FullCalendar - random busy block and detecting click on busy block

Question

I am working with fullcalendar here and have some problems with the appearance of it.

I want to have a working time, for example from 8:00 am to 5:00 pm and I know how to manage to gray out slots in non-working time with the businessHours option:

businessHours: {
  dow: [1,2,3,4,5],
  start: '08:00',
  end: '17:00'
}

But let's say, for example, I want to show only events and not all the working time, so at the beginning businessHours is set as:

businessHours: {
  dow: [1,2,3,4,5],
  start: '00:00',
  end: '00:00'
}

Now, when some things here are selected, besides events that are already on the calendar I am showing the full working time for the day.

But here's my problem:

I have some resources unavailable, let's say, from 8:30 to 9:00 and from 13:45 to 14:00, and from 15:00 to 16:00.

1) Is there a way to make those blocks unavailable for making events, so when click on the block is registered, a message pops up: "This slot (or something) is unavailable.

2) Is there a way to register click on non-working hours and slots (blocks), all of them, inside the calendar (from 8:30 to 9:00 and from 13:45 to 14:00, and from 15:00 to 16:00) and outside of it - from 00:00 to 8:00 and from 17:00 to 00:00?