public async Task <ActionResult> SignupForShiftDay(ShiftDaySignupInput input) { var shiftDay = await _shiftsService.GetShiftDayByIdAsync(input.ShiftDayId); if (shiftDay == null) { return(NotFound()); } if (shiftDay.Shift != null && shiftDay.Shift.DepartmentId != DepartmentId) { return(Unauthorized()); } var signup = await _shiftsService.SignupForShiftDayAsync(shiftDay.ShiftId, shiftDay.Day, input.GroupId, UserId); return(CreatedAtAction(nameof(SignupForShiftDay), new { id = signup.ShiftSignupId }, signup)); }