flutter_ecommerce_portal/lib/screens/home_screen.dart

import 'package:flutter/material.dart';
import 'package:provider/provider.dart';

import '../services/auth_service.dart';
import '../services/cart_service.dart';
import '../services/product_repository.dart';
import '../widgets/product_card.dart';
import 'cart_screen.dart';
import 'product_detail_screen.dart';
import 'profile_screen.dart';

class HomeScreen extends StatelessWidget {
  const HomeScreen({super.key});

  @override
  Widget build(BuildContext context) {
    final cartCount = context.watch<CartService>().totalItems;

    return Scaffold(
      appBar: AppBar(
        title: const Text('E-Commerce Portal'),
        actions: [
          IconButton(
            tooltip: 'Profile',
            onPressed: () {
              Navigator.of(context).push(
                MaterialPageRoute(builder: (_) => const ProfileScreen()),
              );
            },
            icon: const Icon(Icons.person),
          ),
          Stack(
            children: [
              IconButton(
                tooltip: 'Cart',
                onPressed: () {
                  Navigator.of(context).push(
                    MaterialPageRoute(builder: (_) => const CartScreen()),
                  );
                },
                icon: const Icon(Icons.shopping_cart_outlined),
              ),
              if (cartCount > 0)
                Positioned(
                  right: 8,
                  top: 8,
                  child: Container(
                    padding:
                        const EdgeInsets.symmetric(horizontal: 6, vertical: 2),
                    decoration: BoxDecoration(
                      color: Colors.red,
                      borderRadius: BorderRadius.circular(10),
                    ),
                    child: Text(
                      '$cartCount',
                      style: const TextStyle(
                        color: Colors.white,
                        fontSize: 11,
                      ),
                    ),
                  ),
                ),
            ],
          ),
          IconButton(
            tooltip: 'Sign out',
            onPressed: () async {
              await AuthService.instance.signOut();
            },
            icon: const Icon(Icons.logout),
          ),
        ],
      ),
      body: Padding(
        padding: const EdgeInsets.all(12),
        child: LayoutBuilder(
          builder: (context, constraints) {
            final width = constraints.maxWidth;
            int count = 1;
            if (width > 1200) {
              count = 4;
            } else if (width > 900) {
              count = 3;
            } else if (width > 600) {
              count = 2;
            }

            return GridView.builder(
              itemCount: ProductRepository.products.length,
              gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
                crossAxisCount: count,
                crossAxisSpacing: 12,
                mainAxisSpacing: 12,
                childAspectRatio: 0.72,
              ),
              itemBuilder: (context, index) {
                final product = ProductRepository.products[index];
                return ProductCard(
                  product: product,
                  onView: () {
                    Navigator.of(context).push(
                      MaterialPageRoute(
                        builder: (_) => ProductDetailScreen(product: product),
                      ),
                    );
                  },
                  onAddToCart: () {
                    context.read<CartService>().addProduct(product);
                    ScaffoldMessenger.of(context).showSnackBar(
                      SnackBar(content: Text('${product.name} added to cart')),
                    );
                  },
                );
              },
            );
          },
        ),
      ),
    );
  }
}