Add type filter and facet counts to the search endpoint

The search JSON gains tab support: the new `filter` GET parameter
restricts results to one document type (product, news, download, story,
page, market); the response carries `filter` (active value or null) and
`facets.type` with per-type counts and active flags. Counts stay
complete while a filter is active (keepAllFacetsOnSelection), so tabs
never collapse - except on an empty filtered result, documented in spec
v1.12 clause 7.16.

The parameter is named `filter` because `type` is TYPO3's reserved
page-type parameter and crashes page resolution; like q and page it is
excluded from cHash validation. Facets come from EXT:solr's native
faceting, serialized generically by SearchJsonRenderer - a future
category facet only needs TypoScript.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

packages/vitec/Classes/UserFunc/SearchJsonRenderer.php

@@ -28,6 +28,9 @@ use TYPO3\CMS\Frontend\ContentObject\ContentObjectRenderer;
  *     "numFound":       total hits,
  *     "totalPages":     ceil(numFound / resultsPerPage),
  *     "results":        [ { "title", "url", "type", "teaser" } ],
+ *     "filter":         the active type filter or null,
+ *     "facets":         { "type": [ { "value", "count", "active" } ] } -
+ *                       counts stay complete while a filter is active,
  *     "suggestions":    spellcheck alternatives ("did you mean"), [] if none
  *   }
  *
@@ -35,6 +38,8 @@ use TYPO3\CMS\Frontend\ContentObject\ContentObjectRenderer;
  *   q     = search terms; without it the empty shape above is returned
  *           (numFound 0) so the frontend always sees the same structure
  *   page  = 1-based page number, optional
+ *   filter = restrict results to one type from the `type` vocabulary
+ *           (page|product|market|story|news|download); unknown values ignored
  * The EXT:solr namespace (tx_solr[q], tx_solr[page]) is accepted as a
  * fallback so classic solr URLs keep working.
  *
@@ -132,13 +137,21 @@ class SearchJsonRenderer
             // excluded from cHash - cached variants would collide (config.no_cache
             // is gone in TYPO3 v14, so the cache is disabled per request here).
             $request->getAttribute('frontend.cache.instruction')
-                ?->disableCache('vitec search: response varies by q/page query parameters');
+                ?->disableCache('vitec search: response varies by q/page/filter query parameters');
 
             $params = $request->getQueryParams();
             $solrNamespace = (array)($params['tx_solr'] ?? []);
             $query = trim((string)($params['q'] ?? $solrNamespace['q'] ?? ''));
             $page = max(1, (int)($params['page'] ?? $solrNamespace['page'] ?? 1));
 
+            // Optional type filter, friendly vocabulary (see TYPE_LABELS).
+            // Unknown values are ignored, never an error.
+            $activeType = trim((string)($params['filter'] ?? ''));
+            $typeFilterField = array_search($activeType, self::TYPE_LABELS, true);
+            if ($typeFilterField === false) {
+                $activeType = '';
+            }
+
             if ($query === '') {
                 return (string)json_encode($this->emptyResult());
             }
@@ -163,8 +176,12 @@ class SearchJsonRenderer
                 $typoScriptConfiguration,
                 $search,
             );
+            $arguments = ['q' => $query, 'page' => $page];
+            if ($activeType !== '') {
+                $arguments['filter'] = ['type:' . $typeFilterField];
+            }
             $searchRequest = GeneralUtility::makeInstance(SearchRequestBuilder::class, $typoScriptConfiguration)
-                ->buildForSearch(['q' => $query, 'page' => $page], $pageId, $languageId);
+                ->buildForSearch($arguments, $pageId, $languageId);
 
             $resultSet = $searchService->search($searchRequest);
 
@@ -205,6 +222,29 @@ class SearchJsonRenderer
                 // spellchecking disabled or unavailable - not essential
             }
 
+            $facets = [];
+            try {
+                foreach ($resultSet->getFacets() as $facet) {
+                    $options = [];
+                    foreach ($facet->getOptions() as $option) {
+                        $value = (string)$option->getUriValue();
+                        if ($facet->getName() === 'type') {
+                            $value = self::TYPE_LABELS[$value] ?? $value;
+                        }
+                        $options[] = [
+                            'value' => $value,
+                            'count' => $option->getDocumentCount(),
+                            'active' => $option->getSelected(),
+                        ];
+                    }
+                    if ($options !== []) {
+                        $facets[$facet->getName()] = $options;
+                    }
+                }
+            } catch (\Throwable) {
+                // faceting disabled or unavailable - facets stay empty
+            }
+
             $numFound = $resultSet->getAllResultCount();
             $resultsPerPage = $resultSet->getUsedResultsPerPage() ?: count($results);
 
@@ -214,6 +254,8 @@ class SearchJsonRenderer
                 'resultsPerPage' => $resultsPerPage,
                 'numFound' => $numFound,
                 'totalPages' => $resultsPerPage > 0 ? (int)ceil($numFound / $resultsPerPage) : 0,
+                'filter' => $activeType !== '' ? $activeType : null,
+                'facets' => (object)$facets,
                 'results' => $results,
                 'suggestions' => array_values(array_unique($suggestions)),
             ]);
@@ -233,6 +275,8 @@ class SearchJsonRenderer
             'resultsPerPage' => 0,
             'numFound' => 0,
             'totalPages' => 0,
+            'filter' => null,
+            'facets' => new \stdClass(),
             'results' => [],
             'suggestions' => [],
         ];