b09710a7aa Feature/location channels (#459)
* Require signed announces; add Ed25519 key/signature/timestamp TLVs and verify

- Protocol: AnnouncementPacket now requires ed25519PublicKey (0x03), announceSignature (0x04), and announceTimestamp (0x05). Encoder emits, decoder requires; unknown TLVs still tolerated.
- NoiseEncryptionService: add canonical announce sign/verify helpers using context 'bitchat-announce-v1'.
- BLEService: sign Announce, include TLVs; on receive verify (±5 min skew) and ignore unverified; store ed25519 key and isVerifiedNickname in PeerInfo.
- Preserve 8-byte on-wire IDs to keep BLE headers small; no per-message bloat.

* Fix Data.append usage for timestamp bytes in Packets and NoiseEncryptionService (use append(contentsOf:) on UnsafeRawBufferPointer)

* BLEService: fix non-optional announce fields and unwrap signature result; enforce required verification path

* Enforce verified-only public messages; append peerID suffix on nickname collisions in handleMessage

* Suffix duplicate nicknames with peerID prefix in snapshots and getPeerNicknames; ensures lists and messages disambiguate 'jack' vs 'jack'

* Include self nickname in collision detection: suffix remote 'jack' when it matches our nickname in lists and public chat

* UI labels: remove space before '#abcd' suffix in names (public chat, peer lists, snapshots)

* Style '#abcd' suffix light gray:
- Public chat: color suffix in sender via AttributedString segments
- People list: split name and color suffix segment; add helper splitNameSuffix()

* Debounce 'bitchatters nearby' notification: add 60s grace before reset when mesh goes empty; cancel reset when peers return

* Lighten '#abcd' suffix: use Color.secondary.opacity(0.6) in public chat sender and People list

* Toolbar peers indicator: use blue when Bluetooth peers present (was default text color)

* Toolbar peers indicator: use grey when zero peers (was red)

* Toolbar peers indicator: use system grey (Color.secondary) when zero peers, not green

* Fix crash: mutate peripherals dict on BLE queue (not main). Move scan restart to BLE queue as well.

* Reduce connect timeout churn: back off peripherals that time out (15s), increase timeout to 8s, skip non-connectable adverts, and demote timeout log to debug; clean backoff map periodically

* Mentions: support '@name#abcd' disambiguation; filter hashtag/URL styling inside mentions; deliver notifications only to the specified suffixed target when collisions exist

* Fix string interpolation in mention log (escape sequence)

* Mentions: parse '@name#abcd' in sender/receiver; render mention suffix grey (not orange/blue/underlined); ensure receiver notifications trigger for suffixed tokens

* Mentions: include own suffixed token 'name#<myIDprefix>' in valid tokens so '@name#abcd' to self is recognized and notified

* Public actions: show own system message by processing own public messages (remove early-return). Private /hug: add local system message for sender's chat.

* Grammar: change local '/hug' message to past tense ('you hugged/slapped'). Notifications: only fire 'bitchatters nearby' on rising-edge; remove 5-min re-fire and increase empty reset grace to 10m.

* Public /hug echo: add local system message so sender sees action immediately (no reliance on echo)

* Fix visibility: expose addPublicSystemMessage on ChatViewModel and use it from CommandProcessor

* Implement iOS Location Channels (geohash public chats)

- Domain: add ChannelID, GeohashChannel(Level), lightweight geohash encoder
- Identity: derive per-geohash Nostr keys (HMAC-SHA256 device seed)
- Nostr: kind 20000 + #g tag, nickname tag (n), filter helper
- iOS: LocationChannelManager (permissions, one-shot location), Info.plist string
- UI: toolbar # badge (#mesh or #<level>), sheet (irc style, full-row taps, settings link)
- VM: subscribe/send for active channel, clear timeline on switch, nickname cache
- Emotes: route public via Nostr/mesh without echo, local system confirmation, emojis restored
- Haptics: detect hugs/slaps for nickname#abcd and trigger on receiver
- Rendering: remove hashtag/mention formatting (plain monospaced)

Note: iOS-only; macOS unaffected.

* Lifecycle and persistence: resubscribe on foreground/relay connect, cap dedup set, persist mesh timeline.

- ChatViewModel: resubscribe geohash on app foreground and relay reconnect
- Add processed Nostr events cap (2k) with eviction
- Persist mesh public messages in meshTimeline; hydrate on switching to #mesh
- Local geochat messages use nostr: senderPeerID for classification
- Tests: fix JSON contains assertion for #g tag

* Fix Swift 6 concurrency warnings: remove closure-based NC observer, wrap relay reconnect resubscribe in Task @MainActor, resubscribe in appDidBecomeActive selector.

* Location Channels polish: live geohash refresh while sheet open; keep selection stable; toolbar shows #<geohash>; sheet labels show human level + #geohash.

* Add per-geohash in-memory timelines and cap private chats to 1337.

- ChatViewModel: persist geohash messages in geoTimelines[geohash] with cap; hydrate timeline on channel switch
- PrivateChatManager: trim per-peer chats to 1337 on send/receive
- Toolbar badge: prevent wrapping with lineLimit(1)/truncation

* Toolbar badge layout + brand color; Teleport custom geohash; Live refresh uses startUpdatingLocation with significant distance.

- Toolbar: right-justify geohash, head truncation, use brand green
- Sheet: add #custom geohash textfield + join; keep minimal IRClike style
- Manager: startUpdatingLocation()/stopUpdatingLocation() with distanceFilter=250 while sheet is open

* Location sheet live updates: reduce distanceFilter to 21m for more frequent geohash refreshes while open.

* Toolbar badge spacing/width; Sheet: rename to #geohash and button 'teleport'.

- Move # label closer to peer count and widen to avoid truncation
- Change custom field placeholder to '#geohash' and action button to 'teleport' with monospaced font

* Sheet polish: style 'teleport' button with subtle background, disable until valid; prefix '#' label and placeholder 'geohash'; center + style 'remove location permission' and hide separators for these rows.  Toolbar: adjust spacing/width for # label.

* Sheet UX: restrict custom geohash input to valid base32 (lowercase, max 12), reduce spacing so placeholder sits closer to '#', add divider under country row, style 'remove permission' and hide row separators as before. Toolbar: minor spacing/width already adjusted.

* Sheet behavior: show channel list even without permission; add green 'get location and my geohash' button; ensure only one separator between country and teleport by removing manual Divider and showing default row separator; refine teleport input filtering and spacing.

* Channel activity nudges: notify after 9 minutes inactivity only in background; triple-tap clear also clears persistent timelines.

- ChatViewModel: track last activity per channel; send local notification when new activity resumes while app in background (with small cooldown)
- CommandProcessor: /clear clears current public channel persistence via viewModel helper

* Fix compile: add activeChannelDisplayName() and clearCurrentPublicTimeline() helpers in ChatViewModel.

* Fix concurrent dictionary access in BLEService.broadcastPacket: snapshot shared collections under collectionsQueue to avoid CocoaDictionary iterator crashes.

* People: channel-aware list and counts

- Sidebar: NETWORK → PEOPLE; removed PEOPLE subheader/icon
- Toolbar: blue #mesh badge; green #<geohash> badge; count color by channel
- Geohash participants: track per-geohash unique senders with 5m decay; publish list
- Update on geohash send/receive; 30s prune timer; channel switch hooks

No changes to mesh peer UX; mesh list retained as-is.

* BLE: snapshot collections for thread-safe access; stopServices uses snapshot; safe characteristic snapshot in broadcast path

LocationChannelsSheet: rename button label to 'remove location access'

* Channel sheet: show current peer counts

- Mesh row shows connected mesh peers count
- Geohash rows show 5m-active participant counts via ViewModel
- Live-updates while sheet is open

* Channel sheet: pluralize counts as 'person/people' in titles

* Geohash sampling: subscribe to all available channels while sheet open

- ViewModel: add multi-channel sampling subscriptions and per-geohash participant updates
- Sheet: start sampling on appear, sync on list changes, stop on disappear

* Channel sheet: render counts '(N person/people)' in smaller font next to label

* Channel sheet: use square brackets for counts and adjust parsing; fix mesh title to '#mesh'

* Geohash DMs: implement send/receive via NIP-17 with per-geohash identity

- NostrEmbeddedBitChat: add no-recipient encoder for geohash DMs
- NostrTransport: add sendPrivateMessageGeohash(using provided identity)
- ChatViewModel:
  • startGeohashDM + mapping helpers
  • subscribe to per-geohash gift wraps; store DMs in conversations keyed by 'nostr_<prefix>'
  • route sendPrivateMessage() for 'nostr_' to Nostr geohash send; local echo and status
  • map pubkeys from geohash public events for DM initiation
  • resubscribe DM feed on reconnect and channel switch; unsubscribe on leave
- ContentView: long-press 'private message' starts geohash DM when sender is nostr

* Geohash DMs UX: tap participants to DM; support /msg nickname in geohash; DM notifications

- People (geohash) list: bold 'you', sort to top, tap to open DM
- ChatViewModel.getPeerIDForNickname resolves geohash names to nostr_ conv keys
- Geohash DM receive: send local notification when not viewing

* Geohash DMs polish: header title, star hidden, self-DM blocked, message icon, delivered/read ACKs

- Header shows '#<geohash>/@name#abcd' for geohash DMs; hide favorite star
- Geohash people row: add small message icon; prevent self tap
- Prevent sending geohash DM to self
- Send delivery/read ACKs on receive; handle delivered/read to update status

* Geohash DMs: hide encryption status icon in DM header

* BLE: fix data race in broadcast path

- Snapshot peripherals via Array(values) and filter outside sync
- Snapshot subscribedCentrals and centralToPeerID under collectionsQueue
- Mutate subscribedCentrals under collectionsQueue barriers in didSubscribe/unsubscribe

* LocationChannelsSheet: open fully by default (large detent only)

* BLE: remove unused centralMapSnapshot variable

* Geohash DMs: only notify on incoming PM when app is backgrounded; avoid foreground noise

* GeoDM: reliable delivered/read receipts, background-only notifications, and UI tweak

- Implement delivered + read receipts for geohash DMs; send READ on open\n- Handle relay OK acks for gift-wrap sends; resubscribe processes PM/DELIVERED/READ\n- Prevent mesh Noise handshakes for virtual geohash peers (nostr_*)\n- Notify GeoDMs only in background; suppress alerts for already-read msgs\n- Logging: promote key GeoDM receive logs; demote/remove verbose noise\n- UI: remove trailing envelope button from geohash People list

* Fix: remove duplicate variable declarations in AnnouncementPacket.decode()

---------

Co-authored-by: jack <jackjackbits@users.noreply.github.com>
2025-08-20 01:10:23 +02:00
2025-08-20 01:10:23 +02:00
2025-07-23 09:33:07 +02:00
2025-08-17 15:17:04 +02:00
2025-07-10 21:00:12 +05:30

icon_128x128@2x

bitchat

A decentralized peer-to-peer messaging app that works over Bluetooth mesh networks. No internet required, no servers, no phone numbers. It's the side-groupchat.

bitchat.free

📲 App Store

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 for identity and encryption. Public local chat (the main feature) has no security concerns.

License

This project is released into the public domain. See the LICENSE file for details.

Features

  • 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
  • IRC-Style Commands: Familiar /slap, /msg, /who style interface
  • Universal App: Native support for iOS and macOS
  • Emergency Wipe: Triple-tap to instantly clear all data
  • Performance Optimizations: LZ4 message compression, adaptive battery modes, and optimized networking

Technical Architecture

Binary Protocol

bitchat uses an efficient binary protocol optimized for Bluetooth LE:

  • Compact packet format with 1-byte type field
  • TTL-based message routing (max 7 hops)
  • Automatic fragmentation for large messages
  • Message deduplication via unique IDs

Mesh Networking

  • Each device acts as both client and peripheral
  • Automatic peer discovery and connection management
  • Adaptive duty cycling for battery optimization

For detailed protocol documentation, see the Technical Whitepaper.

Setup

  1. Install XcodeGen if you haven't already:

    brew install xcodegen
    
  2. Generate the Xcode project:

    cd bitchat
    xcodegen generate
    
  3. Open the generated project:

    open bitchat.xcodeproj
    

Option 2: Using Swift Package Manager

  1. Open the project in Xcode:

    cd bitchat
    open Package.swift
    
  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.

S
Description
bluetooth mesh chat, IRC vibes
Readme Unlicense
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