public ViewResult Checkout(Cart cart, ShippingDetails shippingDetails)
        {
            
            if (cart.Lines.Count() == 0)
            {
                ModelState.AddModelError("", "Sorry, your cart is empty");
            }
            if (ModelState.IsValid)
            {
                //orderProcessor.ProcessOrder(cart, shippingDetails);
                cart.Clear();
                return View("Completed");

            }
            else
            {
                return View(shippingDetails);
            }
        }