// Author: Matt Kruse <matt@mattkruse.com>
// WWW: http://www.mattkruse.com/

function getAnchorPosition(anchorname) {
	var useWindow=false;
	var coordinates=new Object();
	var x=0, y=0;
	var use_gebi=false, use_css=false, use_layers=false;
	
	if (document.getElementById) {
		use_gebi=true;
	} else if (document.all) {
		use_css=true;
	} else if (document.layers) {
		use_layers=true;
	}
	
	if (use_gebi) {
		var o = document.getElementById(anchorname);
		
		x=AnchorPosition_getPageOffsetLeft(o);
		y=AnchorPosition_getPageOffsetTop(o);
		
	} else if (use_css) {
		x = AnchorPosition_getPageOffsetLeft(document.all[anchorname]);
		y = AnchorPosition_getPageOffsetTop(document.all[anchorname]);
		
	} else if (use_layers) {
		var found = 0;
		
		for (var i=0; i<document.anchors.length; i++) {
			if (document.anchors[i].name==anchorname) {
				found = 1;
				break;
			}
		}
		
		if (found == 0) {
			coordinates.x = 0;
			coordinates.y = 0;
			
			return coordinates;
		}
		
		x=document.anchors[i].x;
		y=document.anchors[i].y;
		
	} else {
		coordinates.x = 0;
		coordinates.y = 0;
		
		return coordinates;
	}
	
	coordinates.x = x;
	coordinates.y = y;
	
	return coordinates;
}

function AnchorPosition_getPageOffsetLeft (el) {
	var ol=el.offsetLeft;
	
	while ((el=el.offsetParent) != null) {
		ol += el.offsetLeft;
	}
	return ol;
}

function AnchorPosition_getWindowOffsetLeft (el) {
	return AnchorPosition_getPageOffsetLeft(el) - document.body.scrollLeft;
}

function AnchorPosition_getPageOffsetTop (el) {
	var ot=el.offsetTop;
	
	while((el=el.offsetParent) != null) {
		ot += el.offsetTop;
	}
	return ot;
}

function AnchorPosition_getWindowOffsetTop (el) {
	return AnchorPosition_getPageOffsetTop(el) - document.body.scrollTop;
}