sclass WebBotTester implements AutoCloseable {
  S botURL; // without the "/incremental"
  S cookie = "test_" + aGlobalID();
  int n; // number of messages grabbed
  Thread grabThread;
  volatile bool closed;
  LS allHtml = syncList();
  new L<Msg> msgs;
  double readTimeout = 120.0, sendTimeout = 20.0;

  sclass Msg {
    S html;
    bool fromUser;
    long timeReceived;
  }
  
  *(S botID) { botURL = "https://botcompany.de/" + psI(botID) + "/raw"; }
  
  public void close {
    set closed;
    cancelAndInterruptThread(grabThread);
  }
  
  selfType start() {
    if (grabThread == null)
      grabThread = startThread(r _grabLoop);
    this;
  }
  
  void _grabLoop {
    while (!closed) {
      S html = loadPageWithTimeout(botURL + "/incremental" + hquery(+cookie, a := n), readTimeout);
      allHtml.add(html);
      S comment = first(getHTMLComments(html));
      int n = parseFirstIntOrMinus1(comment);
      if (n >= 0) this.n = n;
      sleepSeconds(1);
    }
  }
  
  void sendMsg(S msg) {
    print(postPageWithTimeout(sendTimeout, botURL + "/msg", +cookie, +msg));
  }
}