sorting objects

Homework13_2

let collection = [
    {
        name: 'John',
        age: 18,
        friendsCount: 22
    },
    {
        name: 'Eve',
        age: 17,
        friendsCount: 14
    },
    {
        name: 'Helen',
        age: 28,
        friendsCount: 48
    }
];
let collection1 = [
    {
        name: 'Max',
        age: 22,
        friendsCount: 32
    }
    ];
function compare(a, b, property) {
    if (a[property] < b[property]) {
        return -1;
    } else if (a[property] > b[property]) {
        return 1;
    }
    return 0;
}

function makeCondition(propertyName, direction) {
    return function (a, b) {
        if (direction === 'desc') {
            let c;
            c = a;
            a = b;
            b = c;
        }
        return compare(a, b, propertyName);
    }
}
function applyConditions(conditions) {
    return function (a,b) {
        let result = 0;
        let i = 0;
        do {
            result = conditions[i++](a,b)
        } while (result === 0 && i < conditions.length);
        console.log(result)
        return result;
    }
}
function sort(...collections) {
    let collection = [].concat(...collections);
    let conditions = [];
    function part(propertyName, direction = 'asc') {
        if(!propertyName || !direction){
            return collection.sort(applyConditions(conditions))
        }
        conditions.push(makeCondition(propertyName, direction));
        return part;
    }
    return part;
}
let result = sort(collection,collection1)('salary','desc')('name','desc')('age')();
console.log(result);