Attach & email PDF files to customers who make/purchase event bookings

If it is possible could you please create the functionality for PDF files to be sent in the automated email responses when customers make a booking for an online event. The online event I am hosting requires additional information to be sent to the customer in the form of PDF files and although the product in shopify has these PDF files attached to them, they are not being forward to the customer in the usual way that a digital file attachment would when purchasing a digital product.