var sliderIntervalId = 0;
var sliderHeight = 0;
var sliding = false;
var slideSpeed = 20;
var sliderHeightsList = Array();
var sliderCurrentHeightsList = Array();

/**
 * We collect all the content heights corresponding to the elements.
 */
function set_height_per_element(this_element_id) {
  slider = document.getElementById(this_element_id);
  sliderHeightsList[this_element_id] = slider.offsetHeight;
  sliderCurrentHeightsList[this_element_id] = 0;
  slider.style.height = '0px';
}

/**
 * Slide action.
 * Use the content length for this element. 
 */
function Slide(this_element_id) {
  if (sliding) return;

  sliding = true;
  sliderHeight = sliderCurrentHeightsList[this_element_id];
  if (sliderHeight == null) return;
  sliderMaxHeight = sliderHeightsList[this_element_id];
  if(sliderHeight == sliderMaxHeight)
    sliderIntervalId = setInterval('SlideUpRun(\''+this_element_id+'\')', 30);
  else
    sliderIntervalId = setInterval('SlideDownRun(\''+this_element_id+'\')', 30);
}

function SlideUpRun(this_element_id) {
   slider = document.getElementById(this_element_id);
   if(sliderHeight <= 0) {
      sliding = false;
      sliderHeight = 0;
      slider.style.height = '0px';
      sliderCurrentHeightsList[this_element_id] = sliderHeight;
      clearInterval(sliderIntervalId);
   }
   else {
      sliderHeight -= slideSpeed;
      if(sliderHeight < 0)
         sliderHeight = 0;
      slider.style.height = sliderHeight + 'px';
   }
}

function SlideDownRun(this_element_id) {
   slider = document.getElementById(this_element_id);
   sliderMaxHeight = sliderHeightsList[this_element_id];
   if(sliderHeight >= sliderMaxHeight) {
      sliding = false;
      sliderHeight = sliderMaxHeight;
      slider.style.height = sliderMaxHeight+'px';
      sliderCurrentHeightsList[this_element_id] = sliderHeight;
      clearInterval(sliderIntervalId);
   }
   else {
      sliderHeight += slideSpeed;
      if(sliderHeight > sliderMaxHeight)
         sliderHeight = sliderMaxHeight;
      slider.style.height = sliderHeight + 'px';
   }
}







/*
function sliding(element_id) {
  element_object = document.getElementById(element_id);
  if (element_object.style.display == "none") {
    element_object.style.display = "block";
  } else {
    element_object.style.display = "none";
  }
}




function slideExample1(elementId, headerElement)
{
   var element = document.getElementById(elementId);
   if(element.up == null || element.down)
   {
      animate(elementId, 0, 20, 150, 0, 250, null);
      element.up = true;
      element.down = false;
      headerElement.innerHTML = 'vvv';
   }
   else
   {
      animate(elementId, 0, 20, 150, 130, 250, null);
      element.down = true;
      element.up = false;
      headerElement.innerHTML = '^^^';
   }
}

function animate() {

}
*/