FilterThemeHooks.php

<?php

namespace Drupal\filter\Hook;

use Drupal\Core\Hook\Attribute\Hook;
use Drupal\Core\Template\Attribute;

/**
 * Theme hooks for filter.
 */
class FilterThemeHooks {
  
  /**
   * Implements hook_theme().
   */
  public function theme() : array {
    return [
      'filter_tips' => [
        'variables' => [
          'tips' => NULL,
          'long' => FALSE,
        ],
        'initial preprocess' => static::class . ':preprocessFilterTips',
      ],
      'text_format_wrapper' => [
        'variables' => [
          'children' => NULL,
          'description' => NULL,
          'attributes' => [],
        ],
        'initial preprocess' => static::class . ':preprocessTextFormatWrapper',
      ],
      'filter_guidelines' => [
        'variables' => [
          'format' => NULL,
        ],
        'initial preprocess' => static::class . ':preprocessFilterGuidelines',
      ],
      'filter_caption' => [
        'variables' => [
          'node' => NULL,
          'tag' => NULL,
          'caption' => NULL,
          'classes' => NULL,
        ],
      ],
    ];
  }
  
  /**
   * Prepares variables for text format guideline templates.
   *
   * Default template: filter-guidelines.html.twig.
   *
   * @param array $variables
   *   An associative array containing:
   *   - format: An object representing a text format.
   */
  public function preprocessFilterGuidelines(array &$variables) : void {
    $format = $variables['format'];
    $variables['tips'] = [
      '#theme' => 'filter_tips',
      '#tips' => _filter_tips($format->id(), FALSE),
    ];
    // Add format id for filter.js.
    $variables['attributes']['data-drupal-format-id'] = $format->id();
  }
  
  /**
   * Prepares variables for text format wrapper templates.
   *
   * Default template: text-format-wrapper.html.twig.
   *
   * @param array $variables
   *   An associative array containing:
   *   - attributes: An associative array containing properties of the element.
   */
  public function preprocessTextFormatWrapper(array &$variables) : void {
    $variables['aria_description'] = FALSE;
    // Add element class and id for screen readers.
    if (isset($variables['attributes']['aria-describedby'])) {
      $variables['aria_description'] = TRUE;
      $variables['attributes']['id'] = $variables['attributes']['aria-describedby'];
      // Remove aria-describedby attribute as it shouldn't be visible here.
      unset($variables['attributes']['aria-describedby']);
    }
  }
  
  /**
   * Prepares variables for filter tips templates.
   *
   * Default template: filter-tips.html.twig.
   *
   * @param array $variables
   *   An associative array containing:
   *   - tips: An array containing descriptions and a CSS ID in the form of
   *     'module-name/filter-id' (only used when $long is TRUE) for each
   *     filter in one or more text formats. Example:
   *     @code
   *       [
   *         'Full HTML' => [
   *           0 => [
   *             'tip' => 'Web page addresses and email addresses turn into links automatically.',
   *             'id' => 'filter/2',
   *           ],
   *         ],
   *       ];
   *     @endcode
   *   - long: (optional) Whether the passed-in filter tips contain extended
   *     explanations, i.e. intended to be output on the path 'filter/tips'
   *     (TRUE), or are in a short format, i.e. suitable to be displayed below a
   *     form element. Defaults to FALSE.
   */
  public function preprocessFilterTips(array &$variables) : void {
    $tips = $variables['tips'];
    foreach ($variables['tips'] as $name => $tip_list) {
      foreach ($tip_list as $tip_key => $tip) {
        $tip_list[$tip_key]['attributes'] = new Attribute();
      }
      $variables['tips'][$name] = [
        'attributes' => new Attribute(),
        'name' => $name,
        'list' => $tip_list,
      ];
    }
    $variables['multiple'] = count($tips) > 1;
  }

}