Action button to recalculate commissions in Affiliate store

Commissions that we have to pay to our affiliate stores (batch production) customers are based on the total quantity sold so the actual calculation can only be done after the close date.

So after the close date, I would like to go to the products page and update the commissions for each product based on qty. Then initiate an action button that will recalculate the commission for that period (store start date - store close date)

Also, it would be nice if we can then print a report of the commission breakdown in the following format

Commission for XXX store from store_start_date to store_close_date

Item - Qty sold - Comm(ea) - Total Commission