public IActionResult AddPayment(int id, decimal amount)
        {
            var db = new BlessDiamondRepository(_connectionString);

            db.AddPayment(id, amount);
            return(Json(DateTime.Now));
        }
        public IActionResult AddSale(Product product, Buyer buyer, History history)
        {
            var db = new BlessDiamondRepository(_connectionString);

            db.AddSale(product, buyer, history);

            return(Redirect("/home/ViewAllSales"));
        }
        public IActionResult ViewSale(int id)
        {
            var db = new BlessDiamondRepository(_connectionString);

            return(View(db.GetSale(id)));
        }
        public IActionResult ViewAllSales()
        {
            var db = new BlessDiamondRepository(_connectionString);

            return(View(db.GetAllSales()));
        }