import type Database from 'better-sqlite3';
import type { Lock } from '../types.js';
export declare class LockRepository {
    private readonly db;
    constructor(db: Database.Database);
    /**
     * Try to acquire a lock for the given key and owner.
     * - If no lock exists, inserts a new one. Returns true.
     * - If a lock exists and has not expired, returns false.
     * - If a lock exists but has expired, replaces it. Returns true.
     */
    acquire(key: string, owner: string, ttlSeconds?: number): boolean;
    /**
     * Release the lock for the given key, but only if the owner matches.
     * Returns true if a lock was deleted, false otherwise.
     */
    release(key: string, owner: string): boolean;
    /**
     * Returns true if a non-expired lock exists for the given key.
     */
    isHeld(key: string): boolean;
    /**
     * Find a lock by key. Returns null if not found or expired.
     */
    findByKey(key: string): Lock | null;
    /**
     * Delete all expired locks. Returns the number deleted.
     */
    cleanExpired(): number;
}
//# sourceMappingURL=lock.d.ts.map