search_api_meilisearch-1.0.x-dev/modules/search_api_meilisearch_facets/src/EventSubscriber/ProcessingResultsSubscriber.php

<?php

namespace Drupal\search_api_meilisearch_facets\EventSubscriber;

use Drupal\search_api\Event\ProcessingResultsEvent;
use Drupal\search_api\Event\SearchApiEvents;
use Drupal\search_api_meilisearch\Api\MeilisearchApiServiceInterface;
use Drupal\search_api_meilisearch\Parser\FilterParserInterface;
use Drupal\search_api_meilisearch\Plugin\search_api\backend\SearchApiMeilisearchBackend;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

/**
 * Subscribes to processing results events.
 */
class ProcessingResultsSubscriber implements EventSubscriberInterface {

  /**
   * The MeiliSearch facets API service.
   *
   * @var \Drupal\search_api_meilisearch\Api\MeilisearchApiServiceInterface
   */
  protected MeilisearchApiServiceInterface $meiliService;

  /**
   * The filter parser.
   *
   * @var \Drupal\search_api_meilisearch\Parser\FilterParserInterface
   */
  protected FilterParserInterface $filterParser;

  /**
   * Constructs a new ProcessingResultsSubscriber object.
   */
  public function __construct(MeilisearchApiServiceInterface $meiliService, FilterParserInterface $filterParser) {
    $this->meiliService = $meiliService;
    $this->filterParser = $filterParser;
  }

  /**
   * For each facet, get results count.
   *
   * @param string $indexId
   *   The name of the index.
   * @param array $facets
   *   The facets to get results count for.
   * @param array $filters
   *   The filters to apply.
   * @param string $query
   *   The query to apply.
   *
   * @return array
   *   The facet results.
   *
   * @throws \Drupal\search_api_meilisearch\Api\MeiliSearchApiException
   * @throws \Drupal\Component\Plugin\Exception\InvalidPluginDefinitionException
   * @throws \Drupal\Component\Plugin\Exception\PluginNotFoundException
   */
  protected function getFacetData(string $indexId, array $facets, array $filters, string $query): array {
    $processFacets = [];
    foreach ($facets as $facet) {
      /*
       * @todo this is a hack to get all facets,
       * if meilisearch ever adds support for getting all facets remove this.
       */
      $allFacets = $this->meiliService->searchFacets($indexId, $facet);
      $allFacets = $allFacets->getFacetHits();
      $facetResult = $this->meiliService->searchFacets($indexId, $facet, NULL, $filters, $query);
      $facetResult = $facetResult->getFacetHits();
      $processFacets[$facet] = array_map(function ($facet) use ($facetResult) {
        // Check if the facet is in the facet result.
        $contains = array_filter($facetResult, function ($facetResult) use ($facet) {
          return $facetResult['value'] === $facet['value'];
        });
        return [
          'count' => empty($contains) ? 0 : reset($contains)['count'],
          'filter' => $facet['value'],
        ];
      }, $allFacets);
    }
    return $processFacets;
  }

  /**
   * Adds facets to the search results.
   *
   * @param \Drupal\search_api\Event\ProcessingResultsEvent $event
   *   The event.
   *
   * @throws \Drupal\Component\Plugin\Exception\InvalidPluginDefinitionException
   * @throws \Drupal\Component\Plugin\Exception\PluginNotFoundException
   * @throws \Drupal\search_api\SearchApiException
   * @throws \Drupal\search_api_meilisearch\Api\MeiliSearchApiException
   */
  public function onProcessingResults(ProcessingResultsEvent $event): void {
    $results = $event->getResults();
    $query = $results->getQuery();
    $backend = $query->getIndex()->getServerInstance()->getBackend();
    if ($backend instanceof SearchApiMeilisearchBackend) {
      $this->setConfiguration($backend);
      $keys = $query->getOriginalKeys() ?? '';
      $filters = $this->filterParser->parseExpression($query->getConditionGroup(), $query->getIndex());
      $facets = $query->getOption('search_api_facets', []);
      $facetResults = $this->getFacetData($query->getIndex()->id(), array_keys($facets), [$filters], $keys);
      $results->setExtraData('search_api_facets', $facetResults);
    }
  }

  /**
   * Set Meilisearch api connection configuration.
   *
   * @param \Drupal\search_api_meilisearch\Plugin\search_api\backend\SearchApiMeilisearchBackend $backend
   *   The backend.
   */
  protected function setConfiguration(SearchApiMeilisearchBackend $backend): void {
    $this->meiliService->setUrl($backend->getConfiguration()['meilisearch_host_address'] . ':' . $backend->getConfiguration()['meilisearch_host_port']);
    $this->meiliService->setMasterKey($backend->getConfiguration()['meilisearch_master_key']);
  }

  /**
   * {@inheritdoc}
   */
  public static function getSubscribedEvents(): array {
    return [
      SearchApiEvents::PROCESSING_RESULTS => 'onProcessingResults',
    ];
  }

}