Api/Netina.Repository/Handlers/Brands/GetBrandsQueryHandler.cs

using Netina.Domain.Entities.Brands;
using Netina.Domain.Entities.Products;

namespace Netina.Repository.Handlers.Brands;

public class GetBrandsQueryHandler(IRepositoryWrapper repositoryWrapper, IMediator mediator)
    : IRequestHandler<GetBrandsQuery, List<BrandSDto>>
{
    private readonly IMediator _mediator = mediator;

    public async Task<List<BrandSDto>> Handle(GetBrandsQuery request, CancellationToken cancellationToken)
    {
        IQueryable<Brand> baseBrands;
        List<BrandSDto> brands = new List<BrandSDto>();
        if (request.CategoryId != default)
        {
            //var products = await _mediator.Send(new GetProductsQuery(BrandIds: null,SpecialOffer: null, Page:0, SortBy: QuerySortBy.None,CategoryId: request.CategoryId, IsActive : null),
            //    cancellationToken);

            var cats = await mediator.Send(new GetProductCategoryChildrenQuery(request.CategoryId), cancellationToken);

            var brandGrouped = await repositoryWrapper.SetRepository<Product>()
                .TableNoTracking
                .Where(p => cats.Contains(p.CategoryId))
                .GroupBy(p=>p.BrandId)
                .ToListAsync(cancellationToken);

            foreach (var grouping in brandGrouped)
            {
                if (grouping.Key != default)
                {
                    var brand = await repositoryWrapper.SetRepository<Brand>()
                        .TableNoTracking
                        .Where(b => b.Id == grouping.Key)
                        .Select(BrandMapper.ProjectToSDto)
                        .FirstOrDefaultAsync(cancellationToken);
                    if(brand!=null)
                        brands.Add(brand);
                }
            }

            return brands;
        }

        if (request.BrandName != null)
        {
            baseBrands = repositoryWrapper.SetRepository<Brand>()
                .TableNoTracking
                .Where(b => b.PersianName.Trim().Contains(request.BrandName.Trim()))
                .OrderByDescending(b => b.CreatedAt);
        }
        else
        {

            baseBrands = repositoryWrapper.SetRepository<Brand>().TableNoTracking
                .OrderByDescending(b => b.CreatedAt);
        }

        if (request.Page != null)
        {
            brands = await baseBrands.Skip(request.Page.Value * 10).Take(10)
                .Select(BrandMapper.ProjectToSDto)
                .ToListAsync(cancellationToken);
        }
        else
        {

            brands = await baseBrands
                .Select(BrandMapper.ProjectToSDto)
                .ToListAsync(cancellationToken);
        }

        return brands;
    }
}