public async Task <IActionResult> Index(string filterLastNameFragment, int?filterDocumentType, int?filterRowStatus, bool isRequestDataImmediately = false)
        {
            ViewBag.IsUserConsultant = User.IsInRole("Приёмная комиссия (консультанты)") ? true : false;

            ViewBag.filterLastNameFragment = filterLastNameFragment;
            ViewBag.filterDocumentType     = filterDocumentType;
            ViewBag.filterRowStatus        = filterRowStatus;

            ViewBag.UserDocumentTypes = _selectListRepository.GetSelectListAbiturientsUserDocumentTypes(filterDocumentType ?? 0);
            ViewBag.RowStatuses       = _selectListRepository.GetSelectListRowStatuses(filterRowStatus ?? 0);

            var userDocuments = _userDocumentRepository.GetUserDocuments()
                                .Where(ud => ud.AppUser.Abiturient != null /*&& ud.AppUser.Abiturient.AbiturientStatusId == (int) AbiturientStatusEnum.ConfirmedAbiturient*/);

            if (!isRequestDataImmediately)
            {
                return(View());
            }

            if (!string.IsNullOrWhiteSpace(filterLastNameFragment))
            {
                userDocuments = userDocuments.Where(ud => ud.AppUser.LastName.Contains(filterLastNameFragment));
            }
            if (filterDocumentType != null)
            {
                userDocuments = userDocuments.Where(ud => ud.FileDataTypeId == filterDocumentType);
            }
            if (filterRowStatus != null)
            {
                userDocuments = userDocuments.Where(ud => ud.RowStatusId == filterRowStatus);
            }

            return(View(await userDocuments.ToListAsync()));
        }