islandora_tokens.module

<?php

/**
 * @file
 * Provide tokens for Repository Item Thumbnail Image URL and Alternative Text.
 *
 * @todo:
 * - Add tokens for media-service-file:url, media-service-file:alt, media-original-file:alt, media-original-file:mimetype
 */

use Drupal\islandora\IslandoraUtils;
use Drupal\Core\Render\BubbleableMetadata;

/**
 * Implements hook_token_info().
 */
function islandora_tokens_token_info() {

  $info['tokens']['node']['media-thumbnail-image:url'] = [
    'name' => t('Media: Thumbnail Image URL.'),
    'description' => t('URL of Thumbnail Image associated with Islandora Object via Media.'),
  ];

  $info['tokens']['node']['media-thumbnail-image:alt'] = [
    'name' => t('Alternative text for Media: Thumbnail Image.'),
    'description' => t('Alternative text for Thumbnail Image associated with Islandora Object via Media.'),
  ];

  // Deprecated in favour if hyphenated version.
  $info['tokens']['node']['media_thumbnail_image:url'] = [
    'name' => t('Media: Thumbnail Image URL.'),
    'description' => t('Deprecated: URL of Thumbnail Image associated with Islandora Object via Media.'),
  ];

  // Deprecated in favour if hyphenated version.
  $info['tokens']['node']['media_thumbnail_image:alt'] = [
    'name' => t('Alternative text for Media: Thumbnail Image.'),
    'description' => t('Deprecated: Alternative text for Thumbnail Image associated with Islandora Object via Media.'),
  ];

  return $info;
}

/**
 * Implements hook_tokens().
 */
function islandora_tokens_tokens($type, $tokens, array $data, array $options, \Drupal\Core\Render\BubbleableMetadata $bubbleable_metadata) {
  $replacements = [];

  if ($type == 'node' && !empty($data['node'])) {
    if (!is_array($tokens) || empty($tokens)) {
      \Drupal::logger('islandora_tokens')
        ->alert('Tokens not correct format: @tokens', [
          '@tokens' => print_r($tokens, 1),
        ]);
      return;
    }

    $islandoraUtils = \Drupal::service('islandora.utils');

    foreach ($tokens as $name => $original) {
      switch ($name) {

        case 'media-thumbnail-image:url':
        case 'media_thumbnail_image:url':
          $term = $islandoraUtils->getTermForUri('http://pcdm.org/use#ThumbnailImage');
          $media = $islandoraUtils->getMediaWithTerm($data['node'], $term);
          // Is there media?
          // @todo: is this single or multiple?
          if ($media) {
            $file = islandora_tokens_image_from_media($media);
            if (!empty($file)) {
              $url = $file->getFileUri();
              $replacements[$original] = $url;
            }
          }
          break;

        case 'media-thumbnail-image:alt':
        case 'media_thumbnail_image:alt':
          $alt = '';
          $term = $islandoraUtils->getTermForUri('http://pcdm.org/use#ThumbnailImage');
          $media = $islandoraUtils->getMediaWithTerm($data['node'], $term);
          // Is there media?
          // @todo: is this single or multiple?
          if ($media) {
            // Is the media an image?
            if (isset($media->field_media_image)) {
              $alt = $media->field_media_image[0]->alt;
            }
          }
          // @todo: get alt from original or service file, if thumbnail alt is empty.
          $replacements[$original] = $alt;
          break;
      }
    }
  }

  return $replacements;
}

/**
 * Get File referenced by given Media.
 *
 * @todo: Add to IslandoraUtils?
 * @todo: Had to remove typehint MediaInterface from function.
 *
 * @param \Drupal\media\MediaInterface $media
 *   The Media to operate on.
 *
 * @return mixed
 *   \Drupal\file\FileInterface on success, NULL otherwise.
 */
function islandora_tokens_image_from_media($media) {
  $files = [];
  if ($media->hasField('field_media_image')) {
    $files = $media->get('field_media_image')->referencedEntities();
  }
  return !empty($files) ? reset($files) : NULL;
}