Auto-choose tokenizer

Closes #3477973

modules/ai_search/src/Backend/AiSearchBackendPluginBase.php

@@ -3,9 +3,11 @@
 namespace Drupal\ai_search\Backend;
 
 use Drupal\Core\Form\FormStateInterface;
+use Drupal\ai\Utility\TokenizerInterface;
 use Drupal\ai_search\Trait\AiSearchBackendEmbeddingsEngineTrait;
 use Drupal\ai_search\Trait\AiSearchBackendEmbeddingsStrategyTrait;
 use Drupal\search_api\Backend\BackendPluginBase;
+use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
  * Base class for Search API AI backend plugins.
@@ -21,6 +23,43 @@ abstract class AiSearchBackendPluginBase extends BackendPluginBase {
   use AiSearchBackendEmbeddingsEngineTrait;
   use AiSearchBackendEmbeddingsStrategyTrait;
 
+  /**
+   * Constructs an AiSearchBackendPluginBase object.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin_id for the plugin instance.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Drupal\ai\Utility\TokenizerInterface $tokenizer
+   *   The tokenizer.
+   */
+  public function __construct(
+    array $configuration,
+    string $plugin_id,
+    array $plugin_definition,
+    protected TokenizerInterface $tokenizer,
+  ) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    $tokenizer = $container->get('ai.tokenizer');
+    $plugin = new static($configuration, $plugin_id, $plugin_definition, $tokenizer);
+
+    /** @var \Drupal\Core\StringTranslation\TranslationInterface $translation */
+    $translation = $container->get('string_translation');
+    $plugin->setStringTranslation($translation);
+    $plugin->setFieldsHelper($container->get('search_api.fields_helper'));
+    $plugin->setMessenger($container->get('messenger'));
+    $plugin->tokenizer = $container->get('ai.tokenizer');
+    return $plugin;
+  }
+
   /**
    * {@inheritdoc}
    */
@@ -54,7 +93,7 @@ abstract class AiSearchBackendPluginBase extends BackendPluginBase {
 
     // Build the form for both types.
     return array_merge(
-      $this->engineConfigurationForm($form, $form_state),
+      $this->engineConfigurationForm($form, $form_state, $this->tokenizer),
       $this->strategyConfigurationForm($form, $form_state)
     );
   }