import { serve } from "bun";

const port = Number(process.env.PORT ?? "3000");

function contentType(pathname: string): string | undefined {
  if (pathname.endsWith(".html")) return "text/html; charset=utf-8";
  if (pathname.endsWith(".css")) return "text/css; charset=utf-8";
  if (pathname.endsWith(".js")) return "application/javascript; charset=utf-8";
  if (pathname.endsWith(".mjs")) return "application/javascript; charset=utf-8";
  if (pathname.endsWith(".json")) return "application/json; charset=utf-8";
  if (pathname.endsWith(".svg")) return "image/svg+xml";
  if (pathname.endsWith(".png")) return "image/png";
  if (pathname.endsWith(".jpg") || pathname.endsWith(".jpeg")) return "image/jpeg";
  if (pathname.endsWith(".webp")) return "image/webp";
  if (pathname.endsWith(".ico")) return "image/x-icon";
  if (pathname.endsWith(".woff")) return "font/woff";
  if (pathname.endsWith(".woff2")) return "font/woff2";
  if (pathname.endsWith(".txt")) return "text/plain; charset=utf-8";
  return undefined;
}

const distDir = `${process.cwd()}/dist`;

serve({
  port,
  async fetch(req) {
    const url = new URL(req.url);

    // Normalize paths
    let pathname = decodeURIComponent(url.pathname);

    // Default document
    if (pathname === "/") pathname = "/index.html";

    const filePath = `${distDir}${pathname}`;

    // Try direct file first
    let file = Bun.file(filePath);
    if (!(await file.exists())) {
      // If request is for a "route", serve index.html (SPA-ish fallback)
      // Astro static pages typically exist as real files, but this fallback helps
      // if you add client-side routing later.
      file = Bun.file(`${distDir}/index.html`);
      if (!(await file.exists())) {
        return new Response("Not Found", { status: 404 });
      }
    }

    const headers = new Headers();
    const ct = contentType(pathname);
    if (ct) headers.set("Content-Type", ct);

    // Cache policy:
    // - HTML: no-cache (so updates show quickly)
    // - assets: cache long (Astro fingerprints assets by default)
    if (pathname.endsWith(".html")) {
      headers.set("Cache-Control", "no-cache");
    } else {
      headers.set("Cache-Control", "public, max-age=31536000, immutable");
    }

    return new Response(file, { headers });
  }
});

console.log(`Serving dist on http://0.0.0.0:${port}`);