// ============================================================
// 文件名: webdav_file_list_page.dart
// 功能: WebDAV 文件浏览页面，支持文件夹导航和音乐播放
// 调用方式: Navigator.push(context, MaterialPageRoute(builder: (_) => WebDAVFileListPage()))
// ============================================================

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';

class WebDAVFileListPage extends StatefulWidget {
  /// 当前浏览路径，默认为根目录 '/'
  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 = '/';

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

  // -------------------------------------------------------------
  // 加载当前目录内容
  // -------------------------------------------------------------
  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),
      ),
    );
  }

  // -------------------------------------------------------------
  // 播放音乐文件
  // -------------------------------------------------------------
  void _playSong(WebDAVItem file) async {
    try {
      final url = WebDAVService.instance.getFileUrl(file.path);
      await PlaybackService().play(url);

      final song = Song(
        id: file.path,
        title: file.name.replaceAll(RegExp(r'\.[^.]*$'), ''),
        artist: '未知艺术家',
        url: url,
      );
      context.read<AudioService>().playSong(song);

      // ✅ 移除 SnackBar，直接显示 MiniPlayer
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text('播放失败: $e'),
            backgroundColor: Colors.red,
          ),
        );
      }
    }
  }

  // -------------------------------------------------------------
  // 构建面包屑路径显示（只显示最后两级，避免过长）
  // -------------------------------------------------------------
  String _getDisplayPath() {
    if (_currentPath == '/') return '根目录';
    final parts = _currentPath.split('/').where((s) => s.isNotEmpty).toList();
    if (parts.length <= 2) return parts.join(' / ');
    return '... / ${parts.sublist(parts.length - 2).join(' / ')}';
  }

  @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: [
          IconButton(
            icon: const Icon(Icons.refresh),
            onPressed: _loadDirectory,
            tooltip: '刷新',
          ),
        ],
      ),
      body: _buildBody(),
    );
  }

  // -------------------------------------------------------------
  // 构建主体内容
  // -------------------------------------------------------------
  Widget _buildBody() {
    if (_isLoading) {
      return const Center(
        child: CircularProgressIndicator(
          color: Color(0xFFB8D4D0),
        ),
      );
    }

    if (_errorMessage.isNotEmpty) {
      return 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'),
            ),
          ],
        ),
      );
    }

    if (_items.isEmpty) {
      return 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),
            ),
          ],
        ),
      );
    }

    return ListView.builder(
      padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
      itemCount: _items.length,
      itemBuilder: (context, index) {
        final item = _items[index];
        return _buildListItem(item);
      },
    );
  }

  // -------------------------------------------------------------
  // 构建单个列表项（区分目录和文件）
  // -------------------------------------------------------------
  Widget _buildListItem(WebDAVItem item) {
    if (item.isDirectory) {
      // ---------- 目录项 ----------
      return ListTile(
        contentPadding: const EdgeInsets.symmetric(horizontal: 4, vertical: 2),
        leading: const Icon(
          Icons.folder_outlined,
          color: Color(0xFFB8D4D0),
          size: 32,
        ),
        title: Text(
          item.name,
          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 {
      // ---------- 音乐文件项 ----------
      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(
          item.name,
          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),
      );
    }
  }
}