/// <reference types="node" />
import * as events from 'events';
import AppDatabase from './apps/database';
export declare enum ActivityMonitorStatus {
    Starting = "starting",
    Running = "running",
    Idle = "idle",
    Stopping = "stopping"
}
/**
 * Monitors engine activity and emits an 'idle' event when engine is inactive.
 * There are two monitoring timers. The first timer starts when there is no apps
 * and resets on any activity.  The second timer starts after the first timer
 * expires and immdiately broadcasts a ping message to all conversations. Any
 * activity from ping resoponse or other events will reset the timers.
 * The reason for the second timer is to avoid bounce from an idle but connected
 * client session, which reconnects when the connection is closed.
 */
export declare class ActivityMonitor extends events.EventEmitter {
    private _name;
    private _status;
    private _appdb;
    private _lastUpdate;
    private _idleTimeout;
    private _idleTimeoutMillis;
    private _quiesceTimeout;
    private _quiesceTimeoutMillis;
    private _appAddedListener;
    private _appRemovedListener;
    constructor(appdb: AppDatabase, options?: {
        idleTimeoutMillis?: number;
        quiesceTimeoutMillis?: number;
    });
    set name(name: string);
    get status(): ActivityMonitorStatus;
    start(): Promise<void>;
    updateActivity(): void;
    private _maybeStartActivityTimeout;
    private _startQuiesce;
    stop(): Promise<void>;
}