Auto Leave Salary payment in Payroll

Dear Guru,

I have one scenario given below:

I have Annual Leave Balance 45:

Emp apply Annual leave of from 1st May to 15th June Month.

So while processing Payroll for April Month: he will get the 45 days Salary extra in the month of April.

Now conditions is: The Payment of these 45 days on daily rate basis should come automatically in the payroll.... as Leave Salary Advance...

To  All Respectable GURU, please advice how can i do this....

Regards.

SHarma