var validateUser =  function(userName, password, callback){

    const MongoClient = require('mongodb').MongoClient;

    // replace the uri string with your connection string.
    const uri = "mongodb+srv://CarlosHz:BlackjackSeng513@blackjack-2j9ms.mongodb.net/test?retryWrites=true";
    MongoClient.connect(uri, function(err, client) {
        if(err) {
            console.log('Error occurred while connecting to MongoDB Atlas...\n',err.stack);
        }else{
            console.log('Connected...');
            const db = client.db("Blackjack");
            const collection = db.collection("Users");
            collection.findOne({username: userName}, (function(err, result){
                if(err){
                    console.log("error in find");
                }else if(result != null){
                    console.log("success find function");
                    console.log(result.username + " " + result.password + " was found");
                    if(result.username === userName && result.password === password){
                        console.log("returning true");
                        return callback(true);
                    }else{
                        console.log("returning false");
                        return callback(false);
                    }
                }else{
                    console.log("user does not exists");
                    console.log("returning false");
                    return callback(false);
                }
            }));
            client.close();
            //collection.insertOne( {username: "poop", password: "wtfisthis"});
            //var query = { username: "poop" };
            //var newval = { $set: {balance: 500 }};
            //collection.updateOne(query, newval, function(err, res){
            //  if(err){
            //      console.log("error");
            //  }else{
            //      console.log("success");
            //  }
                // perform actions on the collection object
                //client.close();
            }
        });
}