var SL_Slider = new Class({

	//implements
	Implements: [Options],	

	//variables setup
	numNav: 		new Array(),		// will store number nav elements (if used)
	timer: 		null,			// periodical function variable holder
	isSliding: 	0,				// flag for animation/click prevention
	direction: 	1,				// flag for direction (forward/reverse)

	//options
	options: {

		slideTimer:		10000,  		//Time between slides (1 second = 1000), a.k.a. the interval duration
		isPaused:			false,		//flag for paused state
		transitionTime:	1100, 		//Transition time (1 second = 1000)
		transitionType:	'cubic:out',	//Transition type
		container:		null,		//container element
		items: 			null, 		//Array of elements for sliding
		itemNum:			0,			//Current item number
		numNavActive:		false,		//Whether or not the number navigation will be used
		numNavHolder:		null,		//Element that holds the number navigation
		playBtn:			null,		//Play (and pause) button element
		prevBtn:			null,		//Previous button element
		nextBtn:			null,		//Next button element
		NewsContainer:		'news'		// ID of the container that hold the news slider

	},

	//initialization
	initialize: function(options) {

		var self = this;

		//set options
		this.setOptions(options);
		
		if( $( this.options.NewsContainer ) ) {
			
			//remove any scrollbar(s) on the container
			self.options.container.setStyle('overflow', "hidden");  
	
			//if there is a play/pause button, set up functionality for it
			if(self.options.playBtn != null) {
				//self.pauseIt();  
				self.options.playBtn.set('text', 'pause');
				self.options.playBtn.addEvents({
					'click': 		function() { self.pauseIt(); },				
					'mouseenter' : function() { this.setStyle('cursor', 'pointer'); },
					'mouseleave' : function() {}
				});
			}
	
			//if there is a prev & next button, set up functionality for them
			if(self.options.prevBtn && self.options.nextBtn){
				self.options.prevBtn.addEvents({ 
					'click' :		function() {
									if(self.isSliding == 0){
										if(self.options.isPaused == false){
											$clear(self.timer);
											self.timer = self.slideIt.periodical(self.options.slideTimer, self, null);
										}
										self.direction = 0;
										self.slideIt();
									}
								},
					'mouseenter' :	function() { this.setStyle('cursor', 'pointer'); },
					'mouseleave' : function() {}
	
				});	
	
				this.options.nextBtn.addEvents({ 
					'click' :		function() {
									if(self.isSliding == 0){
										if(self.options.isPaused == false){
											$clear(self.timer);
											self.timer = self.slideIt.periodical(self.options.slideTimer, self, null);
										}
										self.direction = 1;
										self.slideIt();
									}
								},
					'mouseenter' :	function() { this.setStyle('cursor', 'pointer');},
					'mouseleave' : function() {}
				});	
	
			}
	
			//setup items (a.k.a. slides) from list
			self.options.items.each(function(el, i){
				  //f.y.i.  el = the element, i = the index
				  el.setStyle('position', "absolute");
				  var itemH = el.getSize().y;
				  var itemW = el.getSize().x;
				 //el.setStyle('top', (-1 * itemH));  //would use this if doing vertical transition
				  el.setStyle('left', (-1 * itemW));
	
				// -- Number nav setup
				if(self.options.numNavActive == true){
					//create numbered navigation boxes, and insert into the 'num_nav' ul)
					var numItem = new Element('li', {id: 'num'+i});
					var numLink = new Element('a', {
						'class': 	'numbtn',
						'html': 	(i+1)
					});
					numItem.adopt(numLink);
					self.options.numNavHolder.adopt(numItem);
					self.numNav.push(numLink);
					numLink.set('morph', {duration: 100, transition: Fx.Transitions.linear, link: 'ignore'});
					numLink.addEvents({
						'click' : 	function(){ self.numPress(i); },
						'mouseenter' : function() { this.setStyle('cursor', 'pointer'); }
					});
	
					//set initial number to active state
					if(i == self.options.itemNum){
						var initNum = self.numNav[i];
						initNum.addClass('active');
					}
	
				}
	
				//end if num nav 'active'
	
			 });

		}

	},

	//startup method
	start: function() {

		if( $( this.options.NewsContainer ) ) {
	
			var self = this;
			self.slideIt(self.options.itemNum);  //initialize first slide
			if(self.options.isPaused == false) {
				self.timer = self.slideIt.periodical(self.options.slideTimer, self, null);
				if(self.options.playBtn) self.options.playBtn.set('text', 'pause');
			} else {
				//self.pauseIt();
				if(self.options.playBtn) self.options.playBtn.set('text', 'play');
			}
		
		}
		
	},

	slideIt: function(passedID) {

		var self = this;
		//get item to slide out
		var curItem = self.options.items[self.options.itemNum]; 
		if(self.options.numNavActive == true){
			var curNumItem =  self.numNav[self.options.itemNum];
		}

		//check for passedID presence
		if(passedID != null) {
			if(self.options.itemNum != passedID){
				if(self.options.itemNum > passedID) { 
					self.direction = 0; 
				} else { 
					self.direction = 1;
				}
				self.options.itemNum = passedID;
			}
		} else {
			self.changeIndex();	
		}

		//now get item to slide in using new index
		var newItem = self.options.items[self.options.itemNum];
		if(self.direction == 0){
			var curX = self.options.container.getSize().x;
			var newX = (-1 * newItem.getSize().x);
		} else {
			var curX = (-1 * self.options.container.getSize().x);	
			var newX = newItem.getSize().x;
		}

		//add/remove active number's highlight
		if(self.options.numNavActive == true){
			var newNumItem =  self.numNav[self.options.itemNum];
			newNumItem.addClass('active');
		}

		//set up our animation stylings
		var item_in = new Fx.Morph(newItem, {
		     duration: 	self.options.transitionTime, 
		     transition: 	self.options.transitionType,
		     link: 		'ignore',
		     onStart: 		function(){ self.isSliding = 1; }, // prevents extra clicks
		     onComplete: 	function(){ self.isSliding = 0; }  // prevents extra clicks
		});

		item_in.start({
			//'opacity':[0,1],
			'left' : [newX, 0]
		});

		if(curItem != newItem){
			var item_out = new Fx.Morph(curItem, {
				     duration: 	self.options.transitionTime, 
				     transition: 	self.options.transitionType,
				     link: 		'ignore'
			});
			if(self.options.numNavActive == true){
				curNumItem.removeClass('active');
			}
			item_out.start({
				//'opacity':[0],
				'left' : [(curX)]
			});
		}
	},

	//--------------------------------------------------------------------------------------------------------

	//supplementary functions  (mini-functions)

	//--------------------------------------------------------------------------------------------------------

	pauseIt: function () {

		var self = this;
		//only move if not currently moving
		if(self.isSliding == 0) {
			if(self.options.isPaused == false) {
				self.options.isPaused = true;
				$clear(self.timer);
				self.options.playBtn.set('text', 'play');				
			} else {
				self.options.isPaused = false;
				self.slideIt();
				self.timer = self.slideIt.periodical(self.options.slideTimer, this, null); 
				self.options.playBtn.set('text', 'pause');
			}
		} //end if not sliding

	},

	changeIndex: function() {

		var self = this; 
		var numItems = self.options.items.length;  //get number of slider items

		//change index based on value of 'direction' parameter
		if(self.direction == 1) {
			if(self.options.itemNum < (numItems - 1)){
				self.options.itemNum++; 
			} else {
				self.options.itemNum = 0;
			}

		} else if(self.direction == 0) {
			if(self.options.itemNum > 0) {
				self.options.itemNum--; 
			} else {
				self.options.itemNum = (numItems - 1);
			}
		}	
	},

	numPress: function (theIndex) {
		
		var self = this;
		if((self.isSliding == 0) && (self.options.itemNum != theIndex)){
			if(self.options.isPaused == false){
				$clear(self.timer);
				self.timer = self.slideIt.periodical(self.options.slideTimer, this, null);
			}
			self.slideIt(theIndex);
		}

	}

	//------------------------  end supp. functions -----------------------------------------//

});