// Copyright (C) 2018 Avatao.com Innovative Learning Kft.
// All Rights Reserved. See LICENSE file for details.

import { Injectable } from '@angular/core';
import { Observable } from 'rxjs';
import { webSocket, WebSocketSubject } from 'rxjs/webSocket';
import { filter, map } from 'rxjs/operators';
import { WebSocketMessage } from '../message-types/websocket-message';


@Injectable()
export class WebSocketService {
  private ws: WebSocketSubject<WebSocketMessage>;

  constructor() {}

  public connect() {
    if (!this.ws) {
      const wsproto = (location.protocol === 'https:') ? 'wss://' : 'ws://';
      const connAddr = wsproto + window.location.host + '/ws';
      this.ws = webSocket<WebSocketMessage>(connAddr);
    }
  }

  public observeKey<T extends WebSocketMessage>(key: string): Observable<T> {
    return this.ws.pipe(
      filter(message => message.key.startsWith(key)),
      map(message => <T> message)
    );
  }

  public sendJSON(json: any) {
    this.ws.next(json);
  }
}