refactor(theme-search-algolia): migrate package to TS (#5935)

packages/docusaurus-theme-common/src/index.ts

@@ -22,6 +22,8 @@ export {createStorageSlot, listStorageKeys} from './utils/storageUtils';
 
 export {useAlternatePageUtils} from './utils/useAlternatePageUtils';
 
+export {useContextualSearchFilters} from './utils/useContextualSearchFilters';
+
 export {
   parseCodeBlockTitle,
   parseLanguage,

packages/docusaurus-theme-common/src/utils/useContextualSearchFilters.ts

@@ -0,0 +1,49 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+import {useAllDocsData, useActivePluginAndVersion} from '@theme/hooks/useDocs';
+import {useDocsPreferredVersionByPluginId} from './docsPreferredVersion/useDocsPreferredVersion';
+import {docVersionSearchTag, DEFAULT_SEARCH_TAG} from './searchUtils';
+import useDocusaurusContext from '@docusaurus/useDocusaurusContext';
+
+export type useContextualSearchFiltersReturns = {
+  locale: string;
+  tags: string[];
+};
+
+// We may want to support multiple search engines, don't couple that to Algolia/DocSearch
+// Maybe users will want to use its own search engine solution
+export function useContextualSearchFilters(): useContextualSearchFiltersReturns {
+  const {i18n} = useDocusaurusContext();
+  const allDocsData = useAllDocsData();
+  const activePluginAndVersion = useActivePluginAndVersion();
+  const docsPreferredVersionByPluginId = useDocsPreferredVersionByPluginId();
+
+  function getDocPluginTags(pluginId: string) {
+    const activeVersion =
+      activePluginAndVersion?.activePlugin?.pluginId === pluginId
+        ? activePluginAndVersion.activeVersion
+        : undefined;
+
+    const preferredVersion = docsPreferredVersionByPluginId[pluginId];
+
+    const latestVersion = allDocsData[pluginId].versions.find((v) => v.isLast)!;
+
+    const version = activeVersion ?? preferredVersion ?? latestVersion;
+
+    return docVersionSearchTag(pluginId, version.name);
+  }
+
+  const tags = [
+    DEFAULT_SEARCH_TAG,
+    ...Object.keys(allDocsData).map(getDocPluginTags),
+  ];
+
+  return {
+    locale: i18n.currentLocale,
+    tags,
+  };
+}