class WorkspacesUiHooks

class WorkspacesUiHooks {
    
    /**
     * Implements hook_help().
     */
    public function help($route_name, RouteMatchInterface $route_match) : ?string {
        switch ($route_name) {
            // Main module help for the Workspaces UI module.
            case 'help.page.workspaces_ui':
                $output = '';
                $output .= '<h2>' . t('About') . '</h2>';
                $output .= '<p>' . t('The Workspaces UI module provides an interface for managing workspaces for the <a href=":workspaces_module">Workspaces module</a>. For more information, see the <a href=":workspaces">online documentation for the Workspaces UI module</a>.', [
                    ':workspaces_module' => Url::fromRoute('help.page', [
                        'name' => 'workspaces',
                    ])->toString(),
                    ':workspaces' => 'https://www.drupal.org/docs/8/core/modules/workspace/overview',
                ]) . '</p>';
                return $output;
        }
        return NULL;
    }
    
    /**
     * Implements hook_toolbar().
     */
    public function toolbar() : array {
        $items['workspace'] = [
            '#cache' => [
                'contexts' => [
                    'user.permissions',
                ],
            ],
        ];
        $current_user = \Drupal::currentUser();
        if (!$current_user->hasPermission('administer workspaces') && !$current_user->hasPermission('view own workspace') && !$current_user->hasPermission('view any workspace')) {
            return $items;
        }
        
        /** @var \Drupal\workspaces\WorkspaceInterface $active_workspace */
        $active_workspace = \Drupal::service('workspaces.manager')->getActiveWorkspace();
        $items['workspace'] += [
            '#type' => 'toolbar_item',
            'tab' => [
                '#lazy_builder' => [
                    'workspaces.lazy_builders:renderToolbarTab',
                    [],
                ],
                '#create_placeholder' => TRUE,
                '#lazy_builder_preview' => [
                    '#type' => 'link',
                    '#title' => $active_workspace ? $active_workspace->label() : t('Live'),
                    '#url' => Url::fromRoute('entity.workspace.collection'),
                    '#attributes' => [
                        'class' => [
                            'toolbar-tray-lazy-placeholder-link',
                        ],
                    ],
                ],
            ],
            '#wrapper_attributes' => [
                'class' => [
                    'workspaces-toolbar-tab',
                ],
            ],
            '#weight' => 500,
        ];
        // Add a special class to the wrapper if we don't have an active workspace so
        // we can highlight it with a different color.
        if (!$active_workspace) {
            $items['workspace']['#wrapper_attributes']['class'][] = 'workspaces-toolbar-tab--is-default';
        }
        // \Drupal\toolbar\Element\ToolbarItem::preRenderToolbarItem adds an
        // #attributes property to each toolbar item's tab child automatically.
        // Lazy builders don't support an #attributes property so we need to
        // add another render callback to remove the #attributes property. We start by
        // adding the defaults, and then we append our own pre render callback.
        $items['workspace'] += \Drupal::service('plugin.manager.element_info')->getInfo('toolbar_item');
        $items['workspace']['#pre_render'][] = 'workspaces.lazy_builders:removeTabAttributes';
        return $items;
    }

}