access_policy-1.0.x-dev/modules/access_policy_ui/src/Form/AccessPolicyDeleteForm.php

<?php

namespace Drupal\access_policy_ui\Form;

use Drupal\Core\Entity\EntityConfirmFormBase;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Url;

/**
 * Builds the form to delete AccessPolicy entities.
 */
class AccessPolicyDeleteForm extends EntityConfirmFormBase {

  /**
   * Flag indicating whether this policy is being used.
   *
   * @var bool
   */
  protected $isUsed;

  /**
   * {@inheritdoc}
   */
  public function getQuestion() {
    return $this->t('Are you sure you want to delete @name?', ['@name' => $this->entity->label()]);
  }

  /**
   * {@inheritdoc}
   */
  public function getDescription() {
    if ($this->isUsed()) {
      return $this->t('The access policy @name is being used, and cannot be deleted.', ['@name' => $this->entity->label()]);
    }
    return parent::getDescription();
  }

  /**
   * {@inheritdoc}
   */
  public function getCancelUrl() {
    return new Url('entity.access_policy.collection');
  }

  /**
   * {@inheritdoc}
   */
  public function getConfirmText() {
    return $this->t('Delete');
  }

  /**
   * {@inheritdoc}
   */
  protected function actions(array $form, FormStateInterface $form_state) {
    $actions = parent::actions($form, $form_state);
    if ($this->isUsed()) {
      unset($actions['submit']);
    }

    return $actions;
  }

  /**
   * {@inheritdoc}
   */
  public function submitForm(array &$form, FormStateInterface $form_state) {
    $this->entity->delete();
    $this->messenger()->addMessage(
      $this->t('Deleted @label Access Policy.',
        [
          '@label' => $this->entity->label(),
        ]
      )
    );

    $form_state->setRedirectUrl($this->getCancelUrl());
  }

  /**
   * Determine whether this access policy is being used.
   *
   * @return bool
   *   TRUE if it's being used; FALSE otherwise.
   */
  private function isUsed() {
    if (!isset($this->isUsed)) {
      $this->isUsed = FALSE;
      $entity_type = $this->getEntity()->getTargetEntityTypeId();
      $query = $this->entityTypeManager->getStorage($entity_type)->getQuery();
      $query->accessCheck(FALSE);
      $query->condition('access_policy', $this->getEntity()->id());
      $query->count();
      $count = $query->execute();
      if ($count > 0) {
        $this->isUsed = TRUE;
      }
    }

    return $this->isUsed;
  }

}