common_design.theme

<?php

/**
 * @file
 * Template overrides, preprocess, and hooks for the OCHA Common Design theme.
 */

use Drupal\Core\Access\AccessResult;
use Drupal\Core\Cache\CacheableMetadata;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Template\Attribute;
use Drupal\Core\Url;

/**
 * Implements hook_form_system_theme_settings_alter().
 *
 * Add a setting to the theme for the special handling of the node title.
 *
 * Add a setting to enable extra fonts.
 */
function common_design_form_system_theme_settings_alter(&$form, FormStateInterface $form_state, $form_id = NULL) {
  // Work-around for a core bug affecting admin themes. See issue #943212.
  if (isset($form_id)) {
    return;
  }

  if (!isset($form['common_design'])) {
    $form['common_design'] = [
      '#type' => 'details',
      '#title' => t('Common design settings'),
      '#open' => TRUE,
    ];
  }

  // Add a setting to use light/dark favicons.
  $form['common_design']['use_light_dark_favicon'] = [
    '#type'          => 'checkbox',
    '#title'         => t('Use light/dark favicon'),
    '#default_value' => theme_get_setting('use_light_dark_favicon') ?? FALSE,
  ];

  // Load the node view modes.
  $storage = \Drupal::entityTypeManager()->getStorage('entity_view_mode');
  $view_modes = $storage->loadByProperties([
    'targetEntityType' => 'node',
  ]);
  if (empty($view_modes)) {
    return;
  }

  // The view mode ids are in the form `node.viewmode` which is not a valid
  // key for the form options, so we strip the `node.`.
  $options = [];
  foreach ($view_modes as $view_mode) {
    $id = preg_replace('/^node\./', '', $view_mode->id());
    $options[$id] = $view_mode->label();
  }

  // By default, this behavior is enabled for the "full" view mode.
  $default = theme_get_setting('common_design_node_title');
  if (empty($default) && isset($options['full'])) {
    $default = ['full'];
  }

  $form['common_design']['common_design_node_title'] = [
    '#type'          => 'checkboxes',
    '#title'         => t('Use node title for view mode'),
    '#options'       => $options,
    '#default_value' => $default,
    '#description'   => t('Select the <strong>page</strong> node view modes for which to use the node title rather than the global page title block.'),
  ];

  // Theme and library services.
  $theme_handler = \Drupal::service('theme_handler');
  $library_discovery = \Drupal::service('library.discovery');

  // Get the installed themes.
  /** @var \Drupal\Core\Extension\Extension[] $theme_list */
  $theme_list = $theme_handler->listInfo();

  // Get the name of the active theme.
  $active_theme = \Drupal::theme()->getActiveTheme()->getName();

  // Themes from which to extract the font libraries.
  $themes = [];

  // Get the name of the base theme. If it's the common design one, then we
  // add it to the list of themes.
  $base_theme = $theme_list[$active_theme]->base_theme;
  if ($base_theme === 'common_design' && isset($theme_list[$base_theme])) {
    $themes[$base_theme] = $theme_list[$base_theme];
  }

  // Add the active theme (after the base theme).
  $themes[$active_theme] = $theme_list[$active_theme];

  // Extract the font libraries.
  $fonts_options = [];
  foreach ($themes as $theme_name => $theme_extension) {
    // Get the list of libraries defined in the theme's libaries.yml.
    $libraries = $library_discovery->getLibrariesByExtension($theme_name);

    foreach ($libraries as $name => $info) {
      // @todo we could add a "tags" property instead for example.
      if (strpos($name, 'fonts-') === 0) {
        $value = $theme_name . '/' . $name;
        // We prefix the label with the theme name to differentiate between
        // libraries from the common design base theme and the ones from the
        // subtheme.
        $label = implode(' - ', [
          $theme_extension->info['name'],
          $info['label'] ?? ucfirst(substr($name, 6)),
        ]);
        $fonts_options[$value] = $label;
      }
    }
  }

  if (!empty($fonts_options)) {
    $form['common_design']['common_design_fonts'] = [
      '#type'          => 'checkboxes',
      '#title'         => t('Enable fonts'),
      '#options'       => $fonts_options,
      '#default_value' => theme_get_setting('common_design_fonts') ?? [],
    ];
  }
}

/**
 * Implements hook_preprocess().
 */
function common_design_preprocess(&$variables, $hook) {
  try {
    $variables['is_front'] = \Drupal::service('path.matcher')->isFrontPage();
  }
  catch (Exception $e) {
    $variables['is_front'] = FALSE;
  }
  // Ensure the cache varies correctly.
  $variables['#cache']['contexts'][] = 'url.path.is_front';

  // Check if Components module is enabled, to prevent page--demo.html.twig
  // breaking due to twig errors.
  $moduleHandler = \Drupal::service('module_handler');
  if ($moduleHandler->moduleExists('components')) {
    $variables['componentsModule'] = TRUE;
  }
}

/**
 * Indicate whether to render the page title inside the node or not.
 *
 * @param string $view_mode
 *   View mode to check against the theme settings.
 *
 * @return bool
 *   TRUE if the page title should be rendered inside the node.
 */
function common_design_use_node_page_title($view_mode) {
  if (empty($view_mode)) {
    return FALSE;
  }

  // Get the list of node view modes for which to use the pre-rendered page
  // title instead of the normal page title block. This is an associative array
  // keyed by view modes and with either the view mode as value when enabled
  // or 0 otherwise. If not set, enable the behavior for the full view-mode.
  $view_modes = theme_get_setting('common_design_node_title');
  if (!isset($view_modes)) {
    $view_modes = ['full' => 'full'];
  }

  return !empty($view_modes[$view_mode]);
}

/**
 * Implements hook_preprocess_page().
 *
 * Remove the default page title and local tasks blocks if they were already
 * rendered by a page title paragraph or when viewing full article nodes.
 *
 * Attach the selected fonts libraries.
 */
function common_design_preprocess_page(&$variables) {
  $route_match = \Drupal::routeMatch();
  $route_name = $route_match->getRouteName();

  // Retrieve the view mode for the node page or preview page.
  $view_mode = '';
  if ($route_name === 'entity.node.canonical') {
    $node = $route_match->getParameter('node');
    if (!empty($node)) {
      // This gives us an array with the page view mode for the node.
      $build = \Drupal::entityTypeManager()
        ->getViewBuilder('node')
        ->view($node);

      $view_mode = $build['#view_mode'] ?? '';
    }
  }
  elseif ($route_name === 'entity.node.preview') {
    $view_mode = $route_match->getParameter('view_mode_id');
  }

  // If the view mode was selected to use the page title block, then
  // we remove the original page title block and local tasks blocks.
  // @see common_design_preprocess_node().
  // @see common_design_set_page_title().
  if (common_design_use_node_page_title($view_mode)) {
    if ($route_name === 'entity.node.canonical') {
      common_design_hide_rendered_blocks_from_page($variables, [
        'page_title_block',
        'local_tasks_block',
      ]);
    }
    elseif ($route_name === 'entity.node.preview') {
      common_design_hide_rendered_blocks_from_page($variables, [
        'page_title_block',
      ]);
    }
  }

  // Extra fronts to enable.
  $fonts = theme_get_setting('common_design_fonts') ?? [];
  foreach ($fonts as $name => $enabled) {
    if (!empty($enabled)) {
      $variables['#attached']['library'][] = $name;
    }
  }
}

/**
 * Implements hook_preprocess_node().
 *
 * Use the page title block for the node title if the view mode was selected
 * in the theme settings.
 *
 * Important: this assumes there is a template for the view mode that uses
 * the `title` (and `local_tasks`) variables added by
 * common_design_use_node_page_title(). See `node--full.html.twig`.
 *
 * @see common_design_preprocess_page()
 * @see common_design_set_page_title()
 */
function common_design_preprocess_node(&$variables) {
  $route_name = \Drupal::routeMatch()->getRouteName();

  $node = $variables['node'] ?? NULL;
  $view_mode = $variables['view_mode'] ?? '';

  // If the node view mode was selected to use the page title block for the
  // node title in the template, then we add the page title to the template
  // variables. We only do that if we are on the canonical node page or on
  // the node preview page.
  if (isset($node) && common_design_use_node_page_title($view_mode)) {
    if (node_is_page($node)) {
      common_design_set_page_title($variables, $node->label(), TRUE);
    }
    elseif ($node->in_preview && $route_name === 'entity.node.preview') {
      common_design_set_page_title($variables, $node->label(), FALSE);
    }
  }
}

/**
 * Set the page title (ex: node page) using the page title block.
 *
 * @param array $variables
 *   Variables as passed to a hook_preprocess_HOOK().
 * @param string $default_title
 *   Default title to use if none can be resolved.
 * @param bool $is_page
 *   Flag indicating if we are on a normal page as opposed to viewing an entity
 *   in preview for example, or if this called outside of a page context.
 */
function common_design_set_page_title(array &$variables, $default_title, $is_page = FALSE) {
  // Retrieve the page title block.
  $variables['title'] = common_design_get_block_render_array('page_title_block');
  if (!empty($variables['title'])) {
    // If we are on a normal page (not in a node preview for example), and the
    // page title render array doesn't have a default title, then we try to get
    // the title from the title resolver service.
    // @see https://www.drupal.org/project/drupal/issues/2938129
    if ($is_page) {
      if (empty($variables['title']['#title'])) {
        $request = \Drupal::request();
        $route_object = \Drupal::routeMatch()->getRouteObject();
        if (!empty($request) && !empty($route_object)) {
          $default_title = \Drupal::service('title_resolver')
            ->getTitle($request, $route_object);
        }
      }
      else {
        $default_title = $variables['title']['#title'];
      }
    }

    // Set the default title.
    $variables['title']['#title'] = $default_title;

    // Copy the title attributes.
    if (!empty($variables['title_attributes'])) {
      $variables['title']['#title_attributes'] = $variables['title_attributes'];
    }
  }

  // Also pre-render the local tasks when on a normal page.
  if ($is_page) {
    $variables['local_tasks'] = common_design_get_block_render_array('local_tasks_block');
  }
}

/**
 * Implements hook_theme_registry_alter().
 *
 * Ensure we can set the title attributes to the page title.
 */
function common_design_theme_registry_alter(&$theme_registry) {
  if (isset($theme_registry['page_title'])) {
    $theme_registry['page_title']['variables']['title_attributes'] = [];
  }

  // The theme discovery (drupal_find_theme_templates()) is too greedy and
  // picks up the templates in `common_design/common_design_subtheme`. The code
  // below reverts that behavior to use the `common_design` templates instead.
  foreach ($theme_registry as $name => $theme_info) {
    if (isset($theme_info['path']) && strpos($theme_info['path'], 'common_design/common_design_subtheme') !== FALSE) {
      $theme_registry[$name]['path'] = str_replace('common_design/common_design_subtheme', 'common_design', $theme_info['path']);
    }
  }
}

/**
 * Impements hook_theme_suggestions_input_alter().
 */
function common_design_theme_suggestions_input_alter(&$suggestions, array $variables) {
  $element = $variables['element'];

  if (isset($element['#attributes']['data-twig-suggestion'])) {
    $suggestions[] = 'input__' . $element['#type'] . '__' . $element['#attributes']['data-twig-suggestion'];
  }
}

/**
 * Impements hook_theme_suggestions_form_alter().
 */
function common_design_theme_suggestions_form_alter(array &$suggestions, array $variables) {
  $suggestions[] = 'form__' . $variables['element']['#form_id'];
}

/**
 * Impements hook_theme_suggestions_form_element_alter().
 */
function common_design_theme_suggestions_form_element_alter(array &$suggestions, array $variables, $hook) {
  $suggestions[] = $hook . '__' . $variables['element']['#type'];
}

/**
 * Implements hook_theme_suggestions_paragraph_alter().
 *
 * - paragraph--PARENT-ENTITY--PARAGRAPH.html.twig
 * - paragraph--PARENT-ENTITY--PARENT-FIELD--PARAGRAPH.html.twig
 */
function common_design_theme_suggestions_paragraph_alter(array &$suggestions, array $variables) {
  $paragraph = $variables['elements']['#paragraph'];
  $parent_entity = $paragraph->getParentEntity();
  $parent_field_name = $paragraph->parent_field_name->value;

  if ($parent_entity) {
    $suggestions[] = 'paragraph__' . $parent_entity->bundle() . '__' . $paragraph->bundle();
  }
  if ($parent_entity && $parent_field_name) {
    $suggestions[] = 'paragraph__' . $parent_entity->bundle() . '__' . $parent_field_name . '__' . $paragraph->bundle();
  }
}

/**
 * Implements hook_form_alter().
 */
function common_design_form_alter(&$form, FormStateInterface $form_state, $form_id) {

  // This is for Drupal core search block.
  if ($form_id == 'search_block_form') {
    $form['#attributes']['class'][] = 'cd-search__form';
    $form['#attributes']['aria-labelledby'][] = 'cd-search-form';
    $form['#attributes']['data-cd-toggable'][] = 'Search';
    $form['#attributes']['data-cd-icon'][] = '';
    $form['#attributes']['data-cd-component'][] = 'cd-search';
    $form['#attributes']['data-cd-logo'][] = 'search';
    // Focus the input when clicking on the toggler button.
    $form['#attributes']['data-cd-focus-target'] = 'cd-search';
    $form['keys']['#attributes']['placeholder'][] = t('What are you looking for?');
    $form['keys']['#attributes']['class'][] = 'cd-search__input';
    $form['keys']['#attributes']['id'][] = 'cd-search';
    $form['keys']['#attributes']['autocomplete'][] = 'off';
    // Theme suggestion for submit element.
    $form['actions']['submit']['#attributes']['data-twig-suggestion'] = 'search_submit';
    $form['actions']['submit']['#attributes']['class'][] = 'cd-search__submit';
    $form['actions']['submit']['#attributes']['value'][] = 'Search';

    // This is for a Drupal core INLINE search block.
    // There are templates needed for this. Replace cd-search.html.twig
    // with cd-search--inline.html.twig in cd-site-header.html.twig.
    // @codingStandardsIgnoreStart
    /*
    $form['#attributes']['class'][] = 'cd-search--inline__form';
    $form['#attributes']['aria-labelledby'][] = 'cd-search-form--inline';
    $form['#attributes']['data-cd-toggable'][] = 'Search';
    $form['#attributes']['data-cd-icon'][] = '';
    $form['#attributes']['data-cd-component'][] = 'cd-search--inline';
    $form['#attributes']['data-cd-logo'][] = 'search';
    // Focus the input when clicking on the toggler button.
    $form['#attributes']['data-cd-focus-target'] = 'cd-search--inline';
    $form['keys']['#attributes']['placeholder'][] = t('What are you looking for?');
    $form['keys']['#attributes']['class'][] = 'cd-search--inline__input';
    $form['keys']['#attributes']['type'][] = 'search';
    $form['keys']['#attributes']['id'][] = 'cd-search--inline';
    $form['keys']['#attributes']['autocomplete'][] = 'off';
    // Theme suggestion for submit element.
    $form['actions']['submit']['#attributes']['data-twig-suggestion'] = 'search_submit';
    $form['actions']['submit']['#attributes']['class'][] = 'cd-search--inline__submit';
    $form['actions']['submit']['#attributes']['value'][] = 'Search';
    */
    // @codingStandardsIgnoreEnd
  }

  // To use this for Views exposed forms, copy the form alter hook into your
  // subtheme and add the relevant Views IDs to this array in your subtheme.
  $includeView = [];

  // If in array above, add attributes for styling and behaviour.
  // Replace $form['keys'] with the appropriate fulltext input eg.
  // $form['search_api_fulltext'].
  if (in_array($form['#id'], $includeView)) {
    $form['#attributes']['class'][] = 'cd-search__form';
    $form['#attributes']['aria-labelledby'][] = 'cd-search-form';
    $form['#attributes']['data-cd-toggable'][] = 'Search';
    $form['#attributes']['data-cd-icon'][] = '';
    $form['#attributes']['data-cd-component'][] = 'cd-search';
    $form['#attributes']['data-cd-logo'][] = 'search';
    // Focus the input when clicking on the toggler button.
    $form['#attributes']['data-cd-focus-target'] = 'cd-search';
    $form['keys']['#attributes']['placeholder'] = t('What are you looking for?');
    $form['keys']['#attributes']['class'][] = 'cd-search__input';
    $form['keys']['#attributes']['type'][] = 'search';
    $form['keys']['#attributes']['id'][] = 'cd-search';
    $form['keys']['#attributes']['autocomplete'][] = 'off';
    // Theme suggestion for submit element.
    $form['actions']['submit']['#attributes']['data-twig-suggestion'] = 'search_submit';
    $form['actions']['submit']['#attributes']['class'][] = 'cd-search__submit';
    $form['actions']['submit']['#attributes']['value'][] = 'Search';

    // This is for a Views exposed form INLINE search block.
    // There are templates needed for this. Replace cd-search.html.twig
    // with cd-search--inline.html.twig in cd-site-header.html.twig.
    // @codingStandardsIgnoreStart
    /*
    $form['#attributes']['class'][] = 'cd-search--inline__form';
    $form['#attributes']['aria-labelledby'][] = 'cd-search-form--inline';
    $form['#attributes']['data-cd-toggable'][] = 'Search';
    $form['#attributes']['data-cd-icon'][] = '';
    $form['#attributes']['data-cd-component'][] = 'cd-search--inline';
    $form['#attributes']['data-cd-logo'][] = 'search';
    // Focus the input when clicking on the toggler button.
    $form['#attributes']['data-cd-focus-target'] = 'cd-search--inline';
    $form['keys']['#attributes']['placeholder'][] = t('What are you looking for?');
    $form['keys']['#attributes']['class'][] = 'cd-search--inline__input';
    $form['keys']['#attributes']['type'][] = 'search';
    $form['keys']['#attributes']['id'][] = 'cd-search--inline';
    $form['keys']['#attributes']['autocomplete'][] = 'off';
    // Theme suggestion for submit element.
    $form['actions']['submit']['#attributes']['data-twig-suggestion'] = 'search_submit';
    $form['actions']['submit']['#attributes']['class'][] = 'cd-search--inline__submit';
    $form['actions']['submit']['#attributes']['value'][] = 'Search';
    */
    // @codingStandardsIgnoreEnd
  }

  /* Add CD button classes to Cancel and Delete */
  if (isset($form['actions']['delete'])) {
    if ($form['actions']['delete']['#button_type'] == 'danger') {
      $form['actions']['delete']['#attributes']['class'][] = 'cd-button cd-button--danger';
    }
  }

  /* Add CD button classes to Delete and Cancel on Node/Term confirmation pages */
  if ($form['#theme'] == 'confirm_form') {
    if (isset($form['actions']['submit'])) {
      if ($form['actions']['submit']['#button_type'] == 'primary') {
        $form['actions']['submit']['#attributes']['class'][] = 'cd-button cd-button--danger';
      }
    }
    if (isset($form['actions']['cancel'])) {
      if ($form['actions']['cancel']['#type'] == 'link') {
        $form['actions']['cancel']['#attributes']['class'][] = 'cd-button cd-button--outline';
      }
    }
  }
}

/**
 * Implements hook_preprocess_html().
 */
function common_design_preprocess_html(&$vars) {
  // Check if current request is an exception to get error type.
  $status_code = \Drupal::requestStack()->getCurrentRequest()->attributes->get('exception');

  // Add body classes.
  if ($status_code && !is_a($status_code, 'ParamNotConvertedException')) {
    if ($status_code->getStatusCode() == 404) {
      $vars['attributes']['class'][] = 'path-error path-error--404';
    }
    if ($status_code->getStatusCode() == 403) {
      $vars['attributes']['class'][] = 'path-error path-error--403';
    }
  }

  // Add a script to detect whether javascript is enabled or not and then
  // replace the `no-js` class with the `js` one.
  //
  // Drupal.js does this but way too late on first load causing issues with
  // css rules that rely on the `js` class being defined or not.
  //
  // @TODO: we end up with duplicate `js` classes when both this and Drupal.js
  //        execute their code. It's also possible to see both `no-js` and `js`
  //        in old browsers like IE11.
  $js_detection = [
    '#tag' => 'script',
    '#value' => "document.documentElement.className = document.documentElement.className.replace('no-js', typeof document.addEventListener !== 'undefined' ? 'js' : 'no-js');",
    '#weight' => -1,
  ];
  $vars['page']['#attached']['html_head'][] = [$js_detection, 'js-detection'];

  // Construct <link>s for Roboto: two that preconnect to Google Fonts, for a
  // nominal performance improvement, and the link to the CSS file itself.
  //
  // To load the font in a totally non-blocking manner, we are using the media
  // attribute to specify print until the fonts load, then we remove it with JS.
  // There is no <noscript> in place, so the fonts won't load on non-JS browsers
  // by design.
  //
  // To edit the font selection, visit the following URL:
  //
  // @see https://fonts.google.com/share?selection.family=Roboto:ital,wght@0,300;0,400;0,500;0,700;0,900;1,400;1,700
  $preconnect_api = [
    'rel' => 'preconnect',
    'href' => 'https://fonts.googleapis.com',
  ];
  $preconnect_static = [
    'rel' => 'preconnect',
    'href' => 'https://fonts.gstatic.com',
    'crossorigin' => TRUE,
  ];
  $roboto_default = [
    'rel' => 'preload',
    'href' => 'https://fonts.googleapis.com/css2?family=Roboto:ital,wght@0,300;0,400;0,500;0,700;0,900;1,400;1,700&display=swap',
    'as' => 'style',
    'onload' => 'this.onload=null;this.setAttribute(`rel`, `stylesheet`);',
  ];

  // Add <link>s to HTML response.
  $vars['page']['#attached']['html_head_link'][] = [
    $preconnect_api,
    'preconnect-api',
  ];
  $vars['page']['#attached']['html_head_link'][] = [
    $preconnect_static,
    'preconnect-static',
  ];
  $vars['page']['#attached']['html_head_link'][] = [
    $roboto_default,
    'roboto-default',
  ];
}

/**
 * Implements hook_theme_suggestions_HOOK_alter().
 *
 * - page--demo.html.twig
 * - page--401.html.twig
 * - page--403.html.twig
 * - page--404.html.twig
 */
function common_design_theme_suggestions_page_alter(array &$suggestions, array $variables, $hook) {
  $current_uri = \Drupal::request()->getRequestUri();
  // Set variable based on path alias to include Component demo page.
  if ($current_uri == '/demo') {
    $suggestions[] = $hook . '__demo';
  }

  // Error page template suggestions.: 401, 403, 404, etc
  if (!is_null(Drupal::requestStack()->getCurrentRequest()->attributes->get('exception'))) {
    $status_code = Drupal::requestStack()->getCurrentRequest()->attributes->get('exception')->getStatusCode();
    $suggestions[] = 'page__' . (string) $status_code;
  }
}

/**
 * Implements hook_theme_suggestions_HOOK_alter().
 *
 * Provides more granularity when Views displays are getting rendered. The two
 * suggestions will allow the following templates to be picked up:
 *
 * - views-view--VIEW.html.twig
 * - views-view--VIEW--DISPLAY.html.twig
 *
 * @see https://api.drupal.org/api/drupal/core%21lib%21Drupal%21Core%21Render%21theme.api.php/function/hook_theme_suggestions_HOOK_alter/8.8.x
 */
function common_design_theme_suggestions_views_view_alter(&$suggestions, $variables) {
  $suggestions[] = sprintf('views_view__%s', $variables['view']->id());
  $suggestions[] = sprintf('views_view__%s__%s', $variables['view']->id(), $variables['view']->current_display);
}

/**
 * Implements hook_block__language_block().
 */
function common_design_preprocess_block__language_block(&$vars) {
  // Current language available in template override.
  $language = \Drupal::languageManager()->getCurrentLanguage()->getId();
  $vars['language'] = $language;

  $language_name = \Drupal::languageManager()->getCurrentLanguage()->getName();
  $vars['language_name'] = $language_name;
}

/**
 * Implements hook_preprocess_menu().
 *
 * Ensure we have a user menu hierarchy in the form:
 *
 * My account
 *   Edit my account
 *   ... (potential other menu items)
 *   Log out
 */
function common_design_preprocess_menu__account(&$variables) {
  $items = &$variables['items'] ?? [];

  $base_child_menu_item = [
    'is_expanded' => FALSE,
    'is_collapsed' => FALSE,
    'in_active_trail' => FALSE,
    'attributes' => new Attribute(),
    'below' => [],
  ];

  // Find the "My account" menu item. It may be the default system menu item
  // from the core user module or a custom one added as per release instructions
  // of the CD 7.4 version.
  foreach ($items as &$item) {
    if (isset($item['url']) && $item['url']->isRouted() && $item['url']->getRouteName() === 'user.page') {
      $account_menu_item = &$item;
      break;
    }
  }

  // If there is a menu account, add a child link to the user edit form (or
  // user page for Drupal < 9.5) and a child link to log out; and consolidate
  // the labels.
  if (isset($account_menu_item)) {
    $children = $account_menu_item['below'] ?? [];

    // Retrieve or create a link to the user page. This is mostly for backward
    // compatibility with the CD 7.4.
    if (isset($children['user.page'])) {
      $user_edit_menu_item = $children['user.page'];
      unset($children['user.page']);
    }
    else {
      $user_edit_menu_item = $base_child_menu_item;
    }

    // For Drupal 9.5+, we redirect to the user edit form.
    if (!empty(\Drupal::service('router')->getRouteCollection()->get('user.edit'))) {
      $user_edit_menu_item['url'] = Url::fromRoute('user.edit');
    }
    elseif (!isset($user_edit_menu_item['url'])) {
      $user_edit_menu_item['url'] = Url::fromRoute('user.page');
    }

    // Ensure the title is consistent across sites using the CD.
    $user_edit_menu_item['title'] = t('Edit my account');

    // Add it as the first link.
    $children = ['user.page' => $user_edit_menu_item] + $children;

    // Retrieve any existing logout link. This is mostly for backward
    // compatibility with the CD 7.4 and prevents multiple logout links.
    foreach ($children as $key => $child) {
      if (isset($child['url']) && $child['url']->isRouted() && $child['url']->getRouteName() === 'user.logout') {
        $logout_menu_item = $child;
        unset($children[$key]);
      }
    }

    // Use the top logout link if it exists.
    if (isset($items['user.logout'])) {
      $logout_menu_item = $items['user.logout'];
      unset($items['user.logout']);
    }
    // Otherwise create a new one if we didn't find one earlier.
    elseif (!isset($logout_menu_item)) {
      $logout_menu_item = $base_child_menu_item + [
        'url' => Url::fromRoute('user.logout'),
      ];
    }

    // Ensure the title is consistent across sites using the CD.
    $logout_menu_item['title'] = t('Log out');

    // Add the link at the bottom.
    $children['user.logout'] = $logout_menu_item;

    // Mark the menu item as expanded so it's converted to a button.
    $account_menu_item['is_expanded'] = TRUE;
    $account_menu_item['below'] = $children;

    // Ensure the title is consistent across sites using the CD.
    $account_menu_item['title'] = t('My account');
  }
}

/**
 * Load the block entities for the given ids.
 *
 * @param array $ids
 *   Block ids.
 *
 * @return \Drupal\block\BlockInterface[]
 *   Block entities.
 */
function common_design_load_theme_blocks(array $ids) {
  if (empty($ids)) {
    return [];
  }

  $storage = \Drupal::entityTypeManager()->getStorage('block');
  $theme = \Drupal::theme()->getActiveTheme();

  // Load the blocks with that plugin id for the theme.
  return $storage->loadByProperties([
    'theme' => $theme->getName(),
    'plugin' => $ids,
  ]);
}

/**
 * Render a block.
 *
 * We store the list of blocks rendered by this function so that we can
 * prevent them from being rendered several times on a page.
 *
 * @param string $id
 *   Block ID.
 *
 * @return array
 *   Renderable array of the block. Empty array if this was already called
 *   before to avoid displaying the block several times.
 */
function common_design_get_block_render_array($id) {
  $rendered = &drupal_static(__FUNCTION__, []);

  if (!isset($rendered[$id])) {
    // Prevent rendering the block several times.
    $rendered[$id] = TRUE;

    // Load the blocks with that plugin id for the theme.
    $blocks = common_design_load_theme_blocks([$id]);
    if (empty($blocks)) {
      return [];
    }

    // Get the render array for the block.
    $block = reset($blocks);
    $build = $block->getPlugin()->build();

    // Check the accessibility to the block.
    $build['#access'] = $block->access('view', NULL, TRUE);

    // Ensure the appropriate cache metadata is added to the build.
    $cache = CacheableMetadata::createFromRenderArray($build);
    $cache->addCacheableDependency($block);
    $cache->addCacheableDependency($build['#access']);
    $cache->applyTo($build);

    // The local tasks have by default a max-age cache of 0 which prevents the
    // entire caching so we remove it as there are already cache contexts and
    // tags to ensure its displayed appropriately.
    if ($id === 'local_tasks_block' && empty($build['#cache']['max-age'])) {
      unset($build['#cache']['max-age']);
    }

    return $build;
  }

  return [];
}

/**
 * Remove already rendered blocks from the page.
 *
 * @param array $variables
 *   Page variables as passed to hook_preprocess_page().
 * @param array $block_ids
 *   Ids of the blocks to hide.
 */
function common_design_hide_rendered_blocks_from_page(array &$variables, array $block_ids) {
  $blocks = common_design_load_theme_blocks($block_ids);
  if (!empty($blocks)) {
    foreach ($blocks as $block) {
      $id = $block->id();
      $region = $block->getRegion();

      // If the block exists in the page, then deny access to it so that it's
      // hidden. We don't remove the block so that access and visibility can
      // be restored by other modules/sub-themes.
      if (isset($variables['page'][$region][$id])) {
        $access = $variables['page'][$region][$id]['#access'] ?? NULL;
        // Store the original access information so that other modules that
        // want to undo what is done here can do so.
        $variables['page'][$region][$id]['#original_access'] = $access;

        // Deny access to hide the block. We use the function name as reason
        // so that it's easy for modules/sub-themes that want to revert the
        // behavior to identify blocks that have been denied access this way.
        $forbidden = AccessResult::forbidden(__FUNCTION__);
        if ($access instanceof AccessResult) {
          // This preserves the cache metadata of the previous access result.
          $access = $access->andIf($forbidden);
        }
        else {
          $access = $forbidden;
        }
        $variables['page'][$region][$id]['#access'] = $access;
      }
    }
  }
}

/**
 * Implements hook_theme().
 *
 * Add themes for the taxonomy term and user edit forms.
 */
function common_design_theme(array $existing, $type, $theme, $path) {
  $hooks = [
    'taxonomy_term_edit_form',
    'user_edit_form',
  ];

  return common_design_get_entity_edit_form_themes($hooks, $existing, $theme, $path);
}

/**
 * Generate the list of themes for entity edit forms.
 *
 * @param array $hooks
 *   List of base edit form theme ids to create.
 * @param array $existing
 *   List of existing themes.
 * @param string $theme
 *   The current theme (ex: common_design) name.
 * @param string $path
 *   The path of the current theme.
 *
 * @return array
 *   Theme data as returned by hook_theme().
 */
function common_design_get_entity_edit_form_themes(array $hooks, array $existing, $theme, $path) {
  $themes = [];
  $scan = is_dir($path);
  foreach ($hooks as $hook) {
    // In case Drupal becomes consistent and adds the term and user edit form
    // themes like it does with the `node_edit_form` theme for nodes...
    if (isset($existing[$hook])) {
      continue;
    }

    // We need to explicitly add a preprocess function so that the
    // `preprocess functions` key is not removed in
    // \Drupal\Core\Theme\Registry::postProcessExtension()
    // which causes a PHP "null given" error when calling array_diff in
    // \Drupal\Core\Theme\Registry::mergePreprocessFunctions()...
    //
    // @see \Drupal\Core\Theme\Registry::postProcessExtension()
    // @see \Drupal\Core\Theme\Registry::mergePreprocessFunctions()
    $themes[$hook] = [
      'render element' => 'form',
      'path' => $path . '/templates/form',
      'preprocess functions' => [$theme . '_preprocess_' . $hook],
    ];

    // Drupal doesn't allow finding suggestions for themes declared in the
    // current theme's hook_theme. So we do a light scan to populate the theme
    // registry with suggestions.
    //
    // Note: we don't need to do that for the node_edit_form theme defined
    // in the core node module because it's not defined in this theme and
    // drupal_find_theme_templates() will pick the template override and
    // suggestions properly.
    //
    // @see drupal_find_theme_templates()
    // @see twig_theme()
    if ($scan) {
      $regex = '#(^|/)' . strtr($hook, '_', '-') . '--.*\.html\.twig$#';
      $files = \Drupal::service('file_system')->scanDirectory($path, $regex);
      foreach ($files as $file) {
        $template = str_replace('.html.twig', '', $file->filename);
        $suggestion = strtr($template, '-', '_');
        $themes[$suggestion] = [
          'render element' => 'form',
          'template' => $template,
          'path' => dirname($file->uri),
          'base hook' => $hook,
          'preprocess functions' => [$theme . '_preprocess_' . $suggestion],
        ];
      }
    }
  }

  return $themes;
}

/**
 * Add bundle and view mode theme suggestions for the edit form of an entity.
 *
 * @param array $form
 *   The form array.
 * @param \Drupal\Core\Form\FormStateInterface $form_state
 *   The form state.
 *
 * @see seven_form_node_form_alter()
 */
function common_design_add_entity_edit_form_theme(array &$form, FormStateInterface $form_state) {
  $display = $form_state->get('form_display');
  $entity_type_id = $display->getTargetEntityTypeId();
  $bundle = $display->getTargetBundle();
  $view_mode = $display->getMode();
  $base = $entity_type_id . '_edit_form';

  // The order is important.
  $form['#theme'][] = $base . '__' . $bundle . '__' . $view_mode;
  $form['#theme'][] = $base . '__' . $view_mode;
  $form['#theme'][] = $base . '__' . $bundle;
  $form['#theme'][] = $base;
}

/**
 * Implements hook_form_node_HOOK_alter().
 */
function common_design_form_node_form_alter(&$form, FormStateInterface $form_state) {
  common_design_add_entity_edit_form_theme($form, $form_state);
}

/**
 * Implements hook_form_node_HOOK_alter().
 */
function common_design_form_taxonomy_term_form_alter(&$form, FormStateInterface $form_state) {
  common_design_add_entity_edit_form_theme($form, $form_state);

  // Make the form page title consistent with the nodes to avoid the generic
  // "Add term" and "Edit term" page titles.
  if (!isset($form['#title'])) {
    $entity = $form_state->getFormObject()->getEntity();
    $bundle_key = $entity->getEntityType()->getKey('bundle');
    $bundle_label = $entity->get($bundle_key)->entity->label();

    if (empty($form['tid']['#value'])) {
      $form['#title'] = t('Create @bundle_label', [
        '@bundle_label' => $bundle_label,
      ]);
    }
    else {
      $form['#title'] = t('<em>Edit @bundle_label</em> @title', [
        '@bundle_label' => $bundle_label,
        '@title' => $entity->label(),
      ]);
    }
  }
}

/**
 * Implements hook_form_node_HOOK_alter().
 */
function common_design_form_user_form_alter(array &$form, FormStateInterface $form_state) {
  common_design_add_entity_edit_form_theme($form, $form_state);
}

/**
 * Implemenents hook_preprocess_fieldset().
 */
function common_design_preprocess_fieldset(array &$variables) {
  // Set the visually-hidden class to the legend element itself rather than
  // its span when the title is supposed to be hidden.
  // @see template_preprocess_fieldset()
  if ($variables['title_display'] === 'invisible') {
    $variables['legend']['attributes']->addClass('visually-hidden');
    $variables['legend_span']['attributes']->removeClass('visually-hidden');
  }
}

/**
 * Implements hook_preprocess_datetime_wrapper().
 */
function common_design_preprocess_datetime_wrapper(&$variables) {
  // Ensure the title is not displayed when instructed to be hidden.
  if (isset($variables['element']['#title_display']) && $variables['element']['#title_display'] === 'invisible') {
    $variables['title_attributes']['class'][] = 'visually-hidden';
  }
}

/**
 * Implements hook_page_attachments_alter().
 */
function common_design_page_attachments_alter(array &$page) {
  $active_theme = \Drupal::theme()->getActiveTheme();

  if (!theme_get_setting('use_light_dark_favicon')) {
    return;
  }

  // Attach blue favicon from active theme.
  if (file_exists($active_theme->getPath() . '/img/favicons/blue/favicon.ico')) {
    $page['#attached']['html_head_link'][][] = [
      'rel' => 'icon',
      'href' => '/' . $active_theme->getPath() . '/img/favicons/blue/favicon.ico',
      'type' => 'image/x-icon',
      'media' => '(prefers-color-scheme: light)',
    ];
  }
  else {
    // Attach favicon from parent theme.
    foreach ($active_theme->getBaseThemeExtensions() as $base_theme) {
      if (file_exists($base_theme->getPath() . '/img/favicons/blue/favicon.ico')) {
        $page['#attached']['html_head_link'][][] = [
          'rel' => 'icon',
          'href' => '/' . $base_theme->getPath() . '/img/favicons/blue/favicon.ico',
          'type' => 'image/x-icon',
          'media' => '(prefers-color-scheme: light)',
        ];
        break;
      }
    }
  }

  // Attach white favicon from active theme.
  if (file_exists($active_theme->getPath() . '/img/favicons/white/favicon.ico')) {
    $page['#attached']['html_head_link'][][] = [
      'rel' => 'icon',
      'href' => '/' . $active_theme->getPath() . '/img/favicons/white/favicon.ico',
      'type' => 'image/x-icon',
      'media' => '(prefers-color-scheme: dark)',
    ];
  }
  else {
    // Attach favicon from parent theme.
    foreach ($active_theme->getBaseThemeExtensions() as $base_theme) {
      if (file_exists($base_theme->getPath() . '/img/favicons/white/favicon.ico')) {
        $page['#attached']['html_head_link'][][] = [
          'rel' => 'icon',
          'href' => '/' . $base_theme->getPath() . '/img/favicons/white/favicon.ico',
          'type' => 'image/x-icon',
          'media' => '(prefers-color-scheme: dark)',
        ];

        break;
      }
    }
  }
}