class MediaAccessControlHandler

class MediaAccessControlHandler extends EntityAccessControlHandler implements EntityHandlerInterface {
    
    /**
     * The entity type manager.
     *
     * @var \Drupal\Core\Entity\EntityTypeManagerInterface
     */
    protected $entityTypeManager;
    
    /**
     * Constructs a MediaAccessControlHandler object.
     *
     * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
     *   The entity type definition.
     * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
     *   The entity type manager.
     */
    public function __construct(EntityTypeInterface $entity_type, EntityTypeManagerInterface $entity_type_manager) {
        parent::__construct($entity_type);
        $this->entityTypeManager = $entity_type_manager;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function createInstance(ContainerInterface $container, EntityTypeInterface $entity_type) {
        return new static($entity_type, $container->get('entity_type.manager'));
    }
    
    /**
     * {@inheritdoc}
     */
    protected function checkAccess(EntityInterface $entity, $operation, AccountInterface $account) {
        
        /** @var \Drupal\media\MediaInterface $entity */
        // Allow admin permission to override all operations.
        if ($account->hasPermission($this->entityType
            ->getAdminPermission())) {
            return AccessResult::allowed()->cachePerPermissions();
        }
        $type = $entity->bundle();
        $is_owner = $account->id() && $account->id() === $entity->getOwnerId();
        switch ($operation) {
            case 'view':
                if ($entity->isPublished()) {
                    $access_result = AccessResult::allowedIf($account->hasPermission('view media'))
                        ->cachePerPermissions()
                        ->addCacheableDependency($entity);
                    if (!$access_result->isAllowed()) {
                        $access_result->setReason("The 'view media' permission is required when the media item is published.");
                    }
                }
                elseif ($account->hasPermission('view own unpublished media')) {
                    $access_result = AccessResult::allowedIf($is_owner)->cachePerPermissions()
                        ->cachePerUser()
                        ->addCacheableDependency($entity);
                    if (!$access_result->isAllowed()) {
                        $access_result->setReason("The user must be the owner and the 'view own unpublished media' permission is required when the media item is unpublished.");
                    }
                }
                else {
                    $access_result = AccessResult::neutral()->cachePerPermissions()
                        ->addCacheableDependency($entity)
                        ->setReason("The user must be the owner and the 'view own unpublished media' permission is required when the media item is unpublished.");
                }
                return $access_result;
            case 'update':
                if ($account->hasPermission('edit any ' . $type . ' media')) {
                    return AccessResult::allowed()->cachePerPermissions();
                }
                if ($account->hasPermission('edit own ' . $type . ' media') && $is_owner) {
                    return AccessResult::allowed()->cachePerPermissions()
                        ->cachePerUser()
                        ->addCacheableDependency($entity);
                }
                // @todo Deprecate this permission in
                // https://www.drupal.org/project/drupal/issues/2925459.
                if ($account->hasPermission('update any media')) {
                    return AccessResult::allowed()->cachePerPermissions();
                }
                if ($account->hasPermission('update media') && $is_owner) {
                    return AccessResult::allowed()->cachePerPermissions()
                        ->cachePerUser()
                        ->addCacheableDependency($entity);
                }
                return AccessResult::neutral("The following permissions are required: 'update any media' OR 'update own media' OR '{$type}: edit any media' OR '{$type}: edit own media'.")->cachePerPermissions();
            case 'delete':
                if ($account->hasPermission('delete any ' . $type . ' media')) {
                    return AccessResult::allowed()->cachePerPermissions();
                }
                if ($account->hasPermission('delete own ' . $type . ' media') && $is_owner) {
                    return AccessResult::allowed()->cachePerPermissions()
                        ->cachePerUser()
                        ->addCacheableDependency($entity);
                }
                // @todo Deprecate this permission in
                // https://www.drupal.org/project/drupal/issues/2925459.
                if ($account->hasPermission('delete any media')) {
                    return AccessResult::allowed()->cachePerPermissions();
                }
                if ($account->hasPermission('delete media') && $is_owner) {
                    return AccessResult::allowed()->cachePerPermissions()
                        ->cachePerUser()
                        ->addCacheableDependency($entity);
                }
                return AccessResult::neutral("The following permissions are required: 'delete any media' OR 'delete own media' OR '{$type}: delete any media' OR '{$type}: delete own media'.")->cachePerPermissions();
            case 'view all revisions':
            case 'view revision':
                if ($account->hasPermission('view any ' . $type . ' media revisions') || $account->hasPermission("view all media revisions")) {
                    // Check the access to this revision and if the media passed in is not
                    // the default revision then access to that too.
                    $entity_access = $entity->access('view', $account, TRUE);
                    if (!$entity->isDefaultRevision()) {
                        $media_storage = $this->entityTypeManager
                            ->getStorage($entity->getEntityTypeId());
                        $entity_access->andIf($this->access($media_storage->load($entity->id()), 'view', $account, TRUE));
                    }
                    return AccessResult::allowed()->cachePerPermissions()
                        ->andIf($entity_access);
                }
                return AccessResult::neutral()->cachePerPermissions();
            case 'revert':
                return AccessResult::allowedIfHasPermission($account, 'revert any ' . $type . ' media revisions')->cachePerPermissions()
                    ->addCacheableDependency($entity);
            case 'delete revision':
                return AccessResult::allowedIfHasPermission($account, 'delete any ' . $type . ' media revisions')->cachePerPermissions()
                    ->addCacheableDependency($entity);
            default:
                return AccessResult::neutral()->cachePerPermissions();
        }
    }
    
    /**
     * {@inheritdoc}
     */
    protected function checkCreateAccess(AccountInterface $account, array $context, $entity_bundle = NULL) {
        $permissions = [
            'administer media',
            'create media',
            'create ' . $entity_bundle . ' media',
        ];
        return AccessResult::allowedIfHasPermissions($account, $permissions, 'OR');
    }

}