og-8.x-1.x-dev/src/Plugin/Field/FieldType/OgStandardReferenceItem.php

<?php

declare(strict_types=1);

namespace Drupal\og\Plugin\Field\FieldType;

use Drupal\Component\Utility\Html;
use Drupal\Core\Entity\EntityReferenceSelection\SelectionPluginManagerInterface;
use Drupal\Core\Field\Attribute\FieldType;
use Drupal\Core\Field\Plugin\Field\FieldType\EntityReferenceItem;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\StringTranslation\TranslatableMarkup;
use Drupal\Core\TypedData\ComplexDataDefinitionInterface;
use Drupal\Core\TypedData\TypedDataInterface;
use Drupal\og\Plugin\Field\OgEntityReferenceFieldItemList;

/**
 * Field item class for OG membership references.
 */
#[FieldType(
  id: 'og_standard_reference',
  label: new TranslatableMarkup('OG reference'),
  description: new TranslatableMarkup('An entity reference field pointing to the OG group entity, for a non-user entity.'),
  category: 'reference',
  default_widget: 'options_select',
  default_formatter: 'entity_reference_label',
  no_ui: TRUE,
  list_class: OgEntityReferenceFieldItemList::class,
)]
class OgStandardReferenceItem extends EntityReferenceItem {

  /**
   * Selection plugin manager.
   */
  protected SelectionPluginManagerInterface $selectionPluginManager;

  public function __construct(
    ComplexDataDefinitionInterface $definition,
    $name,
    ?TypedDataInterface $parent,
    ?SelectionPluginManagerInterface $selectionPluginManager = NULL,
  ) {
    parent::__construct($definition, $name, $parent);

    // If the field item is instantiated without DI (e.g. by TypedData),
    // resolve the selection‑plugin manager from the container so the item
    // still works.
    $this->selectionPluginManager = $selectionPluginManager
      ?? \Drupal::service('plugin.manager.entity_reference_selection');
  }

  /**
   * {@inheritdoc}
   */
  public function fieldSettingsForm(array $form, FormStateInterface $form_state) {
    $field = $form_state->getFormObject()->getEntity();

    // Get all selection plugins for this entity type.
    $selection_plugins = $this->selectionPluginManager->getSelectionGroups($this->getSetting('target_type'));
    $handlers_options = [];
    foreach (array_keys($selection_plugins) as $selection_group_id) {

      if ($selection_group_id == 'og') {
        // Handle the og selection group.
        $selection_group_plugin = 'og:default';
        $handlers_options[$selection_group_plugin] = Html::escape((string) $selection_plugins[$selection_group_id][$selection_group_plugin]['label']);
      }
    }

    $form = [
      '#type' => 'container',
      '#process' => [[static::class, 'fieldSettingsAjaxProcess']],
      '#element_validate' => [[static::class, 'fieldSettingsFormValidate']],

    ];
    $form['handler'] = [
      '#type' => 'details',
      '#title' => $this->t('Reference type'),
      '#open' => TRUE,
      '#tree' => TRUE,
      '#process' => [[static::class, 'formProcessMergeParent']],
    ];

    $form['handler']['handler'] = [
      '#type' => 'select',
      '#title' => $this->t('Reference method'),
      '#options' => $handlers_options,
      '#default_value' => $field->getSetting('handler'),
      '#required' => TRUE,
      // Use a form process callback to build #ajax property properly and also
      // to avoid code duplication.
      // @see \Drupal\Core\Field\Plugin\Field\FieldType\EntityReferenceItem::fieldSettingsAjaxProcess()
      '#ajax' => TRUE,
      '#limit_validation_errors' => [],
    ];
    $form['handler']['handler_submit'] = [
      '#type' => 'submit',
      '#name' => 'handler_settings_submit',
      '#value' => $this->t('Change handler'),
      '#limit_validation_errors' => [],
      '#attributes' => [
        'class' => ['js-hide'],
      ],
      '#submit' => [[static::class, 'settingsAjaxSubmit']],
    ];

    $form['handler']['handler_settings'] = [
      '#type' => 'container',
      '#attributes' => ['class' => ['entity_reference-settings']],
    ];

    $field->setSetting('handler', 'og:default');
    $handler = $this->selectionPluginManager->getSelectionHandler($field);
    $form['handler']['handler_settings'] += $handler->buildConfigurationForm([], $form_state);

    return $form;
  }

}