class File

class File extends ContentEntityBase implements FileInterface {
    use EntityChangedTrait;
    use EntityOwnerTrait;
    
    /**
     * {@inheritdoc}
     */
    public function getFilename() {
        return $this->get('filename')->value;
    }
    
    /**
     * {@inheritdoc}
     */
    public function setFilename($filename) {
        $this->get('filename')->value = $filename;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getFileUri() {
        return $this->get('uri')->value;
    }
    
    /**
     * {@inheritdoc}
     */
    public function setFileUri($uri) {
        $this->get('uri')->value = $uri;
    }
    
    /**
     * {@inheritdoc}
     */
    public function createFileUrl($relative = TRUE) {
        
        /** @var \Drupal\Core\File\FileUrlGeneratorInterface $file_url_generator */
        $file_url_generator = \Drupal::service('file_url_generator');
        return $relative ? $file_url_generator->generateString($this->getFileUri()) : $file_url_generator->generateAbsoluteString($this->getFileUri());
    }
    
    /**
     * {@inheritdoc}
     */
    public function getMimeType() {
        return $this->get('filemime')->value;
    }
    
    /**
     * {@inheritdoc}
     */
    public function setMimeType($mime) {
        $this->get('filemime')->value = $mime;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getSize() {
        $filesize = $this->get('filesize')->value;
        return isset($filesize) ? (int) $filesize : NULL;
    }
    
    /**
     * {@inheritdoc}
     */
    public function setSize($size) {
        $this->get('filesize')->value = $size;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getCreatedTime() {
        $created = $this->get('created')->value;
        return isset($created) ? (int) $created : NULL;
    }
    
    /**
     * {@inheritdoc}
     */
    public function isPermanent() {
        return $this->get('status')->value == static::STATUS_PERMANENT;
    }
    
    /**
     * {@inheritdoc}
     */
    public function isTemporary() {
        return $this->get('status')->value == 0;
    }
    
    /**
     * {@inheritdoc}
     */
    public function setPermanent() {
        $this->get('status')->value = static::STATUS_PERMANENT;
    }
    
    /**
     * {@inheritdoc}
     */
    public function setTemporary() {
        $this->get('status')->value = 0;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function preCreate(EntityStorageInterface $storage, array &$values) {
        // Automatically detect filename if not set.
        if (!isset($values['filename']) && isset($values['uri'])) {
            $values['filename'] = \Drupal::service('file_system')->basename($values['uri']);
        }
        // Automatically detect filemime if not set.
        if (!isset($values['filemime']) && isset($values['uri'])) {
            $values['filemime'] = \Drupal::service('file.mime_type.guesser')->guessMimeType($values['uri']);
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function preSave(EntityStorageInterface $storage) {
        parent::preSave($storage);
        // The file itself might not exist or be available right now.
        $uri = $this->getFileUri();
        $size = @filesize($uri);
        // Set size unless there was an error.
        if ($size !== FALSE) {
            $this->setSize($size);
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public static function preDelete(EntityStorageInterface $storage, array $entities) {
        parent::preDelete($storage, $entities);
        foreach ($entities as $entity) {
            // Delete all remaining references to this file.
            $file_usage = \Drupal::service('file.usage')->listUsage($entity);
            if (!empty($file_usage)) {
                foreach ($file_usage as $module => $usage) {
                    \Drupal::service('file.usage')->delete($entity, $module);
                }
            }
            // Delete the actual file. Failures due to invalid files and files that
            // were already deleted are logged to watchdog but ignored, the
            // corresponding file entity will be deleted.
            try {
                \Drupal::service('file_system')->delete($entity->getFileUri());
            } catch (FileException $e) {
                // Ignore and continue.
            }
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
        
        /** @var \Drupal\Core\Field\BaseFieldDefinition[] $fields */
        $fields = parent::baseFieldDefinitions($entity_type);
        $fields += static::ownerBaseFieldDefinitions($entity_type);
        $fields['fid']->setLabel(t('File ID'))
            ->setDescription(t('The file ID.'));
        $fields['uuid']->setDescription(t('The file UUID.'));
        $fields['langcode']->setLabel(t('Language code'))
            ->setDescription(t('The file language code.'));
        $fields['uid']->setDescription(t('The user ID of the file.'));
        $fields['filename'] = BaseFieldDefinition::create('string')->setLabel(t('Filename'))
            ->setDescription(t('Name of the file with no path components.'));
        $fields['uri'] = BaseFieldDefinition::create('file_uri')->setLabel(t('URI'))
            ->setDescription(t('The URI to access the file (either local or remote).'))
            ->setSetting('max_length', 255)
            ->setSetting('case_sensitive', TRUE)
            ->addConstraint('FileUriUnique');
        $fields['filemime'] = BaseFieldDefinition::create('string')->setLabel(t('File MIME type'))
            ->setSetting('is_ascii', TRUE)
            ->setDescription(t("The file's MIME type."));
        $fields['filesize'] = BaseFieldDefinition::create('integer')->setLabel(t('File size'))
            ->setDescription(t('The size of the file in bytes.'))
            ->setSetting('unsigned', TRUE)
            ->setSetting('size', 'big');
        $fields['status'] = BaseFieldDefinition::create('boolean')->setLabel(t('Status'))
            ->setDescription(t('The status of the file, temporary (FALSE) and permanent (TRUE).'))
            ->setDefaultValue(FALSE);
        $fields['created'] = BaseFieldDefinition::create('created')->setLabel(t('Created'))
            ->setDescription(t('The timestamp that the file was created.'));
        $fields['changed'] = BaseFieldDefinition::create('changed')->setLabel(t('Changed'))
            ->setDescription(t('The timestamp that the file was last changed.'));
        return $fields;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function getDefaultEntityOwner() {
        return NULL;
    }
    
    /**
     * {@inheritdoc}
     */
    protected function invalidateTagsOnSave($update) {
        $tags = $this->getListCacheTagsToInvalidate();
        // Always invalidate the 404 or 403 response cache because while files do
        // not have a canonical URL as such, they may be served via routes such as
        // private files.
        // Creating or updating an entity may change a cached 403 or 404 response.
        $tags = Cache::mergeTags($tags, [
            '4xx-response',
        ]);
        if ($update) {
            $tags = Cache::mergeTags($tags, $this->getCacheTagsToInvalidate());
        }
        Cache::invalidateTags($tags);
    }

}