<?php

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

// Core hook implementations.
/**
 * Implements hook_js_alter().
 */
function advagg_mod_js_alter(&$js) {
  if (\Drupal::moduleHandler()->moduleExists('advagg') && !advagg_enabled()) {
    return;
  }
  $config = \Drupal::config('advagg_mod.settings');

  $css_defer = $config->get('css_defer');

  // Use the current file system path for advagg_mod.
  $module_path = drupal_get_path('module', 'advagg_mod');
  if (advagg_mod_css_defer_active() && isset($js[$module_path . '/js/loadCSS.js'])) {
    if ($css_defer == 3) {
      $js[$module_path . '/js/loadCSS.js']['scope'] = 'header';
      $js[$module_path . '/js/css_defer.js']['scope'] = 'header';
    }
    $css_defer_js_code = $config->get('css_defer_js_code');
    if ($css_defer_js_code == 0) {
      $js[$module_path . '/js/loadCSS.js']['inline'] = TRUE;
      $js[$module_path . '/js/css_defer.js']['inline'] = TRUE;
    }
    elseif ($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';
    }
  }

  // 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');
  }

  // Move JS to the footer.
  if ($config->get('js_footer')) {
    advagg_mod_js_move_to_footer($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;
      $values['cache'] = TRUE;
    }
    unset($values);
  }

  // Add the defer or the async tag to JS.
  advagg_mod_js_async_defer($js);

  // 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' && $values['type'] !== 'external') {
        continue;
      }
      // Skip if not async.
      if (empty($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 (\Drupal::moduleHandler()->moduleExists('advagg') && !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';
  }
}

// AdvAgg hook implementations.
/**
 * Implements hook_advagg_current_hooks_hash_array_alter().
 */
function advagg_mod_advagg_current_hooks_hash_array_alter(array &$aggregate_settings) {
  $aggregate_settings['variables']['advagg_mod'] = \Drupal::config('advagg_mod.settings')->get();
}

/**
 * Implements hook_advagg_asset_render_alter().
 */
function advagg_mod_advagg_asset_render_alter(&$assets, $render_type, $asset_type) {
  if (!advagg_enabled()) {
    return;
  }

  if ($render_type == 'html') {
    if ($asset_type == 'styles') {
      foreach ($assets as &$value) {
        if (!empty($value['#inline'])) {
          $value['#value'] = @file_get_contents($value['#attributes']['href']);
          if ($value['#value']) {
            unset($value['#attributes']['href']);
          }
        }
        elseif (advagg_mod_css_defer_active()) {
          // Skip prefetch links and inline styles.
          if ($value['#tag'] == 'style') {
            continue;
          }
          $value['#attributes']['class'][] = 'advagg-css-defer';
          $value['#noscript'] = TRUE;
        }
      }
      unset($value);
    }
    elseif ($asset_type == 'scripts' || $asset_type == 'scripts_bottom') {
      foreach ($assets as &$value) {
        if (!empty($value['#inline'])) {
          $value['#value'] = @file_get_contents($value['#attributes']['src']);
          if ($value['#value']) {
            unset($value['#attributes']['src']);
          }
        }
      }
    }
  }
}

/**
 * Implements hook_advagg_hooks_implemented_alter().
 */
function advagg_mod_advagg_hooks_implemented_alter(&$hooks, $all) {
  if ($all) {
    $hooks += [
      'advagg_mod_get_lists_alter' => [],
    ];
  }
}

/**
 * Implements hook_advagg_asset_path_alter().
 */
function advagg_mod_advagg_asset_path_alter(&$path, $extension) {
  if ($dir = rtrim(\Drupal::config('advagg_mod.settings')->get('unified_multisite_dir'), '/')) {
    if ($extension == 'js') {
      $path = $dir . '/js';
    }
    elseif ($extension == 'css') {
      $path = $dir . '/css';
    }
  }
}

// Helper Functions.
/**
 * Generate a list of rules and exceptions for js files.
 *
 * Controls no async/defer file list.
 *
 * @return array
 *   A multidimensional array.
 */
function advagg_mod_get_lists() {
  $lists = &drupal_static(__FUNCTION__);
  if (!isset($lists)) {
    // Do not defer/async list.
    $no_async_defer_list = [
      // Wistia js.
      '//fast.wistia.',
      // Maps.
      '//maps.googleapis.com',
      '//dev.virtualearth.net',
      '//api.maps.yahoo.com',
    ];
    $no_move = [
      '//cdn.rawgit.com/stubbornella/csslint/master/release/csslint.js',
    ];

    // Allow other modules to add/edit the above lists.
    // Call hook_advagg_mod_get_lists_alter().
    $lists = [
      $no_async_defer_list,
      $no_move,
    ];
    \Drupal::moduleHandler()->alter('advagg_mod_get_lists', $lists);
  }
  return $lists;
}

/**
 * Move JS to the footer.
 *
 * @param array $js
 *   JS array.
 */
function advagg_mod_js_move_to_footer(array &$js) {
  // Move all JS to the footer.
  $move_js_to_footer = \Drupal::config('advagg_mod.settings')->get('js_footer');
  $core_header_js = [
    'core/assets/vendor/modernizr/modernizr.min.js' => 0,
    'core/assets/vendor/html5shiv/html5shiv.min.js' => 0,
  ];

  foreach ($js as $key => &$values) {
    // Skip if a core header file and configured to do so.
    if ($move_js_to_footer == 3 && isset($core_header_js[$key])) {
      continue;
    }

    // Skip if the scope has been locked.
    if (!empty($values['scope_lock'])) {
      continue;
    }

    // If JS is not in the header decrease weight by 10000.
    if ($values['scope'] === 'header') {
      $values['weight'] -= 10000;
    }
    // If JS is already in the footer decrease weight by 10000.
    if ($values['scope'] !== 'footer') {
      $values['weight'] -= 10000;
    }
    $values['scope'] = 'footer';
  }
  unset($values);
}

/**
 * Add the defer and or the async tag to js.
 *
 * @param array $js
 *   JS array.
 */
function advagg_mod_js_async_defer(array &$js) {
  // Return early if this is disabled.
  $config = \Drupal::config('advagg_mod.settings');
  $defer = $config->get('js_defer');
  $async = $config->get('js_async');
  list($no_async_defer_list) = advagg_mod_get_lists();

  // Make all scripts defer and/or async.
  foreach ($js as $name => &$values) {
    $values['attributes'] = [];
    // Defer all scripts.
    if ($defer) {
      $values['attributes']['defer'] = TRUE;

      // Do not defer external scripts setting.
      if ($defer == 2 && $values['type'] === 'external') {
        unset($values['attributes']['defer']);
      }
    }

    // Async all scripts. On most browsers this will run instead of defer.
    // On some older browsers if defer is also set they will run that instead
    // if they don't support async.
    if ($async) {
      $values['attributes']['async'] = TRUE;
    }

    // No async defer list.
    foreach ($no_async_defer_list as $search_string) {
      if (strpos($name, $search_string) !== FALSE) {
        // Do not defer/async the loading this script.
        if ($defer) {
          unset($values['attributes']['async'], $values['attributes']['defer']);
        }
      }
    }
  }
  unset($values);
}

/**
 * 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'];
      }

      list(, $no_move) = advagg_mod_get_lists();
      if (!empty($value['type']) && $value['type'] === 'external' && !in_array($key, $no_move) && empty($value['movable'])) {
        $external[$key] = $value;
        unset($assets[$key]);
      }
    }
    // Sort the array so that it appears in the correct order.
    advagg_drupal_sort_css_js_stable($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.
        advagg_drupal_sort_css_js_stable($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;
}