class LocalTaskAccessControlHandler

class LocalTaskAccessControlHandler extends EntityAccessControlHandler {

  /**
   * {@inheritdoc}
   */
  protected function checkAccess(EntityInterface $entity, $operation, AccountInterface $account) {
    if ($operation == 'delete') {
      return AccessResult::forbidden();
    }
    if ($account
      ->hasPermission('administer tmgmt') || $account
      ->hasPermission('administer translation tasks')) {

      // Administrators can do everything.
      return AccessResult::allowed()
        ->cachePerPermissions();
    }
    switch ($operation) {
      case 'view':
      case 'update':
        return AccessResult::allowedIfHasPermission($account, 'provide translation services');

        // Custom operations.

      // Custom operations.
      case 'unassign':
        return AccessResult::allowedIf($entity->tuid->target_id == $account
          ->id() && $account
          ->hasPermission('provide translation services'));
    }
    return AccessResult::neutral();
  }

  /**
   * {@inheritdoc}
   */
  protected function checkFieldAccess($operation, FieldDefinitionInterface $field_definition, AccountInterface $account, FieldItemListInterface $items = NULL) {
    if ($operation == 'edit') {
      return AccessResult::allowedIfHasPermissions($account, [
        'administer tmgmt',
        'administer translation tasks',
      ]);
    }
    return parent::checkFieldAccess($operation, $field_definition, $account, $items);
  }

  /**
   * {@inheritdoc}
   */
  protected function checkCreateAccess(AccountInterface $account, array $context, $entity_bundle = NULL) {
    return AccessResult::allowedIfHasPermission($account, 'administer translation tasks')
      ->orIf(AccessResult::allowedIfHasPermission($account, 'administer tmgmt'));
  }

}