/**
 * SimpleTabs - Unobtrusive Tabs with Ajax
 *
 * @example
 *
 *	var tabs = new SimpleTabs($('tab-element'), {
 * 		selector: 'h2.tab-tab'
 *	});
 *
 * @version		1.0
 *
 * @license		MIT License
 * @author		Harald Kirschner <mail [at] digitarald.de>
 * @copyright	2007 Author
 */

var selectedTab = Cookie.read('selectedTab');
if (!selectedTab) { selectedTab = 0; };

var SimpleTabs = new Class({

	Implements: [Events, Options],

	/**
	 * Options
	 */
	options: {
		show: selectedTab,
		tabKeyword: 'tab-',
		selector: '.tab-tab',
		classWrapper: 'TabbedPanelsContentGroup',
		classMenu: 'TabbedPanelsTabGroup',
		classContainer: 'TabbedPanelsContent',
		onSelect: function(toggle, container, index) {
			toggle.addClass('tab-selected');
			container.setStyle('display', '');
		},
		onDeselect: function(toggle, container, index) {
			toggle.removeClass('tab-selected');
			container.setStyle('display', 'none');
		},
		onRequest: function(toggle, container, index) {
			container.addClass('tab-ajax-loading');
		},
		onComplete: function(toggle, container, index) {
			container.removeClass('tab-ajax-loading');
		},
		onFailure: function(toggle, container, index) {
			container.removeClass('tab-ajax-loading');
		},
		onAdded: Class.empty,
		getContent: null,
		ajaxOptions: {},
		cache: true
	},

	/**
	 * Constructor
	 *
	 * @param {Element} The parent Element that holds the tab elements
	 * @param {Object} Options
	 */
	initialize: function(element, options) {
		this.element = $(element);
		this.setOptions(options);
		this.selected = null;
		this.getSelectedTab();
		this.build();
	},

	build: function() {
		var firstNonLinkedTab;
		this.tabs = [];
		this.menu = new Element('ul', {'class': this.options.classMenu});
		this.wrapper = new Element('div', {'class': this.options.classWrapper});

		this.element.getElements(this.options.selector).each(function(el) {
			var content = el.get('href') || (this.options.getContent ? this.options.getContent.call(this, el) : el.getNext());
			if (el.firstChild.nodeName == "A") {
				this.addTab(el.innerHTML, el.title || el.innerHTML, content, true);
			}
			else {
				if(firstNonLinkedTab == undefined && this.tabs.length != undefined) firstNonLinkedTab = this.tabs.length;
				this.addTab(el.innerHTML, el.title || el.innerHTML, content, false);
			}
		}, this);
		this.element.empty().adopt(this.menu, this.wrapper);
		if(firstNonLinkedTab) this.options.show = firstNonLinkedTab;
		if (this.tabs.length) this.select(this.options.show);
	},

	/**
	 * Get selected tab by href
	 */
	getSelectedTab: function() {
		var href = top.location.href;
		var pos = href.indexOf('#' + this.options.tabKeyword) + 1;
		return ( this.options.show = (pos) ? href.substr(pos + this.options.tabKeyword.length) : 0 );
	},
 
	/**
	 * Set selected tab to href
	 *
	 * @param {Int} index of selected Tab
	 */
	setSelectedTab: function( index ) {
		if ( ! this.options.tabKeyword.length )
			return;
 
		if ( 0 <= this.selected && top.location.href.contains('#' + this.options.tabKeyword) ) {
			var rxp = new RegExp('#' + this.options.tabKeyword + this.selected, 'g');
			top.location.href = top.location.href.replace(rxp, '#' + this.options.tabKeyword + index);
		}; // endif
	},

	/**
	 * Add a new tab at the end of the tab menu
	 *
	 * @param {String} inner Text
	 * @param {String} Title
	 * @param {Element|String} Content Element or URL for Ajax
	 */
	addTab: function(text, title, content, link) {
		var grab = $(content);
		var container = (grab || new Element('div'))
			.setStyle('display', 'none')
			.addClass(this.options.classContainer)
			.inject(this.wrapper);
		var pos = this.tabs.length;
		var evt = (this.options.hover) ? 'mouseenter' : 'click';
		if (link) {
			var tab = {
				container: container,
				toggle: new Element('li', {html: text}).inject(this.menu)
			};
		} else	{
			var tab = {
				container: container,
				toggle: new Element('li').grab(new Element('a', {
					href: '#' + (this.options.tabKeyword.length ? (this.options.tabKeyword + pos) : ''),
					html: text
				})).addEvent(evt, this.onClick.bindWithEvent(this, [pos])).inject(this.menu)
			};
		}
		if (!grab && $type(content) == 'string') tab.url = content;
		this.tabs.push(tab);
		return this.fireEvent('onAdded', [tab.toggle, tab.container, pos]);
	},

	onClick: function(evt, index) {
		this.select(index);
		return false;
	},

	/**
	 * Select the tab via tab-index
	 *
	 * @param {Number} Tab-index
	 */
	select: function(index) {
		var cookie = Cookie.write('selectedTab', index, {duration: 30});
		if (this.selected === index || !this.tabs[index]) return this;
		if (this.ajax) this.ajax.cancel().removeEvents();
		var tab = this.tabs[index];
		var params = [tab.toggle, tab.container, index];
		if (this.selected !== null) {
			var current = this.tabs[this.selected];
			if (this.ajax && this.ajax.running) this.ajax.cancel();
			params.extend([current.toggle, current.container, this.selected]);
			this.fireEvent('onDeselect', [current.toggle, current.container, this.selected]);
		}
		this.fireEvent('onSelect', params);
		if (tab.url && (!tab.loaded || !this.options.cache)) {
			this.ajax = this.ajax || new Request.HTML();
			this.ajax.setOptions({
				url: tab.url,
				method: 'get',
				update: tab.container,
				onFailure: this.fireEvent.pass(['onFailure', params], this),
				onComplete: function(resp) {
					tab.loaded = true;
					this.fireEvent('onComplete', params);
				}.bind(this)
			}).setOptions(this.options.ajaxOptions);
			this.ajax.send();
			this.fireEvent('onRequest', params);
		}
		this.setSelectedTab(index);
		this.selected = index;
		return this;
	}

});