// JavaScript Document
function Position(x, y)
{
  this.X = x;
  this.Y = y;
  
  this.Add = function(val)
  {
    var newPos = new Position(this.X, this.Y);
    if(val != null)
    {
      if(!isNaN(val.X))
        newPos.X += val.X;
      if(!isNaN(val.Y))
        newPos.Y += val.Y
    }
    return newPos;
  }
  
  this.Subtract = function(val)
  {
    var newPos = new Position(this.X, this.Y);
    if(val != null)
    {
      if(!isNaN(val.X))
        newPos.X -= val.X;
      if(!isNaN(val.Y))
        newPos.Y -= val.Y
    }
    return newPos;
  }
  
  this.Min = function(val)
  {
    var newPos = new Position(this.X, this.Y)
    if(val == null)
      return newPos;
    
    if(!isNaN(val.X) && this.X > val.X)
      newPos.X = val.X;
    if(!isNaN(val.Y) && this.Y > val.Y)
      newPos.Y = val.Y;
    
    return newPos;  
  }
  
  this.Max = function(val)
  {
    var newPos = new Position(this.X, this.Y)
    if(val == null)
      return newPos;
    
    if(!isNaN(val.X) && this.X < val.X)
      newPos.X = val.X;
    if(!isNaN(val.Y) && this.Y < val.Y)
      newPos.Y = val.Y;
    
    return newPos;  
  }  
  
  this.Bound = function(lower, upper)
  {
    var newPos = this.Max(lower);
    return newPos.Min(upper);
  }
  
  this.Check = function()
  {
    var newPos = new Position(this.X, this.Y);
    if(isNaN(newPos.X))
      newPos.X = 0;
    if(isNaN(newPos.Y))
      newPos.Y = 0;
    return newPos;
  }
  
  this.Apply = function(element)
  {
    if(typeof(element) == "string")
      element = document.getElementById(element);
    if(element == null)
      return;
    if(!isNaN(this.X))
      element.style.left = this.X + 'px';
    if(!isNaN(this.Y))
      element.style.top = this.Y + 'px';  
  }
}

function absoluteCursorPostion(eventObj)
{
  eventObj = eventObj ? eventObj : window.event;
  
  if(isNaN(window.scrollX))
    return new Position(eventObj.clientX + document.documentElement.scrollLeft + document.body.scrollLeft, 
      eventObj.clientY + document.documentElement.scrollTop + document.body.scrollTop);
  else
    return new Position(eventObj.clientX + window.scrollX, eventObj.clientY + window.scrollY);
}

//If you set the number of days to 0 the cookie is trashed when the user closes the browser. 
//If you set the days to a negative number the cookie is trashed immediately.
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 = "";
	document.cookie = name+"="+value+expires+"; path=/";
}

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,"",-1);
}
