/**
 * @author Ryan Johnson <http://syntacticx.com/>
 * @copyright 2008 PersonalGrid Corporation <http://personalgrid.com/>
 * @package LivePipe UI
 * @license MIT
 * @url http://livepipe.net/control/tabs
 * @require prototype.js, livepipe.js
 */

if(typeof(Prototype) == "undefined")
        throw "Control.Tabs requires Prototype to be loaded.";
if(typeof(Object.Event) == "undefined")
        throw "Control.Tabs requires Object.Event to be loaded.";

Control.Tabs = Class.create({
        initialize: function(tab_list_container,options){
                if(!$(tab_list_container))
                        throw "Control.Tabs could not find the element: " + tab_list_container;
                this.activeContainer = false;
                this.activeLink = false;
                this.containers = $H({});
                this.links = [];
                Control.Tabs.instances.push(this);
                this.options = {
                        beforeChange: Prototype.emptyFunction,
                        afterChange: Prototype.emptyFunction,
                        hover: false,
                        linkSelector: 'li a',
                        setClassOnContainer: false,
                        activeClassName: 'active',
                        defaultTab: 'first',
                        autoLinkExternal: true,
                        targetRegExp: /#(.+)$/,
                        showFunction: Element.show,
                        hideFunction: Element.hide
                };
                Object.extend(this.options,options || {});
                (typeof(this.options.linkSelector == 'string')
                        ? $(tab_list_container).select(this.options.linkSelector)
                        : this.options.linkSelector($(tab_list_container))
                ).findAll(function(link){
                        return (/^#/).exec((Prototype.Browser.WebKit ? decodeURIComponent(link.href) : link.href).replace(window.location.href.split('#')[0],''));
                }).each(function(link){
                        this.addTab(link);
                }.bind(this));
                this.containers.values().each(Element.hide);
                if(this.options.defaultTab == 'first')
                        this.setActiveTab(this.links.first());
                else if(this.options.defaultTab == 'last')
                        this.setActiveTab(this.links.last());
                else
                        this.setActiveTab(this.options.defaultTab);
                var targets = this.options.targetRegExp.exec(window.location);
                if(targets && targets[1]){
                        targets[1].split(',').each(function(target){
                                this.setActiveTab(this.links.find(function(link){
                                        return link.key == target;
                                }));
                        }.bind(this));
                }
                if(this.options.autoLinkExternal){
                        $A(document.getElementsByTagName('a')).each(function(a){
                                if(!this.links.include(a)){
                                        var clean_href = a.href.replace(window.location.href.split('#')[0],'');
                                        if(clean_href.substring(0,1) == '#'){
                                                if(this.containers.keys().include(clean_href.substring(1))){
                                                        $(a).observe('click',function(event,clean_href){
                                                                this.setActiveTab(clean_href.substring(1));
                                                        }.bindAsEventListener(this,clean_href));
                                                }
                                        }
                                }
                        }.bind(this));
                }
        },
        addTab: function(link){
                this.links.push(link);
                link.key = link.getAttribute('href').replace(window.location.href.split('#')[0],'').split('/').last().replace(/#/,'');
                var container = $(link.key);
                if(!container)
                        throw "Control.Tabs: #" + link.key + " was not found on the page."
                this.containers.set(link.key,container);
                link[this.options.hover ? 'onmouseover' : 'onclick'] = function(link){
                        if(window.event)
                                Event.stop(window.event);
                        this.setActiveTab(link);
                        return false;
                }.bind(this,link);
        },
        setActiveTab: function(link){
                if(!link && typeof(link) == 'undefined')
                        return;
                if(typeof(link) == 'string'){
                        this.setActiveTab(this.links.find(function(_link){
                                return _link.key == link;
                        }));
                }else if(typeof(link) == 'number'){
                        this.setActiveTab(this.links[link]);
                }else{
                        if(this.notify('beforeChange',this.activeContainer,this.containers.get(link.key)) === false)
                                return;
                        if(this.activeContainer)
                                this.options.hideFunction(this.activeContainer);
                        this.links.each(function(item){
                                (this.options.setClassOnContainer ? $(item.parentNode) : item).removeClassName(this.options.activeClassName);
                        }.bind(this));
                        (this.options.setClassOnContainer ? $(link.parentNode) : link).addClassName(this.options.activeClassName);
                        this.activeContainer = this.containers.get(link.key);
                        this.activeLink = link;
                        this.options.showFunction(this.containers.get(link.key));
                        this.notify('afterChange',this.containers.get(link.key));
                }
        },
        next: function(){
                this.links.each(function(link,i){
                        if(this.activeLink == link && this.links[i + 1]){
                                this.setActiveTab(this.links[i + 1]);
                                throw $break;
                        }
                }.bind(this));
        },
        previous: function(){
                this.links.each(function(link,i){
                        if(this.activeLink == link && this.links[i - 1]){
                                this.setActiveTab(this.links[i - 1]);
                                throw $break;
                        }
                }.bind(this));
        },
        first: function(){
                this.setActiveTab(this.links.first());
        },
        last: function(){
                this.setActiveTab(this.links.last());
        }
});
Object.extend(Control.Tabs,{
        instances: [],
        findByTabId: function(id){
                return Control.Tabs.instances.find(function(tab){
                        return tab.links.find(function(link){
                                return link.key == id;
                        });
                });
        }
});
Object.Event.extend(Control.Tabs);