WebSocketClient.js

import Observable from "../utils/Observable.js";
import { ConnectionOpenedEvent, ConnectionClosedEvent, ConnectionErrorEvent,
  DataEvent } from "./Events.js";
import GazeData from "../data/GazeData.js";

class WebSocketClient extends Observable {

  constructor() {
    super();
  }

  connect(url) {
    this.ws = new WebSocket(url);
    this.ws.onopen = onOpen.bind(this);
    this.ws.onclose = onClose.bind(this);
    this.ws.onerror = onError.bind(this);
    this.ws.onmessage = onMessage.bind(this);
  }

}

function onOpen() {
  let connectionEvent = new ConnectionOpenedEvent();
  this.notifyAll(connectionEvent);
}

function onClose() {
  let connectionEvent = new ConnectionClosedEvent();
  this.notifyAll(connectionEvent);
}

function onError() {
  let connectionEvent = new ConnectionErrorEvent();
  this.notifyAll(connectionEvent);
}

function onMessage(event) {
  let data = GazeData.fromDataString(event.data),
    dataEvent = new DataEvent(data);
  this.notifyAll(dataEvent);
}

export default WebSocketClient;