/*
Yetii - Yet (E)Another Tab Interface Implementation
version 1.6
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.contains = function(el, item, from) {
    return el.indexOf(item, from) != -1;
  };

  this.hasClass = function(el, className){
    return this.contains(el.className, className, ' ');
  };

  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);

};