function GetCookie(name) {
    var arg = name + "=";
    var alen = arg.length;
    var clen = document.cookie.length;
    var i = 0;
    while (i < clen) {
        var j = i + alen;
        if (document.cookie.substring(i, j) == arg)
            return getCookieVal(j);
        i = document.cookie.indexOf(" ", i) + 1;
        if (i == 0) break;
    }
    return null;
}


function SetCookie(name, value) {
    var argv = SetCookie.arguments;
    var argc = SetCookie.arguments.length;
    var expires = (argc > 2) ? argv[2] : null;
    var path = (argc > 3) ? argv[3] : null;
    var domain = (argc > 4) ? argv[4] : null;
    var secure = (argc > 5) ? argv[5] : false;

    document.cookie = name + "=" + escape(value) +
        ((expires == null) ? "" : ("; expires=" + expires.toGMTString())) +
        ((path == null) ? "" : ("; path=" + path)) +
        ((domain == null) ? "" : ("; domain=" + domain)) +
        ((secure == true) ? "; secure" : "");
}


function DeleteCookie(name) {
    var exp = new Date();
    exp.setTime(exp.getTime() - 1);
    var cval = GetCookie(name);
    document.cookie = name + "=" + cval + "; expires=" + exp.toGMTString();
}


function getCookieVal(offset) {
    var endstr = document.cookie.indexOf(";", offset);
    if (endstr == -1)
        endstr = document.cookie.length;
    return unescape(document.cookie.substring(offset, endstr));
}

function checkResolution() {
    var res = GetCookie('resolution');

    if (res == null) {
        w = screen.width; // -> gaat mis met 2 monitoren en 1tje op high en de andere op low 

        if (window.innerWidth) {
            w = window.innerWidth;
        } else {
            if (!(document.documentElement.clientWidth == 0)) { //strict mode
                w = document.documentElement.clientWidth;
            } else { //quirks mode
                w = document.body.clientWidth;
            }
        }

        actual_res = 1024; //default
        if (w > 1024) actual_res = 1280;
        //        if (w > 1280) actual_res = 1360;
        //        if (w > 1360) actual_res = 1440;
        //        if (w > 1440) actual_res = 1600;
        //        if (w > 1600) actual_res = 1680;
        //        if (w > 1680) actual_res = 1920;

        //alert(w);
        SetCookie('resolution', actual_res);

        if (w <= 1024 && navigator.cookieEnabled)
            location.href = location.href; // dit gaat mis zonder cookies
    }
}


if (window.addEventListener) {
    window.addEventListener("load", checkResolution, false);
} else if (window.attachEvent) {
    window.attachEvent("onload", checkResolution);
}