Creating a cookie with a array

gistfile1.js

<script>
function getCookie(c_name) {
    if (document.cookie.length > 0) {
        c_start = document.cookie.indexOf(c_name + "=");
    if (c_start != -1) {
        c_start = c_start + c_name.length + 1;
    c_end = document.cookie.indexOf(";", c_start);
            if (c_end == -1) {
        c_end = document.cookie.length;
    }
    return unescape(document.cookie.substring(c_start, c_end));
}
}
return "";
}

function cookieInit() {

        document.cookie = "dup=1; expires=Thu, 18 Dec 2040 12:00:00 UTC; path=/";
    pagesCookie = getCookie("pages");
    if (pagesCookie == '') {
        var pages =  [window.location.href];
document.cookie = "pages="+JSON.stringify(pages)+ "; expires=Thu, 18 Dec 2040 12:00:00 UTC; path=/";
}
else
    {
    var json_str, pagesArr;
    json_str = getCookie("pages");
    pagesArr  = JSON.parse(json_str);
    currentUrl = window.location.href;

    if(!pagesArr.includes(currentUrl)){
        pagesArr.push(currentUrl);
        document.cookie = "pages="+JSON.stringify(pagesArr)+ "; expires=Thu, 18 Dec 2040 12:00:00 UTC; path=/";
    }
 }
}
cookieInit();

</script>