public async Task <object> SetState(AttendanceInputModel attendanceInputModel, int stateId)
        {
            var model = await _context.Attendance.FindAsync(attendanceInputModel.AttendanceId);

            model.StateId = stateId;
            _context.Entry(model).State = EntityState.Modified;

            try
            {
                await _context.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!AttendanceModelExists(model.AttendanceId))
                {
                    return("not found");
                }
                else
                {
                    throw;
                }
            }

            return("no content");
        }
        public async Task <IActionResult> PutAttendanceModel(AttendanceInputModel attendanceInputModel, int stateId)
        {
            var result = await _attendanceRepository.SetState(attendanceInputModel, stateId);

            if (result.Equals("no content"))
            {
                return(NoContent());
            }
            else if (result.Equals("not found"))
            {
                return(NotFound());
            }
            else
            {
                return(BadRequest());
            }
        }
        public async Task <object> Add(AttendanceInputModel attendanceInputModel)
        {
            int stateId = (await _stateRepository.GetDefaultState()).StateId;
            var model   = new AttendanceModel
            {
                LabId     = attendanceInputModel.LabId,
                StudentId = attendanceInputModel.StudentId,
                StateId   = stateId
            };

            _context.Attendance.Add(model);
            try
            {
                await _context.SaveChangesAsync();
            }
            catch (Exception)
            {
                return("bad request");
            }
            return(model);
        }
        public async Task <ActionResult <AttendanceModel> > PostAttendanceModel(int labId)
        {
            var labModel = await _labRepository.GetById(labId);

            if (labModel == null)
            {
                return(BadRequest());
            }
            var groupModel = await _groupRepository.GetById(labModel.GroupId);

            if (groupModel == null)
            {
                return(BadRequest());
            }

            object result;

            if (groupModel.Students == null)
            {
                return(BadRequest());
            }
            foreach (var studentModel in groupModel.Students)
            {
                var model = new AttendanceInputModel
                {
                    AttendanceId = 0,
                    LabId        = labId,
                    StudentId    = studentModel.StudentId
                };
                result = await _attendanceRepository.Add(model);

                if (result.Equals("bad request"))
                {
                    return(BadRequest());
                }
            }

            return(NoContent());
        }