var gblPhotoShufflerDivId = "irdiv1";
var gblPhotoShufflerImgId = "irimg1";

var gblImg = new Array("system/html/2.gif", "system/html/3.gif", "system/html/4.gif", "system/html/5.gif", "system/html/6.gif", "system/html/7.gif",  "system/html/8.gif", "system/html/9.gif", "system/html/10.gif", "system/html/11.gif", "system/html/12.gif", "system/html/13.gif", "system/html/14.gif", "system/html/15.gif", "system/html/16.gif", "system/html/17.gif", "system/html/18.gif","system/html/19.gif", "system/html/20.gif", "system/html/21.gif", "system/html/22.gif", "system/html/23.gif");


var gblPauseSeconds = 3;
var gblFadeSeconds = 1;
var gblRotations = 999;

// End Customization section

var gblDeckSize = gblImg.length;
var gblOpacity = 100;
var gblOnDeck = 0;

var gblStartImg;
var gblImageRotations = gblDeckSize * (gblRotations+1);

//-- Random
var gblOnDeckRandom = 0;

/* functions */
window.onload = photoShufflerLaunch;

function photoShufflerLaunch()
{
	var theimg = document.getElementById(gblPhotoShufflerImgId);
    gblStartImg = theimg.src; // save away to show as final image


document.getElementById(gblPhotoShufflerDivId).style.backgroundImage='url(' + gblImg[gblOnDeck] + ')';

setTimeout("photoShufflerFade()",gblPauseSeconds*1000);
}

function photoShufflerFade()
{
	var theimg = document.getElementById(gblPhotoShufflerImgId);

	// determine delta based on number of fade seconds
// the slower the fade the more increments needed
    var fadeDelta = 100 / (30 * gblFadeSeconds);

// fade top out to reveal bottom image
if (gblOpacity < 2*fadeDelta ) 
{
  gblOpacity = 100;
  // stop the rotation if we're done
  if (gblImageRotations < 1) return;
  photoShufflerShuffle();
  // pause before next fade
      setTimeout("photoShufflerFade()",gblPauseSeconds*1000);
}
else
{
  gblOpacity -= fadeDelta;
  setOpacity(theimg,gblOpacity);
  setTimeout("photoShufflerFade()",30);  // 1/30th of a second
}
}

function photoShufflerShuffle()
{
var thediv = document.getElementById(gblPhotoShufflerDivId);
var theimg = document.getElementById(gblPhotoShufflerImgId);



// copy div background-image to img.src
theimg.src = gblImg[gblOnDeck];

theimg.src = gblImg[gblOnDeckRandom];

	

// set img opacity to 100
setOpacity(theimg,100);

// shuffle the deck
gblOnDeck = ++gblOnDeck % gblDeckSize;

	
// rotated through decksize then create new array
var asLucky = new Array ( 0, 1, 2, 3, 4, 5 ,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22);
fisherYates(asLucky);

// check if number was used before
if (gblOnDeckRandom == asLucky[0])
{
	gblOnDeckRandom = asLucky[1];
	
} else {
	
	gblOnDeckRandom = asLucky[0];
}


// decrement rotation counter
if (--gblImageRotations < 1)
{
  // insert start/final image if we're done
  gblImg[gblOnDeck] = gblStartImg;

  }

// slide next image underneath

thediv.style.backgroundImage='url(' + gblImg[gblOnDeck] + ')';

thediv.style.backgroundImage='url(' + gblImg[gblOnDeckRandom] + ')';
}

function setOpacity(obj, opacity) {
  opacity = (opacity == 100)?99.999:opacity;
  
  // IE/Win
  obj.style.filter = "alpha(opacity:"+opacity+")";
  
  // Safari<1.2, Konqueror
  obj.style.KHTMLOpacity = opacity/100;

  // Older Mozilla and Firefox
  obj.style.MozOpacity = opacity/100;

  // Safari 1.2, newer Firefox and Mozilla, CSS3
  obj.style.opacity = opacity/100;
}

function fisherYates ( myArray ) {
  var i = myArray.length;
  if ( i == 0 ) return false;
  while ( --i ) {
     var j = Math.floor( Math.random() * ( i + 1 ) );
     var tempi = myArray[i];
     var tempj = myArray[j];
     myArray[i] = tempj;
     myArray[j] = tempi;
   }
}