function DisableInput(id) 
{
    var element = document.getElementById(id);

    if (element.disabled == true)
        element.disabled = false;
    else
        element.disabled = true;
}

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 setCookie(c_name, value, expiredays) {
    var exdate = new Date();
    exdate.setDate(exdate.getDate() + expiredays);
    document.cookie = c_name + "=" + escape(value) +
((expiredays == null) ? "" : ";expires=" + exdate.toGMTString());
}

function checkCookie() {
    username = getCookie('username');
    if (username != null && username != "") {
        alert('Welcome again ' + username + '!');
    }
    else {
        username = prompt('Please enter your name:', "");
        if (username != null && username != "") {
            setCookie('username', username, 365);
        }
    }
}

function ShowDivWindow(url) {
    ShowHide('black_screen', 'show');
    ShowHide('div_window', 'show');
    document.getElementById('div_window_content').src = url;
}

function HideDivWindow() {
    ShowHide('black_screen');
    ShowHide('div_window');
}


function ShowHide(id, type) {
    var element = document.getElementById(id);

    if (((element.style.display == '' || element.style.display == 'none') && type == 'switch') || type == 'show')
        element.style.display = 'block';
    else
        element.style.display = 'none';
}