/*
	name			: ClassBehaviours, the javascript framework based on class-name parsing
	update			: 9.11.9
	author			: Maurice van Creij
	dependencies	: jquery.classbehaviours.js
	info			: http://www.classbehaviours.com/

    This file is part of jQuery.classBehaviours.

    ClassBehaviours is a javascript framework based on class-name parsing.
    Copyright (C) 2008  Maurice van Creij

    ClassBehaviours is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    ClassBehaviours is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with ClassBehaviours. If not, see http://www.gnu.org/licenses/gpl.html.
*/

	// create the jQuery object if it doesn't already exist
	if(typeof(jQuery)=='undefined') jQuery = function(){};

	// create the root classbehaviours object if it doesn't already exist
	if(typeof(jQuery.classBehaviours)=='undefined') jQuery.classBehaviours = function(){};

	// create the handlers child object if it doesn't already exist
	if(typeof(jQuery.classBehaviours.handlers)=='undefined') jQuery.classBehaviours.handlers = function(){}

	// Manages an artificial scroll bar
	jQuery.classBehaviours.handlers.artificialScrollBar = {
		// properties
		name: 'artificialScrollBar',
		interaction: false,
		interactor: null,
		scrollInterval: null,
		index: 0,
		// methods
		start: function(node){
			// give the scrollbar an id if it doesn't have one
			node.id = (node.id) ? node.id : this.name + this.index++ ;
			// get the objects inside
			allDivs = node.getElementsByTagName('DIV');
			// disable the normal scrollbar
			node.style.overflow = 'hidden';
			// show the artificial scrollbar
			allDivs[allDivs.length-5].style.display = 'block';
			// set the canvas event handlers
			node.onmouseover = this.overCanvas;
			node.onmouseout = this.offCanvas;
			// set the detector events
			allDivs[allDivs.length-1].onmousedown = this.onDown;
			allDivs[allDivs.length-1].onmousemove = this.onDrag;
			allDivs[allDivs.length-1].ondrag = this.onDrag;
			node.onmouseup = this.onUp;
			node.onmousewheel = this.onWheel;
			if(window.addEventListener) window.addEventListener('DOMMouseScroll', this.onWheel, false);
			// set the button event handlers
			allDivs[allDivs.length-3].onmousedown = this.buttonDown;
			allDivs[allDivs.length-3].onmouseup = this.buttonOff;
			allDivs[allDivs.length-3].onmouseout = this.buttonOff;
			allDivs[allDivs.length-4].onmousedown = this.buttonUp;
			allDivs[allDivs.length-4].onmouseup = this.buttonOff;
			allDivs[allDivs.length-4].onmouseout = this.buttonOff;
			// start position
			setTimeout('jQuery.classBehaviours.handlers.artificialScrollBar.moveTo(document.getElementById("'+node.id+'"), 0)', 100);
		},
		resize: function(rootNode){
			// get the required objects
			allDivs = rootNode.getElementsByTagName('DIV');
			contentNode = allDivs[0];
			indicatorNode = allDivs[allDivs.length-2];
		},
		moveTo: function(rootNode, position){
			// get the required objects
			allDivs = rootNode.getElementsByTagName('DIV');
			contentNode = allDivs[0];
			indicatorNode = allDivs[allDivs.length-2];
			scrollBarNode = allDivs[allDivs.length-5];
			// size the indicator
			contentToWindowRatio = contentNode.parentNode.offsetHeight / contentNode.offsetHeight;
			scrollBarHeight = indicatorNode.parentNode.offsetHeight;
			indicatorSize = contentToWindowRatio * scrollBarHeight;
			if(!isNaN(indicatorSize)) indicatorNode.style.height = Math.round(indicatorSize - 3) + 'px';
			// hide the indicator when it's not needed
			scrollBarNode.style.visibility = (contentToWindowRatio>=1) ? 'hidden' : 'visible' ;
			// if the page is longer than the canvas
			if(contentToWindowRatio<1){
				// set the indicator position
				indicatorSurplus = indicatorSize / 2;
				indicatorPosition = position - indicatorSurplus;
				if(position < indicatorSurplus) indicatorPosition = 0;
				if(indicatorPosition > scrollBarHeight-indicatorSize) indicatorPosition = scrollBarHeight-indicatorSize;
				if(!isNaN(indicatorPosition)) indicatorNode.style.top = Math.round(indicatorPosition + 3) + 'px';
				// set the content position
				scrollBarFraction = (position - indicatorSurplus) / (scrollBarHeight - indicatorSurplus * 2);
				contentOverlap = contentNode.offsetHeight - contentNode.parentNode.offsetHeight;
				contentPosition = scrollBarFraction * contentOverlap;
				if(contentPosition<0) contentPosition = 0;
				if(contentPosition>contentOverlap) contentPosition = contentOverlap;
				if(!isNaN(contentPosition)) contentNode.style.top = Math.round(0 - contentPosition) + "px";
			}
		},
		moveBy: function(rootNode, distance){
			if(rootNode){
				// get the required objects
				allDivs = rootNode.getElementsByTagName('DIV');
				contentNode = allDivs[0];
				indicatorNode = allDivs[allDivs.length-2];
				// get the current scroll position
				indicatorPosition = (indicatorNode.style.top) ? parseInt(indicatorNode.style.top) : 0 ;
				indicatorSize = (indicatorNode.style.height) ? parseInt(indicatorNode.style.height) : 0 ;
				// set the new scroll position
				this.moveTo(rootNode, indicatorPosition+indicatorSize/2+distance);
			}
		},
		// events
		onDown: function(that){
			var objNode = (typeof(this.nodeName)=='undefined') ? that : this ;
			var asb = jQuery.classBehaviours.handlers.artificialScrollBar;
			// activate the controls
			asb.interaction = true;
			// get the interaction location
			mouseY = (typeof(event)!='undefined' && navigator.userAgent.indexOf('Safari')<0) ? event.y : that.layerY ;
			// send the coordinates to the indicator
			asb.moveTo(objNode.parentNode.parentNode, mouseY);
			// cancel the click
			return false;
		},
		onDrag: function(that){
			var objNode = (typeof(this.nodeName)=='undefined') ? that : this ;
			var asb = jQuery.classBehaviours.handlers.artificialScrollBar;
			// if the controls are active
			if(asb.interaction){
				// get the interaction location
				mouseY = (typeof(event)!='undefined' && navigator.userAgent.indexOf('Safari')<0) ? event.y : that.layerY ;
				// send the coordinates to the indicator
				asb.moveTo(objNode.parentNode.parentNode, mouseY);
				// cancel the click
				return false;
			}
		},
		onUp: function(that){
			var objNode = (typeof(this.nodeName)=='undefined') ? that : this ;
			var asb = jQuery.classBehaviours.handlers.artificialScrollBar;
			// de-activate the controls
			asb.interaction = false;
			// cancel the click
			return false;
		},
		buttonUp: function(that){
			var objNode = (typeof(this.nodeName)=='undefined') ? that : this ;
			var asb = jQuery.classBehaviours.handlers.artificialScrollBar;
			// move the scroller 1 step up
			asb.moveBy(asb.interactor, -5);
			// set an interval
			asb.scrollInterval = setInterval("jQuery.classBehaviours.handlers.artificialScrollBar.moveBy(jQuery.classBehaviours.handlers.artificialScrollBar.interactor, -5)", 50);
			// cancel the click
			return false;
		},
		buttonDown: function(that){
			var objNode = (typeof(this.nodeName)=='undefined') ? that : this ;
			var asb = jQuery.classBehaviours.handlers.artificialScrollBar;
			// move the scroller 1 step down
			asb.moveBy(asb.interactor, 5);
			// set an interval
			asb.scrollInterval = setInterval("jQuery.classBehaviours.handlers.artificialScrollBar.moveBy(jQuery.classBehaviours.handlers.artificialScrollBar.interactor, 5)", 50);
			// cancel the click
			return false;
		},
		buttonOff: function(that){
			var objNode = (typeof(this.nodeName)=='undefined') ? that : this ;
			var asb = jQuery.classBehaviours.handlers.artificialScrollBar;
			// clear the scrolling interval
			clearInterval(asb.scrollInterval);
			// cancel the click
			return false;
		},
		onWheel: function(that){
			var objNode = (typeof(this.nodeName)=='undefined') ? that : this ;
			var asb = jQuery.classBehaviours.handlers.artificialScrollBar;
			// get the scroll distance
			distance = (window.event) ? window.event.wheelDelta/120 : -objNode.detail/3 ;
			// scroll the page
			asb.moveBy(asb.interactor, -5*distance);
			// cancel the click
			return false;
		},
		overCanvas: function(that){
			var objNode = (typeof(this.nodeName)=='undefined') ? that : this ;
			var asb = jQuery.classBehaviours.handlers.artificialScrollBar;
			// store the object hovered over
			asb.interactor = objNode;
		},
		offCanvas: function(that){
			var objNode = (typeof(this.nodeName)=='undefined') ? that : this ;
			var asb = jQuery.classBehaviours.handlers.artificialScrollBar;
			// store the object hovered over
			asb.interactor = null;
		}
	}

	// add this addon to the jQuery object
	if(typeof(jQuery.fn)!='undefined'){
		// extend jQuery with this method
		jQuery.fn.artificialScrollBar = function(){
			return this.each(
				function(){
					jQuery.classBehaviours.handlers.artificialScrollBar.start(this);
				}
			);
		};
		// set the event handler for this jQuery method
		$(document).ready(
			function(){
				$(".artificialScrollBar").artificialScrollBar();
			}
		);
	}