/*
Yetii - Yet (E)Another Tab Interface Implementation
version 1.7
http://www.kminek.pl/lab/yetii/
Copyright (c) Grzegorz Wojcik
Code licensed under the BSD License:
http://www.kminek.pl/bsdlicense.txt
*/

function Yetii() {

    this.defaults = {
        id: null,
        active: 1,
        interval: null,
        wait: null,
        persist: null,
        tabclass: 'tab',
        activeclass: 'active',
        callback: null,
        leavecallback: null

    };

    this.activebackup = null;

    for (var n in arguments[0]) {
        this.defaults[n]=arguments[0][n];
    };

    this.getTabs = function() {
        var retnode = [];
        var elem = document.getElementById(this.defaults.id).getElementsByTagName('*');
        var regexp = new RegExp("(^|\\s)" + this.defaults.tabclass.replace(/\-/g, "\\-") + "(\\s|$)");
        for (var i = 0; i < elem.length; i++) {
            if (regexp.test(elem[i].className)) retnode.push(elem[i]);
        }
        return retnode;
    };

    this.links = document.getElementById(this.defaults.id + '-nav').getElementsByTagName('a');
    this.listitems = document.getElementById(this.defaults.id + '-nav').getElementsByTagName('li');

    this.show = function(number) {
        for (var i = 0; i < this.tabs.length; i++) {
            this.tabs[i].style.display = ((i+1)==number) ? 'block' : 'none';
            if ((i+1)==number) {
                this.addClass(this.links[i], this.defaults.activeclass);
                this.addClass(this.listitems[i], this.defaults.activeclass + 'li');
            } else {
                this.removeClass(this.links[i], this.defaults.activeclass);
                this.removeClass(this.listitems[i], this.defaults.activeclass + 'li');
            }
        }
        if (this.defaults.leavecallback && (number != this.activebackup)) this.defaults.leavecallback(this.defaults.active);
        this.activebackup = number;
        this.defaults.active = number;
        if (this.defaults.callback) this.defaults.callback(number);
    };

    this.rotate = function(interval) {
        this.show(this.defaults.active);
        this.defaults.active++;
        if (this.defaults.active > this.tabs.length) this.defaults.active = 1;
        var self = this;
        if (this.defaults.wait) clearTimeout(this.timer2);
        this.timer1 = setTimeout(function(){
            self.rotate(interval);
        }, interval*1000);
    };

    this.next = function() {
        var _target = (this.defaults.active + 1 > this.tabs.length) ? 1 : this.defaults.active + 1;
        this.show(_target);
        this.defaults.active = _target;
    };

    this.previous = function() {
        var _target = ((this.defaults.active - 1) == 0) ? this.tabs.length : this.defaults.active - 1;
        this.show(_target);
        this.defaults.active = _target;
    };

    this.previous = function() {
        this.defaults.active--;
        if(!this.defaults.active) this.defaults.active = this.tabs.length;
        this.show(this.defaults.active);
    };

    this.gup = function(name) {
        name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");
        var regexS = "[\\?&]"+name+"=([^&#]*)";
        var regex = new RegExp( regexS );
        var results = regex.exec( window.location.href );
        if (results == null) return null;
        else return results[1];
    };

    this.parseurl = function(tabinterfaceid) {
        var result = this.gup(tabinterfaceid);
        if (result==null) return null;
        if (parseInt(result)) return parseInt(result);
        if (document.getElementById(result)) {
            for (var i=0;i<this.tabs.length;i++) {
                if (this.tabs[i].id == result) return (i+1);
            }
        }
        return null;
    };

    this.createCookie = function(name,value,days) {
        if (days) {
            var date = new Date();
            date.setTime(date.getTime()+(days*24*60*60*1000));
            var expires = "; expires="+date.toGMTString();
        }
        else var expires = "";
        document.cookie = name+"="+value+expires+"; path=/";
    };

    this.readCookie = function(name) {
        var nameEQ = name + "=";
        var ca = document.cookie.split(';');
        for(var i=0;i < ca.length;i++) {
            var c = ca[i];
            while (c.charAt(0)==' ') c = c.substring(1,c.length);
            if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
        }
        return null;
    };

    this.hasClass = function(el, className){
        var classes = el.className.split(' ');
        for (var i = 0; i < classes.length; i++) {
            if (classes[i] == className) return true;
        }
        return false;
    };

    this.addClass = function(el, className){
        if (!this.hasClass(el, className)) el.className = (el.className + ' ' + className).replace(/\s{2,}/g, ' ').replace(/^\s+|\s+$/g, '');
    };

    this.removeClass = function(el, className){
        el.className = el.className.replace(new RegExp('(^|\\s)' + className + '(?:\\s|$)'), '$1');
        el.className.replace(/\s{2,}/g, ' ').replace(/^\s+|\s+$/g, '');
    };

    this.tabs = this.getTabs();
    this.defaults.active = (this.parseurl(this.defaults.id)) ? this.parseurl(this.defaults.id) : this.defaults.active;
    if (this.defaults.persist && this.readCookie(this.defaults.id)) this.defaults.active = this.readCookie(this.defaults.id);
    this.activebackup = this.defaults.active;
    this.show(this.defaults.active);

    var self = this;
    for (var i = 0; i < this.links.length; i++) {
        this.links[i].customindex = i+1;
        this.links[i].onclick = function(){

            if (self.timer1) clearTimeout(self.timer1);
            if (self.timer2) clearTimeout(self.timer2);

            self.show(this.customindex);
            if (self.defaults.persist) self.createCookie(self.defaults.id, this.customindex, 0);

            if (self.defaults.wait) self.timer2 = setTimeout(function(){
                self.rotate(self.defaults.interval);
            }, self.defaults.wait*1000);

            return false;
        };
    }

    if (this.defaults.interval) this.rotate(this.defaults.interval);

};