var DDSPEED = 10;
var DDTIMER = 15;
var OFFSET = -2;
var ZINT = 100;

function ddMenu(id, d) {
  var h = document.getElementById(id + '-ddheader');
  var c = document.getElementById(id + '-ddcontent');
  clearInterval(c.timer);
  if (d == 1) {
    clearTimeout(h.timer);
    c.style.display = 'block';
    if (c.maxh && c.maxh <= c.offsetHeight) { return }
    else if (!c.maxh) {
      c.style.left = (h.offsetWidth + OFFSET) + 'px';
      c.style.height = 'auto';
      c.maxh = c.offsetHeight;
      c.style.height = '0px';
    }
    ZINT = ZINT + 1;
    c.style.zIndex = ZINT;
    c.timer = setInterval(function () { ddSlide(c, 1) }, DDTIMER);
  } else {
    h.timer = setTimeout(function () { ddCollapse(c) }, 50);
  }
}

function ddCollapse(c) {
  c.timer = setInterval(function () { ddSlide(c, -1) }, DDTIMER);
}

function cancelHide(id) {
  var h = document.getElementById(id + '-ddheader');
  var c = document.getElementById(id + '-ddcontent');
  clearTimeout(h.timer);
  clearInterval(c.timer);
  if (c.offsetHeight < c.maxh) {
    c.timer = setInterval(function () { ddSlide(c, 1) }, DDTIMER);
  }
}

function ddSlide(c, d) {
  var currh = c.offsetHeight;
  var dist;
  if (d == 1) {
    dist = Math.round((c.maxh - currh) / DDSPEED);
  } else {
    dist = Math.round(currh / DDSPEED);
  }
  if (dist <= 1 && d == 1) {
    dist = 1;
  }
  c.style.height = currh + (dist * d) + 'px';
  c.style.opacity = currh / c.maxh;
  c.style.filter = 'alpha(opacity=' + (currh * 100 / c.maxh) + ')';
  if (currh > (c.maxh - 2) && d == 1) {
    clearInterval(c.timer);
  } else if (dist < 1 && d != 1) {
    clearInterval(c.timer);
    c.style.display = 'none';
  }
}