class NodeRevisionDeleteForm

class NodeRevisionDeleteForm extends ConfirmFormBase {
    
    /**
     * The node revision.
     *
     * @var \Drupal\node\NodeInterface
     */
    protected $revision;
    
    /**
     * The node storage.
     *
     * @var \Drupal\Core\Entity\EntityStorageInterface
     */
    protected $nodeStorage;
    
    /**
     * The node type storage.
     *
     * @var \Drupal\Core\Entity\EntityStorageInterface
     */
    protected $nodeTypeStorage;
    
    /**
     * The database connection.
     *
     * @var \Drupal\Core\Database\Connection
     */
    protected $connection;
    
    /**
     * The date formatter service.
     *
     * @var \Drupal\Core\Datetime\DateFormatterInterface
     */
    protected $dateFormatter;
    
    /**
     * Constructs a new NodeRevisionDeleteForm.
     *
     * @param \Drupal\Core\Entity\EntityStorageInterface $node_storage
     *   The node storage.
     * @param \Drupal\Core\Entity\EntityStorageInterface $node_type_storage
     *   The node type storage.
     * @param \Drupal\Core\Database\Connection $connection
     *   The database connection.
     * @param \Drupal\Core\Datetime\DateFormatterInterface $date_formatter
     *   The date formatter service.
     */
    public function __construct(EntityStorageInterface $node_storage, EntityStorageInterface $node_type_storage, Connection $connection, DateFormatterInterface $date_formatter) {
        $this->nodeStorage = $node_storage;
        $this->nodeTypeStorage = $node_type_storage;
        $this->connection = $connection;
        $this->dateFormatter = $date_formatter;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container) {
        $entity_type_manager = $container->get('entity_type.manager');
        return new static($entity_type_manager->getStorage('node'), $entity_type_manager->getStorage('node_type'), $container->get('database'), $container->get('date.formatter'));
    }
    
    /**
     * {@inheritdoc}
     */
    public function getFormId() {
        return 'node_revision_delete_confirm';
    }
    
    /**
     * {@inheritdoc}
     */
    public function getQuestion() {
        return $this->t('Are you sure you want to delete the revision from %revision-date?', [
            '%revision-date' => $this->dateFormatter
                ->format($this->revision
                ->getRevisionCreationTime()),
        ]);
    }
    
    /**
     * {@inheritdoc}
     */
    public function getCancelUrl() {
        return new Url('entity.node.version_history', [
            'node' => $this->revision
                ->id(),
        ]);
    }
    
    /**
     * {@inheritdoc}
     */
    public function getConfirmText() {
        return $this->t('Delete');
    }
    
    /**
     * {@inheritdoc}
     */
    public function buildForm(array $form, FormStateInterface $form_state, NodeInterface $node_revision = NULL) {
        $this->revision = $node_revision;
        $form = parent::buildForm($form, $form_state);
        return $form;
    }
    
    /**
     * {@inheritdoc}
     */
    public function submitForm(array &$form, FormStateInterface $form_state) {
        $this->nodeStorage
            ->deleteRevision($this->revision
            ->getRevisionId());
        $this->logger('content')
            ->notice('@type: deleted %title revision %revision.', [
            '@type' => $this->revision
                ->bundle(),
            '%title' => $this->revision
                ->label(),
            '%revision' => $this->revision
                ->getRevisionId(),
        ]);
        $node_type = $this->nodeTypeStorage
            ->load($this->revision
            ->bundle())
            ->label();
        $this->messenger()
            ->addStatus($this->t('Revision from %revision-date of @type %title has been deleted.', [
            '%revision-date' => $this->dateFormatter
                ->format($this->revision
                ->getRevisionCreationTime()),
            '@type' => $node_type,
            '%title' => $this->revision
                ->label(),
        ]));
        $form_state->setRedirect('entity.node.canonical', [
            'node' => $this->revision
                ->id(),
        ]);
        if ($this->connection
            ->query('SELECT COUNT(DISTINCT [vid]) FROM {node_field_revision} WHERE [nid] = :nid', [
            ':nid' => $this->revision
                ->id(),
        ])
            ->fetchField() > 1) {
            $form_state->setRedirect('entity.node.version_history', [
                'node' => $this->revision
                    ->id(),
            ]);
        }
    }

}