class ActiveWorkspaceTestForm

class ActiveWorkspaceTestForm extends FormBase implements WorkspaceSafeFormInterface {
  
  /**
   * The workspace manager.
   */
  protected WorkspaceManagerInterface $workspaceManager;
  
  /**
   * The test key-value store.
   */
  protected KeyValueStoreInterface $keyValue;
  
  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container) : static {
    $instance = parent::create($container);
    $instance->workspaceManager = $container->get('workspaces.manager');
    $instance->keyValue = $container->get('keyvalue')
      ->get('ws_test');
    return $instance;
  }
  
  /**
   * {@inheritdoc}
   */
  public function getFormId() : string {
    return 'active_workspace_test_form';
  }
  
  /**
   * {@inheritdoc}
   */
  public function buildForm(array $form, FormStateInterface $form_state) : array {
    $form['test'] = [
      '#type' => 'textfield',
      '#ajax' => [
        'url' => Url::fromRoute('workspaces_test.get_form'),
        'callback' => function () {
          $this->keyValue
            ->set('ajax_test_active_workspace', $this->workspaceManager
            ->getActiveWorkspace()
            ->id());
          return new AjaxResponse();
        },
      ],
    ];
    return $form;
  }
  
  /**
   * {@inheritdoc}
   */
  public function submitForm(array &$form, FormStateInterface $form_state) : void {
    $this->keyValue
      ->set('form_test_active_workspace', $this->workspaceManager
      ->getActiveWorkspace()
      ->id());
  }

}