Send e-mail to partner role

Hello,

We want to send an order-confirmation-form to the customer. It should be send to the address of the partner role "ZM" if it exists. Otherwise it should be send to the partner role "AG". So we have two cases for sending an e-mail.

1. Partner role "AG" und "ZM" exists -> send E-Mail to "ZM"
2. Partner role "AG" exists -> send E-Mail to "AG"

What is the best way to enable this? Add condition records, implement an enhancement spot or another way?

Thanks, in advance.

Best regards,

Benjamin