// lib/services/playback_service.dart
import 'package:media_kit/media_kit.dart';

// ============================================================
// PlaybackService - 播放引擎封装
// 职责：管理 Player 生命周期，不涉及业务逻辑
// ============================================================
class PlaybackService {
  static final PlaybackService _instance = PlaybackService._internal();
  factory PlaybackService() => _instance;
  PlaybackService._internal();

  Player? _player;
  bool _initialized = false;

  // ---------- Getter ----------
  Player get player {
    if (!_initialized) init();
    return _player!;
  }

  bool get isInitialized => _initialized;

  // ---------- 初始化 ----------
  void init() {
    if (_initialized) return;
    _player = Player();
    _initialized = true;

    // 可以在这里配置初始参数
    // _player.setVolume(1.0);
  }

  // ---------- 播放 ----------
  Future<void> play(String url, {Map<String, String>? headers}) async {
    if (!_initialized) init();

    final media = (headers != null && headers.isNotEmpty)
        ? Media(url, httpHeaders: headers)
        : Media(url);

    await _player!.open(media);
    await _player!.play();
  }

  // ---------- 控制 ----------
  Future<void> pause() async {
    if (_initialized && _player != null) {
      await _player!.pause();
    }
  }

  Future<void> resume() async {
    if (_initialized && _player != null) {
      await _player!.play();
    }
  }

  Future<void> stop() async {
    if (_initialized && _player != null) {
      await _player!.stop();
    }
  }

  Future<void> seek(Duration position) async {
    if (_initialized && _player != null) {
      await _player!.seek(position);
    }
  }

  void setVolume(double volume) {
    if (_initialized && _player != null) {
      _player!.setVolume(volume);
    }
  }

  // ---------- 释放 ----------
  void dispose() {
    if (_initialized && _player != null) {
      _player!.dispose();
      _player = null;
      _initialized = false;
    }
  }

  // ---------- 重新初始化（用于 Hot Restart 场景） ----------
  void reinitialize() {
    dispose();
    init();
  }
}