added cargo files

PinePods-0.8.2/mobile/lib/state/persistent_state.dart

@@ -0,0 +1,95 @@
+// Copyright 2020 Ben Hills. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:pinepods_mobile/entities/persistable.dart';
+import 'package:path/path.dart';
+import 'package:path_provider/path_provider.dart';
+
+class PersistentState {
+  static Future<void> persistState(Persistable persistable) async {
+    var d = await getApplicationSupportDirectory();
+
+    var file = File(join(d.path, 'state.json'));
+    var sink = file.openWrite();
+    var json = jsonEncode(persistable.toMap());
+
+    sink.write(json);
+    await sink.flush();
+    await sink.close();
+  }
+
+  static Future<Persistable> fetchState() async {
+    var d = await getApplicationSupportDirectory();
+
+    var file = File(join(d.path, 'state.json'));
+    var p = Persistable.empty();
+
+    if (file.existsSync()) {
+      var result = file.readAsStringSync();
+
+      if (result.isNotEmpty) {
+        var data = jsonDecode(result) as Map<String, dynamic>;
+
+        p = Persistable.fromMap(data);
+      }
+    }
+
+    return Future.value(p);
+  }
+
+  static Future<void> clearState() async {
+    var file = await _getFile();
+
+    if (file.existsSync()) {
+      file.delete();
+    }
+  }
+
+  static Future<void> writeInt(String name, int value) async {
+    return _writeValue(name, value.toString());
+  }
+
+  static Future<int> readInt(String name) async {
+    var result = await _readValue(name);
+
+    return result.isEmpty ? 0 : int.parse(result);
+  }
+
+  static Future<void> writeString(String name, String value) async {
+    return _writeValue(name, value);
+  }
+
+  static Future<String> readString(String name) async {
+    return _readValue(name);
+  }
+
+  static Future<String> _readValue(String name) async {
+    var d = await getApplicationSupportDirectory();
+
+    var file = File(join(d.path, name));
+    var result = file.readAsStringSync();
+
+    return result;
+  }
+
+  static Future<void> _writeValue(String name, String value) async {
+    var d = await getApplicationSupportDirectory();
+
+    var file = File(join(d.path, name));
+    var sink = file.openWrite();
+
+    sink.write(value.toString());
+    await sink.flush();
+    await sink.close();
+  }
+
+  static Future<File> _getFile() async {
+    var d = await getApplicationSupportDirectory();
+
+    return File(join(d.path, 'state.json'));
+  }
+}