#!/usr/bin/env node
/**
 * cdp_net_capture.js —— 用 CDP 抓某个标签页的网络请求(含 postData), 用于拿到
 * 前端**现场生成**的请求体 (如 1ms 的 /api/v1/captcha/params 里的 identity_context)。
 *
 * 零依赖: 只用 Node >= 22 内置 WebSocket / fetch。
 *
 * 用法:
 *   node tools/cdp_net_capture.js --port 9222 --match 1ms.run --url-substr captcha/params --reload
 *   node tools/cdp_net_capture.js --match 1ms.run --url-substr captcha/params --reload --wait 6000
 */
const fs = require('fs');

function arg(name, def) {
    const i = process.argv.indexOf('--' + name);
    if (i < 0) return def;
    const v = process.argv[i + 1];
    return (v === undefined || v.startsWith('--')) ? true : v;
}

class Cdp {
    constructor(ws) { this.ws = ws; this.id = 0; this.waits = new Map(); this.handlers = []; }
    static async connect(url) {
        const ws = new WebSocket(url);
        await new Promise((res, rej) => { ws.onopen = res; ws.onerror = rej; });
        const c = new Cdp(ws);
        ws.onmessage = ev => {
            const m = JSON.parse(ev.data);
            if (m.id && c.waits.has(m.id)) {
                const { res, rej } = c.waits.get(m.id);
                c.waits.delete(m.id);
                m.error ? rej(new Error(JSON.stringify(m.error))) : res(m.result);
            } else if (m.method) {
                for (const h of c.handlers) h(m);
            }
        };
        return c;
    }
    send(method, params = {}) {
        const id = ++this.id;
        this.ws.send(JSON.stringify({ id, method, params }));
        return new Promise((res, rej) => this.waits.set(id, { res, rej }));
    }
    on(fn) { this.handlers.push(fn); }
    close() { try { this.ws.close(); } catch (e) {} }
}
const sleep = ms => new Promise(r => setTimeout(r, ms));

(async () => {
    const port = parseInt(arg('port', '9222'), 10);
    const match = arg('match', null);
    const substr = arg('url-substr', null);
    const wait = parseInt(arg('wait', '8000'), 10);

    const targets = (await (await fetch(`http://127.0.0.1:${port}/json/list`)).json())
        .filter(t => t.type === 'page');
    let target = match ? targets.find(t => (t.url || '').includes(match)) : targets[0];
    if (!target) throw new Error('没有可用标签页');

    const cdp = await Cdp.connect(target.webSocketDebuggerUrl);
    const reqs = [];
    cdp.on(m => {
        if (m.method === 'Network.requestWillBeSent') {
            const r = m.params.request;
            if (!substr || r.url.includes(substr)) {
                reqs.push({
                    url: r.url, method: r.method, headers: r.headers,
                    postData: r.postData || null, at: Date.now(),
                });
            }
        }
    });
    await cdp.send('Network.enable');
    await cdp.send('Page.enable');
    if (arg('reload', false)) {
        await cdp.send('Page.reload', { ignoreCache: true });
    }
    await sleep(wait);
    console.log(JSON.stringify({ target: target.url, captured: reqs }, null, 2));
    cdp.close();
})().catch(e => { console.error('CDP_ERROR: ' + e.message); process.exit(1); });