paypal - zoho invoice integration

paypal - zoho invoice integration

I'd like to know if it is possible to integrate paypal and zoho invoice in this way:

1. the customer buys something on my website and click on paypal button;
2. the customer pays using paypal;
3. paypal communicate with zoho invoice that automatically create an invoice and send it to the customer

I've searched and didn't find a solution, the only one I can imagine now is to use paypal IPN and interface it with zoho invoice APIs, but i'd like to find that there is a simpler and out of the box solution :-)