server.js

// ===========================================================================
//  Covert Chat — SINGLE FILE version.
//  Everything (page, styles, logic, server) is in this one file.
//  No other files or folders are needed.
//
//  Run:   node server.js
//  Then open the URL it prints (usually http://localhost:3000).
// ===========================================================================

const http = require("http");
const crypto = require("crypto");

// ===========================================================================
//  CONFIG  — edit this section to set up your two users, reveal code, etc.
// ===========================================================================
const config = {
  users: {
    "alpha": { name: "Alex", role: "A" },   // role A = sees SCRAMBLED text
    "bravo": { name: "Sam",  role: "B" },    // role B = sees everything normally
  },
  revealCode: "2468",   // code person A types to reveal real messages
  revealSeconds: 15,     // how long real text stays visible
  scramble: {
    mode: "local",       // "local" | "ollama" | "openai"
    ollama: { url: "http://localhost:11434/api/generate", model: "llama3.2:1b" },
    openai: { url: "https://api.openai.com/v1/chat/completions", model: "gpt-4o-mini", apiKey: process.env.OPENAI_API_KEY || "" },
  },
  port: process.env.PORT || 3000,
};

// ===========================================================================
//  SCRAMBLE  — turns a real message into innocuous "cover" text.
// ===========================================================================
const LINES = [
  "yeah that works for me", "sounds good, let me know", "haha yeah totally",
  "ok i'll check and get back to you", "not sure yet, still thinking about it",
  "we should grab coffee sometime", "i'm running a little late honestly",
  "did you see the game last night", "the weather's been so weird lately",
  "i'll probably just stay in tonight", "lol that's hilarious",
  "no worries, take your time", "let's figure it out tomorrow",
  "i totally forgot about that", "sure, whatever's easiest for you",
  "my phone's been dying all day", "traffic was insane this morning",
  "i think i left it at home", "we can talk about it later",
  "that new place is pretty good", "i've been so busy this week",
  "remind me again what time", "yeah i'll send it over in a bit",
  "honestly i could go either way", "cool, see you then",
  "i need more coffee before this", "the dog would not stop barking",
  "i'll ask and see what they say", "maybe next weekend instead",
  "that makes sense i guess", "still waiting to hear back",
  "long day, i'm pretty wiped", "let me double check real quick",
  "sounds like a plan to me", "i'll take care of it, don't worry",
];

function hash(str) {
  let h = 2166136261;
  for (let i = 0; i < str.length; i++) { h ^= str.charCodeAt(i); h = Math.imul(h, 16777619); }
  return h >>> 0;
}

function localScramble(text) {
  const words = text.trim().split(/\s+/).filter(Boolean).length || 1;
  const count = Math.max(1, Math.min(4, Math.round(words / 7)));
  let seed = hash(text);
  const picked = [], used = new Set();
  for (let i = 0; i < count; i++) {
    seed = (Math.imul(seed, 1103515245) + 12345) >>> 0;
    let idx = seed % LINES.length, guard = 0;
    while (used.has(idx) && guard++ < LINES.length) idx = (idx + 1) % LINES.length;
    used.add(idx); picked.push(LINES[idx]);
  }
  return picked.join(". ").replace(/\.\s*\./g, ".");
}

async function ollamaScramble(text, cfg) {
  const prompt = "Rewrite the following message as a completely different, mundane, everyday text message of similar length. Keep it casual and innocuous. Do not reference the original meaning. Output ONLY the rewritten message, nothing else.\n\nMessage: " + text;
  const res = await fetch(cfg.url, { method: "POST", headers: { "Content-Type": "application/json" }, body: JSON.stringify({ model: cfg.model, prompt, stream: false }) });
  const data = await res.json();
  return (data.response || "").trim();
}

async function openaiScramble(text, cfg) {
  const res = await fetch(cfg.url, {
    method: "POST",
    headers: { "Content-Type": "application/json", Authorization: "Bearer " + cfg.apiKey },
    body: JSON.stringify({ model: cfg.model, messages: [
      { role: "system", content: "You rewrite messages as unrelated, mundane, innocuous everyday chat text of similar length. Output only the rewritten message." },
      { role: "user", content: text },
    ] }),
  });
  const data = await res.json();
  return (data.choices?.[0]?.message?.content || "").trim();
}

async function scramble(text, c) {
  try {
    if (c.mode === "ollama") return (await ollamaScramble(text, c.ollama)) || localScramble(text);
    if (c.mode === "openai") return (await openaiScramble(text, c.openai)) || localScramble(text);
  } catch (err) { console.error("[scramble] AI mode failed, using local:", err.message); }
  return localScramble(text);
}

// ===========================================================================
//  PAGE  — the whole front-end, encoded so it needs no separate files.
// ===========================================================================
const PAGE = Buffer.from("<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <title>ChatGPT</title>
  <style>
:root {
  --bg: #212121;
  --sidebar: #171717;
  --panel: #2f2f2f;
  --bubble-user: #2f2f2f;
  --text: #ececec;
  --text-dim: #b4b4b4;
  --border: #3a3a3a;
  --green: #10a37f;
  --accent: #ab68ff;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: "Söhne", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
  font-size: 15px;
  -webkit-font-smoothing: antialiased;
}

.hidden { display: none !important; }

/* ---------- brand dot ---------- */
.brand-dot {
  width: 30px; height: 30px; border-radius: 50%;
  background: conic-gradient(from 180deg, var(--green), #0e8f6f, var(--green));
  margin: 0 auto 18px;
}
.brand-dot.big { width: 46px; height: 46px; margin-bottom: 22px; }

/* ---------- login ---------- */
.login {
  height: 100%;
  display: flex; align-items: center; justify-content: center;
}
.login-box {
  width: 340px; max-width: 90vw;
  text-align: center;
  padding: 40px 32px;
}
.login-box h1 { font-size: 26px; font-weight: 600; margin-bottom: 4px; }
.login-box .sub { color: var(--text-dim); margin-bottom: 26px; font-size: 14px; }
.login-box input {
  width: 100%; padding: 13px 15px; margin-bottom: 12px;
  background: var(--panel); border: 1px solid var(--border);
  border-radius: 10px; color: var(--text); font-size: 15px; outline: none;
}
.login-box input:focus { border-color: var(--green); }
.login-box button {
  width: 100%; padding: 13px; border: none; border-radius: 10px;
  background: var(--text); color: #111; font-weight: 600; font-size: 15px; cursor: pointer;
}
.login-box button:hover { opacity: .9; }
.err { color: #ff6b6b; font-size: 13px; margin-top: 12px; min-height: 16px; }

/* ---------- app layout ---------- */
.app { height: 100%; display: flex; }

/* sidebar */
.sidebar {
  width: 260px; flex-shrink: 0;
  background: var(--sidebar);
  display: flex; flex-direction: column;
  padding: 8px;
}
.new-chat {
  display: flex; align-items: center; gap: 10px;
  width: 100%; padding: 11px 12px; margin-bottom: 6px;
  background: transparent; border: 1px solid var(--border);
  border-radius: 10px; color: var(--text); font-size: 14px; cursor: pointer;
}
.new-chat:hover { background: #2a2a2a; }
.plus { font-size: 18px; line-height: 1; }
.history { flex: 1; overflow-y: auto; padding-top: 6px; }
.history-item {
  padding: 10px 12px; border-radius: 8px; font-size: 14px;
  color: var(--text-dim); cursor: pointer; white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.history-item.active, .history-item:hover { background: #2a2a2a; color: var(--text); }
.sidebar-footer {
  display: flex; align-items: center; gap: 10px;
  padding: 10px 8px; border-top: 1px solid var(--border); font-size: 14px;
}
.avatar {
  width: 28px; height: 28px; border-radius: 50%;
  background: var(--accent); color: #fff;
  display: flex; align-items: center; justify-content: center;
  font-size: 13px; font-weight: 600;
}

/* main */
.main { flex: 1; display: flex; flex-direction: column; min-width: 0; }

.topbar {
  height: 54px; flex-shrink: 0;
  display: flex; align-items: center; gap: 12px;
  padding: 0 16px; position: relative;
}
.model-select {
  background: transparent; border: none; color: var(--text);
  font-size: 16px; font-weight: 600; cursor: pointer;
  padding: 6px 10px; border-radius: 8px;
}
.model-select:hover { background: #2a2a2a; }
.caret { color: var(--text-dim); font-weight: 400; }

.reveal-pop {
  position: absolute; top: 48px; left: 16px; z-index: 20;
  background: var(--panel); border: 1px solid var(--border);
  border-radius: 10px; padding: 8px;
  box-shadow: 0 8px 24px rgba(0,0,0,.4);
}
.reveal-pop input {
  background: #1f1f1f; border: 1px solid var(--border); border-radius: 8px;
  padding: 9px 11px; color: var(--text); font-size: 14px; outline: none; width: 170px;
}
.reveal-pop input:focus { border-color: var(--green); }

.reveal-timer {
  font-size: 12px; color: var(--green); font-weight: 600;
  background: rgba(16,163,127,.12); padding: 4px 10px; border-radius: 20px;
}

/* messages */
.messages { flex: 1; overflow-y: auto; }
.messages .empty {
  height: 100%; display: flex; flex-direction: column;
  align-items: center; justify-content: center; color: var(--text-dim);
}
.messages .empty p { font-size: 20px; color: var(--text); }

.row { width: 100%; padding: 6px 0; display: flex; }
.row-inner {
  max-width: 760px; width: 100%; margin: 0 auto; padding: 0 24px;
  display: flex; gap: 12px;
}
.row.them .row-inner { justify-content: flex-start; }
.row.me .row-inner { justify-content: flex-end; }

.bubble {
  max-width: 75%; padding: 11px 15px; border-radius: 18px;
  line-height: 1.5; white-space: pre-wrap; word-wrap: break-word;
  transition: opacity .15s ease;
}
.row.me .bubble { background: var(--bubble-user); border-bottom-right-radius: 6px; }
.row.them .bubble { background: transparent; padding-left: 0; }

.row.them .row-inner::before {
  content: ""; width: 30px; height: 30px; border-radius: 50%; flex-shrink: 0;
  background: conic-gradient(from 180deg, var(--green), #0e8f6f, var(--green));
}

.bubble.revealed { outline: 1px solid rgba(16,163,127,.5); }

/* composer */
.composer { flex-shrink: 0; padding: 0 16px 14px; }
.composer-inner {
  max-width: 760px; margin: 0 auto;
  display: flex; align-items: flex-end; gap: 8px;
  background: var(--panel); border: 1px solid var(--border);
  border-radius: 26px; padding: 8px 8px 8px 18px;
}
#input {
  flex: 1; background: transparent; border: none; outline: none; resize: none;
  color: var(--text); font-size: 15px; line-height: 1.5; max-height: 180px;
  font-family: inherit; padding: 6px 0;
}
.send-btn {
  width: 34px; height: 34px; border-radius: 50%; border: none;
  background: var(--text); color: #111; font-size: 17px; cursor: pointer; flex-shrink: 0;
}
.send-btn:disabled { background: #555; color: #999; cursor: default; }
.disclaimer { text-align: center; color: var(--text-dim); font-size: 12px; margin-top: 10px; }

/* mobile */
@media (max-width: 720px) {
  .sidebar { display: none; }
  .row-inner { padding: 0 14px; }
}

</style>
  <link rel="icon" href="data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'><circle cx='12' cy='12' r='10' fill='%2310a37f'/></svg>" />
</head>
<body>

  <!-- ===== Login screen ===== -->
  <div id="login" class="login">
    <div class="login-box">
      <div class="brand-dot"></div>
      <h1>ChatGPT</h1>
      <p class="sub">Enter your ID to continue</p>
      <input id="login-id" type="text" placeholder="ID" autocomplete="off" />
      <button id="login-btn">Continue</button>
      <div id="login-err" class="err"></div>
    </div>
  </div>

  <!-- ===== Chat app ===== -->
  <div id="app" class="app hidden">
    <!-- sidebar -->
    <aside class="sidebar">
      <button class="new-chat">
        <span class="plus">+</span> New chat
      </button>
      <div class="history">
        <div class="history-item active">New conversation</div>
      </div>
      <div class="sidebar-footer">
        <div class="avatar" id="side-avatar">U</div>
        <span id="side-name">User</span>
      </div>
    </aside>

    <!-- main -->
    <main class="main">
      <header class="topbar">
        <!-- The model name is the hidden reveal trigger. Clicking it opens
             a small code box; a correct code briefly shows real messages. -->
        <button class="model-select" id="model-select">
          ChatGPT <span class="caret">4o &#9662;</span>
        </button>
        <div id="reveal-timer" class="reveal-timer hidden"></div>

        <!-- hidden code entry, styled like a small dropdown -->
        <div id="reveal-pop" class="reveal-pop hidden">
          <input id="reveal-code" type="password" inputmode="numeric" placeholder="Model access" autocomplete="off" />
        </div>
      </header>

      <div id="messages" class="messages">
        <div class="empty">
          <div class="brand-dot big"></div>
          <p>How can I help you today?</p>
        </div>
      </div>

      <footer class="composer">
        <div class="composer-inner">
          <textarea id="input" rows="1" placeholder="Message ChatGPT…"></textarea>
          <button id="send" class="send-btn" aria-label="Send">&#8593;</button>
        </div>
        <p class="disclaimer">ChatGPT can make mistakes. Check important info.</p>
      </footer>
    </main>
  </div>

  <script>
// ===========================================================================
//  app.js  — client logic
// ===========================================================================

let ME = null;        // { id, name, role }
let evtSource = null;
const msgs = [];      // { id, senderName, text, mine }  (text = what THIS user sees)
let reals = {};       // id -> real text (only populated during a reveal)
let revealed = false;
let revealTimer = null;

const $ = (s) => document.querySelector(s);

// ---------- login ----------
async function login() {
  const id = $("#login-id").value.trim();
  if (!id) return;
  const r = await fetch("/login", {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ id }),
  });
  const data = await r.json();
  if (!data.ok) {
    $("#login-err").textContent = "Invalid ID.";
    return;
  }
  ME = { id, name: data.name, role: data.role };
  startApp();
}

$("#login-btn").addEventListener("click", login);
$("#login-id").addEventListener("keydown", (e) => { if (e.key === "Enter") login(); });

// ---------- start ----------
function startApp() {
  $("#login").classList.add("hidden");
  $("#app").classList.remove("hidden");
  $("#side-name").textContent = ME.name;
  $("#side-avatar").textContent = ME.name[0].toUpperCase();

  evtSource = new EventSource("/events?id=" + encodeURIComponent(ME.id));
  evtSource.addEventListener("message", (e) => {
    const m = JSON.parse(e.data);
    msgs.push(m);
    render();
  });
}

// ---------- render ----------
function render() {
  const box = $("#messages");
  if (msgs.length === 0) return;
  box.innerHTML = "";
  for (const m of msgs) {
    const row = document.createElement("div");
    row.className = "row " + (m.mine ? "me" : "them");
    const inner = document.createElement("div");
    inner.className = "row-inner";
    const bubble = document.createElement("div");
    bubble.className = "bubble";

    // During a reveal, show the real text if we have it.
    if (revealed && reals[m.id] !== undefined) {
      bubble.textContent = reals[m.id];
      bubble.classList.add("revealed");
    } else {
      bubble.textContent = m.text;
    }

    inner.appendChild(bubble);
    row.appendChild(inner);
    box.appendChild(row);
  }
  box.scrollTop = box.scrollHeight;
}

// ---------- send ----------
const input = $("#input");
const sendBtn = $("#send");

function autoGrow() {
  input.style.height = "auto";
  input.style.height = Math.min(input.scrollHeight, 180) + "px";
}
input.addEventListener("input", autoGrow);

async function send() {
  const text = input.value.trim();
  if (!text) return;
  input.value = "";
  autoGrow();
  await fetch("/send", {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ id: ME.id, text }),
  });
  // We intentionally do NOT echo the typed text locally — we wait for the
  // server to push it back, so person A sees the scrambled version even for
  // their own messages.
}

sendBtn.addEventListener("click", send);
input.addEventListener("keydown", (e) => {
  if (e.key === "Enter" && !e.shiftKey) { e.preventDefault(); send(); }
});

// ---------- hidden reveal ----------
// Clicking the "model name" opens a small code box. This is deliberately
// unlabeled / disguised as a normal part of the ChatGPT UI.
const modelBtn = $("#model-select");
const pop = $("#reveal-pop");
const codeInput = $("#reveal-code");

modelBtn.addEventListener("click", () => {
  // Only person A has anything to reveal; for person B this just looks inert.
  pop.classList.toggle("hidden");
  if (!pop.classList.contains("hidden")) codeInput.focus();
});

document.addEventListener("click", (e) => {
  if (!pop.contains(e.target) && e.target !== modelBtn && !modelBtn.contains(e.target)) {
    pop.classList.add("hidden");
  }
});

codeInput.addEventListener("keydown", async (e) => {
  if (e.key !== "Enter") return;
  const code = codeInput.value.trim();
  codeInput.value = "";
  pop.classList.add("hidden");

  const r = await fetch("/reveal", {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ id: ME.id, code }),
  });
  const data = await r.json();
  if (!data.ok) return; // wrong code: silently do nothing

  reals = data.reals;
  startReveal(data.seconds);
});

function startReveal(seconds) {
  revealed = true;
  render();

  const timerEl = $("#reveal-timer");
  timerEl.classList.remove("hidden");
  let left = seconds;
  timerEl.textContent = left + "s";

  clearInterval(revealTimer);
  revealTimer = setInterval(() => {
    left -= 1;
    if (left <= 0) {
      clearInterval(revealTimer);
      revealed = false;
      reals = {};
      timerEl.classList.add("hidden");
      render();
    } else {
      timerEl.textContent = left + "s";
    }
  }, 1000);
}

</script>
</body>
</html>
", "base64").toString("utf8");

// ===========================================================================
//  SERVER
// ===========================================================================
const messages = [];
const clients = [];

// ----- Saving messages (optional, via free Upstash Redis) ------------------
//  Set these two environment variables on your host to turn on saving:
//    UPSTASH_REDIS_REST_URL    (from your Upstash database page)
//    UPSTASH_REDIS_REST_TOKEN  (from your Upstash database page)
//  If they are not set, the app just keeps messages in memory (fine for
//  running locally). Upstash's REST API is plain HTTP, so no extra installs.
const REDIS_URL = process.env.UPSTASH_REDIS_REST_URL || "";
const REDIS_TOKEN = process.env.UPSTASH_REDIS_REST_TOKEN || "";
const STORE_KEY = process.env.STORE_KEY || "covertchat:messages";
const persistence = Boolean(REDIS_URL && REDIS_TOKEN);

async function redisCommand(cmd) {
  const res = await fetch(REDIS_URL, {
    method: "POST",
    headers: { Authorization: "Bearer " + REDIS_TOKEN, "Content-Type": "application/json" },
    body: JSON.stringify(cmd),
  });
  if (!res.ok) throw new Error("Redis HTTP " + res.status);
  return res.json();
}

async function loadMessages() {
  if (!persistence) return;
  try {
    const out = await redisCommand(["GET", STORE_KEY]);
    if (out && out.result) {
      const arr = JSON.parse(out.result);
      if (Array.isArray(arr)) { messages.length = 0; messages.push(...arr); }
    }
    console.log("  Loaded " + messages.length + " saved message(s).");
  } catch (err) { console.error("  Could not load saved messages:", err.message); }
}

async function saveMessages() {
  if (!persistence) return;
  try { await redisCommand(["SET", STORE_KEY, JSON.stringify(messages)]); }
  catch (err) { console.error("  Could not save messages:", err.message); }
}

function userFromId(id) { return config.users[(id || "").trim()] || null; }
function viewFor(role, m) {
  return { id: m.id, senderName: m.senderName, ts: m.ts, mine: m.senderRole === role, text: role === "A" ? m.coverText : m.realText };
}
function sendEvent(client, event, payload) {
  client.res.write("event: " + event + "\n");
  client.res.write("data: " + JSON.stringify(payload) + "\n\n");
}
function broadcast(m) { for (const c of clients) sendEvent(c, "message", viewFor(c.role, m)); }
function readBody(req) {
  return new Promise((resolve) => {
    let data = ""; req.on("data", (c) => (data += c));
    req.on("end", () => { try { resolve(JSON.parse(data || "{}")); } catch { resolve({}); } });
  });
}
function json(res, code, obj) { res.writeHead(code, { "Content-Type": "application/json" }); res.end(JSON.stringify(obj)); }

const server = http.createServer(async (req, res) => {
  const url = new URL(req.url, "http://localhost");

  if (req.method === "POST" && url.pathname === "/login") {
    const body = await readBody(req);
    const user = userFromId(body.id);
    if (!user) return json(res, 401, { ok: false });
    return json(res, 200, { ok: true, name: user.name, role: user.role });
  }

  if (req.method === "GET" && url.pathname === "/events") {
    const user = userFromId(url.searchParams.get("id"));
    if (!user) { res.writeHead(401); return res.end(); }
    res.writeHead(200, { "Content-Type": "text/event-stream", "Cache-Control": "no-cache", Connection: "keep-alive" });
    res.write("\n");
    const client = { res, role: user.role };
    clients.push(client);
    for (const m of messages) sendEvent(client, "message", viewFor(user.role, m));
    const ping = setInterval(() => res.write(": ping\n\n"), 25000);
    req.on("close", () => { clearInterval(ping); const i = clients.indexOf(client); if (i >= 0) clients.splice(i, 1); });
    return;
  }

  if (req.method === "POST" && url.pathname === "/send") {
    const body = await readBody(req);
    const user = userFromId(body.id);
    const text = (body.text || "").trim();
    if (!user || !text) return json(res, 400, { ok: false });
    const coverText = await scramble(text, config.scramble);
    const m = { id: crypto.randomUUID(), senderRole: user.role, senderName: user.name, realText: text, coverText, ts: Date.now() };
    messages.push(m); broadcast(m);
    await saveMessages();
    return json(res, 200, { ok: true });
  }

  if (req.method === "POST" && url.pathname === "/reveal") {
    const body = await readBody(req);
    const user = userFromId(body.id);
    if (!user || user.role !== "A") return json(res, 403, { ok: false });
    if (String(body.code) !== String(config.revealCode)) return json(res, 401, { ok: false });
    const reals = {};
    for (const m of messages) reals[m.id] = m.realText;
    return json(res, 200, { ok: true, reals, seconds: config.revealSeconds });
  }

  // Any other GET serves the app.
  if (req.method === "GET") { res.writeHead(200, { "Content-Type": "text/html" }); return res.end(PAGE); }

  res.writeHead(404); res.end("Not found");
});

let currentPort = Number(config.port) || 3000;
const basePort = currentPort;
server.on("listening", () => {
  const port = server.address().port;
  console.log("\n  Chat is running. Open this in your browser:\n");
  console.log("        http://localhost:" + port + "\n");
  console.log("  Scramble mode: " + config.scramble.mode);
  console.log("  Saving messages: " + (persistence ? "ON (Upstash)" : "off (in-memory only)"));
  console.log("  Logins: " + Object.keys(config.users).map((k) => k + " (" + config.users[k].role + ")").join(", ") + "\n");
});
server.on("error", (err) => {
  if (err.code === "EADDRINUSE") {
    if (currentPort - basePort < 10) { console.log("  Port " + currentPort + " is busy — trying " + (currentPort + 1) + "..."); currentPort += 1; setTimeout(() => server.listen(currentPort), 150); }
    else { console.error("\n  Ports " + basePort + "-" + currentPort + " are all in use. Change \"port\" in the config at the top of this file.\n"); process.exit(1); }
  } else { throw err; }
});
loadMessages().finally(() => server.listen(currentPort));