var cart = {};

$(document).ready(function () {
    checkCart();
    showMiniCart();

    $('button.btn-primary').on('click', function () {
        var articul = $(this).attr('data-art');
        if (cart[articul] != undefined) {
            cart[articul]++;
        } else {
            cart[articul] = 1;
        }
        localStorage.setItem('cart', JSON.stringify(cart));
        showMiniCart();
    });

});

function checkCart() {
    if (localStorage.getItem('cart') != null) {
        cart = JSON.parse(localStorage.getItem('cart'));
    }
}

function showMiniCart() {
    var out = '';
    for (var i in cart) {
        out += i + '---' + cart[i] + '<br>';
    }
    out += '<br><a href="/cart">Корзина</a>';
    $('#mini-cart').html(out);
}