ANTOOZA-BACKEND/Application/Features/Admin/Store/Product/Get/Handler.cs

using Application.Abstractions.Data;
using Application.Abstractions.Messaging;
using Domain.Entities.Store.ValueObject;
using Microsoft.EntityFrameworkCore;
using SharedKernel.Results;

namespace Application.Features.Admin.Store.Product.Get;

public sealed class Handler(IAppDbContext db) : IQueryHandler<Query, Result<Response>>
{
    public async Task<Result<Response>> Handle(Query request, CancellationToken ct)
    {
        var product = await db.Product
            .AsNoTracking()
            .Include(c => c.Game)
            .Where(c => c.ID == request.ID)
            .Select(c => new Response(
                c.ID,
                c.GameID ?? 0,
                c.Game!.KorName,
                c.Name,
                c.Description,
                c.Thumbnail,
                c.Type,
                c.Price,
                c.DiscountType,
                c.DiscountValue,
                c.DiscountType == DiscountType.Percent
                    ? (c.Price - (c.Price * c.DiscountValue / 100) < 0 ? 0 : c.Price - (c.Price * c.DiscountValue / 100))
                    : c.DiscountType == DiscountType.Amount
                        ? (c.Price - c.DiscountValue < 0 ? 0 : c.Price - c.DiscountValue)
                        : c.Price,
                c.Stock,
                c.MinPurchase,
                c.MaxPurchase,
                c.IsActive,
                c.Order,
                c.SaleStartAt,
                c.SaleEndAt,
                c.CreatedAt,
                c.UpdatedAt,
                c.RequireDonationChannel
            ))
            .FirstOrDefaultAsync(ct);

        if (product is null)
        {
            return Result.Failure<Response>(Error.NotFound("Product.NotFound", "상품을 찾을 수 없습니다."));
        }

        return Result.Success(product);
    }
}