DateTime DataZPickera = new DateTime();
            DateTime DatePermissionFrom = DateTime.ParseExact(candidate.PermissionDateFrom, "yyyy-MM-dd",System.Globalization.CultureInfo.InvariantCulture);
            DateTime DatePermissionTo = DateTime.ParseExact(candidate.PermissionDateTo, "yyyy-MM-dd", System.Globalization.CultureInfo.InvariantCulture);
            int Offset = candidate.PermissionFromOffset;

            if (DataZPickera >= DatePermissionFrom)
            {
                candidate.TravelData_IntendedDateOfArrivalInPoland = DataZPickera.AddDays(Offset).ToString("yyyy-MM-dd");
            }
            else if (DatePermissionFrom > DataZPickera.AddDays(Offset))
            {
                candidate.TravelData_IntendedDateOfArrivalInPoland = DatePermissionFrom.ToString("yyyy-MM-dd");
            }
            else
            {
                candidate.TravelData_IntendedDateOfArrivalInPoland = DataZPickera.AddDays(Offset).ToString("yyyy-MM-dd");
            }