private void ReturnToMainMenu_Click(object sender, RoutedEventArgs e)
        {
            StudentMenuWindow studentMenu = new StudentMenuWindow(_userId);

            studentMenu.Show();
            Close();
        }
        private void Save_Click(object sender, RoutedEventArgs e)
        {
            UserController.SetFirstName(_userId, Name.Text);
            UserController.SetSurname(_userId, Surname.Text);
            UserController.SetPassword(_userId, Password.Text);

            StudentMenuWindow studentMenu = new StudentMenuWindow(_userId);

            studentMenu.Show();
            Close();
        }
        private async void ButtonLogin_ClickAsync(object sender, RoutedEventArgs e)
        {
            bool   result   = int.TryParse(TextBoxUsername.Text, out int username);
            string password = TextBoxPassword.Password;

            bool works = await UserController.CredentialsMatchAsync(Convert.ToInt32(username), password);

            if (!works || !result)
            {
                return;
            }

            User user = UserController.GetUser(username);

            switch (user.Type)
            {
            case "Student":
            {
                StudentMenuWindow studentMenu = new StudentMenuWindow(user.User_ID);
                studentMenu.Show();
                Close();
                break;
            }

            case "Lecture":
            {
                LectureMenuWindow lectureMenu = new LectureMenuWindow(user.User_ID);
                lectureMenu.Show();
                Close();
                break;
            }

            default:
            {
                break;
            }
            }
        }