feat(web): add whatsapp QR login tool

src/web/login-qr.ts

@@ -0,0 +1,193 @@
+import { randomUUID } from "node:crypto";
+
+import { danger, info, success } from "../globals.js";
+import { logInfo } from "../logger.js";
+import { defaultRuntime, type RuntimeEnv } from "../runtime.js";
+import {
+  createWaSocket,
+  formatError,
+  readWebSelfId,
+  waitForWaConnection,
+  webAuthExists,
+} from "./session.js";
+import { renderQrPngBase64 } from "./qr-image.js";
+
+type WaSocket = Awaited<ReturnType<typeof createWaSocket>>;
+
+type ActiveLogin = {
+  id: string;
+  sock: WaSocket;
+  startedAt: number;
+  qr?: string;
+  qrDataUrl?: string;
+  connected: boolean;
+  error?: string;
+  waitPromise: Promise<void>;
+};
+
+const ACTIVE_LOGIN_TTL_MS = 3 * 60_000;
+let activeLogin: ActiveLogin | null = null;
+
+function closeSocket(sock: WaSocket) {
+  try {
+    sock.ws?.close();
+  } catch {
+    // ignore
+  }
+}
+
+async function resetActiveLogin(reason?: string) {
+  if (activeLogin) {
+    closeSocket(activeLogin.sock);
+    activeLogin = null;
+  }
+  if (reason) {
+    logInfo(reason);
+  }
+}
+
+function isLoginFresh(login: ActiveLogin) {
+  return Date.now() - login.startedAt < ACTIVE_LOGIN_TTL_MS;
+}
+
+export async function startWebLoginWithQr(
+  opts: {
+    verbose?: boolean;
+    timeoutMs?: number;
+    force?: boolean;
+    runtime?: RuntimeEnv;
+  } = {},
+): Promise<{ qrDataUrl?: string; message: string }> {
+  const runtime = opts.runtime ?? defaultRuntime;
+  const hasWeb = await webAuthExists();
+  const selfId = readWebSelfId();
+  if (hasWeb && !opts.force) {
+    const who = selfId.e164 ?? selfId.jid ?? "unknown";
+    return {
+      message: `WhatsApp is already linked (${who}). Say “relink” if you want a fresh QR.`,
+    };
+  }
+
+  if (activeLogin && isLoginFresh(activeLogin) && activeLogin.qrDataUrl) {
+    return {
+      qrDataUrl: activeLogin.qrDataUrl,
+      message: "QR already active. Scan it in WhatsApp → Linked Devices.",
+    };
+  }
+
+  await resetActiveLogin();
+
+  let resolveQr: ((qr: string) => void) | null = null;
+  let rejectQr: ((err: Error) => void) | null = null;
+  const qrPromise = new Promise<string>((resolve, reject) => {
+    resolveQr = resolve;
+    rejectQr = reject;
+  });
+
+  const qrTimer = setTimeout(() => {
+    rejectQr?.(new Error("Timed out waiting for WhatsApp QR"));
+  }, Math.max(opts.timeoutMs ?? 30_000, 5000));
+
+  let sock: WaSocket;
+  try {
+    sock = await createWaSocket(false, Boolean(opts.verbose), {
+      onQr: (qr: string) => {
+        if (!activeLogin || activeLogin.qr) return;
+        activeLogin.qr = qr;
+        clearTimeout(qrTimer);
+        runtime.log(info("WhatsApp QR received."));
+        resolveQr?.(qr);
+      },
+    });
+  } catch (err) {
+    clearTimeout(qrTimer);
+    await resetActiveLogin();
+    return {
+      message: `Failed to start WhatsApp login: ${String(err)}`,
+    };
+  }
+  const login: ActiveLogin = {
+    id: randomUUID(),
+    sock,
+    startedAt: Date.now(),
+    connected: false,
+    waitPromise: Promise.resolve(),
+  };
+  activeLogin = login;
+
+  login.waitPromise = waitForWaConnection(sock)
+    .then(() => {
+      if (activeLogin?.id === login.id) {
+        activeLogin.connected = true;
+      }
+    })
+    .catch((err) => {
+      if (activeLogin?.id === login.id) {
+        activeLogin.error = formatError(err);
+      }
+    });
+
+  let qr: string;
+  try {
+    qr = await qrPromise;
+  } catch (err) {
+    clearTimeout(qrTimer);
+    await resetActiveLogin();
+    return {
+      message: `Failed to get QR: ${String(err)}`,
+    };
+  }
+
+  const base64 = await renderQrPngBase64(qr);
+  login.qrDataUrl = `data:image/png;base64,${base64}`;
+  return {
+    qrDataUrl: login.qrDataUrl,
+    message: "Scan this QR in WhatsApp → Linked Devices.",
+  };
+}
+
+export async function waitForWebLogin(
+  opts: { timeoutMs?: number; runtime?: RuntimeEnv } = {},
+): Promise<{ connected: boolean; message: string }> {
+  const runtime = opts.runtime ?? defaultRuntime;
+  if (!activeLogin) {
+    return { connected: false, message: "No active WhatsApp login in progress." };
+  }
+
+  const login = activeLogin;
+  if (!isLoginFresh(login)) {
+    await resetActiveLogin();
+    return {
+      connected: false,
+      message: "The login QR expired. Ask me to generate a new one.",
+    };
+  }
+  const timeoutMs = Math.max(opts.timeoutMs ?? 120_000, 1000);
+  const timeout = new Promise<"timeout">((resolve) =>
+    setTimeout(() => resolve("timeout"), timeoutMs),
+  );
+  const result = await Promise.race([login.waitPromise.then(() => "done"), timeout]);
+
+  if (result === "timeout") {
+    return {
+      connected: false,
+      message: "Still waiting for the QR scan. Let me know when you’ve scanned it.",
+    };
+  }
+
+  if (login.error) {
+    const message = `WhatsApp login failed: ${login.error}`;
+    await resetActiveLogin(message);
+    runtime.log(danger(message));
+    return { connected: false, message };
+  }
+
+  if (login.connected) {
+    const message = "✅ Linked! WhatsApp is ready.";
+    runtime.log(success(message));
+    await resetActiveLogin();
+    return { connected: true, message };
+  }
+
+  return { connected: false, message: "Login ended without a connection." };
+}

src/web/qr-image.test.ts

@@ -0,0 +1,11 @@
+import { describe, expect, it } from "vitest";
+
+import { renderQrPngBase64 } from "./qr-image.js";
+
+describe("renderQrPngBase64", () => {
+  it("renders a PNG data payload", async () => {
+    const b64 = await renderQrPngBase64("clawdis");
+    const buf = Buffer.from(b64, "base64");
+    expect(buf.subarray(0, 8).toString("hex")).toBe("89504e470d0a1a0a");
+  });
+});

src/web/qr-image.ts

@@ -0,0 +1,133 @@
+import { createRequire } from "node:module";
+import { deflateSync } from "node:zlib";
+
+type QRCodeConstructor = new (
+  typeNumber: number,
+  errorCorrectLevel: unknown,
+) => {
+  addData: (data: string) => void;
+  make: () => void;
+  getModuleCount: () => number;
+  isDark: (row: number, col: number) => boolean;
+};
+
+const require = createRequire(import.meta.url);
+const QRCode = require(
+  "qrcode-terminal/vendor/QRCode",
+) as QRCodeConstructor;
+const QRErrorCorrectLevel = require(
+  "qrcode-terminal/vendor/QRCode/QRErrorCorrectLevel",
+) as Record<string, unknown>;
+
+function createQrMatrix(input: string) {
+  const qr = new QRCode(-1, QRErrorCorrectLevel.L);
+  qr.addData(input);
+  qr.make();
+  return qr;
+}
+
+function fillPixel(
+  buf: Buffer,
+  x: number,
+  y: number,
+  width: number,
+  r: number,
+  g: number,
+  b: number,
+  a = 255,
+) {
+  const idx = (y * width + x) * 4;
+  buf[idx] = r;
+  buf[idx + 1] = g;
+  buf[idx + 2] = b;
+  buf[idx + 3] = a;
+}
+
+function crcTable() {
+  const table = new Uint32Array(256);
+  for (let i = 0; i < 256; i += 1) {
+    let c = i;
+    for (let k = 0; k < 8; k += 1) {
+      c = c & 1 ? 0xedb88320 ^ (c >>> 1) : c >>> 1;
+    }
+    table[i] = c >>> 0;
+  }
+  return table;
+}
+
+const CRC_TABLE = crcTable();
+
+function crc32(buf: Buffer) {
+  let crc = 0xffffffff;
+  for (let i = 0; i < buf.length; i += 1) {
+    crc = CRC_TABLE[(crc ^ buf[i]) & 0xff] ^ (crc >>> 8);
+  }
+  return (crc ^ 0xffffffff) >>> 0;
+}
+
+function pngChunk(type: string, data: Buffer) {
+  const typeBuf = Buffer.from(type, "ascii");
+  const len = Buffer.alloc(4);
+  len.writeUInt32BE(data.length, 0);
+  const crc = crc32(Buffer.concat([typeBuf, data]));
+  const crcBuf = Buffer.alloc(4);
+  crcBuf.writeUInt32BE(crc, 0);
+  return Buffer.concat([len, typeBuf, data, crcBuf]);
+}
+
+function encodePngRgba(buffer: Buffer, width: number, height: number) {
+  const stride = width * 4;
+  const raw = Buffer.alloc((stride + 1) * height);
+  for (let row = 0; row < height; row += 1) {
+    const rawOffset = row * (stride + 1);
+    raw[rawOffset] = 0; // filter: none
+    buffer.copy(raw, rawOffset + 1, row * stride, row * stride + stride);
+  }
+  const compressed = deflateSync(raw);
+
+  const signature = Buffer.from([0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a]);
+  const ihdr = Buffer.alloc(13);
+  ihdr.writeUInt32BE(width, 0);
+  ihdr.writeUInt32BE(height, 4);
+  ihdr[8] = 8; // bit depth
+  ihdr[9] = 6; // color type RGBA
+  ihdr[10] = 0; // compression
+  ihdr[11] = 0; // filter
+  ihdr[12] = 0; // interlace
+
+  return Buffer.concat([
+    signature,
+    pngChunk("IHDR", ihdr),
+    pngChunk("IDAT", compressed),
+    pngChunk("IEND", Buffer.alloc(0)),
+  ]);
+}
+
+export async function renderQrPngBase64(
+  input: string,
+  opts: { scale?: number; marginModules?: number } = {},
+): Promise<string> {
+  const { scale = 6, marginModules = 4 } = opts;
+  const qr = createQrMatrix(input);
+  const modules = qr.getModuleCount();
+  const size = (modules + marginModules * 2) * scale;
+
+  const buf = Buffer.alloc(size * size * 4, 255);
+  for (let row = 0; row < modules; row += 1) {
+    for (let col = 0; col < modules; col += 1) {
+      if (!qr.isDark(row, col)) continue;
+      const startX = (col + marginModules) * scale;
+      const startY = (row + marginModules) * scale;
+      for (let y = 0; y < scale; y += 1) {
+        const pixelY = startY + y;
+        for (let x = 0; x < scale; x += 1) {
+          const pixelX = startX + x;
+          fillPixel(buf, pixelX, pixelY, size, 0, 0, 0, 255);
+        }
+      }
+    }
+  }
+
+  const png = encodePngRgba(buf, size, size);
+  return png.toString("base64");
+}

src/web/session.ts

@@ -83,7 +83,11 @@ async function safeSaveCreds(
  * Create a Baileys socket backed by the multi-file auth store we keep on disk.
  * Consumers can opt into QR printing for interactive login flows.
  */
-export async function createWaSocket(printQr: boolean, verbose: boolean) {
+export async function createWaSocket(
+  printQr: boolean,
+  verbose: boolean,
+  opts: { onQr?: (qr: string) => void } = {},
+) {
   const baseLogger = getChildLogger(
     { module: "baileys" },
     {
@@ -115,9 +119,12 @@ export async function createWaSocket(printQr: boolean, verbose: boolean) {
     (update: Partial<import("@whiskeysockets/baileys").ConnectionState>) => {
       try {
         const { connection, lastDisconnect, qr } = update;
-        if (qr && printQr) {
-          console.log("Scan this QR in WhatsApp (Linked Devices):");
-          qrcode.generate(qr, { small: true });
+        if (qr) {
+          opts.onQr?.(qr);
+          if (printQr) {
+            console.log("Scan this QR in WhatsApp (Linked Devices):");
+            qrcode.generate(qr, { small: true });
+          }
         }
         if (connection === "close") {
           const status = getStatusCode(lastDisconnect?.error);