I have a javascript code that looks up the discount assigned to the account. And this amount will be subtracted from the amount in the price of each opportunity product. I would like to execute this code when a product is added to the opportunity and as soon as the total amount of the opportunity changes, the operations have already been done. Is there a method to do it? I've tried adding the event when the opportunity's "detailed amount" field changes, but it runs and doesn't reflect the change.