// src/Webshop.Application/Services/Public/Interfaces/IDiscountService.cs
using System;
using System.Collections.Generic;
using System.Threading.Tasks;
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<DiscountCalculationResult> CalculateDiscountAsync(List<OrderItem> orderItems, string? couponCode);
    }
}