public async Task <ActionResult> Book(int roomId, DateTime fromDate, DateTime toDate)
        {
            var daysCount   = toDate - fromDate;
            var reservation = new Reservation
            {
                StartDate = fromDate,
                EndDate   = toDate,
                UserId    = User.Identity.GetUserId(),
                DayCount  = daysCount.Days,
                RoomId    = roomId
            };
            var result = await reservationRepository.Book(reservation);

            if (result == null)
            {
                return(Content("Something went wrong: the room is not available at this date"));
            }
            return(Content("Reservation is Successfull"));
        }