update cart

lib/features/cart/data/datasources/cart_local_datasource.dart

@@ -0,0 +1,179 @@
+/// Local Data Source: Cart Storage
+///
+/// Handles local storage of cart items using Hive for offline access.
+/// Supports offline-first functionality and cart persistence.
+library;
+
+import 'package:hive_ce/hive.dart';
+
+import 'package:worker/core/constants/storage_constants.dart';
+import 'package:worker/core/database/hive_service.dart';
+import 'package:worker/core/errors/exceptions.dart';
+import 'package:worker/features/cart/data/models/cart_item_model.dart';
+
+/// Cart Local Data Source Interface
+abstract class CartLocalDataSource {
+  /// Save cart items to local storage
+  ///
+  /// [items] - List of cart items to save
+  Future<void> saveCartItems(List<CartItemModel> items);
+
+  /// Get cart items from local storage
+  ///
+  /// Returns list of cart items
+  Future<List<CartItemModel>> getCartItems();
+
+  /// Add item to local cart
+  ///
+  /// [item] - Cart item to add
+  Future<void> addCartItem(CartItemModel item);
+
+  /// Update item in local cart
+  ///
+  /// [item] - Cart item to update
+  Future<void> updateCartItem(CartItemModel item);
+
+  /// Remove items from local cart
+  ///
+  /// [itemIds] - Product IDs to remove
+  Future<void> removeCartItems(List<String> itemIds);
+
+  /// Clear all items from local cart
+  Future<void> clearCart();
+
+  /// Get cart item count
+  ///
+  /// Returns total number of items
+  Future<int> getCartItemCount();
+
+  /// Get cart total
+  ///
+  /// Returns total amount
+  Future<double> getCartTotal();
+}
+
+/// Cart Local Data Source Implementation
+class CartLocalDataSourceImpl implements CartLocalDataSource {
+  CartLocalDataSourceImpl(this._hiveService);
+
+  final HiveService _hiveService;
+
+  /// Get cart box as Box<dynamic> (following best practices)
+  Box<dynamic> get _cartBox => _hiveService.getBox<dynamic>(HiveBoxNames.cartBox);
+
+  @override
+  Future<void> saveCartItems(List<CartItemModel> items) async {
+    try {
+      // Clear existing items
+      await _cartBox.clear();
+
+      // Save new items with productId as key
+      for (final item in items) {
+        await _cartBox.put(item.productId, item);
+      }
+    } catch (e) {
+      throw StorageException('Failed to save cart items: $e');
+    }
+  }
+
+  @override
+  Future<List<CartItemModel>> getCartItems() async {
+    try {
+      // Get all cart items from box using .whereType() for type safety
+      final items = _cartBox.values
+          .whereType<CartItemModel>()
+          .toList();
+
+      return items;
+    } catch (e) {
+      throw StorageException('Failed to get cart items: $e');
+    }
+  }
+
+  @override
+  Future<void> addCartItem(CartItemModel item) async {
+    try {
+      // Check if item already exists
+      final existingItem = _cartBox.get(item.productId);
+
+      if (existingItem != null && existingItem is CartItemModel) {
+        // Update quantity if item exists
+        final updatedItem = existingItem.copyWith(
+          quantity: existingItem.quantity + item.quantity,
+          subtotal: (existingItem.quantity + item.quantity) * existingItem.unitPrice,
+        );
+        await _cartBox.put(item.productId, updatedItem);
+      } else {
+        // Add new item
+        await _cartBox.put(item.productId, item);
+      }
+    } catch (e) {
+      throw StorageException('Failed to add cart item: $e');
+    }
+  }
+
+  @override
+  Future<void> updateCartItem(CartItemModel item) async {
+    try {
+      // Update or add item
+      await _cartBox.put(item.productId, item);
+    } catch (e) {
+      throw StorageException('Failed to update cart item: $e');
+    }
+  }
+
+  @override
+  Future<void> removeCartItems(List<String> itemIds) async {
+    try {
+      // Remove items by productId keys
+      for (final itemId in itemIds) {
+        await _cartBox.delete(itemId);
+      }
+    } catch (e) {
+      throw StorageException('Failed to remove cart items: $e');
+    }
+  }
+
+  @override
+  Future<void> clearCart() async {
+    try {
+      await _cartBox.clear();
+    } catch (e) {
+      throw StorageException('Failed to clear cart: $e');
+    }
+  }
+
+  @override
+  Future<int> getCartItemCount() async {
+    try {
+      final items = await getCartItems();
+
+      // Sum up all quantities
+      final totalQuantity = items.fold<double>(
+        0.0,
+        (sum, item) => sum + item.quantity,
+      );
+
+      return totalQuantity.toInt();
+    } catch (e) {
+      throw StorageException('Failed to get cart item count: $e');
+    }
+  }
+
+  @override
+  Future<double> getCartTotal() async {
+    try {
+      final items = await getCartItems();
+
+      // Sum up all subtotals
+      final total = items.fold<double>(
+        0.0,
+        (sum, item) => sum + item.subtotal,
+      );
+
+      return total;
+    } catch (e) {
+      throw StorageException('Failed to get cart total: $e');
+    }
+  }
+}