ComputerHardwareStore_YouAreProgrammer/ComputerHardwareStore/ComputerHardwareStoreDatabaseImplement/Implements/PurchaseStorage.cs

using ComputerHardwareStoreContracts.BindingModels;
using ComputerHardwareStoreContracts.SearchModels;
using ComputerHardwareStoreContracts.StorageContracts;
using ComputerHardwareStoreContracts.ViewModels;
using ComputerHardwareStoreDatabaseImplement.Models;
using Microsoft.EntityFrameworkCore;

namespace ComputerHardwareStoreDatabaseImplement.Implements
{
    public class PurchaseStorage : IPurchaseStorage
    {
        public List<PurchaseViewModel> GetFullList()
        {
            using var context = new ComputerHardwareStoreDBContext();
            return context.Purchases
                .Include(p => p.Builds)
                .ThenInclude(p => p.Build)
                .Include(p => p.Products)
                .ThenInclude(p => p.Product)
                .Select(p => p.GetViewModel)
                .ToList();
        }
        
        public List<PurchaseViewModel> GetFilteredList(PurchaseSearchModel model)
        {
            using var context = new ComputerHardwareStoreDBContext();
            return context.Purchases
                .Include(p => p.Builds)
                .ThenInclude(p => p.Build)
                .Include(p => p.Products)
                .ThenInclude(p => p.Product)
                .Where(p =>
                (model.Id.HasValue && p.Id == model.Id) ||
                ((model.DateFrom.HasValue && model.DateTo.HasValue) &&
                ((model.DateFrom <= p.DateCreate && p.DateCreate <= model.DateTo) ||
                (p.DateImplement.HasValue && p.DateCreate < model.DateFrom && model.DateFrom < p.DateImplement)))
                )
                .Select(p => p.GetViewModel)
                .ToList();
        }

        public PurchaseViewModel? GetElement(PurchaseSearchModel model)
        {
            if (!model.Id.HasValue)
            {
                return null;
            }
            using var context = new ComputerHardwareStoreDBContext();
            return context.Purchases
                .Include(p => p.Builds)
                .ThenInclude(p => p.Build)
                .Include(p => p.Products)
                .ThenInclude(p => p.Product)
                .FirstOrDefault(p => p.Id == model.Id)?
                .GetViewModel;
        }

        public PurchaseViewModel? Insert(PurchaseBindingModel model)
        {
            using var context = new ComputerHardwareStoreDBContext();
            var newPurchase = Purchase.Create(context, model);
            if (newPurchase == null)
            {
                return null;
            }
            context.Purchases.Add(newPurchase);
            context.SaveChanges();
            return newPurchase.GetViewModel;
        }

        public PurchaseViewModel? Update(PurchaseBindingModel model)
        {
            using var context = new ComputerHardwareStoreDBContext();
            using var transaction = context.Database.BeginTransaction();
            try
            {
                var purchase = context.Purchases
                    .Include(p => p.Builds)
                    .ThenInclude(p => p.Build)
                    .Include(p => p.Products)
                    .ThenInclude(p => p.Product)
                    .FirstOrDefault(p => p.Id == model.Id);
                if (purchase == null)
                {
                    return null;
                }
                purchase.Update(model);
                context.SaveChanges();
                transaction.Commit();
                return purchase.GetViewModel;
            }
            catch
            {
                transaction.Rollback();
                throw;
            }
        }

        public PurchaseViewModel? Delete(PurchaseBindingModel model)
        {
            using var context = new ComputerHardwareStoreDBContext();
            var element = context.Purchases
                .Include(p => p.Builds)
                .ThenInclude(p => p.Build)
                .Include(p => p.Products)
                .ThenInclude(p => p.Product)
                .FirstOrDefault(o => o.Id == model.Id);
            if (element != null)
            {
                context.Purchases.Remove(element);
                context.SaveChanges();
                return element.GetViewModel;
            }
            return null;
        }
    }
}