feat: add Codec2 voice messages over LoRa mesh (iOS/macOS only)

Push-to-talk voice messaging using the Codec2 ultra-low-bitrate speech codec, transmitted as V: prefixed packets over the existing MeshCore LoRa mesh pipeline. Voice recording UI (long-press send button or + menu) is gated behind Platform.isIOS || Platform.isMacOS since the `record` package only supports microphone capture on those platforms in this build. Key changes: - VoiceRecorderService: streams 8kHz mono PCM chunks via `record` package - VoicePlayerService: decodes Codec2 bytes to WAV and plays via audioplayers - VoiceCodecService: async Codec2 encode/decode in background isolates - VoiceProvider: reassembles multi-packet sessions, drives playback - VoiceMessageBubble: shows packet progress, play/stop controls - MessagesProvider: detects V: prefix, routes to VoiceProvider - MessagesTab: PTT long-press gesture + recording indicator (iOS/macOS) - Message model: isVoice + voiceId fields for session tracking - Auto-selects codec mode from radio bandwidth (700C/1200/1300 bps) - codec2_flutter + meshcore_client switched from path to git deps
2026-08-11 16:30:28 +00:00 · 2026-02-28 19:19:18 +01:00
parent 3e5b2ac0de
commit f96d8022ac
27 changed files with 1509 additions and 81 deletions
--- a/lib/services/voice_player_service.dart
+++ b/lib/services/voice_player_service.dart
@@ -0,0 +1,98 @@
+import 'dart:io';
+import 'dart:typed_data';
+import 'package:audioplayers/audioplayers.dart';
+import 'package:flutter/foundation.dart';
+import 'package:path_provider/path_provider.dart';
+
+/// Plays decoded 8000 Hz / 16-bit mono PCM samples by writing a WAV file
+/// to the system temp directory and using [AudioPlayer].
+class VoicePlayerService {
+  final AudioPlayer _player = AudioPlayer();
+  bool _isPlaying = false;
+
+  bool get isPlaying => _isPlaying;
+
+  VoicePlayerService() {
+    _player.onPlayerStateChanged.listen((state) {
+      debugPrint('🔊 [VoicePlayer] state → $state');
+      _isPlaying = state == PlayerState.playing;
+    });
+    _player.onLog.listen((msg) => debugPrint('🔊 [VoicePlayer] log: $msg'));
+  }
+
+  /// Play [pcmSamples] (Int16, 8000 Hz, mono).
+  Future<void> play(Int16List pcmSamples) async {
+    debugPrint('🔊 [VoicePlayer] play() called, ${pcmSamples.length} samples');
+    if (_isPlaying) await stop();
+
+    final wavBytes = _buildWav(pcmSamples, sampleRate: 8000);
+    final tmpDir = await getTemporaryDirectory();
+    final file = File('${tmpDir.path}/vc_voice.wav');
+    await file.writeAsBytes(wavBytes);
+    debugPrint('🔊 [VoicePlayer] WAV written: ${wavBytes.length} bytes → ${file.path}');
+
+    try {
+      _isPlaying = true;
+      await _player.play(DeviceFileSource(file.path));
+      debugPrint('🔊 [VoicePlayer] play() returned (audio playing)');
+    } catch (e, st) {
+      debugPrint('❌ [VoicePlayer] play() error: $e\n$st');
+      _isPlaying = false;
+    }
+  }
+
+  Future<void> stop() async {
+    debugPrint('🔊 [VoicePlayer] stop()');
+    await _player.stop();
+    _isPlaying = false;
+  }
+
+  void dispose() {
+    _player.dispose();
+  }
+
+  // ── WAV file builder ─────────────────────────────────────────────────────
+
+  /// Constructs a minimal WAV (RIFF/PCM) file from Int16 mono samples.
+  static Uint8List _buildWav(Int16List samples, {required int sampleRate}) {
+    const int numChannels  = 1;
+    const int bitsPerSample = 16;
+    const int audioFormat  = 1; // PCM
+
+    final dataSize   = samples.length * 2; // 2 bytes per Int16 sample
+    final byteRate   = sampleRate * numChannels * bitsPerSample ~/ 8;
+    final blockAlign = numChannels * bitsPerSample ~/ 8;
+    final totalSize  = 36 + dataSize;
+
+    final buf = ByteData(44 + dataSize);
+    var offset = 0;
+
+    void writeStr(String s) {
+      for (final c in s.codeUnits) { buf.setUint8(offset++, c); }
+    }
+    void writeU32(int v) { buf.setUint32(offset, v, Endian.little); offset += 4; }
+    void writeU16(int v) { buf.setUint16(offset, v, Endian.little); offset += 2; }
+
+    writeStr('RIFF');
+    writeU32(totalSize);
+    writeStr('WAVE');
+    writeStr('fmt ');
+    writeU32(16);           // subchunk1 size
+    writeU16(audioFormat);  // 1 = PCM
+    writeU16(numChannels);
+    writeU32(sampleRate);
+    writeU32(byteRate);
+    writeU16(blockAlign);
+    writeU16(bitsPerSample);
+    writeStr('data');
+    writeU32(dataSize);
+
+    // PCM sample data (little-endian Int16)
+    for (final s in samples) {
+      buf.setInt16(offset, s, Endian.little);
+      offset += 2;
+    }
+
+    return buf.buffer.asUint8List();
+  }
+}