Wired up CartDrawel and ProductView to cart service and local storage

MidrandBookshop/Components/Pages/ProductView.razor.cs

@@ -3,6 +3,7 @@ using LiteCharms.Features.MidrandBooks.Authors;
 using LiteCharms.Features.MidrandBooks.Authors.Models;
 using LiteCharms.Features.MidrandBooks.Products;
 using LiteCharms.Features.MidrandBooks.Products.Models;
+using Microsoft.AspNetCore.Cors.Infrastructure;
 using MidrandBookshop.Services.ShoppingCart;
 
 namespace MidrandBookshop.Components.Pages;
@@ -13,8 +14,10 @@ public partial class ProductView : ComponentBase
 
     [Inject] private ProductService ProductService { get; set; } = default!;
     [Inject] private AuthorService AuthorService { get; set; } = default!;
-    [Inject] private CartService CartService { get; set; } = default!;
     [Inject] private NavigationManager Navigation { get; set; } = default!;
+    [Inject] private CartService CartService { get; set; } = default!;
+
+    protected Services.ShoppingCart.Models.Cart ShoppingCart => CartService?.ShoppingCart!;
 
     protected bool IsLoading { get; private set; } = true;
     protected Product? CurrentProduct { get; private set; }
@@ -29,6 +32,9 @@ public partial class ProductView : ComponentBase
 
     protected Author? CurrentAuthor { get; private set; }
 
+    private static Func<Services.ShoppingCart.Models.Cart, long, int> getCartItemQuantity = (shoppingCart, productPriceId) => 
+        shoppingCart.Items.FirstOrDefault(p => p.Price!.Id == productPriceId)?.Quantity ?? 1;
+
     protected override async Task OnParametersSetAsync()
     {
         try
@@ -85,20 +91,26 @@ public partial class ProductView : ComponentBase
         }
     }
 
-    protected void IncreaseQty()
+    protected async void IncreaseQty()
     {
-        Quantity++;
-
         if (CurrentPrice is not null)
-            CartService.UpdateQuantity(CurrentPrice!.Id, Quantity);
-    }
-    protected void DecreaseQty() 
-    {
-        if (Quantity > 1)
         {
-            Quantity--;
+            CartService.UpdateQuantity(CurrentPrice!.Id, 1);
+                        
+            Quantity = getCartItemQuantity(ShoppingCart, CurrentPrice.Id);
 
-            CartService.UpdateQuantity(CurrentPrice!.Id, Quantity);
+            await CartService.SaveCartToStorageAsync();
+        }
+    }
+    protected async void DecreaseQty() 
+    {
+        if (Quantity >= 1)
+        {
+            CartService.UpdateQuantity(CurrentPrice!.Id, -1);
+
+            Quantity = getCartItemQuantity(ShoppingCart, CurrentPrice.Id);
+
+            await CartService.SaveCartToStorageAsync();
         }
     }
 
@@ -108,8 +120,20 @@ public partial class ProductView : ComponentBase
 
         if (CurrentPrice is not null)
         {
-            CartService.AddItem(CurrentPrice);
-            Quantity++;
+            if(ShoppingCart.Items.Any(p => p.Price!.Id == CurrentPrice.Id))
+            {
+                CartService.UpdateQuantity(CurrentPrice.Id, 1);
+
+                await CartService.SaveCartToStorageAsync();
+
+                return;
+            }
+
+            CartService.AddItem(CurrentPrice, CurrentProduct, CurrentAuthor!);
+
+            Quantity = getCartItemQuantity(ShoppingCart, CurrentPrice.Id);
+
+            await CartService.SaveCartToStorageAsync();
         }
     }