// Dev helper: evaluates JavaScript in the running WebView2 page via the DevTools protocol.
// Usage: node scripts/cdp.mjs "<expression>" [--shot out.png]
import { writeFileSync } from "node:fs";

const args = process.argv.slice(2);
const shotIdx = args.indexOf("--shot");
const shot = shotIdx >= 0 ? args.splice(shotIdx, 2)[1] : null;
const expression = args[0] ?? "document.title";

const targets = await (await fetch("http://127.0.0.1:9222/json")).json();
const page = targets.find((t) => t.type === "page");
if (!page) throw new Error("Keine Seite gefunden");

const ws = new WebSocket(page.webSocketDebuggerUrl);
let id = 0;
const pending = new Map();
ws.onmessage = (event) => {
  const msg = JSON.parse(event.data);
  if (msg.id && pending.has(msg.id)) pending.get(msg.id)(msg);
};
const send = (method, params = {}) =>
  new Promise((resolve) => {
    const myId = ++id;
    pending.set(myId, resolve);
    ws.send(JSON.stringify({ id: myId, method, params }));
  });
await new Promise((resolve) => (ws.onopen = resolve));

const res = await send("Runtime.evaluate", { expression, awaitPromise: true, returnByValue: true });
console.log(JSON.stringify(res.result?.result?.value ?? res.result, null, 2));
if (shot) {
  const img = await send("Page.captureScreenshot", { format: "png" });
  writeFileSync(shot, Buffer.from(img.result.data, "base64"));
}
ws.close();