tsms/src/middleware.ts

import { NextRequestWithAuth, withAuth } from "next-auth/middleware";
import { authOptions } from "@/config/authConfig";
import { NextFetchEvent, NextResponse } from "next/server";

const PUBLIC_ROUTES = ["/login", "/logout"];
const LANG_QUERY_PARAM = "lang";

const authMiddleware = withAuth({
  pages: authOptions.pages,
});

export default async function middleware(
  req: NextRequestWithAuth,
  event: NextFetchEvent,
) {
  const langPref = req.nextUrl.searchParams.get(LANG_QUERY_PARAM);
  if (langPref) {
    // Redirect to same url without the lang query param + set cookies
    const newUrl = new URL(req.nextUrl);
    newUrl.searchParams.delete(LANG_QUERY_PARAM);
    const response = NextResponse.redirect(newUrl);
    response.cookies.set("i18next", langPref);
    return response;
  }

  // Matcher for using the auth middleware
  return PUBLIC_ROUTES.some((route) => req.nextUrl.pathname.startsWith(route))
    ? NextResponse.next() // Return normal response
    : await authMiddleware(req, event); // Let auth middleware handle response
}