/*
Paulo Sergio Klaus
pauloklaus@yahoo.com.br
Março de 2008

Código simplificado a partir do script de Alf Magne Kalleland (post@dhtmlgoodies.com):
http://www.dhtmlgoodies.com/index.html?whichScript=image_slideshow
*/
var activeImage=false;
//var imageGalleryLeftPos=false;
var imageGalleryWidth=false;
var imageGalleryObj=false;
var maxGalleryXPos=false;
var slideSpeed=0;

function startSlide(e)
{
  if (document.all) e=event;
  var id=this.id;

  if (this.id=='album_direita')
  {
    slideSpeedMultiply=Math.floor((e.clientX-this.offsetLeft)/5);
    slideSpeed=-1*slideSpeedMultiply;
    slideSpeed=Math.max(-10,slideSpeed);
  }
  else
  {			
    slideSpeedMultiply=10-Math.floor((e.clientX-this.offsetLeft)/5);
    slideSpeed=1*slideSpeedMultiply;
    slideSpeed=Math.min(10,slideSpeed);
    if (slideSpeed<0) slideSpeed=10;
  }
}

function releaseSlide()
{
  var id=this.id;
  slideSpeed=0;
}
  
function gallerySlide()
{
  if (slideSpeed!=0)
  {
    var leftPos=imageGalleryObj.offsetLeft;
    leftPos=leftPos/1+slideSpeed;
    if (leftPos>maxGalleryXPos)
    {
      leftPos=maxGalleryXPos;
      slideSpeed=0;
    }
    if (leftPos<minGalleryXPos)
    {
      leftPos=minGalleryXPos;
      slideSpeed=0;
    }
    imageGalleryObj.style.left=leftPos+'px';
  }
  setTimeout('gallerySlide()',20);
}

function showImage()
{
  if (activeImage)
  {
    activeImage.style.filter='alpha(opacity=50)';	
    activeImage.style.opacity=0.5;
  }
  this.style.filter='alpha(opacity=100)';
  this.style.opacity=1;	
  activeImage=this;
  /* PERSONALIZADO */
  document.getElementById("album_foto").src=this.src;
}

function initSlideShow()
{
  document.getElementById('album_esquerda').onmousemove=startSlide;
  document.getElementById('album_esquerda').onmouseout=releaseSlide;
  document.getElementById('album_direita').onmousemove=startSlide;
  document.getElementById('album_direita').onmouseout=releaseSlide;
  
  imageGalleryObj=document.getElementById('album_miniaturas');
  //imageGalleryLeftPos=imageGalleryObj.offsetLeft;
  imageGalleryWidth=document.getElementById('album_base').offsetWidth-80;
  maxGalleryXPos=imageGalleryObj.offsetLeft; 
  minGalleryXPos=imageGalleryWidth-document.getElementById('album_fim').offsetLeft;

  var slideshowImages=imageGalleryObj.getElementsByTagName('IMG');
  for (var no=0; no<slideshowImages.length; no++)
  {
    slideshowImages[no].onmouseover=showImage;
  }
  
  gallerySlide();
}

window.onload=initSlideShow;