middleware.js

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

module.exports.isLoggedIn=(req,res,next)=>{
   
     if(!req.isAuthenticated()){
      //saving redirectUrl path=>login=>path(redirect url)
      req.session.redirectUrl=req.originalUrl;
        req.flash("error","you must be logged in to create listing!");
       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.currUser._id)){
     req.flash("error","You are not the owner of this listing");
     return res.redirect(`/listings/${id}`);
    }
    next();
};

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

module.exports.validateReview=(req,res,next)=>{

    let {error}=reviewSchema.validate(req.body);   
    if(error){
    let errMsg=error.details.map((el)=>el.message).join(",");
        throw new ExpressError(400,errMsg);
    }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.currUser._id)){
     req.flash("error","You are not the author of this review");
     return res.redirect(`/listings/${id}`);
    }
    next();
};