//------------------------------------------------------------------------------------------------------------
//  Práce s cookies
//------------------------------------------------------------------------------------------------------------

var MyCookie = {
    Write:function(name,value,days) {
        var D = new Date();
        D.setTime(D.getTime()+86400000*days)
        document.cookie = escape(name)+"="+escape(value)+
            ((days == null)?"":(";expires="+D.toGMTString())) + ";path=/"
        return (this.Read(name) == value);
    },
    Read:function(name) {
        var EN=escape(name)
        var F=' '+document.cookie+';', S=F.indexOf(' '+EN);
        return S==-1 ? null : unescape(     F.substring(EN=S+EN.length+2,F.indexOf(';',EN))    );
    }
}

//------------------------------------------------------------------------------------------------------------
//  AJAX - Odesílání přidání do ankety
//------------------------------------------------------------------------------------------------------------

var xmlhttp = null;

function AddAnswer(ID) {
    if (MyCookie.Read("QuestionnaireOK") == "True") {
        alert("Do ankety lze hlasovat pouze jednou za den!");
        return;
    } else {
        MyCookie.Write("QuestionnaireOK", "True", 1);
    }

    if (window.XMLHttpRequest) 
    {
        xmlhttp = new XMLHttpRequest(); // code for Mozilla, etc.
    } 
    else 
    {
        if (window.ActiveXObject) 
        {
            xmlhttp = new ActiveXObject("Microsoft.XMLHTTP"); // code for IE
        }
    }
    
    if (xmlhttp != null) 
    {
        xmlhttp.open("POST", "http://www.karelcerny.cz/Scripts/Questionnaire.ashx?id=" + ID, true);
        xmlhttp.onreadystatechange = onResponse;
        xmlhttp.send(null);
    }
    else alert("Your browser does not support XMLHTTP.");
}

function checkReadyState(obj) {
    if (obj.readyState == 4)
    {
        if(obj.status == 200)
        {
            return true;
        }
        else
        {
            alert("Problem retrieving XML data");
        }
    }
}

function onResponse() {
    if(!checkReadyState(xmlhttp))
        return;
    if (xmlhttp.responseText != "true") {
        alert(xmlhttp.responseText);
    } else {
        alert("Děkujeme za Váš názor.");
    }
}