// lib/pages/webdav_file_list_page.dart
// ignore: unused_import
import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import '../services/webdav_service.dart';
import '../services/playback_service.dart';
import '../services/audio_service.dart';
import '../constants/ui_constants.dart';

class WebDAVFileListPage extends StatefulWidget {
  final String currentPath;

  const WebDAVFileListPage({super.key, this.currentPath = '/'});

  @override
  State<WebDAVFileListPage> createState() => _WebDAVFileListPageState();
}

class _WebDAVFileListPageState extends State<WebDAVFileListPage> {
  List<WebDAVItem> _items = [];
  bool _isLoading = true;
  String _errorMessage = '';
  String _currentPath = '/';

  // 安全解码
  String _safeDecode(String input) {
    try {
      return Uri.decodeComponent(input);
    } catch (_) {
      return input;
    }
  }

  @override
  void initState() {
    super.initState();
    _currentPath = widget.currentPath;
    _loadDirectory();
  }

  // ============================================================
  // 加载目录
  // ============================================================
  Future<void> _loadDirectory() async {
    setState(() {
      _isLoading = true;
      _errorMessage = '';
    });

    try {
      final items =
          await WebDAVService.instance.listDirectory(path: _currentPath);
      setState(() {
        _items = items;
        _isLoading = false;
      });
    } catch (e) {
      setState(() {
        _errorMessage = '加载失败: $e';
        _isLoading = false;
      });
    }
  }

  // ============================================================
  // 进入子目录
  // ============================================================
  void _enterDirectory(WebDAVItem dir) {
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (_) => WebDAVFileListPage(currentPath: dir.path),
      ),
    );
  }

  // ============================================================
  // ⭐ 核心：播放歌曲 + 自动构建队列
  // ============================================================
  void _playSong(WebDAVItem file) async {
    try {
      // 1. 获取当前目录所有音乐文件（过滤掉目录）
      final musicFiles = _items.where((item) => !item.isDirectory).toList();

      if (musicFiles.isEmpty) {
        if (mounted) {
          ScaffoldMessenger.of(context).showSnackBar(
            const SnackBar(
              content: Text('当前目录没有音乐文件'),
              backgroundColor: Colors.orange,
            ),
          );
        }
        return;
      }

      // 2. 获取认证头
      final headers = await WebDAVService.instance.getAuthHeaders();

      // 3. 构建播放队列（所有音乐文件）
      final queue = musicFiles.map((item) {
        final itemUrl = WebDAVService.instance.getFileUrl(item.path);
        return Song(
          id: item.path,
          title: item.name.replaceAll(RegExp(r'\.[^.]*$'), ''),
          artist: '未知艺术家',
          url: itemUrl,
        );
      }).toList();

      // 4. 找到当前点击歌曲在队列中的位置
      final startIndex = queue.indexWhere((s) => s.id == file.path);
      if (startIndex == -1) {
        // 极端情况：队列构建有问题，退化为单曲播放
        final url = WebDAVService.instance.getFileUrl(file.path);
        final song = Song(
          id: file.path,
          title: file.name.replaceAll(RegExp(r'\.[^.]*$'), ''),
          artist: '未知艺术家',
          url: url,
        );
        context.read<AudioService>().setQueue([song], startIndex: 0);
        await PlaybackService().play(url, headers: headers);
        return;
      }

      // 5. 设置队列并播放
      final audioService = context.read<AudioService>();
      audioService.setQueue(queue, startIndex: startIndex);

      // 6. 播放（AudioService 内部已经调用了 PlaybackService，但为了确保认证头传递）
      // 这里再显式调用一下，确保认证头正确
      final targetUrl = queue[startIndex].url!;
      await PlaybackService().play(targetUrl, headers: headers);

      // 7. 更新 AudioService 的播放状态（确保 UI 同步）
      // setQueue 已经调用了 _playCurrent()，所以这里不需要重复调用

      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text('正在播放: ${file.name}'),
            backgroundColor: const Color(0xFF4CAF50),
            duration: const Duration(seconds: 1),
          ),
        );
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text('播放失败: $e'),
            backgroundColor: Colors.red,
          ),
        );
      }
    }
  }

  // ============================================================
  // 全部播放（从第一首开始）
  // ============================================================
  void _playAll() async {
    try {
      final musicFiles = _items.where((item) => !item.isDirectory).toList();

      if (musicFiles.isEmpty) {
        if (mounted) {
          ScaffoldMessenger.of(context).showSnackBar(
            const SnackBar(
              content: Text('当前目录没有音乐文件'),
              backgroundColor: Colors.orange,
            ),
          );
        }
        return;
      }

      final headers = await WebDAVService.instance.getAuthHeaders();

      final queue = musicFiles.map((item) {
        final itemUrl = WebDAVService.instance.getFileUrl(item.path);
        return Song(
          id: item.path,
          title: item.name.replaceAll(RegExp(r'\.[^.]*$'), ''),
          artist: '未知艺术家',
          url: itemUrl,
        );
      }).toList();

      final audioService = context.read<AudioService>();
      audioService.setQueue(queue, startIndex: 0);

      final targetUrl = queue[0].url!;
      await PlaybackService().play(targetUrl, headers: headers);

      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text('开始播放全部 (${queue.length}首)'),
            backgroundColor: const Color(0xFF4CAF50),
            duration: const Duration(seconds: 1),
          ),
        );
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text('播放失败: $e'),
            backgroundColor: Colors.red,
          ),
        );
      }
    }
  }

  // ============================================================
  // 显示路径
  // ============================================================
  String _getDisplayPath() {
    if (_currentPath == '/' || _currentPath.isEmpty) return '根目录';

    final decoded = _safeDecode(_currentPath);
    final parts = decoded.split('/').where((s) => s.isNotEmpty).toList();

    if (parts.isEmpty) return '根目录';
    if (parts.length <= 2) return parts.join(' / ');
    return '... / ${parts.sublist(parts.length - 2).join(' / ')}';
  }

  // ============================================================
  // Build
  // ============================================================
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: const Color(0xFF0E1211),
      appBar: AppBar(
        title: Text(
          _getDisplayPath(),
          style: const TextStyle(fontSize: 16),
        ),
        backgroundColor: Colors.transparent,
        elevation: 0,
        foregroundColor: Colors.white,
        leading: IconButton(
          icon: const Icon(Icons.arrow_back_ios_new),
          onPressed: () => Navigator.pop(context),
        ),
        actions: [
          // 全部播放按钮
          IconButton(
            icon: const Icon(Icons.playlist_play),
            onPressed: _playAll,
            tooltip: '全部播放',
          ),
          IconButton(
            icon: const Icon(Icons.refresh),
            onPressed: _loadDirectory,
            tooltip: '刷新',
          ),
        ],
      ),
      body: _isLoading
          ? const Center(
              child: CircularProgressIndicator(
                color: Color(0xFFB8D4D0),
              ),
            )
          : _errorMessage.isNotEmpty
              ? Center(
                  child: Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    children: [
                      Icon(Icons.error_outline,
                          size: 48, color: Colors.grey[600]),
                      const SizedBox(height: 16),
                      Text(
                        _errorMessage,
                        style: TextStyle(color: Colors.grey[400]),
                        textAlign: TextAlign.center,
                      ),
                      const SizedBox(height: 16),
                      ElevatedButton(
                        onPressed: _loadDirectory,
                        style: ElevatedButton.styleFrom(
                          backgroundColor: const Color(0xFFB8D4D0),
                          foregroundColor: Colors.black87,
                        ),
                        child: const Text('重试'),
                      ),
                    ],
                  ),
                )
              : _items.isEmpty
                  ? Center(
                      child: Column(
                        mainAxisAlignment: MainAxisAlignment.center,
                        children: [
                          Icon(Icons.folder_open,
                              size: 48, color: Colors.grey[600]),
                          const SizedBox(height: 16),
                          Text(
                            '此目录为空',
                            style: TextStyle(color: Colors.grey[400]),
                          ),
                          const SizedBox(height: 8),
                          Text(
                            '支持格式: MP3, FLAC, M4A, APE, WAV, OPUS',
                            style: TextStyle(
                                color: Colors.grey[600], fontSize: 12),
                          ),
                        ],
                      ),
                    )
                  : ListView.builder(
                      padding: const EdgeInsets.only(
                        left: 16,
                        right: 16,
                        top: 8,
                        bottom: UIConstants.miniPlayerBottomSpace,
                      ),
                      itemCount: _items.length,
                      itemBuilder: (context, index) {
                        final item = _items[index];
                        return _buildListItem(item);
                      },
                    ),
    );
  }

  // ============================================================
  // 构建列表项
  // ============================================================
  Widget _buildListItem(WebDAVItem item) {
    final displayName = _safeDecode(item.name);

    if (item.isDirectory) {
      return ListTile(
        contentPadding: const EdgeInsets.symmetric(horizontal: 4, vertical: 2),
        leading: const Icon(
          Icons.folder_outlined,
          color: Color(0xFFB8D4D0),
          size: 32,
        ),
        title: Text(
          displayName,
          style: const TextStyle(
            fontSize: 16,
            fontWeight: FontWeight.w500,
            color: Colors.white,
          ),
          maxLines: 1,
          overflow: TextOverflow.ellipsis,
        ),
        subtitle: Text(
          '文件夹',
          style: TextStyle(
            fontSize: 12,
            color: Colors.grey[500],
          ),
        ),
        trailing: const Icon(
          Icons.chevron_right,
          color: Colors.grey,
        ),
        onTap: () => _enterDirectory(item),
      );
    } else {
      final sizeStr = item.size != null
          ? '${(item.size! / 1024 / 1024).toStringAsFixed(1)} MB'
          : '';
      return ListTile(
        contentPadding: const EdgeInsets.symmetric(horizontal: 4, vertical: 2),
        leading: const Icon(
          Icons.audiotrack,
          color: Color(0xFFB8D4D0),
          size: 28,
        ),
        title: Text(
          displayName,
          style: const TextStyle(
            fontSize: 16,
            fontWeight: FontWeight.w400,
            color: Colors.white,
          ),
          maxLines: 1,
          overflow: TextOverflow.ellipsis,
        ),
        subtitle: Text(
          sizeStr,
          style: TextStyle(
            fontSize: 12,
            color: Colors.grey[500],
          ),
        ),
        trailing: IconButton(
          icon: const Icon(Icons.play_arrow, color: Color(0xFFB8D4D0)),
          onPressed: () => _playSong(item),
        ),
        onTap: () => _playSong(item),
      );
    }
  }
}