var folios = new Array();
var currentFolioIndex = -1;
var currentFolioName = '';
var opacities = new Array();

var folioUpdating = false;
var folioRefresh = 80;

function SetCurrentFolio(folioIndex, folioName)
{
  currentFolioIndex = folioIndex;
  currentFolioName = folioName;
  
  if (folioIndex != -1)
  {
    SetFolioOpacity(folioIndex, opacities[folioIndex] + 0.15);
  }

  if (!folioUpdating)
  {
    folioUpdating = true;
    Update();
  }
}

function Start()
{
  setTimeout('Update();', folioRefresh);
}

function Update()
{
  var keepUpdating = false;
  var currentPageUrl = document.getElementsByName("MainFrame")[0].src;

  for (i = 0; i < folios.length; i++)
  {
    var currentOpacity = opacities[i];
    if (folios[i] == currentFolioName)
    {
      if (currentOpacity < 1)
      {
        SetFolioOpacity(i, currentOpacity + 0.15)
        keepUpdating = true;
      }
    }
    else
    {
      if (currentOpacity > 0.21)
      {
        currentOpacity = currentOpacity - 0.08;
        if (currentOpacity < 0.21)
        {
          currentOpacity = 0.21;
        }
        SetFolioOpacity(i, currentOpacity);
        keepUpdating = true;
      }
      else if (currentOpacity < 0.2)
      {
        SetFolioOpacity(i, currentOpacity + 0.02)
        keepUpdating = true;
      }
    }

    var folioUrl = '/' + folios[i] + '.htm';
    var folioDiv = document.getElementById("folioDiv" + folios[i]);
    if (currentPageUrl.length > folioUrl.length
        && currentPageUrl.substring(currentPageUrl.length - folioUrl.length) == folioUrl)
    {
      folioDiv.className = "folio-active";
    }
    else
    {
      folioDiv.className = "folio";
    }
  }

  if (keepUpdating)
  {
    setTimeout('Update();', folioRefresh);
  }
  else
  {
    folioUpdating = false;
  }
}

function SetFolioOpacity(i, opacity)
{
  var folioImage = document.getElementsByName("folioImage" + folios[i])[0];

  if (opacity >= 1)
  {
    folioImage.style.opacity = 1;
    folioImage.style.display = 'block';
    folioImage.style.filter = '';
  }
  else if (opacity > 0)
  {
    folioImage.style.opacity = opacity;
    folioImage.style.display = 'block';
    folioImage.style.filter = 'alpha(opacity=' + (opacity * 100) + ')';
  }
  else
  {
    folioImage.style.opacity = 0;
    folioImage.style.display = 'none';
    folioImage.style.filter = 'alpha(opacity=0)';
  }

  opacities[i] = opacity;
}

function PickFolio()
{
  var folioPick = null;
  
  if (location.search != null && location.search.length > 2)
  {
    var fields = location.search.substring(1).split('/');
    for (i = 0; i < folios.length; i++)
    {
      if (folios[i].toLowerCase() == fields[0].toLowerCase())
      {
        folioPick = folios[i];
        break;
      }
    }
  }
  
  if (folioPick == null)
  {
    var pick = Math.floor(Math.random() * folios.length);
    if (pick >= folios.length)
    {
      pick = folios.length - 1;
    }
    folioPick = folios[pick];
  }
  
  return folioPick;
}