class ParagraphsTypeForm

class ParagraphsTypeForm extends EntityForm {

  /**
   * The paragraphs behavior plugin manager service.
   *
   * @var \Drupal\paragraphs\ParagraphsBehaviorManager
   */
  protected $paragraphsBehaviorManager;

  /**
   * The entity being used by this form.
   *
   * @var \Drupal\paragraphs\ParagraphsTypeInterface
   */
  protected $entity;

  /**
   * Provides messenger service.
   *
   * @var \Drupal\Core\Messenger\Messenger
   */
  protected $messenger;

  /**
   * GeneralSettingsForm constructor.
   *
   * @param \Drupal\paragraphs\ParagraphsBehaviorManager $paragraphs_behavior_manager
   *   The paragraphs type feature manager service.
   * @param \Drupal\Core\Messenger\MessengerInterface $messenger
   *   The messenger service.
   */
  public function __construct(ParagraphsBehaviorManager $paragraphs_behavior_manager, MessengerInterface $messenger) {
    $this->paragraphsBehaviorManager = $paragraphs_behavior_manager;
    $this->messenger = $messenger;
  }

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container) {
    return new static($container
      ->get('plugin.manager.paragraphs.behavior'), $container
      ->get('messenger'));
  }

  /**
   * {@inheritdoc}
   */
  public function form(array $form, FormStateInterface $form_state) {
    $form = parent::form($form, $form_state);
    $paragraphs_type = $this->entity;
    if (!$paragraphs_type
      ->isNew()) {
      $form['#title'] = $this
        ->t('Edit %title paragraph type', [
        '%title' => $paragraphs_type
          ->label(),
      ]);
    }
    $form['label'] = array(
      '#type' => 'textfield',
      '#title' => $this
        ->t('Label'),
      '#maxlength' => 255,
      '#default_value' => $paragraphs_type
        ->label(),
      '#description' => $this
        ->t("Label for the Paragraphs type."),
      '#required' => TRUE,
    );
    $form['id'] = array(
      '#type' => 'machine_name',
      '#default_value' => $paragraphs_type
        ->id(),
      '#machine_name' => array(
        'exists' => 'paragraphs_type_load',
      ),
      '#maxlength' => 32,
      '#disabled' => !$paragraphs_type
        ->isNew(),
    );
    $form['icon_file'] = [
      '#title' => $this
        ->t('Paragraph type icon'),
      '#type' => 'managed_file',
      '#upload_location' => ParagraphsTypeInterface::ICON_UPLOAD_LOCATION,
      '#upload_validators' => [
        'file_validate_extensions' => [
          'png jpg svg',
        ],
      ],
    ];
    if ($file = $this->entity
      ->getIconFile()) {
      $form['icon_file']['#default_value'] = [
        'target_id' => $file
          ->id(),
      ];
    }
    $form['description'] = [
      '#title' => $this
        ->t('Description'),
      '#type' => 'textarea',
      '#default_value' => $paragraphs_type
        ->getDescription(),
      '#description' => $this
        ->t('This text will be displayed on the <em>Add new paragraph</em> page.'),
    ];

    // Loop over the plugins that can be applied to this paragraph type.
    if ($behavior_plugin_definitions = $this->paragraphsBehaviorManager
      ->getApplicableDefinitions($paragraphs_type)) {
      $form['message'] = [
        '#type' => 'container',
        '#markup' => $this
          ->t('Behavior plugins are only supported by the stable paragraphs widget.', [], [
          'context' => 'paragraphs',
        ]),
        '#attributes' => [
          'class' => [
            'messages',
            'messages--warning',
          ],
        ],
      ];
      $form['behavior_plugins'] = [
        '#type' => 'details',
        '#title' => $this
          ->t('Behaviors', [], [
          'context' => 'paragraphs',
        ]),
        '#tree' => TRUE,
        '#open' => TRUE,
      ];
      $config = $paragraphs_type
        ->get('behavior_plugins');

      // Alphabetically sort plugins by plugin label.
      uasort($behavior_plugin_definitions, function ($a, $b) {
        return strcmp($a['label'], $b['label']);
      });
      foreach ($behavior_plugin_definitions as $id => $behavior_plugin_definition) {
        $description = $behavior_plugin_definition['description'];
        $form['behavior_plugins'][$id]['enabled'] = [
          '#type' => 'checkbox',
          '#title' => $behavior_plugin_definition['label'],
          '#title_display' => 'after',
          '#description' => $description,
          '#default_value' => !empty($config[$id]['enabled']),
        ];
        $form['behavior_plugins'][$id]['settings'] = [];
        $subform_state = SubformState::createForSubform($form['behavior_plugins'][$id]['settings'], $form, $form_state);
        $behavior_plugin = $paragraphs_type
          ->getBehaviorPlugin($id);
        if ($settings = $behavior_plugin
          ->buildConfigurationForm($form['behavior_plugins'][$id]['settings'], $subform_state)) {
          $form['behavior_plugins'][$id]['settings'] = $settings + [
            '#type' => 'fieldset',
            '#title' => $behavior_plugin_definition['label'],
            '#states' => [
              'visible' => [
                ':input[name="behavior_plugins[' . $id . '][enabled]"]' => [
                  'checked' => TRUE,
                ],
              ],
            ],
          ];
        }
      }
    }
    return $form;
  }

  /**
   * {@inheritdoc}
   */
  public function validateForm(array &$form, FormStateInterface $form_state) {
    parent::validateForm($form, $form_state);
    $paragraphs_type = $this->entity;
    $icon_file = $form_state
      ->getValue([
      'icon_file',
      '0',
    ]);

    // Set the icon file UUID and default value to the paragraph configuration.
    if (!empty($icon_file) && ($file = $this->entityTypeManager
      ->getStorage('file')
      ->load($icon_file))) {
      $paragraphs_type
        ->set('icon_uuid', $file
        ->uuid());
      $paragraphs_type
        ->set('icon_default', 'data:' . $file
        ->getMimeType() . ';base64,' . base64_encode(file_get_contents($file
        ->getFileUri())));
    }
    else {
      $paragraphs_type
        ->set('icon_uuid', NULL);
      $paragraphs_type
        ->set('icon_default', NULL);
    }
    if ($behavior_plugin_definitions = $this->paragraphsBehaviorManager
      ->getApplicableDefinitions($paragraphs_type)) {
      foreach ($behavior_plugin_definitions as $id => $behavior_plugin_definition) {

        // Only validate if the plugin is enabled and has settings.
        if (isset($form['behavior_plugins'][$id]['settings']) && $form_state
          ->getValue([
          'behavior_plugins',
          $id,
          'enabled',
        ])) {
          $subform_state = SubformState::createForSubform($form['behavior_plugins'][$id]['settings'], $form, $form_state);
          $behavior_plugin = $paragraphs_type
            ->getBehaviorPlugin($id);
          $behavior_plugin
            ->validateConfigurationForm($form['behavior_plugins'][$id]['settings'], $subform_state);
        }
      }
    }
  }

  /**
   * {@inheritdoc}
   */
  public function save(array $form, FormStateInterface $form_state) {
    $paragraphs_type = $this->entity;
    if ($behavior_plugin_definitions = $this->paragraphsBehaviorManager
      ->getApplicableDefinitions($paragraphs_type)) {
      foreach ($behavior_plugin_definitions as $id => $behavior_plugin_definition) {
        $behavior_plugin = $paragraphs_type
          ->getBehaviorPlugin($id);

        // If the behavior is enabled, initialize the configuration with the
        // enabled key and then let it process the form input.
        if ($form_state
          ->getValue([
          'behavior_plugins',
          $id,
          'enabled',
        ])) {
          $behavior_plugin
            ->setConfiguration([
            'enabled' => TRUE,
          ]);
          if (isset($form['behavior_plugins'][$id]['settings'])) {
            $subform_state = SubformState::createForSubform($form['behavior_plugins'][$id]['settings'], $form, $form_state);
            $behavior_plugin
              ->submitConfigurationForm($form['behavior_plugins'][$id]['settings'], $subform_state);
          }
        }
        else {

          // The plugin is not enabled, remove it from the paragraphs type.
          $paragraphs_type
            ->getBehaviorPlugins()
            ->removeInstanceId($id);
        }
      }
    }
    $status = $paragraphs_type
      ->save();
    $this->messenger
      ->addMessage($this
      ->t('Saved the %label Paragraphs type.', array(
      '%label' => $paragraphs_type
        ->label(),
    )));
    if ($status == SAVED_NEW && $this->moduleHandler
      ->moduleExists('field_ui') && ($route_info = FieldUI::getOverviewRouteInfo('paragraph', $paragraphs_type
      ->id()))) {
      $form_state
        ->setRedirectUrl($route_info);
    }
    else {
      $form_state
        ->setRedirect('entity.paragraphs_type.collection');
    }
  }

  /**
   * {@inheritdoc}
   */
  protected function actions(array $form, FormStateInterface $form_state) {
    $form = parent::actions($form, $form_state);

    // We want to display the button only on add page.
    if ($this->entity
      ->isNew() && $this->moduleHandler
      ->moduleExists('field_ui')) {
      $form['submit']['#value'] = $this
        ->t('Save and manage fields');
    }
    return $form;
  }

}