(function($) {

	// static constructs
	$.tools = $.tools || {version: '@VERSION'};

	$.tools.tabs = {

		conf: {
			tabs: 'a',
			current: 'current',
			onBeforeClick: null,
			onClick: null, 
			effect: 'default',
			initialIndex: 0,			
			event: 'click',
			rotate: false,

			// 1.2
			history: false
		},

		addEffect: function(name, fn) {
			effects[name] = fn;
		}

	};

	var effects = {

		// simple "toggle" effect
		'default': function(i, done) { 
			this.getPanes().hide().eq(i).show();
			done.call();
		}, 

		/*
			configuration:
				- fadeOutSpeed (positive value does "crossfading")
				- fadeInSpeed
		*/
		fade: function(i, done) {		

			var conf = this.getConf(),            
				 speed = conf.fadeOutSpeed,
				 panes = this.getPanes();

			if (speed) {
				panes.fadeOut(speed);	
			} else {
				panes.hide();	
			}

			panes.eq(i).fadeIn(conf.fadeInSpeed, done);	
		},

		// for basic accordions
		slide: function(i, done) {
			this.getPanes().slideUp(200);
			this.getPanes().eq(i).slideDown(400, done);			 
		}, 

		/**
		 * AJAX effect
		 */
		ajax: function(i, done)  {			
			this.getPanes().eq(0).load(this.getTabs().eq(i).attr("href"), done);	
		}		
	};   	

	var w;

	/**
	 * Horizontal accordion
	 * 
	 * @deprecated will be replaced with a more robust implementation
	 */
	$.tools.tabs.addEffect("horizontal", function(i, done) {

		// store original width of a pane into memory
		if (!w) { w = this.getPanes().eq(0).width(); }

		// set current pane's width to zero
		this.getCurrentPane().animate({width: 0}, function() { $(this).hide(); });

		// grow opened pane to it's original width
		this.getPanes().eq(i).animate({width: w}, function() { 
			$(this).show();
			done.call();
		});

	});	


	function Tabs(root, paneSelector, conf) {

		var self = this, 
			 trigger = root.add(this),
			 tabs = root.find(conf.tabs),
			 panes = paneSelector.jquery ? paneSelector : root.children(paneSelector),			 
			 current;


		// make sure tabs and panes are found
		if (!tabs.length)  { tabs = root.children(); }
		if (!panes.length) { panes = root.parent().find(paneSelector); }
		if (!panes.length) { panes = $(paneSelector); }


		// public methods
		$.extend(this, {				
			click: function(i, e) {

				var tab = tabs.eq(i);												 

				if (typeof i == 'string' && i.replace("#", "")) {
					tab = tabs.filter("[href*=" + i.replace("#", "") + "]");
					i = Math.max(tabs.index(tab), 0);
				}

				if (conf.rotate) {
					var last = tabs.length -1; 
					if (i < 0) { return self.click(last, e); }
					if (i > last) { return self.click(0, e); }						
				}

				if (!tab.length) {
					if (current >= 0) { return self; }
					i = conf.initialIndex;
					tab = tabs.eq(i);
				}				

				// current tab is being clicked
				if (i === current) { return self; }

				// possibility to cancel click action				
				e = e || $.Event();
				e.type = "onBeforeClick";
				trigger.trigger(e, [i]);				
				if (e.isDefaultPrevented()) { return; }

				// call the effect
				effects[conf.effect].call(self, i, function() {

					// onClick callback
					e.type = "onClick";
					trigger.trigger(e, [i]);					
				});			

				// default behaviour
				current = i;
				tabs.removeClass(conf.current);	
				tab.addClass(conf.current);				

				return self;
			},

			getConf: function() {
				return conf;	
			},

			getTabs: function() {
				return tabs;	
			},

			getPanes: function() {
				return panes;	
			},

			getCurrentPane: function() {
				return panes.eq(current);	
			},

			getCurrentTab: function() {
				return tabs.eq(current);	
			},

			getIndex: function() {
				return current;	
			}, 

			next: function() {
				return self.click(current + 1);
			},

			prev: function() {
				return self.click(current - 1);	
			},

			destroy: function() {
				tabs.unbind(conf.event).removeClass(conf.current);
				panes.find("a[href^=#]").unbind("click.T"); 
				return self;
			}

		});

		// callbacks	
		$.each("onBeforeClick,onClick".split(","), function(i, name) {

			// configuration
			if ($.isFunction(conf[name])) {
				$(self).bind(name, conf[name]); 
			}

			// API
			self[name] = function(fn) {
				if (fn) { $(self).bind(name, fn); }
				return self;	
			};
		});


		if (conf.history && $.fn.history) {
			$.tools.history.init(tabs);
			conf.event = 'history';
		}	

		// setup click actions for each tab
		tabs.each(function(i) { 				
			$(this).bind(conf.event, function(e) {
				self.click(i, e);
				return e.preventDefault();
			});			
		});

		// cross tab anchor link
		panes.find("a[href^=#]").bind("click.T", function(e) {
			self.click($(this).attr("href"), e);		
		}); 

		// open initial tab
		if (location.hash && conf.tabs == "a" && root.find("[href=" +location.hash+ "]").length) {
			self.click(location.hash);

		} else {
			if (conf.initialIndex === 0 || conf.initialIndex > 0) {
				self.click(conf.initialIndex);
			}
		}				

	}


	// jQuery plugin implementation
	$.fn.tabs = function(paneSelector, conf) {

		// return existing instance
		var el = this.data("tabs");
		if (el) { 
			el.destroy();	
			this.removeData("tabs");
		}

		if ($.isFunction(conf)) {
			conf = {onBeforeClick: conf};
		}

		// setup conf
		conf = $.extend({}, $.tools.tabs.conf, conf);		


		this.each(function() {				
			el = new Tabs($(this), paneSelector, conf);
			$(this).data("tabs", el); 
		});		

		return conf.api ? el: this;		
	};		

}) (jQuery);