abstract sclass ThoughtBot {

}

static ThoughtBot thoughtBot;

static int longPollTick = 100;

static int longPollMaxWait = 1000*60;

sclass Msg {

  long time;

  bool fromUser;

  S text;

  L<S> buttons;

  *() {}

  *(bool *fromUser, S *text) { time = now(); }

}

concept Conversation {

  S cookie;

  new LL<Msg> oldDialogs;

  new L<Msg> msgs;

  void add(Msg m) {

    msgs.add(m);

    change();

  }

  int allCount() { ret lengthLevel2(oldDialogs) + l(msgs); }

  int archiveSize() { ret lengthLevel2(oldDialogs); }

}

svoid pWebChatBot {

  db();

}

static void sayAsync(S session, S text) {

  lock dbLock();

  Conversation conv = getConv(session);

  conv.add(new Msg(false, text));

  print("sayAsync " + session + ", new size=" + conv.allCount());

}

html {

 _registerThread();

 registerVisitor();

 fS cookie = cookieSent();

 try {

  Conversation conv;

  {

    lock dbLock();

    if (eq(uri, "/stats"))

      ret "Threads: " + ul_htmlEncode(getThreadNames(registeredThreads()));

    if (eq(uri, "/logs"))

      ret webChatBotLogsHTML();

    S message = trim(params.get("btn"));

    if (empty(message)) message = trim(params.get("message"));

    conv = getConv(cookie);

    if (match("clear", message)) {

      conv.oldDialogs.add(conv.msgs);

      cset(conv, msgs := new L);

      conv.change();

      thoughtBot.clearSession(conv.cookie);

      message = null;

    }

    thoughtBot.setSession(cookieSent());

    if (empty(conv.msgs))

      conv.add(new Msg(false, initialMessage()));

    if (nempty(message) && !lastUserMessageWas(conv, message))

      conv.add(new Msg(true, message));

    if (nempty(conv.msgs) && last(conv.msgs).fromUser) {

      S reply = "I'm sorry, I don't understand";

      L<S> buttons = null;

      pcall {

        reply = or2(makeReply(last(conv.msgs).text), reply);

        buttons = (L<S>) getThreadLocal(thoughtBot, "buttons");

      }

      Msg msg = new Msg(false, reply);

      msg.buttons = buttons;

      conv.add(msg);

    }

  } // locked

  if (eq(uri, "/msg")) ret "OK";

  if (eq(uri, "/incremental")) {

    int a = parseInt(params.get("a")), origA = a;

    //int b = parseInt(params.get("b"));

    int as = conv.archiveSize();

    a -= as;

    //b -= as;

    long start = sysNow();

    L msgs;

    bool first = true;

    while (licensed() && sysNow() < start+longPollMaxWait) {

      msgs = subList(conv.msgs, a);

      if (empty(msgs)) {

        if (first) {

          print("Long poll starting on " + cookie + ", " + origA + "/" + a);

          first = false;

        }

        sleep(longPollTick);

      } else {

        if (first) print("Long poll ended.");

        new StringBuilder buf;

        renderMessages(buf, msgs);

        ret "<!-- " + conv.allCount() + "-->\n"  + buf;

      }

    }

    ret "";

  }

  {

    lock dbLock();

    S html = loadSnippet(templateID); // TODO: cache

    new StringBuilder buf;

    renderMessages(buf, conv.msgs);

    html = html.replace("#N#", str(conv.allCount()));

    html = html.replace("#INCREMENTALURL#", relativeRawBotLink(programID(), "incremental?a=");

    html = html.replace("#MSGURL#", relativeRawBotLink(programID(), "msg?message="));

    if (nempty(params.get("debug")))

      html = html.replace("var showActions = false;", "var showActions = true;");

    html = html.replace("$HEADING", heading);

    html = html.replace("<!-- MSGS HERE -->", str(buf));

    html = hreplaceTitle(html, heading);

    html = hmobilefix(html);

    ret html;

  }

 } finally {

  _unregisterThread();

 }

}

svoid renderMessages(StringBuilder buf, L<Msg> msgs) {

  for (Msg m : msgs)

    if (m.fromUser || neq(m.text, "-"))

      appendMsg(buf, m.fromUser ? "Esteemed Customer" : botName, formatTime(m.time), htmlencode(m.text), !m.fromUser);

  L<S> buttons = last(msgs).buttons;

  if (nempty(buttons))

    appendButtons(buf, buttons);

}

svoid appendMsg(StringBuilder buf, S name, S time, S text, bool bot) {

  S imgLink = snippetImgLink(bot ? #1008323 : #1008359);

	buf.append([[<div class="direct-chat-msg doted-border">

    <div class="direct-chat-info clearfix">

    <span class="direct-chat-name pull-left">$NAME</span>

    </div>

    <img alt="message user image" src="$IMG" class="direct-chat-img">

    <div class="direct-chat-text">

      $TEXT

    </div>

    <div class="direct-chat-info clearfix">

      <span class="direct-chat-timestamp pull-right">$TIME</span>

    </div>

  </div>

    ]].replace("$IMG", imgLink)

      .replace("$NAME", name)

      .replace("$TIME", time)

      .replace("$TEXT", text));

}

svoid appendButtons(StringBuilder buf, L<S> buttons) {

  S buttonsHtml = lines(map(buttons, func(S text) {

    hsubmit(text, name := "btn")

  }));

	buf.append([[<div class="direct-chat-msg doted-border">

    <div class="direct-chat-buttons">

      $BUTTONS

    </div>

  </div>

    ]].replace("$BUTTONS", buttonsHtml);

}

svoid appendDate(StringBuilder buf, S date) {

  buf.append([[

  <div class="chat-box-single-line">

		<abbr class="timestamp">DATE</abbr>

	</div>]].replace("DATE", date));

}

sS initialMessage() {

  ret thoughtBot.initialMessage();

}

static bool lastUserMessageWas(Conversation conv, S message) {

  Msg m = last(conv.msgs);

  ret m != null && m.fromUser && eq(m.text, message);

}

sS makeReply(S message) {

  ret callStaticAnswerMethod(thoughtBot, message);

}

sS formatTime(long time) {

  ret formatGMT_24(time);

}

sS formatDialog(S id, L<Msg> msgs) {

  new L<S> lc;

  for (Msg m : msgs)

    lc.add(htmlencode((m.fromUser ? "> " : "< ") + m.text));

  ret id + ul(lc);

}

static Conversation getConv(fS cookie) {

  ret withDBLock(func -> Conversation {

    uniq(Conversation, +cookie)

  });

}