class SearchEmbeddedForm

class SearchEmbeddedForm extends FormBase {
    
    /**
     * {@inheritdoc}
     */
    public function getFormId() {
        return 'search_embedded_form';
    }
    
    /**
     * {@inheritdoc}
     */
    public function buildForm(array $form, FormStateInterface $form_state) {
        $count = \Drupal::state()->get('search_embedded_form.submit_count', 0);
        $form['name'] = [
            '#type' => 'textfield',
            '#title' => $this->t('Your name'),
            '#maxlength' => 255,
            '#default_value' => '',
            '#required' => TRUE,
            '#description' => $this->t('Times form has been submitted: %count', [
                '%count' => $count,
            ]),
        ];
        $form['actions'] = [
            '#type' => 'actions',
        ];
        $form['actions']['submit'] = [
            '#type' => 'submit',
            '#value' => $this->t('Send away'),
        ];
        return $form;
    }
    
    /**
     * {@inheritdoc}
     */
    public function submitForm(array &$form, FormStateInterface $form_state) {
        $state = \Drupal::state();
        $submit_count = $state->get('search_embedded_form.submit_count', 0);
        $state->set('search_embedded_form.submit_count', $submit_count + 1);
        $this->messenger()
            ->addStatus($this->t('Test form was submitted'));
    }

}