var timer = null;
var offset = 5000;
var index = 0;

//´óͼ½»ÌæÂÖ»»
function slideImage(i)
{
 var id = 'image_'+ target[i];
 $('#'+ id)
 .animate({opacity: 1}, 800, function(){
  $(this).find('.word').animate({height: 'show'}, 'slow');
 }).show()
 .siblings(':visible')
 .find('.word').animate({height: 'hide'},'fast',function(){
 $(this).parent().animate({opacity: 0}, 800).hide();
 });
}
//bind thumb a
function hookThumb()
{    
 $('#Thumbs li a')
 .bind('click', function(){
 if(timer)
 {
  clearTimeout(timer);
 }                
  var id = this.id;            
  index = getIndex(id.substr(6));
  rechange(index);
  slideImage(index); 
  timer = window.setTimeout(auto, offset);  
  this.blur();            
  return false;
 });
}
//bind next/prev img
function hookBtn()
{
 $('#Thumbs li img').filter('#playprev,#playnext')
 .bind('click', function(){
 if(timer)
 {
  clearTimeout(timer);
 }
 var id = this.id;
 if(id == 'playprev') 
 {
  index--;
  if(index < 0) index = 3;
 }
 else
 {
  index++;
  if (index > 3) index = 0;
 }
 rechange(index);
 slideImage(index);
 timer = window.setTimeout(auto, offset);
 });
}
//get index
function getIndex(v)
{
 for(var i=0; i < target.length; i++)
 {
  if (target[i] == v) return i;
 }
}
function rechange(loop)
{
 var id = 'Thumb_'+ target[loop];
 $('#Thumbs li a.current').removeClass('current');
 $('#'+ id).addClass('current');
}
function auto()
{
 index++;
 if (index > 3)
 {
  index = 0;
 }
 rechange(index);
 slideImage(index);
 timer = window.setTimeout(auto, offset);
}
$(function()
{    
 //change opacity
 $('div.word').css({opacity: 0.85});
 auto();  
 hookThumb(); 
 hookBtn();
});