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

const LOCALES = ["zh", "en"] as const;
const DEFAULT_LOCALE = "zh";

function proxy(request: NextRequest) {
  const pathname = request.nextUrl.pathname;

  // 检查路径是否已有 locale 前缀
  const hasLocale = LOCALES.some(
    (loc) => pathname === `/${loc}` || pathname.startsWith(`/${loc}/`)
  );

  if (hasLocale) {
    return NextResponse.next();
  }

  // 根路径或无效路径，重定向到默认 locale
  const url = request.nextUrl.clone();
  url.pathname = `/${DEFAULT_LOCALE}${pathname === "/" ? "" : pathname}`;
  return NextResponse.redirect(url);
}

export { proxy };

export const config = {
  matcher: ["/((?!api|trpc|_next|_vercel|.*\\..*).*)"],
};