var isCSS, isW3C, isIE4, isNN4, isIE6CSS;

function initDHTMLAPI(){
	if(document.images){
		isCSS = (document.body && document.body.style)?true:false;
		isW3C = (isCSS && document.getElementById)?true:false;
		isIE4 = (isCSS && document.all)?true:false;
		isNN4 = (document.layers)?true:false;
		isIE6CSS = (document.compatMode && document.compatMode.indexOf("CSS1")>=0)?true:false;
	}
}

window.onload = initDHTMLAPI;

function seekLayer(doc, name){
	var theObj;
	for(var i=0; i<doc.layers.length; i++){
		if(doc.layers[i].name == name){
			theObj = doc.layers[i];
			break;
		}
		if(doc.layers[i].document.layeers.length>0)		
			theObj = seekLayer(document.layers[i].document, name);
	}
	return theObj;
}

function getRawObject(obj){
	var theObj;
	if(typeof obj=="string"){
		if(isW3C) theObj = document.getElementById(obj);
		else if(isIE4) theObj = document.all(obj);
		else if(isNN4) seekLayer(document.obj);
	}
	else theObj = obj;
	return theObj;
}

function getObject(obj){
	var theObj = getRawObject(obj);
	if(theObj && isCSS) theObj = theObj.style;
	return theObj;
}

function shiftTo(obj, x, y){
	var theObj = getObject(obj);
	if(theObj){
		if(isCSS){
			var units = (typeof theObj.left == "string") ? "px" : 0;
			theObj.left=x + units;
			theObj.top=y + units;
		}
		else if(isNN4) theObj.movetTo(x,y);
	}
}

function shiftBy(obj, deltaX, deltaY){
	var theObj = getObject(obj);
	if(theObj){
		if(isCSS){
			var units = (typeof theObj.left == "string") ? "px" : 0;
			theObj.left=getObjectLeft(obj)+deltaX+units;
			theObj.top=getObjectTop(obj)+deltaY+units;
		}
		else if(isNN4) theObj.movetBy(x,y);
	}
}

function setZIndex(obj, zOrder){
	var theObj = getObject(obj);
	if(theObj) theObj.zIndex=zOrder;
}

function setBGColor(obj, color){
	var theObj = getObject(obj);
	if(theObj){
		if(isNN4) theObj.bgColor = color;
		else if(isCSS) theObj.backgroundColor = color;
	}
}

function show(obj){
	var theObj = getObject(obj);
	if(theObj) theObj.visibility = "visible";
}

function hide(obj){
	var theObj = getObject(obj);
	if(theObj) theObj.visibility = "hidden";
}

function getObjectLeft(obj){
	var elem = getRawObject(obj);
	var result = 0;
	if(document.defaultView){
		var style = document.defaultView;
		var cssDecl = style.getComputedStyle(elem, "");
		result = cssDecl.getPropertyValue("left");		
	}
	else if(elem.currentStyle) result = elem.currentStyle.left;
	else if(elem.style)	result = elem.style.left;		
	else if(isNN4) result = elem.left;
	return parseInt(result);
}

function getObjectTop(obj){
	var elem = getRawObject(obj);
	var result = 0;
	if(document.defaultView){
		var style = document.defaultView;
		var cssDecl = style.getComputedStyle(elem, "");
		result = cssDecl.getPropertyValue("top");		
	}
	else if(elem.currentStyle) result = elem.currentStyle.top;
	else if(elem.style)	result = elem.style.top;		
	else if(isNN4) result = elem.top;
	return parseInt(result);
}

function getObjectWidth(obj){
	var elem = getRawObject(obj);
	var result = 0;
	if(elem.offsetWidth) result = elem.offsetWidth;	
	else if(elem.clip && elem.clip.width) result = elem.clip.width;
	else if(elem.style && elem.style.pixelWidth) result = elem.style.pixelWidth;
	return parseInt(result);
}

function getObjectHeight(obj){
	var elem = getRawObject(obj);
	var result = 0;
	if(elem.offsetHeight) result = elem.offsetHeight;	
	else if(elem.clip && elem.clip.height) result = elem.clip.height;
	else if(elem.style && elem.style.pixelHeight) result = elem.style.pixelHeight;
	return parseInt(result);
}

function getInsideWindowWidth(){
	if(window.innerWidth) return window.innerWidth;
	else if(isIE6CSS) return document.body.parentElement.clientWidth;
	else if(document.body && document.body.clientWidth) return document.body.clientWidth;
	return 0;
}

function getInsideWindowHeight(){
	if(window.innerHeight) return window.innerHeight;
	else if(isIE6CSS) return document.body.parentElement.clientHeight;
	else if(document.body && document.body.clientHeight) return document.body.clientHeight;
	return 0;
}