'use strict'
const express = require('express')
const app = express()
const mongoose = require('mongoose')
const Schema = mongoose.Schema
const database = 'mongodb://' + process.env.mongousr + ':' + process.env.mongopwd + '@mongo:27017/test'
const today = new Date()
var counter = 0
const Prometheus = require('prom-client')
const fs = require('file-system')
const marked = require('marked')
const jwt = require('jsonwebtoken')
const bodyParser= require('body-parser')
const secret = 'wowmuchsecretveryhiddenwow' 
const successUrl = 'yay.html'
const failureUrl = 'nay.html'
const cookieParser = require('cookie-parser')
const os = require('os')

app.use(cookieParser())

app.use(express.static('html'))

// const morgan = require('morgan')
// // use morgan to log requests to the console
// app.use(morgan('dev'))

// global controller
// app.get('/*',function(req,res,next){
//   res.header.token = 'sample-token'
//   next() // http://expressjs.com/guide.html#passing-route control
// })

// a middleware with no mount path gets executed for every request to the app
// app.use(function(req, res, next) {
//   res.setHeader('charset', 'utf-8')
//   next()
// })

// setting CORS headers
app.all('/', function(req, res, next) {
  res.header("Access-Control-Allow-Origin", "*")
  res.header("Access-Control-Allow-Headers", "X-Requested-With")
  next()
})

// database connection (with retries)
const options = {
  autoIndex: false, // Don't build indexes
  reconnectTries:30, // Retry up to 30 times
  reconnectInterval: 500, // Reconnect every 500ms
  poolSize: 10, // Maintain up to 10 socket connections
  // If not connected, return errors immediately rather than waiting for reconnect
  bufferMaxEntries: 0,
  useNewUrlParser: true
}

const connectWithRetry = () => {
  console.log('MongoDB connection with retry')
  mongoose.connect(database, options).then(()=>{
    console.log('MongoDB is connected')
  }).catch(err=>{
    console.log('MongoDB connection unsuccessful, retry after 5 seconds.')
    setTimeout(connectWithRetry, 5000)
  })
}

const libCounter = new Prometheus.Counter({
  name: 'lib_invocation_count',
  help: 'A simple counter for app access during runtime created with prometheus nodejs library'
})

const libUptime = new Prometheus.Counter({
  name: 'lib_upTime',
  help: 'uptime A counter of the application\'s uptime in seconds created with prometheus nodejs library.'
})

console.log('mongousr: ', process.env.mongousr)
console.log('mongopwd: ', process.env.mongopwd)

// Prometheus Default Metrics collector
const collectDefaultMetrics = Prometheus.collectDefaultMetrics
// Probe every 5th second.
collectDefaultMetrics({ timeout: 5000 })

// new schema model object based on the structure of what I want to put on MongoDB collection
var testSchema = new Schema({
  thingies: {
    type: String
  }
},{
  collection: 'test'
})

// new object that will hold the data using model structure made above
var thingies = mongoose.model('thingieName', testSchema)

// Default message for testing
app.get('/', (req, res, next)=>{
  res.json([{message:'yes, your nodejs app is really running'}])
  // res.send('Oh hay' + '\n')
  counter++ // for prometheus invocation_count metric
  libCounter.inc() // for prometheus lib_invocation_count metric
  console.log('Hello, I\'m inside endpoint \'/\'')
  console.log('HTTP headers below:')
  console.log(req.headers)
  console.log('Cookies: ', req.cookies)
  console.log('Cookies: ', res.cookies)
  console.log('\x1b[35m', 'HOSTNAME below:')
  console.log(os.hostname())
  next()
})

// cookie experiments endpoint
app.get('/cookie', function(req, res, next) {
  // res.cookie('cookiename', 'cookievalue')
  // res.setHeader('Set-Cookie', 'cookiename=cookievalue HttpOnly')
  // res.cookie('foo3', 'bar3', { maxAge: 900000, httpOnly: true })
  res.json({message: 'I am inside endpoint /cookie'})
  res.json(JSON.stringify(req.headers))
  res.end()
  console.log('\x1b[35m', 'Cookies: ', req.cookies)
  console.log('\x1b[35m', 'req.cookies.token below:')
  console.log(req.cookies.token)
})

// Clear cookies
app.get('/clear', function(req, res) {
  res.clearCookie('token')
  res.clearCookie('cookiename')
  res.clearCookie('Authorization')
  res.clearCookie('foo3')
  console.log(req.cookies)
  res.status(200).send('Cookies cleared')
})

// Test endpoint for md files rendering
app.get('/test', function(req, res) {
  var path = '/app/README.md'
  var file = fs.readFileSync(path, 'utf8')
  res.send(marked(file.toString()))
})

// Prometheus metrics endpoint - Library
app.get('/metrics', function(req, res){
  libUptime.inc(Math.floor(process.uptime()))
  res.set('Content-Type', Prometheus.register.contentType)
  res.end(Prometheus.register.metrics())
  libUptime.reset()
})

// Prometheus metrics endpoint - Handmade
app.get('/metrics2', function(req, res){
  var now = new Date()
  var passedTime = now - today
  res.writeHead(200, {'Content-Type':'text/plain'})
  res.write('# HELP uptime A counter of the application\'s uptime in millisenconds.' + '\n')
  res.write('# TYPE uptime counter' + '\n')
  res.write('uptime ' + passedTime + '\n')
  res.write('# HELP invocation_count A simple counter for app access during runtime' + '\n')
  res.write('# TYPE invocation_count counter'+ '\n')
  res.write('invocation_count ' + counter + '\n')
  res.end()
})

// JWT generation
app.use(bodyParser.urlencoded({ extended: false }))

app.post('/token', function(req, res) {

  const claims_power = { 
    username: req.body.username,
    password: req.body.password,
    subject: 'power#1234',
    issuer: 'http://youcantrustme.io',
    scope: 'admin' 
  }
  
  const claims_user = { 
    username: req.body.username,
    password: req.body.password,
    subject: 'normal_user',
    issuer: 'http://youcantrustme.io',
    scope: 'user' 
  }

  switch(req.body.username) {
      case 'user1':
      if (req.body.password === 'pass1') {
          let token = jwt.sign(claims_user, secret)
          res.cookie('token', token)
          // res.setHeader('Set-Cookie', 'token=' + token + ' HttpOnly')
          // res.setHeader('Set-Cookie', 'Authorization=Bearer ' + token + ' HttpOnly')
          console.log('JWT Token: ' + token)
          console.log(jwt.decode(token))
          res.redirect(successUrl)
      } else {
          res.redirect(failureUrl)
      }
      break
      case 'power':
      if (req.body.password === 'weak') {
          let token = jwt.sign(claims_power, secret)
          res.cookie('token', token)
          // res.setHeader('Set-Cookie', 'token=' + token + ' HttpOnly')
          console.log('JWT Token: ' + token)
          console.log(jwt.decode(token))
          res.redirect(successUrl)
      } else {
      res.redirect(failureUrl)
      }
      break
      default:
      res.status(500).send('User not found')
  } 
  console.log('http headers below:')
  console.log(req.headers)
})


// Restricted route root
const restrictedRoutes = express.Router()
app.use('/restricted', restrictedRoutes)

// setting CORS headers
restrictedRoutes.all('/', function(req, res, next) {
  res.header("Access-Control-Allow-Origin", "*")
  res.header("Access-Control-Allow-Headers", "X-Requested-With")
  next()
})

restrictedRoutes.use(function (req, res, next) {
  res.setHeader('HOSTNAME', os.hostname())
  if (req.cookies.token) {
    jwt.verify(req.cookies.token, secret, function (err, decoded) {
      if (err) {
        res.json({ message: 'invalid token' })
      } else {
        req.decoded = decoded
        console.log(decoded)
        console.log(req.decoded['scope'])
        switch(req.decoded['scope']) {
          case 'user':
          res.status(200).json([{message: 'Need ADMIN scope to access the good stuff'}])
          break
          case 'admin':
          next()
          break
          default:
          res.status(401).json([{message: 'Not authorized'}])
        }
      }
    })
  } else {
    res.status(500).json({ message: 'no token found' })
  }
})

// Restricted endpoint
restrictedRoutes.get('/', (req, res) => {
  res.status(200).json([{secret:'You have access to restricted contents!'}])
  console.log(JSON.stringify({secret:'You have access to restricted contents!'}))
})

// // Restricted route root stupid
// const restrictedRoutes = express.Router()
// app.use('/restricted', restrictedRoutes)

// restrictedRoutes.use( function(req, res, next){
//   let sentToken = req.headers['token']
//   console.log('hello there, do not mind me.')
//   console.log('next line will show the JWT token:')
//   console.log(sentToken)
//   console.log('okay, so, next line will show the decoded JWT token:')
//   let decodedToken = jwt.decode(sentToken)
//   console.log(decodedToken)
//   console.log('yay, so now I am going to verify it and show again the decoded token if successful.')
//   console.log('if NOT successful I will not let you see the secret message')
//   console.log('here we go...')
//   let verifiedToken = jwt.verify(sentToken, secret)
//   console.log(verifiedToken)
//   if (verifiedToken) {
//     console.log('success! secret message will be shown.')
//     next()
//   } else {
//     res.status(401).json({message: 'nope, you are not authorized'})
//   }
// })

// Restricted route root test (KISS)
const router = express.Router()
app.use('/api', router)

router.use( function(req, res, next){
  console.log('yo, this should always be called whenever /api or anything inside is called')
  next()
})

// Restricted route endpoint test (KISS)
router.get('/inside', (req, res) => {
  console.log('I am inside /api, hopefully')
  res.status(200).json({message: 'it worked'})
})

// JWT decode test
app.get('/decode', function(req, res){
  let sentToken = req.headers['token']
  if (sentToken) {
    var decode = jwt.verify(sentToken, secret)
    console.log(decode)
    res.status(200).send('success')
  }
})

// Mongo query
app.get('/info', function(req, res){
  thingies.find({}).then(function (thingies) {
    res.json(thingies)
  })
})


// Mongo insert
app.post('/info/add/:name', function(req, res){
  var item = {thingies: req.params.name}
  var data = new thingies(item)
  data.save()
  res.send('thingie ' + req.params.name + ' added to database' + '\n')
})

connectWithRetry()

app.listen(3001, () => {
  console.log('Server running on port 3001')
  console.log('process.env.PORT: ' + process.env.PORT)
})