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.
    }
  }
}