DocumentOrganizer/Diligent.WebAPI.Business/Services/CategoryService.cs

using Diligent.WebAPI.Contracts.DTOs.Categories;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Diligent.WebAPI.Business.Services
{
    public class CategoryService : ICategoryService
    {
        private readonly DatabaseContext _context;
        private readonly IMapper _mapper;

        public CategoryService(DatabaseContext context, IMapper mapper)
        {
            _context = context;
            _mapper = mapper;
        }

        public async Task<List<CategoriesNamesResponse>> GetCategoriesNamesAsync() =>
            _mapper.Map<List<CategoriesNamesResponse>>(await _context.Categories.ToListAsync());

        public async Task<Category> GetCategoryEntityById(int id) =>
            await _context.Categories.Where(x => x.Id == id).FirstOrDefaultAsync();
    }
}