findgift.js

var utility = ['pink bag','pink book','pink pen','pink shirt','pink shoe'];
var shop = [{'shopname':'aa shop','sell':'pink bag','price':30000,'distance':2},{'shopname':'bb shop','sell':'pink shirt','price':10000,'distance':3},{'shopname':'cc shop','sell':'pink shoe','price':15000,'distance':1},{'shopname':'dd shop','sell':'pink skirt','price':25000,'distance':0.5}]
var how ={'grab':5000,'own motor':2000};

var moneyihave = 50000;


var findperfectgift = async(moneyihave)=>{
    findshop(moneyihave,(whatshop,whattobuy,moneyileft)=>{
        findhow(moneyileft,(moneytopay,howigo)=>{
            moneyfinallytopay = moneyihave - moneytopay;
            bestoption = 'buy: '+whattobuy+' ,at: '+whatshop+' ,go by: '+ howigo+' all you need to pay: '+moneyfinallytopay;
            return bestoption;
        })
    });
    
}


var findshop=(moneyihave,callback)=>{
    var objectofchoice = new Object;
    shop.forEach(element => {
        if(element.price<moneyihave){
            objectofchoice[element.shopname]=element.price * element.distance;
        }
    });
    console.log(objectofchoice);
    var recentlowest = objectofchoice[Object.keys(objectofchoice)[0]];
    var shoplowest;
    for( const i in objectofchoice){
        if (recentlowest>objectofchoice[i]){
            recentlowest = objectofchoice[i];
            shoplowest = i;
        }
    };

    var whattobuy, moneythatleft;
    shop.forEach(element=>{
        if(element.shopname==shoplowest){
            whattobuy = element.sell;
            moneythatleft = moneyihave - element.price;
        }
    });
    callback(shoplowest,whattobuy,moneythatleft);
};
var findhow=(moneyileft,callback)=>{

    var recentlowest = how[Object.keys(how)[0]];
    var howlowest,moneythatifinallyleft;
    for(const i in how){
        if(recentlowest>how[i]){
            recentlowest = how[i];
            howlowest = i;
            moneythatifinallyleft = moneyileft - recentlowest;
        }
    }

    console.log(moneythatifinallyleft);
    callback(moneythatifinallyleft,howlowest);

};

findperfectgift(moneyihave).then(console.log(bestoption));