Add-to-Cart Video barrier

For Virtuemart 2.0 we need a special product detail template on product pages of one certain manufacturer. Whenever a customer clicks on the Add-to-cart button, there must appear a popup window with the explanation video of the manufacturer. Without having seen this video, it not allowed to put the article into the shopping cart. Here is an example page of how it must look like when it is finished: [login to view URL] Popup should be a modal window. Please note: This confirmation is only necessary for certain products. Of course there are other products where the add-to-cart happens just to be normal. We need from you all modified files. PLEASE NOTE: This is NOT about doing a complete template for us. It is ONLY adjusting some PHP-files for the Add-to-Cart function. PLEASE NOTE: We will certainly NOT consider any bid higher than 100 EUR/130 USD.