/// <reference types="node" />
import { TimeServiceState } from './states/time-service-states';
import { ICommandOptions } from './index';
import { EventEmitter } from 'events';
import { TimeState, ITiming, ITimingControl } from 'node-test-bed-adapter';
export interface TimeService {
    on(event: 'stateUpdated', listener: (state: TimeState) => void): this;
    on(event: 'time', listener: (time: ITiming) => void): this;
}
export declare class TimeService extends EventEmitter implements TimeService {
    private adapter;
    private log;
    /** Can be used in clearInterval to reset the timer */
    private _timeHandler?;
    /** Real-time when the scenario is started */
    private _realStartTime?;
    /** Real-time of last update */
    private _lastTrialTimeUpdate?;
    /**  The fictive date and time of the simulation / trial as the number of milliseconds
     * from the UNIX epoch, 1 January 1970 00:00:00.000 UTC. */
    private _trialTime?;
    /** Current speed of the simulation in number of times real-time */
    private _trialTimeSpeed;
    private _state;
    /** Interval to send messages to Kafka and browser clients (via Socket.io.). */
    private readonly interval;
    constructor(options: ICommandOptions);
    connect(): Promise<{}>;
    /** Allow external services to control transitions. */
    transition(msg: ITimingControl): void;
    private subscribe;
    private handleMessage;
    readonly state: TimeServiceState;
    trialTime: number | undefined;
    trialTimeSpeed: number;
    readonly lastUpdateTime: number | undefined;
    readonly realStartTime: number | undefined;
    /**
     * Computes the new Trial Time using the amount of time that has passed since the previous computation of TrialTime
     * and the TrialTimeSpeed. Updates the Trial Time accordingly.
     */
    progressTrialTime(): number;
    startScenario(): void;
    stopScenario(): void;
    sendTimeUpdate(): void;
    sendTimeMessage(timeMsg: ITiming): void;
    private startProducingTimeMessages;
    private stopProducingTimeMessages;
}