function createCookie(name,value,days) 
{
  if(days) 
  {
    var date = new Date();
    date.setTime(date.getTime()+(days*24*60*60*1000));
    var expires = "; expires="+date.toGMTString();
  }
  else 
  {
    var expires = "";
  }
  
  var domain = "."+window.location.hostname;
  
  document.cookie = name+"="+value+expires+"; path=/; domain="+domain+";"
}

function readCookie(name) 
{
  var nameEQ = name + "=";
  var ca = document.cookie.split(';');

  for(var i=0;i < ca.length;i++) 
  {
    var c = ca[i];
    while (c.charAt(0)==' ') 
    {
      c = c.substring(1,c.length);
    }
		
    if (c.indexOf(nameEQ) == 0) 
    {
      return c.substring(nameEQ.length,c.length);
    }
  }

  return null;
}

function eraseCookie(name) 
{
  createCookie(name,"","Thu, 01-Jan-1970 00:00:01 GMT");
}

function signOutMyJS()
{
  eraseCookie("user_language");
  eraseCookie("user_wordfile");
  eraseCookie("user_email");
  eraseCookie("user_id");
  
  setVistorIDCookie();
}

function setVistorIDCookie() 
{
  if(document.cookie.indexOf("user_id=") == -1 || readCookie("user_id") == "")
  {  
    var chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXTZabcdefghiklmnopqrstuvwxyz";
    var string_length = 32;
    var randomstring = '';

    for (var i=0; i<string_length; i++) 
    {
      var rnum = Math.floor(Math.random() * chars.length);
      randomstring += chars.substring(rnum,rnum+1);
    }
      
    createCookie("user_id",randomstring,90); 
  }
}

function writeDebugLine(message)
{
  var debugdiv = document.getElementById("debugmessages");
  debugdiv.innerHTML = debugdiv.innerHTML + " | " + message;
}


function validEmail(str) 
{
  var at="@"
  var dot="."
  var lat=str.indexOf(at)
  var lstr=str.length
  var ldot=str.indexOf(dot)
  
  if (str.indexOf(at)==-1)
  {
    return false
  }

  if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr)
  {
    return false
  }

  if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr)
  {
    return false
  }

  if (str.indexOf(at,(lat+1))!=-1)
  {
    return false
  }

  if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot)
  {
    return false
  }

  if (str.indexOf(dot,(lat+2))==-1)
  {
    return false
  }

  if (str.indexOf(" ")!=-1)
  {
    return false
  }

  return true					
}