// JavaScript Document
var timerlen = 5;		/*how often the Javascript function will run to alter the DIV’s properties (altering height or opacity)… it’s probably best to leave this at 5. Any lower will be slightly smoother, but will require your visitors have a better computer (otherwise it’ll be choppy), and much higher will be choppy on everyone, because it’s not updating enough to look smooth.*/
var slideAniLen = 250;	/*how long it should take a DIV to completely slide up or completely slide down. This is in milliseconds, so setting it to 500 means it’ll take half a second to complete the animation effect. This is fairly quick, so some people might want to increase and make it a bit slower.*/

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 slidedown(objname){
        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);
}

function slideup(objname){
        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);
}


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

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

obj[objname].style.display = "block";
startTime[objname] = (new Date()).getTime();
endHeight[objname] = obj[objname].scrollHeight + 40;

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

/*function startslide(objname){	/*originele functie waarbij de height gespecificeerd moet worden in de inline css*/
/*obj[objname] = document.getElementById(objname);
obj[objname].style.display = "block";
endHeight[objname] = parseInt(obj[objname].offsetHeight);
obj[objname].style.display = "none";
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];

        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);
  }
}