Magento - set discount on a product before the cart

Question

i'm new on magento and i'm working on a module that permt a user to choose and to have the gfit with the product that he purchase. my question is, how can i set a discount on specific product in the checkout ? i've used : i make the modification in the observer on the event

checkout_cart_add_product_complete

.

$_cart_products = Mage::getModel("checkout/cart") -> getItems();

//foreache...
//if ...

$_cart_product->setDiscountAmount($realPrice-$giftPrice);
$_cart_product->setBaseDiscountAmount($realPrice-$giftPrice);
$_cart_product->save();

But it dosen't work thank you for your help :)

Answer 1

you don't need to code for doing this,just go to admin and you will see promotion tab,just select this, from here you can define promotion rules for products