var pbsObject = Class.create();
pbsObject.prototype = {

	head: null,
	id: null,
	activeImage: null,

	initialize: function() {
		this.id = 'pbs';
		this.activeImage = 0;
		this.images = 0;
		this.setupImages();
		this.buildNav();
	},
	
	buildNav: function() {
		var listElements = $('pbs').childElements();
		$('pbs-firstLink').observe('mouseover', function() { 
			pbs.goTo(1);
		});
		$('pbs-secondLink').observe('mouseover', function() {
			pbs.goTo(2);
		});
		$('pbs-firstLink').observe('mouseout', function() { 
			pbs.goTo(0);
		});
		$('pbs-secondLink').observe('mouseout', function() {
			pbs.goTo(0);
		});
	},
	
	goTo: function(image) {
		this.change(image);
	},
	
	change: function(image) {
		if(image != this.activeImage) {
			$('pbs_' + this.activeImage).setStyle({display: 'none'});
			$('pbs_' + image).setStyle({display: 'block'});
		}
		this.activeImage = image;
	},
	
	setupImages: function() {	
		var listElements = $(this.id).childElements();
		this.head = new Array(); 
		for (var i = 0; i < listElements.length; ++i) {
			if( i != 0) {
				listElements[i].setStyle ({ display: 'none' });
			}
			listElements[i].writeAttribute('id', 	this.id + '_' + i);
			this.head[i] = listElements[i].childElements()[1].innerHTML;
		}
		this.images = i;
	}
	
}