BBP_BuddyPress_Activity::get_activity_id( int $post_id )

	private static function get_activity_id( $post_id = 0 ) {

		// Try to get the activity ID of the post
		$activity_id = (int) get_post_meta( $post_id, '_bbp_activity_id', true );

		// Bail if no activity ID is in post meta
		if ( empty( $activity_id ) )
			return null;

		// Get the activity stream item, bail if it doesn't exist
		$existing = new BP_Activity_Activity( $activity_id );
		if ( empty( $existing->component ) ) {
			return null;
		}

		// Return the activity ID since we've verified the connection
		return $activity_id;
	}