class MenuLinksetSettingsForm

class MenuLinksetSettingsForm extends ConfigFormBase {
    
    /**
     * Constructs a MenuLinksetSettingsForm object.
     *
     * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
     *   The factory for configuration objects.
     * @param \Drupal\Core\Config\TypedConfigManagerInterface $typedConfigManager
     *   The typed config manager.
     * @param \Drupal\Core\Routing\RouteBuilderInterface $routerBuilder
     *   The router builder service.
     */
    public function __construct(ConfigFactoryInterface $config_factory, TypedConfigManagerInterface $typedConfigManager, RouteBuilderInterface $routerBuilder) {
        parent::__construct($config_factory, $typedConfigManager);
    }
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container) {
        return new static($container->get('config.factory'), $container->get('config.typed'), $container->get('router.builder'));
    }
    
    /**
     * {@inheritdoc}
     */
    public function getFormId() {
        return 'menu_linkset_settings';
    }
    
    /**
     * {@inheritdoc}
     */
    protected function getEditableConfigNames() {
        return [
            'system.feature_flags',
        ];
    }
    
    /**
     * {@inheritdoc}
     */
    public function buildForm(array $form, FormStateInterface $form_state) {
        $form['linkset']['enable_endpoint'] = [
            '#type' => 'checkbox',
            '#title' => $this->t('Enable the menu linkset endpoint'),
            '#description' => $this->t('See the <a href="@docs-link">decoupled menus documentation</a> for more information.', [
                '@docs-link' => 'https://www.drupal.org/docs/develop/decoupled-drupal/decoupled-menus',
            ]),
            '#default_value' => $this->config('system.feature_flags')
                ->get('linkset_endpoint'),
        ];
        return parent::buildForm($form, $form_state);
    }
    
    /**
     * {@inheritdoc}
     */
    public function submitForm(array &$form, FormStateInterface $form_state) {
        $this->config('system.feature_flags')
            ->set('linkset_endpoint', $form_state->getValue('enable_endpoint'))
            ->save();
        parent::submitForm($form, $form_state);
    }

}