import { createReadStream } from "node:fs";
import { access, stat } from "node:fs/promises";
import { createServer } from "node:http";
import path from "node:path";

const root = path.resolve(process.argv[2] ?? "artifacts/storybook/static");
const port = Number(process.argv[3] ?? 6006);
const contentTypes: Readonly<Record<string, string>> = {
  ".css": "text/css; charset=utf-8",
  ".html": "text/html; charset=utf-8",
  ".js": "text/javascript; charset=utf-8",
  ".json": "application/json; charset=utf-8",
  ".svg": "image/svg+xml",
  ".png": "image/png",
};

await access(root);
const server = createServer(async (request, response) => {
  try {
    const url = new URL(request.url ?? "/", `http://127.0.0.1:${port}`);
    const decoded = decodeURIComponent(url.pathname);
    const requested = path.resolve(root, `.${decoded}`);
    if (requested !== root && !requested.startsWith(`${root}${path.sep}`)) {
      response.writeHead(403).end();
      return;
    }
    const details = await stat(requested).catch(() => null);
    const file = details?.isDirectory()
      ? path.join(requested, "index.html")
      : requested;
    await access(file);
    response.writeHead(200, {
      "Content-Type":
        contentTypes[path.extname(file)] ?? "application/octet-stream",
      "Cache-Control": "no-store",
    });
    createReadStream(file).pipe(response);
  } catch {
    response.writeHead(404).end();
  }
});
server.listen(port, "127.0.0.1", () => {
  process.stdout.write(`Static evidence server: ${root} on ${port}\n`);
});
for (const signal of ["SIGINT", "SIGTERM"]) {
  process.on(signal, () => server.close(() => process.exit(0)));
}