Issue #3090101: Items marked not marked as 'Allow adding to library' can be added to library

Closes #3090101

modules/paragraphs_library/src/Form/LibraryItemSettingsForm.php

@@ -4,12 +4,55 @@ namespace Drupal\paragraphs_library\Form;
 
 use Drupal\Core\Form\ConfigFormBase;
 use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Entity\EntityFieldManagerInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Drupal\Core\Entity\EntityReferenceSelection\SelectionPluginManagerInterface;
 
 /**
  * Form for Paragraphs library item settings.
  */
 class LibraryItemSettingsForm extends ConfigFormBase {
 
+  /**
+   * The entity reference selection plugin manager.
+   *
+   * @var \Drupal\Core\Entity\EntityReferenceSelection\SelectionPluginManagerInterface
+   */
+  protected $pluginManagerEntityReferenceSelection;
+
+  /**
+   * The entity field manager.
+   *
+   * @var \Drupal\Core\Entity\EntityFieldManagerInterface
+   */
+  protected $entityFieldManager;
+
+  /**
+   * Constructs a new LibraryItemBaseParagraphOverrideForm object.
+   *
+   * @param \Drupal\Core\Entity\EntityReferenceSelection\SelectionPluginManagerInterface $plugin_manager_entity_reference_selection
+   *   The selection plugin manager.
+   * @param \Drupal\Core\Entity\EntityFieldManagerInterface $entity_field_manager
+   *   The entity field manager.
+   */
+  public function __construct(
+    SelectionPluginManagerInterface $plugin_manager_entity_reference_selection,
+    EntityFieldManagerInterface $entity_field_manager
+  ) {
+    $this->entityFieldManager = $entity_field_manager;
+    $this->pluginManagerEntityReferenceSelection = $plugin_manager_entity_reference_selection;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('plugin.manager.entity_reference_selection'),
+      $container->get('entity_field.manager')
+    );
+  }
+
   /**
    * {@inheritdoc}
    */
@@ -28,11 +71,64 @@ class LibraryItemSettingsForm extends ConfigFormBase {
    * {@inheritdoc}
    */
   public function buildForm(array $form, FormStateInterface $form_state) {
-    // This exists to make the field UI pages visible and must not be removed.
-    $form['account'] = array(
-      '#markup' => '<p>' . $this->t('There are no settings yet.') . '</p>',
-    );
+    $paragraph_selection_handler = $this->getParagraphSelectionHandler();
+
+    // Set the form state to match the existing paragraph selection handler
+    // settings.
+    $fields = $this->entityFieldManager->getFieldDefinitions('paragraphs_library_item', 'paragraphs_library_item');
+    $settings = $fields['paragraphs']->getConfig('paragraphs_library_item')->getSettings();
+    if (!empty($settings['handler_settings'])) {
+      // Since we are building a handler's form, have to move handler settings
+      // up to the same level as the rest of the config.
+      $handler_settings = $settings['handler_settings'];
+      unset($settings['handler_settings']);
+      $settings = array_merge($settings, $handler_settings);
+      $paragraph_selection_handler->setConfiguration($settings);
+    }
+
+    // Build this form using the ParagraphsSelection form.
+    $form = $paragraph_selection_handler->buildConfigurationForm($form, $form_state);
 
     return parent::buildForm($form, $form_state);
   }
+
+  /**
+   * Get an instance of the paragraph selection handler.
+   *
+   * @return false|\Drupal\paragraphs\Plugin\EntityReferenceSelection\ParagraphSelection
+   *   The paragraph selection handler.
+   */
+  protected function getParagraphSelectionHandler() {
+    // Get an instance of the ParagraphsSelection handler.
+    $options = [
+      'target_type' => 'paragraph',
+      'handler' => 'default:paragraph',
+    ];
+    return $this->pluginManagerEntityReferenceSelection->getInstance($options);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+
+    // Get only the values related to the paragraph selection handler form.
+    $values = $form_state->getValues();
+    $paragraph_selection_handler = $this->getParagraphSelectionHandler();
+    $paragraph_selection_form = $paragraph_selection_handler->buildConfigurationForm([], $form_state);
+    $paragraph_selection_form_values = array_intersect_key($values, $paragraph_selection_form);
+
+    // Get existing paragraphs selection settings.
+    $fields = $this->entityFieldManager->getFieldDefinitions('paragraphs_library_item', 'paragraphs_library_item');
+    $paragraphs_config = $fields['paragraphs']->getConfig('paragraphs_library_item');
+    $settings = $paragraphs_config->getSettings();
+
+    // Save the new handler settings.
+    $settings['handler_settings'] = $paragraph_selection_form_values;
+    $settings['handler'] = 'default:paragraph';
+    $paragraphs_config->setSettings($settings)->save();
+
+    $this->entityFieldManager->clearCachedFieldDefinitions();
+  }
+
 }