function doHighlight(bodyText, searchTerm, highlightStartTag, highlightEndTag) 
{
  if ((!highlightStartTag) || (!highlightEndTag)) 
  {
    highlightStartTag = "<font style='color:blue; background-color:yellow;'>";
    highlightEndTag = "</font>";
  }
  
  var newText = "";
  var i = -1;
  var lcSearchTerm = searchTerm.toLowerCase();
  var lcBodyText = bodyText.toLowerCase();
    
  while (bodyText.length > 0) 
  {
    i = lcBodyText.indexOf(lcSearchTerm, i+1);
    if (i < 0) 
    {
      newText += bodyText;
      bodyText = "";
    } else 
    {
      if (bodyText.lastIndexOf(">", i) >= bodyText.lastIndexOf("<", i)) 
      {
        if (lcBodyText.lastIndexOf("/script>", i) >= lcBodyText.lastIndexOf("<script", i)) 
        {
          newText += bodyText.substring(0, i) + highlightStartTag + bodyText.substr(i, searchTerm.length) + highlightEndTag;
          bodyText = bodyText.substr(i + searchTerm.length);
          lcBodyText = bodyText.toLowerCase();
          i = -1;
        }
      }
    }
  }  
  return newText;
}

function highlightSearchTerms(searchText, treatAsPhrase, highlightStartTag, highlightEndTag)
{
  if (treatAsPhrase) 
  {
    searchArray = [searchText];
  } else 
  {
    searchArray = searchText.split(" ");
  }
  
  if (!document.body || typeof(document.body.innerHTML) == "undefined") 
  {
    return false;
  }
  
  var bodyText = document.getElementById("searchArea").innerHTML;
  
  for (var i = 0; i < searchArray.length; i++) 
  {
    bodyText = doHighlight(bodyText, searchArray[i], highlightStartTag, highlightEndTag);
  }
  
  document.getElementById("searchArea").innerHTML = bodyText;
  return true;
}

function searchPrompt(defaultText, textColor, bgColor)
{
  if (!defaultText)
    defaultText = "";
  
  if ((!textColor) || (!bgColor)) 
  {
    highlightStartTag = "";
    highlightEndTag = "";
  } 
  else 
  {
    highlightStartTag = "<font style='color:" + textColor + "; background-color:" + bgColor + ";'>";
    highlightEndTag = "</font>";
  }
  
  searchText = prompt("Wpisz szukany tekst:", defaultText);
  
  return highlightSearchTerms(searchText, false, true, highlightStartTag, highlightEndTag);
}