/**
	SlideItMoo v1.1 - Image slider
	(c) 2007-2010 Constantin Boiangiu <http://www.php-help.ro>
	MIT-style license.
	
	Changes from version 1.0
	- added continuous navigation
	- changed the navigation from Fx.Scroll to Fx.Morph
	- added new parameters: itemsSelector: pass the CSS class for divs
	- itemWidth: for elements with margin/padding pass their width including margin/padding
	
	Updates ( August 4th 2009 )
	- added new parameter 'elemsSlide'. When this is set to a value lower that the actual number of elements in HTML, it will slide at once that number of elements when navigation clicked. Default: null
	- added onChange event that returns the index of the current element
	
	Updates ( January 12th 2010 )
	- vertical sliding available. First, set your HTML to display vertically and set itemHeight:height of individual items ( including padding, border and so on ) and slideVertical:true
	- navigators ( forward/back ) no longer added by script. Instead, add them into overallContainer making their display from CSS and after add the CSS selector class to navs parameter
		IE: navs:{ 
				fwd:'.SlideItMoo_forward', 
				bk:'.SlideItMoo_back' 
			}
	- new method available resetAll(). When called, this will reset the previous settings and restart the script. Useful if you change slider content on-the-fly
	- new method available to stop autoSlide ( stopAutoSlide() ). To start autoslide back, use startAutoSlide()
**/
var SlideItMoo = new Class({
	
	Implements: [Events,Options],
	options: {
		overallContainer: null,/* outer container, contains fwd/back buttons and container for thumbnails */
		elementScrolled: null, /* has a set width/height with overflow hidden to allow sliding of elements */
		thumbsContainer: null,	/* actual thumbnails container */	
		itemsSelector: null, /* css class for inner elements ( ie: .SlideItMoo_element ) */
		itemsVisible:5, /* number of elements visible at once */
		elemsSlide: null, /* number of elements that slide at once */
		itemWidth: null, /* single element width */
		itemHeight: null, /* single element height */
		navs:{ /* starting this version, you'll need to put your back/forward navigators in your HTML */
			fwd:'.SlideItMoo_forward', /* forward button CSS selector */
			bk:'.SlideItMoo_back' /* back button CSS selector */
		},
		slideVertical: false, /* vertical sliding enabled */
		showControls:1, /* show forward/back controls */
		transition: Fx.Transitions.linear, /* transition */
		duration: 800, /* transition duration */
		direction: 1, /* sliding direction ( 1: enter from left/top; -1:enter from right/bottom ) */
		autoSlide: false, /* auto slide - as milliseconds ( ie: 10000 = 10 seconds ) */
		mouseWheelNav: false, /* enable mouse wheel nav */
		startIndex: null
		/*onChange: $empty*/
	},
	
	initialize: function(options){
		this.setOptions(options);
		/* all elements are identified on CSS selector (itemsSelector) */
		this.elements = $(this.options.thumbsContainer).getElements(this.options.itemsSelector);
		this.totalElements = this.elements.length;
		if( this.totalElements <= this.options.itemsVisible ) return;
		// width of thumbsContainer children
		var defaultSize = this.elements[0].getSize();
		this.elementWidth = this.options.itemWidth || defaultSize.x;
		this.elementHeight = this.options.itemHeight || defaultSize.y;
		this.currentElement = 0;
		this.direction = this.options.direction;
		this.autoSlideTotal = this.options.autoSlide + this.options.duration;
		if( this.options.elemsSlide == 1 ) this.options.elemsSlide = null;
		this.begin();		
	},
		
	begin: function(){	
		/* if navigation is needed and enabled, add it */
		this.addControls();
				
		// resizes the container div's according to the number of itemsVisible thumbnails
		this.setContainersSize();
		
		this.myFx = new Fx.Tween(this.options.thumbsContainer, { 
			property: (this.options.slideVertical ? 'margin-top':'margin-left'),
			wait: true, 
			transition: this.options.transition,
			duration: this.options.duration
		});		
				
		/* if autoSlide is not set, scoll on mouse wheel */
		if( this.options.mouseWheelNav && !this.options.autoSlide ){
			$(this.options.thumbsContainer).addEvent('mousewheel', function(ev){
				new Event(ev).stop();
				this.slide(-ev.wheel);								
			}.bind(this));
		}
		
		/* start index element */
		if( this.options.startIndex && this.options.startIndex > 0 && this.options.startIndex < this.elements.length ){
			for( var t = 1; t < this.options.startIndex; t++ )
				this.rearange();
		}
		
		if( this.options.autoSlide && this.elements.length > this.options.itemsVisible )
			this.startAutoSlide();		
	},
	/* resets the whole slider in case content changes */
	resetAll: function(){
		$(this.options.overallContainer).removeProperty('style');
		$(this.options.elementScrolled).removeProperty('style');
		$(this.options.thumbsContainer).removeProperty('style');
		this.stopAutoSlide();
		if( $defined( this.fwd ) ){
			this.fwd.dispose();
			this.bkwd.dispose();
		}
		this.initialize();
	},
	/* sets the containers width to leave visible only the specified number of elements */
	setContainersSize: function(){
		var overallSize = {};
		var scrollSize = {};
		var thumbsSize = {};
		
		if( this.options.slideVertical ){
			//overallSize.height = this.options.itemsVisible * this.elementHeight + 50 * this.options.showControls;
			scrollSize.height = this.options.itemsVisible * this.elementHeight;
			thumbsSize.height = this.totalElements * (this.elementHeight + 10);			
		}else{
			/* if navigation is enabled, add the width to the overall size */
			var navsSize = 0;
			if( this.options.showControls ){
				var s1 = this.fwd.getSize();
				var s2 = this.bkwd.getSize();
				var navsSize = s1.x+s2.x;
			}
			overallSize.width = this.options.itemsVisible * this.elementWidth;// + navsSize;
			scrollSize.width = this.options.itemsVisible * this.elementWidth;
			thumbsSize.width = this.totalElements * (this.elementWidth + 10);			
		}
		$(this.options.overallContainer).set({
			styles : overallSize
		});
		$(this.options.elementScrolled).set({
			styles : scrollSize
		});
		$(this.options.thumbsContainer).set({
			styles : thumbsSize
		});
	},
	/* adds forward/back buttons */
	addControls: function(){
		if( !this.options.showControls || this.elements.length <= this.options.itemsVisible ) return;
		
		this.fwd = $(this.options.overallContainer).getElement(this.options.navs.fwd);
		this.bkwd = $(this.options.overallContainer).getElement(this.options.navs.bk);
		
		if( this.fwd )
			this.fwd.addEvent('click', this.slide.pass(1, this));
			this.fwd.setStyle('display','block');
		if( this.bkwd )
			this.bkwd.addEvent('click', this.slide.pass(-1, this));
			this.bkwd.setStyle('display','block');
	},
	/* slides elements */
	slide: function( direction ){
		
		if(this.started) return;
		this.direction = direction ? direction : this.direction;
		var currentIndex = this.currentIndex();
		/* if multiple elements are to be skipped (elemsSlide > 1), calculate the ending element */
		if( this.options.elemsSlide && this.options.elemsSlide>1 && this.endingElem==null ){
			this.endingElem = this.currentElement;			
			for(var i = 0; i < this.options.elemsSlide; i++ ){
				this.endingElem += direction;
				if( this.endingElem >= this.totalElements ) this.endingElem = 0;
				if( this.endingElem < 0 ) this.endingElem = this.totalElements-1;
			}
		}	
		
		var s = new Hash();
		var fxDist = 0;
		if( this.options.slideVertical ){
			s.include('margin-top', -this.elementHeight);
			fxDist = this.direction == 1 ? -this.elementHeight : 0;
		}else{
			s.include('margin-left', -this.elementWidth);
			fxDist = this.direction == 1 ? -this.elementWidth : 0;
		}
		
		if( this.direction == -1 ){
			this.rearange();
			$(this.options.thumbsContainer).setStyles(s);			
		}
		this.started = true;
		
		this.myFx.start( fxDist ).chain( function(){			
			this.rearange(true);			
			if(this.options.elemsSlide){
				if( this.endingElem !== this.currentElement ){ 
					if( this.options.autoSlide )
						this.stopAutoSlide();
					this.slide(this.direction);
				}
				else {
					if( this.options.autoSlide )
						this.startAutoSlide();
					this.endingElem = null;
				}
			}
		}.bind(this)  );
		
		this.fireEvent('onChange', currentIndex);
		
	},
	/* rearanges elements for continuous navigation */
	rearange: function( rerun ){
		
		if(rerun) this.started = false;
		if( rerun && this.direction == -1 ) return;
		
		this.currentElement = this.currentIndex( this.direction );
		
		var s = new Hash();
		if( this.options.slideVertical ) s.include('margin-top', 0);
		else s.include('margin-left', 0);
		
		$(this.options.thumbsContainer).setStyles(s);
		
		if( this.currentElement == 1 && this.direction == 1 ){
			this.elements[0].injectAfter(this.elements[this.totalElements-1]);
			return;
		}
		if( (this.currentElement == 0 && this.direction ==1) || (this.direction==-1 && this.currentElement == this.totalElements-1) ){
			this.rearrangeElement( this.elements.getLast(), this.direction == 1 ? this.elements[this.totalElements-2] : this.elements[0]);
			return;
		}
		
		if( this.direction == 1 ) this.rearrangeElement( this.elements[this.currentElement-1], this.elements[this.currentElement-2]);
		else this.rearrangeElement( this.elements[this.currentElement], this.elements[this.currentElement+1]);			
	},
	/* rearanges a single element for continuous navigation */
	rearrangeElement: function( element , indicator ){
		this.direction == 1 ? element.injectAfter(indicator) : element.injectBefore(indicator);
	},
	/* determines the current index in element list */
	currentIndex: function(){
		var elemIndex = null;
		switch( this.direction ){
			/* forward */
			case 1:
				elemIndex = this.currentElement >= this.totalElements-1 ? 0 : this.currentElement + this.direction;				
			break;
			/* backwards */
			case -1:
				elemIndex = this.currentElement == 0 ? this.totalElements - 1 : this.currentElement + this.direction;
			break;
		}
		return elemIndex;
	},
	/* starts auto sliding */
	startAutoSlide: function(){
		this.startIt = this.slide.bind(this).pass(this.direction|1);
		this.autoSlide = this.startIt.periodical(this.autoSlideTotal, this);
		this.isRunning = true;
		this.elements.addEvents({
			'mouseenter':function(){
				$clear(this.autoSlide);
				this.isRunning = false;
			}.bind(this),
			'mouseleave':function(){
				this.autoSlide = this.startIt.periodical(this.autoSlideTotal, this);
				this.isRunning = true;
			}.bind(this)
		})
	},
	/* stops auto sliding */
	stopAutoSlide: function(){
		$clear(this.autoSlide);
		this.isRunning = false;
	}
})