Seting a promotion during Check out

There is already the ability when the user selects Product X to add automatically to the cart extra free products or other discounted products.

Is it possible with code modifications, instead of having the products added automatically to the cart to prompt the user with the discounted offers related to Products X and ask if he would like to add them to the cart or Continue checkout… ?

It would go like this:

Congratulations! your cart qualifies for the following special offers:

Product Y (-25%)

Product Z (-30%_