functional carplay experience in simulators

lib/carplay_bridge.dart

@@ -0,0 +1,77 @@
+import 'package:flutter/services.dart';
+
+import 'streaming_audio_business_object.dart';
+
+class CarPlayBridge {
+  CarPlayBridge({required StreamingAudioBusinessObject audio}) : _audio = audio;
+
+  static const MethodChannel _channel = MethodChannel(
+    'kryz_go_flutter/carplay/methods',
+  );
+
+  final StreamingAudioBusinessObject _audio;
+  bool _isStarted = false;
+
+  Future<void> start() async {
+    if (_isStarted) {
+      return;
+    }
+
+    _isStarted = true;
+    _channel.setMethodCallHandler(_handleNativeMethodCall);
+    _audio.addListener(_onAudioChanged);
+    await _pushSnapshotToNative();
+  }
+
+  Future<void> dispose() async {
+    if (!_isStarted) {
+      return;
+    }
+
+    _isStarted = false;
+    _audio.removeListener(_onAudioChanged);
+    _channel.setMethodCallHandler(null);
+  }
+
+  Map<String, dynamic> _snapshot() {
+    final String playbackStatus = switch (_audio.playbackStatus) {
+      StreamingPlaybackStatus.playing => 'playing',
+      StreamingPlaybackStatus.buffering => 'buffering',
+      StreamingPlaybackStatus.stopped => 'stopped',
+    };
+
+    return <String, dynamic>{
+      'playbackStatus': playbackStatus,
+      'isPlaying': _audio.isPlaying,
+      'isBuffering': _audio.isBuffering,
+      'isLive': true,
+      'seekable': false,
+      'title': _audio.currentTitle,
+      'subtitle': _audio.currentSubtitle,
+      'album': 'Live',
+    };
+  }
+
+  Future<dynamic> _handleNativeMethodCall(MethodCall call) async {
+    switch (call.method) {
+      case 'getStateSnapshot':
+        return _snapshot();
+      default:
+        throw MissingPluginException('Unknown CarPlay bridge method: ${call.method}');
+    }
+  }
+
+  void _onAudioChanged() {
+    _pushSnapshotToNative();
+  }
+
+  Future<void> _pushSnapshotToNative() async {
+    try {
+      await _channel.invokeMethod<void>('syncState', _snapshot());
+    } on MissingPluginException {
+      // CarPlay bridge only exists on iOS native builds.
+    } on PlatformException {
+      // Keep playback working even if native sync temporarily fails.
+    }
+  }
+}

lib/kryz_audio_handler.dart

@@ -126,6 +126,13 @@ class KryzAudioHandler extends BaseAudioHandler with SeekHandler {
     );
   }
 
+  @override
+  Future<void> pause() async {
+    // CarPlay and lock-screen transport may issue pause for live streams.
+    // Treat pause as stop to keep behavior consistent across platforms.
+    await stop();
+  }
+
   @override
   Future<void> seek(Duration position) async {
     // Live stream is intentionally non-seekable.

lib/main.dart

@@ -5,6 +5,7 @@ import 'package:flutter/foundation.dart';
 import 'package:flutter/services.dart';
 import 'package:timezone/data/latest.dart' as tz;
 import 'app_theme_business_object.dart';
+import 'carplay_bridge.dart';
 import 'casting_business_object.dart';
 import 'live_info_business_object.dart';
 import 'live_info_panel.dart';
@@ -35,16 +36,20 @@ class MyApp extends StatefulWidget {
 class _MyAppState extends State<MyApp> {
   final StreamingAudioBusinessObject _audio = StreamingAudioBusinessObject();
   final CastingBusinessObject _casting = CastingBusinessObject();
+  late final CarPlayBridge _carPlayBridge;
 
   @override
   void initState() {
     super.initState();
+    _carPlayBridge = CarPlayBridge(audio: _audio);
     unawaited(_audio.ensureInitialized());
+    unawaited(_carPlayBridge.start());
     _casting.initialize();
   }
 
   @override
   void dispose() {
+    unawaited(_carPlayBridge.dispose());
     _casting.dispose();
     _audio.dispose();
     super.dispose();