js-advance-08-furniture

function solve() {
    const genBtn = document.querySelector('#exercise button');
    const buyBtn = document.querySelector("#exercise > button:nth-child(6)");
    genBtn.addEventListener('click', getData);
    buyBtn.addEventListener('click', procesData);
    const tbody = document.querySelector("#exercise > div > div > div > div > table > tbody");
    const result = document.querySelector("#exercise > textarea:nth-child(5)");
    let totalPrice = 0;
    let avgDecFactor = 0;
    let averages = [];
    let goodsBuyed = [];

    function genAttrElement(type, attr, content) {
        let item = document.createElement(type);
        item.setAttribute(attr, content);
        return item;
    }

    function genericElement(typeEl, content) {
        let htmlElement = document.createElement(typeEl);
        if (typeof content === 'string' || typeof content === 'number') {
            htmlElement.innerHTML = content;
        }
        if (typeof content === 'object') {
            htmlElement.appendChild(content);
        }
        return htmlElement;
    }

    function addItem(par, child) {
        return par.appendChild(child);
    }

    function getData() {
        let arr = JSON.parse(document.querySelector("#exercise > textarea:nth-child(2)").value);
        arr.map(function (e) {
                let name = genericElement('p', e['name']);
                let img = genAttrElement('img', 'src', e['img']);
                let price = genericElement('p', e['price']);
                let decFactor = genericElement('p', e['decFactor']);
                let input = genAttrElement('input', 'type', 'checkbox');
                let tr = genericElement('tr', '');
                addItem(tr, genericElement('td', img));
                addItem(tr, genericElement('td', name));
                addItem(tr, genericElement('td', price));
                addItem(tr, genericElement('td', decFactor));
                addItem(tr, genericElement('td', input));
                addItem(tbody, tr);
            }
        )
    }

    function procesData() {
        let resultData = Array.from(document.querySelectorAll("input[type='checkbox']"));
        resultData.map(e => {
            if (e.checked === true) {
                averages.push(+e.parentNode.previousElementSibling.textContent);
                totalPrice += +e.parentNode.previousElementSibling.previousElementSibling.textContent;
                goodsBuyed.push(e.parentNode.previousElementSibling.previousElementSibling.previousElementSibling.textContent);
            }
        });
        avgDecFactor = averages.reduce((a, b) => a + b, 0) / averages.length;
        result.value += "Bought furniture: " + goodsBuyed.join(', ') + "\n";
        result.value += "Total price: " + totalPrice.toFixed(2) + "\n";
        result.value += "Average decoration factor: " + avgDecFactor.toPrecision(1) + "\n";
    }
}