import 'package:shared_preferences/shared_preferences.dart';


class SpTool {
  static SharedPreferences? _instance;
  static final String _basePrefix = "app.";
  static Future<SharedPreferences>? _instanceFuture;

  static Future<SharedPreferences> getInstance() {
    if (_instance != null) {
      return Future.value(_instance);
    }

    _instanceFuture ??= SharedPreferences.getInstance().then((prefs) {
      _instance = prefs;
      return prefs;
    });

    return _instanceFuture!;
  }

  void setString(String key, String value) async {
    final prefs = await getInstance();
    prefs.setString("$_basePrefix$key", value);
  }

  Future<String> getString(String key) async {
    final prefs = await getInstance();
    return prefs.getString("$_basePrefix$key") ?? '';
  }

  void setBool(String key, bool value) async {
    final prefs = await getInstance();
    prefs.setBool("$_basePrefix$key", value);
  }

  Future<bool> getBool(String key) async {
    final prefs = await getInstance();
    return prefs.getBool("$_basePrefix$key") ?? false;
  }

  void setInt(String key, int value) async {
    final prefs = await getInstance();
    prefs.setInt("$_basePrefix$key", value);
  }

  Future<int> getInt(String key) async {
    final prefs = await getInstance();
    return prefs.getInt("$_basePrefix$key") ?? 0;
  }

  void deleteKey(String key) async {
    final prefs = await getInstance();
    prefs.remove("$_basePrefix$key");
  }
}