middleware.ts

import {
  DEFAULT_LOGIN_REDIRECT,
  apiAuthPrefix,
  authRoutes,
  publicRoutes,
} from "@/routes";
import NextAuth from "next-auth";
import { authOptions } from "./lib/auth.config";

const { auth } = NextAuth(authOptions);

const matchRoute = (routes: (string | RegExp)[], pathname: string) => {
  for (const route of routes) {
    if (route instanceof RegExp) {
      if (pathname.match(route)) {
        return true;
      }
    } else if (route === pathname) {
      return true;
    }
  }
  return false;
};

export default auth((req) => {
  const { nextUrl } = req;
  const isLoggedIn = !!req.auth;

  const isApiAuthRoute = nextUrl.pathname.startsWith(apiAuthPrefix);
  const isPublicRoute = matchRoute(publicRoutes, nextUrl.pathname);
  const isAuthRoute = authRoutes.includes(nextUrl.pathname);

  if (isApiAuthRoute) {
    return null;
  }

  if (isAuthRoute) {
    if (isLoggedIn) {
      return Response.redirect(new URL(DEFAULT_LOGIN_REDIRECT, nextUrl));
    }
    return null;
  }

  if (!isLoggedIn && !isPublicRoute) {
    let callbackUrl = nextUrl.pathname;
    if (nextUrl.search) {
      callbackUrl += nextUrl.search;
    }

    const encodedCallbackUrl = encodeURIComponent(callbackUrl);

    return Response.redirect(
      new URL(`/login?callbackUrl=${encodedCallbackUrl}`, nextUrl)
    );
  }

  return null;
});

// Optionally, don't invoke Middleware on some paths
export const config = {
  matcher: ["/((?!.+\\.[\\w]+$|_next).*)", "/", "/(api|trpc)(.*)"],
};