import 'package:shared_preferences/shared_preferences.dart'; class AuthService { static const _tokenKey = 'auth_token'; static const _userIdKey = 'user_id'; Future saveAuth({required String token, String? userId}) async { final prefs = await SharedPreferences.getInstance(); await prefs.setString(_tokenKey, token); if (userId != null) await prefs.setString(_userIdKey, userId); } Future getToken() async { final prefs = await SharedPreferences.getInstance(); return prefs.getString(_tokenKey); } Future getUserId() async { final prefs = await SharedPreferences.getInstance(); return prefs.getString(_userIdKey); } Future isLoggedIn() async { final token = await getToken(); return token != null && token.isNotEmpty; } Future logout() async { final prefs = await SharedPreferences.getInstance(); await prefs.remove(_tokenKey); await prefs.remove(_userIdKey); } }