var timerlen = 25;
var slideAniLen = 1000000;
var moveout = 1;

var timerID = new Array();
var startTime = new Array();
var obj = new Array();
var endHeight = new Array();
var moving = new Array();
var dir = new Array();

function decide(objname,nextorprev,pages){
	var pages2 = parseInt(pages);
	var i = 0;
	while(i<pages2){
		objname2 = objname+i;
		objname3 = "m2div"+i;
		if (document.getElementById(objname2).style.display != "none") {

			if(nextorprev == "prev") {
				if(i>0) {
					
					slideup2(objname2,i);
					slidedown2(objname+(i-1),objname+(i+1),i);
					
					
				}
					
			} else {
				if(i<(pages2-1)) {
					
					slidedown(objname+(i+1),i,pages2);
					slideup(objname2,i,pages2);
					
				}
					
			}
	
			return;
			
		} else {
			i=i+1;
		}
	}
}
function pageshow2(objname3){
	obj[objname3] = document.getElementById(objname3);
	obj[objname3].style.display = "block";
}
function pagehide2(objname3){
	obj[objname3] = document.getElementById(objname3);
	obj[objname3].style.display = "none";
}

function slidedown(objname,i,pages2){
        if(moving[objname])
                return;

        if(document.getElementById(objname).style.display != "none")
                return; // cannot slide down something that is already visible

        moving[objname] = true;
        dir[objname] = "down";
        startslide(objname);
        next(i,pages2);
}

function slidedown2(objname,objname2,i){
        if(moving[objname])
                return;
                
        if(document.getElementById(objname).style.display != "none")
                return; // cannot slide down something that is already visible
        try {
        if(document.getElementById(objname2).style.display != "none")
                return; // cannot slide up something that is already hidden
                }catch(err)
  {

  }
                
        moving[objname] = true;
        dir[objname] = "down";
        startslide(objname);
        next2(i);
}

function slideup(objname,i,pages2){
        if(moving[objname])
                return;
                

        if(document.getElementById(objname).style.display == "none")
                return; // cannot slide up something that is already hidden

        moving[objname] = true;
        dir[objname] = "up";
        startslide(objname);
        next(i,pages2);
}

function slideup2(objname,i){
        if(moving[objname])
                return;
                

        if(document.getElementById(objname).style.display == "none")
                return; // cannot slide up something that is already hidden

        moving[objname] = true;
        dir[objname] = "up";
        startslide(objname);
        next2(i);
}

function next(i,pages2){
pageshow2("m2div"+(i+1));
					pagehide2("m2div"+(i));
					document.getElementById("terug").style.backgroundImage="url(http://www.eenidealebaan.nl/images/b/verderterugb_01.png)"
					document.getElementById("terug2").style.backgroundImage="url(http://www.eenidealebaan.nl/images/b/verderterugb_01.png)"
					document.getElementById("verder").style.backgroundImage="url(http://www.eenidealebaan.nl/images/b/verderterugb_02.png)"
					document.getElementById("verder2").style.backgroundImage="url(http://www.eenidealebaan.nl/images/b/verderterugb_02.png)"
					document.getElementById("verder").style.cursor="pointer"
					document.getElementById("verder2").style.cursor="pointer"
					document.getElementById("terug").style.cursor="pointer"
					document.getElementById("terug2").style.cursor="pointer"
					
					
					if (i==(pages2-2)) {
						document.getElementById("verder").style.backgroundImage="url(http://www.eenidealebaan.nl/images/b/verderterug_02c.png)"
						document.getElementById("verder2").style.backgroundImage="url(http://www.eenidealebaan.nl/images/b/verderterug_02c.png)"
						document.getElementById("verder").style.cursor="default"
						document.getElementById("verder2").style.cursor="default"
					}
}
function next2(i){
pageshow2("m2div"+(i-1));
					pagehide2("m2div"+(i));
					document.getElementById("terug").style.backgroundImage="url(http://www.eenidealebaan.nl/images/b/verderterugb_01.png)"
					document.getElementById("terug2").style.backgroundImage="url(http://www.eenidealebaan.nl/images/b/verderterugb_01.png)"
					document.getElementById("verder").style.backgroundImage="url(http://www.eenidealebaan.nl/images/b/verderterugb_02.png)"
					document.getElementById("verder2").style.backgroundImage="url(http://www.eenidealebaan.nl/images/b/verderterugb_02.png)"
					document.getElementById("verder").style.cursor="pointer"
					document.getElementById("verder2").style.cursor="pointer"
					document.getElementById("terug").style.cursor="pointer"
					document.getElementById("terug2").style.cursor="pointer"
					
					
					if (i==1) {
						document.getElementById("terug").style.backgroundImage="url(http://www.eenidealebaan.nl/images/b/verderterug_01c.png)"
						document.getElementById("terug2").style.backgroundImage="url(http://www.eenidealebaan.nl/images/b/verderterug_01c.png)"
						document.getElementById("terug").style.cursor="default"
						document.getElementById("terug2").style.cursor="default"
					}
}

function startslide(objname){
        obj[objname] = document.getElementById(objname);

        endHeight[objname] = parseInt(obj[objname].style.height);
        startTime[objname] = (new Date()).getTime();


        if(dir[objname] == "down"){
                obj[objname].style.height = "1px";
        }

        obj[objname].style.display = "block";

        timerID[objname] = setInterval('slidetick(\'' + objname + '\');',timerlen);
}

function slidetick(objname){
        var elapsed = ((new Date()).getTime() - startTime[objname]);
        var elapsed = elapsed * elapsed * moveout;
        if (elapsed > slideAniLen)
                endSlide(objname)
        else {
                var d = Math.round((elapsed / slideAniLen) * endHeight[objname]);
                if(dir[objname] == "up") 
                        d = endHeight[objname] - d;

                obj[objname].style.height = d + "px";
        }

        return;
}

function endSlide(objname){
        clearInterval(timerID[objname]);

        if(dir[objname] == "up")
                obj[objname].style.display = "none";

        obj[objname].style.height = endHeight[objname] + "px";

        delete(moving[objname]);
        delete(timerID[objname]);
        delete(startTime[objname]);
        delete(endHeight[objname]);
        delete(obj[objname]);
        delete(dir[objname]);

        return;
}
function toggleSlide(objname){
  if(document.getElementById(objname).style.display == "none"){
    // div is hidden, so let's slide down
    slidedown(objname);
  }else{
    // div is not hidden, so slide up
    slideup(objname);
  }
}