Refactor CartService to use async methods for cart operations and integrate gRPC for backend synchronization

src/FrontOffice.Main/ConfigureServices.cs

@@ -10,6 +10,7 @@ using FrontOffice.BFF.Transaction.Protobuf.Protos.Transaction;
 using FrontOffice.BFF.User.Protobuf.Protos.User;
 using FrontOffice.BFF.UserAddress.Protobuf.Protos.UserAddress;
 using FrontOffice.BFF.UserOrder.Protobuf.Protos.UserOrder;
+using FrontOffice.BFF.ShopingCart.Protobuf.Protos.ShopingCart;
 using FrontOffice.Main.Utilities;
 
 namespace Microsoft.Extensions.DependencyInjection;
@@ -78,6 +79,7 @@ public static class ConfigureServices
         // Products gRPC
         services.AddScoped(CreateAuthenticatedClient<FrontOffice.BFF.Products.Protobuf.Protos.Products.ProductsContract.ProductsContractClient>);
         services.AddScoped(CreateAuthenticatedClient<TransactionContract.TransactionContractClient>);
+        services.AddScoped(CreateAuthenticatedClient<ShopingCartContract.ShopingCartContractClient>);
 
         return services;
     }

src/FrontOffice.Main/FrontOffice.Main.csproj

@@ -15,6 +15,7 @@
     <PackageReference Include="Foursat.FrontOffice.BFF.UserAddress.Protobuf" Version="0.0.114" />
     <PackageReference Include="Foursat.FrontOffice.BFF.UserOrder.Protobuf" Version="0.0.112" />
     <PackageReference Include="FrontOffice.BFF.Products.Protobuf" Version="0.0.11" />
+    <PackageReference Include="FrontOffice.BFF.ShopingCart.Protobuf" Version="0.0.12" />
     <PackageReference Include="MudBlazor" Version="8.14.0" />
     <PackageReference Include="Blazored.LocalStorage" Version="4.5.0" />
     <PackageReference Include="Mapster" Version="7.4.0" />

src/FrontOffice.Main/Pages/Store/Cart.razor.cs

@@ -14,14 +14,14 @@ public partial class Cart : ComponentBase, IDisposable
         CartService.OnChange += StateHasChanged;
     }
 
-    private void ChangeQty(long productId, int value)
+    private async Task ChangeQty(long productId, int value)
     {
-        CartService.UpdateQuantity(productId, value);
+        await CartService.UpdateQuantity(productId, value);
     }
 
-    private void Remove(long productId)
+    private async Task Remove(long productId)
     {
-        CartService.Remove(productId);
+        await CartService.Remove(productId);
     }
 
     private void ProceedCheckout()

src/FrontOffice.Main/Pages/Store/CheckoutSummary.razor.cs

@@ -72,7 +72,7 @@ public partial class CheckoutSummary : ComponentBase
         };
 
         var id = await OrderService.CreateOrderAsync(order);
-        Cart.Clear();
+        await Cart.Clear();
         Snackbar.Add("سفارش با موفقیت ثبت شد.", Severity.Success);
         Navigation.NavigateTo($"{RouteConstants.Store.OrderDetail}{id}");
     }

src/FrontOffice.Main/Pages/Store/ProductDetail.razor.cs

@@ -21,10 +21,10 @@ public partial class ProductDetail : ComponentBase
         _loading = false;
     }
 
-    private void AddToCart()
+    private async Task AddToCart()
     {
         if (_product is null) return;
-        Cart.Add(_product, _qty);
+        await Cart.Add(_product, _qty);
     }
 
     private static string FormatPrice(long price) => string.Format("{0:N0} تومان", price);

src/FrontOffice.Main/Pages/Store/Products.razor.cs

@@ -31,9 +31,9 @@ public partial class Products : ComponentBase, IDisposable
         await Load();
     }
 
-    private void AddToCart(Product p)
+    private async Task AddToCart(Product p)
     {
-        Cart.Add(p, 1);
+        await Cart.Add(p, 1);
     }
 
     private static string FormatPrice(long price) => string.Format("{0:N0} تومان", price);

src/FrontOffice.Main/Utilities/CartService.cs

@@ -1,3 +1,6 @@
+using FrontOffice.BFF.ShopingCart.Protobuf.Protos.ShopingCart;
+using Google.Protobuf.WellKnownTypes;
+
 namespace FrontOffice.Main.Utilities;
 
 public record CartItem(long ProductId, string Title, string ImageUrl, long UnitPrice, int Quantity)
@@ -7,14 +10,21 @@ public record CartItem(long ProductId, string Title, string ImageUrl, long UnitP
 
 public class CartService
 {
+    private readonly ShopingCartContract.ShopingCartContractClient _client;
     private readonly List<CartItem> _items = new();
     public event Action? OnChange;
 
+    public CartService(ShopingCartContract.ShopingCartContractClient client)
+    {
+        _client = client;
+        _ = LoadFromServerAsync();
+    }
+
     public IReadOnlyList<CartItem> Items => _items.AsReadOnly();
     public long Total => _items.Sum(i => i.LineTotal);
     public int Count => _items.Sum(i => i.Quantity);
 
-    public void Add(Product product, int quantity = 1)
+    public async Task Add(Product product, int quantity = 1)
     {
         if (quantity <= 0) return;
         var existing = _items.FirstOrDefault(i => i.ProductId == product.Id);
@@ -28,9 +38,22 @@ public class CartService
             _items[idx] = existing with { Quantity = existing.Quantity + quantity };
         }
         Notify();
+
+        try
+        {
+            await _client.AddNewUserCartAsync(new AddNewUserCartRequest
+            {
+                ProductId = product.Id,
+                Count = quantity
+            });
+        }
+        catch
+        {
+            // Best-effort sync with backend; keep local state on failure
+        }
     }
 
-    public void UpdateQuantity(long productId, int quantity)
+    public async Task UpdateQuantity(long productId, int quantity)
     {
         var existing = _items.FirstOrDefault(i => i.ProductId == productId);
         if (existing is null) return;
@@ -42,20 +65,87 @@ public class CartService
         var idx = _items.IndexOf(existing);
         _items[idx] = existing with { Quantity = quantity };
         Notify();
+
+        try
+        {
+            await _client.UpdateUserCartAsync(new UpdateUserCartRequest
+            {
+                UserCartId = productId,
+                Count = quantity
+            });
+        }
+        catch
+        {
+            // Best-effort sync with backend; keep local state on failure
+        }
     }
 
-    public void Remove(long productId)
+    public async Task Remove(long productId)
     {
         _items.RemoveAll(i => i.ProductId == productId);
         Notify();
+
+        try
+        {
+            // Interpret Count=0 as remove from cart
+            await _client.UpdateUserCartAsync(new UpdateUserCartRequest
+            {
+                UserCartId = productId,
+                Count = 0
+            });
+        }
+        catch
+        {
+            // Best-effort sync with backend; keep local state on failure
+        }
     }
 
-    public void Clear()
+    public async Task Clear()
     {
+        var productIds = _items.Select(i => i.ProductId).ToList();
         _items.Clear();
         Notify();
+
+        try
+        {
+            foreach (var id in productIds)
+            {
+                await _client.UpdateUserCartAsync(new UpdateUserCartRequest
+                {
+                    UserCartId = id,
+                    Count = 0
+                });
+            }
+        }
+        catch
+        {
+            // Best-effort sync with backend; keep local state on failure
+        }
     }
 
     private void Notify() => OnChange?.Invoke();
-}
 
+    private async Task LoadFromServerAsync()
+    {
+        try
+        {
+            var response = await _client.GetAllUserCartAsync(new Empty());
+            _items.Clear();
+            foreach (var m in response.Models)
+            {
+                var item = new CartItem(
+                    ProductId: m.Id,
+                    Title: m.Title ?? string.Empty,
+                    ImageUrl: string.IsNullOrWhiteSpace(m.ImagePath) ? string.Empty : UrlUtility.DownloadUrl + m.ImagePath,
+                    UnitPrice: m.Price,
+                    Quantity: m.SaleCount > 0 ? m.SaleCount : 1);
+                _items.Add(item);
+            }
+            Notify();
+        }
+        catch
+        {
+            // If backend is unreachable or user is unauthenticated, fall back to local-only cart.
+        }
+    }
+}