I need to extend Magento 2.1 to allow products to be added to cart by the square foot (flooring). However the products are sold by the carton. Therefore I need an extension that will allow the visitor to provide square footage, while the site converts up to the next full carton. Of course, each product that is sold this way would have a SFperCarton attribute set to a numeric value greater than zero.
I have a lot of experience as a software developer, however I have almost no experience with PHP. I am looking for community's opinion on the relative difficulty for creating this extension for Magento 2.1.
Also, are there any good resources that anyone knows of to get me started? Any help would be greatly appreciated.