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<?php

namespace AppBundle\Form\EventListener;

use AppBundle\Entity\Listing;
use AppBundle\Entity\Property;
use AppBundle\Entity\Reservation;
use Doctrine\ORM\EntityManagerInterface;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\Form\FormEvent;
use Symfony\Component\Form\FormEvents;
use Symfony\Component\Form\FormInterface;

/**
 * Class AddReservationListingsSubscriber
 * @package AppBundle\Form\EventListener
 */
class AddReservationListingsSubscriber implements EventSubscriberInterface
{
    private $em;

    /**
     * AddReservationListingsSubscriber constructor.
     * @param EntityManagerInterface $em
     */
    public function __construct(EntityManagerInterface $em)
    {
        $this->em = $em;
    }

    /**
     * Returns an array of event names this subscriber wants to listen to.
     *
     * @return array The event names to listen to
     */
    public static function getSubscribedEvents()
    {
        return [
            FormEvents::PRE_SET_DATA => 'onPreSetData',
            FormEvents::PRE_SUBMIT   => 'onPreSubmit',
        ];
    }

    /**
     * @param FormEvent $event
     */
    public function onPreSubmit(FormEvent $event)
    {
        $form = $event->getForm();
        $data = $event->getData();

        if (! isset($data['property']))  return;

        $property = $this->em->getRepository(Property::class)->findOneById($data['property']);
        $this->addListingsElement($form, $property);
    }


    /**
     * @param FormEvent $event
     */
    public function onPreSetData(FormEvent $event)
    {
        /** @var Reservation $reservation */
        $reservation = $event->getData();
        $form = $event->getForm();

        if (null == $reservation) return;

        $property = $reservation->getProperty();
        $this->addListingsElement($form, $property);
    }

    /**
     * @param FormInterface $form
     * @param Property $property
     */
    protected function addListingsElement(FormInterface $form, Property $property = null)
    {
        $form
            ->add('property', 'entity', [
                    'class'     => 'AppBundle:Property',
                    'data'      => $property,
                    'property'  => 'descriptiveName',
                    'mapped'      => false,
                    'empty_value' => '-- Choose --',
                    'attr' => ['class' => 'app-dynamic-property'],
                ]
            );

        $listings = $property ? $property->getListings()->toArray() : [];

        $form->add('listing', 'entity', array(
            'class'         => Listing::class,
            'property'    => 'descriptiveName',
//            'empty_value'   => '-- Select a property --',
            'choices'       => $listings,
            'attr' => [ 'startRow' => true, 'groupClass' => 'col-xs-6 col-tight', 'class' => 'app-dynamic-listing']
        ));
    }
}