app.js

require('dotenv').config()
const express = require("express");
const bodyParser = require("body-parser");
const ejs = require("ejs");
const mongoose = require("mongoose");
const session = require('express-session');
const passport = require('passport');
const passportLocalMonngoose = require('passport-local-mongoose');
const GoogleStrategy = require('passport-google-oauth20').Strategy;
const findOrCreate = require('mongoose-findorcreate');

const app = express();

app.use(express.static("public"));
app.set('view engine', 'ejs');
app.use(bodyParser.urlencoded({extended:true}));

app.use(session({
    secret: "Our little secret.",
    resave: false,
    saveUninitialized: false
}));  

app.use(passport.initialize());
app.use(passport.session())

mongoose.connect("mongodb://127.0.0.1:27017/userDB", {useNewUrlParser: true});

const userSchema = new mongoose.Schema({
    email : String,
    password : String,
    googleId : String,
    secrets : [String]
})
userSchema.plugin(passportLocalMonngoose);
userSchema.plugin(findOrCreate);
// console.log(process.env.SECRET);

const User = new mongoose.model("User", userSchema);
passport.use(User.createStrategy());

// passport.serializeUser(User.serializeUser());
// passport.deserializeUser(User.deserializeUser());

passport.serializeUser((User, done) => {
    done(null, User.id);
 });
 
 passport.deserializeUser(async (id, done) => {
   const USER = await User.findById(id);
   done(null, USER);
 });

try{
    passport.use(new GoogleStrategy({
        clientID: process.env.GOOGLE_CLIENT_ID,
        clientSecret: process.env.GOOGLE_CLIENT_SECRET,
        callbackURL: 'http://127.0.0.1:3000/auth/google/secrets',
      },
      async function(accessToken, refreshToken, profile, cb) {
        // console.log(profile);
        await User.findOrCreate({ googleId: profile.id }, function (err, user) {
          return cb(err, user);
        });
      }
    ));
}
catch{
    console.log(err);
}

app.get("/",function(req,res){
    res.render("home");
});

app.get("/auth/google",
    passport.authenticate('google', { scope: ['profile'] })
)

app.get('/auth/google/secrets', 
  passport.authenticate('google', { failureRedirect: '/login' }),
  function(req, res) {
    // Successful authentication, redirect home.
    res.redirect('/secrets');
});

app.get("/login",function(req,res){
    res.render("login");
});

app.get("/register",function(req,res){
    res.render("register");
}); 

app.get("/logout",function(req,res){
    req.logout(function(err) {
        if (err) { return next(err); }
        res.redirect('/');
      });
});

app.get("/secrets",async function(req,res){
    const foundUser = await User.find(req.user._id).exec();
    console.log(foundUser);
    try{
        res.render("secrets", {userWithSecrets : foundUser})
    } catch(err){
        console.log(err);
    }
});

app.get("/submit", function( req, res ){
    if(req.isAuthenticated()){
        res.render("submit");
        console.log(req.user);
    } else {
        res.redirect("/login");
    }
});

app.post("/submit", async function (req, res) {
    const submittedSecret = req.body.secret;

    console.log(req.user);
    console.log(submittedSecret);

    const foundUser =await User.findById(req.user._id);
    if(foundUser){
        foundUser.secrets.push(submittedSecret);
        await foundUser.save();
        res.redirect("/secrets");
    }
})

app.post("/register", function(req,res){
    User.register({username: req.body.username}, req.body.password, function(err,user){
        if (err){
            console.log(err);
            res.redirect("/register");
        }
        else{
            passport.authenticate("local")(req,res,function() {
              res.redirect("/secrets");  
            })
        }
    })
});

app.post("/login", async function(req,res){

    const user = new User({
        username : req.body.username,
        password : req.body.password

    });

    req.login(user, function(err){
        if (err){
            console.log(err);
        }else{
            passport.authenticate("local")(req,res,function() {
                res.redirect("/secrets");  
              })
        }
    })
});

app.listen(3000, function(){
    console.log("Server started on 3000");
})