// lib/pages/player_page.dart
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';

import '../base/base_state.dart';
import '../database/song_database.dart';
import '../services/audio_service.dart';

class PlayerPage extends StatefulWidget {
  final VoidCallback? onClose;
  final VoidCallback? onOpenPlaylist;

  const PlayerPage({
    super.key,
    this.onClose,
    this.onOpenPlaylist,
  });

  @override
  State<PlayerPage> createState() => _PlayerPageState();
}

class _PlayerPageState extends BaseState<PlayerPage> {
  double? _dragProgress;

  bool _isFavorite = false;
  String _album = '';
  String _folder = '';
  String _dbTitle = '';
  String _dbArtist = '';
  String? _metaSongId;

  /// 0 = 文件信息，1 = 播放主页，2 = 歌词
  final PageController _pageController = PageController(initialPage: 1);
  int _pageIndex = 1;

  @override
  void dispose() {
    _pageController.dispose();
    super.dispose();
  }

  String _formatDuration(Duration d) {
    if (d.inMilliseconds < 0) return '00:00';
    final minutes = d.inMinutes;
    final seconds = d.inSeconds % 60;
    return '${minutes.toString().padLeft(2, '0')}:${seconds.toString().padLeft(2, '0')}';
  }

  void _closePage() {
    if (widget.onClose != null) {
      widget.onClose!();
    } else {
      Navigator.pop(context);
    }
  }

  void _openPlaylist() {
    if (widget.onOpenPlaylist != null) {
      widget.onOpenPlaylist!();
    } else {
      Navigator.pushNamed(context, '/playlist');
    }
  }

  @override
  void initState() {
    super.initState();
    _syncStateWithRetry();
  }

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    WidgetsBinding.instance.addPostFrameCallback((_) {
      if (mounted) {
        context.read<AudioService>().syncPlayerStateNow();
      }
    });
  }

  void _syncStateWithRetry() {
    final service = context.read<AudioService>();
    service.syncPlayerStateNow();

    const delays = [200, 500, 800, 1200];
    for (final delay in delays) {
      Future.delayed(Duration(milliseconds: delay), () {
        if (mounted) {
          service.syncPlayerStateNow();
        }
      });
    }
  }

  /// 元数据（专辑、收藏状态）只在切歌时查一次
  Future<void> _loadMeta(Song song) async {
    if (_metaSongId == song.id) return;
    _metaSongId = song.id;

    final db = SongDatabase();
    String album = '';
    String dbTitle = '';
    String dbArtist = '';
    bool favorite = false;
    try {
      final row = await db.getSongByPath(song.id);
      album = (row?['album'] as String?)?.trim() ?? '';
      dbTitle = (row?['title'] as String?)?.trim() ?? '';
      dbArtist = (row?['artist'] as String?)?.trim() ?? '';
      favorite = await db.isFavorite(song.id);
    } catch (_) {
      // 元数据只是装饰，失败忽略
    }

    // 上级目录名，作为没有专辑信息时的补充
    String folder = '';
    final segments =
        song.id.split('/').where((s) => s.isNotEmpty).toList();
    if (segments.length >= 2) {
      try {
        folder = Uri.decodeComponent(segments[segments.length - 2]);
      } catch (_) {
        folder = segments[segments.length - 2];
      }
    }

    if (!mounted) return;
    setState(() {
      _album = album;
      _folder = folder;
      _dbTitle = dbTitle;
      _dbArtist = dbArtist;
      _isFavorite = favorite;
    });
  }

  Future<void> _toggleFavorite(Song song) async {
    try {
      await SongDatabase().toggleFavorite(song.id);
      final favorite = await SongDatabase().isFavorite(song.id);
      if (!mounted) return;
      setState(() => _isFavorite = favorite);
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('收藏失败: $e')),
        );
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    final service = context.watch<AudioService>();
    final song = service.currentSong;

    if (song == null) {
      return Scaffold(
        backgroundColor: const Color(0xFF0E1211),
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              const Text(
                '没有正在播放的歌曲',
                style: TextStyle(color: Colors.grey),
              ),
              const SizedBox(height: 16),
              ElevatedButton(
                onPressed: _closePage,
                style: ElevatedButton.styleFrom(
                  backgroundColor: const Color(0xFFB8D4D0),
                  foregroundColor: Colors.black87,
                ),
                child: const Text('返回'),
              ),
            ],
          ),
        ),
      );
    }

    _loadMeta(song);
    final isPlaying = service.isPlaying;

    return Scaffold(
      backgroundColor: const Color(0xFF0E1211),
      appBar: AppBar(
        backgroundColor: Colors.transparent,
        elevation: 0,
        leading: IconButton(
          icon: const Icon(Icons.keyboard_arrow_down, color: Colors.white70),
          onPressed: _closePage,
        ),
        centerTitle: true,
        title: _buildPageIndicator(),
        actions: [
          PopupMenuButton<String>(
            icon: const Icon(Icons.more_vert, color: Colors.white54),
            onSelected: (value) async {
              if (value == 'clear_cache') {
                await context.read<AudioService>().clearCurrentSongCache();
                if (mounted) {
                  ScaffoldMessenger.of(context).showSnackBar(
                    const SnackBar(
                      content: Text('缓存已清除，重新加载中...'),
                      backgroundColor: Colors.orange,
                    ),
                  );
                }
              } else if (value == 'mode') {
                context.read<AudioService>().togglePlayMode();
              } else if (value == 'playlist') {
                _openPlaylist();
              }
            },
            itemBuilder: (context) => [
              PopupMenuItem(
                value: 'mode',
                child: Row(
                  children: [
                    Icon(service.playModeIcon, color: const Color(0xFFB8D4D0)),
                    const SizedBox(width: 12),
                    const Text('切换播放模式'),
                  ],
                ),
              ),
              const PopupMenuItem(
                value: 'playlist',
                child: Row(
                  children: [
                    Icon(Icons.queue_music, color: Color(0xFFB8D4D0)),
                    SizedBox(width: 12),
                    Text('播放队列'),
                  ],
                ),
              ),
              const PopupMenuItem(
                value: 'clear_cache',
                child: Row(
                  children: [
                    Icon(Icons.cleaning_services, color: Colors.redAccent),
                    SizedBox(width: 12),
                    Text('清除缓存'),
                  ],
                ),
              ),
            ],
          ),
        ],
      ),
      body: SafeArea(
        top: false,
        child: PageView(
          controller: _pageController,
          onPageChanged: (index) => setState(() => _pageIndex = index),
          children: [
            _buildInfoPage(song),
            _buildMainPage(service, song, isPlaying),
            _buildLyricsPage(song),
          ],
        ),
      ),
    );
  }

  /// 顶部指示器：当前页对应"长条"，另外两页是小点。
  /// 主页=中间长条，信息页=左长条，歌词页=右长条。
  Widget _buildPageIndicator() {
    Widget segment(int index) {
      final active = _pageIndex == index;
      return GestureDetector(
        onTap: () => _pageController.animateToPage(
          index,
          duration: const Duration(milliseconds: 280),
          curve: Curves.easeOutCubic,
        ),
        behavior: HitTestBehavior.opaque,
        child: Padding(
          padding: const EdgeInsets.symmetric(vertical: 10, horizontal: 2),
          child: AnimatedContainer(
            duration: const Duration(milliseconds: 220),
            curve: Curves.easeOutCubic,
            width: active ? 30 : 7,
            height: 7,
            decoration: BoxDecoration(
              color: active ? Colors.white : Colors.white24,
              borderRadius: BorderRadius.circular(4),
            ),
          ),
        ),
      );
    }

    return Row(
      mainAxisSize: MainAxisSize.min,
      children: [
        segment(0),
        const SizedBox(width: 6),
        segment(1),
        const SizedBox(width: 6),
        segment(2),
      ],
    );
  }

  Widget _buildMainPage(AudioService service, Song song, bool isPlaying) {
    return Padding(
      // 顶部留 16：与 AppBar/指示器拉开距离，避免封面贴着顶部
      padding: const EdgeInsets.fromLTRB(24, 24, 24, 0),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          // ---- 封面 ----
          AspectRatio(
            aspectRatio: 1,
            child: ClipRRect(
              borderRadius: BorderRadius.circular(24),
              child: song.artwork != null
                  ? Image.memory(
                      song.artwork!,
                      fit: BoxFit.cover,
                      gaplessPlayback: true,
                    )
                  : Container(
                      color: const Color(0xFF2A3332),
                      child: const Icon(
                        Icons.music_note,
                        size: 72,
                        color: Colors.white24,
                      ),
                    ),
            ),
          ),
          const SizedBox(height: 28),

          // ---- 标题 / 艺术家（收藏心在标题右侧）----
          Row(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Expanded(
                child: Text(
                  song.title,
                  style: const TextStyle(
                    fontSize: 24,
                    fontWeight: FontWeight.w600,
                    color: Colors.white,
                    height: 1.25,
                  ),
                  maxLines: 2,
                  overflow: TextOverflow.ellipsis,
                ),
              ),
              const SizedBox(width: 8),
              IconButton(
                onPressed: () => _toggleFavorite(song),
                tooltip: '收藏',
                icon: Icon(
                  _isFavorite ? Icons.favorite : Icons.favorite_border,
                  color: _isFavorite
                      ? const Color(0xFFE05C5C)
                      : Colors.white54,
                  size: 26,
                ),
              ),
            ],
          ),
          const SizedBox(height: 10),
          Text(
            song.artist,
            style: TextStyle(fontSize: 16, color: Colors.grey[300]),
            maxLines: 1,
            overflow: TextOverflow.ellipsis,
          ),

          // ---- 信息区（专辑 / 目录）----
          if (_album.isNotEmpty || _folder.isNotEmpty) ...[
            const SizedBox(height: 10),
            if (_album.isNotEmpty)
              Text(
                _album,
                style: TextStyle(
                  fontSize: 12,
                  color: Colors.grey[500],
                  height: 1.5,
                ),
                maxLines: 2,
                overflow: TextOverflow.ellipsis,
              ),
            if (_folder.isNotEmpty)
              Text(
                '($_folder)',
                style: TextStyle(
                  fontSize: 12,
                  color: Colors.grey[600],
                  height: 1.5,
                ),
                maxLines: 1,
                overflow: TextOverflow.ellipsis,
              ),
          ],

          const Spacer(),

          // ---- 进度 ----
          _buildProgressSection(service),
          const SizedBox(height: 18),

          // ---- 控制 ----
          _buildControlButtons(service, song, isPlaying),
          // 底部多留 50px：控制行整体上移
          const SizedBox(height: 45),
        ],
      ),
    );
  }

  /// 左页：文件信息
  Widget _buildInfoPage(Song song) {
    final rawName = song.id.split('/').last;
    String fileName = rawName;
    try {
      fileName = Uri.decodeComponent(rawName);
    } catch (_) {}

    final dot = fileName.lastIndexOf('.');
    final format =
        dot > 0 ? fileName.substring(dot + 1).toUpperCase() : '未知';

    String decodedPath = song.id;
    try {
      decodedPath = Uri.decodeComponent(song.id);
    } catch (_) {}

    final effectiveArtist = _dbArtist.isNotEmpty
        ? _dbArtist
        : (song.artist.isEmpty ? '未知' : song.artist);
    final effectiveTitle = _dbTitle.isNotEmpty ? _dbTitle : song.title;

    final rows = <MapEntry<String, String>>[
      MapEntry('标题', effectiveTitle),
      MapEntry('歌手', effectiveArtist),
      MapEntry('专辑', _album.isEmpty ? '未知' : _album),
      MapEntry('文件夹', _folder.isEmpty ? '根目录' : _folder),
      MapEntry('文件名', fileName),
      MapEntry('格式', format),
      MapEntry('路径', decodedPath),
    ];

    return SingleChildScrollView(
      padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 8),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          const Text(
            '文件信息',
            style: TextStyle(
              fontSize: 18,
              fontWeight: FontWeight.w600,
              color: Colors.white,
            ),
          ),
          const SizedBox(height: 20),
          for (final row in rows) ...[
            Text(
              row.key,
              style: TextStyle(fontSize: 12, color: Colors.grey[600]),
            ),
            const SizedBox(height: 4),
            Text(
              row.value,
              style: const TextStyle(
                fontSize: 14,
                color: Colors.white,
                height: 1.4,
              ),
            ),
            const SizedBox(height: 18),
          ],
        ],
      ),
    );
  }

  /// 右页：歌词（占位）
  Widget _buildLyricsPage(Song song) {
    return Center(
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          Icon(Icons.lyrics_outlined, size: 44, color: Colors.grey[700]),
          const SizedBox(height: 14),
          Text(
            '暂无歌词',
            style: TextStyle(fontSize: 14, color: Colors.grey[600]),
          ),
          const SizedBox(height: 6),
          Text(
            song.title,
            style: TextStyle(fontSize: 12, color: Colors.grey[700]),
            maxLines: 1,
            overflow: TextOverflow.ellipsis,
          ),
        ],
      ),
    );
  }

  Widget _buildProgressSection(AudioService service) {
    return ValueListenableBuilder(
      valueListenable: service.positionNotifier,
      builder: (context, position, _) {
        return ValueListenableBuilder(
          valueListenable: service.durationNotifier,
          builder: (context, duration, _) {
            if (duration.inMilliseconds == 0) {
              return const Padding(
                padding: EdgeInsets.symmetric(vertical: 8),
                child: LinearProgressIndicator(
                  color: Color(0xFFB8D4D0),
                  backgroundColor: Color(0xFF2A3332),
                ),
              );
            }

            final progress = position.inMilliseconds / duration.inMilliseconds;
            final bufferProgress = (service
                        .bufferedNotifier.value.inMilliseconds /
                    duration.inMilliseconds)
                .clamp(0.0, 1.0);
            final displayProgress = _dragProgress ?? progress;

            return Row(
              children: [
                Text(
                  _formatDuration(
                    _dragProgress != null
                        ? Duration(
                            milliseconds:
                                (_dragProgress! * duration.inMilliseconds)
                                    .round(),
                          )
                        : position,
                  ),
                  style: TextStyle(fontSize: 12, color: Colors.grey[500]),
                ),
                const SizedBox(width: 10),
                Expanded(
                  child: SizedBox(
                    height: 24,
                    child: LayoutBuilder(
                      builder: (context, constraints) {
                        final width = constraints.maxWidth;
                        return Stack(
                          alignment: Alignment.centerLeft,
                          children: [
                            // 背景轨道
                            Positioned(
                              left: 0,
                              right: 0,
                              top: 10.5,
                              child: Container(
                                height: 3,
                                decoration: BoxDecoration(
                                  color: Colors.grey[800],
                                  borderRadius: BorderRadius.circular(2),
                                ),
                              ),
                            ),
                            // 已缓冲
                            Positioned(
                              left: 0,
                              top: 10.5,
                              child: Container(
                                width: width * bufferProgress.clamp(0.0, 1.0),
                                height: 3,
                                decoration: BoxDecoration(
                                  color: const Color(0xFF4A7A7A),
                                  borderRadius: BorderRadius.circular(2),
                                ),
                              ),
                            ),
                            // 已播放
                            Positioned(
                              left: 0,
                              top: 10.5,
                              child: Container(
                                width:
                                    width * displayProgress.clamp(0.0, 1.0),
                                height: 3,
                                decoration: BoxDecoration(
                                  color: const Color(0xFFB8D4D0),
                                  borderRadius: BorderRadius.circular(2),
                                ),
                              ),
                            ),
                            Positioned.fill(
                              child: SliderTheme(
                                data: SliderTheme.of(context).copyWith(
                                  trackHeight: 0,
                                  activeTrackColor: Colors.transparent,
                                  inactiveTrackColor: Colors.transparent,
                                  thumbColor: Colors.transparent,
                                  overlayColor: Colors.transparent,
                                  thumbShape: const RoundSliderThumbShape(
                                    enabledThumbRadius: 0,
                                  ),
                                ),
                                child: Slider(
                                  value: displayProgress.clamp(0.0, 1.0),
                                  min: 0.0,
                                  max: 1.0,
                                  onChanged: (value) {
                                    setState(() => _dragProgress = value);
                                  },
                                  onChangeEnd: (value) {
                                    final newPosition = Duration(
                                      milliseconds:
                                          (value * duration.inMilliseconds)
                                              .round(),
                                    );
                                    service.seekTo(newPosition);
                                    setState(() => _dragProgress = null);
                                  },
                                ),
                              ),
                            ),
                          ],
                        );
                      },
                    ),
                  ),
                ),
                const SizedBox(width: 10),
                Text(
                  _formatDuration(duration),
                  style: TextStyle(fontSize: 12, color: Colors.grey[500]),
                ),
              ],
            );
          },
        );
      },
    );
  }

  Widget _buildControlButtons(
      AudioService service, Song song, bool isPlaying) {
    return Row(
      mainAxisAlignment: MainAxisAlignment.spaceBetween,
      children: [
        IconButton(
          onPressed: service.hasQueue ? service.previous : null,
          icon: const Icon(Icons.skip_previous_rounded, size: 34),
          color: service.hasQueue ? Colors.white70 : Colors.grey[700],
        ),
        Container(
          width: 68,
          height: 68,
          decoration: const BoxDecoration(
            color: Color(0xFFB8D4D0),
            shape: BoxShape.circle,
          ),
          child: IconButton(
            icon: Icon(
              isPlaying ? Icons.pause_rounded : Icons.play_arrow_rounded,
              color: Colors.black87,
              size: 36,
            ),
            padding: EdgeInsets.zero,
            onPressed: service.togglePlay,
          ),
        ),
        IconButton(
          onPressed: service.hasQueue ? service.next : null,
          icon: const Icon(Icons.skip_next_rounded, size: 34),
          color: service.hasQueue ? Colors.white70 : Colors.grey[700],
        ),
        IconButton(
          onPressed: service.togglePlayMode,
          icon: Icon(
            service.playModeIcon,
            color: const Color(0xFFB8D4D0),
            size: 26,
          ),
          tooltip: '播放模式',
        ),
        IconButton(
          onPressed: _openPlaylist,
          icon: const Icon(
            Icons.queue_music_rounded,
            color: Color(0xFFB8D4D0),
            size: 26,
          ),
          tooltip: '播放队列',
        ),
      ],
    );
  }
}