PIAPS_CW/DatabaseImplement/Implements/CartItemStorage.cs

using Contracts.BindingModels;
using Contracts.SearchModels;
using Contracts.StorageContracts;
using Contracts.ViewModels;
using DatabaseImplement.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace DatabaseImplement.Implements
{
    public class CartItemStorage : ICartItemStorage
    {
        public CartItemViewModel? Delete(CartItemBindingModel model)
        {
            using var context = new Database();
            var element = context.CartItems
            .FirstOrDefault(rec => rec.Id == model.Id);
            if (element != null)
            {
                context.CartItems.Remove(element);
                context.SaveChanges();
                return element.GetViewModel;
            }
            return null;
        }

        public CartItemViewModel? GetElement(CartItemSearchModel model)
        {
            if (!model.Id.HasValue)
            {
                return null;
            }
            using var context = new Database();
            return context.CartItems
            .FirstOrDefault(x => (model.Id.HasValue && x.Id == model.Id))?.GetViewModel;
        }

        public List<CartItemViewModel> GetFilteredList(CartItemSearchModel model)
        {
            if (model.UserId == Guid.Empty && string.IsNullOrEmpty(model.ProductName))
            {
                return new();
            }
            using var context = new Database();
            if (model.UserId != Guid.Empty)
            {
                return context.CartItems
                .Where(x => x.UserId == model.UserId)
                .ToList()
                .Select(x => x.GetViewModel)
                .ToList();
            }
            return context.CartItems
                .Where(x => x.ProductName.Contains(model.ProductName))
                .ToList()
                .Select(x => x.GetViewModel)
                .ToList();
        }

        public List<CartItemViewModel> GetFullList()
        {
            using var context = new Database();
            return context.CartItems
            .ToList()
            .Select(x => x.GetViewModel)
            .ToList();
        }

        public CartItemViewModel? Insert(CartItemBindingModel model)
        {
            using var context = new Database();
            var newItem = CartItem.Create(context, model);
            if (newItem == null)
            {
                return null;
            }

            context.CartItems.Add(newItem);
            context.SaveChanges();
            return newItem.GetViewModel;
        }

        public CartItemViewModel? Update(CartItemBindingModel model)
        {
            using var context = new Database();
            using var transaction = context.Database.BeginTransaction();
            try
            {
                var item = context.CartItems.FirstOrDefault(rec =>
                rec.Id == model.Id);

                if (item == null)
                {
                    return null;
                }
                item.Update(model);

                context.SaveChanges();
                transaction.Commit();
                return new();
            }
            catch
            {
                transaction.Rollback();
                throw;
            }
        }
    }
}