const fs = require('fs')
const path = require('path')
const express = require('express')
const compression = require('compression')
const bodyParser = require('body-parser')
const jwt = require('jsonwebtoken')

// Allow CORS
const origin = '*'
const app = express()

app.use(bodyParser.json())
app.use((req, res, next) => {
  res.header('Access-Control-Allow-Origin', origin)
  res.header('Access-Control-Allow-Headers', 'Origin, X-Requested-With, Content-Type, Accept')
  next()
})

// API
const secret = 'secret'
const generateToken = (user) => jwt.sign(user, secret)

app.post('/signup', async (req, res) => {
  const { email, password } = req.body

  if (email === '' || password === '') {
    res.status('400').send('Empty fields')
    return
  }

  const exist = '' // check if user exist in your db
  const id = '' // generate an id

  if (exist) {
    res.status('409').send('Try again')
  } else {
    // save your user
    const token = generateToken({ email, user: id })
    res.send({ exist: false, token, id, email })
  }

})

app.post('/login', async (req, res) => {
  const { email, password } = req.body

  const id = '' // find id of the user
  const storedPassword = '' // get pass hash
  const valid = '' // compare
  const token = generateToken({ email, user: id })

  if (valid) {
    res.send({ exist: true, token, id, email })
  } else {
    res.status('409').send('Wrong password/username')
  }

})

app.post('/token', async (req, res) => {
  const { token } = req.body
  jwt.verify(token, secret, (err, d) => {
    err
      ? res.status('400').send('Try again')
      : res.send({ exist: true, token, id: d.id, email: d.email })
  })
})

// Static
app.use(compression())
app.use('/', express.static(__dirname + '/public', { maxAge: 86400000 }));
app.get('*', (req, res) => res.sendFile(__dirname + '/public/index.html'))

// Run server
app.listen(process.env.PORT || 5000)