// lib/controllers/playback_controller.dart
import '../services/audio_service.dart';
import '../services/webdav_service.dart';
import '../database/song_database.dart';

class PlaybackController {
  static final PlaybackController _instance = PlaybackController._internal();
  factory PlaybackController() => _instance;
  PlaybackController._internal();

  final AudioService _audioService = AudioService();
  final SongDatabase _db = SongDatabase();

  // ════════════════════════════════════════════════════════════
  // 播放 WebDAV 目录中的歌曲（从点击歌曲开始）
  // ════════════════════════════════════════════════════════════
  Future<void> playFromWebDAV({
    required String directoryPath,
    required String clickedSongPath,
    required List<WebDAVItem> allItems,
  }) async {
    final musicFiles = allItems.where((item) => !item.isDirectory).toList();
    if (musicFiles.isEmpty) return;

    final clickedIndex =
        musicFiles.indexWhere((item) => item.path == clickedSongPath);
    if (clickedIndex == -1) {
      await _playSingleSong(clickedSongPath);
      return;
    }

    final queue = await _buildSongQueue(musicFiles);

    final playMode = _audioService.playMode;
    // ⭐ 修复：显式指定类型
    List<Song> finalQueue = List<Song>.from(queue);
    int startIndex = clickedIndex;

    if (playMode == PlayMode.shuffle) {
      final shuffled = List<Song>.from(queue)..shuffle();
      startIndex = shuffled.indexWhere((s) => s.id == clickedSongPath);
      if (startIndex == -1) startIndex = 0;
      finalQueue = shuffled;
    }

    _audioService.setQueue(finalQueue, startIndex: startIndex);
  }

  // ════════════════════════════════════════════════════════════
  // 播放整个目录（从第一首开始）
  // ════════════════════════════════════════════════════════════
  Future<void> playAllFromWebDAV({
    required String directoryPath,
    required List<WebDAVItem> allItems,
  }) async {
    final musicFiles = allItems.where((item) => !item.isDirectory).toList();
    if (musicFiles.isEmpty) return;

    final queue = await _buildSongQueue(musicFiles);

    final playMode = _audioService.playMode;
    // ⭐ 修复：显式指定类型
    List<Song> finalQueue = List<Song>.from(queue);
    if (playMode == PlayMode.shuffle) {
      finalQueue = List<Song>.from(queue)..shuffle();
    }

    _audioService.setQueue(finalQueue, startIndex: 0);
  }

  // ════════════════════════════════════════════════════════════
  // 播放单曲（fallback）
  // ════════════════════════════════════════════════════════════
  Future<void> _playSingleSong(String songPath) async {
    final url = WebDAVService.instance.getFileUrl(songPath);
    final dbSong = await _db.getSongByPath(songPath);
    final song = Song(
      id: songPath,
      title: dbSong?['title'] as String? ??
          songPath.split('/').last.replaceAll(RegExp(r'\.[^.]*$'), ''),
      artist: dbSong?['artist'] as String? ?? '未知艺术家',
      url: url,
    );
    _audioService.playSong(song);
  }

  // ════════════════════════════════════════════════════════════
  // 辅助方法：从音乐文件列表构建 Song 队列
  // ════════════════════════════════════════════════════════════
  Future<List<Song>> _buildSongQueue(List<WebDAVItem> musicFiles) async {
    final queue = <Song>[];
    for (final item in musicFiles) {
      final dbSong = await _db.getSongByPath(item.path);
      final url = WebDAVService.instance.getFileUrl(item.path);
      if (dbSong != null) {
        queue.add(Song(
          id: item.path,
          title: dbSong['title'] as String? ??
              item.name.replaceAll(RegExp(r'\.[^.]*$'), ''),
          artist: dbSong['artist'] as String? ?? '未知艺术家',
          url: url,
        ));
      } else {
        queue.add(Song(
          id: item.path,
          title: item.name.replaceAll(RegExp(r'\.[^.]*$'), ''),
          artist: '未知艺术家',
          url: url,
        ));
      }
    }
    return queue;
  }

  // ════════════════════════════════════════════════════════════
  // 播放控制（透传到 AudioService）
  // ════════════════════════════════════════════════════════════
  void next() {
    _audioService.next();
  }

  void previous() {
    _audioService.previous();
  }

  void togglePlayMode() {
    _audioService.togglePlayMode();
  }

  PlayMode get playMode => _audioService.playMode;
}