Chris@0: <?php
Chris@0: 
Chris@0: namespace Drupal\taxonomy;
Chris@0: 
Chris@0: use Drupal\Core\Breadcrumb\BreadcrumbBuilderInterface;
Chris@0: use Drupal\Core\Breadcrumb\Breadcrumb;
Chris@0: use Drupal\Core\Entity\EntityManagerInterface;
Chris@0: use Drupal\Core\Link;
Chris@0: use Drupal\Core\Routing\RouteMatchInterface;
Chris@0: use Drupal\Core\StringTranslation\StringTranslationTrait;
Chris@0: 
Chris@0: /**
Chris@0:  * Provides a custom taxonomy breadcrumb builder that uses the term hierarchy.
Chris@0:  */
Chris@0: class TermBreadcrumbBuilder implements BreadcrumbBuilderInterface {
Chris@0:   use StringTranslationTrait;
Chris@0: 
Chris@0:   /**
Chris@0:    * The entity manager.
Chris@0:    *
Chris@0:    * @var \Drupal\Core\Entity\EntityManagerInterface
Chris@0:    */
Chris@0:   protected $entityManager;
Chris@0: 
Chris@0:   /**
Chris@0:    * The taxonomy storage.
Chris@0:    *
Chris@0:    * @var \Drupal\Taxonomy\TermStorageInterface
Chris@0:    */
Chris@0:   protected $termStorage;
Chris@0: 
Chris@0:   /**
Chris@0:    * Constructs the TermBreadcrumbBuilder.
Chris@0:    *
Chris@0:    * @param \Drupal\Core\Entity\EntityManagerInterface $entityManager
Chris@0:    *   The entity manager.
Chris@0:    */
Chris@0:   public function __construct(EntityManagerInterface $entityManager) {
Chris@0:     $this->entityManager = $entityManager;
Chris@0:     $this->termStorage = $entityManager->getStorage('taxonomy_term');
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function applies(RouteMatchInterface $route_match) {
Chris@0:     return $route_match->getRouteName() == 'entity.taxonomy_term.canonical'
Chris@0:       && $route_match->getParameter('taxonomy_term') instanceof TermInterface;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * {@inheritdoc}
Chris@0:    */
Chris@0:   public function build(RouteMatchInterface $route_match) {
Chris@0:     $breadcrumb = new Breadcrumb();
Chris@0:     $breadcrumb->addLink(Link::createFromRoute($this->t('Home'), '<front>'));
Chris@0:     $term = $route_match->getParameter('taxonomy_term');
Chris@0:     // Breadcrumb needs to have terms cacheable metadata as a cacheable
Chris@0:     // dependency even though it is not shown in the breadcrumb because e.g. its
Chris@0:     // parent might have changed.
Chris@0:     $breadcrumb->addCacheableDependency($term);
Chris@0:     // @todo This overrides any other possible breadcrumb and is a pure
Chris@0:     //   hard-coded presumption. Make this behavior configurable per
Chris@0:     //   vocabulary or term.
Chris@0:     $parents = $this->termStorage->loadAllParents($term->id());
Chris@0:     // Remove current term being accessed.
Chris@0:     array_shift($parents);
Chris@0:     foreach (array_reverse($parents) as $term) {
Chris@0:       $term = $this->entityManager->getTranslationFromContext($term);
Chris@0:       $breadcrumb->addCacheableDependency($term);
Chris@0:       $breadcrumb->addLink(Link::createFromRoute($term->getName(), 'entity.taxonomy_term.canonical', ['taxonomy_term' => $term->id()]));
Chris@0:     }
Chris@0: 
Chris@0:     // This breadcrumb builder is based on a route parameter, and hence it
Chris@0:     // depends on the 'route' cache context.
Chris@0:     $breadcrumb->addCacheContexts(['route']);
Chris@0: 
Chris@0:     return $breadcrumb;
Chris@0:   }
Chris@0: 
Chris@0: }