public function copyShadowProperties(AbstractMappingEvent $event)
    {
        $document = $event->getDocument();

        if (!$this->supports($document)) {
            return;
        }

        if (!$event->getDocument()->isShadowLocaleEnabled()) {
            $this->copyToShadows($event->getDocument(), $event->getNode());
        } else {
            $this->copyFromShadow($event->getDocument(), $event->getNode());
        }
    }