bbp_update_topic_last_active_id( int $topic_id, int $active_id )

function bbp_update_topic_last_active_id( $topic_id = 0, $active_id = 0 ) {

	// If it's a reply, then get the parent (topic id)
	if ( bbp_is_reply( $topic_id ) ) {
		$topic_id = bbp_get_reply_topic_id( $topic_id );
	} else {
		$topic_id = bbp_get_topic_id( $topic_id );
	}

	if ( empty( $active_id ) ) {
		$active_id = bbp_get_public_child_last_id( $topic_id, bbp_get_reply_post_type() );
	}

	// Adjust last_id's based on last_reply post_type
	if ( empty( $active_id ) || !bbp_is_reply( $active_id ) ) {
		$active_id = $topic_id;
	}

	// Update only if published
	if ( bbp_get_public_status_id() === get_post_status( $active_id ) ) {
		update_post_meta( $topic_id, '_bbp_last_active_id', (int) $active_id );
	}

	return apply_filters( 'bbp_update_topic_last_active_id', (int) $active_id, $topic_id );
}