Custom cart rules

[yahoo42]

Hi,

 

I'm new to Prestashop development and I can't figure out how to achieve my goal.

 

I have some products that are packed with another kind of product. For example, I would like to be able to sell a camera packed with a memory card. When the user add a camera to the cart, he can choose between compatible cards and the chosen card should appear in the cart as free.

 

I have an idea about how to make the first part (i.e: detecting when a product is added to the cart and presenting the list of compatible cards to the user) but I can't figure out how to make the card free. I see this just like a custom cart rule where I can programmatically update the price of a product depending on other products presents in the cart, but I don't know if it's possible.

 

Thank you in advance.