var DragRegObserver = Class.create();
DragRegObserver.prototype = {
  initialize: function(element) {
    this.element = $(element);
  },
  onStart: function() {},
  onEnd: function (eventName, draggable, event) {
    if (Draggables.activeDraggable.element == this.element) {
      elem = draggable.element;
      new Ajax.Request('http://localhost:3301/savepos/' + elem.id +
                       '/' + elem.style.top + '/' + elem.style.left);
    }
  }
}

function maxZIndex() {
  return $$('.draggable').map(function(d) { return d.getStyle("z-index") }).max();
}