Drupal Commerce: Form (add to Cart) ID from Node ID?

I’m working on a website made with Drupal 7 and the Commerce Module, with a “Products” page containing a view of all the products and for each one a “Buy Now” button (which is a form). Now, I want that button to also be inside each products’ page, that is within the template for the Product content type.

I have been able to create a node for single products (see code below), but I want to modify the general template and not to create a different template for each product.

# node--181.tpl.php  <form class="commerce-add-to-cart commerce-cart-add-to-cart-form-24" autocomplete="off" action="/en/products" method="post" id="commerce-cart-add-to-cart-form-24" accept-charset="UTF-8"> <div><input type="hidden" name="product_id" value="24"> <input type="hidden" name="form_id" value="commerce_cart_add_to_cart_form_24"> <input name='form_token' type='hidden' value='<?php print drupal_get_token('commerce_cart_add_to_cart_form_24'); ?>'> <div id="edit-line-item-fields--9" class="form-wrapper"></div><input type="hidden" name="quantity" value="1"> <input type="submit" id="edit-submit--9" name="op" value="Add to cart" class="form-submit"> </div> </form> 

So, my question boils down to: that “24” is the ID of the form associated with a specific product (node ID 181), but how can I use a generic form, so that such a value will be generated for the correct product?