/**
 * @author   : Rajkeshwawr Prasad (rajkeshwar.pd@gmail.com) 
 * @date     : 2017-03-02 19:15:35 
 * @copyright: (c) 2016 Kanerika Software Pvt Ltd. 
 * @website  : http://kanerika.com/ 
 */

import { Subject } from 'rxjs/Subject';
import { Observable } from 'rxjs/Observable';
import 'rxjs/add/operator/filter';
import 'rxjs/add/operator/map';

//http://blog.lacolaco.net/post/event-broadcasting-in-angular-2/

interface BroadcastEvent {
  key: any;
  data?: any;
}

export class Broadcaster {
  private _eventBus: Subject<BroadcastEvent>;

  constructor() {
    this._eventBus = new Subject<BroadcastEvent>();
  }

  broadcast(key: any, data?: any) {
    this._eventBus.next({key, data});
  }

  on<T>(key: any): Observable<T> {
    return this._eventBus.asObservable()
      .filter(event => event.key === key)
      .map(event => <T>event.data);
  }
}