Club Drupal

<?php

/**

 * @file

 * Pluggable system to provide advanced help facilities for Drupal and modules.

 *

 * Modules utilizing this help system should create a 'help' directory in their

 * module. Inside that directory place MODULENAME.help.ini which will be

 * formatted like this:

 *

 * @code

 * [buses]

 * title = "How buses are tied into the system"

 * file = buses

 *

 * [TOPIC_ID]

 * title = "Title of topic"

 * file = filename of topic, without the .html extension

 * weight = the importance of the topic on the index page

 * parent = the optional topic parent to use in the breadcrumb.

 * Can be either topic or module%topic

 * @endcode

 *

 * All topics are addressed by the module that provides the topic, and the topic

 * id. Links may be embedded as in the following example:

 *

 * @code

 * $output .= theme('advanced_help_topic', array('module' => $module, 'topic' => $topic));

 * @endcode

 *

 * Link to other topics using <a href="topic:module/topic">. (Using

 * this format ensures the popup status remains consistent for all

 * links.)

 */

/**

 * Implements hook_help().

 */

function advanced_help_help($path, $arg) {

  if ($path == 'admin/help#advanced_help') {

    $output = '<p>' . t('This module provides extended help and documentation.') . '</p>';

    if (function_exists('advanced_help_hint_docs')) {

      $output .= '<p>' . advanced_help_hint_docs('advanced_help', 'https://www.drupal.org/docs/7/modules/advanced-help', TRUE) . '</p>';

    }

    else {

      $output .= t('If you install and enable the module <strong>!url</strong>, you will get more help for <strong>Advanced help</strong>.',

        array('!url' => l('Advanced help hint', 'https://www.drupal.org/project/advanced_help_hint')));

    }

    return $output;

  }

}

/**

 * Implements hook_admin_paths_alter().

 *

 * Force help pages for this module to be rendered in admin theme.

 */

function advanced_help_admin_paths_alter(&$paths) {

  $paths['help/advanced_help/*'] = TRUE;

}

/**

 * Implements hook_menu().

 *

 * Strings in hook_menu() should not be run through t().

 */

function advanced_help_menu() {

  $help_exists = module_exists('help') ? TRUE : FALSE;

  if ($help_exists) {

    // Add tabs to core Help page to access Advanced Help.

    $items['admin/help/tab1'] = array(

      'title' => 'Help',

      'type' => MENU_DEFAULT_LOCAL_TASK,

      'weight' => 0,

    );

    $items['admin/help/ah'] = array(

      'title' => 'Advanced Help',

      'page callback' => 'advanced_help_index_page',

      'access arguments' => array('view advanced help index'),

      'type' => MENU_LOCAL_TASK,

      'weight' => 2,

    );

  }

  else {

    // Make Advanced Help the normal help.

    $items['admin/help/ah'] = array(

      'title' => 'Help',

      'page callback' => 'advanced_help_index_page',

      'access arguments' => array('view advanced help index'),

      'type' => MENU_NORMAL_ITEM,

      'weight' => 9,

    );

  }

  $items['help/ah/search/%'] = array(

    'title' => 'Search help',

    'page callback' => 'advanced_help_search_view',

    'page arguments' => array('advanced_help'),

    'access arguments' => array('view advanced help index'),

  );

  // View help topic.

  $items['help/%/%'] = array(

    'page callback' => 'advanced_help_topic_page',

    'page arguments' => array(1, 2),

    'access arguments' => array('view advanced help topic'),

    'type' => MENU_CALLBACK,

  );

  return $items;

}

/**

 * Implements hook_menu_alter().

 */

function advanced_help_menu_alter(&$callbacks) {

  // We need to fix the menu item provided by search module to restrict access.

  $callbacks['search/advanced_help/%menu_tail']['access callback'] = 'user_access';

  $callbacks['search/advanced_help/%menu_tail']['access arguments'] = array('view advanced help index');

}

/**

 * Implements hook_theme().

 */

function advanced_help_theme() {

  $hooks['advanced_help_topic'] = array(

    'variables' => array(

      'module' => NULL,

      'topic'  => NULL,

      'type'   => 'icon',

    ),

  );

  $hooks['advanced_help_popup'] = array(

    'render element' => 'content',

    'template' => 'advanced-help-popup',

  );

  return $hooks;

}

/**

 * Helper function to sort topics.

 */

function advanced_help_uasort($id_a, $id_b) {

  $topics = advanced_help_get_topics();

  list($module_a, $topic_a) = $id_a;

  $a = $topics[$module_a][$topic_a];

  list($module_b, $topic_b) = $id_b;

  $b = $topics[$module_b][$topic_b];

  $a_weight = isset($a['weight']) ? $a['weight'] : 0;

  $b_weight = isset($b['weight']) ? $b['weight'] : 0;

  if ($a_weight != $b_weight) {

    return ($a_weight < $b_weight) ? -1 : 1;

  }

  if ($a['title'] != $b['title']) {

    return ($a['title'] < $b['title']) ? -1 : 1;

  }

  return 0;

}

/**

 * Helper function for grabbing search keys. Function is missing in D7.

 *

 * http://api.drupal.org/api/function/search_get_keys/6

 */

function advanced_help_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'], 4);

    $keys = empty($_REQUEST['keys']) ? '' : $_REQUEST['keys'];

    $return = count($path) == 4 ? $path[3] : $keys;

  }

  return $return;

}

/**

 * Page callback for advanced help search.

 */

function advanced_help_search_view() {

  if (!module_exists('search')) {

    return drupal_not_found();

  }

  $breadcrumb[] = advanced_help_l(t('Advanced help'), 'admin/help/ah');

  if (!isset($_POST['form_id'])) {

    $keys = advanced_help_search_get_keys();

    // Only perform search if there is non-whitespace search term:

    $results = '';

    if (trim($keys)) {

      $search_results = search_data($keys, 'advanced_help');

      $search_results = drupal_render($search_results);

      // Collect the search results:

      $results = array(

        '#type' => 'markup',

        '#markup' => $search_results,

      );

    }

    // Construct the search form.

    $output['advanced_help_search_form'] = drupal_get_form('advanced_help_search_form', $keys);

    $output['results'] = $results;

  }

  else {

    $output = drupal_get_form('advanced_help_search_form', empty($keys) ? '' : $keys);

  }

  $popup = !empty($_GET['popup']) && user_access('view advanced help popup');

  if ($popup) {

    // Prevent devel module from spewing.

    $GLOBALS['devel_shutdown'] = FALSE;

    // Suppress admin_menu.

    module_invoke('admin_menu', 'suppress');

    drupal_set_breadcrumb(array_reverse($breadcrumb));

    print theme('advanced_help_popup', array('content' => $output));

    return;

  }

  $breadcrumb = array_merge(drupal_get_breadcrumb(), array_reverse($breadcrumb));

  drupal_set_breadcrumb($breadcrumb);

  return $output;

}

/**

 * Page callback to view the advanced help topic index.

 *

 * @param string $module

 *   Name of the module.

 *

 * @return array

 *   Returns module index.

 */

function advanced_help_index_page($module = '') {

  $topics = advanced_help_get_topics();

  $settings = advanced_help_get_settings();

  $output = array();

  // Print a search widget.

  $output['advanced_help_search'] = module_exists('search') ? drupal_get_form('advanced_help_search_form') : array('#markup' => t('Enable the search module to search help.'));

  $breadcrumb = array();

  if ($module) {

    if (empty($topics[$module])) {

      return drupal_not_found();

    }

    advanced_help_get_topic_hierarchy($topics);

    $items = advanced_help_get_tree($topics, $topics[$module]['']['children']);

    $breadcrumb[] = advanced_help_l(t('Advanced help'), 'admin/help/ah');

    drupal_set_title(t('@module help index', array('@module' => advanced_help_get_module_name($module))));

    $output['items-module'] = array(

      '#theme' => 'item_list',

      '#items' => $items,

    );

  }

  else {

    // Print a module index.

    $modules = array();

    $result = db_query('SELECT * FROM {system}');

    foreach ($result as $info) {

      $module_info = unserialize($info->info);

      $modules[$info->name] = isset($module_info['name']) ? $module_info['name'] : $info->name;

    }

    asort($modules);

    $items = array();

    foreach ($modules as $module => $module_name) {

      if (!empty($topics[$module]) && empty($settings[$module]['hide'])) {

        if (isset($settings[$module]['index name'])) {

          $name = $settings[$module]['index name'];

        }

        elseif (isset($settings[$module]['name'])) {

          $name = $settings[$module]['name'];

        }

        else {

          $name = t($module_name);

        }

        $items[] = advanced_help_l($name, "admin/help/ah/$module");

      }

    }

    drupal_set_title(t('Advanced help'));

    $output['items-nomodule'] = array(

      '#theme' => 'item_list',

      '#items' => $items,

    );

  }

  $popup = !empty($_GET['popup']) && user_access('view advanced help popup');

  if ($popup) {

    // Prevent devel module from spewing.

    $GLOBALS['devel_shutdown'] = FALSE;

    // Suppress admin_menu.

    module_invoke('admin_menu', 'suppress');

    drupal_set_breadcrumb(array_reverse($breadcrumb));

    print theme('advanced_help_popup', array('content' => $output));

    return;

  }

  $breadcrumb = array_merge(drupal_get_breadcrumb(), array_reverse($breadcrumb));

  drupal_set_breadcrumb($breadcrumb);

  return $output;

}

/**

 * Build a tree of advanced help topics.

 *

 * @param array $topics

 *   Topics.

 * @param array $topic_ids

 *   Topic Ids.

 * @param int $max_depth

 *   Maximum depth for subtopics.

 * @param int $depth

 *   Default depth for subtopics.

 *

 * @return array

 *   Returns list of topics/subtopics.

 */

function advanced_help_get_tree($topics, $topic_ids, $max_depth = -1, $depth = 0) {

  uasort($topic_ids, 'advanced_help_uasort');

  $items = array();

  foreach ($topic_ids as $info) {

    list($module, $topic) = $info;

    $item = advanced_help_l($topics[$module][$topic]['title'], "help/$module/$topic");

    if (!empty($topics[$module][$topic]['children']) && ($max_depth == -1 || $depth < $max_depth)) {

      $item .= theme('item_list', array(

        'items' => advanced_help_get_tree($topics, $topics[$module][$topic]['children'], $max_depth, $depth + 1),

      ));

    }

    $items[] = $item;

  }

  return $items;

}

/**

 * Build a hierarchy for a single module's topics.

 */

function advanced_help_get_topic_hierarchy(&$topics) {

  foreach ($topics as $module => $module_topics) {

    foreach ($module_topics as $topic => $info) {

      $parent_module = $module;

      // We have a blank topic that we don't want parented to itself.

      if (!$topic) {

        continue;

      }

      if (empty($info['parent'])) {

        $parent = '';

      }

      elseif (strpos($info['parent'], '%')) {

        list($parent_module, $parent) = explode('%', $info['parent']);

        if (empty($topics[$parent_module][$parent])) {

          // If it doesn't exist, top level.

          $parent = '';

        }

      }

      else {

        $parent = $info['parent'];

        if (empty($module_topics[$parent])) {

          // If it doesn't exist, top level.

          $parent = '';

        }

      }

      if (!isset($topics[$parent_module][$parent]['children'])) {

        $topics[$parent_module][$parent]['children'] = array();

      }

      $topics[$parent_module][$parent]['children'][] = array($module, $topic);

      $topics[$module][$topic]['_parent'] = array($parent_module, $parent);

    }

  }

}

/**

 * Implements hook_form_system_modules_alter().

 *

 * Add advanced help links to the modules page.

 */

function advanced_help_form_system_modules_alter(&$form, &$form_state) {

  if (!isset($form['modules'])) {

    return;

  }

  $advanced_help_modules = drupal_map_assoc(array_keys(advanced_help_get_topics()));

  foreach (element_children($form['modules']) as $group) {

    foreach (element_children($form['modules'][$group]) as $module) {

      if (isset($advanced_help_modules[$module])) {

        $form['modules'][$group][$module]['links']['help'] = array(

          '#type' => 'link',

          '#title' => t('Help'),

          '#href' => "admin/help/ah/$module",

          '#options' => array(

            'attributes' => array(

              'class' => array('module-link', 'module-link-help'),

              'title' => t('Help'),

            ),

          ),

        );

      }

    }

  }

}

/**

 * Form builder callback to build the search form.

 *

 * Load search/search.pages so that its template preprocess functions are

 * visible and can be invoked.

 */

function advanced_help_search_form($form, &$form_state, $keys = '') {

  module_load_include('inc', 'search', 'search.pages');

  $form = search_form($form, $form_state, 'admin/help/ah', $keys, 'advanced_help', t('Search help'));

  $form['basic']['inline']['submit']['#validate'] = array('search_form_validate');

  $form['basic']['inline']['submit']['#submit'] = array('advanced_help_search_form_submit');

  return $form;

}

/**

 * Process a search form submission.

 */

function advanced_help_search_form_submit($form, &$form_state) {

  $keys = empty($form_state['values']['processed_keys']) ? $form_state['values']['keys'] : $form_state['values']['processed_keys'];

  if ($keys == '') {

    form_set_error('keys', t('Please enter some keywords.'));

    return;

  }

  $popup = !empty($_GET['popup']) && user_access('view advanced help popup');

  if ($popup) {

    $form_state['redirect'] = array('help/ah/search/' . $keys, array('query' => array('popup' => 'true')));

  }

  else {

    $form_state['redirect'] = 'help/ah/search/' . $keys;

  }

}

/**

 * Small helper function to get a module's proper name.

 *

 * @param string $module

 *   Name of the module.

 *

 * @return string

 *   Returns module's descriptive name.

 */

function advanced_help_get_module_name($module) {

  $settings = advanced_help_get_settings();

  if (isset($settings[$module]['name'])) {

    $name = $settings[$module]['name'];

  }

  else {

    $info = db_query("SELECT s.info FROM {system} s WHERE s.name = :name",

      array(':name' => $module))

      ->fetchField();

    $info = unserialize($info);

    $name = t($info['name']);

  }

  return $name;

}

/**

 * Page callback to view a help topic.

 */

function advanced_help_topic_page($module, $topic) {

  if ('toc' == $topic) {

    return advanced_help_index_page($module);

  }

  $info = advanced_help_get_topic($module, $topic);

  if (!$info) {

    return drupal_not_found();

  }

  $popup = !empty($_GET['popup']) && user_access('view advanced help popup');

  drupal_set_title($info['title']);

  // Set up breadcrumb.

  $breadcrumb = array();

  $parent = $info;

  $pmodule = $module;

  // Loop checker.

  $checked = array();

  while (!empty($parent['parent'])) {

    if (strpos($parent['parent'], '%')) {

      list($pmodule, $ptopic) = explode('%', $parent['parent']);

    }

    else {

      $ptopic = $parent['parent'];

    }

    if (!empty($checked[$pmodule][$ptopic])) {

      break;

    }

    $checked[$pmodule][$ptopic] = TRUE;

    $parent = advanced_help_get_topic($pmodule, $ptopic);

    if (!$parent) {

      break;

    }

    $breadcrumb[] = advanced_help_l($parent['title'], "help/$pmodule/$ptopic");

  }

  $breadcrumb[] = advanced_help_l(advanced_help_get_module_name($pmodule), "admin/help/ah/$pmodule");

  $breadcrumb[] = advanced_help_l(t('Help'), "admin/help/ah");

  $output = advanced_help_view_topic($module, $topic, $popup);

  if (empty($output)) {

    $output = t('Missing help topic.');

  }

  if ($popup) {

    // Prevent devel module from spewing.

    $GLOBALS['devel_shutdown'] = FALSE;

    // Suppress admin_menu.

    module_invoke('admin_menu', 'suppress');

    drupal_set_breadcrumb(array_reverse($breadcrumb));

    print theme('advanced_help_popup', array('content' => $output));

    return;

  }

  drupal_add_css(drupal_get_path('module', 'advanced_help') . '/help.css');

  $breadcrumb[] = l(t('Home'), '');

  drupal_set_breadcrumb(array_reverse($breadcrumb));

  return $output;

}

/**

 * Implements hook_permission().

 */

function advanced_help_permission() {

  return array(

    'view advanced help topic' => array('title' => t('View help topics')),

    'view advanced help popup' => array('title' => t('View help popups')),

    'view advanced help index' => array('title' => t('View help index')),

  );

}

/**

 * Display a help icon with a link to view the topic in a popup.

 *

 * @param array $variables

 *   An associative array containing:

 *   - module: The module that owns this help topic.

 *   - topic: The identifier for the topic

 *   - type

 *     - 'icon' to display the question mark icon

 *     - 'title' to display the topic's title

 *     - any other text to display the text. Be sure to t() it!

 */

function theme_advanced_help_topic($variables) {

  $module = $variables['module'];

  $topic  = $variables['topic'];

  $type   = $variables['type'];

  if ('toc'  == $topic) {

    $info = array(

      'title' => 'Index page',

      'popup width' => 500,

      'popup height' => 500,

    );

  }

  else {

    $info = advanced_help_get_topic($module, $topic);

    if (!$info) {

      return;

    }

  }

  switch ($type) {

    case 'icon':

      $text = '<span>' . t('Help') . '</span>';

      $class = 'advanced-help-link';

      break;

    case 'title':

      $text = $info['title'];

      $class = 'advanced-help-title';

      break;

    default:

      $class = 'advanced-help-title';

      $text = $type;

      break;

  }

  if (user_access('view advanced help popup')) {

    drupal_add_css(drupal_get_path('module', 'advanced_help') . '/help-icon.css');

    return l($text, "help/$module/$topic", array(

      'attributes' => array(

        'class' => $class,

        'onclick' => "var w=window.open(this.href, 'advanced_help_window', 'width=" . $info['popup width'] . ",height=" . $info['popup height'] . ",scrollbars,resizable'); w.focus(); return false;",

        'title' => $info['title'],

      ),

      'query' => array('popup' => TRUE),

      'html' => TRUE)

    );

  }

  elseif (user_access('view advanced help topic')) {

    return l($text, "help/$module/$topic", array(

      'attributes' => array(

        'class' => $class,

        'title' => $info['title'],

      ),

      'html' => TRUE)

    );

  }

}

/**

 * Load and render a help topic.

 */

function advanced_help_get_topic_filename($module, $topic) {

  $info = advanced_help_get_topic_file_info($module, $topic);

  if ($info) {

    return "$info[path]/$info[file]";

  }

}

/**

 * Get the module type (theme or module).

 */

function _advanced_help_get_module_type($module) {

  $theme_list = array_keys(list_themes());

  $is_theme = in_array($module, $theme_list);

  return $is_theme ? 'theme' : 'module';

}

/**

 * Load and render a help topic.

 *

 * The strategy is first to see if a translated file for the current

 * active language exists.  If not found, look for the default.

 */

function advanced_help_get_topic_file_info($module, $topic) {

  global $language;

  $info = advanced_help_get_topic($module, $topic);

  if (empty($info)) {

    return;

  }

  // Search paths:

  $module_type = _advanced_help_get_module_type($module);

  $paths = array(

    // First see if a translation exists.

    drupal_get_path($module_type, $module) . "/translations/help/$language->language",

    // In same directory as .inc file.

    $info['path'],

  );

  foreach ($paths as $path) {

    if (file_exists("$path/$info[file]")) {

      return array('path' => $path, 'file' => $info['file']);

    }

  }

}

/**

 * Load and render a help topic.

 *

 * @param string $module

 *   Name of the module.

 * @param string $topic

 *   Name of the topic.

 * @param bool $popup

 *   Whether to show in popup or not.

 *

 * @return string

 *   Returns formatted topic.

 */

function advanced_help_view_topic($module, $topic, $popup = FALSE) {

  $file_info = advanced_help_get_topic_file_info($module, $topic);

  if ($file_info) {

    $info = advanced_help_get_topic($module, $topic);

    $file = "./$file_info[path]/$file_info[file]";

    // Fix invalid byte sequences (https://www.drupal.org/node/2659746).

    $output = file_get_contents($file);

    mb_substitute_character(0xfffd);

    $output = mb_convert_encoding($output, 'UTF-8', 'UTF-8');

    if (isset($info['readme file']) && $info['readme file']) {

      $ext = pathinfo($file, PATHINFO_EXTENSION);

      if ('md' == $ext && module_exists('markdown')) {

        $filters = module_invoke('markdown', 'filter_info');

        $md_info = $filters['filter_markdown'];

        if (function_exists($md_info['process callback'])) {

          $function = $md_info['process callback'];

          $output = '<div class="advanced-help-topic">' . filter_xss_admin($function($output, NULL)) . '</div>';

        }

        else {

          $output = '<div class="advanced-help-topic"><pre class="readme">' . check_plain($output) . '</pre></div>';

        }

      }

      else {

        $readme = '';

        if ('md' == $ext) {

          $readme .=

            '<p>' .

            t('If you install the !module module, the text below will be filtered by the module, producing rich text.',

              array(

                '!module' => l(t('Markdown filter'),

                  'https://www.drupal.org/project/markdown',

                  array('attributes' => array('title' => t('Link to project.'))))

              )) . '</p>';

        }

        $readme .=

          '<div class="advanced-help-topic"><pre class="readme">' . check_plain($output) . '</pre></div>';

        $output = $readme;

      }

      return $output;

    }

    // Make some exchanges. The strtr is because url() translates $ into %24

    // but we need to change it back for the regex replacement.

    //

    // Change 'topic:' to the URL for another help topic.

    if ($popup) {

      $output = preg_replace('/href="topic:([^"]+)"/', 'href="' . strtr(url('help/$1', array('query' => array('popup' => 'true'))), array('%24' => '$')) . '"', $output);

      $output = preg_replace('/src="topic:([^"]+)"/', 'src="' . strtr(url('help/$1', array('query' => array('popup' => 'true'))), array('%24' => '$')) . '"', $output);

      $output = preg_replace('/&topic:([^"]+)&/', strtr(url('help/$1', array('query' => array('popup' => 'true'))), array('%24' => '$')), $output);

    }

    else {

      $output = preg_replace('/href="topic:([^"]+)"/', 'href="' . strtr(url('help/$1'), array('%24' => '$')) . '"', $output);

      $output = preg_replace('/src="topic:([^"]+)"/', 'src="' . strtr(url('help/$1'), array('%24' => '$')) . '"', $output);

      $output = preg_replace('/&topic:([^"]+)&/', strtr(url('help/$1'), array('%24' => '$')), $output);

    }

    global $base_path;

    // Change 'path:' to the URL to the base help directory.

    $output = preg_replace('/href="path:([^"]+)"/', 'href="' . $base_path . $info['path'] . '/$1"', $output);

    $output = preg_replace('/src="path:([^"]+)"/', 'src="' . $base_path . $info['path'] . '/$1"', $output);

    $output = str_replace('&path&', $base_path . $info['path'] . '/', $output);

    // Change 'trans_path:' to the URL to the actual help directory.

    $output = preg_replace('/href="trans_path:([^"]+)"/', 'href="' . $base_path . $file_info['path'] . '/$1"', $output);

    $output = preg_replace('/src="trans_path:([^"]+)"/', 'src="' . $base_path . $file_info['path'] . '/$1"', $output);

    $output = str_replace('&trans_path&', $base_path . $file_info['path'] . '/', $output);

    // Change 'base_url:' to the URL to the site.

    $output = preg_replace('/href="base_url:([^"]+)"/', 'href="' . strtr(url('$1'), array('%24' => '$')) . '"', $output);

    $output = preg_replace('/src="base_url:([^"]+)"/', 'src="' . strtr(url('$1'), array('%24' => '$')) . '"', $output);

    $output = preg_replace('/&base_url&([^"]+)"/', strtr(url('$1'), array('%24' => '$')) . '"', $output);

    // Run the line break filter if requested.

    if (!empty($info['line break'])) {

      // Remove the header since it adds an extra <br /> to the filter.

      $output = preg_replace('/^<!--[^\n]*-->\n/', '', $output);

      $output = _filter_autop($output);

    }

    if (!empty($info['ini']['format'])) {

      $filter = $info['ini']['format'];

      if (filter_format_exists($filter)) {

        $output = check_markup($output, $filter);

      }

      else {

        drupal_set_message(t('Ini-file request non-existing format: “!format”.', array('!format' => $filter)), 'error');

      }

    }

    if (!empty($info['navigation'])) {

      $topics = advanced_help_get_topics();

      advanced_help_get_topic_hierarchy($topics);

      if (!empty($topics[$module][$topic]['children'])) {

        $items = advanced_help_get_tree($topics, $topics[$module][$topic]['children']);

        $output .= theme('item_list', array('items' => $items));

      }

      list($parent_module, $parent_topic) = $topics[$module][$topic]['_parent'];

      if ($parent_topic) {

        $parent = $topics[$module][$topic]['_parent'];

        $up = "help/$parent[0]/$parent[1]";

      }

      else {

        $up = "admin/help/ah/$module";

      }

      $siblings = $topics[$parent_module][$parent_topic]['children'];

      uasort($siblings, 'advanced_help_uasort');

      $prev = $next = NULL;

      $found = FALSE;

      foreach ($siblings as $sibling) {

        list($sibling_module, $sibling_topic) = $sibling;

        if ($found) {

          $next = $sibling;

          break;

        }

        if ($sibling_module == $module && $sibling_topic == $topic) {

          $found = TRUE;

          continue;

        }

        $prev = $sibling;

      }

      if ($prev || $up || $next) {

        $navigation = '<div class="help-navigation clear-block">';

        if ($prev) {

          $navigation .= advanced_help_l('«« ' . $topics[$prev[0]][$prev[1]]['title'], "help/$prev[0]/$prev[1]", array('attributes' => array('class' => 'help-left')));

        }

        if ($up) {

          $navigation .= advanced_help_l(t('Up'), $up, array('attributes' => array('class' => $prev ? 'help-up' : 'help-up-noleft')));

        }

        if ($next) {

          $navigation .= advanced_help_l($topics[$next[0]][$next[1]]['title'] . ' »»', "help/$next[0]/$next[1]", array('attributes' => array('class' => 'help-right')));

        }

        $navigation .= '</div>';

        $output .= $navigation;

      }

    }

    if (!empty($info['css'])) {

      drupal_add_css($info['path'] . '/' . $info['css']);

    }

    $output = '<div class="advanced-help-topic">' . $output . '</div>';

    drupal_alter('advanced_help_topic', $output, $popup);

    return $output;

  }

}

/**

 * Get the information for a single help topic.

 */

function advanced_help_get_topic($module, $topic) {

  $topics = advanced_help_get_topics();

  if (!empty($topics[$module][$topic])) {

    return $topics[$module][$topic];

  }

}

/**

 * Search the system for all available help topics.

 */

function advanced_help_get_topics() {

  $ini = _advanced_help_parse_ini();

  return $ini['topics'];

}

/**

 * Returns advanced help settings.

 */

function advanced_help_get_settings() {

  $ini = _advanced_help_parse_ini();

  return $ini['settings'];

}

/**

 * Function to parse ini / txt files.

 */

function _advanced_help_parse_ini() {

  global $language;

  static $ini = NULL;

  if (!isset($ini)) {

    $cache = cache_get('advanced_help_ini:' . $language->language);

    if ($cache) {

      $ini = $cache->data;

    }

  }

  if (!isset($ini)) {

    // No cached list of topics - create it.

    $ini = array('topics' => array(), 'settings' => array());

    foreach (array_merge(module_list(), list_themes()) as $plugin) {

      $module = is_string($plugin) ? $plugin : $plugin->name;

      $module_path = drupal_get_path(is_string($plugin) ? 'module' : 'theme', $module);

      // Parse ini-file if it exists

      if (file_exists("$module_path/help/$module.help.ini")) {

        $path_html = "$module_path/help";

        $info = parse_ini_file("./$module_path/help/$module.help.ini", TRUE);

        if (!$info) {

          drupal_set_message(t('There is a syntax error in the default .ini-file.  Unable to display topics.'), 'error');

        }

      }

      else {

        $info = array();

      }

      if (empty($info) || !empty($info['advanced help settings']['show readme'])) {

        // Look for one or more README files.

        $files = file_scan_directory("./$module_path",

          '/^(readme).*\.(txt|md)$/i', array('recurse' => FALSE));

        $path_readme = "$module_path";

        foreach ($files as $name => $fileinfo) {

          $info[$fileinfo->filename] = array(

            'line break' => TRUE,

            'readme file' => TRUE,

            'file' => $fileinfo->filename,

            'title' => $fileinfo->name,

            'weight' => -99,

          );

        }

      }

      if (!empty($info)) {

        // Get translated titles:

        $translation = array();

        if (file_exists("$module_path/translations/help/$language->language/$module.help.ini")) {

          $translation = parse_ini_file("$module_path/translations/help/$language->language/$module.help.ini", TRUE);

          if (!$translation) {

            drupal_set_message(t('There is a syntax error in the translated .ini-file.'), 'error');

          }

        }

        $ini['settings'][$module] = array();

        if (!empty($info['advanced help settings'])) {

          $ini['settings'][$module] = $info['advanced help settings'];

          unset($info['advanced help settings']);

          // Check translated strings for translatable global settings.

          if (isset($translation['advanced help settings']['name'])) {

            $ini['settings']['name'] = $translation['advanced help settings']['name'];

          }

          if (isset($translation['advanced help settings']['index name'])) {

            $ini['settings']['index name'] = $translation['advanced help settings']['index name'];

          }

        }

        foreach ($info as $name => $topic) {

          // Each topic should have a name, a title, a file and path.

          $file = !empty($topic['file']) ? $topic['file'] : $name;

          $ini['topics'][$module][$name] = array(

            'name' => $name,

            'module' => $module,

            'ini' => $topic,

            'title' => !empty($translation[$name]['title']) ? $translation[$name]['title'] : $topic['title'],

            'weight' => isset($topic['weight']) ? $topic['weight'] : 0,

            'parent' => isset($topic['parent']) ? $topic['parent'] : 0,

            'popup width' => isset($topic['popup width']) ? $topic['popup width'] : 500,

            'popup height' => isset($topic['popup height']) ? $topic['popup height'] : 500,

            // Require extension.

            'file' => isset($topic['readme file']) ? $file : $file . '.html',

            // Not in .ini file.

            'path' => isset($topic['readme file']) ? $path_readme : $path_html,

            'line break' => isset($topic['line break']) ? $topic['line break'] : (isset($ini['settings'][$module]['line break']) ? $ini['settings'][$module]['line break'] : FALSE),

            'navigation' => isset($topic['navigation']) ? $topic['navigation'] : (isset($ini['settings'][$module]['navigation']) ? $ini['settings'][$module]['navigation'] : TRUE),

            'show readme' => isset($topic['show readme']) ? $topic['show readme'] : (isset($ini['settings'][$module]['show readme']) ? $ini['settings'][$module]['show readme'] : FALSE),

            'css' => isset($topic['css']) ? $topic['css'] : (isset($ini['settings'][$module]['css']) ? $ini['settings'][$module]['css'] : NULL),

            'readme file' => isset($topic['readme file']) ? $topic['readme file'] : FALSE,

          );

        }

      }

    }

    drupal_alter('advanced_help_topic_info', $ini);

    cache_set('advanced_help_ini:' . $language->language, $ini);

  }

  return $ini;

}

/**

 * Implements hook_search_info().

 *

 * Returns title for the tab on search page & path component after 'search/'.

 */

function advanced_help_search_info() {

  return array(

    'title' => t('Help'),

    'path' => 'advanced_help',

  );

}

/**

 * Implements hook_search_execute().

 */

function advanced_help_search_execute($keys = NULL) {

  $topics = advanced_help_get_topics();

  $query = db_select('search_index', 'i', array('target' => 'slave'))

    ->extend('SearchQuery')

    ->extend('PagerDefault');

  $query->join('advanced_help_index', 'ahi', 'i.sid = ahi.sid');

  $query->searchExpression($keys, 'help');

  // Only continue if the first pass query matches.

  if (!$query->executeFirstPass()) {

    return array();

  }

  $results = array();

  $find = $query->execute();

  foreach ($find as $item) {

    $sids[] = $item->sid;

  }

  $query = db_select('advanced_help_index', 'ahi');

  $result = $query

    ->fields('ahi')

    ->condition('sid', $sids, 'IN')

    ->execute();

  foreach ($result as $sid) {

    // Guard against removed help topics that are still indexed.

    if (empty($topics[$sid->module][$sid->topic])) {

      continue;

    }

    $info = $topics[$sid->module][$sid->topic];

    $text = advanced_help_view_topic($sid->module, $sid->topic);

    $results[] = array(

      'link' => advanced_help_url("help/$sid->module/$sid->topic"),

      'title' => $info['title'],

      'snippet' => search_excerpt($keys, $text),

    );

  }

  return $results;

}

/**

 * Implements hook_search_reset().

 */

function advanced_help_search_reset() {

  variable_del('advanced_help_last_cron');

}

/**

 * Implements hook_search_status().

 */

function advanced_help_search_status() {

  $topics = advanced_help_get_topics();

  $total = 0;

  foreach ($topics as $module => $module_topics) {

    foreach ($module_topics as $topic => $info) {

      $file = advanced_help_get_topic_filename($module, $topic);

      if ($file) {

        $total++;

      }

    }

  }

  $last_cron = variable_get('advanced_help_last_cron', array('time' => 0));

  $indexed = 0;

  if ($last_cron['time'] != 0) {

    $indexed = db_query("SELECT COUNT(*) FROM {search_dataset} sd WHERE sd.type = 'help' AND sd.sid IS NOT NULL AND sd.reindex = 0")->fetchField();

  }

  return array('remaining' => $total - $indexed, 'total' => $total);

}

/**

 * Gets search id for each topic.

 *

 * Get or create an sid (search id) that correlates to each topic for

 * the search system.

 */

function advanced_help_get_sids(&$topics) {

  global $language;

  $result = db_query("SELECT * FROM {advanced_help_index} WHERE language = :language",

    array(':language' => $language->language));

  foreach ($result as $sid) {

    if (empty($topics[$sid->module][$sid->topic])) {

      db_query("DELETE FROM {advanced_help_index} WHERE sid = :sid",

        array(':sid' => $sid->sid));

    }

    else {

      $topics[$sid->module][$sid->topic]['sid'] = $sid->sid;

    }

  }

}

/**

 * Implements hook_update_index().

 */

function advanced_help_update_index() {

  global $language;

  // If we got interrupted by limit, this will contain the last module

  // and topic we looked at.

  $last = variable_get('advanced_help_last_cron', array('time' => 0));

  $limit = intval(variable_get('search_cron_limit', 100));

  $topics = advanced_help_get_topics();

  advanced_help_get_sids($topics);

  $count = 0;

  foreach ($topics as $module => $module_topics) {

    // Fast forward if necessary.

    if (!empty($last['module']) && $last['module'] != $module) {

      continue;

    }

    foreach ($module_topics as $topic => $info) {

      // Fast forward if necessary.

      if (!empty($last['topic']) && $last['topic'] != $topic) {

        continue;

      }

      // If we've been looking to catch up, and we have, reset so we

      // stop fast forwarding.

      if (!empty($last['module'])) {

        unset($last['topic']);

        unset($last['module']);

      }

      $file = advanced_help_get_topic_filename($module, $topic);

      if ($file && (empty($info['sid']) || filemtime($file) > $last['time'])) {

        if (empty($info['sid'])) {

          $info['sid'] = db_insert('advanced_help_index')

            ->fields(array(

              'module' => $module,

              'topic'  => $topic,

              'language' => $language->language,

            ))

            ->execute();

        }

        search_index($info['sid'], 'help', '<h1>' . $info['title'] . '</h1>' . file_get_contents($file));

        $count++;

        if ($count >= $limit) {

          $last['topic'] = $topic;

          $last['module'] = $module;

          // Don't change time if we stop.

          variable_set('advanced_help_last_cron', $last);

          return;

        }

      }

    }

  }

  variable_set('advanced_help_last_cron', array('time' => time()));

}

/**

 * Fill in a bunch of page variables for our specialized popup page.

 */

function template_preprocess_advanced_help_popup(&$variables) {

  // Add favicon.

  if (theme_get_setting('toggle_favicon')) {

    drupal_add_html_head('<link rel="shortcut icon" href="' . check_url(theme_get_setting('favicon')) . '" type="image/x-icon" />');

  }

  global $theme;

  // Construct page title.

  if (drupal_get_title()) {

    $head_title = array(

      strip_tags(drupal_get_title()),

      variable_get('site_name', 'Drupal'),

    );

  }

  else {

    $head_title = array(variable_get('site_name', 'Drupal'));

    if (variable_get('site_slogan', '')) {

      $head_title[] = variable_get('site_slogan', '');

    }

  }

  drupal_add_css(drupal_get_path('module', 'advanced_help') . '/help-popup.css');

  drupal_add_css(drupal_get_path('module', 'advanced_help') . '/help.css');

  $variables['head_title']        = implode(' | ', $head_title);

  $variables['base_path']         = base_path();

  $variables['front_page']        = url();

  $variables['breadcrumb']        = theme('breadcrumb', array('breadcrumb' => drupal_get_breadcrumb()));

  $variables['feed_icons']        = drupal_get_feeds();

  $variables['head']              = drupal_get_html_head();

  $variables['language']          = $GLOBALS['language'];

  $variables['language']->dir     = $GLOBALS['language']->direction ? 'rtl' : 'ltr';

  $variables['logo']              = theme_get_setting('logo');

  $variables['messages']          = theme('status_messages');

  $variables['site_name']         = (theme_get_setting('toggle_name') ? variable_get('site_name', 'Drupal') : '');

  $variables['css']               = drupal_add_css();

  $css = drupal_add_css();

  // Remove theme css.

  foreach ($css as $key => $value) {

    if ($value['group'] == CSS_THEME) {

      $exclude[$key] = FALSE;

    }

  }

  $css = array_diff_key($css, $exclude);

  $variables['styles']            = drupal_get_css($css);

  $variables['scripts']           = drupal_get_js();

  $variables['title']             = drupal_get_title();

  // This function can be called either with a render array or

  // an already rendered string.

  if (is_array($variables['content'])) {

    $variables['content'] = drupal_render($variables['content']);

  }

  // Closure should be filled last.

  // There has never been a theme hook for closure (going back to

  // first release 2008-04-17), so it is always 0 bytes.

  // Unable to figure out its purpose - commenting out.

  // $variables['closure'] = theme('closure');

}

/**

 * Format a link but preserve popup identity.

 */

function advanced_help_l($text, $dest, $options = array()) {

  $popup = !empty($_GET['popup']) && user_access('view advanced help popup');

  if ($popup) {

    if (empty($options['query'])) {

      $options['query'] = array();

    }

    if (is_array($options['query'])) {

      $options['query'] += array('popup' => TRUE);

    }

    else {

      $options['query'] += '&popup=TRUE';

    }

  }

  return l($text, $dest, $options);

}

/**

 * Format a URL but preserve popup identity.

 */

function advanced_help_url($dest, $options = array()) {

  $popup = !empty($_GET['popup']) && user_access('view advanced help popup');

  if ($popup) {

    if (empty($options['query'])) {

      $options['query'] = array();

    }

    $options['query'] += array('popup' => TRUE);

  }

  return url($dest, $options);

}