//imports
const app = require('express')(),
      session = require('express-session'),
      bodyParser = require('body-parser'),
      jwt = require('jsonwebtoken'),
      passport = require('passport'),
      {Strategy, ExtractJwt} = require('passport-jwt'),
      LocalStrategy = require('passport-local'),
      FacebookStrategy = require('passport-facebook'),
      TwitterStrategy  = require('passport-twitter'),
      GoogleStrategy = require('passport-google-oauth').OAuth2Strategy,
      {fb, twitter, google} = require('./authInfo'),
      {hashSync,compareSync, genSaltSync} = require('bcryptjs'),
      mongoose = require('mongoose'),
      {connection, Schema}=mongoose





//db config
mongoose.Promise=global.Promise
mongoose.connect('mongodb://localhost/test')
connection.on('error', console.error.bind(console, 'connection error:'));
connection.once('open', ()=> console.log('connected to DB!'))


//model setup
const userSchema = new Schema({username: String, password: String})
userSchema.pre('save', function(next){
  this.password=hashSync(this.password, genSaltSync(10))
  next()
})
const User = mongoose.model('User', userSchema)


//global mids
app.use(bodyParser.urlencoded({ extended: true }))
app.use(bodyParser.json())
app.use(session({secret:'secret',resave: true,saveUninitialized: true}))
app.use(passport.initialize())
app.use(passport.session())




//strategies
const userLogin = new LocalStrategy((username, password, done)=>{
  User.findOne({username})
    .then(userFromDB=>{
      compareSync(password, userFromDB.password) ? done(null, userFromDB) : done(null, false)
    }).catch(e=>done(e))
})


const jwtOptions={
  jwtFromRequest: ExtractJwt.fromHeader("authorization"),
  secretOrKey: 'secret'
}
const jwtLogin = new Strategy(jwtOptions, (fromPassport, done)=>{
  User.findById(fromPassport._id)
    .then(userFromDB=>{userFromDB ? done(null, userFromDB) : done(null, false)
    }).catch(e=>done(e))
})


const fbLogin = new FacebookStrategy(fb, (accessToken, refreshToken, profile, done)=> done(null, profile))
const twitterLogin = new TwitterStrategy(twitter, (token, tokenSecret, profile, done)=>done(null, profile))
const googleLogin = new GoogleStrategy(google, (accessToken, refreshToken, profile, done)=>done(null, profile))


passport.use('local',userLogin)
passport.use('jwt',jwtLogin)
passport.use('facebook',fbLogin)
passport.use('twitter',twitterLogin)
passport.use('google',googleLogin)
passport.serializeUser((user, done)=>done(null, user.id))
passport.deserializeUser((id, done)=>User.findById(id).then(userFromDB=>done(user)))


const signToken = _id=>jwt.sign({_id}, "secret" )

app.get('/', passport.authenticate('jwt', {session:false}), (req,res)=> res.send('Protected Resource'))

app.get('/auth/facebook', passport.authenticate('facebook'))
app.get('/auth/facebook/callback', passport.authenticate('facebook', {session:false}), (req, res)=> res.send(req.user))

app.get('/auth/google', passport.authenticate('google',  { scope : ['profile', 'email'] } ))
app.get('/auth/google/callback', passport.authenticate('google'), (req, res)=> res.send(req.user))

app.get('/auth/twitter', passport.authenticate('twitter'))
app.get('/auth/twitter/callback', passport.authenticate('twitter'), (req, res)=> res.send(req.user))



app.post('/signup', (req, res)=>{
  const {username, password} = req.body
  User.findOne({username})
    .then(userFromDB=>{
      if(userFromDB) res.status(422).send('Username is already use')
      else if (!username || !password) res.status(422).send('Must provide an username and password')
      else new User(req.body).save().then(savedUser=>res.json({token: signToken(savedUser._id)}))
    }).catch(e=>res.status(400).send(e.message))
})



app.post('/signin', passport.authenticate('local', {session:false}), (req,res)=>{
  res.json({token: signToken(req.user._id)})
})


app.listen(process.env.PORT, console.log(`on ${process.env.PORT}`))