/**
 * @module Lock
 */
import { TimeSpan } from "../../../../utilities/_module-exports.js";
/**
 * @internal
 */
export type ILockState = {
    expiration: Date | null;
};
/**
 * @internal
 */
export type ILockStore = Partial<Record<string, ILockState>>;
/**
 * @internal
 */
export declare class LockState {
    private stateRecord;
    private readonly key;
    constructor(stateRecord: ILockStore, key: string);
    /**
     * Return the expiration as a date.
     */
    get(): Date | null;
    /**
     * Sets the expiration time.
     * If a number is provided, it must be in milliseconds.
     */
    set(ttl: TimeSpan | number | null): void;
    /**
     * Checks if the key is expired.
     */
    isExpired(): boolean;
    /**
     * Returns the remaining time.
     */
    getRemainingTime(): TimeSpan | null;
    /**
     * Removes the expiration from the record.
     */
    remove(): void;
}