[...nextauth].ts

import NextAuth from "next-auth";
import Providers from "next-auth/providers";
import {fetch} from "utils/dataAccess";

const options = {
  providers: [
    Providers.Credentials({
      name: 'Credentials',
      authorize: async (credentials) => {
        const response = await fetch("/login_check", {
          method: "POST",
          body: JSON.stringify({
            username: credentials.username,
            password: credentials.password,
          }),
          headers: {
            "Accept": "application/json",
            "Content-Type": "application/json",
          },
        });

        return response.data;
      },
    })
  ],
  callbacks: {
    async jwt(token, user) {
      if (user) {
        token.user = user;
      }

      // token is valid
      if (new Date() < new Date(token.user.exp)) {
        return token;
      }

      // token has expired: force user to login again
      // todo implement refresh token
      return null;
    },
    async session(session, token) {
      if (token) {
        session.token = token;
      }
      if (token.user) {
        session.user = token.user;
      }

      return session;
    },
  },
  pages: {
    signIn: '/login',
    error: '/login',
    newUser: '/register',
  },
}

export default (req, res) => NextAuth(req, res, options);