var sliderIntervalIdUp = 0;
var sliderIntervalIdDown = 0;
var slidingArray = new Array(false, false, false, false, false);
var sliderHeight = new Array(250, 0, 0, 0, 0, 0);
var maxHeight = new Array(250, 180, 200, 690, 180, 120);
var slideSpeed = 8;


/* metody */

elem = function(name) {
  return document.getElementById(name);
}

showStep = function(idStep) {
  if (idStep == 1) {
    Slide("divGlowna", "down", 0);
    if (sliderHeight[1] > 0)
      Slide("divOferta", "up", 1);
    if (sliderHeight[2] > 0)
      Slide("divTechnologie", "up", 2);
    if (sliderHeight[3] > 0)
      Slide("divRealizacje", "up", 3);
    if (sliderHeight[4] > 0)
      Slide("divKontakt", "up", 4)
  }
  if (idStep == 2) {
    if (sliderHeight[0] > 0)
      Slide("divGlowna", "up", 0);
    Slide("divOferta", "down", 1);
    if (sliderHeight[2] > 0)
      Slide("divTechnologie", "up", 2);
    if (sliderHeight[3] > 0)
      Slide("divRealizacje", "up", 3);
    if (sliderHeight[4] > 0)
      Slide("divKontakt", "up", 4);
  }
  if (idStep == 3) {
    if (sliderHeight[0] > 0)
      Slide("divGlowna", "up", 0);
    if (sliderHeight[1] > 0)
      Slide("divOferta", "up", 1);
    Slide("divTechnologie", "down", 2);
    if (sliderHeight[3] > 0)
      Slide("divRealizacje", "up", 3);
    if (sliderHeight[4] > 0)
      Slide("divKontakt", "up", 4);
  }
  if (idStep == 4) {
    if (sliderHeight[0] > 0)
      Slide("divGlowna", "up", 0);
    if (sliderHeight[1] > 0)
      Slide("divOferta", "up", 1);
    if (sliderHeight[2] > 0)
      Slide("divTechnologie", "up", 2);
    Slide("divRealizacje", "down", 3);
    if (sliderHeight[4] > 0)
      Slide("divKontakt", "up", 4);
  }
  if (idStep == 5) {
    if (sliderHeight[0] > 0)
      Slide("divGlowna", "up", 0);
    if (sliderHeight[1] > 0)
      Slide("divOferta", "up", 1);
    if (sliderHeight[2] > 0)
      Slide("divTechnologie", "up", 2);
    if (sliderHeight[3] > 0)
      Slide("divRealizacje", "up", 3);
    Slide("divKontakt", "down", 4);
  }
}


Slide = function(element, direction, index) {
  if (slidingArray[index])
    return;
  slidingArray[index] = true;
  if (direction == "up")
    sliderIntervalIdUp = setInterval("SlideUpRun('" + element + "', " + index + ")", 5);
  else
    sliderIntervalIdDown = setInterval("SlideDownRun('" + element + "', " + index + ")", 5);
}

SlideUpRun = function(element, index) {
  slider = elem(element);
  if (sliderHeight[index] <= 0) {
    slidingArray[index] = false;
    sliderHeight[index] = 0;
    slider.style.height = "0px";
    clearInterval(sliderIntervalIdUp);
  } else {
    sliderHeight[index] -= slideSpeed;
    if (sliderHeight[index] < 0)
      sliderHeight[index] = 0;
    slider.style.height = sliderHeight[index] + "px";
  }
}

SlideDownRun = function(element, index) {
  slider = elem(element);
  if (sliderHeight[index] >= maxHeight[index]) {
    slidingArray[index] = false;
    sliderHeight[index] = maxHeight[index];
    slider.style.height = sliderHeight[index] + "px";
    clearInterval(sliderIntervalIdDown);
  } else {
    sliderHeight[index] += slideSpeed;
    if (sliderHeight[index] > maxHeight[index])
      sliderHeight[index] = maxHeight[index];
    slider.style.height = sliderHeight[index] + "px";
  }
}

checkArray = function(array, item) {
  for (i = 0; i < array.length; i++) {
    if (array[i] == item)
      return true;
  }
  return false;
}