Chris@0: <?php
Chris@0: 
Chris@0: namespace Drupal\contextual\Element;
Chris@0: 
Chris@17: use Drupal\Component\Utility\Crypt;
Chris@17: use Drupal\Core\Site\Settings;
Chris@0: use Drupal\Core\Template\Attribute;
Chris@0: use Drupal\Core\Render\Element\RenderElement;
Chris@17: use Drupal\Component\Render\FormattableMarkup;
Chris@0: 
Chris@0: /**
Chris@0:  * Provides a contextual_links_placeholder element.
Chris@0:  *
Chris@0:  * @RenderElement("contextual_links_placeholder")
Chris@0:  */
Chris@0: class ContextualLinksPlaceholder extends RenderElement {
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function getInfo() {
Chris@0:     $class = get_class($this);
Chris@0:     return [
Chris@0:       '#pre_render' => [
Chris@0:         [$class, 'preRenderPlaceholder'],
Chris@0:       ],
Chris@0:       '#id' => NULL,
Chris@0:     ];
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * Pre-render callback: Renders a contextual links placeholder into #markup.
Chris@0:    *
Chris@0:    * Renders an empty (hence invisible) placeholder div with a data-attribute
Chris@0:    * that contains an identifier ("contextual id"), which allows the JavaScript
Chris@0:    * of the drupal.contextual-links library to dynamically render contextual
Chris@0:    * links.
Chris@0:    *
Chris@0:    * @param array $element
Chris@0:    *   A structured array with #id containing a "contextual id".
Chris@0:    *
Chris@0:    * @return array
Chris@0:    *   The passed-in element with a contextual link placeholder in '#markup'.
Chris@0:    *
Chris@0:    * @see _contextual_links_to_id()
Chris@0:    */
Chris@0:   public static function preRenderPlaceholder(array $element) {
Chris@17:     $token = Crypt::hmacBase64($element['#id'], Settings::getHashSalt() . \Drupal::service('private_key')->get());
Chris@17:     $attribute = new Attribute([
Chris@17:       'data-contextual-id' => $element['#id'],
Chris@17:       'data-contextual-token' => $token,
Chris@17:     ]);
Chris@17:     $element['#markup'] = new FormattableMarkup('<div@attributes></div>', ['@attributes' => $attribute]);
Chris@0: 
Chris@0:     return $element;
Chris@0:   }
Chris@0: 
Chris@0: }