public function send(\Swift_Mime_SimpleMessage $message, &$failedRecipients = null): int
    {
        self::$deliveredMessages[] = $message;

        $this->systemLogger->log('Sent email to ' . $this->buildStringFromEmailAndNameArray($message->getTo()), LOG_DEBUG, [
            'message' => $message->toString()
        ]);

        return count((array)$message->getTo()) + count((array)$message->getCc()) + count((array)$message->getBcc());
    }