public IActionResult AddReservation(UploadableReservation reservation)
        {
            if (ModelState.IsValid)
            {
                Boolean isReservationAdded = Schedule.AddReservation(reservation);

                if (isReservationAdded)
                {
                    return(RedirectToAction("Index", "Rooms", new { area = "" }));
                }
            }

            ViewBag.Week               = reservation.Week;
            ViewBag.Day                = reservation.Day;
            ViewBag.Year               = reservation.Year;
            ViewBag.RoomName           = reservation.Classroom;
            ViewBag.StartLessonHour    = reservation.StartHour;
            ViewBag.IsReservationAdded = false;
            return(View(reservation));
        }