feat: webdav

Closes #432

Signed-off-by: bggRGjQaUbCoE <githubaccount56556@proton.me>

lib/pages/webdav/webdav.dart

@@ -0,0 +1,88 @@
+import 'dart:convert';
+import 'dart:io';
+import 'package:PiliPlus/utils/extension.dart';
+import 'package:PiliPlus/utils/storage.dart';
+import 'package:flutter_smart_dialog/flutter_smart_dialog.dart';
+import 'package:webdav_client/webdav_client.dart' as webdav;
+
+class WebDav {
+  late String _webDavUri;
+  late String _webDavUsername;
+  late String _webDavPassword;
+  late String _webdavDirectory;
+
+  webdav.Client? _client;
+
+  WebDav._internal();
+  static final WebDav _instance = WebDav._internal();
+  factory WebDav() => _instance;
+
+  Future<bool> init() async {
+    _webDavUri = GStorage.webdavUri;
+    _webDavUsername = GStorage.webdavUsername;
+    _webDavPassword = GStorage.webdavPassword;
+    _webdavDirectory = GStorage.webdavDirectory;
+    if (_webdavDirectory.endsWith('/').not) {
+      _webdavDirectory += '/';
+    }
+    _webdavDirectory += 'PiliPlus';
+
+    try {
+      _client = null;
+      final client = webdav.newClient(
+        _webDavUri,
+        user: _webDavUsername,
+        password: _webDavPassword,
+      )
+        ..setHeaders({'accept-charset': 'utf-8'})
+        ..setConnectTimeout(4000)
+        ..setReceiveTimeout(4000)
+        ..setSendTimeout(4000);
+
+      await client.mkdirAll(_webdavDirectory);
+
+      _client = client;
+      return true;
+    } catch (_) {
+      return false;
+    }
+  }
+
+  Future backup() async {
+    if (_client == null) {
+      if (await init() == false) {
+        SmartDialog.showToast('备份失败，请检查配置');
+        return;
+      }
+    }
+    try {
+      final path = '$_webdavDirectory/piliplus_settings.json';
+      final file = File(path);
+      if (await file.exists()) {
+        await file.delete();
+      }
+      String data = await GStorage.exportAllSettings();
+      await _client!.write(path, utf8.encode(data));
+      SmartDialog.showToast('备份成功');
+    } catch (e) {
+      SmartDialog.showToast('备份失败: $e');
+    }
+  }
+
+  Future restore() async {
+    if (_client == null) {
+      if (await init() == false) {
+        SmartDialog.showToast('恢复失败，请检查配置');
+        return;
+      }
+    }
+    try {
+      final path = '$_webdavDirectory/piliplus_settings.json';
+      final data = await _client!.read(path);
+      await GStorage.importAllSettings(utf8.decode(data));
+      SmartDialog.showToast('恢复成功');
+    } catch (e) {
+      SmartDialog.showToast('恢复失败: $e');
+    }
+  }
+}