models/User.js

import mongoose from 'mongoose'

const userSchema = new mongoose.Schema({
  name: { type: String, required: true },
  email: { type: String, required: true, unique: true },
  password: { type: String, required: true },
  role: { type: String, enum: ['user', 'admin'], default: 'user' },
  createdAt: { type: Date, default: Date.now }
})

userSchema.set('toJSON', {
  transform: (document, returnedObject) => {
    returnedObject.id = returnedObject._id.toString()
    delete returnedObject._id
    delete returnedObject.__v
    delete returnedObject.password
  }
})

export default mongoose.models.User || mongoose.model('User', userSchema)