SUBD/ForumDatabaseImplement/Implements/CategoryStorage.cs

using ForumContracts.BindingModels;
using ForumContracts.SearchModels;
using ForumContracts.StorageContracts;
using ForumContracts.ViewModels;
using ForumDatabaseImplement.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ForumDatabaseImplement.Implements
{
    public class CategoryStorage : ICategoryStorage
    {
        public CategoryViewModel? Delete(CategoryBindingModel model)
        {
            using var context = new ForumDataBase();

            var res = context.Categories
                .FirstOrDefault(x => x.Id == model.Id);

            if (res != null)
            {
                context.Categories.Remove(res);
                context.SaveChanges();
            }

            return res?.GetViewModel;
        }

        public CategoryViewModel? GetElement(CategorySearchModel model)
        {
            using var context = new ForumDataBase();

            if (model.Id.HasValue)
                return context.Categories
                    .FirstOrDefault(x => x.Id == model.Id)
                    ?.GetViewModel;

            return null;
        }

        public List<CategoryViewModel> GetFilteredList(CategorySearchModel model)
        {
            if (model == null)
            {
                return new();
            }

            if (model.Id.HasValue)
            {
                var res = GetElement(model);

                return res != null ? new() { res } : new();
            }

            if (model.Name != null)
            {
                using var context = new ForumDataBase();

                return context.Categories
                    .Where(x => x.Name.Equals(model.Name))
                    .Select(x => x.GetViewModel)
                    .ToList();
            }

            return new();
        }

        public List<CategoryViewModel> GetFullList()
        {
            using var context = new ForumDataBase();

            return context.Categories
                .Select(x => x.GetViewModel)
                .ToList();
        }

        public CategoryViewModel? Insert(CategoryBindingModel model)
        {
            using var context = new ForumDataBase();

            var res = Category.Create(model);

            if (res != null)
            {
                context.Categories.Add(res);
                context.SaveChanges();
            }

            return res?.GetViewModel;
        }

        public CategoryViewModel? Update(CategoryBindingModel model)
        {
            using var context = new ForumDataBase();

            var res = context.Categories
                .FirstOrDefault(x => x.Id == model.Id);

            if (res != null)
            {
                res.Update(model);
                context.SaveChanges();
            }

            return res?.GetViewModel;
        }
    }
}