// middleware.ts
import { NextResponse } from "next/server";
import type { NextRequest } from "next/server";

const LAUNCH_ONLY_ROOT = process.env.NEXT_PUBLIC_LAUNCH_ONLY_ROOT === "true";

// ✅ Forever allow list (always reachable even during launch-only mode)
const ALWAYS_ALLOW = new Set<string>([
  "/",
  "/favicon.ico",
  "/robots.txt",
  "/sitemap.xml",
]);

// Match common public/static file extensions so middleware never blocks them
const PUBLIC_FILE = /\.(?:svg|png|jpg|jpeg|gif|webp|ico|css|js|map|txt|xml|json|woff|woff2|ttf|eot)$/i;

export function middleware(req: NextRequest) {
  if (!LAUNCH_ONLY_ROOT) return NextResponse.next();

  const { pathname } = req.nextUrl;

  // ✅ Always allow Next internals + static assets (public/ and _next/)
  if (
    pathname.startsWith("/_next") ||
    pathname.startsWith("/favicon") ||
    pathname === "/robots.txt" ||
    pathname === "/sitemap.xml" ||
    PUBLIC_FILE.test(pathname)
  ) {
    return NextResponse.next();
  }

  // ✅ Allow the root + a few public files
  if (ALWAYS_ALLOW.has(pathname)) return NextResponse.next();

  // 🚫 Everything else: hide it
  return NextResponse.rewrite(new URL("/404", req.url));
}

export const config = {
  // Run middleware on everything *except* Next internals and obvious static files.
  // This keeps launch gating from ever breaking your logo/images/fonts/etc.
  matcher: [
    "/((?!_next/static|_next/image|favicon.ico|robots.txt|sitemap.xml|.*\\.(?:svg|png|jpg|jpeg|gif|webp|ico|css|js|map|txt|xml|json|woff|woff2|ttf|eot)).*)",
  ],
};