class AjaxTestFocusFirstForm

class AjaxTestFocusFirstForm implements FormInterface {
    
    /**
     * {@inheritdoc}
     */
    public function getFormId() {
        return 'ajax_test_focus_first_command_form';
    }
    
    /**
     * {@inheritdoc}
     */
    public function buildForm(array $form, FormStateInterface $form_state) {
        $form['first_input'] = [
            '#type' => 'textfield',
        ];
        $form['second_input'] = [
            '#type' => 'textfield',
        ];
        $form['a_container'] = [
            '#type' => 'container',
            '#attributes' => [
                'id' => 'a-container',
            ],
        ];
        $form['a_container']['first_container_input'] = [
            '#type' => 'textfield',
        ];
        $form['a_container']['second_container_input'] = [
            '#type' => 'textfield',
        ];
        $form['focusable_container_without_tabbable_children'] = [
            '#type' => 'container',
            '#attributes' => [
                'tabindex' => '-1',
                'id' => 'focusable-container-without-tabbable-children',
            ],
            '#markup' => 'No tabbable children here',
        ];
        $form['multiple_of_same_selector_1'] = [
            '#type' => 'container',
            '#attributes' => [
                'id' => 'multiple-of-same-selector-1',
                'class' => [
                    'multiple-of-same-selector',
                ],
            ],
        ];
        $form['multiple_of_same_selector_1']['inside_same_selector_container_1'] = [
            '#type' => 'textfield',
        ];
        $form['multiple_of_same_selector_2'] = [
            '#type' => 'container',
            '#attributes' => [
                'id' => 'multiple-of-same-selector-2',
                'class' => [
                    'multiple-of-same-selector',
                ],
            ],
        ];
        $form['multiple_of_same_selector_2']['inside_same_selector_container_2'] = [
            '#type' => 'textfield',
        ];
        $form['nothing_tabbable'] = [
            '#type' => 'container',
            '#attributes' => [
                'id' => 'nothing-tabbable',
            ],
            '#markup' => 'nothing tabbable',
        ];
        $form['nothing_tabbable']['nested'] = [
            '#type' => 'container',
            '#markup' => 'There are divs in here, but nothing tabbable',
        ];
        $form['focus_first_in_container'] = [
            '#type' => 'submit',
            '#value' => 'Focus the first item in a container',
            '#name' => 'focusFirstContainer',
            '#ajax' => [
                'callback' => '::focusFirstInContainer',
            ],
        ];
        $form['focus_first_in_form'] = [
            '#type' => 'submit',
            '#value' => 'Focus the first item in the form',
            '#name' => 'focusFirstForm',
            '#ajax' => [
                'callback' => '::focusFirstInForm',
            ],
        ];
        $form['uses_selector_with_multiple_matches'] = [
            '#type' => 'submit',
            '#value' => 'Uses selector with multiple matches',
            '#name' => 'SelectorMultipleMatches',
            '#ajax' => [
                'callback' => '::focusFirstSelectorMultipleMatch',
            ],
        ];
        $form['focusable_container_no_tabbable_children'] = [
            '#type' => 'submit',
            '#value' => 'Focusable container, no tabbable children',
            '#name' => 'focusableContainerNotTabbableChildren',
            '#ajax' => [
                'callback' => '::focusableContainerNotTabbableChildren',
            ],
        ];
        $form['selector_has_nothing_tabbable'] = [
            '#type' => 'submit',
            '#value' => 'Try to focus container with nothing tabbable',
            '#name' => 'SelectorNothingTabbable',
            '#ajax' => [
                'callback' => '::selectorHasNothingTabbable',
            ],
        ];
        $form['selector_does_not_exist'] = [
            '#type' => 'submit',
            '#value' => 'Call FocusFirst on selector that does not exist.',
            '#name' => 'SelectorNotExist',
            '#ajax' => [
                'callback' => '::selectorDoesNotExist',
            ],
        ];
        $form['#attached']['library'][] = 'ajax_test/focus.first';
        return $form;
    }
    
    /**
     * Callback for testing FocusFirstCommand on a container.
     *
     * @return \Drupal\Core\Ajax\AjaxResponse
     *   The AJAX response.
     */
    public function selectorDoesNotExist() {
        $response = new AjaxResponse();
        return $response->addCommand(new FocusFirstCommand('#selector-does-not-exist'));
    }
    
    /**
     * Callback for testing FocusFirstCommand on a container.
     *
     * @return \Drupal\Core\Ajax\AjaxResponse
     *   The AJAX response.
     */
    public function selectorHasNothingTabbable() {
        $response = new AjaxResponse();
        return $response->addCommand(new FocusFirstCommand('#nothing-tabbable'));
    }
    
    /**
     * Callback for testing FocusFirstCommand on a container.
     *
     * @return \Drupal\Core\Ajax\AjaxResponse
     *   The AJAX response.
     */
    public function focusableContainerNotTabbableChildren() {
        $response = new AjaxResponse();
        return $response->addCommand(new FocusFirstCommand('#focusable-container-without-tabbable-children'));
    }
    
    /**
     * Callback for testing FocusFirstCommand on a container.
     *
     * @return \Drupal\Core\Ajax\AjaxResponse
     *   The AJAX response.
     */
    public function focusFirstSelectorMultipleMatch() {
        $response = new AjaxResponse();
        return $response->addCommand(new FocusFirstCommand('.multiple-of-same-selector'));
    }
    
    /**
     * Callback for testing FocusFirstCommand on a container.
     *
     * @return \Drupal\Core\Ajax\AjaxResponse
     *   The AJAX response.
     */
    public function focusFirstInContainer() {
        $response = new AjaxResponse();
        return $response->addCommand(new FocusFirstCommand('#a-container'));
    }
    
    /**
     * Callback for testing FocusFirstCommand on a form.
     *
     * @return \Drupal\Core\Ajax\AjaxResponse
     *   The AJAX response.
     */
    public function focusFirstInForm() {
        $response = new AjaxResponse();
        return $response->addCommand(new FocusFirstCommand('#ajax-test-focus-first-command-form'));
    }
    
    /**
     * {@inheritdoc}
     */
    public function validateForm(array &$form, FormStateInterface $form_state) {
    }
    
    /**
     * {@inheritdoc}
     */
    public function submitForm(array &$form, FormStateInterface $form_state) {
    }

}