Pre-sale PRO: gift money to spend in the store

Hi there

I need to create a rule like this:
The person adds 100 items from a specific category and gets up to 50$ to spend in the entire store (not discounted from this 100 items, but only from additional purchases).
Basically 50$ discount from the cart, but the 100 items total unaffected by this

Will this plugin be able to help me?

Thanks in advance!