var galleryImageView;
var galleryCaptionBox;
var galleryPhotoIndex = 0;
var gallerySlideRate = 5000;
var galleryPhotoImage;
var galleryBtnNext;
var galleryBtnPrev;
var gallerySlideshowSwitch;
var gallerySlideshowOn = false;
var galleryPhotoArray = new Array();
var galleryCaptionArray = new Array();
var galleryImageLinksArray = new Array();
var galleryTimout;



function galleryPhotoNext(){
  if(galleryPhotoIndex < (galleryPhotoArray.length - 1)){
    galleryPhotoIndex++;
    toggleGalleryImage(); 
  }
  return false;
}

function galleryPhotoPrevious(){  
  if(galleryPhotoIndex > 0){
    galleryPhotoIndex--;
    toggleGalleryImage();
  }
  return false;
}


function LoadGallery(){	    
	galleryImageView = document.getElementById("galleryImage");
	galleryCaptionBox = document.getElementById("galleryCaption");
	galleryBtnNext = document.getElementById("galleryBtnNext");
	galleryBtnPrev = document.getElementById("galleryBtnPrev");
	gallerySlideshowSwitch = document.getElementById("gallerySlideshowSwitch");	
		
	if(galleryImageView != null){	 
		galleryImageView.innerHTML = "";
		galleryPhotoImage = document.createElement("img");  
		galleryPhotoImage.src = galleryPhotoArray[galleryPhotoIndex];
		galleryPhotoImage.alt = "";
		galleryPhotoImage.id = "galleryImage";

		galleryImageView.appendChild(galleryPhotoImage);
		toggleGalleryImage();
	}	
	
  
	if(gallerySlideshowSwitch != null){	  
		gallerySlideshowSwitch.onclick = toggleGallerySlideshow ;
		gallerySlideshowSwitch.style.cursor = "pointer";
		gallerySlideshowSwitch.innerHTML = "View Slideshow";
	}
	
}

function toggleGalleryImage(){ 
	if(galleryPhotoArray.length > 0){	
		galleryPhotoImage.src = galleryPhotoArray[galleryPhotoIndex];
		toggleGalleryCaption();
		toggleCountDisplay();
		toggleControls();
	}
	
	if(gallerySlideshowOn){
		if(galleryPhotoIndex == (galleryPhotoArray.length -1)){
			galleryPhotoIndex = -1;
		}
		galleryTimout = setTimeout("galleryPhotoNext()", gallerySlideRate);
	}
	
	return;
}

function toggleControls(){
	if(galleryBtnNext != null && galleryBtnPrev != null){	
		if(gallerySlideshowOn){	
			galleryBtnNext.style.display = "none"
			galleryBtnPrev.style.display = "none";			
		}else{
			galleryBtnNext.style.display = "inline";
			galleryBtnPrev.style.display = "inline";
			
			if(galleryPhotoIndex == 0){
				galleryBtnNext.src = "http://www.labour.org.nz/images/photobox_next_on.gif";
				galleryBtnPrev.src = "http://www.labour.org.nz/images/photobox_previous_off.gif";
			}
			else if(galleryPhotoIndex == (galleryPhotoArray.length -1)){
				galleryBtnNext.src = "http://www.labour.org.nz/images/photobox_next_off.gif";
				galleryBtnPrev.src = "http://www.labour.org.nz/images/photobox_previous_on.gif";
			}else{
				galleryBtnNext.src = "http://www.labour.org.nz/images/photobox_next_on.gif";
				galleryBtnPrev.src = "http://www.labour.org.nz/images/photobox_previous_on.gif";
			}		
		}
	}
	return;
}


function toggleCountDisplay(){
    var galleryPhotoCountDisplay = document.getElementById("galleryPhotoCount");
	if(galleryPhotoCountDisplay != null){
		galleryPhotoCountDisplay.innerHTML = "Photo " + (galleryPhotoIndex + 1) + " of " + galleryPhotoArray.length;
	}
	return;
}

function toggleGalleryCaption(){
	if(galleryCaptionBox && galleryCaptionArray[galleryPhotoIndex]){
		galleryCaptionBox.innerHTML = galleryCaptionArray[galleryPhotoIndex];
	}else{
		galleryCaptionBox.innerHTML = "";
	}
	return;
}

function toggleGallerySlideshow(){
  if(gallerySlideshowOn){
    clearTimeout(galleryTimout);
    gallerySlideshowOn = false;
    gallerySlideshowSwitch.innerHTML = "View Slideshow";
  }else{
    gallerySlideshowOn = true;
    gallerySlideshowSwitch.innerHTML = "Turn off slideshow";
  }  
  toggleGalleryImage();
}