var currentSlide = 1;
var nextSlide
var prevSlide = 1;
var totalSlides = 0
var slideArray
var zindexPos = 1
var slideActive = false;
var lbTimer
var timerDelay = 9000;
function letterboxInit(){
 
    // If there is a letterbox on the page, then page watching the links
    if ($('letterbox')){
        if($('lbBack'))$('lbBack').onclick = function(){if (slideActive == false){moveSlide('back');}return(false);}
        if($('lbNext'))$('lbNext').onclick = function(){if (slideActive == false){moveSlide('next');}return(false);}
        
        // Get the total number of slides
        slideArray = $('letterbox').getElementsByTagName("div");
        
        for (var i=0; i < slideArray.length; i++) {
            //$(slideArray[i]).removeClassName("hidden") // Gets rid of the Hidden class which is added for the none JS version
            totalSlides++;
        }
    }
    if (slideArray.length>1){
        // Start the timer to auto run the slideshow
        lbTimer = setTimeout('moveSlide("next")',timerDelay);
    }
}

function moveSlide(dir){

    clearTimeout (lbTimer);
    
    //if (slideActive == false){ // used to block the function whilst it is running
        slideActive = true;
        if (dir == "back"){
            if(parseInt(currentSlide-1) <= 0){
				numberToAdd = parseInt(totalSlides-1)
				nextSlide = parseInt(currentSlide+numberToAdd)
            }else{
				nextSlide = parseInt(currentSlide-1)
            }
        }else{
            if(parseInt(currentSlide+1) > parseInt(totalSlides)){
				numberToRemove = parseInt(currentSlide-1)
				nextSlide = parseInt(currentSlide-numberToRemove)
            }else{
				nextSlide = parseInt(currentSlide+1)
            }
        }
        $('lb'+nextSlide).hide();
        $('lb'+nextSlide).removeClassName("hidden")
        
        new Effect.Appear('lb'+nextSlide, {duration: 0.5,queue:'end'});
        new Effect.Fade('lb'+currentSlide, {duration: 0.5,queue:'end',afterFinish:function(){
            lbTimer = setTimeout('moveSlide("'+dir+'")',timerDelay);
            slideActive = false;
        }});
        currentSlide = nextSlide;
   // }
}

document.observe("dom:loaded",function() {letterboxInit();});