public ActionResult SaveLecture(UserInformation user, LectureForEditing lecture)
        {
            if (user != null)
            {
                if (user.IsStudent)
                {
                    return View("Students limitations");
                }
                else
                {
                    try
                    {
                        if (!ModelState.IsValid) return View("EditLecture", lecture);
                        else
                        {
                            Lecture lect = new Lecture()
                            {
                                ID = lecture.ID,
                                Name = lecture.Name,
                                TopicId = lecture.TopicId,
                                OrderNumber = lecture.OrderNumber,
                                Homework = lecture.Homework,
                                LectureContent = lecture.LectureContent
                            };
                            _repository.SaveLecture(lect);

                            return RedirectToAction("EditTopic", "Topic", new { topicId = lecture.TopicId });
                        }
                    }
                    catch (Exception e)
                    {
                        return View("Error");
                    }

                }
            }
            else return View("UnauthorizedAccess");
        }