Capture Credit Card (Authorize.net) in Opencart When Order is Marked as Shipped

Currently with opencart when using [login to view URL] as the payment module you can either Authorize the Credit Card or you can Capture the Credit Card. We are currently authorizing the credit card when the customer purchases a product off our Opencart website. We would like it to Automatically Capture the Credit Card when we mark the order as Shipped. Currently Opencart does not support this and we have to manually capture the credit card for each order. We have also integrated with Paypal - therefore no errors should occur when we mark Paypal orders as Shipped. This project is URGENT and bidder must be able to start work right away.