public ActionResult Create(Appointment appointment)
 {
     if (_repo.isAppointmentAvailable(appointment))
     {
         if (_custRepo.ThisCustomerExists(appointment.CustomerId))
         {
             if (_servRepo.ThisProviderExists(appointment.ProviderId))
             {
                 _repo.Add(appointment);
                 return(RedirectToAction(nameof(Index)));
             }
             else
             {
                 ModelState.AddModelError("",
                                          "There is no Service ProProviderIdvider that exists with the selected ID..." +
                                          "I'm begging you, think very carefully and give this just one more shot, Big Guy");
                 return(View());
             }
         }
         else
         {
             ModelState.AddModelError("CustomerId",
                                      "There is no customer that exists with that ID... Please try.. maybe... one more time?");
             return(View());
         }
     }
     else
     {
         ModelState.AddModelError("AppTime",
                                  "The selected Service Provider is not available for an appointment at this time. Please try again.");
         return(View());
     }
 }