// Serveur de prévisualisation QA (zéro dépendance) : sert un build Vite
// (dist-next par défaut) et relaie /api vers le backend local — permet de
// valider une fiche avec Playwright SANS toucher au dist/ servi en production.
// Usage : node frontend/scripts/preview.mjs [dir=dist-next] [port=18096] [api=http://127.0.0.1:8096]
import http from "node:http";
import { createReadStream, existsSync, statSync } from "node:fs";
import { extname, join, resolve } from "node:path";

const DIR = resolve(process.argv[2] || "dist-next");
const PORT = Number(process.argv[3] || 18096);
const API = new URL(process.argv[4] || "http://127.0.0.1:8096");
const MIME = { ".html": "text/html; charset=utf-8", ".js": "text/javascript", ".css": "text/css", ".svg": "image/svg+xml",
  ".png": "image/png", ".json": "application/json", ".geojson": "application/geo+json", ".woff2": "font/woff2", ".ico": "image/x-icon" };

http.createServer((req, res) => {
  const url = new URL(req.url, "http://x");
  if (url.pathname.startsWith("/api/")) {
    const p = http.request({ host: API.hostname, port: API.port, path: req.url, method: req.method, headers: { ...req.headers, host: API.host } },
      (r) => { res.writeHead(r.statusCode, r.headers); r.pipe(res); });
    p.on("error", () => { res.writeHead(502); res.end("api down"); });
    req.pipe(p);
    return;
  }
  let f = join(DIR, decodeURIComponent(url.pathname));
  if (!existsSync(f) || statSync(f).isDirectory()) f = join(DIR, "index.html");
  res.writeHead(200, { "content-type": MIME[extname(f)] || "application/octet-stream" });
  createReadStream(f).pipe(res);
}).listen(PORT, "127.0.0.1", () => console.log(`preview ${DIR} → http://127.0.0.1:${PORT} (api → ${API.origin})`));