ezcontent-8.x-dev/modules/ezcontent_paragraphs/modules/ezcontent_cards_gallery/ezcontent_cards_gallery.module

<?php

/**
 * @file
 * Module file for ezcontent_cards_gallery.
 */

use Drupal\Component\Utility\Crypt;
use Drupal\Core\Url;

/**
 * Implements hook_preprocess_HOOK().
 */
function ezcontent_cards_gallery_preprocess_paragraph__cards_gallery(&$variables) {
  $variables['#attached']['library'][] = 'ezcontent_cards_gallery/ezcontent_cards_gallery_css';
}

/**
 * Implements hook_theme().
 */
function ezcontent_cards_gallery_theme($existing, $type, $theme, $path) {
  return [
    'ezcontent_colorbox_view_mode_formatter' => [
      'variables' => [
        'item' => NULL,
        'content' => NULL,
        'modal' => NULL,
        'item_attributes' => NULL,
        'entity' => NULL,
        'field_name' => NULL,
        'settings' => NULL,
      ],
    ],
  ];
}

/**
 * Implements hook_preprocess_HOOK().
 */
function ezcontent_cards_gallery_preprocess_ezcontent_colorbox_view_mode_formatter(&$variables) {
  static $gallery_token = NULL;

  /** @var \Drupal\Core\Entity\EntityInterface $item */
  $item = $variables['item'];
  /** @var \Drupal\Core\Entity\EntityInterface $entity */
  $entity = $variables['entity'];
  $field_name = $variables['field_name'];
  $settings = $variables['settings'];

  $config = \Drupal::config('colorbox.settings');

  // Build the gallery id.
  $entity_type = $entity->getEntityTypeId();
  $entity_bundle = $entity->bundle();
  $id = $entity->id();
  $entity_id = !empty($id) ? $entity_bundle . '-' . $id : 'entity-id';

  switch ($settings['colorbox_gallery']) {
    case 'post':
      $gallery_id = 'gallery-' . $entity_id;
      break;

    case 'page':
      $gallery_id = 'gallery-all';
      break;

    case 'field_post':
      $gallery_id = 'gallery-' . $entity_id . '-' . $field_name;
      break;

    case 'field_page':
      $gallery_id = 'gallery-' . $field_name;
      break;

    case 'custom':
      $token_service = \Drupal::token();
      $gallery_id = $token_service->replace($settings['colorbox_gallery_custom'],
        [$entity_type => $entity, 'entity' => $item], ['clear' => TRUE]);
      break;

    default:
      $gallery_id = '';
  }

  // If gallery id is not empty add unique per-request token to avoid
  // images being added manually to galleries.
  if (!empty($gallery_id) && $config->get('advanced.unique_token')) {
    // Check if gallery token has already been set, we need to reuse
    // the token for the whole request.
    if ($gallery_token === NULL) {
      // We use a short token since randomness is not critical.
      $gallery_token = Crypt::randomBytesBase64(8);
    }
    $gallery_id = $gallery_id . '-' . $gallery_token;
  }
  $variables['url'] = NULL;
  $item_type = $item->getEntityTypeId();
  if ($item_type === 'paragraph') {
    $variables['url'] = Url::fromRoute('ezcontent_paragraphs.display')
      ->setRouteParameters(
        [
          'paragraph' => $item->id(),
          'view_mode' => $variables['modal']['#view_mode'],
        ]
      );
  }
  $variables['attributes']['title'] = isset($entity->field_title) && $entity->field_title->value ? $entity->field_title->value : $entity->getParentEntity()->getTitle();
  $variables['attributes']['data-colorbox-gallery'] = $gallery_id;
  $variables['attributes']['class'] = ['colorbox'];
}