<?php

/**
 * @file
 * Administration toolbar for quick access to top level administration items.
 */

use Symfony\Component\HttpFoundation\JsonResponse;
use Drupal\Core\Template\Attribute;

/**
 * Implements hook_help().
 */
function toolbar_help($path, $arg) {
  switch ($path) {
    case 'admin/help#toolbar':
      $output = '<h3>' . t('About') . '</h3>';
      $output .= '<p>' . t('The Toolbar module displays links to top-level administration menu items and links from other modules at the top of the screen. For more information, see the online handbook entry for <a href="@toolbar">Toolbar module</a>.', array('@toolbar' => 'http://drupal.org/documentation/modules/toolbar')) . '</p>';
      $output .= '<h3>' . t('Uses') . '</h3>';
      $output .= '<dl>';
      $output .= '<dt>' . t('Displaying administrative links') . '</dt>';
      $output .= '<dd>' . t('The Toolbar module displays a bar containing top-level administrative links across the top of the screen. Below that, the Toolbar module has a <em>drawer</em> section where it displays links provided by other modules, such as the core <a href="@shortcuts-help">Shortcut module</a>. The drawer can be hidden/shown by clicking on its corresponding tab.', array('@shortcuts-help' => url('admin/help/shortcut'))) . '</dd>';
      $output .= '</dl>';
      return $output;
  }
}

/**
 * Implements hook_permission().
 */
function toolbar_permission() {
  return array(
    'access toolbar' => array(
      'title' => t('Use the administration toolbar'),
    ),
  );
}

/**
 * Implements hook_theme().
 */
function toolbar_theme($existing, $type, $theme, $path) {
  $items['toolbar'] = array(
    'render element' => 'toolbar',
    'template' => 'toolbar',
  );
  return $items;
}

/**
 * Implements hook_menu().
 */
function toolbar_menu() {
  $items['toolbar/subtrees/%'] = array(
    'page callback' => 'toolbar_subtrees_jsonp',
    'page arguments' => array(2),
    'access callback' => '_toolbar_subtrees_access',
    'access arguments' => array(2),
    'type' => MENU_CALLBACK,
  );
  return $items;
}

/**
 * Access callback: Returns if the user has access to the rendered subtree requested by the hash.
 *
 * @see toolbar_menu().
 */
function _toolbar_subtrees_access($hash) {
  return user_access('access toolbar') && ($hash == _toolbar_get_subtree_hash());
}

/**
 * Page callback: Returns the rendered subtree of each top-level toolbar link.
 *
 * @see toolbar_menu().
 */
function toolbar_subtrees_jsonp($hash) {
  _toolbar_initialize_page_cache();
  $subtrees = toolbar_get_rendered_subtrees();
  $response = new JsonResponse($subtrees);
  $response->setCallback('Drupal.toolbar.setSubtrees');
  return $response;
}

/**
 * Use Drupal's page cache for toolbar/subtrees/*, even for authenticated users.
 *
 * This gets invoked after full bootstrap, so must duplicate some of what's
 * done by _drupal_bootstrap_page_cache().
 *
 * @todo Replace this hack with something better integrated with DrupalKernel
 *   once Drupal's page caching itself is properly integrated.
 */
function _toolbar_initialize_page_cache() {
  $GLOBALS['conf']['system.performance']['cache']['page']['enabled'] = TRUE;
  drupal_page_is_cacheable(TRUE);

  // If we have a cache, serve it.
  // @see _drupal_bootstrap_page_cache()
  $cache = drupal_page_get_cache();
  if (is_object($cache)) {
    header('X-Drupal-Cache: HIT');
    // Restore the metadata cached with the page.
    $_GET['q'] = $cache->data['path'];
    date_default_timezone_set(drupal_get_user_timezone());

    drupal_serve_page_from_cache($cache);

    // We are done.
    exit;
  }

  // Otherwise, create a new page response (that will be cached).
  header('X-Drupal-Cache: MISS');

  // The Expires HTTP header is the heart of the client-side HTTP caching. The
  // additional server-side page cache only takes effect when the client
  // accesses the callback URL again (e.g., after clearing the browser cache or
  // when force-reloading a Drupal page).
  $max_age = 3600 * 24 * 365;
  drupal_add_http_header('Expires', gmdate(DATE_RFC1123, REQUEST_TIME + $max_age));
  drupal_add_http_header('Cache-Control', 'private, max-age=' . $max_age);
}

/**
 * Implements hook_page_build().
 *
 * Add admin toolbar to the page_top region automatically.
 */
function toolbar_page_build(&$page) {
  $page['page_top']['toolbar'] = array(
    '#pre_render' => array('toolbar_pre_render'),
    '#access' => user_access('access toolbar'),
  );
}

/**
 * Provides pre_render function for the toolbar.
 *
 * Since building the toolbar takes some time, it is done just prior to
 * rendering to ensure that it is built only if it will be displayed.
 *
 * @see toolbar_page_build().
 */
function toolbar_pre_render($toolbar) {
  $toolbar = array_merge($toolbar, toolbar_view());
  return $toolbar;
}

/**
 * Implements template_preprocess_HOOK().
 */
function template_preprocess_toolbar(&$variables) {
  // Metadata for the toolbar wrapping element.
  $variables['attributes'] = new Attribute(array(
    // The id cannot be simply "toolbar" or it will clash with the simpletest
    // tests listing which produces a checkbox with attribute id="toolbar"
    'id' => 'toolbar-administration',
    // The 'overlay-displace-top' class pushes the overlay down, so it appears
    // below the toolbar.
    'class' => array('toolbar', 'overlay-displace-top'),
    'role' => 'navigation'
  ));

  // Provide a convenience variable for the themed tabs.
  $variables['toolbar']['tabs']['#attributes']['class'][] = 'overlay-displace-top';
  $variables['tabs'] = $variables['toolbar']['tabs'];

  // Place the tabs in a top-level variable so that attribute information
  // can be associated with each one.
  foreach ($variables['toolbar']['trays'] as $key => $tray) {
    // Create tray heading text. Prefer the provided heading text if it exists.
    $heading = isset($tray['#heading']) ? $tray['#heading'] : t('@group actions', array('@group' => $key));

    $variables['trays'][$key] = array(
      'heading' => $heading,
      'content' => $variables['toolbar']['trays'][$key],
      'attributes' => new Attribute(array(
          'id' => 'toolbar-tray-' . $key,
          'class' => array('tray', 'overlay-displace-top', $key),
          'data-toolbar-tray' => $key,
          'aria-owned-by' => 'toolbar-tab-' . $key,
        )
      ),
    );
  }
}

/**
 * Implements hook_system_info_alter().
 *
 * Indicate that the 'page_top' region (in which the toolbar will be displayed)
 * is an overlay supplemental region that should be refreshed whenever its
 * content is updated.
 *
 * This information is provided for any module that might need to use it, not
 * just the core Overlay module.
 */
function toolbar_system_info_alter(&$info, $file, $type) {
  if ($type == 'theme') {
    $info['overlay_supplemental_regions'][] = 'page_top';
  }
}

/**
 * Implements hook_toolbar().
 */
function toolbar_toolbar() {
  $items = array();

  // The 'Home' tab is a simple link, with no corresponding tray.
  $items['home'] = array(
    'tab' => array(
      'title' => t('Home'),
      'href' => '<front>',
      'html' => FALSE,
      'attributes' => array(
        'title' => t('Home page'),
        'class' => array('icon', 'icon-home'),
      ),
    ),
    'weight' => -20,
  );

  // Retrieve the administration menu from the database.
  $tree = toolbar_get_menu_tree();

  // Add attributes to the links before rendering.
  toolbar_menu_navigation_links($tree);

  $menu = array(
    'toolbar_administration' => array(
      '#type' => 'container',
      '#attributes' => array(
        'class' => array('toolbar-menu',),
      ),
      'administration_menu' => menu_tree_output($tree),
    ),
    '#heading' => t('Administration menu'),
  );

  // To conserve bandwidth, we only include the top-level links in the HTML.
  // The subtrees are included in a JSONP script, cached by the browser. Here we
  // add that JSONP script. We add it as an external script, because it's a
  // Drupal path, not a file available via a stream wrapper.
  // @see toolbar_subtrees_jsonp()
  $menu['toolbar_administration']['#attached']['js'][url('toolbar/subtrees/' . _toolbar_get_subtree_hash())] = array('type' => 'external');

  $items['administration'] = array(
    'tab' => array(
      'title' => t('Menu'),
      'href' => 'admin',
      'html' => FALSE,
      'attributes' => array(
        'title' => t('Admin menu'),
        'class' => array('icon', 'icon-menu'),
      ),
    ),
    'tray' => $menu,
    'weight' => -15,
  );

  return $items;
}

/**
 * Builds the Toolbar as a structured array ready for drupal_render().
 *
 * @return
 *   A renderable arrray, with two children:
 *   - 'tabs': an array of links, rendered by theme('links').
 *   - 'trays': an array of render elements displayed when the corresponding tab
 *     is activated.
 */
function toolbar_view() {

  $build = array('#theme' => 'toolbar');
  $build['#attached']['library'][] = array('toolbar', 'toolbar');

  // Get the configured breakpoint to switch from vertical to horizontal
  // toolbar presentation.
  $breakpoints = entity_load('breakpoint_group', 'module.toolbar.toolbar');
  if (!empty($breakpoints)) {
    $media_queries = array();
    $media_queries['toolbar']['breakpoints'] = array_map(
      function($object) {return $object->mediaQuery;},
      $breakpoints->breakpoints);

    $build['#attached']['js'][] = array(
      'data' => $media_queries,
      'type' => 'setting',
    );
    // // Load the breakpoints for toolbar.
    foreach ($breakpoints->breakpoints as $key => $breakpoint) {
      $build['#attached']['js'][0]['data']['toolbar']['breakpoints'][$key] = $breakpoint->mediaQuery;
    }
  }

  // Get toolbar items from all modules that implement hook_toolbar() or
  // hook_toolbar_alter().
  $toolbar_groups = module_invoke_all('toolbar');
  drupal_alter('toolbar', $toolbar_groups);
  uasort($toolbar_groups, 'drupal_sort_weight');

  // Build the tabs and trays from the toolbar groups.
  $build['trays'] = array();
  $build['tabs'] = array(
    '#theme' => 'links',
    '#links' => array(),
    '#attributes' => array(
      'class' => array('bar', 'clearfix'),
    ),
    '#heading' => array('text' => t('Toolbar'), 'level' => 'h2', 'class' => 'element-invisible'),
  );
  $tab_defaults = array(
    'title' => '',
    'href' => '',
    'html' => FALSE,
    'attributes' => new Attribute(),
  );

  foreach ($toolbar_groups as $group => $items) {
    if ($tab = $items['tab']) {
      // Merge in the defaults.
      $tab += $tab_defaults;
    }
    // Register a tray if one is associated with this tab.
    if (!empty($items['tray'])) {
      // Provide an id, a data attribute linking each tab to the corresponding
      // tray and aria information.
      $tab['attributes']['id'] = 'toolbar-tab-' . $group;
      $tab['attributes']['data-toolbar-tray'] = $group;
      $tab['attributes']['aria-owns'] = 'toolbar-tray-' . $group;
      $tab['attributes']['role'] = 'button';
      $tab['attributes']['aria-pressed'] = 'false';

      if (array_key_exists($group, $build['trays'])) {
        array_merge($build['trays'][$group], $items['tray']);
      }
      else {
        // Assign the tray to the build.
        $build['trays'][$group] = $items['tray'];
      }
    }
    // Assign the tabs to the build.
    $build['tabs']['#links'][$group] = $tab;
  }

  return $build;
}

/**
 * Gets only the top level items below the 'admin' path.
 *
 * @return
 *   An array containing a menu tree of top level items below the 'admin' path.
 */
function toolbar_get_menu_tree() {
  $tree = array();
  $admin_link = db_query('SELECT * FROM {menu_links} WHERE menu_name = :menu_name AND module = :module AND link_path = :path', array(':menu_name' => 'admin', ':module' => 'system', ':path' => 'admin'))->fetchAssoc();
  if ($admin_link) {
    $tree = menu_build_tree('admin', array(
      'expanded' => array($admin_link['mlid']),
      'min_depth' => $admin_link['depth'] + 1,
      'max_depth' => $admin_link['depth'] + 1,
    ));
  }

  return $tree;
}

/**
 * Generates an array of links from a menu tree array.
 *
 * Based on menu_navigation_links(). Adds path based IDs and icon placeholders
 * to the links.
 *
 * @return
 *   An array of links as defined above.
 */
function toolbar_menu_navigation_links(&$tree) {
  foreach ($tree as $key => $item) {
    // Configure sub-items.
    if (!empty($item['below'])) {
      toolbar_menu_navigation_links($tree[$key]['below']);
    }
    // Make sure we have a path specific ID in place, so we can attach icons
    // and behaviors to the items.
    $tree[$key]['link']['localized_options']['attributes'] = array(
      'id' => 'toolbar-link-' . str_replace(array('/', '<', '>'), array('-', '', ''), $item['link']['link_path']),
      'class' => array(
        'icon',
        'icon-' . strtolower(str_replace(' ', '-', $item['link']['title'])),
      ),
    );
  }
}

/**
 * Returns the rendered subtree of each top-level toolbar link.
 */
function toolbar_get_rendered_subtrees() {
  $subtrees = array();
  $tree = toolbar_get_menu_tree();
  foreach ($tree as $tree_item) {
    $item = $tree_item['link'];
    if (!$item['hidden'] && $item['access']) {
      if ($item['has_children']) {
        $query = db_select('menu_links');
        $query->addField('menu_links', 'mlid');
        $query->condition('has_children', 1);
        for ($i=1; $i <= $item['depth']; $i++) {
          $query->condition('p' . $i, $item['p' . $i]);
        }
        $parents = $query->execute()->fetchCol();
        $subtree = menu_build_tree($item['menu_name'], array('expanded' => $parents, 'min_depth' => $item['depth']+1));
        toolbar_menu_navigation_links($subtree);
        $subtree = menu_tree_output($subtree);
        $subtree = drupal_render($subtree);
      }
      else {
        $subtree = '';
      }

      $id = str_replace(array('/', '<', '>'), array('-', '', ''), $item['href']);
      $subtrees[$id] = $subtree;
    }
  }
  return $subtrees;
}

/**
 * Checks whether an item is in the active trail.
 *
 * Useful when using a menu generated by menu_tree_all_data() which does
 * not set the 'in_active_trail' flag on items.
 *
 * @return
 *   TRUE when path is in the active trail, FALSE if not.
 *
 * @todo
 *   Look at migrating to a menu system level function.
 */
function toolbar_in_active_trail($path) {
  $active_paths = &drupal_static(__FUNCTION__);

  // Gather active paths.
  if (!isset($active_paths)) {
    $active_paths = array();
    $trail = menu_get_active_trail();
    foreach ($trail as $item) {
      if (!empty($item['href'])) {
        $active_paths[] = $item['href'];
      }
    }
  }
  return in_array($path, $active_paths);
}

/**
 * Implements hook_library_info().
 */
function toolbar_library_info() {
  $libraries['toolbar'] = array(
    'title' => 'Toolbar',
    'version' => VERSION,
    'js' => array(
      drupal_get_path('module', 'toolbar') . '/js/toolbar.js' => array(),
    ),
    'css' => array(
      drupal_get_path('module', 'toolbar') . '/css/toolbar.base.css',
      drupal_get_path('module', 'toolbar') . '/css/toolbar.theme.css',
      drupal_get_path('module', 'toolbar') . '/css/toolbar.icons.css',
    ),
    'dependencies' => array(
      array('system', 'jquery'),
      array('system', 'drupal'),
      array('system', 'drupalSettings'),
      array('system', 'matchmedia'),
      array('system', 'jquery.once'),
      array('system', 'drupal.debounce'),
      array('toolbar', 'toolbar.menu'),
    ),
  );

  $libraries['toolbar.menu'] = array(
    'title' => 'Toolbar nested accordion menus.',
    'version' => VERSION,
    'js' => array(
      drupal_get_path('module', 'toolbar') . '/js/toolbar.menu.js' => array(),
    ),
    'css' => array(
      drupal_get_path('module', 'toolbar') . '/css/toolbar.menu.css',
    ),
    'dependencies' => array(
      array('system', 'jquery'),
      array('system', 'drupal'),
      array('system', 'jquery.once'),
    ),
  );

  return $libraries;
}

/**
 * Implements hook_cache_flush().
 */
function toolbar_cache_flush() {
  return array('toolbar');
}

/**
 * Returns the hash of the per-user rendered toolbar subtrees.
 */
function _toolbar_get_subtree_hash() {
  global $user;
  $cid = $user->uid . ':' . language(LANGUAGE_TYPE_INTERFACE)->langcode;
  if ($cache = cache('toolbar')->get($cid)) {
    $hash = $cache->data;
  }
  else {
    $subtrees = toolbar_get_rendered_subtrees();
    $hash = drupal_hash_base64(serialize($subtrees));
    cache('toolbar')->set($cid, $hash);
  }
  return $hash;
}