public ActionResult SaveApiUser(ApiUserViewModel viewModel)
        {
            var response = _adminMediator.SaveApiUser(viewModel);

            ModelState.Clear();

            SetUserMessage(response.Message);

            switch (response.Code)
            {
            case AdminMediatorCodes.SaveApiUser.FailedValidation:
                response.ValidationResult.AddToModelState(ModelState, "SearchViewModel");
                return(View("ApiUser", response.ViewModel));

            case AdminMediatorCodes.SaveApiUser.Error:
                return(RedirectToRoute(ManagementRouteNames.AdminViewApiUser, new { viewModel.ExternalSystemId }));

            case AdminMediatorCodes.SaveApiUser.Ok:
                return(RedirectToRoute(ManagementRouteNames.AdminViewApiUser, new { viewModel.ExternalSystemId }));

            default:
                throw new InvalidMediatorCodeException(response.Code);
            }
        }