class ContentEntityDeleteForm

class ContentEntityDeleteForm extends ContentEntityConfirmFormBase {
  use EntityDeleteFormTrait {
    getQuestion as traitGetQuestion;
    logDeletionMessage as traitLogDeletionMessage;
    getDeletionMessage as traitGetDeletionMessage;
    getCancelUrl as traitGetCancelUrl;
  }

  /**
   * {@inheritdoc}
   */
  public function buildForm(array $form, FormStateInterface $form_state) {
    $form = parent::buildForm($form, $form_state);

    /** @var \Drupal\Core\Entity\ContentEntityInterface $entity */
    $entity = $this
      ->getEntity();
    if ($entity
      ->isDefaultTranslation()) {
      if (count($entity
        ->getTranslationLanguages()) > 1) {
        $languages = [];
        foreach ($entity
          ->getTranslationLanguages() as $language) {
          $languages[] = $language
            ->getName();
        }
        $form['deleted_translations'] = [
          '#theme' => 'item_list',
          '#title' => $this
            ->t('The following @entity-type translations will be deleted:', [
            '@entity-type' => $entity
              ->getEntityType()
              ->getSingularLabel(),
          ]),
          '#items' => $languages,
        ];
        $form['actions']['submit']['#value'] = $this
          ->t('Delete all translations');
      }
    }
    else {
      $form['actions']['submit']['#value'] = $this
        ->t('Delete @language translation', [
        '@language' => $entity
          ->language()
          ->getName(),
      ]);
    }
    return $form;
  }

  /**
   * {@inheritdoc}
   */
  public function submitForm(array &$form, FormStateInterface $form_state) {

    /** @var \Drupal\Core\Entity\ContentEntityInterface $entity */
    $entity = $this
      ->getEntity();
    $message = $this
      ->getDeletionMessage();

    // Make sure that deleting a translation does not delete the whole entity.
    if (!$entity
      ->isDefaultTranslation()) {
      $untranslated_entity = $entity
        ->getUntranslated();
      $untranslated_entity
        ->removeTranslation($entity
        ->language()
        ->getId());
      $untranslated_entity
        ->save();
      $form_state
        ->setRedirectUrl($untranslated_entity
        ->toUrl('canonical'));
    }
    else {
      $entity
        ->delete();
      $form_state
        ->setRedirectUrl($this
        ->getRedirectUrl());
    }
    $this
      ->messenger()
      ->addStatus($message);
    $this
      ->logDeletionMessage();
  }

  /**
   * {@inheritdoc}
   */
  public function getCancelUrl() {

    /** @var \Drupal\Core\Entity\ContentEntityInterface $entity */
    $entity = $this
      ->getEntity();
    return $entity
      ->isDefaultTranslation() ? $this
      ->traitGetCancelUrl() : $entity
      ->toUrl('canonical');
  }

  /**
   * {@inheritdoc}
   */
  protected function getDeletionMessage() {

    /** @var \Drupal\Core\Entity\ContentEntityInterface $entity */
    $entity = $this
      ->getEntity();
    if (!$entity
      ->isDefaultTranslation()) {
      return $this
        ->t('The @entity-type %label @language translation has been deleted.', [
        '@entity-type' => $entity
          ->getEntityType()
          ->getSingularLabel(),
        '%label' => $entity
          ->label(),
        '@language' => $entity
          ->language()
          ->getName(),
      ]);
    }
    return $this
      ->traitGetDeletionMessage();
  }

  /**
   * {@inheritdoc}
   */
  protected function logDeletionMessage() {

    /** @var \Drupal\Core\Entity\ContentEntityInterface $entity */
    $entity = $this
      ->getEntity();
    if (!$entity
      ->isDefaultTranslation()) {
      $this
        ->logger($entity
        ->getEntityType()
        ->getProvider())
        ->notice('The @entity-type %label @language translation has been deleted.', [
        '@entity-type' => $entity
          ->getEntityType()
          ->getSingularLabel(),
        '%label' => $entity
          ->label(),
        '@language' => $entity
          ->language()
          ->getName(),
      ]);
    }
    else {
      $this
        ->traitLogDeletionMessage();
    }
  }

  /**
   * {@inheritdoc}
   */
  public function getQuestion() {

    /** @var \Drupal\Core\Entity\ContentEntityInterface $entity */
    $entity = $this
      ->getEntity();
    if (!$entity
      ->isDefaultTranslation()) {
      return $this
        ->t('Are you sure you want to delete the @language translation of the @entity-type %label?', [
        '@language' => $entity
          ->language()
          ->getName(),
        '@entity-type' => $this
          ->getEntity()
          ->getEntityType()
          ->getSingularLabel(),
        '%label' => $this
          ->getEntity()
          ->label(),
      ]);
    }
    return $this
      ->traitGetQuestion();
  }

}