public IActionResult GetTimeSlots()
        {
            var result = _timeSlotService.GetTimeSlots();

            if (result == null || result.Count == 0)
            {
                return(NoContent());
            }
            return(Ok(result));
        }
        public async Task <IEnumerable <TimeSlotBm> > AddTimeSlotsAsync(DateTime start, DateTime end, int duration, int queueId)
        {
            var correctTimeFormat = start.Ticks < end.Ticks && duration > 0;

            Guard.Argument(() => correctTimeFormat).True();

            var timeSlots = _timeSlotService.GetTimeSlots(start, end, duration, queueId);

            await _storage.TimeSlots.CreateAsync(timeSlots);

            await _storage.SaveAsync();

            return(_mapper.Map <IEnumerable <TimeSlotBm> >(timeSlots));
        }