feat: add arch

lib/core/utils/app_exceptions.dart

@@ -0,0 +1,21 @@
+class AppException implements Exception {
+  final String message;
+  final String prefix;
+
+  AppException([this.message = 'An unknown error occurred.', this.prefix = '']);
+
+  @override
+  String toString() {
+    return '$prefix$message';
+  }
+}
+
+class FetchDataException extends AppException {
+  FetchDataException([String? message])
+    : super(message ?? 'Error During Communication: ', 'Network Error');
+}
+
+class AuthenticationException extends AppException {
+  AuthenticationException([String? message])
+    : super(message ?? 'Authentication Failed.', 'Auth Error');
+}

lib/core/utils/result.dart

@@ -0,0 +1,31 @@
+sealed class Result<T> {
+  const Result();
+
+  /// Creates a successful [Result], completed with the specified [value].
+  const factory Result.ok(T value) = Ok._;
+
+  /// Creates an error [Result], completed with the specified [error].
+  const factory Result.error(Exception error) = Error._;
+}
+
+/// Subclass of Result for values
+final class Ok<T> extends Result<T> {
+  const Ok._(this.value);
+
+  /// Returned value in result
+  final T value;
+
+  @override
+  String toString() => 'Result<$T>.ok($value)';
+}
+
+/// Subclass of Result for errors
+final class Error<T> extends Result<T> {
+  const Error._(this.error);
+
+  /// Returned error in result
+  final Exception error;
+
+  @override
+  String toString() => 'Result<$T>.error($error)';
+}

lib/data/models/user_model.dart

@@ -0,0 +1,6 @@
+class UserModel {
+  final String token;
+  final String name;
+
+  UserModel({required this.token, required this.name});
+}

lib/data/repositories/auth_repository.dart

@@ -0,0 +1,24 @@
+import 'package:tm_app/core/utils/result.dart';
+
+import '../../core/utils/app_exceptions.dart';
+import '../models/user_model.dart';
+import '../services/auth_service.dart';
+
+class AuthRepository {
+  final AuthService _authService;
+
+  AuthRepository(this._authService);
+
+  Future<Result<UserModel>> login(String email, String password) async {
+    try {
+      final response = await _authService.login(email, password);
+      final user = UserModel(token: response['token'], name: response['name']);
+      return Result.ok(user); // در حالت موفقیت، یک Ok برمی‌گرداند
+    } catch (e) {
+      // در حالت خطا، یک Error برمی‌گرداند
+      return Result.error(
+        AuthenticationException('Email or password is not correct.'),
+      );
+    }
+  }
+}

lib/data/services/auth_service.dart

@@ -0,0 +1,12 @@
+class AuthService {
+  Future<Map<String, dynamic>> login(String email, String password) async {
+    // شبیه‌سازی API Call
+    await Future.delayed(const Duration(seconds: 2));
+
+    if (email == 'test@example.com' && password == 'password123') {
+      return {'token': 'xyz123', 'name': 'John Doe'};
+    } else {
+      throw Exception('Invalid credentials');
+    }
+  }
+}

lib/main.dart

@@ -1,122 +1,37 @@
+// main.dart
 import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+
+import 'data/repositories/auth_repository.dart';
+import 'data/services/auth_service.dart';
+import 'view_models/auth_view_model.dart';
+import 'views/login_screen.dart';
 
 void main() {
-  runApp(const MyApp());
+  runApp(
+    MultiProvider(
+      providers: [
+        Provider(create: (_) => AuthService()),
+        ProxyProvider<AuthService, AuthRepository>(
+          update: (_, authService, __) => AuthRepository(authService),
+        ),
+        ChangeNotifierProvider(
+          create:
+              (context) => AuthViewModel(
+                Provider.of<AuthRepository>(context, listen: false),
+              ),
+        ),
+      ],
+      child: const MyApp(),
+    ),
+  );
 }
 
 class MyApp extends StatelessWidget {
   const MyApp({super.key});
 
-  // This widget is the root of your application.
   @override
   Widget build(BuildContext context) {
-    return MaterialApp(
+    return const MaterialApp(home: LoginScreen());
-      title: 'Flutter Demo',
-      theme: ThemeData(
-        // This is the theme of your application.
-        //
-        // TRY THIS: Try running your application with "flutter run". You'll see
-        // the application has a purple toolbar. Then, without quitting the app,
-        // try changing the seedColor in the colorScheme below to Colors.green
-        // and then invoke "hot reload" (save your changes or press the "hot
-        // reload" button in a Flutter-supported IDE, or press "r" if you used
-        // the command line to start the app).
-        //
-        // Notice that the counter didn't reset back to zero; the application
-        // state is not lost during the reload. To reset the state, use hot
-        // restart instead.
-        //
-        // This works for code too, not just values: Most code changes can be
-        // tested with just a hot reload.
-        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
-      ),
-      home: const MyHomePage(title: 'Flutter Demo Home Page'),
-    );
-  }
-}
-
-class MyHomePage extends StatefulWidget {
-  const MyHomePage({super.key, required this.title});
-
-  // This widget is the home page of your application. It is stateful, meaning
-  // that it has a State object (defined below) that contains fields that affect
-  // how it looks.
-
-  // This class is the configuration for the state. It holds the values (in this
-  // case the title) provided by the parent (in this case the App widget) and
-  // used by the build method of the State. Fields in a Widget subclass are
-  // always marked "final".
-
-  final String title;
-
-  @override
-  State<MyHomePage> createState() => _MyHomePageState();
-}
-
-class _MyHomePageState extends State<MyHomePage> {
-  int _counter = 0;
-
-  void _incrementCounter() {
-    setState(() {
-      // This call to setState tells the Flutter framework that something has
-      // changed in this State, which causes it to rerun the build method below
-      // so that the display can reflect the updated values. If we changed
-      // _counter without calling setState(), then the build method would not be
-      // called again, and so nothing would appear to happen.
-      _counter++;
-    });
-  }
-
-  @override
-  Widget build(BuildContext context) {
-    // This method is rerun every time setState is called, for instance as done
-    // by the _incrementCounter method above.
-    //
-    // The Flutter framework has been optimized to make rerunning build methods
-    // fast, so that you can just rebuild anything that needs updating rather
-    // than having to individually change instances of widgets.
-    return Scaffold(
-      appBar: AppBar(
-        // TRY THIS: Try changing the color here to a specific color (to
-        // Colors.amber, perhaps?) and trigger a hot reload to see the AppBar
-        // change color while the other colors stay the same.
-        backgroundColor: Theme.of(context).colorScheme.inversePrimary,
-        // Here we take the value from the MyHomePage object that was created by
-        // the App.build method, and use it to set our appbar title.
-        title: Text(widget.title),
-      ),
-      body: Center(
-        // Center is a layout widget. It takes a single child and positions it
-        // in the middle of the parent.
-        child: Column(
-          // Column is also a layout widget. It takes a list of children and
-          // arranges them vertically. By default, it sizes itself to fit its
-          // children horizontally, and tries to be as tall as its parent.
-          //
-          // Column has various properties to control how it sizes itself and
-          // how it positions its children. Here we use mainAxisAlignment to
-          // center the children vertically; the main axis here is the vertical
-          // axis because Columns are vertical (the cross axis would be
-          // horizontal).
-          //
-          // TRY THIS: Invoke "debug painting" (choose the "Toggle Debug Paint"
-          // action in the IDE, or press "p" in the console), to see the
-          // wireframe for each widget.
-          mainAxisAlignment: MainAxisAlignment.center,
-          children: <Widget>[
-            const Text('You have pushed the button this many times:'),
-            Text(
-              '$_counter',
-              style: Theme.of(context).textTheme.headlineMedium,
-            ),
-          ],
-        ),
-      ),
-      floatingActionButton: FloatingActionButton(
-        onPressed: _incrementCounter,
-        tooltip: 'Increment',
-        child: const Icon(Icons.add),
-      ), // This trailing comma makes auto-formatting nicer for build methods.
-    );
   }
 }

lib/view_models/auth_view_model.dart

@@ -0,0 +1,41 @@
+import 'package:flutter/material.dart';
+
+import '../core/utils/result.dart';
+import '../data/models/user_model.dart';
+import '../data/repositories/auth_repository.dart';
+
+class AuthViewModel with ChangeNotifier {
+  final AuthRepository _authRepository;
+
+  AuthViewModel(this._authRepository);
+
+  bool _isLoading = false;
+  String? _errorMessage;
+  UserModel? _loggedInUser;
+
+  bool get isLoading => _isLoading;
+  String? get errorMessage => _errorMessage;
+  UserModel? get loggedInUser => _loggedInUser;
+
+  Future<void> login(String email, String password) async {
+    _isLoading = true;
+    _errorMessage = null;
+    notifyListeners();
+
+    final result = await _authRepository.login(email, password);
+
+    switch (result) {
+      case Ok<UserModel>():
+        _loggedInUser = result.value;
+        // موفقیت‌آمیز
+        break;
+      case Error<UserModel>():
+        _errorMessage = result.error.toString();
+        // خطا
+        break;
+    }
+
+    _isLoading = false;
+    notifyListeners();
+  }
+}

lib/views/login_screen.dart

@@ -0,0 +1,71 @@
+// lib/views/login_screen.dart
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+
+import '../view_models/auth_view_model.dart';
+
+class LoginScreen extends StatefulWidget {
+  const LoginScreen({super.key});
+
+  @override
+  State<LoginScreen> createState() => _LoginScreenState();
+}
+
+class _LoginScreenState extends State<LoginScreen> {
+  final _emailController = TextEditingController();
+  final _passwordController = TextEditingController();
+
+  @override
+  Widget build(BuildContext context) {
+    final authViewModel = Provider.of<AuthViewModel>(context);
+
+    return Scaffold(
+      appBar: AppBar(title: const Text('Login')),
+      body: Padding(
+        padding: const EdgeInsets.all(16.0),
+        child: Column(
+          children: [
+            TextField(
+              controller: _emailController,
+              decoration: const InputDecoration(labelText: 'Email'),
+            ),
+            TextField(
+              controller: _passwordController,
+              decoration: const InputDecoration(labelText: 'Password'),
+              obscureText: true,
+            ),
+            const SizedBox(height: 20),
+            if (authViewModel.isLoading)
+              const CircularProgressIndicator()
+            else
+              ElevatedButton(
+                onPressed: () {
+                  authViewModel.login(
+                    _emailController.text,
+                    _passwordController.text,
+                  );
+                },
+                child: const Text('Login'),
+              ),
+            if (authViewModel.errorMessage != null)
+              Padding(
+                padding: const EdgeInsets.only(top: 20),
+                child: Text(
+                  authViewModel.errorMessage!,
+                  style: const TextStyle(color: Colors.red),
+                ),
+              ),
+            if (authViewModel.loggedInUser != null)
+              Padding(
+                padding: const EdgeInsets.only(top: 20),
+                child: Text(
+                  'Welcome, ${authViewModel.loggedInUser!.name}!',
+                  style: const TextStyle(color: Colors.green),
+                ),
+              ),
+          ],
+        ),
+      ),
+    );
+  }
+}