add price policy

CODE_EXAMPLES.md

@@ -0,0 +1,772 @@
+# Flutter Code Examples & Patterns
+
+This document contains all Dart code examples and patterns referenced in `CLAUDE.md`. Use these as templates when implementing features in the Worker app.
+
+---
+
+## Table of Contents
+- [Best Practices](#best-practices)
+- [UI/UX Components](#uiux-components)
+- [State Management](#state-management)
+- [Performance Optimization](#performance-optimization)
+- [Offline Strategy](#offline-strategy)
+- [Localization](#localization)
+- [Deployment](#deployment)
+
+---
+
+## Best Practices
+
+### Hive Box Type Management
+
+**✅ CORRECT - Use Box<dynamic> with type filtering**
+```dart
+Box<dynamic> get _box {
+  return Hive.box<dynamic>(HiveBoxNames.favoriteBox);
+}
+
+Future<List<FavoriteModel>> getAllFavorites(String userId) async {
+  try {
+    final favorites = _box.values
+        .whereType<FavoriteModel>()  // Type-safe filtering
+        .where((fav) => fav.userId == userId)
+        .toList();
+    return favorites;
+  } catch (e) {
+    debugPrint('[DataSource] Error: $e');
+    rethrow;
+  }
+}
+
+Future<List<FavoriteModel>> getAllFavorites() async {
+  return _box.values
+    .whereType<FavoriteModel>()  // Type-safe!
+    .where((fav) => fav.userId == userId)
+    .toList();
+}
+```
+
+**❌ INCORRECT - Will cause HiveError**
+```dart
+Box<FavoriteModel> get _box {
+  return Hive.box<FavoriteModel>(HiveBoxNames.favoriteBox);
+}
+```
+
+**Reason**: Hive boxes are opened as `Box<dynamic>` in the central HiveService. Re-opening with a specific type causes `HiveError: The box is already open and of type Box<dynamic>`.
+
+### AppBar Standardization
+
+**Standard AppBar Pattern** (reference: `products_page.dart`):
+```dart
+AppBar(
+  leading: IconButton(
+    icon: const Icon(Icons.arrow_back, color: Colors.black),
+    onPressed: () => context.pop(),
+  ),
+  title: const Text('Page Title', style: TextStyle(color: Colors.black)),
+  elevation: AppBarSpecs.elevation,
+  backgroundColor: AppColors.white,
+  foregroundColor: AppColors.grey900,
+  centerTitle: false,
+  actions: [
+    // Custom actions here
+    const SizedBox(width: AppSpacing.sm), // Always end with spacing
+  ],
+)
+```
+
+**For SliverAppBar** (in CustomScrollView):
+```dart
+SliverAppBar(
+  pinned: true,
+  backgroundColor: AppColors.white,
+  foregroundColor: AppColors.grey900,
+  elevation: AppBarSpecs.elevation,
+  leading: IconButton(
+    icon: const Icon(Icons.arrow_back, color: Colors.black),
+    onPressed: () => context.pop(),
+  ),
+  title: const Text('Page Title', style: TextStyle(color: Colors.black)),
+  centerTitle: false,
+  actions: [
+    // Custom actions
+    const SizedBox(width: AppSpacing.sm),
+  ],
+)
+```
+
+**Standard Pattern (Recent Implementation)**:
+```dart
+AppBar(
+  leading: IconButton(
+    icon: const Icon(Icons.arrow_back, color: Colors.black),
+    onPressed: () => context.pop(),
+  ),
+  title: const Text('Title', style: TextStyle(color: Colors.black)),
+  elevation: AppBarSpecs.elevation,
+  backgroundColor: AppColors.white,
+  foregroundColor: AppColors.grey900,
+  centerTitle: false,
+  actions: [..., const SizedBox(width: AppSpacing.sm)],
+)
+```
+
+---
+
+## UI/UX Components
+
+### Color Palette
+
+```dart
+// colors.dart
+class AppColors {
+  // Primary
+  static const primaryBlue = Color(0xFF005B9A);
+  static const lightBlue = Color(0xFF38B6FF);
+  static const accentCyan = Color(0xFF35C6F4);
+
+  // Status
+  static const success = Color(0xFF28a745);
+  static const warning = Color(0xFFffc107);
+  static const danger = Color(0xFFdc3545);
+  static const info = Color(0xFF17a2b8);
+
+  // Neutrals
+  static const grey50 = Color(0xFFf8f9fa);
+  static const grey100 = Color(0xFFe9ecef);
+  static const grey500 = Color(0xFF6c757d);
+  static const grey900 = Color(0xFF343a40);
+
+  // Tier Gradients
+  static const diamondGradient = LinearGradient(
+    colors: [Color(0xFF4A00E0), Color(0xFF8E2DE2)],
+    begin: Alignment.topLeft,
+    end: Alignment.bottomRight,
+  );
+
+  static const platinumGradient = LinearGradient(
+    colors: [Color(0xFF7F8C8D), Color(0xFFBDC3C7)],
+    begin: Alignment.topLeft,
+    end: Alignment.bottomRight,
+  );
+
+  static const goldGradient = LinearGradient(
+    colors: [Color(0xFFf7b733), Color(0xFFfc4a1a)],
+    begin: Alignment.topLeft,
+    end: Alignment.bottomRight,
+  );
+}
+```
+
+### Typography
+
+```dart
+// typography.dart
+class AppTypography {
+  static const fontFamily = 'Roboto';
+
+  static const displayLarge = TextStyle(
+    fontSize: 32,
+    fontWeight: FontWeight.bold,
+    fontFamily: fontFamily,
+  );
+
+  static const headlineLarge = TextStyle(
+    fontSize: 24,
+    fontWeight: FontWeight.w600,
+    fontFamily: fontFamily,
+  );
+
+  static const titleLarge = TextStyle(
+    fontSize: 20,
+    fontWeight: FontWeight.w500,
+    fontFamily: fontFamily,
+  );
+
+  static const bodyLarge = TextStyle(
+    fontSize: 16,
+    fontWeight: FontWeight.normal,
+    fontFamily: fontFamily,
+  );
+
+  static const labelSmall = TextStyle(
+    fontSize: 12,
+    fontWeight: FontWeight.normal,
+    fontFamily: fontFamily,
+  );
+}
+```
+
+### Member Card Design
+
+```dart
+class MemberCardSpecs {
+  static const double width = double.infinity;
+  static const double height = 200;
+  static const double borderRadius = 16;
+  static const double elevation = 8;
+  static const EdgeInsets padding = EdgeInsets.all(20);
+
+  // QR Code
+  static const double qrSize = 80;
+  static const double qrBackgroundSize = 90;
+
+  // Points Display
+  static const double pointsFontSize = 28;
+  static const FontWeight pointsFontWeight = FontWeight.bold;
+}
+```
+
+### Status Badges
+
+```dart
+class StatusBadge extends StatelessWidget {
+  final String status;
+  final Color color;
+
+  static Color getColorForStatus(OrderStatus status) {
+    switch (status) {
+      case OrderStatus.pending:
+        return AppColors.info;
+      case OrderStatus.processing:
+        return AppColors.warning;
+      case OrderStatus.shipping:
+        return AppColors.lightBlue;
+      case OrderStatus.completed:
+        return AppColors.success;
+      case OrderStatus.cancelled:
+        return AppColors.danger;
+    }
+  }
+}
+```
+
+### Bottom Navigation
+
+```dart
+class BottomNavSpecs {
+  static const double height = 72;
+  static const double iconSize = 24;
+  static const double selectedIconSize = 28;
+  static const double labelFontSize = 12;
+  static const Color selectedColor = AppColors.primaryBlue;
+  static const Color unselectedColor = AppColors.grey500;
+}
+```
+
+### Floating Action Button
+
+```dart
+class FABSpecs {
+  static const double size = 56;
+  static const double elevation = 6;
+  static const Color backgroundColor = AppColors.accentCyan;
+  static const Color iconColor = Colors.white;
+  static const double iconSize = 24;
+  static const Offset position = Offset(16, 16); // from bottom-right
+}
+```
+
+### AppBar Specifications
+
+```dart
+class AppBarSpecs {
+  // From ui_constants.dart
+  static const double elevation = 0.5;
+
+  // Standard pattern for all pages
+  static AppBar standard({
+    required String title,
+    required VoidCallback onBack,
+    List<Widget>? actions,
+  }) {
+    return AppBar(
+      leading: IconButton(
+        icon: const Icon(Icons.arrow_back, color: Colors.black),
+        onPressed: onBack,
+      ),
+      title: Text(title, style: const TextStyle(color: Colors.black)),
+      elevation: elevation,
+      backgroundColor: AppColors.white,
+      foregroundColor: AppColors.grey900,
+      centerTitle: false,
+      actions: [
+        ...?actions,
+        const SizedBox(width: AppSpacing.sm),
+      ],
+    );
+  }
+}
+```
+
+---
+
+## State Management
+
+### Authentication Providers
+
+```dart
+final authProvider = AsyncNotifierProvider<AuthNotifier, AuthState>
+final otpTimerProvider = StateNotifierProvider<OTPTimerNotifier, int>
+```
+
+### Home Providers
+
+```dart
+final memberCardProvider = Provider<MemberCard>((ref) {
+  final user = ref.watch(authProvider).user;
+  return MemberCard(
+    tier: user.memberTier,
+    name: user.name,
+    memberId: user.id,
+    points: user.points,
+    qrCode: generateQRCode(user.id),
+  );
+});
+```
+
+### Loyalty Providers
+
+```dart
+final loyaltyPointsProvider = AsyncNotifierProvider<LoyaltyPointsNotifier, LoyaltyPoints>
+```
+
+**Rewards Page Providers**:
+```dart
+// Providers in lib/features/loyalty/presentation/providers/
+@riverpod
+class LoyaltyPoints extends _$LoyaltyPoints {
+  // Manages 9,750 available points, 1,200 expiring
+}
+
+@riverpod
+class Gifts extends _$Gifts {
+  // 6 mock gifts matching HTML design
+}
+
+@riverpod
+List<GiftCatalog> filteredGifts(ref) {
+  // Filters by selected category
+}
+
+final selectedGiftCategoryProvider = StateNotifierProvider...
+final hasEnoughPointsProvider = Provider.family<bool, int>...
+```
+
+### Referral Provider
+
+```dart
+final referralProvider = AsyncNotifierProvider<ReferralNotifier, Referral>
+```
+
+### Products Providers
+
+```dart
+final productsProvider = AsyncNotifierProvider<ProductsNotifier, List<Product>>
+final productSearchProvider = StateProvider<String>
+final selectedCategoryProvider = StateProvider<String?>
+```
+
+### Cart Providers
+
+```dart
+final cartProvider = NotifierProvider<CartNotifier, List<CartItem>>
+final cartTotalProvider = Provider<double>
+```
+
+**Dynamic Cart Badge**:
+```dart
+// Added provider in cart_provider.dart
+@riverpod
+int cartItemCount(CartItemCountRef ref) {
+  final cartState = ref.watch(cartProvider);
+  return cartState.items.fold(0, (sum, item) => sum + item.quantity);
+}
+
+// Used in home_page.dart and products_page.dart
+final cartItemCount = ref.watch(cartItemCountProvider);
+QuickAction(
+  badge: cartItemCount > 0 ? '$cartItemCount' : null,
+)
+```
+
+### Orders Providers
+
+```dart
+final ordersProvider = AsyncNotifierProvider<OrdersNotifier, List<Order>>
+final orderFilterProvider = StateProvider<OrderStatus?>
+final paymentsProvider = AsyncNotifierProvider<PaymentsNotifier, List<Payment>>
+```
+
+### Projects Providers
+
+```dart
+final projectsProvider = AsyncNotifierProvider<ProjectsNotifier, List<Project>>
+final projectFormProvider = StateNotifierProvider<ProjectFormNotifier, ProjectFormState>
+```
+
+### Chat Providers
+
+```dart
+final chatProvider = AsyncNotifierProvider<ChatNotifier, ChatRoom>
+final messagesProvider = StreamProvider<List<Message>>
+final typingIndicatorProvider = StateProvider<bool>
+```
+
+### Authentication State Implementation
+
+```dart
+@riverpod
+class Auth extends _$Auth {
+  @override
+  Future<AuthState> build() async {
+    final token = await _getStoredToken();
+    if (token != null) {
+      final user = await _getUserFromToken(token);
+      return AuthState.authenticated(user);
+    }
+    return const AuthState.unauthenticated();
+  }
+
+  Future<void> loginWithPhone(String phone) async {
+    state = const AsyncValue.loading();
+    state = await AsyncValue.guard(() async {
+      await ref.read(authRepositoryProvider).requestOTP(phone);
+      return AuthState.otpSent(phone);
+    });
+  }
+
+  Future<void> verifyOTP(String phone, String otp) async {
+    state = const AsyncValue.loading();
+    state = await AsyncValue.guard(() async {
+      final response = await ref.read(authRepositoryProvider).verifyOTP(phone, otp);
+      await _storeToken(response.token);
+      return AuthState.authenticated(response.user);
+    });
+  }
+}
+```
+
+---
+
+## Performance Optimization
+
+### Image Caching
+
+```dart
+// Use cached_network_image for all remote images
+CachedNetworkImage(
+  imageUrl: product.images.first,
+  placeholder: (context, url) => const ShimmerPlaceholder(),
+  errorWidget: (context, url, error) => const Icon(Icons.error),
+  fit: BoxFit.cover,
+  memCacheWidth: 400, // Optimize memory usage
+  fadeInDuration: const Duration(milliseconds: 300),
+)
+```
+
+### List Performance
+
+```dart
+// Use ListView.builder with RepaintBoundary for long lists
+ListView.builder(
+  itemCount: items.length,
+  itemBuilder: (context, index) {
+    return RepaintBoundary(
+      child: ProductCard(product: items[index]),
+    );
+  },
+  cacheExtent: 1000, // Pre-render items
+)
+
+// Use AutomaticKeepAliveClientMixin for expensive widgets
+class ProductCard extends StatefulWidget {
+  @override
+  State<ProductCard> createState() => _ProductCardState();
+}
+
+class _ProductCardState extends State<ProductCard>
+    with AutomaticKeepAliveClientMixin {
+  @override
+  bool get wantKeepAlive => true;
+
+  @override
+  Widget build(BuildContext context) {
+    super.build(context);
+    return Card(...);
+  }
+}
+```
+
+### State Optimization
+
+```dart
+// Use .select() to avoid unnecessary rebuilds
+final userName = ref.watch(authProvider.select((state) => state.user?.name));
+
+// Use family modifiers for parameterized providers
+@riverpod
+Future<Product> product(ProductRef ref, String id) async {
+  return await ref.read(productRepositoryProvider).getProduct(id);
+}
+
+// Keep providers outside build method
+final productsProvider = ...;
+
+class ProductsPage extends ConsumerWidget {
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final products = ref.watch(productsProvider);
+    return ...;
+  }
+}
+```
+
+---
+
+## Offline Strategy
+
+### Data Sync Flow
+
+```dart
+@riverpod
+class DataSync extends _$DataSync {
+  @override
+  Future<SyncStatus> build() async {
+    // Listen to connectivity changes
+    ref.listen(connectivityProvider, (previous, next) {
+      if (next == ConnectivityStatus.connected) {
+        syncData();
+      }
+    });
+
+    return SyncStatus.idle;
+  }
+
+  Future<void> syncData() async {
+    state = const AsyncValue.loading();
+
+    state = await AsyncValue.guard(() async {
+      // Sync in order of dependency
+      await _syncUserData();
+      await _syncProducts();
+      await _syncOrders();
+      await _syncProjects();
+      await _syncLoyaltyData();
+
+      await ref.read(settingsRepositoryProvider).updateLastSyncTime();
+
+      return SyncStatus.success;
+    });
+  }
+
+  Future<void> _syncUserData() async {
+    final user = await ref.read(authRepositoryProvider).getCurrentUser();
+    await ref.read(authLocalDataSourceProvider).saveUser(user);
+  }
+
+  Future<void> _syncProducts() async {
+    final products = await ref.read(productRepositoryProvider).getAllProducts();
+    await ref.read(productLocalDataSourceProvider).saveProducts(products);
+  }
+
+  // ... other sync methods
+}
+```
+
+### Offline Queue
+
+```dart
+// Queue failed requests for retry when online
+class OfflineQueue {
+  final HiveInterface hive;
+  late Box<Map> _queueBox;
+
+  Future<void> init() async {
+    _queueBox = await hive.openBox('offline_queue');
+  }
+
+  Future<void> addToQueue(ApiRequest request) async {
+    await _queueBox.add({
+      'endpoint': request.endpoint,
+      'method': request.method,
+      'body': request.body,
+      'timestamp': DateTime.now().toIso8601String(),
+    });
+  }
+
+  Future<void> processQueue() async {
+    final requests = _queueBox.values.toList();
+
+    for (var i = 0; i < requests.length; i++) {
+      try {
+        await _executeRequest(requests[i]);
+        await _queueBox.deleteAt(i);
+      } catch (e) {
+        // Keep in queue for next retry
+      }
+    }
+  }
+}
+```
+
+---
+
+## Localization
+
+### Setup
+
+```dart
+// l10n.yaml
+arb-dir: lib/l10n
+template-arb-file: app_en.arb
+output-localization-file: app_localizations.dart
+
+// lib/l10n/app_vi.arb (Vietnamese)
+{
+  "@@locale": "vi",
+  "appTitle": "Worker App",
+  "login": "Đăng nhập",
+  "phone": "Số điện thoại",
+  "enterPhone": "Nhập số điện thoại",
+  "continue": "Tiếp tục",
+  "verifyOTP": "Xác thực OTP",
+  "enterOTP": "Nhập mã OTP 6 số",
+  "resendOTP": "Gửi lại mã",
+  "home": "Trang chủ",
+  "products": "Sản phẩm",
+  "loyalty": "Hội viên",
+  "account": "Tài khoản",
+  "points": "Điểm",
+  "cart": "Giỏ hàng",
+  "checkout": "Thanh toán",
+  "orders": "Đơn hàng",
+  "projects": "Công trình",
+  "quotes": "Báo giá",
+  "myGifts": "Quà của tôi",
+  "referral": "Giới thiệu bạn bè",
+  "pointsHistory": "Lịch sử điểm"
+}
+
+// lib/l10n/app_en.arb (English)
+{
+  "@@locale": "en",
+  "appTitle": "Worker App",
+  "login": "Login",
+  "phone": "Phone Number",
+  "enterPhone": "Enter phone number",
+  "continue": "Continue",
+  ...
+}
+```
+
+### Usage
+
+```dart
+class LoginPage extends ConsumerWidget {
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final l10n = AppLocalizations.of(context)!;
+
+    return Scaffold(
+      appBar: AppBar(
+        title: Text(l10n.login),
+      ),
+      body: Column(
+        children: [
+          TextField(
+            decoration: InputDecoration(
+              labelText: l10n.phone,
+              hintText: l10n.enterPhone,
+            ),
+          ),
+          ElevatedButton(
+            onPressed: () {},
+            child: Text(l10n.continue),
+          ),
+        ],
+      ),
+    );
+  }
+}
+```
+
+---
+
+## Deployment
+
+### Android
+
+```gradle
+// android/app/build.gradle
+android {
+    compileSdkVersion 34
+
+    defaultConfig {
+        applicationId "com.eurotile.worker"
+        minSdkVersion 21
+        targetSdkVersion 34
+        versionCode 1
+        versionName "1.0.0"
+    }
+
+    signingConfigs {
+        release {
+            storeFile file(RELEASE_STORE_FILE)
+            storePassword RELEASE_STORE_PASSWORD
+            keyAlias RELEASE_KEY_ALIAS
+            keyPassword RELEASE_KEY_PASSWORD
+        }
+    }
+
+    buildTypes {
+        release {
+            signingConfig signingConfigs.release
+            minifyEnabled true
+            shrinkResources true
+            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
+        }
+    }
+}
+```
+
+### iOS
+
+```ruby
+# ios/Podfile
+platform :ios, '13.0'
+
+post_install do |installer|
+  installer.pods_project.targets.each do |target|
+    flutter_additional_ios_build_settings(target)
+    target.build_configurations.each do |config|
+      config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = '13.0'
+    end
+  end
+end
+```
+
+---
+
+## Quick Reference
+
+### Key Requirements for All Code
+
+- ✅ Black back arrow with explicit color
+- ✅ Black text title with TextStyle
+- ✅ Left-aligned title (`centerTitle: false`)
+- ✅ White background (`AppColors.white`)
+- ✅ Use `AppBarSpecs.elevation` (not hardcoded values)
+- ✅ Always add `SizedBox(width: AppSpacing.sm)` after actions
+- ✅ For SliverAppBar, add `pinned: true` property
+- ✅ Use `Box<dynamic>` for Hive boxes with `.whereType<T>()` filtering
+- ✅ Clean architecture (data/domain/presentation)
+- ✅ Riverpod state management
+- ✅ Hive for local persistence
+- ✅ Material 3 design system
+- ✅ Vietnamese localization
+- ✅ CachedNetworkImage for all remote images
+- ✅ Proper error handling
+- ✅ Loading states (CircularProgressIndicator)
+- ✅ Empty states with helpful messages