discounts überarbeitet

Webshop.Application/Services/Public/Interfaces/IDiscountService.cs

@@ -6,8 +6,24 @@ using Webshop.Domain.Entities;
 
 namespace Webshop.Application.Services.Public.Interfaces
 {
+    /// <summary>
+    /// Stellt das Ergebnis der Rabattberechnung dar.
+    /// </summary>
+    public class DiscountCalculationResult
+    {
+        /// <summary>
+        /// Der gesamte berechnete Rabattbetrag.
+        /// </summary>
+        public decimal TotalDiscountAmount { get; set; } = 0;
+
+        /// <summary>
+        /// Die IDs der Rabatte, die erfolgreich angewendet wurden.
+        /// </summary>
+        public List<Guid> AppliedDiscountIds { get; set; } = new List<Guid>();
+    }
+
     public interface IDiscountService
     {
-        Task<decimal> CalculateDiscountAsync(List<OrderItem> orderItems, string? couponCode);
+        Task<DiscountCalculationResult> CalculateDiscountAsync(List<OrderItem> orderItems, string? couponCode);
     }
 }