Working days calendar

[simpli]

Hi,

I want to implement a dojo calendar where upon a click a calendar covering a period would come up. I would like the user to then select the non working days on that calendar (presumably because its going to be shorter than to get him to choose the working days). I am planning to store those days he chooses as non working days in a database table called non working days with the date of the day. I plan to get the list of non working days and subtract it to the number of actual days in a month to get the number of working days in each month. I raked my brain to find another method but couldn't think of another one. Any one has something more efficient to propose?

 

Thanks,

JR