import { Injectable } from '@angular/core';
import { environment } from 'environments/environment';
import { interval, merge, fromEvent, Observable} from 'rxjs';
import { takeUntil, repeat, map} from 'rxjs/operators';

/**
 *  Idle timeout service used to track idle user
 */
@Injectable({
    providedIn: 'root'
})
export class IdleTimeoutService {

    // max timeout for an idle user
    readonly timeoutDelay = environment.session.timeout.idleTimeout || 300000; // 5 minutes

    // observable timeout
    readonly $onSessionTimeout: Observable<void>;

    constructor() {
        const events = ['mousemove', 'keydown', 'wheel', 'mousedown', 'scroll'];
        const $signal = merge(...events.map(eventName => fromEvent(document, eventName)));
        this.$onSessionTimeout = interval(this.timeoutDelay).pipe(
            takeUntil($signal),
            map(() => undefined),
            repeat()
        );
    }
}