fix

.vscode/settings.json

@@ -0,0 +1,11 @@
+{
+    "files.watcherExclude": {
+        "**/.git/objects/**": true,
+        "**/.git/subtree-cache/**": true,
+        "**/.hg/store/**": true,
+        "**/.dart_tool": true,
+        "**/.git/**": true,
+        "**/node_modules/**": true,
+        "**/.vscode/**": true
+    }
+}

lib/app.dart

@@ -1,15 +1,11 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'core/router/app_router.dart';
 import 'core/theme/app_theme.dart';
-import 'features/auth/presentation/presentation.dart';
-import 'features/home/presentation/pages/home_page.dart';
-import 'features/products/presentation/pages/products_page.dart';
-import 'features/categories/presentation/pages/categories_page.dart';
-import 'features/settings/presentation/pages/settings_page.dart';
+import 'features/auth/presentation/providers/auth_provider.dart';
 import 'features/settings/presentation/providers/theme_provider.dart';
-import 'shared/widgets/app_bottom_nav.dart';
 
-/// Root application widget with authentication wrapper
+/// Root application widget with go_router integration
 class RetailApp extends ConsumerStatefulWidget {
   const RetailApp({super.key});
 
@@ -32,54 +28,15 @@ class _RetailAppState extends ConsumerState<RetailApp> {
   @override
   Widget build(BuildContext context) {
     final themeMode = ref.watch(themeModeFromThemeProvider);
+    final router = ref.watch(routerProvider);
 
-    return MaterialApp(
+    return MaterialApp.router(
       title: 'Retail POS',
       debugShowCheckedModeBanner: false,
       theme: AppTheme.lightTheme,
       darkTheme: AppTheme.darkTheme,
       themeMode: themeMode,
-      // Wrap the home with AuthWrapper to require login
-      home: const AuthWrapper(
-        child: MainScreen(),
-      ),
-    );
-  }
-}
-
-/// Main screen with bottom navigation (only accessible after login)
-class MainScreen extends ConsumerStatefulWidget {
-  const MainScreen({super.key});
-
-  @override
-  ConsumerState<MainScreen> createState() => _MainScreenState();
-}
-
-class _MainScreenState extends ConsumerState<MainScreen> {
-  int _currentIndex = 0;
-
-  final List<Widget> _pages = const [
-    HomePage(),
-    ProductsPage(),
-    CategoriesPage(),
-    SettingsPage(),
-  ];
-
-  @override
-  Widget build(BuildContext context) {
-    return Scaffold(
-      body: IndexedStack(
-        index: _currentIndex,
-        children: _pages,
-      ),
-      bottomNavigationBar: AppBottomNav(
-        currentIndex: _currentIndex,
-        onTap: (index) {
-          setState(() {
-            _currentIndex = index;
-          });
-        },
-      ),
+      routerConfig: router,
     );
   }
 }

lib/core/router/app_router.dart

@@ -0,0 +1,156 @@
+import 'package:go_router/go_router.dart';
+import 'package:riverpod_annotation/riverpod_annotation.dart';
+import '../../features/auth/presentation/pages/login_page.dart';
+import '../../features/auth/presentation/pages/register_page.dart';
+import '../../features/auth/presentation/providers/auth_provider.dart';
+import '../../features/auth/presentation/widgets/splash_screen.dart';
+import '../../features/categories/presentation/pages/categories_page.dart';
+import '../../features/categories/presentation/pages/category_detail_page.dart';
+import '../../features/home/presentation/pages/home_page.dart';
+import '../../features/products/presentation/pages/batch_update_page.dart';
+import '../../features/products/presentation/pages/product_detail_page.dart';
+import '../../features/products/presentation/pages/products_page.dart';
+import '../../features/settings/presentation/pages/settings_page.dart';
+import '../../shared/widgets/app_bottom_nav_shell.dart';
+
+part 'app_router.g.dart';
+
+/// Router configuration provider
+@Riverpod(keepAlive: true)
+GoRouter router(Ref ref) {
+  final authState = ref.watch(authProvider);
+
+  return GoRouter(
+    initialLocation: '/',
+    debugLogDiagnostics: true,
+    redirect: (context, state) {
+      final isAuthenticated = authState.isAuthenticated;
+      final isLoading = authState.isLoading && authState.user == null;
+      final isGoingToAuth = state.matchedLocation == '/login' ||
+          state.matchedLocation == '/register';
+
+      // Show splash screen while loading
+      if (isLoading) {
+        return '/splash';
+      }
+
+      // Redirect to login if not authenticated and not already going to auth pages
+      if (!isAuthenticated && !isGoingToAuth && state.matchedLocation != '/splash') {
+        return '/login';
+      }
+
+      // Redirect to home if authenticated and going to auth pages
+      if (isAuthenticated && isGoingToAuth) {
+        return '/';
+      }
+
+      return null;
+    },
+    routes: [
+      // Splash screen
+      GoRoute(
+        path: '/splash',
+        name: 'splash',
+        builder: (context, state) => const SplashScreen(),
+      ),
+
+      // Auth routes
+      GoRoute(
+        path: '/login',
+        name: 'login',
+        builder: (context, state) => const LoginPage(),
+      ),
+      GoRoute(
+        path: '/register',
+        name: 'register',
+        builder: (context, state) => const RegisterPage(),
+      ),
+
+      // Main shell with bottom navigation
+      ShellRoute(
+        builder: (context, state, child) {
+          return AppBottomNavShell(child: child);
+        },
+        routes: [
+          // Home tab
+          GoRoute(
+            path: '/',
+            name: 'home',
+            pageBuilder: (context, state) => NoTransitionPage(
+              key: state.pageKey,
+              child: const HomePage(),
+            ),
+          ),
+
+          // Products tab
+          GoRoute(
+            path: '/products',
+            name: 'products',
+            pageBuilder: (context, state) => NoTransitionPage(
+              key: state.pageKey,
+              child: const ProductsPage(),
+            ),
+            routes: [
+              // Product detail
+              GoRoute(
+                path: ':productId',
+                name: 'product-detail',
+                builder: (context, state) {
+                  final productId = state.pathParameters['productId']!;
+                  return ProductDetailPage(productId: productId);
+                },
+              ),
+              // Batch update
+              GoRoute(
+                path: 'batch-update',
+                name: 'batch-update',
+                builder: (context, state) {
+                  // Get selected products from extra parameter
+                  final selectedProducts = state.extra as List<dynamic>?;
+                  if (selectedProducts == null) {
+                    // If no products provided, return to products page
+                    return const ProductsPage();
+                  }
+                  return BatchUpdatePage(
+                    selectedProducts: selectedProducts.cast(),
+                  );
+                },
+              ),
+            ],
+          ),
+
+          // Categories tab
+          GoRoute(
+            path: '/categories',
+            name: 'categories',
+            pageBuilder: (context, state) => NoTransitionPage(
+              key: state.pageKey,
+              child: const CategoriesPage(),
+            ),
+            routes: [
+              // Category detail
+              GoRoute(
+                path: ':categoryId',
+                name: 'category-detail',
+                builder: (context, state) {
+                  final categoryId = state.pathParameters['categoryId']!;
+                  return CategoryDetailPage(categoryId: categoryId);
+                },
+              ),
+            ],
+          ),
+
+          // Settings tab
+          GoRoute(
+            path: '/settings',
+            name: 'settings',
+            pageBuilder: (context, state) => NoTransitionPage(
+              key: state.pageKey,
+              child: const SettingsPage(),
+            ),
+          ),
+        ],
+      ),
+    ],
+  );
+}

lib/core/router/app_router.g.dart

@@ -0,0 +1,55 @@
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+part of 'app_router.dart';
+
+// **************************************************************************
+// RiverpodGenerator
+// **************************************************************************
+
+// GENERATED CODE - DO NOT MODIFY BY HAND
+// ignore_for_file: type=lint, type=warning
+/// Router configuration provider
+
+@ProviderFor(router)
+const routerProvider = RouterProvider._();
+
+/// Router configuration provider
+
+final class RouterProvider
+    extends $FunctionalProvider<GoRouter, GoRouter, GoRouter>
+    with $Provider<GoRouter> {
+  /// Router configuration provider
+  const RouterProvider._()
+    : super(
+        from: null,
+        argument: null,
+        retry: null,
+        name: r'routerProvider',
+        isAutoDispose: false,
+        dependencies: null,
+        $allTransitiveDependencies: null,
+      );
+
+  @override
+  String debugGetCreateSourceHash() => _$routerHash();
+
+  @$internal
+  @override
+  $ProviderElement<GoRouter> $createElement($ProviderPointer pointer) =>
+      $ProviderElement(pointer);
+
+  @override
+  GoRouter create(Ref ref) {
+    return router(ref);
+  }
+
+  /// {@macro riverpod.override_with_value}
+  Override overrideWithValue(GoRouter value) {
+    return $ProviderOverride(
+      origin: this,
+      providerOverride: $SyncValueProvider<GoRouter>(value),
+    );
+  }
+}
+
+String _$routerHash() => r'3c7108371f8529a70e1e479728e8da132246bab4';

lib/features/auth/presentation/pages/login_page.dart

@@ -1,9 +1,9 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:go_router/go_router.dart';
 import '../providers/auth_provider.dart';
 import '../widgets/widgets.dart';
 import '../utils/validators.dart';
-import 'register_page.dart';
 
 /// Login page with email and password authentication
 class LoginPage extends ConsumerStatefulWidget {
@@ -66,11 +66,7 @@ class _LoginPageState extends ConsumerState<LoginPage> {
   }
 
   void _navigateToRegister() {
-    Navigator.of(context).push(
-      MaterialPageRoute(
-        builder: (context) => const RegisterPage(),
-      ),
-    );
+    context.push('/register');
   }
 
   void _handleForgotPassword() {

lib/features/auth/presentation/pages/register_page.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:go_router/go_router.dart';
 import '../providers/auth_provider.dart';
 import '../widgets/widgets.dart';
 import '../utils/validators.dart';
@@ -90,7 +91,7 @@ class _RegisterPageState extends ConsumerState<RegisterPage> {
   }
 
   void _navigateBackToLogin() {
-    Navigator.of(context).pop();
+    context.pop();
   }
 
   @override

lib/features/auth/presentation/providers/auth_provider.dart

@@ -64,9 +64,9 @@ class AuthState {
 class Auth extends _$Auth {
   @override
   AuthState build() {
-    // Don't call async operations in build
+    // Start with loading state to show splash screen
     // Use a separate method to initialize auth state
-    return const AuthState();
+    return const AuthState(isLoading: true);
   }
 
   AuthRepository get _repository => ref.read(authRepositoryProvider);
@@ -74,7 +74,9 @@ class Auth extends _$Auth {
   /// Initialize auth state - call this on app start
   Future<void> initialize() async {
     print('🚀 Initializing auth state...');
-    state = state.copyWith(isLoading: true);
+
+    // Minimum loading time for smooth UX (prevent flashing)
+    final minimumLoadingTime = Future.delayed(const Duration(milliseconds: 800));
 
     final isAuthenticated = await _repository.isAuthenticated();
     print('🚀 isAuthenticated result: $isAuthenticated');
@@ -83,6 +85,10 @@ class Auth extends _$Auth {
       print('🚀 Token found, fetching user profile...');
       // Get user profile
       final result = await _repository.getProfile();
+
+      // Wait for minimum loading time to complete
+      await minimumLoadingTime;
+
       result.fold(
         (failure) {
           print('❌ Failed to get profile: ${failure.message}');
@@ -103,6 +109,10 @@ class Auth extends _$Auth {
       );
     } else {
       print('❌ No token found, user needs to login');
+
+      // Wait for minimum loading time even when not authenticated
+      await minimumLoadingTime;
+
       state = const AuthState(
         isAuthenticated: false,
         isLoading: false,

lib/features/auth/presentation/providers/auth_provider.g.dart

@@ -142,7 +142,7 @@ final class AuthProvider extends $NotifierProvider<Auth, AuthState> {
   }
 }
 
-String _$authHash() => r'73c9e7b70799eba2904eb6fc65454332d4146a33';
+String _$authHash() => r'24ad5a5313febf1a3ac2550adaf19f34098a8f7c';
 
 /// Auth state notifier provider
 

lib/features/auth/presentation/widgets/auth_wrapper.dart

@@ -2,6 +2,7 @@ import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import '../providers/auth_provider.dart';
 import '../pages/login_page.dart';
+import 'splash_screen.dart';
 
 /// Wrapper widget that checks authentication status
 /// Shows login page if not authenticated, otherwise shows child widget
@@ -17,20 +18,26 @@ class AuthWrapper extends ConsumerWidget {
   Widget build(BuildContext context, WidgetRef ref) {
     final authState = ref.watch(authProvider);
     print('AuthWrapper build: isAuthenticated=${authState.isAuthenticated}, isLoading=${authState.isLoading}');
-    // Show loading indicator while checking auth status
+
+    // Show splash screen while checking auth status
     if (authState.isLoading && authState.user == null) {
-      return const Scaffold(
-        body: Center(
-          child: CircularProgressIndicator(),
+      return const SplashScreen();
+    }
+
+    // Smooth fade transition between screens
+    return AnimatedSwitcher(
+      duration: const Duration(milliseconds: 400),
+      switchInCurve: Curves.easeInOut,
+      switchOutCurve: Curves.easeInOut,
+      child: authState.isAuthenticated
+          ? KeyedSubtree(
+              key: const ValueKey('main_app'),
+              child: child,
+            )
+          : const KeyedSubtree(
+              key: ValueKey('login_page'),
+              child: LoginPage(),
             ),
     );
   }
-
-    // Show child widget if authenticated, otherwise show login page
-    if (authState.isAuthenticated) {
-      return child;
-    } else {
-      return const LoginPage();
-    }
-  }
 }

lib/features/auth/presentation/widgets/splash_screen.dart

@@ -0,0 +1,135 @@
+import 'package:flutter/material.dart';
+
+/// Splash screen shown while checking authentication status
+class SplashScreen extends StatefulWidget {
+  const SplashScreen({super.key});
+
+  @override
+  State<SplashScreen> createState() => _SplashScreenState();
+}
+
+class _SplashScreenState extends State<SplashScreen>
+    with SingleTickerProviderStateMixin {
+  late AnimationController _controller;
+  late Animation<double> _fadeAnimation;
+  late Animation<double> _scaleAnimation;
+
+  @override
+  void initState() {
+    super.initState();
+    _controller = AnimationController(
+      duration: const Duration(milliseconds: 800),
+      vsync: this,
+    );
+
+    _fadeAnimation = Tween<double>(begin: 0.0, end: 1.0).animate(
+      CurvedAnimation(
+        parent: _controller,
+        curve: Curves.easeIn,
+      ),
+    );
+
+    _scaleAnimation = Tween<double>(begin: 0.8, end: 1.0).animate(
+      CurvedAnimation(
+        parent: _controller,
+        curve: Curves.easeOutBack,
+      ),
+    );
+
+    _controller.forward();
+  }
+
+  @override
+  void dispose() {
+    _controller.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+
+    return Scaffold(
+      backgroundColor: theme.colorScheme.primary,
+      body: SafeArea(
+        child: Center(
+          child: FadeTransition(
+            opacity: _fadeAnimation,
+            child: ScaleTransition(
+              scale: _scaleAnimation,
+              child: Column(
+                mainAxisAlignment: MainAxisAlignment.center,
+                children: [
+                  // App Icon/Logo
+                  Container(
+                    width: 120,
+                    height: 120,
+                    decoration: BoxDecoration(
+                      color: Colors.white,
+                      borderRadius: BorderRadius.circular(24),
+                      boxShadow: [
+                        BoxShadow(
+                          color: Colors.black.withOpacity(0.2),
+                          blurRadius: 20,
+                          offset: const Offset(0, 10),
+                        ),
+                      ],
+                    ),
+                    child: Icon(
+                      Icons.point_of_sale_rounded,
+                      size: 64,
+                      color: theme.colorScheme.primary,
+                    ),
+                  ),
+                  const SizedBox(height: 32),
+
+                  // App Name
+                  Text(
+                    'Retail POS',
+                    style: theme.textTheme.headlineMedium?.copyWith(
+                      color: Colors.white,
+                      fontWeight: FontWeight.bold,
+                      letterSpacing: 1.2,
+                    ),
+                  ),
+                  const SizedBox(height: 8),
+
+                  // Subtitle
+                  Text(
+                    'Point of Sale System',
+                    style: theme.textTheme.bodyLarge?.copyWith(
+                      color: Colors.white.withOpacity(0.9),
+                      letterSpacing: 0.5,
+                    ),
+                  ),
+                  const SizedBox(height: 48),
+
+                  // Loading Indicator
+                  SizedBox(
+                    width: 40,
+                    height: 40,
+                    child: CircularProgressIndicator(
+                      strokeWidth: 3,
+                      valueColor: AlwaysStoppedAnimation<Color>(
+                        Colors.white.withOpacity(0.9),
+                      ),
+                    ),
+                  ),
+                  const SizedBox(height: 16),
+
+                  // Loading Text
+                  Text(
+                    'Loading...',
+                    style: theme.textTheme.bodyMedium?.copyWith(
+                      color: Colors.white.withOpacity(0.8),
+                    ),
+                  ),
+                ],
+              ),
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+}

lib/features/categories/presentation/pages/category_detail_page.dart

@@ -1,6 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import '../../domain/entities/category.dart';
+import '../providers/categories_provider.dart';
 import '../../../products/presentation/providers/products_provider.dart';
 import '../../../products/presentation/widgets/product_card.dart';
 import '../../../products/presentation/widgets/product_list_item.dart';
@@ -10,11 +11,11 @@ enum ViewMode { grid, list }
 
 /// Category detail page showing products in the category
 class CategoryDetailPage extends ConsumerStatefulWidget {
-  final Category category;
+  final String categoryId;
 
   const CategoryDetailPage({
     super.key,
-    required this.category,
+    required this.categoryId,
   });
 
   @override
@@ -26,11 +27,63 @@ class _CategoryDetailPageState extends ConsumerState<CategoryDetailPage> {
 
   @override
   Widget build(BuildContext context) {
+    final categoriesAsync = ref.watch(categoriesProvider);
     final productsAsync = ref.watch(productsProvider);
 
+    return categoriesAsync.when(
+      data: (categories) {
+        // Find the category by ID
+        Category? category;
+        try {
+          category = categories.firstWhere((c) => c.id == widget.categoryId);
+        } catch (e) {
+          // Category not found
+          category = null;
+        }
+
+        // Handle category not found
+        if (category == null) {
+          return Scaffold(
+            appBar: AppBar(
+              title: const Text('Category Not Found'),
+            ),
+            body: Center(
+              child: Column(
+                mainAxisAlignment: MainAxisAlignment.center,
+                children: [
+                  Icon(
+                    Icons.error_outline,
+                    size: 64,
+                    color: Theme.of(context).colorScheme.error,
+                  ),
+                  const SizedBox(height: 16),
+                  Text(
+                    'Category not found',
+                    style: Theme.of(context).textTheme.titleMedium,
+                  ),
+                  const SizedBox(height: 8),
+                  Text(
+                    'The category you are looking for does not exist',
+                    style: Theme.of(context).textTheme.bodySmall,
+                    textAlign: TextAlign.center,
+                  ),
+                  const SizedBox(height: 16),
+                  FilledButton.icon(
+                    onPressed: () {
+                      Navigator.of(context).pop();
+                    },
+                    icon: const Icon(Icons.arrow_back),
+                    label: const Text('Go Back'),
+                  ),
+                ],
+              ),
+            ),
+          );
+        }
+
         return Scaffold(
           appBar: AppBar(
-        title: Text(widget.category.name),
+            title: Text(category.name),
             actions: [
               // View mode toggle
               IconButton(
@@ -55,7 +108,7 @@ class _CategoryDetailPageState extends ConsumerState<CategoryDetailPage> {
             data: (products) {
               // Filter products by category
               final categoryProducts = products
-              .where((product) => product.categoryId == widget.category.id)
+                  .where((product) => product.categoryId == category!.id)
                   .toList();
 
               if (categoryProducts.isEmpty) {
@@ -132,6 +185,52 @@ class _CategoryDetailPageState extends ConsumerState<CategoryDetailPage> {
             ),
           ),
         );
+      },
+      loading: () => Scaffold(
+        appBar: AppBar(
+          title: const Text('Loading...'),
+        ),
+        body: const Center(
+          child: CircularProgressIndicator(),
+        ),
+      ),
+      error: (error, stack) => Scaffold(
+        appBar: AppBar(
+          title: const Text('Error'),
+        ),
+        body: Center(
+          child: Column(
+            mainAxisAlignment: MainAxisAlignment.center,
+            children: [
+              Icon(
+                Icons.error_outline,
+                size: 64,
+                color: Theme.of(context).colorScheme.error,
+              ),
+              const SizedBox(height: 16),
+              Text(
+                'Error loading category',
+                style: Theme.of(context).textTheme.titleMedium,
+              ),
+              const SizedBox(height: 8),
+              Text(
+                error.toString(),
+                style: Theme.of(context).textTheme.bodySmall,
+                textAlign: TextAlign.center,
+              ),
+              const SizedBox(height: 16),
+              FilledButton.icon(
+                onPressed: () {
+                  ref.invalidate(categoriesProvider);
+                },
+                icon: const Icon(Icons.refresh),
+                label: const Text('Retry'),
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
   }
 
   /// Build grid view

lib/features/categories/presentation/providers/categories_provider.dart

@@ -6,7 +6,8 @@ import '../../../../core/providers/providers.dart';
 part 'categories_provider.g.dart';
 
 /// Provider for categories list with online-first approach
-@riverpod
+/// keepAlive ensures data persists when switching tabs
+@Riverpod(keepAlive: true)
 class Categories extends _$Categories {
   @override
   Future<List<Category>> build() async {

lib/features/categories/presentation/providers/categories_provider.g.dart

@@ -9,21 +9,24 @@ part of 'categories_provider.dart';
 // GENERATED CODE - DO NOT MODIFY BY HAND
 // ignore_for_file: type=lint, type=warning
 /// Provider for categories list with online-first approach
+/// keepAlive ensures data persists when switching tabs
 
 @ProviderFor(Categories)
 const categoriesProvider = CategoriesProvider._();
 
 /// Provider for categories list with online-first approach
+/// keepAlive ensures data persists when switching tabs
 final class CategoriesProvider
     extends $AsyncNotifierProvider<Categories, List<Category>> {
   /// Provider for categories list with online-first approach
+  /// keepAlive ensures data persists when switching tabs
   const CategoriesProvider._()
     : super(
         from: null,
         argument: null,
         retry: null,
         name: r'categoriesProvider',
-        isAutoDispose: true,
+        isAutoDispose: false,
         dependencies: null,
         $allTransitiveDependencies: null,
       );
@@ -36,9 +39,10 @@ final class CategoriesProvider
   Categories create() => Categories();
 }
 
-String _$categoriesHash() => r'33c33b08f8926e5bbbd112285591c74a3ff0f61c';
+String _$categoriesHash() => r'c26eb4b4a76ce796eb65b7843a390805528dec4a';
 
 /// Provider for categories list with online-first approach
+/// keepAlive ensures data persists when switching tabs
 
 abstract class _$Categories extends $AsyncNotifier<List<Category>> {
   FutureOr<List<Category>> build();

lib/features/categories/presentation/widgets/category_card.dart

@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
+import 'package:go_router/go_router.dart';
 import '../../domain/entities/category.dart';
-import '../pages/category_detail_page.dart';
 
 /// Category card widget
 class CategoryCard extends StatelessWidget {
@@ -22,12 +22,7 @@ class CategoryCard extends StatelessWidget {
       child: InkWell(
         onTap: () {
           // Navigate to category detail page
-          Navigator.push(
-            context,
-            MaterialPageRoute(
-              builder: (context) => CategoryDetailPage(category: category),
-            ),
-          );
+          context.push('/categories/${category.id}');
         },
         child: Padding(
           padding: const EdgeInsets.all(16.0),

lib/features/products/presentation/pages/batch_update_page.dart

@@ -1,6 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:go_router/go_router.dart';
 import '../../domain/entities/product.dart';
 import '../../data/models/product_model.dart';
 import '../providers/products_provider.dart';
@@ -139,7 +140,7 @@ class _BatchUpdatePageState extends ConsumerState<BatchUpdatePage> {
                   children: [
                     Expanded(
                       child: OutlinedButton(
-                        onPressed: _isLoading ? null : () => Navigator.pop(context),
+                        onPressed: _isLoading ? null : () => context.pop(),
                         child: const Text('Cancel'),
                       ),
                     ),
@@ -327,7 +328,7 @@ class _BatchUpdatePageState extends ConsumerState<BatchUpdatePage> {
       ref.invalidate(productsProvider);
 
       if (mounted) {
-        Navigator.pop(context);
+        context.pop();
         ScaffoldMessenger.of(context).showSnackBar(
           SnackBar(
             content: Text(

lib/features/products/presentation/pages/product_detail_page.dart

@@ -3,33 +3,66 @@ import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:cached_network_image/cached_network_image.dart';
 import 'package:intl/intl.dart';
 import '../../domain/entities/product.dart';
+import '../providers/products_provider.dart';
 import '../../../categories/presentation/providers/categories_provider.dart';
 import '../../../../shared/widgets/price_display.dart';
 
 /// Product detail page showing full product information
 class ProductDetailPage extends ConsumerWidget {
-  final Product product;
+  final String productId;
 
   const ProductDetailPage({
     super.key,
-    required this.product,
+    required this.productId,
   });
 
   @override
   Widget build(BuildContext context, WidgetRef ref) {
+    final productsAsync = ref.watch(productsProvider);
     final categoriesAsync = ref.watch(categoriesProvider);
 
+    return productsAsync.when(
+      data: (products) {
+        // Find the product by ID
+        Product? product;
+        try {
+          product = products.firstWhere((p) => p.id == productId);
+        } catch (e) {
+          // Product not found
+          return Scaffold(
+            appBar: AppBar(title: const Text('Product Not Found')),
+            body: const Center(child: Text('Product not found')),
+          );
+        }
+
         // Find category name
         final categoryName = categoriesAsync.whenOrNull(
           data: (categories) {
+            try {
               final category = categories.firstWhere(
-          (cat) => cat.id == product.categoryId,
-          orElse: () => categories.first,
+                (cat) => cat.id == product!.categoryId,
               );
               return category.name;
+            } catch (e) {
+              return null;
+            }
           },
         );
 
+        return _buildProductDetail(context, product, categoryName);
+      },
+      loading: () => Scaffold(
+        appBar: AppBar(title: const Text('Product Details')),
+        body: const Center(child: CircularProgressIndicator()),
+      ),
+      error: (error, stack) => Scaffold(
+        appBar: AppBar(title: const Text('Error')),
+        body: Center(child: Text('Error: $error')),
+      ),
+    );
+  }
+
+  Widget _buildProductDetail(BuildContext context, Product product, String? categoryName) {
     return Scaffold(
       appBar: AppBar(
         title: const Text('Product Details'),
@@ -48,7 +81,7 @@ class ProductDetailPage extends ConsumerWidget {
           crossAxisAlignment: CrossAxisAlignment.start,
           children: [
             // Product Image
-            _buildProductImage(context),
+            _buildProductImage(context, product),
 
             // Product Info Section
             Padding(
@@ -97,19 +130,19 @@ class ProductDetailPage extends ConsumerWidget {
                   const SizedBox(height: 24),
 
                   // Stock Information
-                  _buildStockSection(context),
+                  _buildStockSection(context, product),
                   const SizedBox(height: 24),
 
                   // Description Section
-                  _buildDescriptionSection(context),
+                  _buildDescriptionSection(context, product),
                   const SizedBox(height: 24),
 
                   // Additional Information
-                  _buildAdditionalInfo(context),
+                  _buildAdditionalInfo(context, product),
                   const SizedBox(height: 24),
 
                   // Action Buttons
-                  _buildActionButtons(context),
+                  _buildActionButtons(context, product),
                 ],
               ),
             ),
@@ -120,7 +153,7 @@ class ProductDetailPage extends ConsumerWidget {
   }
 
   /// Build product image section
-  Widget _buildProductImage(BuildContext context) {
+  Widget _buildProductImage(BuildContext context, Product product) {
     return Hero(
       tag: 'product-${product.id}',
       child: Container(
@@ -154,9 +187,9 @@ class ProductDetailPage extends ConsumerWidget {
   }
 
   /// Build stock information section
-  Widget _buildStockSection(BuildContext context) {
-    final stockColor = _getStockColor(context);
-    final stockStatus = _getStockStatus();
+  Widget _buildStockSection(BuildContext context, Product product) {
+    final stockColor = _getStockColor(context, product);
+    final stockStatus = _getStockStatus(product);
 
     return Card(
       child: Padding(
@@ -245,7 +278,7 @@ class ProductDetailPage extends ConsumerWidget {
   }
 
   /// Build description section
-  Widget _buildDescriptionSection(BuildContext context) {
+  Widget _buildDescriptionSection(BuildContext context, Product product) {
     if (product.description == null || product.description!.isEmpty) {
       return const SizedBox.shrink();
     }
@@ -269,7 +302,7 @@ class ProductDetailPage extends ConsumerWidget {
   }
 
   /// Build additional information section
-  Widget _buildAdditionalInfo(BuildContext context) {
+  Widget _buildAdditionalInfo(BuildContext context, Product product) {
     final dateFormat = DateFormat('MMM dd, yyyy');
 
     return Card(
@@ -355,7 +388,7 @@ class ProductDetailPage extends ConsumerWidget {
   }
 
   /// Build action buttons
-  Widget _buildActionButtons(BuildContext context) {
+  Widget _buildActionButtons(BuildContext context, Product product) {
     return Column(
       children: [
         // Add to Cart Button
@@ -400,7 +433,7 @@ class ProductDetailPage extends ConsumerWidget {
   }
 
   /// Get stock color based on quantity
-  Color _getStockColor(BuildContext context) {
+  Color _getStockColor(BuildContext context, Product product) {
     if (product.stockQuantity == 0) {
       return Colors.red;
     } else if (product.stockQuantity < 5) {
@@ -411,7 +444,7 @@ class ProductDetailPage extends ConsumerWidget {
   }
 
   /// Get stock status text
-  String _getStockStatus() {
+  String _getStockStatus(Product product) {
     if (product.stockQuantity == 0) {
       return 'Out of Stock';
     } else if (product.stockQuantity < 5) {

lib/features/products/presentation/pages/products_page.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:go_router/go_router.dart';
 import '../widgets/product_grid.dart';
 import '../widgets/product_search_bar.dart';
 import '../widgets/product_list_item.dart';
@@ -99,13 +100,9 @@ class _ProductsPageState extends ConsumerState<ProductsPage> {
                       final selectedProducts = filteredProducts
                           .where((p) => _selectedProductIds.contains(p.id))
                           .toList();
-                      Navigator.push(
-                        context,
-                        MaterialPageRoute(
-                          builder: (context) => BatchUpdatePage(
-                            selectedProducts: selectedProducts,
-                          ),
-                        ),
+                      context.push(
+                        '/products/batch-update',
+                        extra: selectedProducts,
                       ).then((_) {
                         setState(() {
                           _isSelectionMode = false;

lib/features/products/presentation/providers/products_provider.dart

@@ -6,7 +6,8 @@ import '../../../../core/providers/providers.dart';
 part 'products_provider.g.dart';
 
 /// Provider for products list with online-first approach
-@riverpod
+/// keepAlive ensures data persists when switching tabs
+@Riverpod(keepAlive: true)
 class Products extends _$Products {
   @override
   Future<List<Product>> build() async {

lib/features/products/presentation/providers/products_provider.g.dart

@@ -9,21 +9,24 @@ part of 'products_provider.dart';
 // GENERATED CODE - DO NOT MODIFY BY HAND
 // ignore_for_file: type=lint, type=warning
 /// Provider for products list with online-first approach
+/// keepAlive ensures data persists when switching tabs
 
 @ProviderFor(Products)
 const productsProvider = ProductsProvider._();
 
 /// Provider for products list with online-first approach
+/// keepAlive ensures data persists when switching tabs
 final class ProductsProvider
     extends $AsyncNotifierProvider<Products, List<Product>> {
   /// Provider for products list with online-first approach
+  /// keepAlive ensures data persists when switching tabs
   const ProductsProvider._()
     : super(
         from: null,
         argument: null,
         retry: null,
         name: r'productsProvider',
-        isAutoDispose: true,
+        isAutoDispose: false,
         dependencies: null,
         $allTransitiveDependencies: null,
       );
@@ -36,9 +39,10 @@ final class ProductsProvider
   Products create() => Products();
 }
 
-String _$productsHash() => r'0ff8c2de46bb4b1e29678cc811ec121c9fb4c8eb';
+String _$productsHash() => r'1fa5341d86a35a3b3d6666da88e0c5db757cdcdb';
 
 /// Provider for products list with online-first approach
+/// keepAlive ensures data persists when switching tabs
 
 abstract class _$Products extends $AsyncNotifier<List<Product>> {
   FutureOr<List<Product>> build();

lib/features/products/presentation/widgets/product_card.dart

@@ -1,7 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:cached_network_image/cached_network_image.dart';
+import 'package:go_router/go_router.dart';
 import '../../domain/entities/product.dart';
-import '../pages/product_detail_page.dart';
 import '../../../../shared/widgets/price_display.dart';
 
 /// Product card widget
@@ -20,12 +20,7 @@ class ProductCard extends StatelessWidget {
       child: InkWell(
         onTap: () {
           // Navigate to product detail page
-          Navigator.push(
-            context,
-            MaterialPageRoute(
-              builder: (context) => ProductDetailPage(product: product),
-            ),
-          );
+          context.push('/products/${product.id}');
         },
         child: Column(
           crossAxisAlignment: CrossAxisAlignment.start,

lib/features/products/presentation/widgets/product_list_item.dart

@@ -1,7 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:cached_network_image/cached_network_image.dart';
+import 'package:go_router/go_router.dart';
 import '../../domain/entities/product.dart';
-import '../pages/product_detail_page.dart';
 import '../../../../shared/widgets/price_display.dart';
 
 /// Product list item widget for list view
@@ -23,12 +23,7 @@ class ProductListItem extends StatelessWidget {
         onTap: onTap ??
             () {
               // Navigate to product detail page
-              Navigator.push(
-                context,
-                MaterialPageRoute(
-                  builder: (context) => ProductDetailPage(product: product),
-                ),
-              );
+              context.push('/products/${product.id}');
             },
         child: Padding(
           padding: const EdgeInsets.all(12.0),

lib/features/settings/presentation/pages/settings_page.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:go_router/go_router.dart';
 import '../providers/settings_provider.dart';
 import '../../../auth/presentation/providers/auth_provider.dart';
 import '../../../../core/constants/app_constants.dart';
@@ -105,11 +106,11 @@ class SettingsPage extends ConsumerWidget {
                                 content: const Text('Are you sure you want to logout?'),
                                 actions: [
                                   TextButton(
-                                    onPressed: () => Navigator.pop(context, false),
+                                    onPressed: () => context.pop(false),
                                     child: const Text('Cancel'),
                                   ),
                                   FilledButton(
-                                    onPressed: () => Navigator.pop(context, true),
+                                    onPressed: () => context.pop(true),
                                     style: FilledButton.styleFrom(
                                       backgroundColor: Theme.of(context).colorScheme.error,
                                     ),
@@ -294,7 +295,7 @@ class SettingsPage extends ConsumerWidget {
               onChanged: (value) {
                 if (value != null) {
                   ref.read(settingsProvider.notifier).updateTheme(value);
-                  Navigator.pop(context);
+                  context.pop();
                 }
               },
             ),
@@ -305,7 +306,7 @@ class SettingsPage extends ConsumerWidget {
               onChanged: (value) {
                 if (value != null) {
                   ref.read(settingsProvider.notifier).updateTheme(value);
-                  Navigator.pop(context);
+                  context.pop();
                 }
               },
             ),
@@ -316,7 +317,7 @@ class SettingsPage extends ConsumerWidget {
               onChanged: (value) {
                 if (value != null) {
                   ref.read(settingsProvider.notifier).updateTheme(value);
-                  Navigator.pop(context);
+                  context.pop();
                 }
               },
             ),
@@ -341,7 +342,7 @@ class SettingsPage extends ConsumerWidget {
               onChanged: (value) {
                 if (value != null) {
                   ref.read(settingsProvider.notifier).updateLanguage(value);
-                  Navigator.pop(context);
+                  context.pop();
                 }
               },
             ),
@@ -352,7 +353,7 @@ class SettingsPage extends ConsumerWidget {
               onChanged: (value) {
                 if (value != null) {
                   ref.read(settingsProvider.notifier).updateLanguage(value);
-                  Navigator.pop(context);
+                  context.pop();
                 }
               },
             ),
@@ -363,7 +364,7 @@ class SettingsPage extends ConsumerWidget {
               onChanged: (value) {
                 if (value != null) {
                   ref.read(settingsProvider.notifier).updateLanguage(value);
-                  Navigator.pop(context);
+                  context.pop();
                 }
               },
             ),
@@ -388,7 +389,7 @@ class SettingsPage extends ConsumerWidget {
               onChanged: (value) {
                 if (value != null) {
                   // TODO: Implement currency update
-                  Navigator.pop(context);
+                  context.pop();
                 }
               },
             ),
@@ -399,7 +400,7 @@ class SettingsPage extends ConsumerWidget {
               onChanged: (value) {
                 if (value != null) {
                   // TODO: Implement currency update
-                  Navigator.pop(context);
+                  context.pop();
                 }
               },
             ),
@@ -410,7 +411,7 @@ class SettingsPage extends ConsumerWidget {
               onChanged: (value) {
                 if (value != null) {
                   // TODO: Implement currency update
-                  Navigator.pop(context);
+                  context.pop();
                 }
               },
             ),
@@ -437,13 +438,13 @@ class SettingsPage extends ConsumerWidget {
         ),
         actions: [
           TextButton(
-            onPressed: () => Navigator.pop(context),
+            onPressed: () => context.pop(),
             child: const Text('Cancel'),
           ),
           FilledButton(
             onPressed: () {
               // TODO: Implement store name update
-              Navigator.pop(context);
+              context.pop();
               ScaffoldMessenger.of(context).showSnackBar(
                 const SnackBar(content: Text('Store name updated')),
               );
@@ -476,13 +477,13 @@ class SettingsPage extends ConsumerWidget {
         ),
         actions: [
           TextButton(
-            onPressed: () => Navigator.pop(context),
+            onPressed: () => context.pop(),
             child: const Text('Cancel'),
           ),
           FilledButton(
             onPressed: () {
               // TODO: Implement tax rate update
-              Navigator.pop(context);
+              context.pop();
               ScaffoldMessenger.of(context).showSnackBar(
                 const SnackBar(content: Text('Tax rate updated')),
               );
@@ -521,7 +522,7 @@ class SettingsPage extends ConsumerWidget {
 
     // Close loading dialog
     if (context.mounted) {
-      Navigator.pop(context);
+      context.pop();
       ScaffoldMessenger.of(context).showSnackBar(
         const SnackBar(content: Text('Data synced successfully')),
       );
@@ -538,12 +539,12 @@ class SettingsPage extends ConsumerWidget {
         ),
         actions: [
           TextButton(
-            onPressed: () => Navigator.pop(context),
+            onPressed: () => context.pop(),
             child: const Text('Cancel'),
           ),
           FilledButton(
             onPressed: () {
-              Navigator.pop(context);
+              context.pop();
               ScaffoldMessenger.of(context).showSnackBar(
                 const SnackBar(content: Text('Cache cleared')),
               );

lib/shared/widgets/app_bottom_nav_shell.dart

@@ -0,0 +1,81 @@
+import 'package:flutter/material.dart';
+import 'package:go_router/go_router.dart';
+
+/// Shell widget that provides bottom navigation for the app
+class AppBottomNavShell extends StatelessWidget {
+  const AppBottomNavShell({
+    super.key,
+    required this.child,
+  });
+
+  final Widget child;
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      body: child,
+      bottomNavigationBar: _AppBottomNavigationBar(),
+    );
+  }
+}
+
+class _AppBottomNavigationBar extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    final location = GoRouterState.of(context).matchedLocation;
+
+    // Determine current index based on location
+    int currentIndex = 0;
+    if (location == '/') {
+      currentIndex = 0;
+    } else if (location.startsWith('/products')) {
+      currentIndex = 1;
+    } else if (location.startsWith('/categories')) {
+      currentIndex = 2;
+    } else if (location.startsWith('/settings')) {
+      currentIndex = 3;
+    }
+
+    return NavigationBar(
+      selectedIndex: currentIndex,
+      onDestinationSelected: (index) {
+        switch (index) {
+          case 0:
+            context.go('/');
+            break;
+          case 1:
+            context.go('/products');
+            break;
+          case 2:
+            context.go('/categories');
+            break;
+          case 3:
+            context.go('/settings');
+            break;
+        }
+      },
+      destinations: const [
+        NavigationDestination(
+          icon: Icon(Icons.point_of_sale_outlined),
+          selectedIcon: Icon(Icons.point_of_sale),
+          label: 'Home',
+        ),
+        NavigationDestination(
+          icon: Icon(Icons.inventory_2_outlined),
+          selectedIcon: Icon(Icons.inventory_2),
+          label: 'Products',
+        ),
+        NavigationDestination(
+          icon: Icon(Icons.category_outlined),
+          selectedIcon: Icon(Icons.category),
+          label: 'Categories',
+        ),
+        NavigationDestination(
+          icon: Icon(Icons.settings_outlined),
+          selectedIcon: Icon(Icons.settings),
+          label: 'Settings',
+        ),
+      ],
+    );
+  }
+}

pubspec.lock

@@ -480,6 +480,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.1.3"
+  go_router:
+    dependency: "direct main"
+    description:
+      name: go_router
+      sha256: f02fd7d2a4dc512fec615529824fdd217fecb3a3d3de68360293a551f21634b3
+      url: "https://pub.dev"
+    source: hosted
+    version: "14.8.1"
   graphs:
     dependency: transitive
     description:

pubspec.yaml

@@ -49,6 +49,9 @@ dependencies:
   flutter_riverpod: ^3.0.0
   riverpod_annotation: ^3.0.0
 
+  # Routing
+  go_router: ^14.6.2
+
   # Network
   dio: ^5.7.0
   connectivity_plus: ^6.1.1