middleware.ts

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

const { auth } = NextAuth(authConfig);

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

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

  if (isApiAuthRoute) {
    return;
  }

  if (isAuthRoute) {
    if (isLoggedIn) {
      return Response.redirect(new URL(DEFAULT_LOGIN_REDIRECT, nextUrl));
      // return NextResponse.redirect(new URL("/settings", nextUrl));
      // The second argument to the URL constructor serves as the base URL. When the first argument (DEFAULT_LOGIN_REDIRECT) is a relative URL (like /login), the nextUrl provides the context for
    }
    return;
  }

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

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

  return;
});

export const config = {
  matcher: [
    "/((?!_next|[^?]*\\.(?:html?|css|js(?!on)|jpe?g|webp|png|gif|svg|ttf|woff2?|ico|csv|docx?|xlsx?|zip|webmanifest)).*)",
    // Always run for API routes
    "/(api|trpc)(.*)",
  ],
};