public ActionResult UpdateCars(CarViewModel data)
        {
            try
            {
                if (Session["userId"] == null)
                {
                    return(RedirectToAction("Login", "Account"));
                }
                manager = new StorageManager(UnitOfWork);
                // for updating the record
                if (new Guid(data.Id) != Guid.Empty)
                {
                    Car objectCars = new Car()
                    {
                        Id     = new Guid(data.Id),
                        Brand  = data.Brand,
                        Model  = data.Model,
                        Year   = data.Year,
                        Price  = data.Price,
                        New    = data.New,
                        UserId = Convert.ToString(Session["userId"])
                    };
                    manager.AddCar(objectCars);
                }
                else
                {
                    // for saving the record
                    Car objectCars = new Car()
                    {
                        Id     = Guid.NewGuid(),
                        Brand  = data.Brand,
                        Model  = data.Model,
                        Year   = data.Year,
                        Price  = data.Price,
                        New    = data.New,
                        UserId = Convert.ToString(Session["userId"])
                    };
                    manager.AddCar(objectCars);
                }
            }
            catch (Exception ex)
            {
                // handling the error
                logger.Error(ex.ToString());
            }

            return(RedirectToAction("Index"));
        }