// lib/services/audio_player_handler.dart

import 'package:flutter/foundation.dart';
import 'package:audio_service/audio_service.dart' as audio_service;
import '../audio/player_controller.dart';
import '../audio/playback_state_manager.dart';
import '../services/audio_service.dart';

class AudioPlayerHandler extends audio_service.BaseAudioHandler {
  final PlayerController _player = PlayerController();
  final PlaybackStateManager _state = PlaybackStateManager();

  String? _currentId;
  String? _currentTitle;
  String? _currentArtist;

  AudioPlayerHandler() {
    // ---- 播放状态 ----
    _player.playingStream.listen((playing) {
      _state.updatePlaying(playing);
      _publishState();
    });

    // ---- 进度变化 ----
    _player.positionStream.listen((position) {
      _state.updatePosition(position);
      // ⭐ 0.18.19 版本：通过更新 PlaybackState 的 updateTime 来驱动进度刷新
      _publishStateOnly();
    });

    // ---- 时长变化 ----
    _player.durationStream.listen((duration) {
      _state.updateDuration(duration);
      if (_currentId != null && _currentTitle != null) {
        _updateMediaItem(
          id: _currentId!,
          title: _currentTitle!,
          artist: _currentArtist!,
          duration: duration,
        );
      }
      _publishState();
    });
  }

  // ---- 发布完整状态 ----
  void _publishState() {
    playbackState.add(_state.playbackState);
  }

  // ---- 0.18.19 版本：只更新时间戳，驱动系统刷新进度 ----
  void _publishStateOnly() {
    final current = playbackState.value;
    playbackState.add(audio_service.PlaybackState(
      controls: current.controls,
      processingState: current.processingState,
      playing: current.playing,
      androidCompactActionIndices: current.androidCompactActionIndices,
      updateTime: DateTime.now(), // ⭐ 关键：更新时间戳，系统会重新读取位置
    ));
  }

  // ---- 更新媒体信息 ----
  void _updateMediaItem({
    required String id,
    required String title,
    required String artist,
    Duration? duration,
  }) {
    _currentId = id;
    _currentTitle = title;
    _currentArtist = artist;

    debugPrint('📢 [handler] updateMediaItem: $title - $artist');

    mediaItem.add(audio_service.MediaItem(
      id: id,
      title: title,
      artist: artist,
      duration: duration ?? _player.duration,
    ));
  }

  // ---- 外部接口 ----
  void updateNotification({
    required String id,
    required String title,
    required String artist,
  }) {
    _updateMediaItem(id: id, title: title, artist: artist);
    _publishState();
  }

  // ---- 控制命令 ----
  @override
  Future<void> play() async {
    debugPrint('▶️ [handler] play() called');
    _player.play();
    _publishState();
  }

  @override
  Future<void> pause() async {
    debugPrint('⏸️ [handler] pause() called');
    _player.pause();
    _publishState();
  }

  @override
  Future<void> stop() async {
    debugPrint('⏹️ [handler] stop() called');
    _player.stop();
    _publishState();
  }

  @override
  Future<void> seek(Duration position) async {
    debugPrint('⏩ [handler] seek() called: $position');
    _player.seek(position);
    _publishStateOnly();
  }

  @override
  Future<void> skipToNext() async {
    debugPrint('⏭️ [handler] skipToNext() called');
    AudioService().next();
  }

  @override
  Future<void> skipToPrevious() async {
    debugPrint('⏮️ [handler] skipToPrevious() called');
    AudioService().previous();
  }

  @override
  Future<void> click(
      [audio_service.MediaButton button =
          audio_service.MediaButton.media]) async {
    debugPrint('🎯 [handler] click() called with button: ${button.name}');
    switch (button) {
      case audio_service.MediaButton.next:
        await skipToNext();
        break;
      case audio_service.MediaButton.previous:
        await skipToPrevious();
        break;
      case audio_service.MediaButton.media:
        if (_player.isPlaying) {
          await pause();
        } else {
          await play();
        }
        break;
      default:
        // 其他按钮 fallback
        if (_player.isPlaying) {
          await pause();
        } else {
          await play();
        }
    }
  }
}