detection product in cart

[mike_gr]

Hi guys, i search on the forum but couldn't find a similar topic.

I need to give a free product to some customers (which i identify outside the shop) and they need to have a choice of 2 products of which they can only choose one (gift). Now i need to be able to detect when a product is in the cart or not (so they can't add both free products or quantities of more than one)

I am able to catch the product being added on cart.php using $idProduct from the add function, but i cant see if the product exists in the cart. How can you get cart.php to call the function which returns the cart contents? if i could do that a simple foreach would solve the problem for me

Does any of you guys know how to do it?

Thank you