Implemented shopping carts functionality elements

LiteCharms.Features/ShoppingCarts/Queries/Handlers/GetShoppingCartItemsQueryHandler.cs

@@ -0,0 +1,30 @@
+using LiteCharms.Extensions;
+using LiteCharms.Infrastructure.Database;
+using LiteCharms.Models;
+
+namespace LiteCharms.Features.ShoppingCarts.Queries.Handlers;
+
+public class GetShoppingCartItemsQueryHandler(IDbContextFactory<LeadGeneratorDbContext> contextFactory) : IRequestHandler<GetShoppingCartItemsQuery, Result<ShoppingCartItem[]>>
+{
+    public async ValueTask<Result<ShoppingCartItem[]>> Handle(GetShoppingCartItemsQuery request, CancellationToken cancellationToken)
+    {
+		try
+		{
+            using var context = await contextFactory.CreateDbContextAsync(cancellationToken);
+
+            if (!await context.ShoppingCarts.AnyAsync(i => i.Id == request.ShoppingCartId, cancellationToken))
+                return Result.Fail($"Shopping cart could not be found with id {request.ShoppingCartId}");
+
+            var items = await context.ShoppingCartItems.AsNoTracking()
+                .Where(i => i.ShoppingCartId == request.ShoppingCartId).ToArrayAsync(cancellationToken);
+
+            return items?.Length > 0
+                ? Result.Ok(items.Select(i => i.ToModel()).ToArray())
+                : Result.Fail<ShoppingCartItem[]>($"Failed to retrieve shopping cart items with id {request.ShoppingCartId}");
+        }
+		catch (Exception ex)
+		{
+            return Result.Fail<ShoppingCartItem[]>(new Error(ex.Message).CausedBy(ex));
+        }
+    }
+}