Method #performIndexLookup

packages/graph/src/Steps.ts:2446–2515

* Perform the actual index lookup based on the hint.

(
    indexManager: NonNullable<GraphSource<any>["indexManager"]>,
    label: string,
    hint: IndexHint,
  )

   * Perform the actual index lookup based on the hint.
   */
  #performIndexLookup(
    indexManager: NonNullable<GraphSource<any>["indexManager"]>,
    label: string,
    hint: IndexHint,
  ): Set<ElementId> | undefined {
    switch (hint.type) {
      case "hash": {
        const hashIndex = indexManager.getHashIndex(label, hint.property);
        if (!hashIndex) return undefined;

        if (hint.operation === "equals") {
          return new Set(hashIndex.lookup(hint.value));
        } else if (hint.operation === "in") {
          return hashIndex.lookupMany(hint.value as readonly unknown[]);
        }
        return undefined;
      }

      case "btree": {
        const btreeIndex = indexManager.getBTreeIndex(label, hint.property);
        if (!btreeIndex) return undefined;

        const value = hint.value as number | string;

        switch (hint.operation) {
          case "equals":
            return btreeIndex.lookup(value);
          case "lessThan":
            return btreeIndex.lookupLessThan(value);
          case "lessThanOrEqual":
            return btreeIndex.lookupLessThanOrEqual(value);
          case "greaterThan":
            return btreeIndex.lookupGreaterThan(value);
          case "greaterThanOrEqual":
            return btreeIndex.lookupGreaterThanOrEqual(value);
          default:
            return undefined;
        }
      }

      case "fulltext": {
        const fulltextIndex = indexManager.getFullTextIndex(label, hint.property);
        if (!fulltextIndex) return undefined;

        const value = hint.value as string;
        let results: Set<ElementId>;

        switch (hint.operation) {
          case "startsWith":
            results = fulltextIndex.searchTermPrefix(value);
            break;
          case "contains":
            results = fulltextIndex.searchContains(value);
            break;
          case "search": {
            const searchResults = fulltextIndex.search(value);
            results = new Set(searchResults.map((r) => r.elementId));
            break;