LanguageSwitcherLinksAlterer.php in Facets 8

Namespace

Drupal\facets

File

src/LanguageSwitcherLinksAlterer.php

<?php

namespace Drupal\facets;

use Drupal\Core\Cache\Cache;
use Drupal\Core\Cache\CacheBackendInterface;
use Drupal\Core\Entity\EntityTypeManagerInterface;
use Drupal\Core\Language\LanguageInterface;
use Drupal\Core\Language\LanguageManagerInterface;
use Drupal\Core\Url;
use Drupal\facets\UrlProcessor\UrlProcessorPluginManager;

/**
 * Helper service that alters the language switcher links.
 *
 * Facet URL aliases can be translated so we need to make sure that if we are
 * on a page that has facet filters in the URL, we replace the language switcher
 * links filters with the translated facet URL aliases for the target language.
 */
class LanguageSwitcherLinksAlterer {

  /**
   * The language manager.
   *
   * @var \Drupal\Core\Language\LanguageManagerInterface
   */
  protected $languageManager;

  /**
   * The cache backend.
   *
   * @var \Drupal\Core\Cache\CacheBackendInterface
   */
  protected $cacheBackend;

  /**
   * The entity type manager.
   *
   * @var \Drupal\Core\Entity\EntityTypeManagerInterface
   */
  protected $entityTypeManager;

  /**
   * The URL processor plugin manager.
   *
   * @var \Drupal\facets\UrlProcessor\UrlProcessorPluginManager
   */
  protected $urlProcessorManager;

  /**
   * The data needed to alter the language switcher links.
   *
   * @var array
   */
  protected $data = [];

  /**
   * LanguageSwitcherLinksAlterer constructor.
   *
   * @param \Drupal\Core\Language\LanguageManagerInterface $languageManager
   *   The language manager.
   * @param \Drupal\Core\Cache\CacheBackendInterface $cacheBackend
   *   The cache backend.
   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entityTypeManager
   *   The entity type manager.
   * @param \Drupal\facets\UrlProcessor\UrlProcessorPluginManager $urlProcessorManager
   *   The URL processor plugin manager.
   */
  public function __construct(LanguageManagerInterface $languageManager, CacheBackendInterface $cacheBackend, EntityTypeManagerInterface $entityTypeManager, UrlProcessorPluginManager $urlProcessorManager) {
    $this->languageManager = $languageManager;
    $this->cacheBackend = $cacheBackend;
    $this->entityTypeManager = $entityTypeManager;
    $this->urlProcessorManager = $urlProcessorManager;
  }

  /**
   * Alters the language switcher links.
   *
   * @param array $links
   *   The links.
   * @param $type
   *   The language type.
   * @param \Drupal\Core\Url $url
   *   The URL the switch links will be relative to.
   *
   * @see facets_language_switch_links_alter()
   */
  public function alter(array &$links, $type, Url $url) {
    if (!$this->data) {
      $this
        ->initializeData();
    }
    $current_language = $this->languageManager
      ->getCurrentLanguage();
    foreach ($links as &$link) {
      if (empty($link['language']) || !$link['language'] instanceof LanguageInterface || $link['language']
        ->getId() === $current_language
        ->getId()) {
        continue;
      }
      foreach ($this->data as $facet_id => $facet_info) {
        $filter_key = $facet_info['filter_key'];
        $separator = $facet_info['separator'];
        $url_aliases = $facet_info['url_aliases'];
        $original_language = $url_aliases['original'];
        if (!isset($link['query'][$filter_key]) || !is_array($link['query'][$filter_key])) {
          continue;
        }
        $untranslated_alias = $url_aliases[$this->languageManager
          ->getCurrentLanguage()
          ->getId()];
        $translated_alias = $url_aliases[$link['language']
          ->getId()];

        // If we don't have a translated alias, that means we're trying to create
        // a link to the original language.
        if ($translated_alias === NULL) {
          $translated_alias = $url_aliases[$original_language];
        }

        // If we don't have an untranslated alias, we're trying to create a link
        // from the original language.
        if ($untranslated_alias === NULL) {
          $untranslated_alias = $url_aliases[$original_language];
        }
        foreach ($link['query'][$filter_key] as &$filters) {
          $filters = preg_replace('/(' . $untranslated_alias . "){$separator}/", $translated_alias . $separator, $filters);
        }
      }
    }
  }

  /**
   * Initializes the data needed for altering the language switcher links.
   *
   * It runs through all the facets on the site and all the languages and
   * creates a cache of the URL aliases for all the languages.
   */
  protected function initializeData() {
    $cache = $this->cacheBackend
      ->get('facets_language_switcher_links');
    if ($cache) {
      $this->data = $cache->data;
      return;
    }
    $data = [];

    /** @var \Drupal\facets\FacetInterface[] $facets */
    $facets = $this->entityTypeManager
      ->getStorage('facets_facet')
      ->loadMultipleOverrideFree();
    $cache_tags = [];
    foreach ($facets as $facet) {
      $cache_tags = Cache::mergeTags($cache_tags, $facet
        ->getCacheTags());

      /** @var \Drupal\facets\UrlProcessor\UrlProcessorInterface $urlProcessor */
      $id = $facet
        ->getFacetSourceConfig()
        ->getUrlProcessorName();
      $url_processor = $this->urlProcessorManager
        ->createInstance($id, [
        'facet' => $facet,
      ]);
      if (!isset($data[$facet
        ->id()])) {
        $data[$facet
          ->id()] = [
          'separator' => $url_processor
            ->getSeparator(),
          'filter_key' => $facet
            ->getFacetSourceConfig()
            ->getFilterKey(),
          'url_aliases' => [
            'original' => $facet
              ->language()
              ->getId(),
            $facet
              ->language()
              ->getId() => $facet
              ->getUrlAlias(),
          ],
        ];
      }
      foreach ($this->languageManager
        ->getLanguages() as $language) {
        if ($language
          ->getId() === $facet
          ->language()
          ->getId()) {

          // Skip the original facet language as it's covered above.
          continue;
        }
        $config_name = 'facets.facet.' . $facet
          ->id();
        $translated_alias = $this->languageManager
          ->getLanguageConfigOverride($language
          ->getId(), $config_name)
          ->get('url_alias');
        $data[$facet
          ->id()]['url_aliases'][$language
          ->getId()] = $translated_alias;
      }
    }
    $this->data = $data;
    $this->cacheBackend
      ->set('facets_language_switcher_links', $data, Cache::PERMANENT, $cache_tags);
  }

}

Classes

Name	Description
LanguageSwitcherLinksAlterer	Helper service that alters the language switcher links.