Ozein.Screen = {
  getScrollOffset: function() {
	var xScroll, yScroll;

	if (self.pageYOffset) {
		yScroll = self.pageYOffset;
		xScroll = self.pageXOffset;
	} else if (document.documentElement && document.documentElement.scrollTop){	 // Explorer 6 Strict
		yScroll = document.documentElement.scrollTop;
		xScroll = document.documentElement.scrollLeft;
	} else if (document.body) {// all other Explorers
		yScroll = document.body.scrollTop;
		xScroll = document.body.scrollLeft;	
	}

	arrayPageScroll = new Array(xScroll,yScroll) 
	return arrayPageScroll;
  },
  getSize: function() {
	var xScroll, yScroll;
	
	if (window.innerHeight && window.scrollMaxY) {	
		xScroll = window.innerWidth + window.scrollMaxX;
		yScroll = window.innerHeight + window.scrollMaxY;
	} else if (document.body.scrollHeight > document.body.offsetHeight){ // all but Explorer Mac
		xScroll = document.body.scrollWidth;
		yScroll = document.body.scrollHeight;
	} else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
		xScroll = document.body.offsetWidth;
		yScroll = document.body.offsetHeight;
	}
	
	var windowWidth, windowHeight;
	
	if (self.innerHeight) {	// all except Explorer
		if(document.documentElement.clientWidth){
			windowWidth = document.documentElement.clientWidth; 
		} else {
			windowWidth = self.innerWidth;
		}
		windowHeight = self.innerHeight;
	} else if (document.documentElement && document.documentElement.clientHeight) { // Explorer 6 Strict Mode
		windowWidth = document.documentElement.clientWidth;
		windowHeight = document.documentElement.clientHeight;
	} else if (document.body) { // other Explorers
		windowWidth = document.body.clientWidth;
		windowHeight = document.body.clientHeight;
	}	
	
	// for small pages with total height less then height of the viewport
	if(yScroll < windowHeight){
		pageHeight = windowHeight;
	} else { 
		pageHeight = yScroll;
	}

	// for small pages with total width less then width of the viewport
	if(xScroll < windowWidth){
		pageWidth = xScroll;
	} else {
		pageWidth = windowWidth;
	}

	arrayPageSize = new Array(pageWidth,pageHeight,windowWidth,windowHeight) 
	return arrayPageSize;
  },
  setCenterPosition: function(node) {
    var size = Ozein.Screen.getSize();
    var offset = Ozein.Screen.getScrollOffset();
    var w = size[2];
    var h = size[3];
    var left = ((w - Element.getWidth(node))/2);
    var top  = ((h - Element.getHeight(node))/2);
    node.style.position = 'absolute';
    node.style.left = left + offset[0] + 'px';
    node.style.top  = top  + offset[1] + 'px';
  },
  setNearPosition: function(node, nearNode, y) {
    var nearNodeOffset = Position.positionedOffset(nearNode);
    var nearNodeOffset_x = nearNodeOffset[0];
    var nearNodeOffset_y = nearNodeOffset[1];
    var delta_x =  -50;
    var delta_y =  -90;
    var topTyousei = 0;
    if (y) {
        topTyousei = y;
    }
    
    node.style.position = 'absolute';
    node.style.zIndex = 1001;
    node.style.left = nearNodeOffset_x + delta_x + 'px';
    node.style.top  = nearNodeOffset_y + delta_y + topTyousei + 'px';
    
    return nearNodeOffset_y + delta_y + topTyousei;
  },
  setOffSetPosition: function(node, nearNode, y, x) {
    var nearNodeOffset = Position.positionedOffset(nearNode);
    var nearNodeOffset_x = nearNodeOffset[0];
    var nearNodeOffset_y = nearNodeOffset[1];
    var topTyousei = 0;
    var leftTyousei = 0;
    if (y) {
        topTyousei = y;
    }
    if (x) {
        leftTyousei = x;
    }
    
    node.style.position = 'absolute';
    node.style.zIndex = 1001;
    node.style.left = nearNodeOffset_x + leftTyousei + 'px';
    node.style.top  = nearNodeOffset_y + topTyousei + 'px';
  }
}