// Browser detection
var doms = document.getElementById ? true:false;
var nn4 = document.layers ? true:false;
var ie4 = document.all ? true:false;

var mouseY; 
var mouseX; 

var clickUp = false; 
var clickDown = false; 
var clickDrag = false; 
var clickAbove = false;
var clickBelow = false;

var timer = setTimeout("",500);
var upL; 
var upT; 
var downL; 
var downT; 
var dragL; 
var dragT; 
var rulerL;
var rulerT;
var contentT;
var contentH;
var contentClipH;
var scrollLength;
var startY;


function down(e){
	if((document.layers && e.which!=1) || (document.all && event.button!=1)) return true; 
	getMouse(e);
	startY = (mouseY - dragT);
	

	if(mouseX >= upL && (mouseX <= (upL + upW)) && mouseY >= upT && (mouseY <= (upT + upH))){
		clickUp = true;
		return scrollUp();
	}	

	else if(mouseX >= downL && (mouseX <= (downL + downW)) && mouseY >= downT && (mouseY <= (downT + downH))){
		clickDown = true;
		return scrollDown();
	}

	else if(mouseX >= dragL && (mouseX <= (dragL + dragW)) && mouseY >= dragT && (mouseY <= (dragT + dragH))){
		clickDrag = true;
		return false;
	}
	else if(mouseX >= dragL && (mouseX <= (dragL + dragW)) && mouseY >= rulerT && (mouseY <= (rulerT + scrollH))){

		if(mouseY < dragT){
			clickAbove = true;
			clickUp = true;
			return scrollUp();
		}

		else{
			clickBelow = true;
			clickDown = true;
			return scrollDown();
		}
	}

	else{
		return true;
	}
}


function move(e){
	if(clickDrag && contentH > contentClipH){
		getMouse(e);
		dragT = (mouseY - startY);
		
		if(dragT < (rulerT))
			dragT = rulerT;		
		if(dragT > (rulerT + scrollH - dragH))
			dragT = (rulerT + scrollH - dragH);
		
		contentT = ((dragT - rulerT)*(1/scrollLength));
		contentT = eval('-' + contentT);

		moveTo();
		

		if(ie4)
			return false;
	}
}

function up(){
    clearTimeout(timer);

	clickUp = false;
	clickDown = false;
	clickDrag = false;
	clickAbove = false;
	clickBelow = false;
	return true;
}

function getT(){
	if(ie4)
		contentT = document.all.content.style.pixelTop;
	else if(nn4)
		contentT = document.contentClip.document.content.top;
	else if(doms)
		contentT = parseInt(document.getElementById("content").style.top);
}


function getMouse(e){
	if(ie4){
		mouseY = event.clientY + document.body.scrollTop;
		mouseX = event.clientX + document.body.scrollLeft;
	}
	else if(nn4 || doms){
		mouseY = e.pageY;
		mouseX = e.pageX;
	}
}


function moveTo(){
	if(ie4){
		document.all.content.style.top = contentT;
		curContentTop = parseInt(contentT);
		document.all.ruler.style.top = dragT;
		document.all.drag.style.top = dragT;
		curDragTop = parseInt(dragT);
	}
	else if(nn4){
		document.contentClip.document.content.top = contentT;
		curContentTop = parseInt(contentT);
		document.ruler.top = dragT;
		document.drag.top = dragT;
		curDragTop = parseInt(dragT);
	}
	else if(doms){
		document.getElementById("content").style.top = contentT + "px";
		curContentTop = contentT;
		document.getElementById("drag").style.top = dragT + "px";
		curDragTop = dragT;
		document.getElementById("ruler").style.top = dragT + "px";
	}
}


function scrollUp(){
	getT();
	
	if(clickAbove){
		if(dragT <= (mouseY-(dragH/2)))
			return up();
	}
	
	if(clickUp){
		if(contentT < 0){		
			dragT = dragT - (speed*scrollLength);
			
			if(dragT < (rulerT))
				dragT = rulerT;
				
			contentT = contentT + speed;
			if(contentT > 0)
				contentT = 0;
			
			moveTo();
			timer = setTimeout("scrollUp()",25);
		}
	}
	return false;
}


function scrollDown(){
	getT();
	
	if(clickBelow){
		if(dragT >= (mouseY-(dragH/2)))
			return up();
	}

	if(clickDown){
		if(contentT > -(contentH - contentClipH)){			
			dragT = dragT + (speed*scrollLength);
			if(dragT > (rulerT + scrollH - dragH))
				dragT = (rulerT + scrollH - dragH);
			
			contentT = contentT - speed;
			if(contentT < -(contentH - contentClipH))
				contentT = -(contentH - contentClipH);
			
			moveTo();
			timer = setTimeout("scrollDown()",25);
		}
	}
	return false;
}


function reloadPage(){
	location.reload();
}


function eventLoader(){
var scrollers = new Array('up','down','ruler','drag','background');


	if(ie4){
		upL = document.all.up.style.pixelLeft;
		upT = document.all.up.style.pixelTop;

		downL = document.all.down.style.pixelLeft;
		downT = document.all.down.style.pixelTop;

		dragL = document.all.drag.style.pixelLeft;
		dragT = document.all.drag.style.pixelTop;

		rulerT = document.all.ruler.style.pixelTop;

		contentH = parseInt(document.all.content.scrollHeight);
		contentClipH = parseInt(document.all.contentClip.style.height);
		document.all.contentClip.style.visibility="visible";
	}
	else if(nn4){
		upL = document.up.left;
		upT = document.up.top;		

		downL = document.down.left;
		downT = document.down.top;		

		dragL = document.drag.left;
		dragT = document.drag.top;		

		rulerT = document.ruler.top;

		contentH = document.contentClip.document.content.clip.bottom;
		contentClipH = document.contentClip.clip.bottom;
		document.contentClip.style.visibility="visible";
	}
	else if(doms){
		upL = parseInt(document.getElementById("up").style.left);
		upT = parseInt(document.getElementById("up").style.top);

		downL = parseInt(document.getElementById("down").style.left);
		downT = parseInt(document.getElementById("down").style.top);

		dragL = parseInt(document.getElementById("drag").style.left);
		dragT = parseInt(document.getElementById("drag").style.top);

		rulerT = parseInt(document.getElementById("ruler").style.top);
		
		contentH = parseInt(document.getElementById("content").offsetHeight);
		contentClipH = parseInt(document.getElementById("contentClip").offsetHeight);
		document.getElementById("content").style.top = 0 + "px";
		document.getElementById("contentClip").style.visibility= "visible";
		
	}
	
	if ( contentH > contentClipH)
		{		
			for (var i=0; i<scrollers.length;i++) 
	   		{
        	scrollers[i] = new makeStyleObject(scrollers[i])
        	}
			
			for (var i=0;i<scrollers.length;i++) 
            {
			scrollers[i].el.visibility="visible"
	    }
	}

	if (contentH < contentClipH) {
		dom.handles['drag'].style.visibility = "hidden";
	}
	
	scrollLength = ((scrollH-dragH)/(contentH-contentClipH));

	if(nn4){
		document.captureEvents(Event.MOUSEDOWN | Event.MOUSEMOVE | Event.MOUSEUP);
		window.onresize = reloadPage;
	}
	document.onmousedown = down;
	document.onmousemove = move;
	document.onmouseup = up;
}


function makeStyleObject(id)
{
    if (document.getElementById)
        {
        this.el = document.getElementById(id).style
        }
    else if (document.layers)
        {
        this.el = document.layers[id]
        }
    else if (document.all) 
        {
        this.el = document.all[id].style
        }
    return this
}

// Added this function for use of scrollwheel and anchor jumping
function jumpto() {
	if (typeof curContentTop == 'undefined') {
		if (dom.handles['content'].style.top == '') {
			curContentTop = 0;
		} else {
			curContentTop = parseInt(dom.handles['content'].style.top);
		}
	}
	if (typeof curDragTop == 'undefined') {
		curDragTop = parseInt(dom.handles['drag'].style.top);
	}
	scrollEvent = event.wheelDelta;
	scrollDirection = scrollEvent/120;
	
	mousewheelMod = (contentClipH/contentH)*100;
	if (mousewheelMod < 1) { mousewheelMod = 1; }
	if (mousewheelMod > 100) { mousewheelMod = 100; }
	contentPixelsToScroll = (contentH-contentClipH)/500*mousewheelMod;
	DragPixelsToScroll = (scrollH-dragH)/500*mousewheelMod;
	
	dom.handles['content'].style.top = curContentTop + (scrollDirection*contentPixelsToScroll);
	contentT = curContentTop + (scrollDirection*contentPixelsToScroll);
	curContentTop = curContentTop + (scrollDirection*contentPixelsToScroll);
	dom.handles['drag'].style.top = curDragTop + (-scrollDirection*DragPixelsToScroll);
	dragT = curDragTop + (-scrollDirection*DragPixelsToScroll);
	curDragTop = curDragTop + (-scrollDirection*DragPixelsToScroll);
	
	if (curContentTop >= 0) {
		dom.handles['content'].style.top = 0;
		contentT = 0;
		curContentTop = 0;
		dom.handles['drag'].style.top = AnchorDragTop;
		dragT = AnchorDragTop;
		curDragTop = AnchorDragTop;
		return false;
	}
	
	if (contentClipH-contentH >= curContentTop) {
		dom.handles['content'].style.top = contentClipH-contentH;
		contentT = contentClipH-contentH;
		curContentTop = contentClipH-contentH;
		dom.handles['drag'].style.top = AnchorDragTop+scrollH-dragH;
		dragT = AnchorDragTop+scrollH-dragH;
		curDragTop = AnchorDragTop+scrollH-dragH;
		return false;
	}
}

function scrollbar_mousewheel() {
	if (contentH > contentClipH) {
		jumpto();
	}
}

// Added this function for use of anchors
function ankerjump(imgid) {
	if (typeof curContentTop == 'undefined') {
		if (dom.handles['content'].style.top == '') {
			curContentTop = 0;
		} else {
			curContentTop = parseInt(dom.handles['content'].style.top);
		}
	}
	if (typeof curDragTop == 'undefined') {
		curDragTop = parseInt(dom.handles['drag'].style.top);
	}
	
	offset = _get_offset(document.images[imgid]);
	offsety = offset['y'];
	offsety = offsety - curContentTop;
	contentPixelsToScroll = offsety - AnchorContentTop;
	dom.handles['content'].style.top = -contentPixelsToScroll;
	contentT = -contentPixelsToScroll;
	curContentTop = -contentPixelsToScroll;
	
	// Calculate Relation of Proportion
	calcROP = (1/((contentH-contentClipH)/contentPixelsToScroll));
	DragPixelsToScroll = ((scrollH-dragH)*calcROP)+ AnchorDragTop;
	DragPixelsToScroll = Math.round(DragPixelsToScroll);
	dom.handles['drag'].style.top = DragPixelsToScroll;
	dragT = DragPixelsToScroll;
	curDragTop = DragPixelsToScroll;
	
	if (curContentTop >= 0) {
		dom.handles['content'].style.top = 0;
		contentT = 0;
		curContentTop = 0;
		dom.handles['drag'].style.top = AnchorDragTop;
		dragT = AnchorDragTop;
		curDragTop = AnchorDragTop;
		return false;
	}
	
	if (contentClipH-contentH >= curContentTop) {
		dom.handles['content'].style.top = contentClipH-contentH;
		contentT = contentClipH-contentH;
		curContentTop = contentClipH-contentH;
		dom.handles['drag'].style.top = AnchorDragTop+scrollH-dragH;
		dragT = AnchorDragTop+scrollH-dragH;
		curDragTop = AnchorDragTop+scrollH-dragH;
		return false;
	}
}

function anker(imgid) {
	if (contentH > contentClipH) {
		ankerjump([imgid]);
	}
}