class FilterBase

abstract class FilterBase extends PluginBase implements FilterInterface {
  
  /**
   * The name of the provider that owns this filter.
   *
   * @var string
   */
  public $provider;
  
  /**
   * A Boolean indicating whether this filter is enabled.
   *
   * @var bool
   */
  public $status = FALSE;
  
  /**
   * The weight of this filter compared to others in a filter collection.
   *
   * @var int
   */
  public $weight = 0;
  
  /**
   * An associative array containing the configured settings of this filter.
   *
   * @var array
   */
  public $settings = [];
  
  /**
   * {@inheritdoc}
   */
  public function __construct(array $configuration, $plugin_id, $plugin_definition) {
    parent::__construct($configuration, $plugin_id, $plugin_definition);
    $this->provider = $this->pluginDefinition['provider'];
    $this->setConfiguration($configuration);
  }
  
  /**
   * {@inheritdoc}
   */
  public function setConfiguration(array $configuration) {
    if (isset($configuration['status'])) {
      $this->status = (bool) $configuration['status'];
    }
    if (isset($configuration['weight'])) {
      $this->weight = (int) $configuration['weight'];
    }
    if (isset($configuration['settings'])) {
      $this->settings = (array) $configuration['settings'];
    }
    return $this;
  }
  
  /**
   * {@inheritdoc}
   */
  public function getConfiguration() {
    return [
      'id' => $this->getPluginId(),
      'provider' => $this->pluginDefinition['provider'],
      'status' => $this->status,
      'weight' => $this->weight,
      'settings' => $this->settings,
    ];
  }
  
  /**
   * {@inheritdoc}
   */
  public function defaultConfiguration() {
    return [
      'provider' => $this->pluginDefinition['provider'],
      'status' => FALSE,
      'weight' => $this->pluginDefinition['weight'] ?: 0,
      'settings' => $this->pluginDefinition['settings'],
    ];
  }
  
  /**
   * {@inheritdoc}
   */
  public function calculateDependencies() {
    return [];
  }
  
  /**
   * {@inheritdoc}
   */
  public function getType() {
    return $this->pluginDefinition['type'];
  }
  
  /**
   * {@inheritdoc}
   */
  public function getLabel() {
    return $this->pluginDefinition['title'];
  }
  
  /**
   * {@inheritdoc}
   */
  public function getDescription() {
    return $this->pluginDefinition['description'];
  }
  
  /**
   * {@inheritdoc}
   */
  public function settingsForm(array $form, FormStateInterface $form_state) {
    // Implementations should work with and return $form. Returning an empty
    // array here allows the text format administration form to identify whether
    // the filter plugin has any settings form elements.
    return [];
  }
  
  /**
   * {@inheritdoc}
   */
  public function prepare($text, $langcode) {
    return $text;
  }
  
  /**
   * {@inheritdoc}
   */
  public function getHTMLRestrictions() {
    return FALSE;
  }
  
  /**
   * {@inheritdoc}
   */
  public function tips($long = FALSE) {
  }

}