Calculating duration between two date/time fields, excluding weekend/holiday/overnight hours

[Bharat Kavade]

We have two date/time fields which are filled in our workflow step. We want to calculate the duration between these two date/time fields using script in calculated number field.

However, the catch is that the duration should exclude the weekends, holidays and 9 PM to 9 AM everyday.

Can anyone suggest a script I can add to the calculated number field for duration?