class MenuTestController

class MenuTestController extends ControllerBase {
    
    /**
     * The theme manager.
     *
     * @var \Drupal\Core\Theme\ThemeManagerInterface
     */
    protected $themeManager;
    
    /**
     * The theme negotiator.
     *
     * @var \Drupal\Core\Theme\ThemeNegotiatorInterface
     */
    protected $themeNegotiator;
    
    /**
     * The active route match.
     *
     * @var \Drupal\Core\Routing\RouteMatchInterface
     */
    protected $routeMatch;
    
    /**
     * Constructs the MenuTestController object.
     *
     * @param \Drupal\menu_test\Controller\ThemeManagerInterface $theme_manager
     *   The theme manager.
     * @param \Drupal\menu_test\Controller\ThemeNegotiatorInterface $theme_negotiator
     *   The theme negotiator.
     * @param \Drupal\menu_test\Controller\RouteMatchInterface $route_match
     *   The current route match.
     */
    public function __construct(ThemeManagerInterface $theme_manager, ThemeNegotiatorInterface $theme_negotiator, RouteMatchInterface $route_match) {
        $this->themeManager = $theme_manager;
        $this->themeNegotiator = $theme_negotiator;
        $this->routeMatch = $route_match;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container) {
        return new static($container->get('theme.manager'), $container->get('theme.negotiator'), $container->get('current_route_match'));
    }
    
    /**
     * Some known placeholder content which can be used for testing.
     *
     * @return string
     *   A string that can be used for comparison.
     */
    public function menuTestCallback() {
        return [
            '#markup' => 'This is the menuTestCallback content.',
        ];
    }
    
    /**
     * A title callback method for test routes.
     *
     * @param array $_title_arguments
     *   Optional array from the route defaults.
     * @param string $_title
     *   Optional _title string from the route defaults.
     *
     * @return string
     *   The route title.
     */
    public function titleCallback(array $_title_arguments = [], $_title = '') {
        $_title_arguments += [
            'case_number' => '2',
            'title' => $_title,
        ];
        return t($_title_arguments['title']) . ' - Case ' . $_title_arguments['case_number'];
    }
    
    /**
     * Page callback: Tests the theme negotiation functionality.
     *
     * @param bool $inherited
     *   TRUE when the requested page is intended to inherit
     *   the theme of its parent.
     *
     * @return string
     *   A string describing the requested custom theme and actual
     *   theme being used
     *   for the current page request.
     */
    public function themePage($inherited) {
        $theme_key = $this->themeManager
            ->getActiveTheme()
            ->getName();
        // Now we check what the theme negotiator service returns.
        $active_theme = $this->themeNegotiator
            ->determineActiveTheme($this->routeMatch);
        $output = "Active theme: {$active_theme}. Actual theme: {$theme_key}.";
        if ($inherited) {
            $output .= ' Theme negotiation inheritance is being tested.';
        }
        return [
            '#markup' => $output,
        ];
    }
    
    /**
     * A title callback for XSS breadcrumb check.
     *
     * @return string
     */
    public function breadcrumbTitleCallback() {
        return '<script>alert(123);</script>';
    }

}