proxy.ts

import { type NextRequest, NextResponse } from "next/server";

/**
 * Content negotiation for the docs.
 *
 * An agent that asks for Markdown gets the raw file; a browser (which always
 * sends `text/html`) keeps the rendered page. One URL serves both.
 */
export function proxy(request: NextRequest) {
  const accept = request.headers.get("accept")?.toLowerCase() ?? "";
  const wantsMarkdown = accept.includes("text/markdown") || accept.includes("text/plain");
  if (!wantsMarkdown || accept.includes("text/html")) return NextResponse.next();

  const { pathname } = request.nextUrl;
  if (pathname.endsWith(".md")) return NextResponse.next();

  const slug = pathname === "/docs" ? "index" : pathname.slice("/docs/".length);
  if (!slug || slug.includes("/")) return NextResponse.next();

  return NextResponse.rewrite(new URL(`/api/docs/${slug}`, request.url));
}

export const config = {
  matcher: ["/docs", "/docs/:path*"],
};