var YTabs = function(){
    var D = document, isString = function(s){
        return typeof s === 'string';
    }, IE = navigator.userAgent.match(/MSIE\s([^;]*)/);
    
    return {
        stopEvent: function(evt){
            this.stopPropagation(evt);
            this.preventDefault(evt);
        },
        stopPropagation: function(evt){
            if (evt.stopPropagation) {
                evt.stopPropagation();
            }
            else {
                evt.cancelBubble = true;
            }
        },
        preventDefault: function(evt){
            if (evt.preventDefault) {
                evt.preventDefault();
            }
            else {
                evt.returnValue = false;
            }
        },
        hasClass: function(elem, className){
            var has = new RegExp("(?:^|\\s+)" + className + "(?:\\s+|$)");
            return has.test(elem.className);
        },
        addClass: function(elem, className){
            if (this.hasClass(elem, className)) {
                return;
            }
            elem.className = [elem.className, className].join(" ");
        },
        removeClass: function(elem, className){
            var replace = new RegExp("(?:^|\\s+)" + className + "(?:\\s+|$)", "g");
            if (!this.hasClass(elem, className)) {
                return;
            }
            var o = elem.className;
            elem.className = o.replace(replace, " ");
            if (this.hasClass(elem, className)) {
                this.removeClass(elem, className);
            }
        },
        getByClassName: function(className, tag, rootTag){
            var elems = [], i, tempCnt = D.getElementById(rootTag).getElementsByTagName(tag), len = tempCnt.length;
            for (i = 0; i < len; i++) {
                if (YTabs.hasClass(tempCnt[i], className)) {
                    elems.push(tempCnt[i]);
                }
            }
            if (elems.length < 1) {
                return false;
            }
            else {
                return elems;
            }
        },
        tabs: function(){
            var j, len = arguments.length;
            for (j = 0; j < len; j += 1) {
                (function(config){
                    var tabCnt = (config.tabId) ? D.getElementById(config.tabId) : (config.tabRoot || null), tabs = (config.tTag) ? tabCnt.getElementsByTagName(config.tTag) : (config.tabs || null), contents = (config.cTag) ? tabCnt.getElementsByTagName(config.cTag) : (config.contents || null), defaultClass = config.defaultClass || 'current', defaultIndex = config.defaultIndex || 0, lastIndex = defaultIndex, previousClass = config.previousClass || '', previousClassTab = null, hideAll = config.hideAll || false, evtName = config.evt || 'mouseover', i = 0, length = tabs.length, lastTab = tabs[defaultIndex], lastTabClass = config.lastTabClass || '', lastContent = contents[defaultIndex], auto = config.auto || false, timer = null, speed = config.speed || 6000, isPause = false, fadeUp = config.fadeUp || false, currentImage = null, autoChange = function(){
                        if (!isPause) {
                            var currentContent = null, currentTab = null;
                            if (timer) {
                                clearTimeout(timer);
                            }
                            lastIndex = lastIndex + 1;
                            if (lastIndex === tabs.length) {
                                lastIndex = 0;
                            }
                            currentContent = contents[lastIndex];
                            currentTab = tabs[lastIndex];
                            if (fadeUp) {
                                currentImage = currentContent.getElementsByTagName('img')[0];
                                YTabs.fadeUp(currentImage);
                            }
                            YTabs.removeClass(lastTab, (YTabs.hasClass(lastTab, defaultClass) ? defaultClass : 'current'));
                            if (currentTab === tabs[defaultIndex]) {
                                YTabs.addClass(currentTab, defaultClass);
                            }
                            else {
                                YTabs.addClass(currentTab, 'current');
                            }
                            if (previousClass) {
                                if (previousClassTab) {
                                    YTabs.removeClass(previousClassTab, previousClass);
                                }
                                if (lastIndex !== 0) {
                                    YTabs.addClass(tabs[lastIndex - 1], previousClass);
                                    if ((lastIndex - 1) === defaultIndex) {
                                        YTabs.removeClass(tabs[lastIndex - 1], defaultClass);
                                    }
                                    previousClassTab = (tabs[lastIndex - 1]);
                                }
                            }
                            lastContent.style.display = "none";
                            currentContent.style.display = "block";
                            lastContent = currentContent;
                            lastTab = currentTab;
                            timer = setTimeout(autoChange, speed);
                        }
                        else {
                            timer = setTimeout(autoChange, speed);
                            return false;
                        }
                    };
                    if (tabs && contents) {
                        if (!hideAll) {
                            YTabs.addClass(lastTab, defaultClass);
                            lastContent.style.display = 'block';
                        }
                        else {
                            YTabs.removeClass(lastTab, defaultClass);
                            lastContent.style.display = 'none';
                        }
                        for (; i < length; i += 1) {
                            if (i !== defaultIndex) {
                                YTabs.removeClass(tabs[i], 'current');
                                contents[i].style.display = 'none';
                            }
                            tabs[i]['on' + evtName] = function(index){
                                return function(event){
                                    var evt = null, currentContent = contents[index];
                                    YTabs.removeClass(lastTab, (YTabs.hasClass(lastTab, defaultClass) ? defaultClass : 'current'));
                                    if (this === tabs[defaultIndex]) {
                                        YTabs.addClass(this, defaultClass);
                                    }
                                    else {
                                        YTabs.addClass(this, 'current');
                                    }
                                    if (previousClass) {
                                        if (previousClassTab) {
                                            YTabs.removeClass(previousClassTab, previousClass);
                                        }
                                        if (index !== 0) {
                                            YTabs.addClass(tabs[index - 1], previousClass);
                                            if ((index - 1) === defaultIndex) {
                                                YTabs.removeClass(tabs[index - 1], defaultClass);
                                            }
                                            previousClassTab = (tabs[index - 1]);
                                        }
                                    }
                                    lastContent.style.display = "none";
                                    currentContent.style.display = "block";
                                    lastContent = currentContent;
                                    lastTab = this;
                                    lastIndex = index;
                                    if (auto) {
                                        isPause = true;
                                    }
                                    if (fadeUp) {
                                        currentImage = contents[index].getElementsByTagName('img')[0];
                                        YTabs.fadeUp(currentImage);
                                    }
                                    if (evtName === 'click') {
                                        evt = event || window.event;
                                        YTabs.stopEvent(evt);
                                    }
                                }
                            }(i);
                            tabs[i]['onmouseout'] = function(index){
                                return function(){
                                    if (hideAll && evtName === 'mouseover') {
                                        if (lastTab === this) {
                                            YTabs.removeClass(this, (YTabs.hasClass(this, defaultClass) ? defaultClass : 'current'));
                                        }
                                        if (previousClassTab) {
                                            YTabs.removeClass(previousClassTab, previousClass);
                                        }
                                        contents[index].style.display = 'none';
                                    }
                                    else {
                                        if (auto) {
                                            isPause = false;
                                        }
                                    }
                                }
                            }(i);
                        }
                        if (auto) {
                            timer = setTimeout(autoChange, speed);
                        }
                    }
                })(arguments[j]);
            }
        },
        setOpacity: function(el, val){
            if (IE) {
                if (isString(el.style.filter)) {
                    el.style.filter = 'alpha(opacity=' + val * 100 + ')';
                    if (!el.currentStyle || !el.currentStyle.hasLayout) {
                        el.style.zoom = 1;
                    }
                }
            }
            else {
                el.style['opacity'] = val;
            }
        },
        fadeUp: function(elem){
            if (elem) {
                var level = 0, fade = function(){
                    level += 0.05;
                    if (timer) {
                        clearTimeout(timer);
                    }
                    if (level > 1) {
                        YTabs.setOpacity(elem, 1);
                        return false;
                    }
                    else {
                        YTabs.setOpacity(elem, level);
                    }
                    var timer = setTimeout(fade, 50);
                };
                fade();
            }
        },
        moveElement: function(element, final_x, final_y, speed){
            if (!D.getElementById) {
                return false;
            }
            var elem = (typeof element === 'string') ? D.getElementById(element) : element;
            var style = elem.style;
            if (timer) {
                clearTimeout(timer);
            }
            if (!style.left) {
                style.left = '0';
            }
            if (!style.top) {
                style.top = '0';
            }
            var xpos = parseInt(style.left, 10);
            var ypos = parseInt(style.top, 10);
            if (xpos == final_x && ypos == final_y) {
                return true;
            }
            if (xpos < final_x) {
                var dist = Math.ceil((final_x - xpos) / 10);
                xpos = xpos + dist;
            }
            if (xpos > final_x) {
                var dist = Math.ceil((xpos - final_x) / 10);
                xpos = xpos - dist;
            }
            if (ypos < final_y) {
                var dist = Math.ceil((final_y - ypos) / 10);
                ypos = ypos + dist;
            }
            if (ypos > final_y) {
                var dist = Math.ceil((ypos - final_y) / 10);
                ypos = ypos - dist;
            }
            style.left = xpos + 'px';
            style.top = ypos + 'px';
            var timer = setTimeout(function(){
                YTabs.moveElement(element, final_x, final_y, speed);
            }, speed);
        }
    };
}();