oidc-1.0.0-alpha2/src/EventSubscriber/LinkExistingAccountSubscriber.php

<?php

namespace Drupal\oidc\EventSubscriber;

use Drupal\Core\Entity\EntityStorageInterface;
use Drupal\Core\Entity\EntityTypeManagerInterface;
use Drupal\oidc\ExistingAccountValidatorInterface;
use Drupal\oidc\Event\LinkExistingAccountEvent;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

/**
 * Event subscriber to link an existing account by email.
 */
class LinkExistingAccountSubscriber implements EventSubscriberInterface {

  /**
   * The user storage.
   *
   * @var \Drupal\Core\Entity\EntityStorageInterface
   */
  protected EntityStorageInterface $userStorage;

  /**
   * The existing account validator.
   *
   * @var \Drupal\oidc\ExistingAccountValidatorInterface
   */
  protected ExistingAccountValidatorInterface $existingAccountValidator;

  /**
   * Class constructor.
   *
   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
   *   The entity type manager.
   * @param \Drupal\oidc\ExistingAccountValidatorInterface $existing_account_validator
   *   The existing account validator service.
   *
   * @throws \Drupal\Component\Plugin\Exception\InvalidPluginDefinitionException
   * @throws \Drupal\Component\Plugin\Exception\PluginNotFoundException
   */
  public function __construct(EntityTypeManagerInterface $entity_type_manager, ExistingAccountValidatorInterface $existing_account_validator) {
    $this->userStorage = $entity_type_manager->getStorage('user');
    $this->existingAccountValidator = $existing_account_validator;
  }

  /**
   * {@inheritdoc}
   */
  public static function getSubscribedEvents() {
    $events[LinkExistingAccountEvent::class][] = ['linkAccountByEmail', 1000];

    return $events;
  }

  /**
   * Try to link an existing account by email.
   *
   * @param \Drupal\oidc\Event\LinkExistingAccountEvent $event
   *   The link existing account event.
   */
  public function linkAccountByEmail(LinkExistingAccountEvent $event) {
    $email = $event->getJsonWebTokens()->getEmail();

    if (!$email) {
      return;
    }

    /** @var \Drupal\user\UserInterface[] $users */
    $users = $this->userStorage->loadByProperties([
      'mail' => $email,
    ]);

    foreach ($users as $user) {
      if (!$this->existingAccountValidator->isValid($user)) {
        continue;
      }

      $event->setAccount($user);
      $event->stopPropagation();
      break;
    }
  }

}