// lib/controllers/playback_controller.dart
import 'package:flutter/foundation.dart'; // ⭐ 添加
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();

  // ════════════════════════════════════════════════════════════
  // 从 WebDAV 目录播放（点击歌曲）
  // ════════════════════════════════════════════════════════════
  Future<void> playFromWebDAV({
    required String directoryPath,
    required String clickedSongPath,
    required List<WebDAVItem> allItems,
  }) async {
    // 1. 过滤出所有音乐文件（去掉目录）
    final musicFiles = allItems.where((item) => !item.isDirectory).toList()
      ..sort((a, b) => a.name.toLowerCase().compareTo(b.name.toLowerCase()));

    if (musicFiles.isEmpty) return;

    // 2. 调试信息
    debugPrint('🎯 [PlaybackController] musicFiles:');
    for (int i = 0; i < musicFiles.length; i++) {
      debugPrint('  $i: ${musicFiles[i].path}');
    }
    debugPrint('🎯 [PlaybackController] clickedSongPath: $clickedSongPath');

    // 3. 找到点击歌曲在音乐文件列表中的位置
    final clickedIndex =
        musicFiles.indexWhere((item) => item.path == clickedSongPath);
    debugPrint('🎯 [PlaybackController] clickedIndex: $clickedIndex');

    if (clickedIndex == -1) {
      debugPrint(
          '⚠️ [PlaybackController] clicked song not found, fallback to single play');
      await _playSingleSong(clickedSongPath);
      return;
    }

    // 4. 构建 Song 队列
    final queue = await _buildSongQueue(musicFiles);

    // 5. 应用播放模式
    final playMode = _audioService.playMode;
    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;
    }

    debugPrint(
        '🎯 [PlaybackController] finalQueue length: ${finalQueue.length}, startIndex: $startIndex');

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

  // ════════════════════════════════════════════════════════════
  // 从 WebDAV 目录播放（全部播放）
  // ════════════════════════════════════════════════════════════
  Future<void> playAllFromWebDAV({
    required String directoryPath,
    required List<WebDAVItem> allItems,
  }) async {
    final musicFiles = allItems.where((item) => !item.isDirectory).toList()
      ..sort((a, b) => a.name.toLowerCase().compareTo(b.name.toLowerCase()));

    if (musicFiles.isEmpty) return;

    final queue = await _buildSongQueue(musicFiles);

    final playMode = _audioService.playMode;
    List<Song> finalQueue = List<Song>.from(queue);
    if (playMode == PlayMode.shuffle) {
      finalQueue = List<Song>.from(queue)..shuffle();
    }

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

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

  // ════════════════════════════════════════════════════════════
  // 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
  // ════════════════════════════════════════════════════════════
  void next() => _audioService.next();
  void previous() => _audioService.previous();
  void togglePlayMode() => _audioService.togglePlayMode();
  PlayMode get playMode => _audioService.playMode;
}