public async Task <IActionResult> Buy(long id)
        {
            decimal price = await _auctionService.Buy(Convert.ToInt64(HttpContext.Session.GetString("userId")), id);

            TempData["Message"] = MessageHelper.YourBidOffer + String.Format("{0:0.00}", price);
            return(RedirectToAction("Detail", new { id = id }));
        }
        public async Task <IActionResult> Buy(Buy buy)
        {
            decimal price = await _auctionService.Buy(buy.UserId, buy.ProductId);

            return(Ok(new { message = StringHelper.PurchaseRequestAccepted + price }));
        }