import { cp, mkdir } from "node:fs/promises";
import { existsSync } from "node:fs";
import { spawn } from "node:child_process";
import path from "node:path";

const root = process.cwd();
const standalone = path.join(root, ".next", "standalone");
const server = path.join(standalone, "server.js");

if (!existsSync(server)) {
  console.error("Standalone build not found. Run npm run build before npm start.");
  process.exit(1);
}

await mkdir(path.join(standalone, ".next"), { recursive: true });
await cp(path.join(root, ".next", "static"), path.join(standalone, ".next", "static"), { recursive: true, force: true });
if (existsSync(path.join(root, "public"))) {
  await cp(path.join(root, "public"), path.join(standalone, "public"), { recursive: true, force: true });
}

const child = spawn(process.execPath, [server], {
  cwd: standalone,
  env: process.env,
  stdio: "inherit",
});

for (const signal of ["SIGINT", "SIGTERM"]) {
  process.on(signal, () => child.kill(signal));
}

child.on("exit", (code, signal) => {
  if (signal) process.kill(process.pid, signal);
  process.exit(code ?? 0);
});