import { SITE_URL } from "@/lib/routes";
import { sitemapIds } from "./ids";

/** Sitemap index (robots.txt points here) listing every per-id sitemap generated by app/sitemap.ts. */
export const revalidate = 3600;

export function GET(): Response {
  const now = new Date().toISOString();
  const body = `<?xml version="1.0" encoding="UTF-8"?>
<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
${sitemapIds()
  .map((id) => `  <sitemap><loc>${SITE_URL}/sitemap/${id}.xml</loc><lastmod>${now}</lastmod></sitemap>`)
  .join("\n")}
</sitemapindex>
`;
  return new Response(body, { headers: { "Content-Type": "application/xml; charset=utf-8", "Cache-Control": "public, max-age=3600, s-maxage=3600, stale-while-revalidate=86400" } });
}