/*  EXPRESS SETUP  */

const express = require('express');
const app = express();

const bodyParser = require('body-parser');
app.use(bodyParser.urlencoded({
    extended: true
}));

const mongoose = require('mongoose');
mongoose.connect('mongodb://localhost/MyDatabase');

const Schema = mongoose.Schema;
const UserDetail = new Schema({
    username: String,
    password: String
});
const UserDetails = mongoose.model('userInfo', UserDetail, 'userInfo');


const passport = require('passport');


app.use(require('express-session')({
    secret: 'keyboard cat',
    resave: false,
    saveUninitialized: false
}));
app.use(passport.initialize());
app.use(passport.session());

//We have to store the data in to req.session.passport={} object
passport.serializeUser(function(user, done) {
  done(null, user.id);
});

//We always need to deserilaize and validate the user
passport.deserializeUser(function(id, done) {
  User.findById(id, function (err, user) {
    done(err, user);
  });
});


const LocalStrategy = require('passport-local').Strategy;
//There are lot of strategies are there so we can use any of the strategy for an example Oauth, twitter, facebook login mechanisams
passport.use(new LocalStrategy(
    function (username, password, done) {
        UserDetails.findOne({
            username: username
        }, function (err, user) {
            if (err) {
                return done(err);
            }

            if (!user) {
                return done(null, false);
            }

            if (user.password != password) {
                return done(null, false);
            }
            return done(null, user);
        });
    }
));

app.get('/',
    passport.authenticate('local', {
        failureRedirect: '/error'
    }),
    function (req, res) {
        res.redirect('/success?username=' + req.user.username);
    });


app.post('/',
    passport.authenticate('local', {
        failureRedirect: '/error'
    }),
    function (req, res) {
        res.redirect('/success?username=' + req.user.username);
    });

app.get('/success', (req, res) => res.send("Welcome " + req.query.username + "!!"));
app.get('/error', (req, res) => res.send("error logging in"));

passport.serializeUser(function (user, cb) {
    cb(null, user.id);
});

passport.deserializeUser(function (id, cb) {
    User.findById(id, function (err, user) {
        cb(err, user);
    });
});



app.get('/', (req, res) => res.sendFile('auth.html', {
    root: __dirname
}));



const port = process.env.PORT || 3000;
app.listen(port, () => console.log('App listening on port ' + port));