Drupal 10: Remove the nodes marked as "noindex" from search API results

<?php
 
namespace Drupal\MY_CUSTOM_MODULE\Plugin\search_api\processor;
 
use Drupal\node\NodeInterface;
use Drupal\search_api\IndexInterface;
use Drupal\search_api\Processor\ProcessorPluginBase;
 
/**
 * Class NodeExclude.
 *
 * @package Drupal\MY_CUSTOM_MODULE\Plugin\search_api\processor
 *
 * @SearchApiProcessor(
 *   id = "MY_CUSTOM_MODULE_node_exclude",
 *   label = @Translation("Node exclude"),
 *   description = @Translation("Exclude specific nodes. For example remove the
 *   nodes marked as noindex by metatag."), stages = {
 *     "alter_items" = 0
 *   }
 * )
 */
class NodeExclude extends ProcessorPluginBase {
 
  /**
   * {@inheritdoc}
   */
  public static function supportsIndex(IndexInterface $index) {
    foreach ($index->getDatasources() as $datasource) {
      if ($datasource->getEntityTypeId() === 'node') {
        return TRUE;
      }
    }
 
    return FALSE;
  }
 
  /**
   * {@inheritdoc}
   */
  public function alterIndexedItems(array &$items) {
    /** @var \Drupal\search_api\Item\ItemInterface $item */
    foreach ($items as $item_id => $item) {
      $object = $item->getOriginalObject()->getValue();
      $exclude = FALSE;
      if ($object instanceof NodeInterface) {
        // Review it because oldest version of the Metatag module used field_meta_tags instead of field_metatag.
        if ($object->hasField('field_metatag')
          && !$object->get('field_metatag')->isEmpty()) {
          $metaTags = $object->get('field_metatag')->getString();
          $metaTags = unserialize($metaTags);
          if (isset($metaTags['robots'])) {
            $robots = explode(', ', $metaTags['robots']);
            if (in_array('noindex', $robots)) {
              $exclude = TRUE;
            }
          }
        }
      }
 
      if ($exclude) {
        unset($items[$item_id]);
      }
    }
  }
 
}