Class RvfEmbeddingCache

v3/@claude-flow/embeddings/src/rvf-embedding-cache.ts:89–578

 * Uses an in-memory Map with periodic flush to a compact binary file.
 */
export class RvfEmbeddingCache {
  private readonly cachePath: string;
  private readonly maxSize: number;
  private readonly ttlMs: number;
  private readonly dimensions: number | undefined;

  private entries: Map<number, CacheEntry> = new Map();
  private textToHash: Map<string, number> = new Map();
  private dirty = false;
  private flushTimer: ReturnType<typeof setInterval> | null = null;
  private initialized = false;

  constructor(config: RvfEmbeddingCacheConfig) {
    this.cachePath = config.cachePath;
    this.maxSize = config.maxSize ?? DEFAULT_MAX_SIZE;
    this.ttlMs = config.ttlMs ?? DEFAULT_TTL_MS;
    this.dimensions = config.dimensions;
    validatePath(this.cachePath);
  }

  // --------------------------------------------------------------------------
  // Initialization
  // --------------------------------------------------------------------------

  /**
   * Lazily initialize the cache: load from disk if file exists, start auto-flush.
   */
  private async ensureInitialized(): Promise<void> {
    if (this.initialized) return;

    // Ensure parent directory exists
    const dir = dirname(this.cachePath);
    if (!existsSync(dir)) {
      mkdirSync(dir, { recursive: true });
    }

    // Load existing cache file
    if (existsSync(this.cachePath)) {
      this.loadFromFile();
    }

    // Clean expired entries on startup
    this.cleanExpired();

    // Start auto-flush timer
    this.startAutoFlush();

    this.initialized = true;
  }

  // --------------------------------------------------------------------------
  // Public API (matches PersistentEmbeddingCache)
  // --------------------------------------------------------------------------

  /**
   * Get an embedding from the cache by text.
   * Returns null if not found or expired.
   */