upstream-flutter-samples/compass_app/app/lib/data/services/shared_preferences_service.dart

// Copyright 2024 The Flutter team. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'package:logging/logging.dart';
import 'package:shared_preferences/shared_preferences.dart';

import '../../utils/result.dart';

class SharedPreferencesService {
  static const _tokenKey = 'TOKEN';
  final _log = Logger('SharedPreferencesService');

  Future<Result<String?>> fetchToken() async {
    try {
      final sharedPreferences = SharedPreferencesAsync();

      _log.finer('Got token from SharedPreferences');

      return Result.ok(await sharedPreferences.getString(_tokenKey));
    } on Exception catch (e) {
      _log.warning('Failed to get token', e);
      return Result.error(e);
    }
  }

  Future<Result<void>> saveToken(String? token) async {
    try {
      final sharedPreferences = SharedPreferencesAsync();

      if (token == null) {
        _log.finer('Removed token');

        await sharedPreferences.remove(_tokenKey);
      } else {
        _log.finer('Replaced token');

        await sharedPreferences.setString(_tokenKey, token);
      }

      return const Result.ok(null);
    } on Exception catch (e) {
      _log.warning('Failed to set token', e);
      return Result.error(e);
    }
  }
}