Online payment option in email even if none selected

Online payment option in email even if none selected

For invoices that we email to customers.  The email template includes the line 
" View your invoice then make an easy  online payment ."

If an online payment option is not selected for the invoice when we create it, the email still includes this link even though we are not allowing them to pay online.

Removing the text from the invoice template is not an option because we include online payment for SOME invoices.

Basically, the online payment link in the email should be conditional.... if there is an online payment option selected for the invoice, include the link.  If no online payment option selected, do not include the link.

Thanks!