app.js

if(process.env.NODE_ENV!="production") { //not to deploy .env file while uploading to git
  require('dotenv').config();
}

const express =require("express");
const app=express();
const mongoose=require("mongoose");
const listing=require("./models/listing.js");
const path=require("path");
const methodOverride=require("method-override");
const ejsMate=require("ejs-mate");
const reviews=require("./models/reviews.js");
const asyncwrap=require("./utils/error.js");
const expressError=require("./utils/expressError.js");
const multer  = require('multer')
const {storage}=require("./cloudConfig.js")
const upload = multer({storage});  //destination =cloud storage
const cookieparser=require("cookie-parser");
const session=require("express-session");
const MongoStore = require('connect-mongo'); //to connect mongo to cloud database
const flash = require("connect-flash");
const passport=require("passport");
const localStrategy=require("passport-local");
const User=require("./models/user.js");
const { isLoggedIn } = require("./middlewares/middleware.js");
const {saveRedirectUrl}=require("./middlewares/middleware.js");
const {isOwner,isAuthor}=require("./middlewares/middleware.js");
const {index, newpost, createpost, editpost, saveEditpost, deletepost, showPost, signup}=require("./controllers/listing.js");
const { deleteReview, reviewPost } = require("./controllers/reviews.js");

app.use(flash());
app.use(cookieparser());
app.set("view engine","ejs");
app.set("views", path.join(__dirname, "views"));  //to run file from everywhere
app.use(express.urlencoded({extended:true}));  //for parsing the data
app.use(methodOverride('_method'));
app.engine('ejs', ejsMate); //to create ejs template for every page ex. footer,navbar
app.use(express.static(path.join(__dirname, "/public"))); //to use files in public folder

const dbUrl=process.env.ATLAS_DB_TOKEN;

main().catch(err => console.log(err));

async function main() {
  await mongoose.connect(dbUrl);
  console.log("database connected");
}
const store =MongoStore.create({
  mongoUrl:dbUrl,
  crypto:{
    secret:process.env.SECRET
  },
  touchAfter:24*3600,
});//to store info of session even after refresh


store.on("error", ()=>{
  console.log("error in mongo session store", err);
})
const sessionOptions={
  store,
  secret:process.env.SECRET,
  resave:false,
  saveUninitialized: true,
  cookie:{
    expires:Date.now() +7*24*60*60*1000,
    maxAge:7*24*60*60*1000,
    httpOnly : true,
  },
};



app.use(session(sessionOptions)); //used to save users login in ame browser always, has session id

app.use(passport.initialize());
app.use(passport.session()); //to identify users from page to page
passport.use(new localStrategy(User.authenticate()));
passport.serializeUser(User.serializeUser()); //used in login
passport.deserializeUser(User.deserializeUser()); //used for logout

//flash middleware
app.use((req, res, next) => {
  res.locals.success = req.flash('success');
  res.locals.error = req.flash('error');
  res.locals.currUser=req.user; //storecurrent session user info in currUser
  next();
});


  //API
  //signup
  app.get("/signup",asyncwrap (async(req,res) => {
  res.render("signup.ejs");
  }));

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

  // Check for missing fields
  if (!username || !password) {
    req.flash('error', 'Username and password are required');
    return res.redirect('/signup');
  }
  try {
    const newUser = new User({ username, email });
    await User.register(newUser, password); 
    req.login(newUser, (err) => {
      req.flash('success', 'Welcome! You have successfully signed up.');
      res.redirect('/listing');
    });
  } catch (err) {
    req.flash('error', err.message);
    res.redirect('/signup');
  }
}));

//login
app.route("/login")
.get( asyncwrap ((req,res) =>{
  res.render("login.ejs");
}))
.post(
  saveRedirectUrl,
  passport.authenticate("local", {
  failureRedirect: "/login",
  failureFlash: true
}), (req, res) => {
  req.flash("success", "Welcome back!");
  let redirect=res.locals.redirectUrl||"/listing";  
  res.redirect(redirect); // Redirect to a route that will display the message
});
  
  //logout
  app.get("/logout",(req,res,next) =>{
    req.logout((err) =>{
      if(err) {
       return  next(err);
      }
      else{
        req.flash("success","Logged out successfuly");
        res.redirect("/listing");
      }
    })
})

//create new listing
app.get("/new",isLoggedIn, asyncwrap(newpost));

//index route
app.get("/listing",asyncwrap(index));

//create post
app.post("/listing",upload.single('listing[image]'),isLoggedIn,asyncwrap(createpost));

//edit the listings
app.get("/listing/:id/edit",isLoggedIn,isOwner,asyncwrap(editpost));

//save the updated listing
app.put('/listing/:id', isLoggedIn,isOwner,upload.single('listing[image]'), asyncwrap(saveEditpost));

//delete listing
app.delete("/listing/:id",isLoggedIn,isOwner,asyncwrap(deletepost));

//show listing in detail
app.get('/listing/:id', asyncwrap(showPost));

//review submit route
app.post("/listing/:id/review", isLoggedIn, asyncwrap(reviewPost));
 
//delete reviews
app.delete("/listing/:id/review/:rid",isLoggedIn,isAuthor,asyncwrap(deleteReview));

//for all invalid route error
app.use("*",(req,res,next) =>{
next(new expressError(404,"page not found"));
})

  //error handling
  app.use((err,req,res,next) =>{
  
  let{status=500,msg="Something went wrong"}=err;
  res.render("error.ejs",{msg,status});
})

app.listen(8080, () =>{
    console.log("server is listening");
});