Write some Software

Hi there, I am looking to create a shopify if/else statement to allow overselling on different variants within a product which updates through AJAX to refresh the statement as a new variant is selected. - I want to be able to display a message if the product is less than 0 QTY to say available to order but with a lead time - When a product has a QTY of equal to or more than 0, then a message displays saying that the product is ready to ship. -This needs to update with each variant. Currently it works but only for the first variant, it doesn't update the message depending on variant. I need the statement to refresh like the price does through AJAX. -The message also needs to update with the QTY selected. Eg if there is 1 in stock it and the customer selects a QTY of 2 , the message with display 'Your order is partly ready to ship!".