function $(id) { return document.getElementById(id);}

function addLoadEvent(func){
 var oldonload = window.onload;
 if (typeof window.onload != 'function') {
 window.onload = func;
 } else {
 window.onload = function(){
 oldonload();
 func();
 }
 }
}

function addBtn() {
 if(!$('focus_turn')) return;
 var focusList = $('focus_turn').getElementsByTagName('li');
 var btnBox = document.createElement('focus_btn');
 btnBox.setAttribute('id','focus_btn');
 var SpanBox ='';
 for(var i=1;i<=focusList.length;i++ ) {
 var spanList = '<span class="normal">'+i+'</span>';
 SpanBox += spanList;
 }
 btnBox.innerHTML = SpanBox;
 $('focus_turn').appendChild(btnBox);
 $('focus_btn').getElementsByTagName('span')[0].className = 'current';
}

function classNormal(){
 var focusList = $('focus_turn').getElementsByTagName('li');
 var btnList = $('focus_btn').getElementsByTagName('span');
 for(var i=0;i<focusList.length;i++) {
 focusList[i].className='normal';
 btnList[i].className='normal';
 }
}

function classCurrent(n){
 var focusList = $('focus_turn').getElementsByTagName('li');
 var btnList = $('focus_btn').getElementsByTagName('span');
 focusList[n].className='current';
 btnList[n].className='current';
}

var autoKey = false;
function btnTurn() {
 if(!$('focus_turn')) return;
 $('focus_turn').onmouseover = function(){autoKey = true};
 $('focus_turn').onmouseout = function(){autoKey = false};
 var focusList = $('focus_turn').getElementsByTagName('li');
 var btnList = $('focus_btn').getElementsByTagName('span');
 for (var m=0;m<btnList.length;m++){
 btnList[m].onmouseover = function() {
 classNormal();
 this.className='current';
 var n=this.childNodes[0].nodeValue-1;
 focusList[n].className='current';
 }
 }
}

setInterval('autoTurn()', 5000);
function autoTurn() {
 if(!$('focus_turn')) return;
 if (autoKey) return;
 var focusList = $('focus_turn').getElementsByTagName('li');
 var btnList = $('focus_btn').getElementsByTagName('span');
 for(var i=0;i<focusList.length;i++) {
 if (focusList[i].className == 'current') {
 var currentNum = i;
 }
 }
 if (currentNum==focusList.length-1 ){
 classNormal();
 classCurrent(0);
 } else {
 classNormal();
 classCurrent(currentNum+1);
 }

}
addLoadEvent(addBtn);
addLoadEvent(btnTurn);