const mongoose = require("mongoose")
const bcrypt = require('bcryptjs')
const {nanoid} = require('nanoid')

const userResponse = u => ({_id: u._id, email: u.email, isVerified: u.isVerified, noteList: u.noteList})

const userSchema = new mongoose.Schema({
  email: {
    type: String,
    trim: true,
    lowercase: true,
    unique: true,
    required: true,
    minlength: 6,
    maxlength: 255,
    validate(value) {
      if (!/^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(value)) {
        throw new Error('Wrong email address')
      }
    }
  },
  password: {
    type: String,
    required: true,
    minlength: 6,
    maxlength: 1024,
  },
  isVerified: {
    type: Boolean,
    default: false,
  },
  verificationKey: {
    type: String,
    default: () => nanoid(6),
  },
  noteList: {
    type: mongoose.Schema.Types.ObjectId,
    ref: "NoteList",
    required: true,
  },
  created_at: {type: Date, default: Date.now},
  updated_at: {type: Date, default: Date.now}
})

userSchema.statics.findByCredentials = async function (email, password){
  const user = await User.findOne({email})

  if (!user) {
    throw new Error('Unable to login')
  }

  const isMatch = await bcrypt.compare(password, user.password)

  if (!isMatch) {
    throw new Error('Unable to login')
  }

  return userResponse(user)
}

userSchema.statics.getVerificationKey = async function (email){
  const {verificationKey: key} = await User.findOne({email})

  if (!key) {
    throw new Error('Could not verify user')
  }

  return key
}

userSchema.statics.verifyUser = async function (_id, key){
  const user = await User.findOneAndUpdate({_id, verificationKey: key}, {isVerified: true, verificationKey: nanoid(10)}, {new: true})

  if (!user) {
    throw new Error('Could not verify user')
  }

  return userResponse(user)
}

userSchema.statics.state = async function (_id){
  const user = await User.findOne({_id})

  if (!user) {
    return {isLoggedIn: false}
  } else if (!user.isVerified) {
    return {isVerified: false}
  }

  return {}
}


userSchema.pre('save', async function(next){
  const user = this;

  if (user.isModified('password')) {
    user.password = await bcrypt.hash(user.password, 8);
  }

  next()
})

const User = mongoose.models.User || mongoose.model('User', userSchema)

export default User