hook for wp affiliate with marketpress

<?php

function custom_mp_cart_payment( $content, $type ){

    if ($type == 'confirmation'){
        $content .= 'Your code here.';
        $sale_amt = "199"; //TODO - The commission is calculated based on this amount
$unique_transaction_id = "Txn-ID"; //TODO - The unique transaction ID for reference
$email = "Buyer-email-goes-here"; //TODO - Customer email for record
$referrer = $_COOKIE['ap_id'];//Cookie value is read from the customer's browser
do_action('wp_affiliate_process_cart_commission', array("referrer" => $referrer, "sale_amt" =>$sale_amt, "txn_id"=>$unique_transaction_id, "buyer_email"=>$email));
    }

return $content;
}
add_filter('_mp_cart_payment', 'custom_mp_cart_payment', 10, 2 );

?>