baidu_analytics.module

<?php

/**
 * @file
 * Drupal Module: Baidu Analytics
 *
 * Adds the required Javascript to all your Drupal pages to allow tracking by
 * the Baidu Analytics statistics package.
 */
use Drupal\Component\Serialization\Json;
use Drupal\Component\Utility\Crypt;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Url;
/**
 * Define the default file extension list that should be tracked as download.
 */
define('BAIDU_ANALYTICS_TRACKFILES_EXTENSIONS', '7z|aac|arc|arj|asf|asx|avi|bin|csv|doc|exe|flv|gif|gz|gzip|hqx|jar|jpe?g|js|mp(2|3|4|e?g)|mov(ie)?|msi|msp|pdf|phps|png|ppt|qtm?|ra(m|r)?|sea|sit|tar|tgz|torrent|txt|wav|wma|wmv|wpd|xls|xml|z|zip');

/**
 * Define default path exclusion list to remove tracking from admin pages,
 * see http://drupal.org/node/34970 for more information.
 */
define('BAIDU_ANALYTICS_PAGES', "admin\nadmin/*\nbatch\nnode/add*\nnode/*/*\nuser/*/*");

/**
 * Define Asynchronous Tracker Code Library URL.
 */
define('BAIDU_ANALYTICS_ASYNC_LIBRARY_URL', 'hm.baidu.com/hm.js');

/**
 * Define Standard Tracker Code Library URL.
 */
define('BAIDU_ANALYTICS_STANDARD_LIBRARY_URL', 'hm.baidu.com/h.js');

/**
 * Implements hook_help().
 */
function baidu_analytics_help($route_name, \Drupal\Core\Routing\RouteMatchInterface $route_match) {
  switch ($route_name) {
    case 'help.page.baidu_analytics':
      $output = '<h3>' . t('About') . '</h3>';
      $output .= '<p>' . t('Baidu Analytics adds a web statistics tracking system to your website. This system incorporates numerous statistical features. For an extensive listing of these features see the <a href=":project">Baidu Analytics</a> project site. Beyond that, additional information can be found at the <a href=":documentation">Drupal - Baidu Analytics documentation</a>.', [':documentation' => 'https://www.drupal.org/node/2076737', ':project' => 'https://www.drupal.org/project/baidu_analytics']) . '</p>';
      $output .= '<h3>' . t('Uses') . '</h3>';
      $output .= '<dt>' . t('Configuring Baidu Analytics') . '</dt>';
      $output .= '<dd>' . t('All settings for this module can be found on the <a href=":ba_settings">Baidu Analytics settings</a> page. When entering the Baidu Analytics account number here, it will automatically add the required JavaScript to every page generated. The <em>General Settings</em> section on this page provides additional instruction about setting up tracking thru the Baidu account.', [':ba_settings' => Url::fromRoute('baidu_analytics.admin_settings_form')->toString()]) . '</dd>';
      $output .= '<dt>' . t('Additional features') . '</dt>';
      $output .= '<dd>' . t('The Baidu Analytics module offers a bit more than basic tracking. <em>Page Tracking</em> for instance allows you to provide a list of pages to track, or a list of pages not to track. Role and Link tracking features are also available. For a comprehensive discussion on the setup and use of its many feature see the <a href=":documentation">Drupal - Baidu Analytics documentation</a>.', [':documentation' => 'https://www.drupal.org/node/2076737']) . '</dd>';
      return $output;
    case 'baidu_analytics.admin_settings_form':
      return t('<a href="@btj_url">Baidu Analytics</a> is a free (registration required) website traffic and marketing effectiveness service.', array('@btj_url' => 'http://tongji.baidu.com/'));
  }
}

/**
 * Implements hook_page_attachments().
 */
function baidu_analytics_page_attachments(&$page) {
  $user = \Drupal::currentUser();
  $config = \Drupal::config('baidu_analytics.settings');
  // Get the web property ID for which the tracking code should be generated.
  $id = $config->get('baidu_analytics_account');
  $request = \Drupal::request();
  // Get page http status code for visibility filtering.
  $status = NULL;
  if ($exception = $request->attributes->get('exception')) {
    $status = $exception->getStatusCode();
  }
  $trackable_status_codes = array(
    '403', // Forbidden
    '404', // Not Found
  );

  // 1. Check if the Baidu account number has a value.
  // 2. Track page views based on visibility value.
  // 3. Check if we should track the currently active user's role.
  // 4. Ignore pages visibility filter for 404 or 403 status codes.
  if (!empty($id) && (_baidu_analytics_visibility_pages() || in_array($status, $trackable_status_codes)) && _baidu_analytics_visibility_user($user)) {

    // Allow user to override the scope for script inclusion in the page.
    $scope = $config->get('baidu_analytics_js_scope');
    // Select recommended scope depending on the type of code to generate.
    if ($scope == 'default') {
      if ($config->get('baidu_analytics_code_type') == 'standard') {
        // Standard code is recommended to be added in 'footer'.
        $scope = 'footer';
      }
      else {
        // Asynchronous code is recommended to be added in 'header'.
        $scope = 'header';
      }
    }

    // Add link tracking.
    $link_settings = array();
    if ($track_outbound = $config->get('baidu_analytics_trackoutbound')) {
      $link_settings['trackOutbound'] = $track_outbound;
    }
    if ($track_mailto = $config->get('baidu_analytics_trackmailto')) {
      $link_settings['trackMailto'] = $track_mailto;
    }
    if (($track_download = $config->get('baidu_analytics_trackfiles')) && ($trackfiles_extensions = $config->get('baidu_analytics_trackfiles_extensions'))) {
      $link_settings['trackDownload'] = $track_download;
      $link_settings['trackDownloadExtensions'] = $trackfiles_extensions;
    }

    if (!empty($link_settings)) {
      $page['#attached']['drupalSettings']['baidu_analytics'] = $link_settings;
      $page['#attached']['library'][] = 'baidu_analytics/baidu_analytics';
    }
    // Add messages tracking.
    $message_events = '';
    if ($message_types = $config->get('baidu_analytics_trackmessages')) {
      $message_types = array_values(array_filter($message_types));
      $status_heading = array(
        'status' => t('Status message'),
        'warning' => t('Warning message'),
        'error' => t('Error message'),
      );

      foreach (drupal_get_messages(NULL, FALSE) as $type => $messages) {
        // Track only the selected message types.
        if (in_array($type, $message_types)) {
          foreach ($messages as $message) {
            $message_events .= '_hmt.push(["_trackEvent", ' . Json::encode(t('Messages')) . ', ' . Json::encode($status_heading[$type]) . ', ' . Json::encode($status_heading[$type] . ': ' . strip_tags($message)) . ']);';
          }
        }
      }
    }

    // Site search tracking support.
    $url_custom = '';
    if (\Drupal::moduleHandler()->moduleExists('search') && $config->get('baidu_analytics_site_search') && (strpos(\Drupal::routeMatch()->getRouteName(), 'search.view') === 0) && $keys = ($request->query->has('keys') ? trim($request->get('keys')) : '')) {
      global $pager_total_items;
      $entity_id = \Drupal::routeMatch()->getParameter('entity')->id();
      // If there are results, include the keys and the total count.
      if ($pager_total_items != 0) {
        $url_custom = Url::fromRoute('search.view_' . $entity_id, [], ['query' => ['search' => $keys, 'total-results' => intval($pager_total_items[0])]])->toString();
      }
      else {
        // Make sure no results keys are included in the tracked URL.
        $url_custom = Url::fromRoute('search.view_' . $entity_id, [], ['query' => ['search' => 'no-results:' . $keys, 'cat' => 'no-results']])->toString();
      }
    }
    // If this node is translated from another one, pass the original instead.
    if (\Drupal::moduleHandler()->moduleExists('content_translation') && $config->get('baidu_analytics_translation_set')) {
      // Check we have a node object, it supports translation, and its
      // translated node ID (tnid) doesn't match its own node ID.
      if ($request->attributes->has('node')) {
        $node = $request->attributes->get('node');
        if ($node instanceof NodeInterface && \Drupal::entityManager()->getTranslationFromContext($node) !== $node->getUntranslated()) {
        $url_custom = Url::fromRoute('entity.node.canonical', ['node' => $node->id()], ['language' => $node->getUntranslated()->language()])->toString();
        }
      }
    }

    // Track access denied (403) and file not found (404) pages.
    $referer_uri = isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : '';
    $current_uri = $request->getRequestUri() == '' ? '/' : $request->getRequestUri();
    // Report a specific URL containing referer and current page URL.
    if ($status == '403') {
      $url_custom = "/403.html?page={$current_uri}&from={$referer_uri}";
    }
    elseif ($status == '404') {
      $url_custom = "/404.html?page={$current_uri}&from={$referer_uri}";
    }

    // Add any custom code snippets if specified.
    $codesnippet_before = $config->get('baidu_analytics_codesnippet_before');
    $codesnippet_after = $config->get('baidu_analytics_codesnippet_after');
    $baidu_analytics_custom_vars = $config->get('baidu_analytics_custom_var');
    $custom_var = '';
    for ($i = 1; $i < 6; $i++) {
      $custom_var_name = !empty($baidu_analytics_custom_vars['slots'][$i]['name']) ? $baidu_analytics_custom_vars['slots'][$i]['name'] : '';
      if (!empty($custom_var_name)) {
        $custom_var_value = !empty($baidu_analytics_custom_vars['slots'][$i]['value']) ? $baidu_analytics_custom_vars['slots'][$i]['value'] : '';
        $custom_var_scope = !empty($baidu_analytics_custom_vars['slots'][$i]['scope']) ? $baidu_analytics_custom_vars['slots'][$i]['scope'] : 3;

        $types = array();
        if ($request->attributes->has('node')) {
          $node = $request->attributes->get('node');
          if ($node instanceof NodeInterface) {
            $types += ['node' => $node];
          }
        }
        $custom_var_name = \Drupal::token()->replace($custom_var_name, $types, array('clear' => TRUE));
        $custom_var_value = \Drupal::token()->replace($custom_var_value, $types, array('clear' => TRUE));

        // Suppress empty custom names and/or variables.
        if (!Unicode::strlen(trim($custom_var_name)) || !Unicode::strlen(trim($custom_var_value))) {
          continue;
        }

        // The length of the string used for the 'name' and the one used for
        // the 'value' must not exceed 128 bytes after url encoding.
        $name_length = Unicode::strlenn(rawurlencode($custom_var_name));
        $tmp_value = rawurlencode($custom_var_value);
        $value_length = Unicode::strlen($tmp_value);
        if ($name_length + $value_length > 128) {
          // Trim value and remove fragments of url encoding.
          $tmp_value = rtrim(substr($tmp_value, 0, 127 - $name_length), '%0..9A..F');
          $custom_var_value = urldecode($tmp_value);
        }

        $custom_var_name = Json::encode($custom_var_name);
        $custom_var_value = Json::encode($custom_var_value);
        $custom_var .= "_hmt.push(['_setCustomVar', $i, $custom_var_name, $custom_var_value, $custom_var_scope]);";
      }
    }
    // Start putting together the javascript code to be inserted in the page.
    $script = 'var _hmt = _hmt || [];';
    $script .= '_hmt.push(["_setAccount", ' . Json::encode($id) . ']);';

    if (!empty($custom_var)) {
      $script .= $custom_var;
    }
    if (!empty($codesnippet_before)) {
      $script .= $codesnippet_before;
    }

    if (empty($url_custom)) {
      $script .= '_hmt.push(["_trackPageview"]);';
    }
    else {
      $script .= '_hmt.push(["_trackPageview", "' . $url_custom . '"]);';
    }
    if (!empty($message_events)) {
      $script .= $message_events;
    }
    if (!empty($codesnippet_after)) {
      $script .= $codesnippet_after;
    }
    // Determine which type of code should be used: async or standard.
    if ($config->get('baidu_analytics_code_type') == 'standard') {
      // Provide Standard BATC file URL on server if it is locally cached.
      if ($config->get('baidu_analytics_cache') && $library_tracker_url = _baidu_analytics_cache(BAIDU_ANALYTICS_STANDARD_LIBRARY_URL)) {
        // A dummy query-string is added to filenames, to gain control over
        // browser-caching. The string changes on every update or full cache
        // flush, forcing browsers to load a new copy of the files, as the
        // URL changed.
        $query_string = '?' . (\Drupal::state()->get('system.css_js_query_string') ?: '0');
        $library_tracker_url .= $query_string;
      }
      else {
        // If no cache is found, provide Standard Code Tracker library URL.
        $library_tracker_url = '//' . BAIDU_ANALYTICS_STANDARD_LIBRARY_URL . '?' . $id;
      }
      $script .= 'document.write(unescape("%3Cscript src=\'' . $library_tracker_url . "' type='text/javascript'%3E%3C/script%3E\"));";
    }
    else {
      // Provide Asynchronous BATC file URL on server if it is locally cached.
      if ($config->get('baidu_analytics_cache') && $library_tracker_url = _baidu_analytics_cache(BAIDU_ANALYTICS_ASYNC_LIBRARY_URL)) {
        // Add dummy query-string to filenames, same trick as the case above.
        $query_string = '?' . (\Drupal::state()->get('system.css_js_query_string') ?: '0');
        $library_tracker_url .= $query_string;
      }
      else {
        // If no cache is found, provide Asynchronous Code Tracker library URL.
        $library_tracker_url = '//' . BAIDU_ANALYTICS_ASYNC_LIBRARY_URL . '?' . $id;
      }
      // Asynchronous JavaScript tracking code.
      $script .= "(function() {var hm = document.createElement('script');hm.src = '{$library_tracker_url}';hm.type = 'text/javascript';var s = document.getElementsByTagName('script')[0];s.parentNode.insertBefore(hm, s);})()";
    }
    $page['#attached']['html_head'][] = [
      [
        '#tag' => 'script',
        '#value' => $script,
        '#scope' => $scope,
      ],
      'baidu_analytics_tracking_script'
    ];
  }
}

/**
 * Implements hook_field_extra_fields().
 */
function baidu_analytics_entity_extra_field_info() {
  $extra = array();
  $extra['user']['user']['form']['baidu_analytics'] = array(
    'label' => t('Baidu Analytics configuration'),
    'description' => t('Baidu Analytics module form element.'),
    'weight' => 3,
  );

  return $extra;
}

/**
 * Implements hook_form_FORM_ID_alter().
 *
 * Allow users to decide if tracking code will be added to pages or not.
 */
function baidu_analytics_form_user_form_alter(&$form, FormStateInterface $form_state, $form_id) {
  $config = \Drupal::config('baidu_analytics.settings');
  $account = $form_state->getFormObject()->getEntity();
  //$category = $form['#user_category'];

  if (\Drupal::currentUser()->hasPermission('opt-in or out of tracking') && ($visibility_user_account_mode = $config->get('baidu_analytics_custom')) != 0 && _baidu_analytics_visibility_roles($account)) {
    $account_data_baidu_analytics = \Drupal::service('user.data')->get('baidu_analytics', $account->id());
    $form['baidu_analytics'] = array(
      '#type' => 'details',
      '#title' => t('Baidu Analytics configuration'),
      '#weight' => 3,
      '#open' => TRUE,
    );

    switch ($visibility_user_account_mode) {
      case 1:
        $description = t('Users are tracked by default, but you are able to opt out.');
        break;

      case 2:
        $description = t('Users are <em>not</em> tracked by default, but you are able to opt in.');
        break;
    }

    // Disable tracking for visitors who have opted out from tracking via DNT
    // (Do-Not-Track) header.
    $disabled = FALSE;
    if ($config->get('baidu_analytics_privacy_donottrack') && !empty($_SERVER['HTTP_DNT'])) {
      $disabled = TRUE;

      // Override settings value.
      $account_data_baidu_analytics['baidu_analytics_custom'] = FALSE;

      $description .= '<span class="admin-disabled">';
      $description .= ' ' . t('You have opted out from tracking via browser privacy settings.');
      $description .= '</span>';
    }

    $form['baidu_analytics']['baidu_analytics_custom'] = array(
      '#type' => 'checkbox',
      '#title' => t('Enable user tracking'),
      '#description' => $description,
      '#default_value' => isset($account_data_baidu_analytics['baidu_analytics_custom']) ? $account_data_baidu_analytics['baidu_analytics_custom'] : ($visibility_user_account_mode == 1),
      '#disabled' => $disabled,
    );
    // hook_user_update() is missing in D8, add custom submit handler.
    $form['actions']['submit']['#submit'][] = 'baidu_analytics_user_profile_form_submit';
  }
}

/**
 * Submit callback for user profile form to save the Baidu Analytics setting.
 */
function baidu_analytics_user_profile_form_submit($form, FormStateInterface $form_state) {
  $account = $form_state->getFormObject()->getEntity();
  if ($account->id() && $form_state->hasValue('baidu_analytics_custom')) {
    \Drupal::service('user.data')->set('baidu_analytics', $account->id(), 'baidu_analytics_custom', (int) $form_state->getValue('baidu_analytics_custom'));
  }
}

/**
 * Implements hook_cron().
 */
function baidu_analytics_cron() {
  $config = \Drupal::config('baidu_analytics.settings');
  // Regenerate the tracking code file every day.
  if ($config->get('baidu_analytics_cache') && REQUEST_TIME - $config->get('baidu_analytics_last_cache') >= 86400) {
    // Depending on the type of code selected, provide the correct tracker url.
    if ($config->get('baidu_analytics_code_type') == 'standard') {
      $library_tracker_url = BAIDU_ANALYTICS_STANDARD_LIBRARY_URL;
    }
    else {
      $library_tracker_url = BAIDU_ANALYTICS_ASYNC_LIBRARY_URL;
    }
    _baidu_analytics_cache($library_tracker_url, TRUE);
    \Drupal::configFactory()->getEditable('baidu_analytics.settings')->set('baidu_analytics_last_cache', REQUEST_TIME)->save();
  }
}

/**
 * Helper function for grabbing search keys. Function is missing in D7.
 *
 * http://api.drupal.org/api/function/search_get_keys/6
 */
function baidu_analytics_search_get_keys() {
  static $return;
  if (!isset($return)) {
    // Extract keys as remainder of path
    // Note: support old GET format of searches for existing links.
    $path = explode('/', $_GET['q'], 3);
    $keys = empty($_REQUEST['keys']) ? '' : $_REQUEST['keys'];
    $return = count($path) == 3 ? $path[2] : $keys;
  }
  return $return;
}

/**
 * Download/Synchronize/Cache tracking code file locally.
 *
 * @param string $location
 *   The full URL to the external javascript file.
 * @param bool $sync_cached_file
 *   Synchronize tracking code and update if remote file have changed.
 *
 * @return mixed
 *   The path to the local javascript file on success, boolean FALSE on failure.
 */
function _baidu_analytics_cache($location, $sync_cached_file = FALSE) {
  $config = \Drupal::config('baidu_analytics.settings');
  $path = 'public://baidu_analytics';
  $baidu_analytics_account = $config->get('baidu_analytics_account');
  // Use a tracker specific cache file to allow multiple codes on same site.
  $tracker_hash = \Drupal\Component\Utility\Unicode::substr($baidu_analytics_account, 0, 7);
  $file_destination = $path . '/' . (!empty($tracker_hash) ? $tracker_hash . '-' : '') . basename($location);

  if (!file_exists($file_destination) || $sync_cached_file) {
    global $base_url;
    // Get current server's protocol to match with the request.
    $protocol = (!empty($_SERVER['HTTPS']) && $_SERVER['HTTPS'] !== 'off' || $_SERVER['SERVER_PORT'] == 443) ? 'https://' : 'http://';
    $location = $protocol . $location . '?' . $baidu_analytics_account;
    try {
      $response = \Drupal::httpClient()->get($location, [
        'headers' => [
          'referer' => $base_url,
        ],
      ]);
      $data = $response->getBody(TRUE);
      if (file_exists($file_destination)) {
        // Synchronize tracking code and and replace local file if outdated.
        $data_hash_local = Crypt::hashBase64(file_get_contents($file_destination));
        $data_hash_remote = Crypt::hashBase64($data);
        // Check that the files directory is writable.
        if ($data_hash_local != $data_hash_remote && file_prepare_directory($path)) {
          // Save updated tracking code file to disk.
          file_unmanaged_save_data($data, $file_destination, FILE_EXISTS_REPLACE);
          \Drupal::logger('baidu_analytics')->info('Locally cached tracking code file has been updated.');

          // Change query-strings on css/js files to enforce reload for all.
          _drupal_flush_css_js();
        }
      }
      else {
        // Check that the files directory is writable.
        if (file_prepare_directory($path, FILE_CREATE_DIRECTORY)) {
          // There is no need to flush JS here as core refreshes JS caches
          // automatically, if new files are added.
          file_unmanaged_save_data($data, $file_destination, FILE_EXISTS_REPLACE);
          \Drupal::logger('baidu_analytics')->info('Locally cached tracking code file has been saved.');

          // Return the local JS file path.
          return file_url_transform_relative(file_create_url($file_destination));
        }
      }
    }
    catch (RequestException $exception) {
      watchdog_exception('baidu_analytics', $exception);
    }
  }
  else {
    // Return the local JS file path.
    return file_url_transform_relative(file_create_url($file_destination));
  }
}

/**
 * Delete cached files and directory.
 */
function baidu_analytics_clear_js_cache() {
  $path = 'public://baidu_analytics';
  if (file_prepare_directory($path)) {
    file_scan_directory($path, '/.*/', array('callback' => 'file_unmanaged_delete'));
    \Drupal::service("file_system")->rmdir($path);

    // Change query-strings on css/js files to enforce reload for all users.
    _drupal_flush_css_js();

    \Drupal::logger('baidu_analytics')->info('Local cache has been purged.', array());
  }
}

/**
 * Tracking visibility check for an user object.
 *
 * @param object $account
 *   A user object containing an array of roles to check.
 *
 * @return bool
 *   A decision on if the current user is being tracked by Baidu Analytics.
 */
function _baidu_analytics_visibility_user($account) {

  $enabled = FALSE;

  // Is current user a member of a role that should be tracked?
  if (_baidu_analytics_visibility_header($account) && _baidu_analytics_visibility_roles($account)) {

    // Use the user's block visibility setting, if necessary.
    if (($custom = \Drupal::config('baidu_analytics.settings')->get('baidu_analytics_custom')) != 0) {
      if ($account->uid && isset($account->data['baidu_analytics']['custom'])) {
        $enabled = $account->data['baidu_analytics']['custom'];
      }
      else {
        $enabled = ($custom == 1);
      }
    }
    else {
      $enabled = TRUE;
    }
  }

  return $enabled;
}

/**
 * Helper function to check if tracking code should display for current roles.
 *
 * Based on visibility setting this function returns TRUE if BA code should be
 * added for the current role and otherwise FALSE.
 */
function _baidu_analytics_visibility_roles($account) {

  $visibility = \Drupal::config('baidu_analytics.settings')->get('baidu_analytics_visibility_roles');
  $enabled = $visibility;
  $roles = array_filter(\Drupal::config('baidu_analytics.settings')->get('baidu_analytics_roles'));

  if (count($roles) > 0) {
    // One or more roles are selected.
    foreach (array_values($account->getRoles()) as $user_role) {
      // Is the current user a member of one of these roles?
      if (in_array($user_role, $roles)) {
        // Current user is a member of a role that should be tracked or
        // excluded from tracking.
        $enabled = !$visibility;
        break;
      }
    }
  }
  else {
    // No role is selected for tracking, therefore all roles should be tracked.
    $enabled = TRUE;
  }

  return $enabled;
}

/**
 * Helper function to check if tracking code should display for current page.
 *
 * Based on visibility setting this function returns TRUE if BA code should be
 * added to the current page and otherwise FALSE.
 */
function _baidu_analytics_visibility_pages() {
  $config = \Drupal::config('baidu_analytics.settings');
  static $page_match;

  // Cache visibility result if function is called more than once.
  if (!isset($page_match)) {

    $visibility = $config->get('baidu_analytics_visibility_pages');
    $setting_pages = $config->get('baidu_analytics_pages');

    // Match path if necessary.
    if (!empty($setting_pages)) {
      // Convert path to lowercase. This allows comparison of the same path
      // with different case. Ex: /Page, /page, /PAGE.
      $pages = \Drupal\Component\Utility\Unicode::strtolower($setting_pages);
      if ($visibility < 2) {
        $current_path = \Drupal::service('path.current')->getPath();
        $path = \Drupal::service('path.alias_manager')->getAliasByPath($current_path);
        // Convert the Drupal path to lowercase.
        $path = \Drupal\Component\Utility\Unicode::strtolower($path);
        // Compare the lowercase internal and lowercase path alias (if any).
        $page_match = \Drupal::service('path.matcher')->matchPath($path, $pages);
        if ($path != $current_path) {
          $page_match = $page_match || \Drupal::service('path.matcher')->matchPath($current_path, $pages);
        }
        // When $visibility has a value of 0, the tracking code is displayed on
        // all pages except those listed in $pages. When set to 1, it
        // is displayed only on those pages listed in $pages.
        $page_match = !($visibility xor $page_match);
      }
      elseif (\Drupal::moduleHandler()->moduleExists('php')) {
        $page_match = php_eval($setting_pages);
      }
      else {
        $page_match = FALSE;
      }
    }
    else {
      $page_match = TRUE;
    }
  }
  return $page_match;
}

/**
 * Helper function to check if user's DNT is set and hide tracking code.
 *
 * Based on headers sent by clients this function returns TRUE if BA code
 * should be added to the current page and otherwise FALSE.
 */
function _baidu_analytics_visibility_header($account) {
  $config = \Drupal::config('baidu_analytics.settings');
  if (($account->id() || \Drupal::config('system.performance')->get('cache.page.max_age') == 0) && $config->get('baidu_analytics_privacy_donottrack') && !empty($_SERVER['HTTP_DNT'])) {
    // Disable tracking if caching is disabled or a visitors is logged in and
    // have opted out from tracking via DNT (Do-Not-Track) header.
    return FALSE;
  }

  return TRUE;
}