/**
 * @author Ryan Johnson <ryan@livepipe.net>
 * @copyright 2007 LivePipe LLC
 * @package Control.Tabs
 * @license MIT
 * @url http://livepipe.net/projects/control_tabs/
 * @version 1.6.0
 */

if(typeof(Control) == "undefined")
    var Control = {};
Control.Tabs = Class.create();
Object.extend(Control.Tabs,{
    tabs: $A([]),
    responders: $A([]),
    addResponder: function(responder){
        Control.Tabs.responders.push(responder);
    },
    removeResponder: function(responder){
        Control.Tabs.responders = Control.Tabs.responders.without(responder);
    },
    notifyResponders: function(event_name,argument_one,argument_two){
        Control.Tabs.responders.each(function(responder){
            if(responder[event_name])
                responder[event_name](argument_one,argument_two);
        });
    },
    findByTabId: function(id){
        return this.tabs.find(function(tab){
            return tab.links.find(function(link){
                return link.key == id;
            });
        });
    }
});
Object.extend(Control.Tabs.prototype,{
    activeContainer: false,
    activeLink: false,
    initialize: function(tab_set,options){
        Control.Tabs.tabs.push(this);
        tab_set = $(tab_set);
        this.options = $H({
            beforeChange: Prototype.emptyFunction,
            afterChange: Prototype.emptyFunction,
            linkSelector: 'li a',
            activeClassName: 'active',
            defaultTab: 'first',
            autoLinkExternal: true
        });
        if(options)
            for(o in options)
                this.options[o] = options[o];
        this.containers = $H({});
        this.links = (typeof(this.options.linkSelector == "string")
            ? tab_set.getElementsBySelector(this.options.linkSelector)
            : this.options.linkSelector(tab_set)
        ).findAll(function(link){return (/^#/).exec(link.href.replace(window.location.href.split('#')[0],''));});
        this.links.each(function(link){
            link.key = $A(link.getAttribute('href').replace(window.location.href.split('#')[0],'').split('/')).last().replace(/#/,'');
            this.containers[link.key] = $(link.key);
            link.onclick = function(link){
                this.setActiveTab(link);
                return false;
            }.bind(this,link);
        }.bind(this));
        if(this.options.defaultTab == 'first')
            this.setActiveTab(this.links.first());
        else if(this.options.defaultTab == 'last')
            this.setActiveTab(this.links.last());
        else
            this.setActiveTab(this.options.defaultTab);
        target_regexp = /#(.+)$/;
        targets = target_regexp.exec(window.location);
        if(targets && targets[1]){
            $A(targets[1].split(',')).each(function(target){
                this.links.each(function(target,link){
                    if(link.key == target){
                        this.setActiveTab(link);
                        throw $break;
                    }
                }.bind(this,target));
            }.bind(this));
        }
        if(this.options.autoLinkExternal){
            $A(document.getElementsByTagName('a')).each(function(a){
                if(!this.links.include(a)){
                    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));
        }
    },
    setActiveTab: function(link){
        if(typeof(link) == "undefined" || link == false)
            return;
        if(typeof(link) == "string"){
            this.links.each(function(_link){
                if(_link.key == link){
                    this.setActiveTab(_link);
                    throw $break;
                }
            }.bind(this));
        }else{
            this.containers.each(function(item){
                item[1].hide();
            });         
            this.links.each(function(item){
                item.removeClassName(this.options.activeClassName);
            }.bind(this));
            link.addClassName(this.options.activeClassName);
            this.options.beforeChange(this,this.activeContainer);
            Control.Tabs.notifyResponders('beforeChange',this,this.activeContainer);
            this.activeContainer = this.containers[link.key];
            this.activeLink = link;
            this.containers[link.key].show();
            this.options.afterChange(this,this.containers[link.key]);
            Control.Tabs.notifyResponders('afterChange',this,this.containers[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());
    }
});