middleware.ts

import { createServerClient, type CookieOptions } from "@supabase/ssr";
import { NextResponse, type NextRequest } from "next/server";

export async function middleware(request: NextRequest) {
  let response = NextResponse.next({
    request: {
      headers: request.headers,
    },
  });

  const path = new URL(request.url).pathname;

  const protectedRoutes = ["/dashboard"];
  const authRoutes = ["/signup", "/signin", "/forgot-password"];
  const publicRoutes = ["/"];

  const isProtectedRoute = protectedRoutes.includes(path);
  const isAuthRoute = authRoutes.includes(path);
  const isPublicRoute = publicRoutes.includes(path);

  if (isPublicRoute) {
    const user = await getUser(request, response);

    if (user) {
      console.log(user);
      return NextResponse.redirect(new URL("/dashboard", request.url));
    }
  }

  if (isProtectedRoute || isAuthRoute) {
    const user = await getUser(request, response);

    if (isProtectedRoute && !user) {
      return NextResponse.redirect(new URL("/signin", request.url));
    }

    if (isAuthRoute && user) {
      return NextResponse.redirect(new URL("/dashboard", request.url));
    }
  }

  return response;
}

export const config = {
  matcher: [
    "/((?!_next/static|_next/image|favicon.ico|.*\\.(?:svg|png|jpg|jpeg|gif|webp)$).*)",
  ],
};

async function getUser(request: NextRequest, response: NextResponse) {
  const supabaseClient = createServerClient(
    process.env.NEXT_PUBLIC_SUPABASE_URL!,
    process.env.NEXT_PUBLIC_SUPABASE_ANON_KEY!,
    {
      cookies: {
        get(name: string) {
          return request.cookies.get(name)?.value;
        },
        set(name: string, value: string, options: CookieOptions) {
          request.cookies.set({
            name,
            value,
            ...options,
          });
          response = NextResponse.next({
            request: {
              headers: request.headers,
            },
          });
          response.cookies.set({
            name,
            value,
            ...options,
          });
        },
        remove(name: string, options: CookieOptions) {
          request.cookies.set({
            name,
            value: "",
            ...options,
          });
          response = NextResponse.next({
            request: {
              headers: request.headers,
            },
          });
          response.cookies.set({
            name,
            value: "",
            ...options,
          });
        },
      },
    }
  );

  const user = (await supabaseClient.auth.getUser()).data.user;

  return user;
}