class UnicornEditor

class UnicornEditor extends EditorBase {
  
  /**
   * {@inheritdoc}
   */
  public function getDefaultSettings() {
    return [
      'ponies_too' => TRUE,
    ];
  }
  
  /**
   * {@inheritdoc}
   */
  public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
    $form['ponies_too'] = [
      '#title' => $this->t('Pony mode'),
      '#type' => 'checkbox',
      '#default_value' => TRUE,
    ];
    $form_state->loadInclude('editor', 'admin.inc');
    $form['image_upload'] = editor_image_upload_settings_form($form_state->get('editor'));
    $form['image_upload']['#element_validate'][] = [
      $this,
      'validateImageUploadSettings',
    ];
    return $form;
  }
  
  /**
   * Render API callback: Image upload handler for confirmation form.
   *
   * This function is assigned as a #element_validate callback.
   *
   * Moves the text editor's image upload settings into $editor->image_upload.
   *
   * @see editor_image_upload_settings_form()
   */
  public function validateImageUploadSettings(array $element, FormStateInterface $form_state) {
    $settings =& $form_state->getValue([
      'editor',
      'settings',
      'image_upload',
    ]);
    $form_state->get('editor')
      ->setImageUploadSettings($settings);
    $form_state->unsetValue([
      'editor',
      'settings',
      'image_upload',
    ]);
  }
  
  /**
   * {@inheritdoc}
   */
  public function getJSSettings(EditorEntity $editor) {
    $js_settings = [];
    $settings = $editor->getSettings();
    if ($settings['ponies_too']) {
      $js_settings['ponyModeEnabled'] = TRUE;
    }
    return $js_settings;
  }
  
  /**
   * {@inheritdoc}
   */
  public function getLibraries(EditorEntity $editor) {
    return [
      'editor_test/unicorn',
    ];
  }

}