function check_mail(str)
{
            var myRegExp = /^([a-zA-Z0-9_\-])+([a-zA-Z0-9_\.\-])*\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})$/
            if( ! str.match( myRegExp ) )
            {
                    return false
            }
            return true
    }

function check_str(str)
{
       var myRegExp = /^[^;~\^&\*!<>"\/|%\?@$\+=\{\}\(\)\[\]\\]*$/
        if( ! str.match( myRegExp ) )
                return false

        return true
}

function check_name(str)
{
        var myRegExp = /^[^;~\^&\*!<>"\/|%\?@$0-9\+=\{\}\(\)\[\]\\]*$/ 
        if( ! str.match( myRegExp ) )
                return false

        return true
}

function check_num(str)
{
        var myRegExp = /^[0-9]{1,3}$/
        if( ! str.match( myRegExp ) )
                return false

        return true
}


function trimString(str)
{
   return str.replace(/^\s*|\s*$/g,"");
}




function setFocus()
{
    var tmpObj =document.getElementById("email");
    tmpObj.focus();
}

function submitGuessForm()
{

    if (validateGuessForm())    
    {      
        //todo - submit form
         document.regForm.submit();

         openRightPopup();
     }   

}


function openRightPopup()
{
     var w = 300;
     var h = 300;
     var p=document.getElementById("popupmsg"); 
     p.style.top = (window.screen.height-h)/2;
     p.style.left = (window.screen.width-w)/2;
     p.style.visibility = "visible";
 
}

function validateGuessForm()
{
    tmpObj =document.getElementById("email");
    tmpStr = trimString(tmpObj.value);
    if (tmpStr == "")
    {
        alert('Please enter your email address.');
        return false;
    }
    if (!check_mail(tmpStr))    
    {
        alert('Please enter a valid email address.');
        return false;
    }
      //user name validation 
    tmpObj =document.getElementById("username");
    tmpStr = trimString(tmpObj.value);
     if (tmpStr == "")
    {
        alert("Please enter your username.");
        return false;
    }
     if (!check_name(tmpStr))    
    {
        alert("Please enter a valid username.");
        return false;
    } 
      //Guess validation 
    tmpObj = document.getElementById("guess");
    tmpStr = trimString(tmpObj.value);
     if (tmpStr == "")
    {
        alert("Please enter your guess.");
        return false;
    }
    
    return true;
}