded, recipientPubkey: recipientHex, senderIdentity: identity) else { return }
+            NostrRelayManager.registerPendingGiftWrap(id: event.id)
+            NostrRelayManager.shared.sendEvent(event)
+        }
+    }
+
+    func sendReadReceiptGeohash(_ messageID: String, toRecipientHex recipientHex: String, from identity: NostrIdentity) {
+        Task { @MainActor in
+            SecureLogger.debug("GeoDM: send READ -> recip=\(recipientHex.prefix(8))… mid=\(messageID.prefix(8))… from=\(identity.publicKeyHex.prefix(8))…", category: .session)
+            guard let embedded = NostrEmbeddedBitChat.encodeAckForNostrNoRecipient(type: .readReceipt, messageID: messageID, senderPeerID: senderPeerID) else { return }
+            guard let event = try? NostrProtocol.createPrivateMessage(content: embedded, recipientPubkey: recipientHex, senderIdentity: identity) else { return }
+            NostrRelayManager.registerPendingGiftWrap(id: event.id)
+            NostrRelayManager.shared.sendEvent(event)
+        }
+    }
+
+    // MARK: Geohash DMs (per-geohash identity)
+    func sendPrivateMessageGeohash(content: String, toRecipientHex recipientHex: String, from identity: NostrIdentity, messageID: String) {
+        Task { @MainActor in
+            guard !recipientHex.isEmpty else { return }
+            SecureLogger.debug("GeoDM: send PM -> recip=\(recipientHex.prefix(8))… mid=\(messageID.prefix(8))… from=\(identity.publicKeyHex.prefix(8))…", category: .session)
+            // Build embedded BitChat packet without recipient peer ID
+            guard let embedded = NostrEmbeddedBitChat.encodePMForNostrNoRecipient(content: content, messageID: messageID, senderPeerID: senderPeerID) else {
+                SecureLogger.error("NostrTransport: failed to embed geohash PM packet", category: .session)
+                return
+            }
+            guard let event = try? NostrProtocol.createPrivateMessage(content: embedded, recipientPubkey: recipientHex, senderIdentity: identity) else {
+                SecureLogger.error("NostrTransport: failed to build Nostr event for geohash PM", category: .session)
+                return
+            }
+            SecureLogger.debug("NostrTransport: sending geohash PM giftWrap id=\(event.id.prefix(16))…", category: .session)
+            NostrRelayManager.registerPendingGiftWrap(id: event.id)
+            NostrRelayManager.shared.sendEvent(event)
+        }
+    }
+}
+
+// MARK: - Private Helpers
+
+extension NostrTransport {
+    private func processReadQueueIfNeeded() {
+        guard !isSendingReadAcks else { return }
+        guard !readQueue.isEmpty else { return }
+        isSendingReadAcks = true
+        sendNextReadAck()
+    }
+
+    private func sendNextReadAck() {
+        guard !readQueue.isEmpty else { isSendingReadAcks = false; return }
+        let item = readQueue.removeFirst()
+        Task { @MainActor in
+            guard let recipientNpub = resolveRecipientNpub(for: item.peerID) else { scheduleNextReadAck(); return }
+            guard let senderIdentity = try? idBridge.getCurrentNostrIdentity() else { scheduleNextReadAck(); return }
+            SecureLogger.debug("NostrTransport: preparing READ ack for id=\(item.receipt.originalMessageID.prefix(8))… to \(recipientNpub.prefix(16))…", category: .session)
+            // Convert recipient npub -> hex
+            let recipientHex: String
+            do {
+                let (hrp, data) = try Bech32.decode(recipientNpub)
+                guard hrp == "npub" else { scheduleNextReadAck(); return }
+                recipientHex = data.hexEncodedString()
+            } catch { scheduleNextReadAck(); return }
+            guard let ack = NostrEmbeddedBitChat.encodeAckForNostr(type: .readReceipt, messageID: item.receipt.originalMessageID, recipientPeerID: item.peerID, senderPeerID: senderPeerID) else {
+                SecureLogger.error("NostrTransport: failed to embed READ ack", category: .session)
+                scheduleNextReadAck(); return
+            }
+            guard let event = try? NostrProtocol.createPrivateMessage(content: ack, recipientPubkey: recipientHex, senderIdentity: senderIdentity) else {
+                SecureLogger.error("NostrTransport: failed to build Nostr event for READ ack", category: .session)
+                scheduleNextReadAck(); return
+            }
+            SecureLogger.debug("NostrTransport: sending READ ack giftWrap id=\(event.id.prefix(16))…", category: .session)
+            NostrRelayManager.shared.sendEvent(event)
+            scheduleNextReadAck()
+        }
+    }
+
+    private func scheduleNextReadAck() {
+        DispatchQueue.main.asyncAfter(deadline: .now() + readAckInterval) { [weak self] in
+            guard let self = self else { return }
+            self.isSendingReadAcks = false
+            self.processReadQueueIfNeeded()
+        }
+    }
+
+    @MainActor
+    private func resolveRecipientNpub(for peerID: PeerID) -> String? {
+        if let noiseKey = Data(hexString: peerID.id),
+           let fav = FavoritesPersistenceService.shared.getFavoriteStatus(for: noiseKey),
+           let npub = fav.peerNostrPublicKey {
+            return npub
+        }
+        if peerID.id.count == 16,
+           let fav = FavoritesPersistenceService.shared.getFavoriteStatus(forPeerID: peerID),
+           let npub = fav.peerNostrPublicKey {
+            return npub
+        }
+        return nil
+    }
+}

bitchat/Services/NotificationService.swift

@@ -14,7 +14,7 @@ import UIKit
 import AppKit
 #endif
 
-class NotificationService {
+final class NotificationService {
     static let shared = NotificationService()
     
     private init() {}
@@ -29,90 +29,68 @@ class NotificationService {
         }
     }
     
-    func sendLocalNotification(title: String, body: String, identifier: String, userInfo: [String: Any]? = nil) {
-        // For now, skip app state check entirely to avoid thread issues
-        // The NotificationDelegate will handle foreground presentation
-        DispatchQueue.main.async {
-            let content = UNMutableNotificationContent()
-            content.title = title
-            content.body = body
-            content.sound = .default
-            if let userInfo = userInfo {
-                content.userInfo = userInfo
-            }
-            
-            let request = UNNotificationRequest(
-                identifier: identifier,
-                content: content,
-                trigger: nil // Deliver immediately
-            )
-            
-            UNUserNotificationCenter.current().add(request) { _ in
-                // Notification added
-            }
+    func sendLocalNotification(
+        title: String,
+        body: String,
+        identifier: String,
+        userInfo: [String: Any]? = nil,
+        interruptionLevel: UNNotificationInterruptionLevel = .active
+    ) {
+        let content = UNMutableNotificationContent()
+        content.title = title
+        content.body = body
+        content.sound = .default
+        content.interruptionLevel = interruptionLevel
+
+        if let userInfo = userInfo {
+            content.userInfo = userInfo
         }
+
+        let request = UNNotificationRequest(
+            identifier: identifier,
+            content: content,
+            trigger: nil // Deliver immediately
+        )
+
+        UNUserNotificationCenter.current().add(request)
     }
     
     func sendMentionNotification(from sender: String, message: String) {
-        let title = "＠🫵 you were mentioned by \(sender)"
+        let title = "🫵 you were mentioned by \(sender)"
         let body = message
         let identifier = "mention-\(UUID().uuidString)"
         
         sendLocalNotification(title: title, body: body, identifier: identifier)
     }
     
-    func sendPrivateMessageNotification(from sender: String, message: String, peerID: String) {
-        let title = "🔒 private message from \(sender)"
+    func sendPrivateMessageNotification(from sender: String, message: String, peerID: PeerID) {
+        let title = "🔒 DM from \(sender)"
         let body = message
         let identifier = "private-\(UUID().uuidString)"
-        let userInfo = ["peerID": peerID, "senderName": sender]
+        let userInfo = ["peerID": peerID.id, "senderName": sender]
         
         sendLocalNotification(title: title, body: body, identifier: identifier, userInfo: userInfo)
     }
     
-    func sendFavoriteOnlineNotification(nickname: String) {
-        // Send directly without checking app state for favorites
-        DispatchQueue.main.async {
-            let content = UNMutableNotificationContent()
-            content.title = "⭐ \(nickname) is online!"
-            content.body = "wanna get in there?"
-            content.sound = .default
-            
-            let request = UNNotificationRequest(
-                identifier: "favorite-online-\(UUID().uuidString)",
-                content: content,
-                trigger: nil
-            )
-            
-            UNUserNotificationCenter.current().add(request) { _ in
-                // Notification added
-            }
-        }
+    // Geohash public chat notification with deep link to a specific geohash
+    func sendGeohashActivityNotification(geohash: String, titlePrefix: String = "#", bodyPreview: String) {
+        let title = "\(titlePrefix)\(geohash)"
+        let identifier = "geo-activity-\(geohash)-\(Date().timeIntervalSince1970)"
+        let deeplink = "bitchat://geohash/\(geohash)"
+        let userInfo: [String: Any] = ["deeplink": deeplink]
+        sendLocalNotification(title: title, body: bodyPreview, identifier: identifier, userInfo: userInfo)
     }
-    
+
     func sendNetworkAvailableNotification(peerCount: Int) {
         let title = "👥 bitchatters nearby!"
         let body = peerCount == 1 ? "1 person around" : "\(peerCount) people around"
         let identifier = "network-available-\(Date().timeIntervalSince1970)"
-        
-        // For network notifications, we want to show them even in foreground
-        // No app state check - let the notification delegate handle presentation
-        DispatchQueue.main.async {
-            let content = UNMutableNotificationContent()
-            content.title = title
-            content.body = body
-            content.sound = .default
-            content.interruptionLevel = .timeSensitive  // Make it more prominent
-            
-            let request = UNNotificationRequest(
-                identifier: identifier,
-                content: content,
-                trigger: nil // Deliver immediately
-            )
-            
-            UNUserNotificationCenter.current().add(request) { _ in
-                // Notification added
-            }
-        }
+
+        sendLocalNotification(
+            title: title,
+            body: body,
+            identifier: identifier,
+            interruptionLevel: .timeSensitive
+        )
     }
 }

bitchat/Services/NotificationStreamAssembler.swift

@@ -0,0 +1,133 @@
+//
+// NotificationStreamAssembler.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import BitLogger
+import Foundation
+
+struct NotificationStreamAssembler {
+    private var buffer = Data()
+    private var pendingFrameStartedAt: DispatchTime?
+    private var pendingFrameExpectedLength: Int = 0
+
+    private mutating func resetState() {
+        buffer.removeAll(keepingCapacity: false)
+        pendingFrameStartedAt = nil
+        pendingFrameExpectedLength = 0
+    }
+
+    mutating func append(_ chunk: Data) -> (frames: [Data], droppedPrefixes: [UInt8], reset: Bool) {
+        guard !chunk.isEmpty else { return ([], [], false) }
+
+        buffer.append(chunk)
+
+        var frames: [Data] = []
+        var dropped: [UInt8] = []
+        var didReset = false
+        let now = DispatchTime.now()
+        let maxFrameLength = TransportConfig.bleNotificationAssemblerHardCapBytes
+        let minimumFramePrefix = BinaryProtocol.v1HeaderSize + BinaryProtocol.senderIDSize
+
+        if buffer.count > TransportConfig.bleNotificationAssemblerHardCapBytes {
+            SecureLogger.error("❌ Notification assembler overflow (\(buffer.count) bytes); dropping partial frame", category: .session)
+            resetState()
+            return ([], [], true)
+        }
+
+        while buffer.count >= minimumFramePrefix {
+            guard let version = buffer.first else { break }
+            guard version == 1 || version == 2 else {
+                dropped.append(buffer.removeFirst())
+                pendingFrameStartedAt = nil
+                pendingFrameExpectedLength = 0
+                continue
+            }
+
+            guard let headerSize = BinaryProtocol.headerSize(for: version) else {
+                dropped.append(buffer.removeFirst())
+                pendingFrameStartedAt = nil
+                pendingFrameExpectedLength = 0
+                continue
+            }
+            let framePrefix = headerSize + BinaryProtocol.senderIDSize
+            guard buffer.count >= framePrefix else { break }
+
+            let flagsIndex = buffer.startIndex + BinaryProtocol.Offsets.flags
+            guard flagsIndex < buffer.endIndex else { break }
+            let flags = buffer[flagsIndex]
+            let hasRecipient = (flags & BinaryProtocol.Flags.hasRecipient) != 0
+            let hasSignature = (flags & BinaryProtocol.Flags.hasSignature) != 0
+            let isCompressed = (flags & BinaryProtocol.Flags.isCompressed) != 0
+
+            let lengthOffset = 12
+            let payloadLength: Int
+            if version == 2 {
+                let lengthIndex = buffer.startIndex + lengthOffset
+                payloadLength =
+                    (Int(buffer[lengthIndex]) << 24) |
+                    (Int(buffer[lengthIndex + 1]) << 16) |
+                    (Int(buffer[lengthIndex + 2]) << 8) |
+                    Int(buffer[lengthIndex + 3])
+            } else {
+                let lengthIndex = buffer.startIndex + lengthOffset
+                payloadLength = (Int(buffer[lengthIndex]) << 8) | Int(buffer[lengthIndex + 1])
+            }
+
+            var frameLength = framePrefix + payloadLength
+            if hasRecipient { frameLength += BinaryProtocol.recipientIDSize }
+            if hasSignature { frameLength += BinaryProtocol.signatureSize }
+            if isCompressed {
+                let rawLengthFieldBytes = (version == 2) ? 4 : 2
+                if payloadLength < rawLengthFieldBytes {
+                    SecureLogger.error("❌ Invalid compressed payload length (\(payloadLength))", category: .session)
+                    resetState()
+                    didReset = true
+                    break
+                }
+            }
+
+            guard frameLength > 0, frameLength <= maxFrameLength else {
+                SecureLogger.error("❌ Notification frame length \(frameLength) invalid (cap=\(maxFrameLength)); resetting stream", category: .session)
+                resetState()
+                didReset = true
+                break
+            }
+
+            if buffer.count < frameLength {
+                let remaining = frameLength - buffer.count
+                if pendingFrameStartedAt == nil || frameLength != pendingFrameExpectedLength {
+                    pendingFrameStartedAt = now
+                    pendingFrameExpectedLength = frameLength
+                } else if let started = pendingFrameStartedAt {
+                    let elapsed = now.uptimeNanoseconds - started.uptimeNanoseconds
+                    let threshold = UInt64(TransportConfig.bleAssemblerStallResetMs) * 1_000_000
+                    if elapsed >= threshold {
+                        SecureLogger.debug("📉 Resetting notification assembler after waiting \(remaining)B for \(TransportConfig.bleAssemblerStallResetMs)ms", category: .session)
+                        resetState()
+                        didReset = true
+                    } else {
+                        SecureLogger.debug("⌛ Waiting for remaining \(remaining)B to complete BLE frame", category: .session)
+                    }
+                }
+                break
+            }
+
+            pendingFrameStartedAt = nil
+            pendingFrameExpectedLength = 0
+
+            let frame = Data(buffer.prefix(frameLength))
+            frames.append(frame)
+            buffer.removeFirst(frameLength)
+        }
+
+        if !buffer.isEmpty, buffer.allSatisfy({ $0 == 0 }) {
+            resetState()
+        }
+
+        return (frames, dropped, didReset)
+    }
+}