middleware.js

const Listing = require("./models/listing.js");
const Review = require("./models/review.js");
const ExpressError = require('./utils/expressErrors.js');
const { listingSchema , reviewSchema} = require('./schema.js');

module.exports.isLoggedIn = (req,res,next) =>{
     if(!req.isAuthenticated()){

    req.session.redirectUrl = req.originalUrl;
    req.flash('error', 'You must be signed in first!');
    return res.redirect("/login");
  }
  next();
}

module.exports.saveRedirectUrl = (req, res, next) => {
    if(req.session.redirectUrl){
        res.locals.redirectUrl = req.session.redirectUrl;
    }
    next();
}

module.exports.isOwner = async (req, res , next) =>{
   let {id} = req.params;
   let listing = await Listing.findById(id);
    if(!listing.owner.equals(res.locals.currentUser._id)){
        req.flash('error', 'You do not have permission to do that!');
        return res.redirect(`/listings/${id}`);
    }
    next();
}

module.exports.validateListing = (req, res, next) => {
    let { error } = listingSchema.validate(req.body);
    if(error){
        let errorMessage = error.details.map(el => el.message).join(', ');
        throw new ExpressError(errorMessage, 400);
    }
    else{
        next();
    }
}

module.exports.validateReview = (req, res, next) => {
    let { error } = reviewSchema.validate(req.body);
    if(error){
        let errorMessage = error.details.map(el => el.message).join(', ');
        throw new ExpressError(errorMessage, 400);
    }
    else{
        next();
    }
}

module.exports.isReviewAuthor = async (req, res , next) =>{
   let { id ,reviewId} = req.params;

   let review = await Review.findById(reviewId);
    if(!review.author.equals(res.locals.currentUser._id)){
        req.flash('error', 'You do not have permission to do that!');
        return res.redirect(`/listings/${id}`);
    }
  next();
};