class EnabledConfigurablePluginsConstraintValidator

class EnabledConfigurablePluginsConstraintValidator extends ConstraintValidator implements ContainerInjectionInterface {
  use PluginManagerDependentValidatorTrait;
  use TextEditorObjectDependentValidatorTrait;
  
  /**
   * {@inheritdoc}
   *
   * @throws \Symfony\Component\Validator\Exception\UnexpectedTypeException
   *   Thrown when the given constraint is not supported by this validator.
   */
  public function validate($settings, Constraint $constraint) {
    if (!$constraint instanceof EnabledConfigurablePluginsConstraint) {
      throw new UnexpectedTypeException($constraint, __NAMESPACE__ . '\\EnabledConfigurablePluginsConstraint');
    }
    $configurable_enabled_definitions = $this->getConfigurableEnabledDefinitions();
    try {
      $plugin_settings = $this->context
        ->getRoot()
        ->get('settings.plugins')
        ->getValue();
    } catch (\InvalidArgumentException $e) {
      $plugin_settings = [];
    }
    foreach ($configurable_enabled_definitions as $id => $definition) {
      // Create a fresh instance of this CKEditor 5 plugin, not tied to a text
      // editor configuration entity.
      $plugin = $this->pluginManager
        ->getPlugin($id, NULL);
      // If this plugin is configurable but it has empty default configuration,
      // that means the configuration must be stored out of band.
      // @see \Drupal\ckeditor5\Plugin\CKEditor5Plugin\Image
      // @see editor_image_upload_settings_form()
      $default_configuration = $plugin->defaultConfiguration();
      if ($default_configuration === []) {
        continue;
      }
      if (!isset($plugin_settings[$id]) || empty($plugin_settings[$id])) {
        $this->context
          ->buildViolation($constraint->message)
          ->setParameter('%plugin_label', (string) $definition->label())
          ->setParameter('%plugin_id', $id)
          ->atPath("plugins.{$id}")
          ->addViolation();
      }
    }
  }
  
  /**
   * Gets all configurable CKEditor 5 plugin definitions that are enabled.
   *
   * @return \Drupal\ckeditor5\Plugin\CKEditor5PluginDefinition[]
   *   An array of enabled configurable CKEditor 5 plugin definitions.
   */
  private function getConfigurableEnabledDefinitions() : array {
    $text_editor = $this->createTextEditorObjectFromContext();
    $enabled_definitions = $this->pluginManager
      ->getEnabledDefinitions($text_editor);
    $configurable_enabled_definitions = array_filter($enabled_definitions, function (CKEditor5PluginDefinition $definition) : bool {
      return $definition->isConfigurable();
    });
    return $configurable_enabled_definitions;
  }

}