var _iHero = 1;
  var _iHeroTimer = null;
  var _iSponsor = 1;
  var _iSponsorTimer = null;

  function clearHeroTimer()
  {
    if (_iHeroTimer != null)
    {
      window.clearTimeout(_iHeroTimer);
      _iHeroTimer = null;
    }
  }

  function clearSponsorTimer()
  {
    if (_iSponsorTimer != null)
    {
      window.clearTimeout(_iSponsorTimer);
      _iSponsorTimer = null;
    }
  }

  function resetHeroTimer()
  {
    clearHeroTimer();
    _iHeroTimer = window.setTimeout(swapHeroImage, 6000);
  }

  function resetSponsorTimer()
  {
    clearSponsorTimer();

    // reset timer
    _iSponsorTimer = window.setTimeout(swapSponsorImage, 2500);
  }

  function forceHeroImage(i)
  {
    clearHeroTimer();

    _iHero = i;
    swapHeroImage();
  }

  function forceSponsorImage(i)
  {
    clearSponsorTimer();

    _iSponsor = i;
    swapSponsorImage();
  }

  function swapHeroImage()
  {
    var id = _iHero;
    var sHero = id.toString();
    if (id < 10)
    {
      sHero = "0" + sHero;
    }
    document.getElementById("iHeroImage").src = "/images/techconf/hero/hero" + sHero + ".jpg";

    _iHero++;
    if (_iHero > 6)
    {
      _iHero = 1;
    }

    resetHeroTimer();
  }

  function swapSponsorImage()
  {
    var id = _iSponsor;
    var sSponsor = id.toString();
    if (id < 10)
    {
      sSponsor = "0" + sSponsor;
    }
    document.getElementById("iSponsorImage").src = "/images/techconf/sponsor/sponsor" + sSponsor + ".gif";

    _iSponsor++;
    if (_iSponsor > 10)
    {
      _iSponsor = 1;
    }

    resetSponsorTimer();
  }

  function expandWed() {
    document.getElementById("divViewWed").style.display = "none";
    document.getElementById("divHideWed").style.display = "";

    showSession("divPCC1", "divPCC1h4", "divPCC1h4Link");
    showSession("divPDSL1", "divPDSL1h4", "divPDSL1h4Link");
    showSession("divUE1", "divUE1h4", "divUE1h4Link");
    showSession("divIS1", "divIS1h4", "divIS1h4Link");
    showSession("divL1", "divL1h4", "divL1h4Link");
    showSession("divCIO1", "divCIO1h4", "divCIO1h4Link");
  }

  function hideWed() {
    document.getElementById("divViewWed").style.display = "";
    document.getElementById("divHideWed").style.display = "none";

    hideSession("divPCC1", "divPCC1h4", "divPCC1h4Link");
    hideSession("divPDSL1", "divPDSL1h4", "divPDSL1h4Link");
    hideSession("divUE1", "divUE1h4", "divUE1h4Link");
    hideSession("divIS1", "divIS1h4", "divIS1h4Link");
    hideSession("divL1", "divL1h4", "divL1h4Link");
    hideSession("divCIO1", "divCIO1h4", "divCIO1h4Link");
  }

  function expandThur() {
    document.getElementById("divViewThur").style.display = "none";
    document.getElementById("divHideThur").style.display = "";

    showSession("divPCC2", "divPCC2h4", "divPCC2h4Link");
    showSession("divPDSL2", "divPDSL2h4", "divPDSL2h4Link");
    showSession("divUE2", "divUE2h4", "divUE2h4Link");
    showSession("divIS2", "divIS2h4", "divIS2h4Link");
    showSession("divL2", "divL2h4", "divL2h4Link");
    showSession("divCIO2", "divCIO2h4", "divCIO2h4Link");
  }

  function hideThur() {
    document.getElementById("divViewThur").style.display = "";
    document.getElementById("divHideThur").style.display = "none";

    hideSession("divPCC2", "divPCC2h4", "divPCC2h4Link");
    hideSession("divPDSL2", "divPDSL2h4", "divPDSL2h4Link");
    hideSession("divUE2", "divUE2h4", "divUE2h4Link");
    hideSession("divIS2", "divIS2h4", "divIS2h4Link");
    hideSession("divL2", "divL2h4", "divL2h4Link");
    hideSession("divCIO2", "divCIO2h4", "divCIO2h4Link");
  }

  function hideSession(id, h4, h4Link) {
    document.getElementById(id).style.display = "none";
    document.getElementById(h4).style.display = "none";
    document.getElementById(h4Link).style.display = "";
  }

  function showSession(id, h4, h4Link) {
    document.getElementById(id).style.display = "";
    document.getElementById(h4).style.display = "";
    document.getElementById(h4Link).style.display = "none";
  }