const router = require("express").Router();
const mongoose = require("mongoose");
const User = require("../models/Users");
const bcrypt = require("bcrypt");
const jwt = require("jsonwebtoken");

// Route 1: create new user at /api/createuser
router.post("/createuser", async (req, res) => {
  try {
    console.log(req.body);
    const salt = await bcrypt.genSaltSync(10);
    const hash = await bcrypt.hashSync(req.body.password, salt);
    password = hash;
    const user = new User({
      name: req.body.name,
      email: req.body.email,
      password: password,
    });
    user
      .save()
      .then(() => {
        res.json({ message: "User created successfully" });
      })
      .catch((err) => {
        res.json({ message: "Error: " + err });
      });
    console.log(password);
  } catch (err) {
    res.json({ message: err });
  }
});

// Route 2: Login user at /api/login
router.post("/login", async (req, res) => {
  try {
    console.log("login endpoint triggered");
    const user = await User.findOne({ email: req.body.email });
    if (!user) {
      res.json({ message: "User does not exist" });
    }
    const passwordIsValid = await bcrypt.compare(
      req.body.password,
      user.password
    );
    if (!passwordIsValid) {
      res.json({ message: "Invalid password" });
    } else {
      const data = {
        id: user._id,
      };
      const token = await jwt.sign(data, process.env.SECRET);
      res.json(token);
    }
  } catch (error) {
    res.json({ message: error });
  }
});

module.exports = router;

Whenever I am testing the login endpoint, my app crashes if i try to put incorrect password or unregistered email. It says Error [ERR_HTTP_HEADERS_SENT]: Cannot set headers after they are sent to the client I have only sent one response to the client even then it is showing this error. In the terminal, it is showing error at catch block of login endpoint. Can anyone look into it and tell me why am i getting this error.