class ToolbarThemeHooks

class ToolbarThemeHooks {
  public function __construct(protected RendererInterface $renderer, protected readonly ThemeHandlerInterface $themeHandler, protected readonly ThemeManagerInterface $themeManager, protected readonly AccountProxyInterface $currentUser, protected readonly ConfigFactoryInterface $configFactory) {
  }
  
  /**
   * Implements hook_theme().
   */
  public function theme($existing, $type, $theme, $path) : array {
    $items['toolbar'] = [
      'render element' => 'element',
      'initial preprocess' => static::class . ':preprocessToolbar',
    ];
    $items['menu__toolbar'] = [
      'base hook' => 'menu',
      'variables' => [
        'menu_name' => NULL,
        'items' => [],
        'attributes' => [],
      ],
    ];
    return $items;
  }
  
  /**
   * Prepares variables for administration toolbar templates.
   *
   * Default template: toolbar.html.twig.
   *
   * @param array $variables
   *   An associative array containing:
   *   - element: An associative array containing the properties and children of
   *     the tray. Properties used: #children, #attributes and #bar.
   */
  public function preprocessToolbar(array &$variables) : void {
    $element = $variables['element'];
    // Prepare the toolbar attributes.
    $variables['attributes'] = $element['#attributes'];
    $variables['toolbar_attributes'] = new Attribute($element['#bar']['#attributes']);
    $variables['toolbar_heading'] = $element['#bar']['#heading'];
    // Prepare the trays and tabs for each toolbar item as well as the remainder
    // variable that will hold any non-tray, non-tab elements.
    $variables['trays'] = [];
    $variables['tabs'] = [];
    $variables['remainder'] = [];
    foreach (Element::children($element) as $key) {
      // Early rendering to collect the wrapper attributes from
      // ToolbarItem elements.
      if (!empty($element[$key])) {
        $this->renderer
          ->render($element[$key]);
      }
      // Add the tray.
      if (isset($element[$key]['tray'])) {
        $attributes = [];
        if (!empty($element[$key]['tray']['#wrapper_attributes'])) {
          $attributes = $element[$key]['tray']['#wrapper_attributes'];
        }
        $variables['trays'][$key] = [
          'links' => $element[$key]['tray'],
          'attributes' => new Attribute($attributes),
        ];
        if (array_key_exists('#heading', $element[$key]['tray'])) {
          $variables['trays'][$key]['label'] = $element[$key]['tray']['#heading'];
        }
      }
      // Add the tab.
      if (isset($element[$key]['tab'])) {
        $attributes = [];
        // Pass the wrapper attributes along.
        if (!empty($element[$key]['#wrapper_attributes'])) {
          $attributes = $element[$key]['#wrapper_attributes'];
        }
        $variables['tabs'][$key] = [
          'link' => $element[$key]['tab'],
          'attributes' => new Attribute($attributes),
        ];
      }
      // Add other non-tray, non-tab child elements to the remainder variable
      // for later rendering.
      foreach (Element::children($element[$key]) as $child_key) {
        if (!in_array($child_key, [
          'tray',
          'tab',
        ])) {
          $variables['remainder'][$key][$child_key] = $element[$key][$child_key];
        }
      }
    }
  }
  
  /**
   * Implements hook_preprocess_HOOK() for HTML document templates.
   */
  public function preprocessHtml(&$variables) : void {
    if (!$this->currentUser
      ->hasPermission('access toolbar')) {
      return;
    }
    $variables['attributes']['class'][] = 'toolbar-loading';
  }
  
  /**
   * Implements hook_preprocess_toolbar().
   */
  public function preprocessToolbarForClaro(array &$variables, $hook, $info) : void {
    // When Claro is the admin theme, Claro overrides the active theme's if that
    // active theme is not Claro. Because of these potential overrides, the
    // toolbar cache should be invalidated any time the default or admin theme
    // changes.
    $variables['#cache']['tags'][] = 'config:system.theme';
    // If Claro is the admin theme but not the active theme, still include
    // Claro's toolbar preprocessing.
    if ($this->isClaroAdminAndNotActive()) {
      $variables['attributes']['data-drupal-claro-processed-toolbar'] = TRUE;
    }
  }
  
  /**
   * Implements hook_library_info_alter().
   */
  public function libraryInfoAlter(&$libraries, $extension) : void {
    // If Claro is the admin theme but not the active theme, grant Claro the
    // ability to override the toolbar library with its own assets.
    if ($extension === 'toolbar' && $this->isClaroAdminAndNotActive()) {
      // If the active theme is not Claro, but Claro is the admin theme, this
      // alters the toolbar library config so Claro's toolbar stylesheets are
      // used.
      $claro_info = $this->themeHandler
        ->listInfo()['claro']->info;
      $path_prefix = '/core/themes/claro/';
      $claro_toolbar_overrides = $claro_info['libraries-override']['toolbar/toolbar'];
      foreach ($claro_toolbar_overrides['css'] as $concern => $overrides) {
        foreach ($claro_toolbar_overrides['css'][$concern] as $key => $value) {
          $config = $libraries['toolbar']['css'][$concern][$key];
          $libraries['toolbar']['css'][$concern][$path_prefix . $value] = $config;
          unset($libraries['toolbar']['css'][$concern][$key]);
        }
      }
      $claro_toolbar_menu_overrides = $claro_info['libraries-override']['toolbar/toolbar.menu'];
      foreach ($claro_toolbar_menu_overrides['css'] as $concern => $overrides) {
        foreach ($claro_toolbar_menu_overrides['css'][$concern] as $key => $value) {
          $config = $libraries['toolbar.menu']['css'][$concern][$key];
          $libraries['toolbar.menu']['css'][$concern][$path_prefix . $value] = $config;
          unset($libraries['toolbar.menu']['css'][$concern][$key]);
        }
      }
    }
  }
  
  /**
   * Implements hook_theme_registry_alter().
   */
  public function themeRegistryAlter(array &$theme_registry) : void {
    // If Claro is the admin theme but not the active theme, use Claro's toolbar
    // templates.
    if ($this->isClaroAdminAndNotActive()) {
      // If the active theme is not Claro, but Claro is the admin theme, this
      // alters the registry so Claro's toolbar templates are used.
      foreach ([
        'toolbar',
        'menu__toolbar',
      ] as $registry_item) {
        if (isset($theme_registry[$registry_item])) {
          $theme_registry[$registry_item]['path'] = 'core/themes/claro/templates/navigation';
        }
      }
    }
  }
  
  /**
   * Determines if Claro is the admin theme but not the active theme.
   *
   * @return bool
   *   TRUE if Claro is the admin theme but not the active theme.
   */
  protected function isClaroAdminAndNotActive() {
    $admin_theme = $this->configFactory
      ->get('system.theme')
      ->get('admin');
    $active_theme = $this->themeManager
      ->getActiveTheme()
      ->getName();
    return $active_theme !== 'claro' && $admin_theme === 'claro';
  }

}