// COSI Home Rotator v1.0 by
//   Kevin Pfefferle, Web Manager
//   www.cosi.org
// All Rights Reserved.

// Adapted from:
//
// CSS Linked Photo Shuffler v1.1 by
//   Carl Camera
//   http://iamacamera.org 
//
// SetOpacity Function and inpiration from Photo Fade by
//   Richard Rutter
//   http://clagnut.com
//
// License: Creative Commons Attribution 2.5  License
//   http://creativecommons.org/licenses/by/2.5/
//
// Customize your photo shuffle settings
// 
// * Surround the target <img /> with an anchor <a> and <div>. 
//   specify unique id= in all three
// * The first and final photo displayed is in the html <img> tag
// * The image array contains paths to photos you want in the rotation. 
//   If you want the first photo in the rotation, then it's best to
//   put it as the final array image.  All photos must be same dimension
// * The Href array contains the link you want associated with each image
//   each image must have a corresponding link.

var gblPhotoShufflerDivId = "homeRotator";
var gblPhotoShufflerImgId = "homeRotatorImg";
var gblPhotoShufflerAnchorId = "homeRotatorLink";

// SET BY "homeRotatorArrays.php"...
//var gblImg = new Array(
//  "/files/file/home_features/Home.MoonFilm.jpg",
//  "/files/file/home_features/Home.Alps.jpg",
//  "/files/file/home_features/Home.SSTB.jpg"
//  );
//var gblHref = new Array(
//  "/visitors/theater/moonfilm/",
//  "/visitors/theater/alps/",
//  "/visitors/exhibits/sesame-street/"
//  );

var gblPauseSeconds = 6;
var gblFadeSeconds = .75;

// End Customization section

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

window.onload = function() {
  document.getElementById("rotateR").onclick = photoShufflerFwd;
  document.getElementById("rotateL").onclick = photoShufflerBack;
  photoShufflerLaunch();
}

function photoShufflerLaunch()
{
  document.getElementById(gblPhotoShufflerDivId).style.backgroundImage='url(' + gblImg[gblOnDeck] + ')';
  gblTime = 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;
    photoShufflerShuffle();
    // pause before next fade
    gblTime = setTimeout("photoShufflerFade()",gblPauseSeconds*1000);
  }
  else
  {
    gblOpacity -= fadeDelta;
    // setOpacity(theimg,gblOpacity);
    $(theimg).css('opacity',gblOpacity/100)
    gblTime = setTimeout("photoShufflerFade()",30);  // 1/30th of a second
  }
}

function photoShufflerShuffle()
{
  var thediv = document.getElementById(gblPhotoShufflerDivId);
  var theimg = document.getElementById(gblPhotoShufflerImgId);
  var theanchor = document.getElementById(gblPhotoShufflerAnchorId);
	
  // copy div background-image to img.src
  theimg.src = gblImg[gblOnDeck];
  theanchor.href = gblHref[gblOnDeck];
  window.status = gblHref[gblOnDeck]; // updates status bar (optional)
  // set img opacity to 100
  // setOpacity(theimg,100);
  $(theimg).css('opacity',1)

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

  // slide next image underneath
  thediv.style.backgroundImage='url(' + gblImg[gblOnDeck] + ')';
}

// 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;
// }

// Addons for indexing buttons:
function photoShufflerFwd() {
  clearTimeout(gblTime);
  gblOpacity = 100;
  photoShufflerShuffle();
  // pause before next fade
  gblTime = setTimeout("photoShufflerFade()",gblPauseSeconds*1000);
}

function photoShufflerBack() {
  clearTimeout(gblTime);
  gblOpacity = 100;
  gblOnDeck = gblOnDeck - 2;
  if (gblOnDeck < 0) {
    gblOnDeck = gblOnDeck + gblDeckSize;
  }
  photoShufflerShuffle();
  // pause before next fade
  gblTime = setTimeout("photoShufflerFade()",gblPauseSeconds*1000);
}