public IHttpResponse Create()
        {
            var orders = Db.Orders.Where(o => o.Status == Status.Active).ToList();

            orders.ForEach(o => o.Status = Status.Completed);

            var receipt = new Receipt
            {
                Cashier  = Db.Users.Single(c => c.Username.Equals(User.Username)),
                IssuedOn = DateTime.UtcNow
            };

            Db.Orders.UpdateRange(orders);
            Db.SaveChanges();

            Db.Receipts.Add(receipt);
            Db.SaveChanges();

            var receiptOrder = new ReceiptOrder
            {
                Orders  = orders,
                Receipt = receipt
            };

            Db.ReceiptOrders.Add(receiptOrder);
            Db.SaveChanges();

            var userReceipt = new UserReceipt
            {
                Receipt = receipt,
                Cashier = receipt.Cashier
            };

            Db.UserReceipts.Add(userReceipt);
            Db.SaveChanges();

            var orderViewModels = receiptOrder.Orders
                                  .Select(o => new OrderViewModel
            {
                Id       = o.Id,
                Product  = o.Product.Name,
                Quantity = o.Quantity,
                Price    = o.Product.Price
            })
                                  .ToList();

            var receiptViewModel = new ReceiptDetailsViewModel
            {
                Id       = receipt.Id,
                Orders   = orderViewModels,
                IssuedOn = receipt.IssuedOn.ToString("dd/MM/yyyy"),
                Cashier  = receipt.Cashier.Username
            };

            var total = orderViewModels.Sum(ovm => ovm.Quantity * ovm.Price);

            receiptViewModel.Total = total;

            return(View("/receipts/details", receiptViewModel));
        }
        public UserReceipt CreateUserReceipt(Receipt receipt)
        {
            var userReceipt = new UserReceipt
            {
                Receipt = receipt,
                Cashier = receipt.Cashier
            };

            context.UserReceipts.Add(userReceipt);
            context.SaveChanges();



            return(userReceipt);
        }