v1/web/modules/contrib/advagg/advagg_mod/advagg_mod.module

<?php

/**
 * @file
 * Advanced aggregation modifier module.
 */

use Drupal\advagg\Asset\AssetOptimizer;

/**
 * Implements hook_js_alter().
 */
function advagg_mod_js_alter(&$js) {
  if (!advagg_enabled()) {
    return;
  }
  $config = \Drupal::config('advagg_mod.settings');
  // Use the current file system path for advagg_mod.
  $module_path = \Drupal::service('extension.list.module')->getPath('advagg_mod');
  if (isset($js[$module_path . '/js/loadCSS.js'])) {
    if ($config->get('css_defer_js_code') === 4) {
      $js[$module_path . '/js/loadCSS.js']['type'] = 'external';
      $js[$module_path . '/js/loadCSS.js']['data'] = '//cdn.rawgit.com/filamentgroup/loadCSS/master/src/loadCSS.js';
      $js[$module_path . '/js/cssrelpreload.js']['type'] = 'external';
      $js[$module_path . '/js/cssrelpreload.js']['data'] = '//cdn.rawgit.com/filamentgroup/loadCSS/master/src/cssrelpreload.js';
    }
  }

  // Change sort order so aggregates do not get split up.
  if ($config->get('js_adjust_sort_external') || $config->get('js_adjust_sort_browsers')) {
    advagg_mod_sort_css_js($js, 'js');
  }

  // Force all JS to be preprocessed.
  if ($config->get('js_preprocess')) {
    foreach ($js as $path => &$values) {
      // However CKEditor must not be combined or errors *will* occur.
      if ($path == 'core/assets/vendor/ckeditor/ckeditor.js') {
        continue;
      }
      $values['preprocess'] = TRUE;
    }
    unset($values);
  }

  // Move all async JS to the header.
  if ($config->get('js_async_in_header')) {
    foreach ($js as &$values) {
      // Skip if not file or external.
      if ($values['type'] !== 'file' && $values['type'] !== 'external') {
        continue;
      }
      // Skip if not async.
      if (!$config->get('js_async') && empty($values['async']) && empty($values['attributes']['async'])) {
        continue;
      }

      // Move to the header with a group of 1000.
      $values['scope'] = 'header';
      $values['group'] = 1000;
    }
    unset($values);
  }
}

/**
 * Implements hook_css_alter().
 */
function advagg_mod_css_alter(&$css) {
  if (!advagg_enabled()) {
    return;
  }
  $config = \Drupal::config('advagg_mod.settings');
  if ($config->get('css_adjust_sort_external') || $config->get('css_adjust_sort_browsers')) {
    advagg_mod_sort_css_js($css, 'css');
  }

  // Force all CSS to be preprocessed.
  if ($config->get('css_preprocess')) {
    foreach ($css as &$values) {
      $values['preprocess'] = TRUE;
    }
    unset($values);
  }
}

/**
 * Implements hook_page_attachments_alter().
 */
function advagg_mod_page_attachments_alter(array &$page) {
  if (advagg_mod_css_defer_active()) {
    $page['#attached']['library'][] = 'advagg_mod/css_defer';
  }
}

/**
 * Rearrange CSS/JS so that aggregates are better grouped.
 *
 * This can move all external assets to the top, thus in one group.
 * This can move all browser conditional assets together.
 *
 * @param array $assets
 *   The CSS or JS array.
 * @param string $type
 *   String: css or js.
 */
function advagg_mod_sort_css_js(array &$assets, $type) {
  $config = \Drupal::config('advagg_mod.settings');
  if ($config->get($type . '_adjust_sort_external')) {
    // Find all external items.
    $external = [];
    $group = NULL;
    $weight = NULL;
    foreach ($assets as $key => $value) {
      // Set values if not set.
      if (is_null($group)) {
        $group = $value['group'];
      }
      if (is_null($weight)) {
        $weight = $value['weight'];
      }

      // Find "lightest" item.
      if ($value['group'] < $group) {
        $group = $value['group'];
      }
      if ($value['weight'] < $weight) {
        $weight = $value['weight'];
      }

      if (!empty($value['type']) && $value['type'] === 'external' && empty($value['movable'])) {
        $external[$key] = $value;
        unset($assets[$key]);
      }
    }
    // Sort the array so that it appears in the correct order.
    AssetOptimizer::sortStable($external);

    // Group all external together.
    $offset = 0.0001;
    $weight -= 1;
    $group -= 10;
    $found_jquery = FALSE;
    foreach ($external as $key => $value) {

      // If bootstrap is used, it must be loaded after jquery. Don't move
      // bootstrap if jquery is not above it.
      if ($key == 'assets/vendor/jquery/jquery.min.js') {
        $found_jquery = TRUE;
      }
      if (!$found_jquery && (strpos($value['data'], 'bootstrap.min.js') !== FALSE || strpos($value['data'], 'bootstrap.js') !== FALSE)) {
        $assets[$key] = $value;
        continue;
      }
      $value['group'] = $group;
      $value['weight'] = $weight;
      $weight += $offset;
      $assets[$key] = $value;
    }
  }

  if ($config->get($type . '_adjust_sort_browsers')) {
    // Get a list of browsers.
    $browsers_list = [];
    foreach ($assets as $key => $value) {
      if (isset($value['browsers']['IE']) && $value['browsers']['IE'] !== TRUE) {
        $browsers_list['IE'][] = $value['browsers']['IE'];
      }
    }

    // Group browsers CSS together.
    if (isset($browsers_list['IE'])) {
      $browsers_list['IE'] = array_values(array_unique($browsers_list['IE']));
      foreach ($browsers_list['IE'] as $browser) {
        $browsers = [];
        $group = NULL;
        $weight = NULL;
        foreach ($assets as $key => $value) {
          if (isset($value['browsers']['IE']) && $browser === $value['browsers']['IE']) {
            // Set values if not set.
            if (is_null($group)) {
              $group = $value['group'];
            }
            if (is_null($weight)) {
              $weight = $value['weight'];
            }

            // Find "heaviest" item.
            if ($value['group'] > $group) {
              $group = $value['group'];
            }
            if ($value['weight'] > $weight) {
              $weight = $value['weight'];
            }

            $browsers[$key] = $value;
            unset($assets[$key]);
          }
        }

        // Sort the array so that it appears in the correct order.
        AssetOptimizer::sortStable($browsers);

        // Group all browsers together.
        $offset = 0.0001;
        $group += 1000;
        foreach ($browsers as $key => $value) {
          if (isset($value['movable']) && empty($value['movable'])) {
            $assets[$key] = $value;
            continue;
          }
          $value['group'] = $group;
          $value['weight'] = $weight;
          $weight += $offset;
          $assets[$key] = $value;
        }
      }
    }
  }
}

/**
 * Determines whether css defering should be active for the current request.
 */
function advagg_mod_css_defer_active() {
  $config = \Drupal::config('advagg_mod.settings');
  if (!$config->get('css_defer')) {
    return FALSE;
  }
  $admin_route = \Drupal::service('router.admin_context')->isAdminRoute();
  if ($admin_route && !$config->get('css_defer_admin')) {
    return FALSE;
  }
  return TRUE;
}