class EntityTestAccessControlHandler

class EntityTestAccessControlHandler extends EntityAccessControlHandler {
    
    /**
     * Allows to grant access to just the labels.
     *
     * @var bool
     */
    protected $viewLabelOperation = TRUE;
    
    /**
     * {@inheritdoc}
     */
    protected function checkAccess(EntityInterface $entity, $operation, AccountInterface $account) {
        
        /** @var \Drupal\entity_test\Entity\EntityTest $entity */
        // Always forbid access to entities with the label 'forbid_access', used for
        // \Drupal\system\Tests\Entity\EntityAccessControlHandlerTest::testDefaultEntityAccess().
        if ($entity->label() == 'forbid_access') {
            return AccessResult::forbidden();
        }
        if ($operation === 'view label' && $entity instanceof EntityTestLabel) {
            // Viewing the label of the 'entity_test_label' entity type is allowed.
            return AccessResult::allowed();
        }
        elseif (in_array($operation, [
            'view',
            'view label',
        ])) {
            if (!$entity->isDefaultTranslation()) {
                if ($entity instanceof EntityPublishedInterface && !$entity->isPublished()) {
                    return AccessResult::allowedIfHasPermission($account, 'view unpublished test entity translations');
                }
                else {
                    return AccessResult::allowedIfHasPermission($account, 'view test entity translations');
                }
            }
            if ($entity instanceof EntityPublishedInterface && !$entity->isPublished()) {
                return AccessResult::neutral('Unpublished entity');
            }
            return AccessResult::allowedIfHasPermission($account, 'view test entity');
        }
        elseif (in_array($operation, [
            'update',
            'delete',
        ])) {
            $access = AccessResult::allowedIfHasPermission($account, 'administer entity_test content');
            if (!$access->isAllowed() && $operation === 'update' && $account->hasPermission('edit own entity_test content')) {
                $access = $access->orIf(AccessResult::allowedIf($entity->getOwnerId() === $account->id()))
                    ->cachePerUser()
                    ->addCacheableDependency($entity);
            }
            return $access;
        }
        // Access to revisions is based on labels, so access can vary by individual
        // revisions, since the 'name' field can vary by revision.
        $labels = explode(',', $entity->label());
        $labels = array_map('trim', $labels);
        if (in_array($operation, [
            'view all revisions',
            'view revision',
        ], TRUE)) {
            return AccessResult::allowedIf(in_array($operation, $labels, TRUE));
        }
        elseif ($operation === 'revert') {
            return AccessResult::allowedIf(in_array('revert', $labels, TRUE));
        }
        elseif ($operation === 'delete revision') {
            return AccessResult::allowedIf(in_array('delete revision', $labels, TRUE));
        }
        // No opinion.
        return AccessResult::neutral();
    }
    
    /**
     * {@inheritdoc}
     */
    protected function checkCreateAccess(AccountInterface $account, array $context, $entity_bundle = NULL) {
        return AccessResult::allowedIfHasPermissions($account, [
            'administer entity_test content',
            'administer entity_test_with_bundle content',
            'create ' . $entity_bundle . ' entity_test_with_bundle entities',
        ], 'OR');
    }

}