// lib/pages/settings_page.dart
import 'dart:io';

import 'package:android_intent_plus/android_intent.dart';
import 'package:android_intent_plus/flag.dart';
import 'package:flutter/material.dart';
import 'package:path_provider/path_provider.dart';

import '../database/song_database.dart';
import '../services/audio_service.dart';
import '../services/webdav_service.dart';
import '../utils/file_provider_utils.dart';

/// 与 pubspec.yaml 的 version 保持同步（发版时一起改）
const String kAppVersion = '1.1.0-dev.1';
const int kAppBuild = 2;

class SettingsPage extends StatefulWidget {
  const SettingsPage({super.key});

  @override
  State<SettingsPage> createState() => _SettingsPageState();
}

class _SettingsPageState extends State<SettingsPage> {
  bool _loading = true;

  int _songRows = 0;
  int _metadataRows = 0;
  int _favoriteRows = 0;
  int _artworkCount = 0;
  int _artworkBytes = 0;
  int _tempCount = 0;
  int _tempBytes = 0;

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

  Future<void> _loadStats() async {
    setState(() => _loading = true);
    try {
      final db = await SongDatabase().database;
      final songRows =
          (await db.rawQuery('SELECT COUNT(*) AS c FROM songs')).first['c'];
      final metaRows = (await db.rawQuery(
              'SELECT COUNT(*) AS c FROM metadata_cache'))
          .first['c'];
      final favRows =
          (await db.rawQuery('SELECT COUNT(*) AS c FROM favorites')).first['c'];

      var artworkCount = 0, artworkBytes = 0;
      final docs = await getApplicationDocumentsDirectory();
      final artDir = Directory('${docs.path}/artworks');
      if (await artDir.exists()) {
        await for (final entity in artDir.list()) {
          if (entity is File) {
            artworkCount++;
            artworkBytes += await entity.length();
          }
        }
      }

      var tempCount = 0, tempBytes = 0;
      final tmp = await getTemporaryDirectory();
      if (await tmp.exists()) {
        await for (final entity in tmp.list()) {
          if (entity is File &&
              entity.path.contains('/metadata_') &&
              entity.path.endsWith('.part')) {
            tempCount++;
            tempBytes += await entity.length();
          }
        }
      }

      if (!mounted) return;
      setState(() {
        _songRows = songRows as int? ?? 0;
        _metadataRows = metaRows as int? ?? 0;
        _favoriteRows = favRows as int? ?? 0;
        _artworkCount = artworkCount;
        _artworkBytes = artworkBytes;
        _tempCount = tempCount;
        _tempBytes = tempBytes;
        _loading = false;
      });
    } catch (e) {
      debugPrint('⚠️ [Settings] 统计失败: $e');
      if (mounted) setState(() => _loading = false);
    }
  }

  Future<void> _clearMetadataCache() async {
    final confirmed = await showDialog<bool>(
      context: context,
      builder: (context) => AlertDialog(
        backgroundColor: const Color(0xFF1A1F1E),
        title: const Text('清理元数据缓存', style: TextStyle(color: Colors.white)),
        content: const Text(
          '会删除歌曲标签缓存和封面文件，歌单与收藏不受影响。\n下次播放时重新抓取。',
          style: TextStyle(color: Colors.grey),
        ),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(context, false),
            child: const Text('取消'),
          ),
          TextButton(
            onPressed: () => Navigator.pop(context, true),
            child: const Text('清理', style: TextStyle(color: Colors.redAccent)),
          ),
        ],
      ),
    );
    if (confirmed != true) return;

    try {
      final db = await SongDatabase().database;
      await db.delete('songs');
      await db.delete('metadata_cache');

      final docs = await getApplicationDocumentsDirectory();
      final artDir = Directory('${docs.path}/artworks');
      if (await artDir.exists()) {
        await artDir.delete(recursive: true);
      }

      final tmp = await getTemporaryDirectory();
      if (await tmp.exists()) {
        await for (final entity in tmp.list()) {
          if (entity is File &&
              entity.path.contains('/metadata_') &&
              entity.path.endsWith('.part')) {
            await entity.delete();
          }
        }
      }

      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('元数据缓存已清理')),
        );
      }
      await _loadStats();
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context)
            .showSnackBar(SnackBar(content: Text('清理失败: $e')));
      }
    }
  }

  Future<void> _exportDiagnostics() async {
    try {
      final now = DateTime.now();
      final docs = await getApplicationDocumentsDirectory();
      final file =
          File('${docs.path}/diagnostics-${now.millisecondsSinceEpoch}.txt');

      final song = AudioService().currentSong;
      final buffer = StringBuffer()
        ..writeln('清听 诊断信息')
        ..writeln('时间: ${now.toIso8601String()}')
        ..writeln('版本: $kAppVersion ($kAppBuild)')
        ..writeln('平台: ${Platform.operatingSystem} ${Platform.operatingSystemVersion}')
        ..writeln()
        ..writeln('[连接]')
        ..writeln('baseUrl: ${WebDAVService.instance.baseUrl ?? '(未配置)'}')
        ..writeln('username: ${WebDAVService.instance.username ?? '(未配置)'}')
        ..writeln('connected: ${WebDAVService.instance.isConnected}')
        ..writeln()
        ..writeln('[数据]')
        ..writeln('songs: $_songRows')
        ..writeln('metadata_cache: $_metadataRows')
        ..writeln('favorites: $_favoriteRows')
        ..writeln('artwork 文件: $_artworkCount 个 / ${_formatBytes(_artworkBytes)}')
        ..writeln('临时探测文件: $_tempCount 个 / ${_formatBytes(_tempBytes)}')
        ..writeln()
        ..writeln('[当前播放]')
        ..writeln('song: ${song?.title ?? '(无)'} - ${song?.artist ?? ''}')
        ..writeln('path: ${song?.id ?? ''}')
        ..writeln('position: ${AudioService().position}')
        ..writeln('duration: ${AudioService().duration}')
        ..writeln('lastError: ${AudioService().lastPlaybackError ?? '(无)'}');

      await file.writeAsString(buffer.toString());
      if (!mounted) return;

      final uri = await FileProviderUtils.getContentUri(file);
      if (uri != null) {
        try {
          final intent = AndroidIntent(
            action: 'android.intent.action.SEND',
            type: 'text/plain',
            arguments: {
              'android.intent.extra.STREAM': uri.toString(),
              'android.intent.extra.SUBJECT': '清听诊断信息',
            },
            flags: const [Flag.FLAG_GRANT_READ_URI_PERMISSION],
          );
          await intent.launch();
          return;
        } catch (e) {
          debugPrint('⚠️ [Settings] 分享失败: $e');
        }
      }

      if (mounted) {
        showDialog<void>(
          context: context,
          builder: (context) => AlertDialog(
            backgroundColor: const Color(0xFF1A1F1E),
            title: const Text('诊断信息已导出', style: TextStyle(color: Colors.white)),
            content: SelectableText(
              file.path,
              style: const TextStyle(color: Colors.grey, fontSize: 12),
            ),
            actions: [
              TextButton(
                onPressed: () => Navigator.pop(context),
                child: const Text('好'),
              ),
            ],
          ),
        );
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context)
            .showSnackBar(SnackBar(content: Text('导出失败: $e')));
      }
    }
  }

  Future<void> _testConnection() async {
    try {
      await WebDAVService.instance.listDirectory(path: '/');
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('连接正常')),
        );
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('连接失败: $e')),
        );
      }
    }
  }

  Future<void> _logout() async {
    await WebDAVService.instance.clearCredentials();
    if (mounted) {
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(content: Text('已退出登录，下次进入会要求重新配置')),
      );
    }
  }

  String _formatBytes(int bytes) {
    if (bytes < 1024) return '$bytes B';
    if (bytes < 1024 * 1024) return '${(bytes / 1024).toStringAsFixed(1)} KB';
    return '${(bytes / 1024 / 1024).toStringAsFixed(1)} MB';
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: const Color(0xFF0E1211),
      appBar: AppBar(
        backgroundColor: Colors.transparent,
        elevation: 0,
        title: const Text('设置'),
      ),
      body: _loading
          ? const Center(child: CircularProgressIndicator())
          : ListView(
              padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
              children: [
                _sectionTitle('缓存'),
                ListTile(
                  leading: const Icon(Icons.cleaning_services_outlined,
                      color: Color(0xFF7C9A9E)),
                  title: const Text('元数据缓存'),
                  subtitle: Text(
                    '标签 $_songRows 首 · 封面 $_artworkCount 张 '
                    '(${_formatBytes(_artworkBytes)}) · 临时文件 ${_formatBytes(_tempBytes)}',
                    style: const TextStyle(fontSize: 12),
                  ),
                  trailing: const Icon(Icons.chevron_right, color: Colors.grey),
                  onTap: _clearMetadataCache,
                ),
                _sectionTitle('诊断'),
                ListTile(
                  leading: const Icon(Icons.bug_report_outlined,
                      color: Color(0xFF7C9A9E)),
                  title: const Text('导出诊断信息'),
                  subtitle: const Text(
                    '版本、连接状态、缓存统计、当前播放与最近错误',
                    style: TextStyle(fontSize: 12),
                  ),
                  trailing: const Icon(Icons.ios_share, color: Colors.grey),
                  onTap: _exportDiagnostics,
                ),
                _sectionTitle('连接'),
                ListTile(
                  leading: const Icon(Icons.cloud_outlined,
                      color: Color(0xFF7C9A9E)),
                  title: Text(WebDAVService.instance.baseUrl ?? '(未配置)'),
                  subtitle: Text(
                    '用户 ${WebDAVService.instance.username ?? '-'} · '
                    '${WebDAVService.instance.isConnected ? '已连接' : '未连接'}',
                    style: const TextStyle(fontSize: 12),
                  ),
                ),
                ListTile(
                  leading: const Icon(Icons.wifi_tethering,
                      color: Color(0xFF7C9A9E)),
                  title: const Text('测试连接'),
                  onTap: _testConnection,
                ),
                ListTile(
                  leading:
                      const Icon(Icons.logout, color: Colors.redAccent),
                  title: const Text('退出登录'),
                  subtitle: const Text(
                    '清除本机保存的 WebDAV 账号',
                    style: TextStyle(fontSize: 12),
                  ),
                  onTap: _logout,
                ),
                _sectionTitle('关于'),
                ListTile(
                  leading:
                      const Icon(Icons.info_outline, color: Color(0xFF7C9A9E)),
                  title: const Text('清听'),
                  subtitle: const Text(
                    '版本 $kAppVersion ($kAppBuild)\n'
                    '播放内核 media_kit (libmpv, LGPL/GPL) · UI Flutter (BSD)',
                    style: TextStyle(fontSize: 12),
                  ),
                ),
                const SizedBox(height: 24),
              ],
            ),
    );
  }

  Widget _sectionTitle(String text) {
    return Padding(
      padding: const EdgeInsets.fromLTRB(4, 20, 4, 8),
      child: Text(
        text,
        style: const TextStyle(
          fontSize: 13,
          fontWeight: FontWeight.w600,
          color: Color(0xFFB8D4D0),
          letterSpacing: 1.2,
        ),
      ),
    );
  }
}