Improve background BLE stability and nearby alerts (#864)

* Harden background BLE restoration and notifications

* Guard BLE restoration paths to iOS

---------

Co-authored-by: jack <jackjackbits@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

@@ -7,6 +7,7 @@ on:
 
 permissions:
   contents: write
+  pull-requests: write
 
 jobs:
   update-relay-data:
@@ -17,24 +18,54 @@ jobs:
         uses: actions/checkout@v4
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
-      
+          fetch-depth: 0
+
       - name: Fetch GeoRelays
         run: |
-          wget https://raw.githubusercontent.com/permissionlesstech/georelays/refs/heads/main/nostr_relays.csv
+          wget -q https://raw.githubusercontent.com/permissionlesstech/georelays/refs/heads/main/nostr_relays.csv
           mv nostr_relays.csv ./relays/online_relays_gps.csv
 
-      - name: Check for changes
-        id: git-check
+      - name: Configure git
         run: |
-          git diff --exit-code || echo "changes=true" >> $GITHUB_OUTPUT
-    
-      - name: Commit and push changes
-        if: steps.git-check.outputs.changes == 'true'
+          git config user.email "action@github.com"
+          git config user.name "GitHub Action"
+
+      - name: Create update branch if changes
+        id: create_branch
         run: |
-          git config --local user.email "action@github.com"
-          git config --local user.name "GitHub Action"
+          # 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)"
-          git push
-        env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          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

@@ -9,9 +9,6 @@ plans/
 CLAUDE.md
 AGENTS.md
 
-## User settings
-xcuserdata/
-
 ## compatibility with Xcode 8 and earlier (ignoring not required starting Xcode 9)
 *.xcscmblueprint
 *.xccheckout
@@ -57,7 +54,8 @@ iOSInjectionProject/
 
 ## Xcode project
 *.xcodeproj/project.xcworkspace/
-*.xcodeproj/xcshareddata/
+## Xcode User settings
+xcuserdata/
 
 ## Python
 __pycache__/
@@ -68,6 +66,9 @@ __pycache__/
 *.tmp
 *.temp
 
+## Cache
+.cache/
+
 # Local build results
 .Result*/
 .Result*.xcresult/
@@ -75,3 +76,6 @@ TestResult.xcresult/
 *.xcresult/
 build.log
 *.log
+
+# Local configs
+Local.xcconfig

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

Frameworks/README.md

@@ -1,12 +0,0 @@
-Place Tor.xcframework here
-
-Instructions
-- Obtain a prebuilt Tor Apple xcframework (iCepa/Onion Browser lineage) or build your own minimal client-only Tor.
-- Rename it (if needed) to `Tor.xcframework` and drop it in this `Frameworks/` directory.
-- Regenerate the Xcode project if you use XcodeGen (`project.yml` already references `Frameworks/Tor.xcframework`).
-- Build the app; `TorManager` will automatically bootstrap Tor and route all networking through it.
-
-Notes
-- For iOS, the framework will be embedded and code-signed automatically.
-- For macOS, it will be linked and embedded as well (you may prefer a system tor for smaller bundles).
-

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
 
@@ -44,15 +44,10 @@ 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
@@ -75,9 +70,7 @@ 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
+    @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
@@ -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.swift

@@ -4,6 +4,7 @@ import PackageDescription
 
 let package = Package(
     name: "bitchat",
+    defaultLocalization: "en",
     platforms: [
         .iOS(.v16),
         .macOS(.v13)
@@ -15,13 +16,17 @@ let package = Package(
         ),
     ],
     dependencies:[
-        .package(url: "https://github.com/21-DOT-DEV/swift-secp256k1", exact: "0.21.1"),
+        .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: "P256K", package: "swift-secp256k1"),
+                .product(name: "BitLogger", package: "BitLogger"),
+                .product(name: "Tor", package: "Tor")
             ],
             path: "bitchat",
             exclude: [
@@ -30,7 +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

@@ -9,7 +9,7 @@ A decentralized peer-to-peer messaging app with dual transport architecture: loc
 📲 [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](http://www.noiseprotocol.org) for identity and encryption. Public local chat (the main feature) has no security concerns.
+> 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
 
@@ -22,7 +22,7 @@ This project is released into the public domain. See the [LICENSE](LICENSE) file
 - **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
-- **Private Message End-to-End Encryption**: [Noise Protocol](http://noiseprotocol.org) for mesh, NIP-17 for Nostr
+- **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
@@ -94,45 +94,32 @@ For detailed protocol documentation, see the [Technical Whitepaper](WHITEPAPER.m
 
 ## Setup
 
-### Option 1: Using XcodeGen (Recommended)
-
-1. Install XcodeGen if you haven't already:
-
-   ```bash
-   brew install xcodegen
-   ```
-
-2. Generate the Xcode project:
+### Option 1: Using Xcode
 
    ```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`)
 
-1. Open the project in Xcode:
+### Option 2: Using `just`
 
    ```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.
 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

@@ -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

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/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

@@ -6,12 +6,16 @@
 // 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
@@ -22,7 +26,19 @@ struct BitchatApp: App {
     @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()
@@ -38,7 +54,7 @@ struct BitchatApp: App {
                     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? NostrIdentityBridge.getCurrentNostrIdentity()?.npub
+                        let npub = try? idBridge.getCurrentNostrIdentity()?.npub
                         _ = VerificationService.shared.buildMyQRString(nickname: chatViewModel.nickname, npub: npub)
                     }
                     #if os(iOS)
@@ -46,8 +62,8 @@ struct BitchatApp: App {
                     #elseif os(macOS)
                     appDelegate.chatViewModel = chatViewModel
                     #endif
-                    // Spin up Tor early; all internet will gate on Tor 100%
-                    TorManager.shared.startIfNeeded()
+                    // Initialize network activation policy; will start Tor/Nostr only when allowed
+                    NetworkActivationService.shared.start()
                     // Check for shared content
                     checkForSharedContent()
                 }
@@ -59,7 +75,7 @@ struct BitchatApp: App {
                     switch newPhase {
                     case .background:
                         // Keep BLE mesh running in background; BLEService adapts scanning automatically
-                        // Optionally nudge Tor to dormant to save power
+                        // Always send Tor to dormant on background for a clean restart later.
                         TorManager.shared.setAppForeground(false)
                         TorManager.shared.goDormantOnBackground()
                         // Stop geohash sampling while backgrounded
@@ -76,18 +92,22 @@ struct BitchatApp: App {
                         // On initial cold launch, Tor was just started in onAppear.
                         // Skip the deterministic restart the first time we become active.
                         if didHandleInitialActive && didEnterBackground {
-                            TorManager.shared.ensureRunningOnForeground()
+                            if TorManager.shared.isAutoStartAllowed() && !TorManager.shared.isReady {
+                                TorManager.shared.ensureRunningOnForeground()
+                            }
                         } else {
                             didHandleInitialActive = true
                         }
                         didEnterBackground = false
-                        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()
+                        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()
@@ -122,7 +142,7 @@ 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
         }
         
@@ -201,7 +221,7 @@ final 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))
                 }
             }
         }
@@ -226,7 +246,7 @@ final 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
                 }

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

@@ -87,7 +87,7 @@ import Foundation
 /// 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
 }
@@ -158,23 +158,6 @@ struct IdentityCache: Codable {
     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: - Migration Support

bitchat/Identity/SecureIdentityStateManager.swift

@@ -90,27 +90,63 @@
 /// - Advanced conflict resolution
 ///
 
+import BitLogger
 import Foundation
 import CryptoKit
 
+protocol SecureIdentityStateManagerProtocol {
+    // MARK: Secure Loading/Saving
+    func forceSave()
+    
+    // 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 {
-    static let shared = SecureIdentityStateManager()
-    
-    private let keychain = KeychainManager.shared
+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)
     
@@ -122,7 +158,9 @@ final 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
         
@@ -146,9 +184,13 @@ final 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
@@ -164,12 +206,7 @@ final class SecureIdentityStateManager {
         }
     }
     
-    deinit {
-        // Force save any pending changes
-        forceSave()
-    }
-    
-    func saveIdentityCache() {
+    private func saveIdentityCache() {
         // Mark that we need to save
         pendingSave = true
         
@@ -201,25 +238,7 @@ final class SecureIdentityStateManager {
     // 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
@@ -301,23 +320,12 @@ final class SecureIdentityStateManager {
         }
     }
 
-    /// Retrieve cryptographic identity by fingerprint
-    func getCryptographicIdentity(for fingerprint: String) -> CryptographicIdentity? {
-        queue.sync { cryptographicIdentities[fingerprint] }
-    }
-
     /// Find cryptographic identities whose fingerprint prefix matches a peerID (16-hex) short ID
-    func getCryptoIdentitiesByPeerIDPrefix(_ peerID: String) -> [CryptographicIdentity] {
+    func getCryptoIdentitiesByPeerIDPrefix(_ peerID: PeerID) -> [CryptographicIdentity] {
         queue.sync {
             // Defensive: ensure hex and correct length
-            guard peerID.count == 16, peerID.allSatisfy({ $0.isHexDigit }) else { return [] }
-            return cryptographicIdentities.values.filter { $0.fingerprint.hasPrefix(peerID) }
-        }
-    }
-    
-    func getAllSocialIdentities() -> [SocialIdentity] {
-        queue.sync {
-            return Array(cache.socialIdentities.values)
+            guard peerID.isShort else { return [] }
+            return cryptographicIdentities.values.filter { $0.fingerprint.hasPrefix(peerID.id) }
         }
     }
     
@@ -447,7 +455,7 @@ final class SecureIdentityStateManager {
     
     // 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,
@@ -457,7 +465,7 @@ final class SecureIdentityStateManager {
         }
     }
     
-    func updateHandshakeState(peerID: String, state: HandshakeState) {
+    func updateHandshakeState(peerID: PeerID, state: HandshakeState) {
         queue.async(flags: .barrier) {
             self.ephemeralSessions[peerID]?.handshakeState = state
             
@@ -469,53 +477,6 @@ final 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() {
@@ -525,7 +486,6 @@ final class SecureIdentityStateManager {
             self.cache = IdentityCache()
             self.ephemeralSessions.removeAll()
             self.cryptographicIdentities.removeAll()
-            self.pendingActions.removeAll()
             
             // Delete from keychain
             let deleted = self.keychain.deleteIdentityKey(forKey: self.cacheKey)
@@ -533,10 +493,9 @@ final class SecureIdentityStateManager {
         }
     }
     
-    func removeEphemeralSession(peerID: String) {
+    func removeEphemeralSession(peerID: PeerID) {
         queue.async(flags: .barrier) {
             self.ephemeralSessions.removeValue(forKey: peerID)
-            self.pendingActions.removeValue(forKey: peerID)
         }
     }
     

bitchat/Info.plist

@@ -37,6 +37,10 @@
 	<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>

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 +1,92 @@
+//
+// 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
+    
+    init(type: UInt8, senderID: Data, recipientID: Data?, timestamp: UInt64, payload: Data, signature: Data?, ttl: UInt8, version: UInt8 = 1) {
+        self.version = version
+        self.type = type
+        self.senderID = senderID
+        self.recipientID = recipientID
+        self.timestamp = timestamp
+        self.payload = payload
+        self.signature = signature
+        self.ttl = ttl
+    }
+    
+    // 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
+    }
+    
+    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
+        )
+        return BinaryProtocol.encode(unsignedPacket)
+    }
+    
+    static func from(_ data: Data) -> BitchatPacket? {
+        BinaryProtocol.decode(data)
+    }
+}

bitchat/Models/BitchatPeer.swift

@@ -2,8 +2,8 @@ import Foundation
 import CoreBluetooth
 
 /// Represents a peer in the BitChat network with all associated metadata
-struct BitchatPeer: Identifiable, Equatable {
-    let id: String // Hex-encoded peer ID
+struct BitchatPeer: Equatable {
+    let peerID: PeerID // Hex-encoded peer ID
     let noisePublicKey: Data
     let nickname: String
     let lastSeen: Date
@@ -51,7 +51,7 @@ struct BitchatPeer: Identifiable, Equatable {
     
     // Display helpers
     var displayName: String {
-        nickname.isEmpty ? String(id.prefix(8)) : nickname
+        nickname.isEmpty ? String(peerID.id.prefix(8)) : nickname
     }
     
     var statusIcon: String {
@@ -73,14 +73,14 @@ struct BitchatPeer: Identifiable, Equatable {
     
     // Initialize from mesh service data
     init(
-        id: String,
+        peerID: PeerID,
         noisePublicKey: Data,
         nickname: String,
         lastSeen: Date = Date(),
         isConnected: Bool = false,
         isReachable: Bool = false
     ) {
-        self.id = id
+        self.peerID = peerID
         self.noisePublicKey = noisePublicKey
         self.nickname = nickname
         self.lastSeen = lastSeen
@@ -93,8 +93,6 @@ struct BitchatPeer: Identifiable, Equatable {
     }
     
     static func == (lhs: BitchatPeer, rhs: BitchatPeer) -> Bool {
-        lhs.id == rhs.id
+        lhs.peerID == rhs.peerID
     }
 }
-
-//

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 +1,207 @@
+//
+// 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
+    }
+}
+
+// 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

@@ -1,357 +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
-final 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
-    private let establishedSessionTTL: TimeInterval = 300.0 // 5 minutes - sessions older than this can be cleaned up
-    private let maxEstablishedSessions = 50 // Limit total established sessions
-    
-    // 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.warning("Forcing new handshake with \(remotePeerID) - previous stuck in initiating", category: .handshake)
-                            return true
-                        }
-                    default:
-                        break
-                    }
-                }
-                
-                SecureLogger.debug("Already in active handshake with \(remotePeerID), state: \(state)", category: .handshake)
-                return false
-            }
-            
-            // Check role
-            let role = determineHandshakeRole(myPeerID: myPeerID, remotePeerID: remotePeerID)
-            if role != .initiator {
-                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.info("Recording handshake initiation with \(peerID), attempt \(attempt)", category: .handshake)
-        }
-    }
-    
-    /// Record that we're responding to a handshake
-    func recordHandshakeResponse(peerID: String) {
-        handshakeQueue.async(flags: .barrier) {
-            self.handshakeStates[peerID] = .responding(since: Date())
-            SecureLogger.info("Recording handshake response to \(peerID)", category: .handshake)
-        }
-    }
-    
-    /// Record successful handshake completion
-    func recordHandshakeSuccess(peerID: String) {
-        handshakeQueue.async(flags: .barrier) {
-            self.handshakeStates[peerID] = .established(since: Date())
-            SecureLogger.info("Handshake successfully established with \(peerID)", category: .handshake)
-        }
-    }
-    
-    /// 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.warning("Handshake failed with \(peerID): \(reason), canRetry: \(canRetry)", category: .handshake)
-        }
-    }
-    
-    /// 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.debug("Rejecting handshake from \(remotePeerID) - already established", category: .handshake)
-                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.warning("Accepting handshake from \(remotePeerID) despite being initiator (race condition recovery)", category: .handshake)
-                    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.debug("Reset handshake state for \(peerID)", category: .handshake)
-        }
-    }
-    
-    /// Clean up stale handshake states and old established sessions
-    func cleanupStaleHandshakes(staleTimeout: TimeInterval = 30.0) -> [String] {
-        return handshakeQueue.sync {
-            let now = Date()
-            var stalePeerIDs: [String] = []
-            var establishedSessions: [(peerID: String, since: Date)] = []
-            
-            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
-                    }
-                case .established(let since):
-                    // Track established sessions for potential cleanup
-                    establishedSessions.append((peerID, since))
-                    // Clean up very old established sessions
-                    if now.timeIntervalSince(since) > establishedSessionTTL {
-                        isStale = true
-                    }
-                default:
-                    break
-                }
-                
-                if isStale {
-                    stalePeerIDs.append(peerID)
-                    SecureLogger.warning("Found stale handshake state for \(peerID): \(state)", category: .handshake)
-                }
-            }
-            
-            // If we have too many established sessions, clean up the oldest ones
-            if establishedSessions.count > maxEstablishedSessions {
-                // Sort by age (oldest first)
-                let sortedSessions = establishedSessions.sorted { $0.since < $1.since }
-                let sessionsToRemove = sortedSessions.count - maxEstablishedSessions
-                
-                for i in 0..<sessionsToRemove {
-                    let peerID = sortedSessions[i].peerID
-                    stalePeerIDs.append(peerID)
-                    SecureLogger.info("Removing old established session for \(peerID) to maintain session limit", category: .handshake)
-                }
-            }
-            
-            // Clean up stale states
-            for peerID in stalePeerIDs {
-                handshakeStates.removeValue(forKey: peerID)
-            }
-            
-            if !stalePeerIDs.isEmpty {
-                SecureLogger.info("Cleaned up \(stalePeerIDs.count) stale handshake states", category: .handshake)
-            }
-            
-            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.debug("=== Handshake States ===", category: .handshake)
-            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.debug("  \(peerID): \(stateDesc)", category: .handshake)
-            }
-            SecureLogger.debug("========================", category: .handshake)
-        }
-    }
-    
-    /// Clear all handshake states - used during panic mode
-    func clearAllHandshakeStates() {
-        handshakeQueue.async(flags: .barrier) {
-            SecureLogger.warning("Clearing all handshake states for panic mode", category: .handshake)
-            self.handshakeStates.removeAll()
-            self.processedHandshakeMessages.removeAll()
-        }
-    }
-}

bitchat/Noise/NoiseProtocol.swift

@@ -77,6 +77,7 @@
 /// - Noise Specification: http://www.noiseprotocol.org/noise.html
 ///
 
+import BitLogger
 import Foundation
 import CryptoKit
 
@@ -396,7 +397,7 @@ final 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
     }
@@ -409,7 +410,7 @@ final class NoiseSymmetricState {
     }
     
     func mixHash(_ data: Data) {
-        hash = Data(SHA256.hash(data: hash + data))
+        hash = (hash + data).sha256Hash()
     }
     
     func mixKeyAndHash(_ inputKeyMaterial: Data) {
@@ -490,6 +491,7 @@ final class NoiseSymmetricState {
 final class NoiseHandshakeState {
     private let role: NoiseRole
     private let pattern: NoisePattern
+    private let keychain: KeychainManagerProtocol
     private var symmetricState: NoiseSymmetricState
     
     // Keys
@@ -505,9 +507,16 @@ final 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 {
@@ -578,7 +587,7 @@ final class NoiseHandshakeState {
                 var sharedData = shared.withUnsafeBytes { Data($0) }
                 symmetricState.mixKey(sharedData)
                 // Clear sensitive shared secret
-                KeychainManager.secureClear(&sharedData)
+                keychain.secureClear(&sharedData)
                 
             case .es:
                 // DH(ephemeral, static) - direction depends on role
@@ -626,7 +635,7 @@ final class NoiseHandshakeState {
                 var sharedData = shared.withUnsafeBytes { Data($0) }
                 symmetricState.mixKey(sharedData)
                 // Clear sensitive shared secret
-                KeychainManager.secureClear(&sharedData)
+                keychain.secureClear(&sharedData)
             }
         }
         
@@ -714,7 +723,7 @@ final class NoiseHandshakeState {
                 var sharedData = shared.withUnsafeBytes { Data($0) }
                 symmetricState.mixKey(sharedData)
                 // Clear sensitive shared secret
-                KeychainManager.secureClear(&sharedData)
+                keychain.secureClear(&sharedData)
             } else {
                 guard let localStatic = localStaticPrivate,
                       let remoteEphemeral = remoteEphemeralPublic else {
@@ -724,7 +733,7 @@ final class NoiseHandshakeState {
                 var sharedData = shared.withUnsafeBytes { Data($0) }
                 symmetricState.mixKey(sharedData)
                 // Clear sensitive shared secret
-                KeychainManager.secureClear(&sharedData)
+                keychain.secureClear(&sharedData)
             }
             
         case .se:
@@ -737,7 +746,7 @@ final class NoiseHandshakeState {
                 var sharedData = shared.withUnsafeBytes { Data($0) }
                 symmetricState.mixKey(sharedData)
                 // Clear sensitive shared secret
-                KeychainManager.secureClear(&sharedData)
+                keychain.secureClear(&sharedData)
             } else {
                 guard let localEphemeral = localEphemeralPrivate,
                       let remoteStatic = remoteStaticPublic else {
@@ -747,7 +756,7 @@ final class NoiseHandshakeState {
                 var sharedData = shared.withUnsafeBytes { Data($0) }
                 symmetricState.mixKey(sharedData)
                 // Clear sensitive shared secret
-                KeychainManager.secureClear(&sharedData)
+                keychain.secureClear(&sharedData)
             }
             
         case .ss:
@@ -758,7 +767,7 @@ final class NoiseHandshakeState {
             let shared = try localStatic.sharedSecretFromKeyAgreement(with: remoteStatic)
             symmetricState.mixKey(shared.withUnsafeBytes { Data($0) })
             
-        default:
+        case .e, .s:
             break
         }
     }

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

@@ -1,223 +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 using unified validator
-    static func validatePeerID(_ peerID: String) -> Bool {
-        return InputValidator.validatePeerID(peerID)
-    }
-}
-
-// MARK: - Enhanced Noise Session with Security
-
-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
-}
-
-// MARK: - Rate Limiter
-
-final 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.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: 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.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: 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

@@ -6,36 +6,14 @@
 // For more information, see <https://unlicense.org>
 //
 
+import BitLogger
 import Foundation
 import CryptoKit
 
-// 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?
@@ -52,9 +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
     }
@@ -71,6 +56,7 @@ class NoiseSession {
             handshakeState = NoiseHandshakeState(
                 role: role,
                 pattern: .XX,
+                keychain: keychain,
                 localStaticKey: localStaticKey,
                 remoteStaticKey: nil
             )
@@ -98,6 +84,7 @@ class NoiseSession {
                 handshakeState = NoiseHandshakeState(
                     role: role,
                     pattern: .XX,
+                    keychain: keychain,
                     localStaticKey: localStaticKey,
                     remoteStaticKey: nil
                 )
@@ -130,7 +117,7 @@ class NoiseSession {
                 handshakeState = nil // Clear handshake state
                 
                 SecureLogger.debug("NoiseSession[\(peerID)]: Handshake complete (no response needed), transitioning to established")
-                SecureLogger.info(.handshakeCompleted(peerID: peerID))
+                SecureLogger.info(.handshakeCompleted(peerID: peerID.id))
                 
                 return nil
             } else {
@@ -156,7 +143,7 @@ class NoiseSession {
                     handshakeState = nil // Clear handshake state
                     
                     SecureLogger.debug("NoiseSession[\(peerID)]: Handshake complete after writing response, transitioning to established")
-                    SecureLogger.info(.handshakeCompleted(peerID: peerID))
+                    SecureLogger.info(.handshakeCompleted(peerID: peerID.id))
                 }
                 
                 return response
@@ -209,12 +196,6 @@ class NoiseSession {
         }
     }
     
-    func getHandshakeHash() -> Data? {
-        return sessionQueue.sync {
-            return handshakeHash
-        }
-    }
-    
     func reset() {
         sessionQueue.sync(flags: .barrier) {
             let wasEstablished = state == .established
@@ -230,246 +211,19 @@ class NoiseSession {
             // Clear sent handshake messages
             for i in 0..<sentHandshakeMessages.count {
                 var message = sentHandshakeMessages[i]
-                KeychainManager.secureClear(&message)
+                keychain.secureClear(&message)
             }
             sentHandshakeMessages.removeAll()
             
             // Clear handshake hash
             if var hash = handshakeHash {
-                KeychainManager.secureClear(&hash)
+                keychain.secureClear(&hash)
             }
             handshakeHash = nil
             
             if wasEstablished {
-                SecureLogger.info(.sessionExpired(peerID: peerID))
+                SecureLogger.info(.sessionExpired(peerID: peerID.id))
             }
         }
     }
 }
-
-// MARK: - Session Manager
-
-final 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] {
-                if session.isEstablished() {
-                    SecureLogger.info(.sessionExpired(peerID: peerID))
-                }
-                // Clear sensitive data before removing
-                session.reset()
-            }
-            _ = sessions.removeValue(forKey: peerID)
-        }
-    }
-    
-    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.error(.handshakeFailed(peerID: peerID, error: error.localizedDescription))
-                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.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,
-                    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, error: error.localizedDescription))
-                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

@@ -1,4 +1,11 @@
+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
@@ -10,19 +17,32 @@ final class GeoRelayDirectory {
     }
 
     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 // 24h
+    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() {
-        // Load cached or bundled data synchronously
-        self.entries = self.loadLocalEntries()
-        // Fire-and-forget remote refresh if stale
+        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)
@@ -31,52 +51,148 @@ final class GeoRelayDirectory {
 
     /// 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 else { return [] }
-        let sorted = entries
-            .sorted { a, b in
-                haversineKm(lat, lon, a.lat, a.lon) < haversineKm(lat, lon, b.lat, b.lon)
+        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()
             }
-            .prefix(count)
-        return sorted.map { "wss://\($0.host)" }
+        }
+
+        return best.map { "wss://\($0.entry.host)" }
     }
 
     // MARK: - Remote Fetch
-    func prefetchIfNeeded() {
+    func prefetchIfNeeded(force: Bool = false) {
+        guard !isFetching else { return }
+
         let now = Date()
         let last = UserDefaults.standard.object(forKey: lastFetchKey) as? Date ?? .distantPast
-        guard now.timeIntervalSince(last) >= fetchInterval else { return }
+
+        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() {
-        let req = URLRequest(url: remoteURL, cachePolicy: .reloadIgnoringLocalCacheData, timeoutInterval: 15)
-        // Ensure Tor readiness before fetching (fail-closed by default)
-        Task.detached {
+        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 {
-                SecureLogger.warning("GeoRelayDirectory: Tor not ready; skipping remote fetch (fail-closed)", category: .session)
+                await self.handleFetchFailure(.torNotReady)
                 return
             }
-            let task = TorURLSession.shared.session.dataTask(with: req) { [weak self] data, _, error in
-                guard let self = self else { return }
-                if let data = data, error == nil, let text = String(data: data, encoding: .utf8) {
-                    let parsed = GeoRelayDirectory.parseCSV(text)
-                    if !parsed.isEmpty {
-                        Task { @MainActor in
-                            self.entries = parsed
-                            self.persistCache(text)
-                            UserDefaults.standard.set(Date(), forKey: self.lastFetchKey)
-                            SecureLogger.info("GeoRelayDirectory: refreshed \(parsed.count) relays from remote", category: .session)
-                        }
-                        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
                 }
-                SecureLogger.warning("GeoRelayDirectory: remote fetch failed; keeping local entries", category: .session)
+
+                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))
             }
-            task.resume()
         }
     }
 
+    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 {
@@ -89,30 +205,35 @@ final class GeoRelayDirectory {
     // MARK: - Loading
     private func loadLocalEntries() -> [Entry] {
         // Prefer cached file if present
-        if let cache = self.cacheURL(),
+        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) {
+            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 []
     }
@@ -120,7 +241,6 @@ final class GeoRelayDirectory {
     nonisolated static func parseCSV(_ text: String) -> [Entry] {
         var result: Set<Entry> = []
         let lines = text.split(whereSeparator: { $0.isNewline })
-        // Skip header if present
         for (idx, raw) in lines.enumerated() {
             let line = raw.trimmingCharacters(in: .whitespacesAndNewlines)
             if line.isEmpty { continue }
@@ -141,11 +261,76 @@ final class GeoRelayDirectory {
 
     private func cacheURL() -> URL? {
         do {
-            let base = try FileManager.default.url(for: .applicationSupportDirectory, in: .userDomainMask, appropriateFor: nil, create: true)
+            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 }
+        } 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)
     }
 }
 

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

@@ -4,7 +4,7 @@ import Foundation
 
 struct NostrEmbeddedBitChat {
     /// Build a `bitchat1:` base64url-encoded BitChat packet carrying a private message for Nostr DMs.
-    static func encodePMForNostr(content: String, messageID: String, recipientPeerID: String, senderPeerID: String) -> String? {
+    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 }
@@ -14,12 +14,12 @@ struct NostrEmbeddedBitChat {
         payload.append(tlv)
 
         // Determine 8-byte recipient ID to embed
-        let recipientIDHex: String = normalizeRecipientPeerID(recipientPeerID)
+        let recipientID = normalizeRecipientPeerID(recipientPeerID)
 
         let packet = BitchatPacket(
             type: MessageType.noiseEncrypted.rawValue,
-            senderID: Data(hexString: senderPeerID) ?? Data(),
-            recipientID: Data(hexString: recipientIDHex),
+            senderID: Data(hexString: senderPeerID.id) ?? Data(),
+            recipientID: Data(hexString: recipientID.id),
             timestamp: UInt64(Date().timeIntervalSince1970 * 1000),
             payload: payload,
             signature: nil,
@@ -31,18 +31,18 @@ struct NostrEmbeddedBitChat {
     }
 
     /// Build a `bitchat1:` base64url-encoded BitChat packet carrying a delivery/read ack for Nostr DMs.
-    static func encodeAckForNostr(type: NoisePayloadType, messageID: String, recipientPeerID: String, senderPeerID: String) -> String? {
+    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 recipientIDHex: String = normalizeRecipientPeerID(recipientPeerID)
+        let recipientID = normalizeRecipientPeerID(recipientPeerID)
 
         let packet = BitchatPacket(
             type: MessageType.noiseEncrypted.rawValue,
-            senderID: Data(hexString: senderPeerID) ?? Data(),
-            recipientID: Data(hexString: recipientIDHex),
+            senderID: Data(hexString: senderPeerID.id) ?? Data(),
+            recipientID: Data(hexString: recipientID.id),
             timestamp: UInt64(Date().timeIntervalSince1970 * 1000),
             payload: payload,
             signature: nil,
@@ -54,7 +54,7 @@ struct NostrEmbeddedBitChat {
     }
 
     /// Build a `bitchat1:` ACK (delivered/read) without an embedded recipient peer ID (geohash DMs).
-    static func encodeAckForNostrNoRecipient(type: NoisePayloadType, messageID: String, senderPeerID: String) -> String? {
+    static func encodeAckForNostrNoRecipient(type: NoisePayloadType, messageID: String, senderPeerID: PeerID) -> String? {
         guard type == .delivered || type == .readReceipt else { return nil }
 
         var payload = Data([type.rawValue])
@@ -62,7 +62,7 @@ struct NostrEmbeddedBitChat {
 
         let packet = BitchatPacket(
             type: MessageType.noiseEncrypted.rawValue,
-            senderID: Data(hexString: senderPeerID) ?? Data(),
+            senderID: Data(hexString: senderPeerID.id) ?? Data(),
             recipientID: nil,
             timestamp: UInt64(Date().timeIntervalSince1970 * 1000),
             payload: payload,
@@ -75,7 +75,7 @@ struct NostrEmbeddedBitChat {
     }
 
     /// Build a `bitchat1:` payload without an embedded recipient peer ID (used for geohash DMs).
-    static func encodePMForNostrNoRecipient(content: String, messageID: String, senderPeerID: String) -> String? {
+    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 }
 
@@ -84,7 +84,7 @@ struct NostrEmbeddedBitChat {
 
         let packet = BitchatPacket(
             type: MessageType.noiseEncrypted.rawValue,
-            senderID: Data(hexString: senderPeerID) ?? Data(),
+            senderID: Data(hexString: senderPeerID.id) ?? Data(),
             recipientID: nil,
             timestamp: UInt64(Date().timeIntervalSince1970 * 1000),
             payload: payload,
@@ -96,11 +96,11 @@ struct NostrEmbeddedBitChat {
         return "bitchat1:" + base64URLEncode(data)
     }
 
-    private static func normalizeRecipientPeerID(_ recipientPeerID: String) -> String {
-        if let maybeData = Data(hexString: recipientPeerID) {
+    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 PeerIDUtils.derivePeerID(fromPublicKey: maybeData)
+                return PeerID(publicKey: maybeData)
             } else if maybeData.count == 8 {
                 // Already an 8-byte peer ID
                 return recipientPeerID

bitchat/Nostr/NostrIdentity.swift

@@ -1,50 +1,5 @@
 import Foundation
-import CryptoKit
 import P256K
-import Security
-
-// Keychain helper for secure storage
-struct KeychainHelper {
-    static 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)
-    }
-    
-    static 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
-    }
-    
-    static 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)
-    }
-}
 
 /// Manages Nostr identity (secp256k1 keypair) for NIP-17 private messaging
 struct NostrIdentity: Codable {
@@ -103,251 +58,3 @@ struct NostrIdentity: Codable {
         return publicKey.hexEncodedString()
     }
 }
-
-/// Bridge between Noise and Nostr identities
-struct NostrIdentityBridge {
-    private static let keychainService = "chat.bitchat.nostr"
-    private static let currentIdentityKey = "nostr-current-identity"
-    private static let deviceSeedKey = "nostr-device-seed"
-    // In-memory cache to avoid transient keychain access issues
-    private static var deviceSeedCache: Data?
-    
-    /// Get or create the current Nostr identity
-    static func getCurrentNostrIdentity() throws -> NostrIdentity? {
-        // Check if we already have a Nostr identity
-        if let existingData = KeychainHelper.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)
-        KeychainHelper.save(key: currentIdentityKey, data: data, service: keychainService)
-        
-        return nostrIdentity
-    }
-    
-    /// Associate a Nostr identity with a Noise public key (for favorites)
-    static func associateNostrIdentity(_ nostrPubkey: String, with noisePublicKey: Data) {
-        let key = "nostr-noise-\(noisePublicKey.base64EncodedString())"
-        if let data = nostrPubkey.data(using: .utf8) {
-            KeychainHelper.save(key: key, data: data, service: keychainService)
-        }
-    }
-    
-    /// Get Nostr public key associated with a Noise public key
-    static func getNostrPublicKey(for noisePublicKey: Data) -> String? {
-        let key = "nostr-noise-\(noisePublicKey.base64EncodedString())"
-        guard let data = KeychainHelper.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
-    static func clearAllAssociations() {
-        // Delete current Nostr identity
-        KeychainHelper.delete(key: currentIdentityKey, service: keychainService)
-        KeychainHelper.delete(key: deviceSeedKey, service: keychainService)
-        
-        // Note: We can't efficiently delete all noise-nostr associations 
-        // without tracking them, but they'll be orphaned and eventually cleaned up
-        // The important part is deleting the current identity so a new one is generated
-    }
-
-    // MARK: - Per-Geohash Identities (Location Channels)
-
-    /// Returns a stable device seed used to derive unlinkable per-geohash identities.
-    /// Stored only on device keychain.
-    private static func getOrCreateDeviceSeed() -> Data {
-        if let cached = deviceSeedCache { return cached }
-        if let existing = KeychainHelper.load(key: deviceSeedKey, service: keychainService) {
-            // Migrate to AfterFirstUnlockThisDeviceOnly for stability during lock
-            KeychainHelper.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
-        KeychainHelper.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.
-    static func deriveIdentity(forGeohash geohash: String) throws -> NostrIdentity {
-        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 = CryptoKit.HMAC<CryptoKit.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) {
-                return identity
-            }
-        }
-        // As a final fallback, hash the seed+msg and try again
-        var combined = Data()
-        combined.append(seed)
-        combined.append(msg)
-        let fallback = Data(CryptoKit.SHA256.hash(data: combined))
-        return try NostrIdentity(privateKeyData: fallback)
-    }
-}
-
-// 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
-    }
-}
-
-// Data hex encoding extension moved to BinaryEncodingUtils.swift to avoid duplication

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

@@ -1,3 +1,4 @@
+import BitLogger
 import Foundation
 import CryptoKit
 import P256K
@@ -123,6 +124,28 @@ struct NostrProtocol {
         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
     
@@ -498,10 +521,7 @@ struct NostrEvent: Codable {
         ] as [Any]
         
         let data = try JSONSerialization.data(withJSONObject: serialized, options: [.withoutEscapingSlashes])
-        let hash = CryptoKit.SHA256.hash(data: data)
-        let hashData = Data(hash)
-        let hashHex = hash.compactMap { String(format: "%02x", $0) }.joined()
-        return (hashHex, hashData)
+        return (data.sha256Fingerprint(), data.sha256Hash())
     }
     
     func jsonString() throws -> String {

bitchat/Nostr/NostrRelayManager.swift

@@ -1,6 +1,8 @@
+import BitLogger
 import Foundation
 import Network
 import Combine
+import Tor
 
 /// Manages WebSocket connections to Nostr relays
 @MainActor
@@ -34,10 +36,14 @@ final class NostrRelayManager: ObservableObject {
         "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)
@@ -45,6 +51,14 @@ final class NostrRelayManager: ObservableObject {
     // 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.
@@ -56,6 +70,8 @@ final class NostrRelayManager: ObservableObject {
     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
@@ -69,27 +85,55 @@ final class NostrRelayManager: ObservableObject {
     private var connectionGeneration: Int = 0
     
     init() {
-        // Initialize with default relays
-        self.relays = Self.defaultRelays.map { Relay(url: $0) }
+        hasMutualFavorites = !FavoritesPersistenceService.shared.mutualFavorites.isEmpty
+        hasLocationPermission = LocationChannelManager.shared.permissionState == .authorized
+        applyDefaultRelayPolicy(force: true)
         // Deterministic JSON shape for outbound requests
         self.encoder.outputFormatting = .sortedKeys
+        FavoritesPersistenceService.shared.$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() {
-        // 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)
+        // 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)
+            }
         }
     }
     
@@ -108,7 +152,11 @@ final class NostrRelayManager: ObservableObject {
     
     /// Ensure connections exist to the given relay URLs (idempotent).
     func ensureConnections(to relayUrls: [String]) {
-        if TorManager.shared.torEnforced && !TorManager.shared.isReady {
+        // 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 }
@@ -117,20 +165,21 @@ final class NostrRelayManager: ObservableObject {
             }
             return
         }
-        let existing = Set(relays.map { $0.url })
-        for url in Set(relayUrls) {
-            if !existing.contains(url) {
-                relays.append(Relay(url: url))
-            }
-            if connections[url] == nil {
-                connectToRelay(url)
-            }
+        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) {
-        if TorManager.shared.torEnforced && !TorManager.shared.isReady {
+        // 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 }
@@ -139,7 +188,9 @@ final class NostrRelayManager: ObservableObject {
             }
             return
         }
-        let targetRelays = relayUrls ?? Self.defaultRelays
+        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
@@ -201,8 +252,11 @@ final class NostrRelayManager: ObservableObject {
         filter: NostrFilter,
         id: String = UUID().uuidString,
         relayUrls: [String]? = nil,
-        handler: @escaping (NostrEvent) -> Void
+        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 {
@@ -211,7 +265,7 @@ final class NostrRelayManager: ObservableObject {
             }
         }
         subscribeCoalesce[id] = now
-        if TorManager.shared.torEnforced && !TorManager.shared.isReady {
+        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 }
@@ -239,17 +293,38 @@ final class NostrRelayManager: ObservableObject {
             
             // Target specific relays if provided; else default. Filter permanently failed relays.
             let baseUrls = relayUrls ?? Self.defaultRelays
-            let urls = baseUrls.filter { !isPermanentlyFailed($0) }
+            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 urls {
+            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)
@@ -263,6 +338,55 @@ final class NostrRelayManager: ObservableObject {
             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) {
@@ -291,13 +415,15 @@ final class NostrRelayManager: ObservableObject {
     // 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 TorManager.shared.torEnforced && !TorManager.shared.isForeground() {
+        if shouldUseTor && TorManager.shared.torEnforced && !TorManager.shared.isForeground() {
             return
         }
         
@@ -312,7 +438,7 @@ final class NostrRelayManager: ObservableObject {
         // Attempting to connect to Nostr relay via the proxied session
         
         // If Tor is enforced but not ready, delay connection until it is.
-        if TorManager.shared.torEnforced && !TorManager.shared.isReady {
+        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()
@@ -418,9 +544,17 @@ final class NostrRelayManager: ObservableObject {
             } else {
                 SecureLogger.warning("⚠️ No handler for subscription \(subId)", category: .session)
             }
-        case .eose:
-            // No-op for now
-            break
+        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)
@@ -489,6 +623,13 @@ final class NostrRelayManager: ObservableObject {
     }
     
     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)
@@ -755,6 +896,26 @@ struct NostrFilter: Encodable {
         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

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
@@ -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 = ""

bitchat/Protocols/BinaryProtocol.swift

@@ -22,11 +22,11 @@
 ///
 /// ## Wire Format
 /// ```
-/// Header (Fixed 13 bytes):
-/// +--------+------+-----+-----------+-------+----------------+
-/// |Version | Type | TTL | Timestamp | Flags | PayloadLength  |
-/// |1 byte  |1 byte|1byte| 8 bytes   | 1 byte| 2 bytes        |
-/// +--------+------+-----+-----------+-------+----------------+
+/// 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:
 /// +----------+-------------+---------+------------+
@@ -52,7 +52,7 @@
 /// ## Flag Bits
 /// - Bit 0: Has recipient ID (directed message)
 /// - Bit 1: Has signature (authenticated message)
-/// - Bit 2: Is compressed (LZ4 compression applied)
+/// - Bit 2: Is compressed (zlib compression applied)
 /// - Bits 3-7: Reserved for future use
 ///
 /// ## Size Constraints
@@ -89,6 +89,7 @@
 ///
 
 import Foundation
+import BitLogger
 
 extension Data {
     func trimmingNullBytes() -> Data {
@@ -105,10 +106,32 @@ extension Data {
 /// 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
@@ -118,70 +141,69 @@ struct BinaryProtocol {
     
     // Encode BitchatPacket to binary format
     static func encode(_ packet: BitchatPacket, padding: Bool = true) -> Data? {
-        var data = Data()
-        
-        
-        // Try to compress payload if beneficial
+        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
-        // Reserve capacity to reduce reallocations. Estimate base size conservatively.
-        // header(13) + sender(8) + opt recipient(8) + opt originalSize(2) + payload + opt signature(64) + up to 255 pad
-        let estimatedPayload = payload.count + (isCompressed ? 2 : 0)
-        let estimated = headerSize + senderIDSize + (packet.recipientID == nil ? 0 : recipientIDSize) + estimatedPayload + (packet.signature == nil ? 0 : signatureSize) + 255
-        data.reserveCapacity(estimated)
-        data.append(packet.version)
+
+        let lengthFieldBytes = lengthFieldSize(for: version)
+        let originalSizeFieldBytes = isCompressed ? lengthFieldBytes : 0
+        let payloadDataSize = 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 }
         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)
@@ -189,30 +211,30 @@ struct BinaryProtocol {
                 data.append(Data(repeating: 0, count: recipientIDSize - recipientBytes.count))
             }
         }
-        
-        // Payload (with original size prepended if compressed)
+
         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
+
         if padding {
             let optimalSize = MessagePadding.optimalBlockSize(for: data.count)
-            let paddedData = MessagePadding.pad(data, toSize: optimalSize)
-            return paddedData
-        } else {
-            // Caller explicitly requested no padding (e.g., BLE write path)
-            return data
+            return MessagePadding.pad(data, toSize: optimalSize)
         }
+        return data
     }
     
     // Decode binary data to BitchatPacket
@@ -227,87 +249,113 @@ struct BinaryProtocol {
 
     // Core decoding implementation used by decode(_:) with and without padding removal
     private static func decodeCore(_ raw: Data) -> BitchatPacket? {
-        // Minimum size: header + senderID
-        guard raw.count >= headerSize + senderIDSize else { return nil }
+        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 }
-            // Read single byte
             func read8() -> UInt8? {
                 guard require(1) else { return nil }
-                let v = base.advanced(by: offset).assumingMemoryBound(to: UInt8.self).pointee
+                let value = base.advanced(by: offset).assumingMemoryBound(to: UInt8.self).pointee
                 offset += 1
-                return v
+                return value
             }
-            // Read big-endian 16-bit
             func read16() -> UInt16? {
                 guard require(2) else { return nil }
-                let p = base.advanced(by: offset).assumingMemoryBound(to: UInt8.self)
-                let v = (UInt16(p[0]) << 8) | UInt16(p[1])
+                let ptr = base.advanced(by: offset).assumingMemoryBound(to: UInt8.self)
+                let value = (UInt16(ptr[0]) << 8) | UInt16(ptr[1])
                 offset += 2
-                return v
+                return value
+            }
+            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
             }
-            // Copy N bytes into Data
             func readData(_ n: Int) -> Data? {
                 guard require(n) else { return nil }
                 let ptr = base.advanced(by: offset)
-                let d = Data(bytes: ptr, count: n)
+                let data = Data(bytes: ptr, count: n)
                 offset += n
-                return d
+                return data
             }
 
-            // Version
-            guard let version = read8(), version == 1 else { return nil }
-            guard let type = read8() else { return nil }
-            guard let ttl = read8() else { return nil }
+            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 }
 
-            // Timestamp 8 bytes BE
-            guard require(8) else { return nil }
-            var ts: UInt64 = 0
+            guard let type = read8(), let ttl = read8() else { return nil }
+
+            var timestamp: UInt64 = 0
             for _ in 0..<8 {
-                guard let b = read8() else { return nil }
-                ts = (ts << 8) | UInt64(b)
+                guard let byte = read8() else { return nil }
+                timestamp = (timestamp << 8) | UInt64(byte)
             }
 
-            // Flags
             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
 
-            // Payload length
-            guard let payloadLen = read16(), payloadLen <= 65535 else { return nil }
+            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 }
 
-            // SenderID
             guard let senderID = readData(senderIDSize) else { return nil }
 
-            // Recipient
             var recipientID: Data? = nil
             if hasRecipient {
                 recipientID = readData(recipientIDSize)
                 if recipientID == nil { return nil }
             }
 
-            // Payload
             let payload: Data
             if isCompressed {
-                // Need original size (2 bytes)
-                guard let origSize16 = read16() else { return nil }
-                let originalSize = Int(origSize16)
-                guard originalSize >= 0 && originalSize <= 1_048_576 else { return nil }
-                let compSize = Int(payloadLen) - 2
-                guard compSize >= 0, let compressed = readData(compSize) else { return nil }
+                guard payloadLength >= 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)
+                }
+                // Guard to keep decompression bounded to sane BLE payload limits
+                // Use maxFramedFileBytes to account for TLV overhead in file transfer payloads
+                guard originalSize >= 0 && originalSize <= FileTransferLimits.maxFramedFileBytes else { return nil }
+                let compressedSize = payloadLength - lengthFieldBytes
+                guard compressedSize >= 0, let compressed = readData(compressedSize) else { return nil }
+
+                // Validate compression ratio to prevent zip bomb attacks
+                // Primary protection: originalSize capped at 1MB (line 336)
+                // Defense-in-depth: reject extreme ratios (prevents DoS via memory allocation)
+                guard compressedSize > 0 else { return nil }
+                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 let p = readData(Int(payloadLen)) else { return nil }
-                payload = p
+                guard let rawPayload = readData(payloadLength) else { return nil }
+                payload = rawPayload
             }
 
-            // Signature
             var signature: Data? = nil
             if hasSignature {
                 signature = readData(signatureSize)
@@ -320,244 +368,12 @@ struct BinaryProtocol {
                 type: type,
                 senderID: senderID,
                 recipientID: recipientID,
-                timestamp: ts,
+                timestamp: timestamp,
                 payload: payload,
                 signature: signature,
-                ttl: ttl
+                ttl: ttl,
+                version: version
             )
         }
     }
 }
-
-// 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)
-                }
-            }
-        }
-        
-        
-        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
-            }
-        }
-        
-        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: 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
-            }
-        }
-        
-        // 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
-                        }
-                    }
-                }
-            }
-        }
-        
-        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/BitchatProtocol.swift

@@ -59,61 +59,7 @@
 ///
 
 import Foundation
-import CryptoKit
-
-// MARK: - Message Padding
-
-/// 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
-    }
-}
+import CoreBluetooth
 
 // MARK: - Message Types
 
@@ -125,6 +71,7 @@ enum MessageType: UInt8 {
     case announce = 0x01        // "I'm here" with nickname
     case message = 0x02         // Public chat message  
     case leave = 0x03           // "I'm leaving"
+    case requestSync = 0x21     // GCS filter-based sync request (local-only)
     
     // Noise encryption
     case noiseHandshake = 0x10  // Handshake (init or response determined by payload)
@@ -132,15 +79,18 @@ enum MessageType: UInt8 {
     
     // Fragmentation (simplified)
     case fragment = 0x20        // Single fragment type for large messages
+    case fileTransfer = 0x22    // Binary file/audio/image payloads
     
     var description: String {
         switch self {
         case .announce: return "announce"
         case .message: return "message"
         case .leave: return "leave"
+        case .requestSync: return "requestSync"
         case .noiseHandshake: return "noiseHandshake"
         case .noiseEncrypted: return "noiseEncrypted"
         case .fragment: return "fragment"
+        case .fileTransfer: return "fileTransfer"
         }
     }
 }
@@ -181,191 +131,10 @@ enum LazyHandshakeState {
     case failed(Error)         // Handshake failed
 }
 
-//
-
-// MARK: - Core Protocol Structures
-
-/// 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
-    
-    init(type: UInt8, senderID: Data, recipientID: Data?, timestamp: UInt64, payload: Data, signature: Data?, ttl: UInt8) {
-        self.version = 1
-        self.type = type
-        self.senderID = senderID
-        self.recipientID = recipientID
-        self.timestamp = timestamp
-        self.payload = payload
-        self.signature = signature
-        self.ttl = ttl
-    }
-    
-    // Convenience initializer for new binary format
-    init(type: UInt8, ttl: UInt8, senderID: String, payload: Data) {
-        self.version = 1
-        self.type = type
-        // Convert hex string peer ID to binary data (8 bytes)
-        var senderData = Data()
-        var tempID = senderID
-        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
-    }
-    
-    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
-        )
-        return BinaryProtocol.encode(unsignedPacket)
-    }
-    
-    static func from(_ data: Data) -> BitchatPacket? {
-        BinaryProtocol.decode(data)
-    }
-}
-
-//
-
-// MARK: - Read Receipts
-
-// Read receipt structure
-struct ReadReceipt: Codable {
-    let originalMessageID: String
-    let receiptID: String
-    var readerID: String  // Who read it
-    let readerNickname: String
-    let timestamp: Date
-    
-    init(originalMessageID: String, readerID: String, 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: String, 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
-        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 = readerIDData.hexEncodedString()
-        guard InputValidator.validatePeerID(readerID) 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)
-    }
-}
-
-
-//
-
-
 // MARK: - Delivery Status
 
 // Delivery status for messages
-enum DeliveryStatus: Codable, Equatable {
+enum DeliveryStatus: Codable, Equatable, Hashable {
     case sending
     case sent  // Left our device
     case delivered(to: String, at: Date)  // Confirmed by recipient
@@ -391,90 +160,25 @@ enum DeliveryStatus: Codable, Equatable {
     }
 }
 
-// MARK: - Message Model
-
-/// 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: String?
-    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: String? = 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)
-    }
-}
-
-// Equatable conformance for BitchatMessage
-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: - Delegate Protocol
 
 protocol BitchatDelegate: AnyObject {
     func didReceiveMessage(_ message: BitchatMessage)
-    func didConnectToPeer(_ peerID: String)
-    func didDisconnectFromPeer(_ peerID: String)
-    func didUpdatePeerList(_ peers: [String])
-    
+    func didConnectToPeer(_ peerID: PeerID)
+    func didDisconnectFromPeer(_ peerID: PeerID)
+    func didUpdatePeerList(_ peers: [PeerID])
+
     // Optional method to check if a fingerprint belongs to a favorite peer
     func isFavorite(fingerprint: String) -> Bool
-    
+
     func didUpdateMessageDeliveryStatus(_ messageID: String, status: DeliveryStatus)
 
     // Low-level events for better separation of concerns
-    func didReceiveNoisePayload(from peerID: String, type: NoisePayloadType, payload: Data, timestamp: Date)
-    func didReceivePublicMessage(from peerID: String, nickname: String, content: String, timestamp: Date)
+    func didReceiveNoisePayload(from peerID: PeerID, type: NoisePayloadType, payload: Data, timestamp: Date)
+
+    // Bluetooth state updates for user notifications
+    func didUpdateBluetoothState(_ state: CBManagerState)
+    func didReceivePublicMessage(from peerID: PeerID, nickname: String, content: String, timestamp: Date, messageID: String?)
 }
 
 // Provide default implementation to make it effectively optional
@@ -487,45 +191,11 @@ extension BitchatDelegate {
         // Default empty implementation
     }
 
-    func didReceiveNoisePayload(from peerID: String, type: NoisePayloadType, payload: Data, timestamp: Date) {
+    func didReceiveNoisePayload(from peerID: PeerID, type: NoisePayloadType, payload: Data, timestamp: Date) {
         // Default empty implementation
     }
 
-    func didReceivePublicMessage(from peerID: String, nickname: String, content: String, timestamp: Date) {
+    func didReceivePublicMessage(from peerID: PeerID, nickname: String, content: String, timestamp: Date, messageID: String?) {
         // Default empty implementation
     }
 }
-
-// MARK: - Noise Payload Helpers
-
-/// 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/Protocols/Geohash.swift

@@ -10,6 +10,14 @@ enum Geohash {
         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)
@@ -111,4 +119,57 @@ enum Geohash {
         }
         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

@@ -2,6 +2,7 @@ import Foundation
 
 /// Levels of location channels mapped to geohash precisions.
 enum GeohashChannelLevel: CaseIterable, Codable, Equatable {
+    case building
     case block
     case neighborhood
     case city
@@ -11,6 +12,7 @@ enum GeohashChannelLevel: CaseIterable, Codable, Equatable {
     /// 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
@@ -21,20 +23,28 @@ enum GeohashChannelLevel: CaseIterable, Codable, Equatable {
 
     var displayName: String {
         switch self {
-        case .block: return "Block"
-        case .neighborhood: return "Neighborhood"
-        case .city: return "City"
-        case .province: return "Province"
-        case .region: return "Region"
+        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
@@ -46,6 +56,7 @@ extension GeohashChannelLevel {
             }
         } 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
@@ -61,6 +72,7 @@ extension GeohashChannelLevel {
     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")

bitchat/Protocols/PeerID.swift

@@ -1,14 +0,0 @@
-import Foundation
-import CryptoKit
-
-// MARK: - Peer ID Utilities
-
-struct PeerIDUtils {
-    /// Derive the stable 16-hex peer ID from a Noise static public key
-    static func derivePeerID(fromPublicKey publicKey: Data) -> String {
-        let digest = SHA256.hash(data: publicKey)
-        let hex = digest.map { String(format: "%02x", $0) }.joined()
-        return String(hex.prefix(16))
-    }
-}
-

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

@@ -20,10 +20,12 @@ enum CommandResult {
 final class CommandProcessor {
     weak var chatViewModel: ChatViewModel?
     weak var meshService: Transport?
+    private let identityManager: SecureIdentityStateManagerProtocol
     
-    init(chatViewModel: ChatViewModel? = nil, meshService: Transport? = nil) {
+    init(chatViewModel: ChatViewModel? = nil, meshService: Transport? = nil, identityManager: SecureIdentityStateManagerProtocol) {
         self.chatViewModel = chatViewModel
         self.meshService = meshService
+        self.identityManager = identityManager
     }
     
     /// Process a command string
@@ -40,7 +42,7 @@ final class CommandProcessor {
             case .location: return true
             }
         }()
-        let inGeoDM = (chatViewModel?.selectedPrivateChatPeer?.hasPrefix("nostr_") == true)
+        let inGeoDM = chatViewModel?.selectedPrivateChatPeer?.isGeoDM == true
 
         switch cmd {
         case "/m", "/msg":
@@ -63,14 +65,11 @@ final class CommandProcessor {
         case "/unfav":
             if inGeoPublic || inGeoDM { return .error(message: "favorites are only for mesh peers in #mesh") }
             return handleFavorite(args, add: false)
-        //
-        case "/help", "/h":
-            return .error(message: "unknown command: \(cmd)")
         default:
             return .error(message: "unknown command: \(cmd)")
         }
     }
-    
+
     // MARK: - Command Handlers
     
     private func handleMessage(_ args: String) -> CommandResult {
@@ -102,7 +101,7 @@ final class CommandProcessor {
         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? NostrIdentityBridge.deriveIdentity(forGeohash: ch.geohash))?.publicKeyHex.lowercased()
+            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
@@ -148,8 +147,8 @@ final class CommandProcessor {
             // In private chat
             if let peerNickname = meshService?.peerNickname(peerID: targetPeerID) {
                 let personalMessage = "* \(emoji) \(myNickname) \(action) you\(suffix) *"
-                meshService?.sendPrivateMessage(personalMessage, to: targetPeerID, 
-                                               recipientNickname: peerNickname, 
+                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 = {
@@ -189,7 +188,7 @@ final class CommandProcessor {
             }
 
             // Geohash blocked names (prefer visible display names; fallback to #suffix)
-            let geoBlocked = Array(SecureIdentityStateManager.shared.getBlockedNostrPubkeys())
+            let geoBlocked = Array(identityManager.getBlockedNostrPubkeys())
             var geoNames: [String] = []
             if let vm = chatViewModel {
                 let visible = vm.visibleGeohashPeople()
@@ -213,14 +212,14 @@ final class CommandProcessor {
         
         if let peerID = chatViewModel?.getPeerIDForNickname(nickname),
            let fingerprint = meshService?.getFingerprint(for: peerID) {
-            if SecureIdentityStateManager.shared.isBlocked(fingerprint: fingerprint) {
+            if identityManager.isBlocked(fingerprint: fingerprint) {
                 return .success(message: "\(nickname) is already blocked")
             }
             // Block the user (mesh/noise identity)
-            if var identity = SecureIdentityStateManager.shared.getSocialIdentity(for: fingerprint) {
+            if var identity = identityManager.getSocialIdentity(for: fingerprint) {
                 identity.isBlocked = true
                 identity.isFavorite = false
-                SecureIdentityStateManager.shared.updateSocialIdentity(identity)
+                identityManager.updateSocialIdentity(identity)
             } else {
                 let blockedIdentity = SocialIdentity(
                     fingerprint: fingerprint,
@@ -231,16 +230,16 @@ final class CommandProcessor {
                     isBlocked: true,
                     notes: nil
                 )
-                SecureIdentityStateManager.shared.updateSocialIdentity(blockedIdentity)
+                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 SecureIdentityStateManager.shared.isNostrBlocked(pubkeyHexLowercased: pub) {
+            if identityManager.isNostrBlocked(pubkeyHexLowercased: pub) {
                 return .success(message: "\(nickname) is already blocked")
             }
-            SecureIdentityStateManager.shared.setNostrBlocked(pub, isBlocked: true)
+            identityManager.setNostrBlocked(pub, isBlocked: true)
             return .success(message: "blocked \(nickname) in geohash chats")
         }
         
@@ -257,18 +256,18 @@ final class CommandProcessor {
         
         if let peerID = chatViewModel?.getPeerIDForNickname(nickname),
            let fingerprint = meshService?.getFingerprint(for: peerID) {
-            if !SecureIdentityStateManager.shared.isBlocked(fingerprint: fingerprint) {
+            if !identityManager.isBlocked(fingerprint: fingerprint) {
                 return .success(message: "\(nickname) is not blocked")
             }
-            SecureIdentityStateManager.shared.setBlocked(fingerprint, isBlocked: false)
+            identityManager.setBlocked(fingerprint, isBlocked: false)
             return .success(message: "unblocked \(nickname)")
         }
         // Try geohash unblock
         if let pub = chatViewModel?.nostrPubkeyForDisplayName(nickname) {
-            if !SecureIdentityStateManager.shared.isNostrBlocked(pubkeyHexLowercased: pub) {
+            if !identityManager.isNostrBlocked(pubkeyHexLowercased: pub) {
                 return .success(message: "\(nickname) is not blocked")
             }
-            SecureIdentityStateManager.shared.setNostrBlocked(pub, isBlocked: false)
+            identityManager.setNostrBlocked(pub, isBlocked: false)
             return .success(message: "unblocked \(nickname) in geohash chats")
         }
         return .error(message: "cannot unblock \(nickname): not found")
@@ -283,7 +282,7 @@ final class CommandProcessor {
         let nickname = targetName.hasPrefix("@") ? String(targetName.dropFirst()) : targetName
         
         guard let peerID = chatViewModel?.getPeerIDForNickname(nickname),
-              let noisePublicKey = Data(hexString: peerID) else {
+              let noisePublicKey = Data(hexString: peerID.id) else {
             return .error(message: "can't find peer: \(nickname)")
         }
         
@@ -309,19 +308,4 @@ final class CommandProcessor {
         }
     }
     
-    private func handleHelp() -> CommandResult {
-        let helpText = """
-        commands:
-        /msg @name - start private chat
-        /who - list who's online
-        /clear - clear messages
-        /hug @name - send a hug
-        /slap @name - slap with a trout
-        /fav @name - add to favorites
-        /unfav @name - remove from favorites
-        /block @name - block
-        /unblock @name - unblock
-        """
-        return .success(message: helpText)
-    }
 }

bitchat/Services/FavoritesPersistenceService.swift

@@ -1,3 +1,4 @@
+import BitLogger
 import Foundation
 import Combine
 
@@ -13,14 +14,19 @@ final class FavoritesPersistenceService: ObservableObject {
         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> = []
@@ -30,7 +36,8 @@ final class FavoritesPersistenceService: ObservableObject {
     
     static let shared = FavoritesPersistenceService()
     
-    private init() {
+    init(keychain: KeychainHelperProtocol = KeychainHelper()) {
+        self.keychain = keychain
         loadFavorites()
         
         // Update mutual favorites when favorites change
@@ -174,125 +181,15 @@ final class FavoritesPersistenceService: ObservableObject {
 
     /// 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: String) -> FavoriteRelationship? {
+    func getFavoriteStatus(forPeerID peerID: PeerID) -> FavoriteRelationship? {
         // Quick sanity: peerID should be 16 hex chars (8 bytes)
-        guard peerID.count == 16 else { return nil }
-        for (pubkey, rel) in favorites {
-            let derived = PeerIDUtils.derivePeerID(fromPublicKey: pubkey)
-            if derived == peerID { return rel }
+        guard peerID.isShort else { return nil }
+        for (pubkey, rel) in favorites where PeerID(publicKey: pubkey) == peerID {
+            return rel
         }
         return nil
     }
     
-    /// Update Nostr public key for a peer
-    func updateNostrPublicKey(for peerNoisePublicKey: Data, nostrPubkey: String) {
-        guard let existing = favorites[peerNoisePublicKey] else { return }
-        
-        let updated = FavoriteRelationship(
-            peerNoisePublicKey: existing.peerNoisePublicKey,
-            peerNostrPublicKey: nostrPubkey,
-            peerNickname: existing.peerNickname,
-            isFavorite: existing.isFavorite,
-            theyFavoritedUs: existing.theyFavoritedUs,
-            favoritedAt: existing.favoritedAt,
-            lastUpdated: Date()
-        )
-        
-        favorites[peerNoisePublicKey] = updated
-        saveFavorites()
-    }
-    
-    /// Update nickname for an existing favorite
-    func updateNickname(for peerNoisePublicKey: Data, newNickname: String) {
-        guard let existing = favorites[peerNoisePublicKey] else { return }
-        
-        // Skip if nickname hasn't changed
-        if existing.peerNickname == newNickname { return }
-        
-        // Updating nickname for favorite
-        
-        let updated = FavoriteRelationship(
-            peerNoisePublicKey: existing.peerNoisePublicKey,
-            peerNostrPublicKey: existing.peerNostrPublicKey,
-            peerNickname: newNickname,
-            isFavorite: existing.isFavorite,
-            theyFavoritedUs: existing.theyFavoritedUs,
-            favoritedAt: existing.favoritedAt,
-            lastUpdated: Date()
-        )
-        
-        favorites[peerNoisePublicKey] = updated
-        saveFavorites()
-        
-        // Notify observers
-        NotificationCenter.default.post(
-            name: .favoriteStatusChanged,
-            object: nil,
-            userInfo: ["peerPublicKey": peerNoisePublicKey]
-        )
-    }
-    
-    /// Update noise public key when peer reconnects with new ID
-    func updateNoisePublicKey(from oldKey: Data, to newKey: Data, peerNickname: String) {
-        guard let existing = favorites[oldKey] else { 
-            SecureLogger.warning("⚠️ Cannot update noise key - no favorite found for \(oldKey.hexEncodedString())", category: .session)
-            return 
-        }
-        
-        // Check if we already have a favorite with the new key
-        if favorites[newKey] != nil {
-            SecureLogger.warning("⚠️ Favorite already exists with new key \(newKey.hexEncodedString()), removing old entry", category: .session)
-            favorites.removeValue(forKey: oldKey)
-            saveFavorites()
-            return
-        }
-        
-        // Updating noise public key
-        
-        // Remove old entry
-        favorites.removeValue(forKey: oldKey)
-        
-        // Add with new key
-        let updated = FavoriteRelationship(
-            peerNoisePublicKey: newKey,
-            peerNostrPublicKey: existing.peerNostrPublicKey,
-            peerNickname: peerNickname,
-            isFavorite: existing.isFavorite,
-            theyFavoritedUs: existing.theyFavoritedUs,
-            favoritedAt: existing.favoritedAt,
-            lastUpdated: Date()
-        )
-        
-        favorites[newKey] = updated
-        saveFavorites()
-        
-        // Notify observers with both old and new keys
-        NotificationCenter.default.post(
-            name: .favoriteStatusChanged,
-            object: nil,
-            userInfo: [
-                "peerPublicKey": newKey,
-                "oldPeerPublicKey": oldKey,
-                "isKeyUpdate": true
-            ]
-        )
-    }
-    
-    /// Get all favorites (including non-mutual)
-    func getAllFavorites() -> [FavoriteRelationship] {
-        favorites.values.filter { $0.isFavorite }
-    }
-    
-    /// Get only mutual favorites
-    func getMutualFavorites() -> [FavoriteRelationship] {
-        favorites.values.filter { $0.isMutual }
-    }
-    
-    /// Get all favorite relationships (including where they favorited us)
-    func getAllRelationships() -> [FavoriteRelationship] {
-        Array(favorites.values)
-    }
-    
     /// Clear all favorites - used for panic mode
     func clearAllFavorites() {
         SecureLogger.warning("🧹 Clearing all favorites (panic mode)", category: .session)
@@ -301,7 +198,7 @@ final class FavoritesPersistenceService: ObservableObject {
         saveFavorites()
         
         // Delete from keychain directly
-        KeychainHelper.delete(
+        keychain.delete(
             key: Self.storageKey,
             service: Self.keychainService
         )
@@ -321,10 +218,11 @@ final class FavoritesPersistenceService: ObservableObject {
             let data = try encoder.encode(relationships)
             
             // Store in keychain for security
-            KeychainHelper.save(
+            keychain.save(
                 key: Self.storageKey,
                 data: data,
-                service: Self.keychainService
+                service: Self.keychainService,
+                accessible: nil
             )
             
             // Successfully saved favorites
@@ -336,7 +234,7 @@ final class FavoritesPersistenceService: ObservableObject {
     private func loadFavorites() {
         // Loading favorites from keychain
         
-        guard let data = KeychainHelper.load(
+        guard let data = keychain.load(
             key: Self.storageKey,
             service: Self.keychainService
         ) else { 

bitchat/Services/GeohashBookmarksStore.swift

@@ -20,8 +20,11 @@ final class GeohashBookmarksStore: ObservableObject {
     private let geocoder = CLGeocoder()
     private var resolving: Set<String> = []
     #endif
+    
+    private let storage: UserDefaults
 
-    private init() {
+    init(storage: UserDefaults = .standard) {
+        self.storage = storage
         load()
     }
 
@@ -64,7 +67,7 @@ final class GeohashBookmarksStore: ObservableObject {
 
     // MARK: - Persistence
     private func load() {
-        guard let data = UserDefaults.standard.data(forKey: storeKey) else { return }
+        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>()
@@ -81,7 +84,7 @@ final class GeohashBookmarksStore: ObservableObject {
             membership = seen
         }
         // Load any saved names
-        if let namesData = UserDefaults.standard.data(forKey: namesStoreKey),
+        if let namesData = storage.data(forKey: namesStoreKey),
            let dict = try? JSONDecoder().decode([String: String].self, from: namesData) {
             bookmarkNames = dict
         }
@@ -89,13 +92,13 @@ final class GeohashBookmarksStore: ObservableObject {
 
     private func persist() {
         if let data = try? JSONEncoder().encode(bookmarks) {
-            UserDefaults.standard.set(data, forKey: storeKey)
+            storage.set(data, forKey: storeKey)
         }
     }
 
     private func persistNames() {
         if let data = try? JSONEncoder().encode(bookmarkNames) {
-            UserDefaults.standard.set(data, forKey: namesStoreKey)
+            storage.set(data, forKey: namesStoreKey)
         }
     }
 
@@ -213,15 +216,4 @@ final class GeohashBookmarksStore: ObservableObject {
         }
     }
     #endif
-
-    #if DEBUG
-    /// Testing-only reset helper
-    func _resetForTesting() {
-        bookmarks.removeAll()
-        membership.removeAll()
-        bookmarkNames.removeAll()
-        persist()
-        persistNames()
-    }
-    #endif
 }

bitchat/Services/KeychainManager.swift

@@ -6,46 +6,26 @@
 // For more information, see <https://unlicense.org>
 //
 
+import BitLogger
 import Foundation
 import Security
 
-final 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() {}
-    
-    
-    private func isSandboxed() -> Bool {
-        #if os(macOS)
-        // More robust sandbox detection using multiple methods
-        
-        // Method 1: Check environment variable (can be spoofed)
-        let environment = ProcessInfo.processInfo.environment
-        let hasEnvVar = environment["APP_SANDBOX_CONTAINER_ID"] != nil
-        
-        // Method 2: Check if we can access a path outside sandbox
-        let homeDir = FileManager.default.homeDirectoryForCurrentUser
-        let testPath = homeDir.appendingPathComponent("../../../tmp/bitchat_sandbox_test_\(UUID().uuidString)")
-        let canWriteOutsideSandbox = FileManager.default.createFile(atPath: testPath.path, contents: nil, attributes: nil)
-        if canWriteOutsideSandbox {
-            try? FileManager.default.removeItem(at: testPath)
-        }
-        
-        // Method 3: Check container path
-        let containerPath = FileManager.default.urls(for: .libraryDirectory, in: .userDomainMask).first?.path ?? ""
-        let hasContainerPath = containerPath.contains("/Containers/")
-        
-        // If any method indicates sandbox, we consider it sandboxed
-        return hasEnvVar || !canWriteOutsideSandbox || hasContainerPath
-        #else
-        // iOS is always sandboxed
-        return true
-        #endif
-    }
+    private let service = BitchatApp.bundleID
+    private let appGroup = "group.\(BitchatApp.bundleID)"
     
     // MARK: - Identity Keys
     
@@ -274,6 +254,7 @@ final class KeychainManager {
             "com.bitchat.deviceidentity", 
             "com.bitchat.noise.identity",
             "chat.bitchat.passwords",
+            "chat.bitchat.nostr",
             "bitchat.keychain",
             "bitchat",
             "com.bitchat"
@@ -310,7 +291,7 @@ final class KeychainManager {
     // MARK: - Security Utilities
     
     /// Securely clear sensitive data from memory
-    static func secureClear(_ data: inout Data) {
+    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)
@@ -319,7 +300,7 @@ final class KeychainManager {
     }
     
     /// Securely clear sensitive string from memory
-    static func secureClear(_ string: inout String) {
+    func secureClear(_ string: inout String) {
         // Convert to mutable data and clear
         if var data = string.data(using: .utf8) {
             secureClear(&data)

bitchat/Services/LocationChannelManager.swift

@@ -1,3 +1,4 @@
+import BitLogger
 import Foundation
 import Combine
 
@@ -63,7 +64,9 @@ final class LocationChannelManager: NSObject, CLLocationManagerDelegate, Observa
         switch status {
         case .authorizedAlways, .authorizedWhenInUse, .authorized:
             break // will compute from location
-        default:
+        case .notDetermined, .restricted, .denied:
+            fallthrough
+        @unknown default:
             if case .location(let ch) = selectedChannel {
                 teleported = teleportedSet.contains(ch.geohash)
             }
@@ -285,12 +288,18 @@ final class LocationChannelManager: NSObject, CLLocationManagerDelegate, Observa
         } else if let locality = pm.locality, !locality.isEmpty {
             dict[.neighborhood] = locality
         }
-        // Block: reuse neighborhood/locality granularity without exposing street level
+        // 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
     }
 }

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/MessageRouter.swift

@@ -1,3 +1,4 @@
+import BitLogger
 import Foundation
 
 /// Routes messages between BLE and Nostr transports
@@ -5,7 +6,7 @@ import Foundation
 final class MessageRouter {
     private let mesh: Transport
     private let nostr: NostrTransport
-    private var outbox: [String: [(content: String, nickname: String, messageID: String)]] = [:] // peerID -> queued messages
+    private var outbox: [PeerID: [(content: String, nickname: String, messageID: String)]] = [:] // peerID -> queued messages
 
     init(mesh: Transport, nostr: NostrTransport) {
         self.mesh = mesh
@@ -20,7 +21,7 @@ final class MessageRouter {
         ) { [weak self] note in
             guard let self = self else { return }
             if let data = note.userInfo?["peerPublicKey"] as? Data {
-                let peerID = PeerIDUtils.derivePeerID(fromPublicKey: data)
+                let peerID = PeerID(publicKey: data)
                 Task { @MainActor in
                     self.flushOutbox(for: peerID)
                 }
@@ -28,7 +29,7 @@ final class MessageRouter {
             // Handle key updates
             if let newKey = note.userInfo?["peerPublicKey"] as? Data,
                let _ = note.userInfo?["isKeyUpdate"] as? Bool {
-                let peerID = PeerIDUtils.derivePeerID(fromPublicKey: newKey)
+                let peerID = PeerID(publicKey: newKey)
                 Task { @MainActor in
                     self.flushOutbox(for: peerID)
                 }
@@ -36,44 +37,45 @@ final class MessageRouter {
         }
     }
 
-    func sendPrivate(_ content: String, to peerID: String, recipientNickname: String, messageID: String) {
+    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.prefix(8))… id=\(messageID.prefix(8))…", category: .session)
+            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.prefix(8))… id=\(messageID.prefix(8))…", category: .session)
+            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.prefix(8))… (no mesh, no Nostr mapping) id=\(messageID.prefix(8))…", category: .session)
+            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: String) {
+    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.prefix(8))… id=\(receipt.originalMessageID.prefix(8))…", category: .session)
+            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.prefix(8))… id=\(receipt.originalMessageID.prefix(8))…", category: .session)
+            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: String) {
+    func sendDeliveryAck(_ messageID: String, to peerID: PeerID) {
         if mesh.isPeerReachable(peerID) {
-            SecureLogger.debug("Routing DELIVERED ack via mesh (reachable) to \(peerID.prefix(8))… id=\(messageID.prefix(8))…", category: .session)
+            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: String, isFavorite: Bool) {
+    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 {
@@ -82,16 +84,16 @@ final class MessageRouter {
     }
 
     // MARK: - Outbox Management
-    private func canSendViaNostr(peerID: String) -> Bool {
+    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 peerID.count == 64, let noiseKey = Data(hexString: peerID) {
+        if let noiseKey = peerID.noiseKey {
             if let fav = FavoritesPersistenceService.shared.getFavoriteStatus(for: noiseKey),
                fav.peerNostrPublicKey != nil {
                 return true
             }
-        } else if peerID.count == 16 {
+        } else if peerID.isShort {
             if let fav = FavoritesPersistenceService.shared.getFavoriteStatus(forPeerID: peerID),
                fav.peerNostrPublicKey != nil {
                 return true
@@ -100,17 +102,17 @@ final class MessageRouter {
         return false
     }
 
-    func flushOutbox(for peerID: String) {
+    func flushOutbox(for peerID: PeerID) {
         guard let queued = outbox[peerID], !queued.isEmpty else { return }
-        SecureLogger.debug("Flushing outbox for \(peerID.prefix(8))… count=\(queued.count)", category: .session)
+        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.prefix(8))… id=\(messageID.prefix(8))…", category: .session)
+                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.prefix(8))… id=\(messageID.prefix(8))…", category: .session)
+                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

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

@@ -62,7 +62,6 @@
 /// ## Integration Points
 /// - **BLEService**: Calls this service for all private messages
 /// - **ChatViewModel**: Monitors encryption status for UI indicators
-/// - **NoiseHandshakeCoordinator**: Prevents handshake race conditions
 /// - **KeychainManager**: Secure storage for identity keys
 ///
 /// ## Thread Safety
@@ -83,6 +82,7 @@
 /// - Background queue for CPU-intensive operations
 ///
 
+import BitLogger
 import Foundation
 import CryptoKit
 
@@ -115,15 +115,30 @@ enum EncryptionStatus: Equatable {
     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")
         }
     }
 }
@@ -147,32 +162,33 @@ final 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
-    private var onPeerAuthenticatedHandlers: [((String, String) -> Void)] = [] // Array of handlers for peer authentication
-    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
     
     // Add a handler for peer authentication
-    func addOnPeerAuthenticatedHandler(_ handler: @escaping (String, String) -> Void) {
+    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: ((String, String) -> Void)? {
+    var onPeerAuthenticated: ((PeerID, String) -> Void)? {
         get { nil } // Always return nil for backward compatibility
         set {
             if let handler = newValue {
@@ -181,12 +197,14 @@ final class NoiseEncryptionService {
         }
     }
     
-    init() {
+    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)
@@ -197,7 +215,7 @@ final class NoiseEncryptionService {
             let keyData = loadedKey.rawRepresentation
             
             // Save to keychain
-            let saved = KeychainManager.shared.saveIdentityKey(keyData, forKey: "noiseStaticKey")
+            let saved = keychain.saveIdentityKey(keyData, forKey: "noiseStaticKey")
             SecureLogger.logKeyOperation(.create, keyType: "noiseStaticKey", success: saved)
         }
         
@@ -209,7 +227,7 @@ final 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)
@@ -220,7 +238,7 @@ final class NoiseEncryptionService {
             let keyData = loadedSigningKey.rawRepresentation
             
             // Save to keychain
-            let saved = KeychainManager.shared.saveIdentityKey(keyData, forKey: "ed25519SigningKey")
+            let saved = keychain.saveIdentityKey(keyData, forKey: "ed25519SigningKey")
             SecureLogger.logKeyOperation(.create, keyType: "ed25519SigningKey", success: saved)
         }
         
@@ -229,7 +247,7 @@ final 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
@@ -254,20 +272,19 @@ final 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")
+        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
@@ -387,11 +404,11 @@ final class NoiseEncryptionService {
     // 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.warning(.authenticationFailed(peerID: peerID))
+        guard peerID.isValid else {
+            SecureLogger.warning(.authenticationFailed(peerID: peerID.id))
             throw NoiseSecurityError.invalidPeerID
         }
         
@@ -401,7 +418,7 @@ final class NoiseEncryptionService {
             throw NoiseSecurityError.rateLimitExceeded
         }
         
-        SecureLogger.info(.handshakeStarted(peerID: peerID))
+        SecureLogger.info(.handshakeStarted(peerID: peerID.id))
         
         // Return raw handshake data without wrapper
         // The Noise protocol handles its own message format
@@ -410,17 +427,17 @@ final 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.warning(.authenticationFailed(peerID: peerID))
+        guard peerID.isValid else {
+            SecureLogger.warning(.authenticationFailed(peerID: peerID.id))
             throw NoiseSecurityError.invalidPeerID
         }
         
         // Validate message size
         guard NoiseSecurityValidator.validateHandshakeMessageSize(message) else {
-            SecureLogger.warning(.handshakeFailed(peerID: peerID, error: "Message too large"))
+            SecureLogger.warning(.handshakeFailed(peerID: peerID.id, error: "Message too large"))
             throw NoiseSecurityError.messageTooLarge
         }
         
@@ -440,19 +457,19 @@ final 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
@@ -474,7 +491,7 @@ final 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
@@ -496,38 +513,26 @@ final 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.info(.sessionExpired(peerID: peerID))
+        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) {
@@ -536,7 +541,7 @@ final class NoiseEncryptionService {
         }
         
         // Log security event
-        SecureLogger.info(.handshakeCompleted(peerID: peerID))
+        SecureLogger.info(.handshakeCompleted(peerID: peerID.id))
         
         // Notify all handlers about authentication
         serviceQueue.async { [weak self] in
@@ -545,11 +550,6 @@ final class NoiseEncryptionService {
             }
         }
     }
-    
-    private func calculateFingerprint(for publicKey: Curve25519.KeyAgreement.PublicKey) -> String {
-        let hash = SHA256.hash(data: publicKey.rawRepresentation)
-        return hash.map { String(format: "%02x", $0) }.joined()
-    }
         
     // MARK: - Session Maintenance
     

bitchat/Services/NostrTransport.swift

@@ -1,28 +1,39 @@
+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] { [] }
 
-    // Provide BLE short peer ID for BitChat embedding
-    var senderPeerID: String = ""
-
-    // Throttle READ receipts to avoid relay rate limits
-    private struct QueuedRead {
-        let receipt: ReadReceipt
-        let peerID: String
-    }
-    private var readQueue: [QueuedRead] = []
-    private var isSendingReadAcks = false
-    private let readAckInterval: TimeInterval = TransportConfig.nostrReadAckInterval
-
-    var myPeerID: String { senderPeerID }
+    var myPeerID: PeerID { senderPeerID }
     var myNickname: String { "" }
     func setNickname(_ nickname: String) { /* not used for Nostr */ }
 
@@ -30,28 +41,34 @@ final class NostrTransport: Transport {
     func stopServices() { /* no-op */ }
     func emergencyDisconnectAll() { /* no-op */ }
 
-    func isPeerConnected(_ peerID: String) -> Bool { false }
-    func isPeerReachable(_ peerID: String) -> Bool { false }
-    func peerNickname(peerID: String) -> String? { nil }
-    func getPeerNicknames() -> [String : String] { [:] }
+    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: String) -> String? { nil }
-    func getNoiseSessionState(for peerID: String) -> LazyHandshakeState { .none }
-    func triggerHandshake(with peerID: String) { /* no-op */ }
+    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 = {
-        NoiseEncryptionService()
-    }()
-    func getNoiseService() -> NoiseEncryptionService { Self.cachedNoiseService }
+    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: String, recipientNickname: String, messageID: String) {
+    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? NostrIdentityBridge.getCurrentNostrIdentity() else { return }
-            SecureLogger.debug("NostrTransport: preparing PM to \(recipientNpub.prefix(16))… for peerID \(peerID.prefix(8))… id=\(messageID.prefix(8))…", category: .session)
+            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 {
@@ -78,12 +95,113 @@ final class NostrTransport: Transport {
         }
     }
 
-    func sendReadReceipt(_ receipt: ReadReceipt, to peerID: String) {
+    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 }
@@ -96,7 +214,7 @@ final class NostrTransport: Transport {
         let item = readQueue.removeFirst()
         Task { @MainActor in
             guard let recipientNpub = resolveRecipientNpub(for: item.peerID) else { scheduleNextReadAck(); return }
-            guard let senderIdentity = try? NostrIdentityBridge.getCurrentNostrIdentity() 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
@@ -127,111 +245,18 @@ final class NostrTransport: Transport {
         }
     }
 
-    func sendFavoriteNotification(to peerID: String, isFavorite: Bool) {
-        Task { @MainActor in
-            guard let recipientNpub = resolveRecipientNpub(for: peerID) else { return }
-            guard let senderIdentity = try? NostrIdentityBridge.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)
-        }
-    }
-
-    // MARK: - Helpers
     @MainActor
-    private func resolveRecipientNpub(for peerID: String) -> String? {
-        if let noiseKey = Data(hexString: peerID),
+    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.count == 16,
+        if peerID.id.count == 16,
            let fav = FavoritesPersistenceService.shared.getFavoriteStatus(forPeerID: peerID),
            let npub = fav.peerNostrPublicKey {
             return npub
         }
         return nil
     }
-
-    func sendBroadcastAnnounce() { /* no-op for Nostr */ }
-    func sendDeliveryAck(for messageID: String, to peerID: String) {
-        Task { @MainActor in
-            guard let recipientNpub = resolveRecipientNpub(for: peerID) else { return }
-            guard let senderIdentity = try? NostrIdentityBridge.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 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)
-        }
-    }
 }

bitchat/Services/NotificationService.swift

@@ -29,28 +29,30 @@ final 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) {
@@ -61,35 +63,15 @@ final class NotificationService {
         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)"
@@ -103,25 +85,12 @@ final class NotificationService {
         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)
+    }
+}

bitchat/Services/PrivateChatManager.swift

@@ -6,14 +6,15 @@
 // This is free and unencumbered software released into the public domain.
 //
 
+import BitLogger
 import Foundation
 import SwiftUI
 
 /// Manages all private chat functionality
 final class PrivateChatManager: ObservableObject {
-    @Published var privateChats: [String: [BitchatMessage]] = [:]
-    @Published var selectedPeer: String? = nil
-    @Published var unreadMessages: Set<String> = []
+    @Published var privateChats: [PeerID: [BitchatMessage]] = [:]
+    @Published var selectedPeer: PeerID? = nil
+    @Published var unreadMessages: Set<PeerID> = []
     
     private var selectedPeerFingerprint: String? = nil
     var sentReadReceipts: Set<String> = []  // Made accessible for ChatViewModel
@@ -30,7 +31,7 @@ final class PrivateChatManager: ObservableObject {
     private let privateChatCap = TransportConfig.privateChatCap
     
     /// Start a private chat with a peer
-    func startChat(with peerID: String) {
+    func startChat(with peerID: PeerID) {
         selectedPeer = peerID
         
         // Store fingerprint for persistence across reconnections
@@ -52,109 +53,33 @@ final class PrivateChatManager: ObservableObject {
         selectedPeer = nil
         selectedPeerFingerprint = nil
     }
-    
-    /// Send a private message
-    func sendMessage(_ content: String, to peerID: String) {
-        guard let meshService = meshService,
-              let peerNickname = meshService.peerNickname(peerID: peerID) else {
-            return
-        }
-        
-        let messageID = UUID().uuidString
-        
-        // Create local message
-        let message = BitchatMessage(
-            id: messageID,
-            sender: meshService.myNickname,
-            content: content,
-            timestamp: Date(),
-            isRelay: false,
-            originalSender: nil,
-            isPrivate: true,
-            recipientNickname: peerNickname,
-            senderPeerID: meshService.myPeerID,
-            mentions: nil,
-            deliveryStatus: .sending
-        )
-        
-        // Add to chat
-        if privateChats[peerID] == nil { privateChats[peerID] = [] }
-        privateChats[peerID]?.append(message)
-        // Enforce per-chat cap on local append
-        if var arr = privateChats[peerID], arr.count > privateChatCap {
-            let remove = arr.count - privateChatCap
-            arr.removeFirst(remove)
-            privateChats[peerID] = arr
-        }
-        
-        // Send via mesh service
-        meshService.sendPrivateMessage(content, to: peerID, recipientNickname: peerNickname, messageID: messageID)
-    }
-    
-    /// Handle incoming private message
-    func handleIncomingMessage(_ message: BitchatMessage) {
-        guard let senderPeerID = message.senderPeerID else { return }
-        
-        // Initialize chat if needed
-        if privateChats[senderPeerID] == nil {
-            privateChats[senderPeerID] = []
-        }
-        
-        // Deduplicate by ID: replace existing message if present, else append
-        if let idx = privateChats[senderPeerID]?.firstIndex(where: { $0.id == message.id }) {
-            privateChats[senderPeerID]?[idx] = message
-        } else {
-            privateChats[senderPeerID]?.append(message)
-        }
-
-        // Sanitize chat to avoid duplicate IDs and sort by timestamp
-        sanitizeChat(for: senderPeerID)
-        // Enforce cap after sanitize
-        if var arr = privateChats[senderPeerID], arr.count > privateChatCap {
-            let remove = arr.count - privateChatCap
-            arr.removeFirst(remove)
-            privateChats[senderPeerID] = arr
-        }
-        
-        // Mark as unread if not in this chat
-        if selectedPeer != senderPeerID {
-            unreadMessages.insert(senderPeerID)
-            
-            // Avoid notifying for messages already marked as read (dup/resubscribe cases)
-            if !sentReadReceipts.contains(message.id) {
-                NotificationService.shared.sendPrivateMessageNotification(
-                    from: message.sender,
-                    message: message.content,
-                    peerID: senderPeerID
-                )
-            }
-        } else {
-            // Send read receipt if viewing this chat
-            sendReadReceipt(for: message)
-        }
-    }
 
     /// Remove duplicate messages by ID and keep chronological order
-    func sanitizeChat(for peerID: String) {
+    func sanitizeChat(for peerID: PeerID) {
         guard let arr = privateChats[peerID] else { return }
-        var seen = Set<String>()
+        if arr.count <= 1 {
+            return
+        }
+
+        var indexByID: [String: Int] = [:]
+        indexByID.reserveCapacity(arr.count)
         var deduped: [BitchatMessage] = []
+        deduped.reserveCapacity(arr.count)
+
         for msg in arr.sorted(by: { $0.timestamp < $1.timestamp }) {
-            if !seen.contains(msg.id) {
-                seen.insert(msg.id)
-                deduped.append(msg)
+            if let existing = indexByID[msg.id] {
+                deduped[existing] = msg
             } else {
-                // Replace previous with the latest occurrence (which is later in sort)
-                if let index = deduped.firstIndex(where: { $0.id == msg.id }) {
-                    deduped[index] = msg
-                }
+                indexByID[msg.id] = deduped.count
+                deduped.append(msg)
             }
         }
+
         privateChats[peerID] = deduped
     }
     
     /// Mark messages from a peer as read
-    func markAsRead(from peerID: String) {
+    func markAsRead(from peerID: PeerID) {
         unreadMessages.remove(peerID)
         
         // Send read receipts for unread messages that haven't been sent yet
@@ -167,48 +92,6 @@ final class PrivateChatManager: ObservableObject {
         }
     }
     
-    /// Update the selected peer if fingerprint matches (for reconnections)
-    func updateSelectedPeer(peers: [String: String]) {
-        guard let fingerprint = selectedPeerFingerprint else { return }
-        
-        // Find peer with matching fingerprint
-        for (peerID, _) in peers {
-            if meshService?.getFingerprint(for: peerID) == fingerprint {
-                selectedPeer = peerID
-                break
-            }
-        }
-    }
-    
-    /// Get chat messages for current context
-    func getCurrentMessages() -> [BitchatMessage] {
-        guard let peer = selectedPeer else { return [] }
-        return privateChats[peer] ?? []
-    }
-    
-    /// Clear a private chat
-    func clearChat(with peerID: String) {
-        privateChats[peerID]?.removeAll()
-    }
-    
-    /// Handle delivery acknowledgment
-    func handleDeliveryAck(messageID: String, from peerID: String) {
-        guard privateChats[peerID] != nil else { return }
-        
-        if let index = privateChats[peerID]?.firstIndex(where: { $0.id == messageID }) {
-            privateChats[peerID]?[index].deliveryStatus = .delivered(to: "recipient", at: Date())
-        }
-    }
-    
-    /// Handle read receipt
-    func handleReadReceipt(messageID: String, from peerID: String) {
-        guard privateChats[peerID] != nil else { return }
-        
-        if let index = privateChats[peerID]?.firstIndex(where: { $0.id == messageID }) {
-            privateChats[peerID]?[index].deliveryStatus = .read(by: "recipient", at: Date())
-        }
-    }
-    
     // MARK: - Private Methods
     
     private func sendReadReceipt(for message: BitchatMessage) {
@@ -222,13 +105,13 @@ final class PrivateChatManager: ObservableObject {
         // Create read receipt using the simplified method
         let receipt = ReadReceipt(
             originalMessageID: message.id,
-            readerID: meshService?.myPeerID ?? "",
+            readerID: meshService?.myPeerID ?? PeerID(str: ""),
             readerNickname: meshService?.myNickname ?? ""
         )
         
         // Route via MessageRouter to avoid handshakeRequired spam when session isn't established
         if let router = messageRouter {
-            SecureLogger.debug("PrivateChatManager: sending READ ack for \(message.id.prefix(8))… to \(senderPeerID.prefix(8))… via router", category: .session)
+            SecureLogger.debug("PrivateChatManager: sending READ ack for \(message.id.prefix(8))… to \(senderPeerID.id.prefix(8))… via router", category: .session)
             Task { @MainActor in
                 router.sendReadReceipt(receipt, to: senderPeerID)
             }

bitchat/Services/RelayController.swift

@@ -13,18 +13,23 @@ struct RelayController {
                        senderIsSelf: Bool,
                        isEncrypted: Bool,
                        isDirectedEncrypted: Bool,
+                       isFragment: Bool,
                        isDirectedFragment: Bool,
                        isHandshake: Bool,
                        isAnnounce: Bool,
                        degree: Int,
                        highDegreeThreshold: Int) -> RelayDecision {
+        let ttlCap = min(ttl, TransportConfig.messageTTLDefault)
+
         // Suppress obvious non-relays
-        if ttl <= 1 || senderIsSelf { return RelayDecision(shouldRelay: false, newTTL: ttl, delayMs: 0) }
+        if ttlCap <= 1 || senderIsSelf {
+            return RelayDecision(shouldRelay: false, newTTL: ttlCap, delayMs: 0)
+        }
 
         // For session-critical or directed traffic, be deterministic and reliable
         if isHandshake || isDirectedFragment || isDirectedEncrypted {
             // Always relay with no TTL cap for these types
-            let newTTL = (ttl &- 1)
+            let newTTL = ttlCap &- 1
             // Slight jitter to desynchronize without adding too much latency
             // Tighter for faster multi-hop handshakes and directed DMs
             let delayRange: ClosedRange<Int> = isHandshake ? 10...35 : 20...60
@@ -32,28 +37,27 @@ struct RelayController {
             return RelayDecision(shouldRelay: true, newTTL: newTTL, delayMs: delayMs)
         }
 
-        // Degree-aware probability to reduce floods in dense graphs (broadcast/public)
-        let baseProb: Double
-        switch degree {
-        case 0...2: baseProb = 1.0
-        case 3...4: baseProb = 0.9
-        case 5...6: baseProb = 0.7
-        case 7...9: baseProb = 0.55
-        default:    baseProb = 0.45
+        if isFragment {
+            let ttlLimit = min(ttlCap, TransportConfig.bleFragmentRelayTtlCap)
+            guard ttlLimit > 1 else {
+                return RelayDecision(shouldRelay: false, newTTL: ttlLimit, delayMs: 0)
+            }
+            let newTTL = ttlLimit &- 1
+            let delayMs = Int.random(in: TransportConfig.bleFragmentRelayMinDelayMs...TransportConfig.bleFragmentRelayMaxDelayMs)
+            return RelayDecision(shouldRelay: true, newTTL: newTTL, delayMs: delayMs)
         }
-        let prob = baseProb
-        let shouldRelay = Double.random(in: 0...1) <= prob
 
         // TTL clamping for broadcast
-        // - Dense graphs: keep very low to avoid floods
-        // - Sparse graphs: allow slightly longer reach for multi-hop discovery
-        // - Announces in sparse graphs get a bit more headroom
-        let ttlCap: UInt8 = {
-            if degree >= highDegreeThreshold { return 3 }
-            return isAnnounce ? 7 : 6
+        // - Dense graphs: keep lower but still allow multi-hop bridging
+        // - Announces get a bit more headroom
+        let ttlLimit: UInt8 = {
+            if degree >= highDegreeThreshold {
+                return max(UInt8(2), min(ttlCap, UInt8(5)))
+            }
+            let preferred = UInt8(isAnnounce ? 7 : 6)
+            return max(UInt8(2), min(ttlCap, preferred))
         }()
-        let clamped = max(1, min(ttl, ttlCap))
-        let newTTL = clamped &- 1
+        let newTTL = ttlLimit &- 1
 
         // Wider jitter window to allow duplicate suppression to win more often
         // For sparse graphs (<=2), relay quickly to avoid cancellation races
@@ -64,6 +68,6 @@ struct RelayController {
         case 6...9: delayMs = Int.random(in: 80...180)
         default:    delayMs = Int.random(in: 100...220)
         }
-        return RelayDecision(shouldRelay: shouldRelay, newTTL: newTTL, delayMs: delayMs)
+        return RelayDecision(shouldRelay: true, newTTL: newTTL, delayMs: delayMs)
     }
 }

bitchat/Services/Tor/TorNotifications.swift

@@ -1,6 +0,0 @@
-import Foundation
-
-extension Notification.Name {
-    static let TorDidBecomeReady = Notification.Name("TorDidBecomeReady")
-    static let TorWillRestart = Notification.Name("TorWillRestart")
-}

bitchat/Services/TransferProgressManager.swift

@@ -0,0 +1,65 @@
+import Foundation
+import Combine
+
+/// Centralized progress bus for Bluetooth file transfers.
+/// Emits Combine events consumed by ChatViewModel to update UI progress indicators.
+final class TransferProgressManager {
+    static let shared = TransferProgressManager()
+
+    enum Event {
+        case started(id: String, totalFragments: Int)
+        case updated(id: String, sentFragments: Int, totalFragments: Int)
+        case completed(id: String, totalFragments: Int)
+        case cancelled(id: String, sentFragments: Int, totalFragments: Int)
+    }
+
+    private let subject = PassthroughSubject<Event, Never>()
+    private let queue = DispatchQueue(label: "com.bitchat.transfer-progress", attributes: .concurrent)
+    private var states: [String: (sent: Int, total: Int)] = [:]
+
+    var publisher: AnyPublisher<Event, Never> {
+        subject.eraseToAnyPublisher()
+    }
+
+    func start(id: String, totalFragments: Int) {
+        queue.async(flags: .barrier) { [weak self] in
+            guard let self = self else { return }
+            self.states[id] = (sent: 0, total: totalFragments)
+            self.subject.send(.started(id: id, totalFragments: totalFragments))
+        }
+    }
+
+    func recordFragmentSent(id: String) {
+        queue.async(flags: .barrier) { [weak self] in
+            guard let self = self, var state = self.states[id] else { return }
+            state.sent = min(state.sent + 1, state.total)
+            self.states[id] = state
+            self.subject.send(.updated(id: id, sentFragments: state.sent, totalFragments: state.total))
+            if state.sent >= state.total {
+                self.states.removeValue(forKey: id)
+                self.subject.send(.completed(id: id, totalFragments: state.total))
+            }
+        }
+    }
+
+    func cancel(id: String) {
+        queue.async(flags: .barrier) { [weak self] in
+            guard let self = self, let state = self.states.removeValue(forKey: id) else { return }
+            self.subject.send(.cancelled(id: id, sentFragments: state.sent, totalFragments: state.total))
+        }
+    }
+
+    func reset(id: String) {
+        queue.async(flags: .barrier) { [weak self] in
+            self?.states.removeValue(forKey: id)
+        }
+    }
+
+    func snapshot(id: String) -> (sent: Int, total: Int)? {
+        var result: (sent: Int, total: Int)?
+        queue.sync {
+            result = states[id]
+        }
+        return result
+    }
+}

bitchat/Services/Transport.swift

@@ -4,7 +4,7 @@ import Combine
 /// Abstract transport interface used by ChatViewModel and services.
 /// BLEService implements this protocol; a future Nostr transport can too.
 struct TransportPeerSnapshot: Equatable, Hashable {
-    let id: String
+    let peerID: PeerID
     let nickname: String
     let isConnected: Bool
     let noisePublicKey: Data?
@@ -12,13 +12,17 @@ struct TransportPeerSnapshot: Equatable, Hashable {
 }
 
 protocol Transport: AnyObject {
-    // Peer events (preferred over publishers for UI)
-    var peerEventsDelegate: TransportPeerEventsDelegate? { get set }
     // Event sink
     var delegate: BitchatDelegate? { get set }
+    // Peer events (preferred over publishers for UI)
+    var peerEventsDelegate: TransportPeerEventsDelegate? { get set }
+    
+    // Peer snapshots (for non-UI services)
+    var peerSnapshotPublisher: AnyPublisher<[TransportPeerSnapshot], Never> { get }
+    func currentPeerSnapshots() -> [TransportPeerSnapshot]
 
     // Identity
-    var myPeerID: String { get }
+    var myPeerID: PeerID { get }
     var myNickname: String { get }
     func setNickname(_ nickname: String)
 
@@ -28,37 +32,44 @@ protocol Transport: AnyObject {
     func emergencyDisconnectAll()
 
     // Connectivity and peers
-    func isPeerConnected(_ peerID: String) -> Bool
-    func isPeerReachable(_ peerID: String) -> Bool
-    func peerNickname(peerID: String) -> String?
-    func getPeerNicknames() -> [String: String]
+    func isPeerConnected(_ peerID: PeerID) -> Bool
+    func isPeerReachable(_ peerID: PeerID) -> Bool
+    func peerNickname(peerID: PeerID) -> String?
+    func getPeerNicknames() -> [PeerID: String]
 
     // Protocol utilities
-    func getFingerprint(for peerID: String) -> String?
-    func getNoiseSessionState(for peerID: String) -> LazyHandshakeState
-    func triggerHandshake(with peerID: String)
+    func getFingerprint(for peerID: PeerID) -> String?
+    func getNoiseSessionState(for peerID: PeerID) -> LazyHandshakeState
+    func triggerHandshake(with peerID: PeerID)
     func getNoiseService() -> NoiseEncryptionService
 
     // Messaging
     func sendMessage(_ content: String, mentions: [String])
-    func sendPrivateMessage(_ content: String, to peerID: String, recipientNickname: String, messageID: String)
-    func sendReadReceipt(_ receipt: ReadReceipt, to peerID: String)
-    func sendFavoriteNotification(to peerID: String, isFavorite: Bool)
+    func sendMessage(_ content: String, mentions: [String], messageID: String, timestamp: Date)
+    func sendPrivateMessage(_ content: String, to peerID: PeerID, recipientNickname: String, messageID: String)
+    func sendReadReceipt(_ receipt: ReadReceipt, to peerID: PeerID)
+    func sendFavoriteNotification(to peerID: PeerID, isFavorite: Bool)
     func sendBroadcastAnnounce()
-    func sendDeliveryAck(for messageID: String, to peerID: String)
+    func sendDeliveryAck(for messageID: String, to peerID: PeerID)
+    func sendFileBroadcast(_ packet: BitchatFilePacket, transferId: String)
+    func sendFilePrivate(_ packet: BitchatFilePacket, to peerID: PeerID, transferId: String)
+    func cancelTransfer(_ transferId: String)
 
     // QR verification (optional for transports)
-    func sendVerifyChallenge(to peerID: String, noiseKeyHex: String, nonceA: Data)
-    func sendVerifyResponse(to peerID: String, noiseKeyHex: String, nonceA: Data)
-
-    // Peer snapshots (for non-UI services)
-    var peerSnapshotPublisher: AnyPublisher<[TransportPeerSnapshot], Never> { get }
-    func currentPeerSnapshots() -> [TransportPeerSnapshot]
+    func sendVerifyChallenge(to peerID: PeerID, noiseKeyHex: String, nonceA: Data)
+    func sendVerifyResponse(to peerID: PeerID, noiseKeyHex: String, nonceA: Data)
 }
 
 extension Transport {
-    func sendVerifyChallenge(to peerID: String, noiseKeyHex: String, nonceA: Data) {}
-    func sendVerifyResponse(to peerID: String, noiseKeyHex: String, nonceA: Data) {}
+    func sendVerifyChallenge(to peerID: PeerID, noiseKeyHex: String, nonceA: Data) {}
+    func sendVerifyResponse(to peerID: PeerID, noiseKeyHex: String, nonceA: Data) {}
+    func sendFileBroadcast(_ packet: BitchatFilePacket, transferId: String) {}
+    func sendFilePrivate(_ packet: BitchatFilePacket, to peerID: PeerID, transferId: String) {}
+    func cancelTransfer(_ transferId: String) {}
+
+    func sendMessage(_ content: String, mentions: [String], messageID: String, timestamp: Date) {
+        sendMessage(content, mentions: mentions)
+    }
 }
 
 protocol TransportPeerEventsDelegate: AnyObject {

bitchat/Services/TransportConfig.swift

@@ -8,6 +8,10 @@ enum TransportConfig {
     static let messageTTLDefault: UInt8 = 7                 // Default TTL for mesh flooding
     static let bleMaxInFlightAssemblies: Int = 128          // Cap concurrent fragment assemblies
     static let bleHighDegreeThreshold: Int = 6              // For adaptive TTL/probabilistic relays
+    static let bleMaxConcurrentTransfers: Int = 2           // Limit simultaneous large media sends
+    static let bleFragmentRelayMinDelayMs: Int = 8          // Faster forwarding for media fragments
+    static let bleFragmentRelayMaxDelayMs: Int = 25         // Upper jitter bound for fragment relays
+    static let bleFragmentRelayTtlCap: UInt8 = 5            // Clamp fragment TTL to contain floods
 
     // UI / Storage Caps
     static let privateChatCap: Int = 1337
@@ -30,7 +34,11 @@ enum TransportConfig {
     static let bleDynamicRSSIThresholdDefault: Int = -90
     static let bleConnectionCandidatesMax: Int = 100
     static let blePendingWriteBufferCapBytes: Int = 1_000_000
-    static let blePendingNotificationsCapCount: Int = 20
+    static let bleNotificationAssemblerHardCapBytes: Int = 8 * 1024 * 1024
+    static let bleAssemblerStallResetMs: Int = 250
+    static let blePendingNotificationsCapCount: Int = 128
+    static let bleNotificationRetryDelayMs: Int = 25
+    static let bleNotificationRetryMaxAttempts: Int = 80
 
     // Nostr
     static let nostrReadAckInterval: TimeInterval = 0.35 // ~3 per second
@@ -62,6 +70,7 @@ enum TransportConfig {
     static let uiAnimationMediumSeconds: TimeInterval = 0.2
     static let uiAnimationSidebarSeconds: TimeInterval = 0.25
     static let uiRecentCutoffFiveMinutesSeconds: TimeInterval = 5 * 60
+    static let uiMeshEmptyConfirmationSeconds: TimeInterval = 30.0
 
     // BLE maintenance & thresholds
     static let bleMaintenanceInterval: TimeInterval = 5.0
@@ -103,7 +112,7 @@ enum TransportConfig {
     // Location
     static let locationDistanceFilterMeters: Double = 1000
     // Live (channel sheet open) distance threshold for meaningful updates
-    static let locationDistanceFilterLiveMeters: Double = 21.0
+    static let locationDistanceFilterLiveMeters: Double = 10.0
     static let locationLiveRefreshInterval: TimeInterval = 5.0
 
     // Notifications (geohash)
@@ -141,6 +150,9 @@ enum TransportConfig {
 
     // Geo relay directory
     static let geoRelayFetchIntervalSeconds: TimeInterval = 60 * 60 * 24
+    static let geoRelayRefreshCheckIntervalSeconds: TimeInterval = 60 * 60
+    static let geoRelayRetryInitialSeconds: TimeInterval = 60
+    static let geoRelayRetryMaxSeconds: TimeInterval = 60 * 60
 
     // BLE operational delays
     static let bleInitialAnnounceDelaySeconds: TimeInterval = 0.6
@@ -188,7 +200,7 @@ enum TransportConfig {
     static let uiWindowStepCount: Int = 200
 
     // Share extension
-    static let uiShareExtensionDismissDelaySeconds: TimeInterval = 0.3
+    static let uiShareExtensionDismissDelaySeconds: TimeInterval = 2.0
     static let uiShareAcceptWindowSeconds: TimeInterval = 30.0
     static let uiMigrationCutoffSeconds: TimeInterval = 24 * 60 * 60
 }

bitchat/Services/UnifiedPeerService.swift

@@ -6,10 +6,10 @@
 //  This is free and unencumbered software released into the public domain.
 //
 
+import BitLogger
 import Foundation
 import Combine
 import SwiftUI
-import CryptoKit
 
 /// Single source of truth for peer state, combining mesh connectivity and favorites
 @MainActor
@@ -18,23 +18,31 @@ final class UnifiedPeerService: ObservableObject, TransportPeerEventsDelegate {
     // MARK: - Published Properties
     
     @Published private(set) var peers: [BitchatPeer] = []
-    @Published private(set) var connectedPeerIDs: Set<String> = []
+    @Published private(set) var connectedPeerIDs: Set<PeerID> = []
     @Published private(set) var favorites: [BitchatPeer] = []
     @Published private(set) var mutualFavorites: [BitchatPeer] = []
     
     // MARK: - Private Properties
     
-    private var peerIndex: [String: BitchatPeer] = [:]
-    private var fingerprintCache: [String: String] = [:]  // peerID -> fingerprint
+    private var peerIndex: [PeerID: BitchatPeer] = [:]
+    private var fingerprintCache: [PeerID: String] = [:]
     private let meshService: Transport
+    private let idBridge: NostrIdentityBridge
+    private let identityManager: SecureIdentityStateManagerProtocol
     weak var messageRouter: MessageRouter?
     private let favoritesService = FavoritesPersistenceService.shared
     private var cancellables = Set<AnyCancellable>()
     
     // MARK: - Initialization
     
-    init(meshService: Transport) {
+    init(
+        meshService: Transport,
+        idBridge: NostrIdentityBridge,
+        identityManager: SecureIdentityStateManagerProtocol
+    ) {
         self.meshService = meshService
+        self.idBridge = idBridge
+        self.identityManager = identityManager
         
         // Subscribe to changes from both services
         setupSubscriptions()
@@ -75,12 +83,12 @@ final class UnifiedPeerService: ObservableObject, TransportPeerEventsDelegate {
         let favorites = favoritesService.favorites
         
         var enrichedPeers: [BitchatPeer] = []
-        var connected: Set<String> = []
-        var addedPeerIDs: Set<String> = []
+        var connected: Set<PeerID> = []
+        var addedPeerIDs: Set<PeerID> = []
         
         // Phase 1: Add all mesh peers (connected and reachable)
         for peerInfo in meshPeers {
-            let peerID = peerInfo.id
+            let peerID = peerInfo.peerID
             guard peerID != meshService.myPeerID else { continue }  // Never add self
             
             let peer = buildPeerFromMesh(
@@ -101,7 +109,7 @@ final class UnifiedPeerService: ObservableObject, TransportPeerEventsDelegate {
         
         // Phase 2: Add offline favorites that we actively favorite
         for (favoriteKey, favorite) in favorites where favorite.isFavorite {
-            let peerID = favoriteKey.hexEncodedString()
+            let peerID = PeerID(hexData: favoriteKey)
             
             // Skip if already added (connected peer)
             if addedPeerIDs.contains(peerID) { continue }
@@ -135,10 +143,10 @@ final class UnifiedPeerService: ObservableObject, TransportPeerEventsDelegate {
         // Phase 4: Build subsets and indices
         var favoritesList: [BitchatPeer] = []
         var mutualsList: [BitchatPeer] = []
-        var newIndex: [String: BitchatPeer] = [:]
+        var newIndex: [PeerID: BitchatPeer] = [:]
         
         for peer in enrichedPeers {
-            newIndex[peer.id] = peer
+            newIndex[peer.peerID] = peer
             
             if peer.isFavorite {
                 favoritesList.append(peer)
@@ -174,7 +182,7 @@ final class UnifiedPeerService: ObservableObject, TransportPeerEventsDelegate {
         // Determine reachability based on lastSeen and identity trust
         let now = Date()
         let fingerprint = peerInfo.noisePublicKey?.sha256Fingerprint()
-        let isVerified = fingerprint.map { SecureIdentityStateManager.shared.isVerified(fingerprint: $0) } ?? false
+        let isVerified = fingerprint.map { identityManager.isVerified(fingerprint: $0) } ?? false
         let isFav = peerInfo.noisePublicKey.flatMap { favorites[$0]?.isFavorite } ?? false
         let retention: TimeInterval = (isVerified || isFav) ? TransportConfig.bleReachabilityRetentionVerifiedSeconds : TransportConfig.bleReachabilityRetentionUnverifiedSeconds
         // A peer is reachable if we recently saw them AND we are attached to the mesh
@@ -182,7 +190,7 @@ final class UnifiedPeerService: ObservableObject, TransportPeerEventsDelegate {
         let isReachable = peerInfo.isConnected ? true : (withinRetention && meshAttached)
 
         var peer = BitchatPeer(
-            id: peerInfo.id,
+            peerID: peerInfo.peerID,
             noisePublicKey: peerInfo.noisePublicKey ?? Data(),
             nickname: peerInfo.nickname,
             lastSeen: peerInfo.lastSeen,
@@ -195,27 +203,6 @@ final class UnifiedPeerService: ObservableObject, TransportPeerEventsDelegate {
            let favoriteStatus = favorites[noiseKey] {
             peer.favoriteStatus = favoriteStatus
             peer.nostrPublicKey = favoriteStatus.peerNostrPublicKey
-        } else {
-            // Check by nickname for reconnected peers
-            let favoriteByNickname = favorites.values.first { 
-                $0.peerNickname == peerInfo.nickname 
-            }
-            
-            if let favorite = favoriteByNickname,
-               let noiseKey = peerInfo.noisePublicKey {
-                SecureLogger.debug("🔄 Found favorite for '\(peerInfo.nickname)' by nickname, updating noise key", category: .session)
-                
-                // Update the favorite's key in persistence
-                favoritesService.updateNoisePublicKey(
-                    from: favorite.peerNoisePublicKey,
-                    to: noiseKey,
-                    peerNickname: peerInfo.nickname
-                )
-                
-                // Get updated favorite
-                peer.favoriteStatus = favoritesService.getFavoriteStatus(for: noiseKey)
-                peer.nostrPublicKey = peer.favoriteStatus?.peerNostrPublicKey ?? favorite.peerNostrPublicKey
-            }
         }
         
         return peer
@@ -223,10 +210,10 @@ final class UnifiedPeerService: ObservableObject, TransportPeerEventsDelegate {
     
     private func buildPeerFromFavorite(
         favorite: FavoritesPersistenceService.FavoriteRelationship,
-        peerID: String
+        peerID: PeerID
     ) -> BitchatPeer {
         var peer = BitchatPeer(
-            id: peerID,
+            peerID: peerID,
             noisePublicKey: favorite.peerNoisePublicKey,
             nickname: favorite.peerNickname,
             lastSeen: favorite.lastUpdated,
@@ -243,32 +230,27 @@ final class UnifiedPeerService: ObservableObject, TransportPeerEventsDelegate {
     // MARK: - Public Methods
     
     /// Get peer by ID
-    func getPeer(by id: String) -> BitchatPeer? {
-        return peerIndex[id]
+    func getPeer(by peerID: PeerID) -> BitchatPeer? {
+        return peerIndex[peerID]
     }
     
     /// Get peer ID for nickname
-    func getPeerID(for nickname: String) -> String? {
+    func getPeerID(for nickname: String) -> PeerID? {
         for peer in peers {
             if peer.displayName == nickname || peer.nickname == nickname {
-                return peer.id
+                return peer.peerID
             }
         }
         return nil
     }
     
-    /// Check if peer is online
-    func isOnline(_ peerID: String) -> Bool {
-        return connectedPeerIDs.contains(peerID)
-    }
-    
     /// Check if peer is blocked
-    func isBlocked(_ peerID: String) -> Bool {
+    func isBlocked(_ peerID: PeerID) -> Bool {
         // Get fingerprint
         guard let fingerprint = getFingerprint(for: peerID) else { return false }
         
         // Check SecureIdentityStateManager for block status
-        if let identity = SecureIdentityStateManager.shared.getSocialIdentity(for: fingerprint) {
+        if let identity = identityManager.getSocialIdentity(for: fingerprint) {
             return identity.isBlocked
         }
         
@@ -276,8 +258,8 @@ final class UnifiedPeerService: ObservableObject, TransportPeerEventsDelegate {
     }
     
     /// Toggle favorite status
-    func toggleFavorite(_ peerID: String) {
-        guard let peer = getPeer(by: peerID) else { 
+    func toggleFavorite(_ peerID: PeerID) {
+        guard let peer = getPeer(by: peerID) else {
             SecureLogger.warning("⚠️ Cannot toggle favorite - peer not found: \(peerID)", category: .session)
             return 
         }
@@ -309,7 +291,7 @@ final class UnifiedPeerService: ObservableObject, TransportPeerEventsDelegate {
             var peerNostrKey = peer.nostrPublicKey
             if peerNostrKey == nil {
                 // Try to get from NostrIdentityBridge association
-                peerNostrKey = NostrIdentityBridge.getNostrPublicKey(for: peer.noisePublicKey)
+                peerNostrKey = idBridge.getNostrPublicKey(for: peer.noisePublicKey)
             }
             
             // Add favorite
@@ -340,39 +322,7 @@ final class UnifiedPeerService: ObservableObject, TransportPeerEventsDelegate {
         }
     }
     
-    /// Toggle blocked status
-    func toggleBlocked(_ peerID: String) {
-        guard let fingerprint = getFingerprint(for: peerID) else { return }
-        
-        // Get or create social identity
-        var identity = SecureIdentityStateManager.shared.getSocialIdentity(for: fingerprint)
-            ?? SocialIdentity(
-                fingerprint: fingerprint,
-                localPetname: nil,
-                claimedNickname: getPeer(by: peerID)?.displayName ?? "Unknown",
-                trustLevel: .unknown,
-                isFavorite: false,
-                isBlocked: false,
-                notes: nil
-            )
-        
-        // Toggle blocked status
-        identity.isBlocked = !identity.isBlocked
-        
-        // Can't be both favorite and blocked
-        if identity.isBlocked {
-            identity.isFavorite = false
-            // Also remove from favorites service
-            if let peer = getPeer(by: peerID) {
-                favoritesService.removeFavorite(peerNoisePublicKey: peer.noisePublicKey)
-            }
-        }
-        
-        SecureIdentityStateManager.shared.updateSocialIdentity(identity)
-    }
-    
-    /// Get fingerprint for peer ID
-    func getFingerprint(for peerID: String) -> String? {
+    func getFingerprint(for peerID: PeerID) -> String? {
         // Check cache first
         if let cached = fingerprintCache[peerID] {
             return cached
@@ -397,23 +347,13 @@ final class UnifiedPeerService: ObservableObject, TransportPeerEventsDelegate {
     // MARK: - Compatibility Methods (for easy migration)
     
     var allPeers: [BitchatPeer] { peers }
-    var connectedPeers: [String] { Array(connectedPeerIDs) }
-    var favoritePeers: Set<String> { 
-        Set(favorites.compactMap { getFingerprint(for: $0.id) })
+    var connectedPeers: Set<PeerID> { connectedPeerIDs }
+    var favoritePeers: Set<String> {
+        Set(favorites.compactMap { getFingerprint(for: $0.peerID) })
     }
     var blockedUsers: Set<String> {
         Set(peers.compactMap { peer in
-            isBlocked(peer.id) ? getFingerprint(for: peer.id) : nil
+            isBlocked(peer.peerID) ? getFingerprint(for: peer.peerID) : nil
         })
     }
 }
-
-// MARK: - Helper Extensions
-
-extension Data {
-    func sha256Fingerprint() -> String {
-        // Implementation matches existing fingerprint generation in NoiseEncryptionService
-        let hash = SHA256.hash(data: self)
-        return hash.map { String(format: "%02x", $0) }.joined()
-    }
-}

bitchat/Services/VerificationService.swift

@@ -1,5 +1,4 @@
 import Foundation
-import CryptoKit
 
 /// QR verification scaffolding: schema, signing, and basic challenge/response helpers.
 final class VerificationService {
@@ -95,7 +94,7 @@ final class VerificationService {
                                     nickname: payload.nickname,
                                     ts: payload.ts,
                                     nonceB64: payload.nonceB64,
-                                    sigHex: sig.map { String(format: "%02x", $0) }.joined())
+                                    sigHex: sig.hexEncodedString())
         let out = signed.toURLString()
         Cache.last = (nickname, npub, Date(), out)
         return out

bitchat/Sync/GCSFilter.swift

@@ -0,0 +1,237 @@
+import Foundation
+import CryptoKit
+
+// Golomb-Coded Set (GCS) filter utilities for sync.
+// Hashing:
+//  - Packet ID is 16 bytes (see PacketIdUtil). For GCS mapping, use h64 = first 8 bytes of SHA-256 over the 16-byte ID.
+//  - Map to [1, M) by computing (h64 % M) and remapping 0 -> 1 to avoid zero-length deltas.
+// Encoding (v1):
+//  - Sort mapped values ascending; encode deltas (first is v0, then vi - v{i-1}) as positive integers x >= 1.
+//  - Golomb-Rice with parameter P: q = (x - 1) >> P encoded as unary (q ones then a zero), then write P-bit remainder r = (x - 1) & ((1<<P)-1).
+//  - Bitstream is MSB-first within each byte.
+enum GCSFilter {
+    struct Params { let p: Int; let m: UInt32; let data: Data }
+
+    // Derive P from FPR (~ 1 / 2^P)
+    static func deriveP(targetFpr: Double) -> Int {
+        let f = max(0.000001, min(0.25, targetFpr))
+        // ceil(log2(1/f))
+        let p = Int(ceil(log2(1.0 / f)))
+        return max(1, p)
+    }
+
+    // Estimate max elements that fit in size bytes: bits per element ~= P + 2 (approx)
+    static func estimateMaxElements(sizeBytes: Int, p: Int) -> Int {
+        let bits = max(8, sizeBytes * 8)
+        let per = max(3, p + 2)
+        return max(1, bits / per)
+    }
+
+    static func buildFilter(ids: [Data], maxBytes: Int, targetFpr: Double) -> Params {
+        let p = deriveP(targetFpr: targetFpr)
+        guard !ids.isEmpty else {
+            return Params(p: p, m: 1, data: Data())
+        }
+
+        let cap = estimateMaxElements(sizeBytes: maxBytes, p: p)
+        let selected = Array(ids.prefix(cap))
+        let range = max(1, hashRange(count: selected.count, p: p))
+        let modulo = UInt64(range)
+
+        var mapped = selected
+            .map { h64($0) }
+            .map { mapHash($0, modulo: modulo) }
+            .sorted()
+        mapped = normalizeMappedValues(mapped, modulo: modulo)
+
+        if mapped.isEmpty {
+            return Params(p: p, m: range, data: Data())
+        }
+
+        var encoded = encode(sorted: mapped, p: p)
+        var trimmedCount = mapped.count
+
+        while encoded.count > maxBytes && trimmedCount > 0 {
+            if trimmedCount == 1 {
+                mapped.removeAll()
+                encoded = Data()
+                break
+            }
+            trimmedCount = max(1, (trimmedCount * 9) / 10)
+            mapped = Array(mapped.prefix(trimmedCount))
+            encoded = encode(sorted: mapped, p: p)
+        }
+
+        return Params(p: p, m: range, data: encoded)
+    }
+
+    static func decodeToSortedSet(p: Int, m: UInt32, data: Data) -> [UInt64] {
+        var values: [UInt64] = []
+        let reader = BitReader(data)
+        var acc: UInt64 = 0
+        while true {
+            guard let q = reader.readUnary() else { break }
+            guard let r = reader.readBits(count: p) else { break }
+            let x = (UInt64(q) << UInt64(p)) + UInt64(r) + 1
+            acc &+= x
+            if acc >= UInt64(m) { break }
+            values.append(acc)
+        }
+        return values
+    }
+
+    static func contains(sortedValues: [UInt64], candidate: UInt64) -> Bool {
+        var lo = 0
+        var hi = sortedValues.count - 1
+        while lo <= hi {
+            let mid = (lo + hi) >> 1
+            let v = sortedValues[mid]
+            if v == candidate { return true }
+            if v < candidate { lo = mid + 1 } else { hi = mid - 1 }
+        }
+        return false
+    }
+
+    static func bucket(for id: Data, modulus m: UInt32) -> UInt64 {
+        let modulo = UInt64(max(1, m))
+        guard modulo > 1 else { return 0 }
+        return mapHash(h64(id), modulo: modulo)
+    }
+
+    private static func h64(_ id16: Data) -> UInt64 {
+        var hasher = SHA256()
+        hasher.update(data: id16)
+        let d = hasher.finalize()
+        let db = Data(d)
+        var x: UInt64 = 0
+        let take = min(8, db.count)
+        for i in 0..<take { x = (x << 8) | UInt64(db[i]) }
+        return x & 0x7fff_ffff_ffff_ffff
+    }
+
+    private static func hashRange(count: Int, p: Int) -> UInt32 {
+        guard count > 0 else { return 1 }
+        if p >= 64 { return UInt32.max }
+        let multiplier = UInt64(1) << UInt64(p)
+        let (product, overflow) = UInt64(count).multipliedReportingOverflow(by: multiplier)
+        if overflow { return UInt32.max }
+        if product == 0 { return 1 }
+        return product > UInt64(UInt32.max) ? UInt32.max : UInt32(product)
+    }
+
+    private static func mapHash(_ hash: UInt64, modulo: UInt64) -> UInt64 {
+        guard modulo > 1 else { return 0 }
+        let value = hash % modulo
+        if value == 0 { return 1 }
+        return value
+    }
+
+    private static func normalizeMappedValues(_ values: [UInt64], modulo: UInt64) -> [UInt64] {
+        guard modulo > 1 else { return [] }
+        guard !values.isEmpty else { return [] }
+        var result: [UInt64] = []
+        result.reserveCapacity(values.count)
+        var last: UInt64 = 0
+        for value in values {
+            let normalized = min(value, modulo - 1)
+            if normalized > last {
+                result.append(normalized)
+                last = normalized
+            }
+        }
+        return result
+    }
+
+    private static func encode(sorted: [UInt64], p: Int) -> Data {
+        let writer = BitWriter()
+        var prev: UInt64 = 0
+        let mask: UInt64 = (p >= 64) ? ~0 : ((1 << UInt64(p)) - 1)
+        for v in sorted {
+            let delta = v &- prev
+            prev = v
+            let x = delta
+            let q = (x &- 1) >> UInt64(p)
+            let r = (x &- 1) & mask
+            // unary q ones then zero
+            if q > 0 { writer.writeOnes(count: Int(q)) }
+            writer.writeBit(0)
+            writer.writeBits(value: r, count: p)
+        }
+        return writer.toData()
+    }
+
+    // MARK: - Bit helpers (MSB-first)
+    private final class BitWriter {
+        private var buf = Data()
+        private var cur: UInt8 = 0
+        private var nbits: Int = 0
+        func writeBit(_ bit: Int) { // 0 or 1
+            cur = UInt8((Int(cur) << 1) | (bit & 1))
+            nbits += 1
+            if nbits == 8 {
+                buf.append(cur)
+                cur = 0; nbits = 0
+            }
+        }
+        func writeOnes(count: Int) {
+            guard count > 0 else { return }
+            for _ in 0..<count { writeBit(1) }
+        }
+        func writeBits(value: UInt64, count: Int) {
+            guard count > 0 else { return }
+            for i in stride(from: count - 1, through: 0, by: -1) {
+                let bit = Int((value >> UInt64(i)) & 1)
+                writeBit(bit)
+            }
+        }
+        func toData() -> Data {
+            if nbits > 0 {
+                let rem = UInt8(Int(cur) << (8 - nbits))
+                buf.append(rem)
+                cur = 0; nbits = 0
+            }
+            return buf
+        }
+    }
+
+    private final class BitReader {
+        private let data: Data
+        private var idx: Int = 0
+        private var cur: UInt8 = 0
+        private var left: Int = 0
+        init(_ data: Data) {
+            self.data = data
+            if !data.isEmpty {
+                cur = data[0]
+                left = 8
+            }
+        }
+        func readBit() -> Int? {
+            if idx >= data.count { return nil }
+            let bit = (Int(cur) >> 7) & 1
+            cur = UInt8((Int(cur) << 1) & 0xFF)
+            left -= 1
+            if left == 0 {
+                idx += 1
+                if idx < data.count { cur = data[idx]; left = 8 }
+            }
+            return bit
+        }
+        func readUnary() -> Int? {
+            var q = 0
+            while true {
+                guard let b = readBit() else { return nil }
+                if b == 1 { q += 1 } else { break }
+            }
+            return q
+        }
+        func readBits(count: Int) -> UInt64? {
+            var v: UInt64 = 0
+            for _ in 0..<count {
+                guard let b = readBit() else { return nil }
+                v = (v << 1) | UInt64(b)
+            }
+            return v
+        }
+    }
+}

bitchat/Sync/GossipSyncManager.swift

@@ -0,0 +1,435 @@
+import Foundation
+
+// Gossip-based sync manager using on-demand GCS filters
+final class GossipSyncManager {
+    protocol Delegate: AnyObject {
+        func sendPacket(_ packet: BitchatPacket)
+        func sendPacket(to peerID: PeerID, packet: BitchatPacket)
+        func signPacketForBroadcast(_ packet: BitchatPacket) -> BitchatPacket
+    }
+
+    private struct PacketStore {
+        private(set) var packets: [String: BitchatPacket] = [:]
+        private(set) var order: [String] = []
+
+        mutating func insert(idHex: String, packet: BitchatPacket, capacity: Int) {
+            guard capacity > 0 else { return }
+            if packets[idHex] != nil {
+                packets[idHex] = packet
+                return
+            }
+            packets[idHex] = packet
+            order.append(idHex)
+            while order.count > capacity {
+                let victim = order.removeFirst()
+                packets.removeValue(forKey: victim)
+            }
+        }
+
+        func allPackets(isFresh: (BitchatPacket) -> Bool) -> [BitchatPacket] {
+            order.compactMap { key in
+                guard let packet = packets[key], isFresh(packet) else { return nil }
+                return packet
+            }
+        }
+
+        mutating func remove(where shouldRemove: (BitchatPacket) -> Bool) {
+            var nextOrder: [String] = []
+            for key in order {
+                guard let packet = packets[key] else { continue }
+                if shouldRemove(packet) {
+                    packets.removeValue(forKey: key)
+                } else {
+                    nextOrder.append(key)
+                }
+            }
+            order = nextOrder
+        }
+
+        mutating func removeExpired(isFresh: (BitchatPacket) -> Bool) {
+            remove { !isFresh($0) }
+        }
+    }
+
+    private struct SyncSchedule {
+        let types: SyncTypeFlags
+        let interval: TimeInterval
+        var lastSent: Date
+    }
+
+    struct Config {
+        var seenCapacity: Int = 1000          // max packets per sync (cap across types)
+        var gcsMaxBytes: Int = 400           // filter size budget (128..1024)
+        var gcsTargetFpr: Double = 0.01      // 1%
+        var maxMessageAgeSeconds: TimeInterval = 900  // 15 min - discard older messages
+        var maintenanceIntervalSeconds: TimeInterval = 30.0
+        var stalePeerCleanupIntervalSeconds: TimeInterval = 60.0
+        var stalePeerTimeoutSeconds: TimeInterval = 60.0
+        var fragmentCapacity: Int = 600
+        var fileTransferCapacity: Int = 200
+        var fragmentSyncIntervalSeconds: TimeInterval = 30.0
+        var fileTransferSyncIntervalSeconds: TimeInterval = 60.0
+        var messageSyncIntervalSeconds: TimeInterval = 15.0
+    }
+
+    private let myPeerID: PeerID
+    private let config: Config
+    weak var delegate: Delegate?
+
+    // Storage: broadcast packets by type, and latest announce per sender
+    private var messages = PacketStore()
+    private var fragments = PacketStore()
+    private var fileTransfers = PacketStore()
+    private var latestAnnouncementByPeer: [PeerID: (id: String, packet: BitchatPacket)] = [:]
+
+    // Timer
+    private var periodicTimer: DispatchSourceTimer?
+    private let queue = DispatchQueue(label: "mesh.sync", qos: .utility)
+    private var lastStalePeerCleanup: Date = .distantPast
+    private var syncSchedules: [SyncSchedule] = []
+
+    init(myPeerID: PeerID, config: Config = Config()) {
+        self.myPeerID = myPeerID
+        self.config = config
+        var schedules: [SyncSchedule] = []
+        if config.seenCapacity > 0 && config.messageSyncIntervalSeconds > 0 {
+            schedules.append(SyncSchedule(types: .publicMessages, interval: config.messageSyncIntervalSeconds, lastSent: .distantPast))
+        }
+        if config.fragmentCapacity > 0 && config.fragmentSyncIntervalSeconds > 0 {
+            schedules.append(SyncSchedule(types: .fragment, interval: config.fragmentSyncIntervalSeconds, lastSent: .distantPast))
+        }
+        if config.fileTransferCapacity > 0 && config.fileTransferSyncIntervalSeconds > 0 {
+            schedules.append(SyncSchedule(types: .fileTransfer, interval: config.fileTransferSyncIntervalSeconds, lastSent: .distantPast))
+        }
+        syncSchedules = schedules
+    }
+
+    func start() {
+        stop()
+        let timer = DispatchSource.makeTimerSource(queue: queue)
+        let interval = max(0.1, config.maintenanceIntervalSeconds)
+        timer.schedule(deadline: .now() + interval, repeating: interval, leeway: .seconds(1))
+        timer.setEventHandler { [weak self] in
+            self?.performPeriodicMaintenance()
+        }
+        timer.resume()
+        periodicTimer = timer
+    }
+
+    func stop() {
+        periodicTimer?.cancel(); periodicTimer = nil
+    }
+
+    func scheduleInitialSyncToPeer(_ peerID: PeerID, delaySeconds: TimeInterval = 5.0) {
+        queue.asyncAfter(deadline: .now() + delaySeconds) { [weak self] in
+            guard let self = self else { return }
+            self.sendRequestSync(to: peerID, types: .publicMessages)
+            if self.config.fragmentCapacity > 0 && self.config.fragmentSyncIntervalSeconds > 0 {
+                self.queue.asyncAfter(deadline: .now() + 0.5) { [weak self] in
+                    self?.sendRequestSync(to: peerID, types: .fragment)
+                }
+            }
+            if self.config.fileTransferCapacity > 0 && self.config.fileTransferSyncIntervalSeconds > 0 {
+                self.queue.asyncAfter(deadline: .now() + 1.0) { [weak self] in
+                    self?.sendRequestSync(to: peerID, types: .fileTransfer)
+                }
+            }
+        }
+    }
+
+    func onPublicPacketSeen(_ packet: BitchatPacket) {
+        queue.async { [weak self] in
+            self?._onPublicPacketSeen(packet)
+        }
+    }
+
+    // Helper to check if a packet is within the age threshold
+    private func isPacketFresh(_ packet: BitchatPacket) -> Bool {
+        let nowMs = UInt64(Date().timeIntervalSince1970 * 1000)
+        let ageThresholdMs = UInt64(config.maxMessageAgeSeconds * 1000)
+
+        // If current time is less than threshold, accept all (handle clock issues gracefully)
+        guard nowMs >= ageThresholdMs else { return true }
+
+        let cutoffMs = nowMs - ageThresholdMs
+        return packet.timestamp >= cutoffMs
+    }
+
+    private func isAnnouncementFresh(_ packet: BitchatPacket) -> Bool {
+        guard config.stalePeerTimeoutSeconds > 0 else { return true }
+        let nowMs = UInt64(Date().timeIntervalSince1970 * 1000)
+        let timeoutMs = UInt64(config.stalePeerTimeoutSeconds * 1000)
+        guard nowMs >= timeoutMs else { return true }
+        let cutoffMs = nowMs - timeoutMs
+        return packet.timestamp >= cutoffMs
+    }
+
+    private func _onPublicPacketSeen(_ packet: BitchatPacket) {
+        guard let messageType = MessageType(rawValue: packet.type) else { return }
+        let isBroadcastRecipient: Bool = {
+            guard let r = packet.recipientID else { return true }
+            return r.count == 8 && r.allSatisfy { $0 == 0xFF }
+        }()
+
+        switch messageType {
+        case .announce:
+            guard isPacketFresh(packet) else { return }
+            guard isAnnouncementFresh(packet) else {
+                let sender = PeerID(hexData: packet.senderID)
+                removeState(for: sender)
+                return
+            }
+            let idHex = PacketIdUtil.computeId(packet).hexEncodedString()
+            let sender = PeerID(hexData: packet.senderID)
+            latestAnnouncementByPeer[sender] = (id: idHex, packet: packet)
+        case .message:
+            guard isBroadcastRecipient else { return }
+            guard isPacketFresh(packet) else { return }
+            let idHex = PacketIdUtil.computeId(packet).hexEncodedString()
+            messages.insert(idHex: idHex, packet: packet, capacity: max(1, config.seenCapacity))
+        case .fragment:
+            guard isBroadcastRecipient else { return }
+            guard isPacketFresh(packet) else { return }
+            let idHex = PacketIdUtil.computeId(packet).hexEncodedString()
+            fragments.insert(idHex: idHex, packet: packet, capacity: max(1, config.fragmentCapacity))
+        case .fileTransfer:
+            guard isBroadcastRecipient else { return }
+            guard isPacketFresh(packet) else { return }
+            let idHex = PacketIdUtil.computeId(packet).hexEncodedString()
+            fileTransfers.insert(idHex: idHex, packet: packet, capacity: max(1, config.fileTransferCapacity))
+        default:
+            break
+        }
+    }
+
+    private func sendRequestSync(for types: SyncTypeFlags) {
+        let payload = buildGcsPayload(for: types)
+        let pkt = BitchatPacket(
+            type: MessageType.requestSync.rawValue,
+            senderID: Data(hexString: myPeerID.id) ?? Data(),
+            recipientID: nil, // broadcast
+            timestamp: UInt64(Date().timeIntervalSince1970 * 1000),
+            payload: payload,
+            signature: nil,
+            ttl: 0 // local-only
+        )
+        let signed = delegate?.signPacketForBroadcast(pkt) ?? pkt
+        delegate?.sendPacket(signed)
+    }
+
+    private func sendRequestSync(to peerID: PeerID, types: SyncTypeFlags) {
+        let payload = buildGcsPayload(for: types)
+        var recipient = Data()
+        var temp = peerID.id
+        while temp.count >= 2 && recipient.count < 8 {
+            let hexByte = String(temp.prefix(2))
+            if let b = UInt8(hexByte, radix: 16) { recipient.append(b) }
+            temp = String(temp.dropFirst(2))
+        }
+        let pkt = BitchatPacket(
+            type: MessageType.requestSync.rawValue,
+            senderID: Data(hexString: myPeerID.id) ?? Data(),
+            recipientID: recipient,
+            timestamp: UInt64(Date().timeIntervalSince1970 * 1000),
+            payload: payload,
+            signature: nil,
+            ttl: 0 // local-only
+        )
+        let signed = delegate?.signPacketForBroadcast(pkt) ?? pkt
+        delegate?.sendPacket(to: peerID, packet: signed)
+    }
+
+    func handleRequestSync(from peerID: PeerID, request: RequestSyncPacket) {
+        queue.async { [weak self] in
+            self?._handleRequestSync(from: peerID, request: request)
+        }
+    }
+
+    private func _handleRequestSync(from peerID: PeerID, request: RequestSyncPacket) {
+        let requestedTypes = (request.types ?? .publicMessages)
+        // Decode GCS into sorted set and prepare membership checker
+        let sorted = GCSFilter.decodeToSortedSet(p: request.p, m: request.m, data: request.data)
+        func mightContain(_ id: Data) -> Bool {
+            let bucket = GCSFilter.bucket(for: id, modulus: request.m)
+            return GCSFilter.contains(sortedValues: sorted, candidate: bucket)
+        }
+
+        if requestedTypes.contains(.announce) {
+            for (_, pair) in latestAnnouncementByPeer {
+                let (idHex, pkt) = pair
+                guard isPacketFresh(pkt) else { continue }
+                let idBytes = Data(hexString: idHex) ?? Data()
+                if !mightContain(idBytes) {
+                    var toSend = pkt
+                    toSend.ttl = 0
+                    delegate?.sendPacket(to: peerID, packet: toSend)
+                }
+            }
+        }
+
+        if requestedTypes.contains(.message) {
+            let toSendMsgs = messages.allPackets(isFresh: isPacketFresh)
+            for pkt in toSendMsgs {
+                let idBytes = PacketIdUtil.computeId(pkt)
+                if !mightContain(idBytes) {
+                    var toSend = pkt
+                    toSend.ttl = 0
+                    delegate?.sendPacket(to: peerID, packet: toSend)
+                }
+            }
+        }
+
+        if requestedTypes.contains(.fragment) {
+            let frags = fragments.allPackets(isFresh: isPacketFresh)
+            for pkt in frags {
+                let idBytes = PacketIdUtil.computeId(pkt)
+                if !mightContain(idBytes) {
+                    var toSend = pkt
+                    toSend.ttl = 0
+                    delegate?.sendPacket(to: peerID, packet: toSend)
+                }
+            }
+        }
+
+        if requestedTypes.contains(.fileTransfer) {
+            let files = fileTransfers.allPackets(isFresh: isPacketFresh)
+            for pkt in files {
+                let idBytes = PacketIdUtil.computeId(pkt)
+                if !mightContain(idBytes) {
+                    var toSend = pkt
+                    toSend.ttl = 0
+                    delegate?.sendPacket(to: peerID, packet: toSend)
+                }
+            }
+        }
+    }
+
+    // Build REQUEST_SYNC payload using current candidates and GCS params
+    private func buildGcsPayload(for types: SyncTypeFlags) -> Data {
+        var candidates: [BitchatPacket] = []
+        if types.contains(.announce) {
+            for (_, pair) in latestAnnouncementByPeer where isPacketFresh(pair.packet) {
+                candidates.append(pair.packet)
+            }
+        }
+        if types.contains(.message) {
+            candidates.append(contentsOf: messages.allPackets(isFresh: isPacketFresh))
+        }
+        if types.contains(.fragment) {
+            candidates.append(contentsOf: fragments.allPackets(isFresh: isPacketFresh))
+        }
+        if types.contains(.fileTransfer) {
+            candidates.append(contentsOf: fileTransfers.allPackets(isFresh: isPacketFresh))
+        }
+        if candidates.isEmpty {
+            let p = GCSFilter.deriveP(targetFpr: config.gcsTargetFpr)
+            let req = RequestSyncPacket(p: p, m: 1, data: Data(), types: types)
+            return req.encode()
+        }
+
+        // Sort by timestamp desc
+        candidates.sort { $0.timestamp > $1.timestamp }
+
+        let p = GCSFilter.deriveP(targetFpr: config.gcsTargetFpr)
+        let nMax = GCSFilter.estimateMaxElements(sizeBytes: config.gcsMaxBytes, p: p)
+        let cap: Int
+        if types == .fragment {
+            cap = max(1, config.fragmentCapacity)
+        } else if types == .fileTransfer {
+            cap = max(1, config.fileTransferCapacity)
+        } else {
+            cap = max(1, config.seenCapacity)
+        }
+        let takeN = min(candidates.count, min(nMax, cap))
+        if takeN <= 0 {
+            let req = RequestSyncPacket(p: p, m: 1, data: Data(), types: types)
+            return req.encode()
+        }
+        let ids: [Data] = candidates.prefix(takeN).map { PacketIdUtil.computeId($0) }
+        let params = GCSFilter.buildFilter(ids: ids, maxBytes: config.gcsMaxBytes, targetFpr: config.gcsTargetFpr)
+        let req = RequestSyncPacket(p: params.p, m: params.m, data: params.data, types: types)
+        return req.encode()
+    }
+
+    // Periodic cleanup of expired messages and announcements
+    private func cleanupExpiredMessages() {
+        // Remove expired announcements
+        latestAnnouncementByPeer = latestAnnouncementByPeer.filter { _, pair in
+            isPacketFresh(pair.packet)
+        }
+
+        messages.removeExpired(isFresh: isPacketFresh)
+        fragments.removeExpired(isFresh: isPacketFresh)
+        fileTransfers.removeExpired(isFresh: isPacketFresh)
+    }
+
+    private func performPeriodicMaintenance(now: Date = Date()) {
+        cleanupExpiredMessages()
+        cleanupStaleAnnouncementsIfNeeded(now: now)
+        for index in syncSchedules.indices {
+            guard syncSchedules[index].interval > 0 else { continue }
+            if syncSchedules[index].lastSent == .distantPast || now.timeIntervalSince(syncSchedules[index].lastSent) >= syncSchedules[index].interval {
+                syncSchedules[index].lastSent = now
+                sendRequestSync(for: syncSchedules[index].types)
+            }
+        }
+    }
+
+    private func cleanupStaleAnnouncementsIfNeeded(now: Date) {
+        guard now.timeIntervalSince(lastStalePeerCleanup) >= config.stalePeerCleanupIntervalSeconds else {
+            return
+        }
+        lastStalePeerCleanup = now
+        cleanupStaleAnnouncements(now: now)
+    }
+
+    private func cleanupStaleAnnouncements(now: Date) {
+        let timeoutMs = UInt64(config.stalePeerTimeoutSeconds * 1000)
+        let nowMs = UInt64(now.timeIntervalSince1970 * 1000)
+        guard nowMs >= timeoutMs else { return }
+        let cutoff = nowMs - timeoutMs
+        let stalePeerIDs = latestAnnouncementByPeer.compactMap { peerID, pair in
+            pair.packet.timestamp < cutoff ? peerID : nil
+        }
+        guard !stalePeerIDs.isEmpty else { return }
+        for peerKey in stalePeerIDs {
+            removeState(for: peerKey)
+        }
+    }
+
+    // Explicit removal hook for LEAVE/stale peer
+    func removeAnnouncementForPeer(_ peerID: PeerID) {
+        queue.async { [weak self] in
+            self?.removeState(for: peerID)
+        }
+    }
+
+    private func removeState(for peerID: PeerID) {
+        _ = latestAnnouncementByPeer.removeValue(forKey: peerID)
+        messages.remove { PeerID(hexData: $0.senderID) == peerID }
+        fragments.remove { PeerID(hexData: $0.senderID) == peerID }
+        fileTransfers.remove { PeerID(hexData: $0.senderID) == peerID }
+    }
+}
+
+#if DEBUG
+extension GossipSyncManager {
+    func _performMaintenanceSynchronously(now: Date = Date()) {
+        queue.sync {
+            performPeriodicMaintenance(now: now)
+        }
+    }
+
+    func _hasAnnouncement(for peerID: PeerID) -> Bool {
+        queue.sync {
+            latestAnnouncementByPeer[peerID] != nil
+        }
+    }
+
+    func _messageCount(for peerID: PeerID) -> Int {
+        queue.sync {
+            messages.allPackets { _ in true }.filter { PeerID(hexData: $0.senderID) == peerID }.count
+        }
+    }
+}
+#endif

bitchat/Sync/PacketIdUtil.swift

@@ -0,0 +1,17 @@
+import Foundation
+import CryptoKit
+
+// Deterministic packet ID used for gossip sync membership
+// ID = first 16 bytes of SHA-256 over: [type | senderID | timestamp | payload]
+enum PacketIdUtil {
+    static func computeId(_ packet: BitchatPacket) -> Data {
+        var hasher = SHA256()
+        hasher.update(data: Data([packet.type]))
+        hasher.update(data: packet.senderID)
+        var tsBE = packet.timestamp.bigEndian
+        withUnsafeBytes(of: &tsBE) { raw in hasher.update(data: Data(raw)) }
+        hasher.update(data: packet.payload)
+        let digest = hasher.finalize()
+        return Data(digest.prefix(16))
+    }
+}

bitchat/Sync/SyncTypeFlags.swift

@@ -0,0 +1,104 @@
+import Foundation
+
+/// Bitfield describing which message types are covered by a REQUEST_SYNC round.
+/// Matches the Android mapping (bit index -> message type).
+struct SyncTypeFlags: OptionSet {
+    let rawValue: UInt64
+
+    init(rawValue: UInt64) {
+        self.rawValue = rawValue & 0x00FF_FFFF_FFFF_FFFF // Trim to max 8 bytes
+    }
+
+    private static func bitIndex(for type: MessageType) -> Int? {
+        switch type {
+        case .announce: return 0
+        case .message: return 1
+        case .leave: return 2
+        case .noiseHandshake: return 3
+        case .noiseEncrypted: return 4
+        case .fragment: return 5
+        case .requestSync: return 6
+        case .fileTransfer: return 7
+        }
+    }
+
+    private static func type(forBit index: Int) -> MessageType? {
+        switch index {
+        case 0: return .announce
+        case 1: return .message
+        case 2: return .leave
+        case 3: return .noiseHandshake
+        case 4: return .noiseEncrypted
+        case 5: return .fragment
+        case 6: return .requestSync
+        case 7: return .fileTransfer
+        default:
+            return nil
+        }
+    }
+
+    static let announce = SyncTypeFlags(messageTypes: [.announce])
+    static let message = SyncTypeFlags(messageTypes: [.message])
+    static let fragment = SyncTypeFlags(messageTypes: [.fragment])
+    static let fileTransfer = SyncTypeFlags(messageTypes: [.fileTransfer])
+
+    static let publicMessages = SyncTypeFlags(messageTypes: [.announce, .message])
+
+    init(messageTypes: [MessageType]) {
+        var raw: UInt64 = 0
+        for type in messageTypes {
+            guard let bit = SyncTypeFlags.bitIndex(for: type) else { continue }
+            raw |= (1 << UInt64(bit))
+        }
+        self.init(rawValue: raw)
+    }
+
+    func contains(_ type: MessageType) -> Bool {
+        guard let bit = SyncTypeFlags.bitIndex(for: type) else { return false }
+        return contains(SyncTypeFlags(rawValue: 1 << UInt64(bit)))
+    }
+
+    func union(_ other: SyncTypeFlags) -> SyncTypeFlags {
+        SyncTypeFlags(rawValue: rawValue | other.rawValue)
+    }
+
+    func intersection(_ other: SyncTypeFlags) -> SyncTypeFlags {
+        SyncTypeFlags(rawValue: rawValue & other.rawValue)
+    }
+
+    func toMessageTypes() -> [MessageType] {
+        guard rawValue != 0 else { return [] }
+        var types: [MessageType] = []
+        for bit in 0..<64 {
+            guard (rawValue & (1 << UInt64(bit))) != 0 else { continue }
+            if let type = SyncTypeFlags.type(forBit: bit) {
+                types.append(type)
+            }
+        }
+        return types
+    }
+
+    func toData() -> Data? {
+        guard rawValue != 0 else { return nil }
+        var value = rawValue
+        var bytes: [UInt8] = []
+        while value > 0 && bytes.count < 8 {
+            bytes.append(UInt8(value & 0xFF))
+            value >>= 8
+        }
+        while let last = bytes.last, last == 0 {
+            bytes.removeLast()
+        }
+        guard !bytes.isEmpty, bytes.count <= 8 else { return nil }
+        return Data(bytes)
+    }
+
+    static func decode(_ data: Data) -> SyncTypeFlags? {
+        guard (1...8).contains(data.count) else { return nil }
+        var raw: UInt64 = 0
+        for (index, byte) in data.enumerated() {
+            raw |= UInt64(byte) << UInt64(index * 8)
+        }
+        return SyncTypeFlags(rawValue: raw)
+    }
+}

bitchat/Utils/Color+Peer.swift

@@ -0,0 +1,37 @@
+//
+// Color+Peer.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import SwiftUI
+
+extension Color {
+    private static var peerColorCache: [String: Color] = [:]
+    
+    init(peerSeed: String, isDark: Bool) {
+        let cacheKey = peerSeed + (isDark ? "|dark" : "|light")
+        if let cached = Self.peerColorCache[cacheKey] {
+            self = cached
+        }
+        let h = peerSeed.djb2()
+        var hue = Double(h % 1000) / 1000.0
+        let orange = 30.0 / 360.0
+        if abs(hue - orange) < TransportConfig.uiColorHueAvoidanceDelta {
+            hue = fmod(hue + TransportConfig.uiColorHueOffset, 1.0)
+        }
+        let sRand = Double((h >> 17) & 0x3FF) / 1023.0
+        let bRand = Double((h >> 27) & 0x3FF) / 1023.0
+        let sBase: Double = isDark ? 0.80 : 0.70
+        let sRange: Double = 0.20
+        let bBase: Double = isDark ? 0.75 : 0.45
+        let bRange: Double = isDark ? 0.16 : 0.14
+        let saturation = min(1.0, max(0.50, sBase + (sRand - 0.5) * sRange))
+        let brightness = min(1.0, max(0.35, bBase + (bRand - 0.5) * bRange))
+        let c = Color(hue: hue, saturation: saturation, brightness: brightness)
+        Self.peerColorCache[cacheKey] = c
+        self = c
+    }
+}

bitchat/Utils/CompressionUtil.swift

@@ -61,15 +61,13 @@ struct CompressionUtil {
         // 1. Data is too small
         // 2. Data appears to be already compressed (high entropy)
         guard data.count >= compressionThreshold else { return false }
-        
-        // Simple entropy check - count unique bytes
-        var byteFrequency = [UInt8: Int]()
-        for byte in data {
-            byteFrequency[byte, default: 0] += 1
-        }
-        
-        // If we have very high byte diversity, data is likely already compressed
-        let uniqueByteRatio = Double(byteFrequency.count) / Double(min(data.count, 256))
+
+        // Quick uniqueness check — a high diversity of bytes usually means the
+        // payload is already compressed. We only need to know how many unique
+        // values exist rather than keeping full frequency counts.
+        let uniqueByteCount = Set(data).count
+        let sampleSize = min(data.count, 256)
+        let uniqueByteRatio = Double(uniqueByteCount) / Double(sampleSize)
         return uniqueByteRatio < 0.9 // Compress if less than 90% unique bytes
     }
 }

bitchat/Utils/Data+SHA256.swift

@@ -0,0 +1,22 @@
+//
+//  Data+SHA256.swift
+//  bitchat
+//
+//  Created by Islam on 26/09/2025.
+//
+
+import struct Foundation.Data
+import struct CryptoKit.SHA256
+
+extension Data {
+    /// Returns the hex representation of SHA256 hash
+    func sha256Fingerprint() -> String {
+        // Implementation matches existing fingerprint generation in NoiseEncryptionService
+        sha256Hash().hexEncodedString()
+    }
+    
+    /// Returns the SHA256 hash wrapped in Data
+    func sha256Hash() -> Data {
+        Data(SHA256.hash(data: self))
+    }
+}

bitchat/Utils/FileTransferLimits.swift

@@ -0,0 +1,25 @@
+import Foundation
+
+/// Centralized thresholds for Bluetooth file transfers to keep payload sizes sane on constrained radios.
+enum FileTransferLimits {
+    /// Absolute ceiling enforced for any file payload (voice, image, other).
+    static let maxPayloadBytes: Int = 1 * 1024 * 1024 // 1 MiB
+    /// Voice notes stay small for low-latency relays.
+    static let maxVoiceNoteBytes: Int = 512 * 1024 // 512 KiB
+    /// Compressed images after downscaling should comfortably fit under this budget.
+    static let maxImageBytes: Int = 512 * 1024 // 512 KiB
+    /// Worst-case size once TLV metadata and binary packet framing are included for the largest payloads.
+    static let maxFramedFileBytes: Int = {
+        let maxMetadataBytes = Int(UInt16.max) * 2 // fileName + mimeType TLVs
+        let tlvEnvelopeOverhead = 18 + maxMetadataBytes // TLV tags + lengths + metadata bytes
+        let binaryEnvelopeOverhead = BinaryProtocol.v2HeaderSize
+            + BinaryProtocol.senderIDSize
+            + BinaryProtocol.recipientIDSize
+            + BinaryProtocol.signatureSize
+        return maxPayloadBytes + tlvEnvelopeOverhead + binaryEnvelopeOverhead
+    }()
+
+    static func isValidPayload(_ size: Int) -> Bool {
+        size <= maxPayloadBytes
+    }
+}

bitchat/Utils/Font+Bitchat.swift

@@ -0,0 +1,41 @@
+import SwiftUI
+
+/// Provides Dynamic Type aware font helpers that map existing fixed sizes onto
+/// preferred text styles so the UI scales with user accessibility settings.
+extension Font {
+    static func bitchatSystem(size: CGFloat, weight: Font.Weight = .regular, design: Font.Design = .default) -> Font {
+        let style = Font.TextStyle.bitchatPreferredStyle(for: size)
+        var font = Font.system(style, design: design)
+        if weight != .regular {
+            font = font.weight(weight)
+        }
+        return font
+    }
+}
+
+private extension Font.TextStyle {
+    static func bitchatPreferredStyle(for size: CGFloat) -> Font.TextStyle {
+        switch size {
+        case ..<11.5:
+            return .caption2
+        case ..<13.0:
+            return .caption
+        case ..<13.75:
+            return .footnote
+        case ..<15.5:
+            return .subheadline
+        case ..<17.5:
+            return .callout
+        case ..<19.5:
+            return .body
+        case ..<22.5:
+            return .title3
+        case ..<27.5:
+            return .title2
+        case ..<34.0:
+            return .title
+        default:
+            return .largeTitle
+        }
+    }
+}

bitchat/Utils/InputValidator.swift

@@ -1,4 +1,5 @@
 import Foundation
+import BitLogger
 
 /// Comprehensive input validation for BitChat protocol
 /// Prevents injection attacks, buffer overflows, and malformed data
@@ -8,89 +9,48 @@ struct InputValidator {
     
     struct Limits {
         static let maxNicknameLength = 50
-        static let maxMessageLength = 10_000
-        static let maxReasonLength = 200
-        static let maxPeerIDLength = 64
-        static let hexPeerIDLength = 16 // 8 bytes = 16 hex chars
-    }
-    
-    // MARK: - Peer ID Validation
-    
-    /// Validates a peer ID from any source (short 16-hex, full 64-hex, or internal alnum/-/_ up to 64)
-    static func validatePeerID(_ peerID: String) -> Bool {
-        // Accept short routing IDs (exact 16-hex)
-        if PeerIDResolver.isShortID(peerID) { return true }
-        // If length equals short-hex length but isn't valid hex, reject
-        if peerID.count == Limits.hexPeerIDLength { return false }
-        // Accept full Noise key hex (exact 64-hex)
-        if PeerIDResolver.isNoiseKeyHex(peerID) { return true }
-        // If length equals full key length but isn't valid hex, reject
-        if peerID.count == Limits.maxPeerIDLength { return false }
-        // Internal format: alphanumeric + dash/underscore up to 63 (not 16 or 64)
-        let validCharset = CharacterSet.alphanumerics.union(CharacterSet(charactersIn: "-_"))
-        return !peerID.isEmpty &&
-               peerID.count < Limits.maxPeerIDLength &&
-               peerID.rangeOfCharacter(from: validCharset.inverted) == nil
+        // BinaryProtocol caps payload length at UInt16.max (65_535). Leave headroom
+        // for headers/padding by limiting user content to 60_000 bytes.
+        static let maxMessageLength = 60_000
     }
     
     // MARK: - String Content Validation
     
-    /// Validates and sanitizes user-provided strings (nicknames, messages)
-    static func validateUserString(_ string: String, maxLength: Int, allowNewlines: Bool = false) -> String? {
-        // Check empty
-        guard !string.isEmpty else { return nil }
-        
-        // Trim whitespace
+    /// Validates and sanitizes user-provided strings used in UI
+    ///
+    /// Rejects strings containing control characters to prevent potential security issues
+    /// and UI rendering problems. This strict approach ensures data integrity at input time.
+    static func validateUserString(_ string: String, maxLength: Int) -> String? {
         let trimmed = string.trimmingCharacters(in: .whitespacesAndNewlines)
         guard !trimmed.isEmpty else { return nil }
-        
-        // Check length
         guard trimmed.count <= maxLength else { return nil }
-        
-        // Remove control characters except allowed ones
-        var allowedControlChars = CharacterSet()
-        if allowNewlines {
-            allowedControlChars.insert(charactersIn: "\n\r")
+
+        // Reject control characters outright instead of rewriting the string.
+        // This prevents injection attacks and ensures consistent UI rendering.
+        let controlChars = CharacterSet.controlCharacters
+        if !trimmed.unicodeScalars.allSatisfy({ !controlChars.contains($0) }) {
+            // Log rejection for monitoring, without exposing actual content for privacy
+            let controlCharCount = trimmed.unicodeScalars.filter { controlChars.contains($0) }.count
+            SecureLogger.debug(
+                "Input validation rejected string (length: \(trimmed.count), control chars: \(controlCharCount))",
+                category: .security
+            )
+            return nil
         }
-        
-        let controlChars = CharacterSet.controlCharacters.subtracting(allowedControlChars)
-        let cleaned = trimmed.components(separatedBy: controlChars).joined()
-        
-        // Ensure valid UTF-8 (should already be, but double-check)
-        guard cleaned.data(using: .utf8) != nil else { return nil }
-        
-        // Prevent zero-width characters and other invisible unicode
-        let invisibleChars = CharacterSet(charactersIn: "\u{200B}\u{200C}\u{200D}\u{FEFF}")
-        let visible = cleaned.components(separatedBy: invisibleChars).joined()
-        
-        return visible.isEmpty ? nil : visible
+
+        return trimmed
     }
     
     /// Validates nickname
     static func validateNickname(_ nickname: String) -> String? {
-        return validateUserString(nickname, maxLength: Limits.maxNicknameLength, allowNewlines: false)
-    }
-    
-    /// Validates message content
-    static func validateMessageContent(_ content: String) -> String? {
-        return validateUserString(content, maxLength: Limits.maxMessageLength, allowNewlines: true)
-    }
-    
-    /// Validates error/reason strings
-    static func validateReasonString(_ reason: String) -> String? {
-        return validateUserString(reason, maxLength: Limits.maxReasonLength, allowNewlines: false)
+        return validateUserString(nickname, maxLength: Limits.maxNicknameLength)
     }
     
     // MARK: - Protocol Field Validation
-    
+
     // Note: Message type validation is performed closer to decoding using
     // MessageType/NoisePayloadType enums; keeping validator free of stale lists.
-    
-    /// Validates hop count is reasonable
-    static func validateHopCount(_ hopCount: UInt8) -> Bool {
-        return hopCount <= 10 // Prevent excessive forwarding
-    }
-    
+
     /// Validates timestamp is reasonable (not too far in past or future)
     static func validateTimestamp(_ timestamp: Date) -> Bool {
         let now = Date()
@@ -98,38 +58,5 @@ struct InputValidator {
         let oneHourFromNow = now.addingTimeInterval(3600)
         return timestamp >= oneHourAgo && timestamp <= oneHourFromNow
     }
-    
-    /// Validates data size for different contexts
-    static func validateDataSize(_ data: Data, maxSize: Int) -> Bool {
-        return data.count > 0 && data.count <= maxSize
-    }
-    
-    // MARK: - Binary Data Validation
-    
-    /// Validates UUID format
-    static func validateUUID(_ uuid: String) -> Bool {
-        // Remove dashes and validate hex
-        let cleaned = uuid.replacingOccurrences(of: "-", with: "")
-        return cleaned.count == 32 && cleaned.allSatisfy { $0.isHexDigit }
-    }
-    
-    /// Validates public key data
-    static func validatePublicKey(_ keyData: Data) -> Bool {
-        // Curve25519 public keys are 32 bytes
-        return keyData.count == 32
-    }
-    
-    /// Validates signature data
-    static func validateSignature(_ signature: Data) -> Bool {
-        // Ed25519 signatures are 64 bytes
-        return signature.count == 64
-    }
-}
 
-// MARK: - Character Extensions
-
-private extension Character {
-    var isHexDigit: Bool {
-        return "0123456789abcdefABCDEF".contains(self)
-    }
 }

bitchat/Utils/PeerDisplayNameResolver.swift

@@ -4,10 +4,10 @@ import Foundation
 struct PeerDisplayNameResolver {
     /// Computes display names with a `#xxxx` suffix for connected peers when nickname collisions occur.
     /// - Parameters:
-    ///   - peers: Array of tuples (id, nickname, isConnected).
+    ///   - peers: Array of tuples (peerID, nickname, isConnected).
     ///   - selfNickname: The local user's current nickname, included in collision counts to suffix remotes matching it.
     /// - Returns: Map of peerID -> displayName.
-    static func resolve(_ peers: [(id: String, nickname: String, isConnected: Bool)], selfNickname: String) -> [String: String] {
+    static func resolve(_ peers: [(peerID: PeerID, nickname: String, isConnected: Bool)], selfNickname: String) -> [PeerID: String] {
         // Count collisions among connected peers and include our own nickname
         var counts: [String: Int] = [:]
         for p in peers where p.isConnected {
@@ -15,13 +15,13 @@ struct PeerDisplayNameResolver {
         }
         counts[selfNickname, default: 0] += 1
 
-        var result: [String: String] = [:]
+        var result: [PeerID: String] = [:]
         for p in peers {
             var name = p.nickname
             if p.isConnected, (counts[p.nickname] ?? 0) > 1 {
-                name += "#" + String(p.id.prefix(4))
+                name += "#" + String(p.peerID.id.prefix(4))
             }
-            result[p.id] = name
+            result[p.peerID] = name
         }
         return result
     }

bitchat/Utils/PeerIDResolver.swift

@@ -1,20 +0,0 @@
-import Foundation
-
-struct PeerIDResolver {
-    /// Returns a 16-hex short peer ID derived from a 64-hex Noise public key if needed
-    static func toShortID(_ id: String) -> String {
-        if id.count == 64, let data = Data(hexString: id) {
-            return PeerIDUtils.derivePeerID(fromPublicKey: data)
-        }
-        return id
-    }
-
-    static func isShortID(_ id: String) -> Bool {
-        return id.count == 16 && Data(hexString: id) != nil
-    }
-
-    static func isNoiseKeyHex(_ id: String) -> Bool {
-        return id.count == 64 && Data(hexString: id) != nil
-    }
-}
-

bitchat/Utils/String+DJB2.swift

@@ -0,0 +1,17 @@
+//
+// String+DJB2.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+
+extension String {
+    func djb2() -> UInt64 {
+        var hash: UInt64 = 5381
+        for b in utf8 { hash = ((hash << 5) &+ hash) &+ UInt64(b) }
+        return hash
+    }
+}

bitchat/Utils/String+Nickname.swift

@@ -0,0 +1,25 @@
+//
+// String+Nickname.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+
+extension String {
+    /// Split a nickname into base and a '#abcd' suffix if present
+    func splitSuffix() -> (String, String) {
+        let name = self.replacingOccurrences(of: "@", with: "")
+        guard name.count >= 5 else { return (name, "") }
+        let suffix = String(name.suffix(5))
+        if suffix.first == "#", suffix.dropFirst().allSatisfy({ c in
+            ("0"..."9").contains(String(c)) || ("a"..."f").contains(String(c)) || ("A"..."F").contains(String(c))
+        }) {
+            let base = String(name.dropLast(5))
+            return (base, suffix)
+        }
+        return (name, "")
+    }
+}

bitchat/Views/AppInfoView.swift

@@ -18,41 +18,77 @@ struct AppInfoView: View {
     
     // MARK: - Constants
     private enum Strings {
-        static let appName = "bitchat"
-        static let tagline = "sidegroupchat"
-        
+        static let appName: LocalizedStringKey = "app_info.app_name"
+        static let tagline: LocalizedStringKey = "app_info.tagline"
+
         enum Features {
-            static let title = "FEATURES"
-            static let offlineComm = ("wifi.slash", "offline communication", "works without internet using Bluetooth low energy")
-            static let encryption = ("lock.shield", "end-to-end encryption", "private messages encrypted with noise protocol")
-            static let extendedRange = ("antenna.radiowaves.left.and.right", "extended range", "messages relay through peers, going the distance")
-            static let mentions = ("at", "mentions", "use @nickname to notify specific people")
-            static let favorites = ("star.fill", "favorites", "get notified when your favorite people join")
-            static let geohash = ("number", "local channels", "geohash channels to chat with people in nearby regions over decentralized anonymous relays")
+            static let title: LocalizedStringKey = "app_info.features.title"
+            static let offlineComm = AppInfoFeatureInfo(
+                icon: "wifi.slash",
+                title: "app_info.features.offline.title",
+                description: "app_info.features.offline.description"
+            )
+            static let encryption = AppInfoFeatureInfo(
+                icon: "lock.shield",
+                title: "app_info.features.encryption.title",
+                description: "app_info.features.encryption.description"
+            )
+            static let extendedRange = AppInfoFeatureInfo(
+                icon: "antenna.radiowaves.left.and.right",
+                title: "app_info.features.extended_range.title",
+                description: "app_info.features.extended_range.description"
+            )
+            static let mentions = AppInfoFeatureInfo(
+                icon: "at",
+                title: "app_info.features.mentions.title",
+                description: "app_info.features.mentions.description"
+            )
+            static let favorites = AppInfoFeatureInfo(
+                icon: "star.fill",
+                title: "app_info.features.favorites.title",
+                description: "app_info.features.favorites.description"
+            )
+            static let geohash = AppInfoFeatureInfo(
+                icon: "number",
+                title: "app_info.features.geohash.title",
+                description: "app_info.features.geohash.description"
+            )
         }
-        
+
         enum Privacy {
-            static let title = "PRIVACY"
-            static let noTracking = ("eye.slash", "no tracking", "no servers, accounts, or data collection")
-            static let ephemeral = ("shuffle", "ephemeral identity", "new peer ID generated regularly")
-            static let panic = ("hand.raised.fill", "panic mode", "triple-tap logo to instantly clear all data")
+            static let title: LocalizedStringKey = "app_info.privacy.title"
+            static let noTracking = AppInfoFeatureInfo(
+                icon: "eye.slash",
+                title: "app_info.privacy.no_tracking.title",
+                description: "app_info.privacy.no_tracking.description"
+            )
+            static let ephemeral = AppInfoFeatureInfo(
+                icon: "shuffle",
+                title: "app_info.privacy.ephemeral.title",
+                description: "app_info.privacy.ephemeral.description"
+            )
+            static let panic = AppInfoFeatureInfo(
+                icon: "hand.raised.fill",
+                title: "app_info.privacy.panic.title",
+                description: "app_info.privacy.panic.description"
+            )
         }
-        
+
         enum HowToUse {
-            static let title = "HOW TO USE"
-            static let instructions = [
-                "• set your nickname by tapping it",
-                "• tap #mesh to change channels",
-                "• tap people icon for sidebar",
-                "• tap a peer's name to start a DM",
-                "• triple-tap chat to clear",
-                "• type / for commands"
+            static let title: LocalizedStringKey = "app_info.how_to_use.title"
+            static let instructions: [LocalizedStringKey] = [
+                "app_info.how_to_use.set_nickname",
+                "app_info.how_to_use.change_channels",
+                "app_info.how_to_use.open_sidebar",
+                "app_info.how_to_use.start_dm",
+                "app_info.how_to_use.clear_chat",
+                "app_info.how_to_use.commands"
             ]
         }
-        
+
         enum Warning {
-            static let title = "WARNING"
-            static let message = "private message security has not yet been fully audited. do not use for critical situations until this warning disappears."
+            static let title: LocalizedStringKey = "app_info.warning.title"
+            static let message: LocalizedStringKey = "app_info.warning.message"
         }
     }
     
@@ -62,7 +98,7 @@ struct AppInfoView: View {
             // Custom header for macOS
             HStack {
                 Spacer()
-                Button("DONE") {
+                Button("app_info.done") {
                     dismiss()
                 }
                 .buttonStyle(.plain)
@@ -86,10 +122,14 @@ struct AppInfoView: View {
             .navigationBarTitleDisplayMode(.inline)
             .toolbar {
                 ToolbarItem(placement: .navigationBarTrailing) {
-                    Button("close") {
-                        dismiss()
+                    Button(action: { dismiss() }) {
+                        Image(systemName: "xmark")
+                            .font(.bitchatSystem(size: 13, weight: .semibold, design: .monospaced))
+                            .foregroundColor(textColor)
+                            .frame(width: 32, height: 32)
                     }
-                    .foregroundColor(textColor)
+                    .buttonStyle(.plain)
+                    .accessibilityLabel("app_info.close")
                 }
             }
         }
@@ -102,82 +142,64 @@ struct AppInfoView: View {
             // Header
             VStack(alignment: .center, spacing: 8) {
                 Text(Strings.appName)
-                    .font(.system(size: 32, weight: .bold, design: .monospaced))
+                    .font(.bitchatSystem(size: 32, weight: .bold, design: .monospaced))
                     .foregroundColor(textColor)
                 
                 Text(Strings.tagline)
-                    .font(.system(size: 16, design: .monospaced))
+                    .font(.bitchatSystem(size: 16, design: .monospaced))
                     .foregroundColor(secondaryTextColor)
             }
             .frame(maxWidth: .infinity)
             .padding(.vertical)
             
-            // Features
-            VStack(alignment: .leading, spacing: 16) {
-                SectionHeader(Strings.Features.title)
-                
-                FeatureRow(icon: Strings.Features.offlineComm.0, 
-                          title: Strings.Features.offlineComm.1,
-                          description: Strings.Features.offlineComm.2)
-                
-                FeatureRow(icon: Strings.Features.encryption.0,
-                          title: Strings.Features.encryption.1,
-                          description: Strings.Features.encryption.2)
-                
-                FeatureRow(icon: Strings.Features.extendedRange.0,
-                          title: Strings.Features.extendedRange.1,
-                          description: Strings.Features.extendedRange.2)
-                
-                FeatureRow(icon: Strings.Features.favorites.0,
-                          title: Strings.Features.favorites.1,
-                          description: Strings.Features.favorites.2)
-                
-                FeatureRow(icon: Strings.Features.geohash.0,
-                          title: Strings.Features.geohash.1,
-                          description: Strings.Features.geohash.2)
-                
-                FeatureRow(icon: Strings.Features.mentions.0,
-                          title: Strings.Features.mentions.1,
-                          description: Strings.Features.mentions.2)
-            }
-            
-            // Privacy
-            VStack(alignment: .leading, spacing: 16) {
-                SectionHeader(Strings.Privacy.title)
-                
-                FeatureRow(icon: Strings.Privacy.noTracking.0,
-                          title: Strings.Privacy.noTracking.1,
-                          description: Strings.Privacy.noTracking.2)
-                
-                FeatureRow(icon: Strings.Privacy.ephemeral.0,
-                          title: Strings.Privacy.ephemeral.1,
-                          description: Strings.Privacy.ephemeral.2)
-                
-                FeatureRow(icon: Strings.Privacy.panic.0,
-                          title: Strings.Privacy.panic.1,
-                          description: Strings.Privacy.panic.2)
-            }
-            
             // How to Use
             VStack(alignment: .leading, spacing: 16) {
                 SectionHeader(Strings.HowToUse.title)
-                
+
                 VStack(alignment: .leading, spacing: 8) {
-                    ForEach(Strings.HowToUse.instructions, id: \.self) { instruction in
+                    ForEach(Array(Strings.HowToUse.instructions.enumerated()), id: \.offset) { _, instruction in
                         Text(instruction)
                     }
                 }
-                .font(.system(size: 14, design: .monospaced))
+                .font(.bitchatSystem(size: 14, design: .monospaced))
                 .foregroundColor(textColor)
             }
-            
+
+            // Features
+            VStack(alignment: .leading, spacing: 16) {
+                SectionHeader(Strings.Features.title)
+
+                FeatureRow(info: Strings.Features.offlineComm)
+
+                FeatureRow(info: Strings.Features.encryption)
+
+                FeatureRow(info: Strings.Features.extendedRange)
+
+                FeatureRow(info: Strings.Features.favorites)
+
+                FeatureRow(info: Strings.Features.geohash)
+
+                FeatureRow(info: Strings.Features.mentions)
+            }
+
+            // Privacy
+            VStack(alignment: .leading, spacing: 16) {
+                SectionHeader(Strings.Privacy.title)
+
+                FeatureRow(info: Strings.Privacy.noTracking)
+
+                FeatureRow(info: Strings.Privacy.ephemeral)
+
+                FeatureRow(info: Strings.Privacy.panic)
+            }
+
             // Warning
             VStack(alignment: .leading, spacing: 6) {
                 SectionHeader(Strings.Warning.title)
                     .foregroundColor(Color.red)
                 
                 Text(Strings.Warning.message)
-                    .font(.system(size: 14, design: .monospaced))
+                    .font(.bitchatSystem(size: 14, design: .monospaced))
                     .foregroundColor(Color.red)
                     .fixedSize(horizontal: false, vertical: true)
             }
@@ -193,30 +215,34 @@ struct AppInfoView: View {
     }
 }
 
+struct AppInfoFeatureInfo {
+    let icon: String
+    let title: LocalizedStringKey
+    let description: LocalizedStringKey
+}
+
 struct SectionHeader: View {
-    let title: String
+    let title: LocalizedStringKey
     @Environment(\.colorScheme) var colorScheme
     
     private var textColor: Color {
         colorScheme == .dark ? Color.green : Color(red: 0, green: 0.5, blue: 0)
     }
     
-    init(_ title: String) {
+    init(_ title: LocalizedStringKey) {
         self.title = title
     }
     
     var body: some View {
         Text(title)
-            .font(.system(size: 16, weight: .bold, design: .monospaced))
+            .font(.bitchatSystem(size: 16, weight: .bold, design: .monospaced))
             .foregroundColor(textColor)
             .padding(.top, 8)
     }
 }
 
 struct FeatureRow: View {
-    let icon: String
-    let title: String
-    let description: String
+    let info: AppInfoFeatureInfo
     @Environment(\.colorScheme) var colorScheme
     
     private var textColor: Color {
@@ -229,18 +255,18 @@ struct FeatureRow: View {
     
     var body: some View {
         HStack(alignment: .top, spacing: 12) {
-            Image(systemName: icon)
-                .font(.system(size: 20))
+            Image(systemName: info.icon)
+                .font(.bitchatSystem(size: 20))
                 .foregroundColor(textColor)
                 .frame(width: 30)
             
             VStack(alignment: .leading, spacing: 4) {
-                Text(title)
-                    .font(.system(size: 14, weight: .semibold, design: .monospaced))
+                Text(info.title)
+                    .font(.bitchatSystem(size: 14, weight: .semibold, design: .monospaced))
                     .foregroundColor(textColor)
                 
-                Text(description)
-                    .font(.system(size: 12, design: .monospaced))
+                Text(info.description)
+                    .font(.bitchatSystem(size: 12, design: .monospaced))
                     .foregroundColor(secondaryTextColor)
                     .fixedSize(horizontal: false, vertical: true)
             }
@@ -250,6 +276,16 @@ struct FeatureRow: View {
     }
 }
 
-#Preview {
+#Preview("Default") {
     AppInfoView()
 }
+
+#Preview("Dynamic Type XXL") {
+    AppInfoView()
+        .environment(\.sizeCategory, .accessibilityExtraExtraExtraLarge)
+}
+
+#Preview("Dynamic Type XS") {
+    AppInfoView()
+        .environment(\.sizeCategory, .extraSmall)
+}