mancala/src/rtmt/rtmt_websocket.ts

import { decode, encode } from "./encode_decode_message";
import { Bytes, OnMessage, RTMT } from "./rtmt";
import { server } from "../service/http_service";

export class RTMTWS implements RTMT {
  private messageChannels: Map<String, OnMessage>;
  private ws: WebSocket;

  constructor() {
    this.messageChannels = new Map<String, OnMessage>();
  }

  initWebSocket(
    userKey: string,
    onopen: () => any,
    onClose: () => any,
    onError: (event: Event) => any
  ) {
    const url = server.wsServerAdress + "?userKey=" + userKey;
    const ws = new WebSocket(url);
    ws.binaryType = "arraybuffer"; //for firefox
    ws.onopen = () => {
      console.info("(RTMT) ws has opened");
      this.ws = ws;
      onopen();
    };
    ws.onclose = () => {
      console.info("(RTMT) ws has closed");
      //this.ws = undefined
      onClose();
    };

    ws.onmessage = (event: MessageEvent) => {
      this.onWebSocketMessage(this, event);
    };

    ws.addEventListener("error", (ev) => {
      console.error({ ws_error: ev });
      onError(ev);
    });
  }

  sendMessage(channel: string, message: Object) {
    if (this.ws === undefined) {
      console.error("(RTMT) ws is undefined");
      return;
    }
    const data = encode(channel, message);
    this.ws.send(data);
  }

  listenMessage(channel: string, callback: OnMessage) {
    this.messageChannels.set(channel, callback);
  }

  onWebSocketMessage(rtmt: RTMTWS, event: MessageEvent) {
    const { channel, message } = decode(event.data);
    rtmt.onMessage(channel, message);
  }

  onMessage(channel: string, message: Bytes) {
    const callback = this.messageChannels.get(channel);

    if (callback) {
      callback(message);
    } else {
      console.warn("(RTMT) Channel callback not found!" + channel);
    }
  }
}