import 'dart:io';

import 'package:archive/archive_io.dart';
import 'package:cloud_archiver/config.dart';
import 'package:cloud_archiver/state.dart';
import 'package:filesize/filesize.dart';
import 'package:flutter/material.dart';
import 'package:path/path.dart';
import 'package:path_provider/path_provider.dart';
import 'package:webdav_client/webdav_client.dart' as dav;

late dav.Client _client;

String totalSize() {
  if (cloudArchives.value.isEmpty) return '0 MB';
  return filesize(
    cloudArchives.value.values
        .map((archives) => archives.map((archive) => archive.size ?? 0).reduce((total, size) => total + size))
        .reduce((total, size) => total + size),
    1,
  );
}

Future<bool> connect(String server, String user, String auth) async {
  var client = dav.newClient(
    server,
    debug: true,
    user: user,
    password: auth,
  );
  client.setHeaders({'accept-charset': 'utf-8'});

  client.setConnectTimeout(5 * 1000);

  // Set send data timeout time in milliseconds.
  client.setSendTimeout(60 * 1000);

  // Set transfer data time in milliseconds.
  client.setReceiveTimeout(60 * 1000);

  try {
    davStatus.value = DavStatus.loading;
    await client.ping();
    davStatus.value = DavStatus.connected;
    _client = client;
    return true;
  } catch (e) {
    print('$e');
    davStatus.value = DavStatus.notConnected;
  }
  return false;
}

void loadLocalStatus() {
  if (appConfig?.syncItems.isNotEmpty != true) return;
  var result = <SyncItemConfig, DateTime?>{};
  for (var syncItem in appConfig!.syncItems) {
    var file = File(syncItem.path);
    var stat = file.statSync();
    switch (stat.type) {
      case FileSystemEntityType.file:
        result[syncItem] = stat.modified;
      case FileSystemEntityType.directory:
        result[syncItem] = dirModifiedTime(syncItem.path);
      default:
        result[syncItem] = null;
    }
  }

  localSyncItems.value = {
    ...localSyncItems.value,
    ...result,
  };
}

DateTime dirModifiedTime(String dir) {
  var directory = Directory(dir);
  var modified = directory.statSync().modified;
  for (var entry in Directory(dir).listSync(recursive: true)) {
    var stat = entry.statSync();
    if (stat.type == FileSystemEntityType.file) {
      if (stat.modified.isAfter(modified)) {
        modified = stat.modified;
      }
    }
  }
  return modified;
}

void loadCloudArchives() async {
  if (davStatus.value != DavStatus.connected) return;
  davStatus.value = DavStatus.loading;
  List<dav.File> list = [];
  try {
    list = await _client.readDir('/');
  } catch (e) {
    print(e);
    davStatus.value = DavStatus.notConnected;
    return;
  }
  var result = <String, List<dav.File>>{};
  for (var item in list) {
    if (item.isDir == true && item.path?.isNotEmpty == true) {
      var files = await _client.readDir(item.path!);
      result[basename(item.path!)] = files;
    }
  }

  cloudArchives.value = result;
  davStatus.value = DavStatus.connected;
}

Future<void> upload(BuildContext context, SyncItemConfig item, bool needCreateDir) async {
  if (needCreateDir) {
    await _client.mkdir(item.name);
  }
  var file = File(item.path);

  var cacheDir = await getApplicationCacheDirectory();

  var zipFileEncoder = ZipFileEncoder();
  var zipFileName = '${appConfig?.client ?? 'DEBUG'}-${DateTime.now().strFileName}.zip';
  var zipTempFilePath = join(cacheDir.path, zipFileName);
  zipFileEncoder.create(zipTempFilePath);
  if (file.statSync().type == FileSystemEntityType.directory) {
    var directory = Directory(item.path);
    for (var file in directory.listSync()) {
      print('Add file: ${file.path}');
    }
    await zipFileEncoder.addDirectory(
      directory,
      onProgress: (progress) {
        print('Zip progress: $progress');
      },
    );
  } else {
    await zipFileEncoder.addFile(file);
  }

  await zipFileEncoder.close();
  await _client.writeFromFile(zipTempFilePath, join(item.name, zipFileName));

  File(zipTempFilePath).delete();
  if (context.mounted) {
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        content: Text('上传完成'),
      ),
    );
  }
  loadCloudArchives();
}

Future<void> download(BuildContext context, SyncItemConfig item, dav.File cloudArchive) async {
  print('Start download: ${cloudArchive.path}');
  var cacheDir = await getApplicationCacheDirectory();
  var zipPath = join(cacheDir.path, '${item.name}_${cloudArchive.name}');
  await _client.read2File(
    cloudArchive.path!,
    zipPath,
    onProgress: (count, total) {
      print('Downloaded: $count/$total');
    },
  );
  await extractFileToDisk(
    zipPath,
    cacheDir.path,
    callback: (entry) {
      print('Unzip: ${entry.name}');
    },
  );
  File(zipPath).delete();

  var temp = File(join(cacheDir.path, basename(item.path)));
  print('Temp path: ${temp.path}');
  var fileSystemEntityType = temp.statSync().type;

  switch (fileSystemEntityType) {
    case FileSystemEntityType.directory:
      var directory = Directory(item.path);
      if (directory.existsSync()) {
        directory.deleteSync(recursive: true);
      }
      await Directory(temp.path).safeMoveDirectory(item.path);
    case FileSystemEntityType.file:
      var file = File(item.path);
      if (file.existsSync()) {
        file.deleteSync();
      }
      await temp.safeMoveFile(item.path);
    default:
      print('Failed: $fileSystemEntityType');
  }

  loadLocalStatus();

  if (context.mounted) {
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        content: Text('下载完成'),
      ),
    );
  }
}

extension DateTimeExt on DateTime {
  String get strHm => '$year/${padZero(month)}/${padZero(day)} ${padZero(hour)}:${padZero(minute)}';

  String get strHms => '$strHm:${padZero(second)}';

  String get strFileName => '${year}_${padZero(month)}_${padZero(day)}_${padZero(hour)}_${padZero(minute)}_${padZero(second)}';

  String padZero(int num, [fix = 2]) => num.toString().padLeft(fix, '0');
}

/// 安全地移动文件和目录（支持跨分区）

extension on File {
  Future<void> safeMoveFile(String destPath) async {
    try {
      await rename(destPath);
      return;
    } on FileSystemException catch (e) {
      // 捕获到 errno = 18 (EXDEV) 跨分区错误时，退化到“复制+删除”方案
      if (e.osError?.errorCode != 18) {
        rethrow; // 其他错误继续抛出
      }
    }

    await copy(destPath);

    await delete();
  }
}

extension on Directory {
  Future<void> safeMoveDirectory(String destPath) async {
    // 1. 如果在同一分区，优先尝试 rename，效率最高
    try {
      await rename(destPath);
      return;
    } on FileSystemException catch (e) {
      // 捕获到 errno = 18 (EXDEV) 跨分区错误时，退化到“复制+删除”方案
      if (e.osError?.errorCode != 18) {
        rethrow; // 其他错误继续抛出
      }
    }

    // 2. 跨分区移动：递归复制
    await _copyDirectory(this, Directory(destPath));

    // 3. 复制完成后删除源目录
    await delete(recursive: true);
  }
}

/// 递归复制目录
Future<void> _copyDirectory(Directory source, Directory destination) async {
  // 确保目标目录存在
  await destination.create(recursive: true);

  await for (var entity in source.list(recursive: false)) {
    // 计算在新目录下的对应路径
    final newPath = '${destination.path}/${entity.uri.pathSegments.lastWhere((s) => s.isNotEmpty)}';

    if (entity is File) {
      await entity.copy(newPath);
    } else if (entity is Directory) {
      await _copyDirectory(entity, Directory(newPath));
    }
  }
}