car-interface-android/lib/data/services/secure_store.dart

import 'package:flutter_secure_storage/flutter_secure_storage.dart';

/// Small abstraction so the PIN hashing logic can be tested without Android.
abstract class SecureStore {
  Future<String?> read(String key);

  Future<void> write(String key, String value);

  Future<void> delete(String key);
}

class FlutterSecureStore implements SecureStore {
  FlutterSecureStore([FlutterSecureStorage? storage])
    : _storage = storage ?? const FlutterSecureStorage();

  final FlutterSecureStorage _storage;

  @override
  Future<String?> read(String key) => _storage.read(key: key);

  @override
  Future<void> write(String key, String value) =>
      _storage.write(key: key, value: value);

  @override
  Future<void> delete(String key) => _storage.delete(key: key);
}