OSCOMMERCE - PRODUCT_INFO PAGE ENHANCED

THE JOB TO BE DONE for this OSCOMMERCE STORE: - Create a new product attribute for the product_info page giving the ability to the customer to personalize the size of its printed document. - So, for that, we need an input field for the width, an input field for the length and a readonly input field for the result in square meters. - The result in square meters must be multiplied by a price (already set in the database). - The "result input field" and the new price generated must be updated in the page, without reloading the page. - This new attribute must work with the other ones - The new price must be written/added in the shopping cart, email, invoice etc... when we checkout.