/*
** Modified TOC script from http://www.quirksmode.org/
*/
function createTOC()
{
    var x = document.getElementById('texts').childNodes;
    var y = document.createElement('div');
    y.id = 'toc';
    y.onclick = showhideTOC;
    var a = y.appendChild(document.createElement('span'));
    a.innerHTML = 'Chapter Contents';
    var z = y.appendChild(document.createElement('div'));
    z.id = 'toc-list';
    
    var toBeTOCced = new Array();
    for (var i=0; i<x.length; i++)
    {
        if (
            x[i].nodeName.indexOf('H') != -1 // tag name has 'H'
            &&
            x[i].nodeName.indexOf('HR') == -1 // but is not a horizontal rule
           )
        {
            toBeTOCced.push(x[i])
        }
    }

    if (toBeTOCced.length < 2) return false;

    for (var i=0; i<toBeTOCced.length; i++)
    {
        var tmp = document.createElement('a');
        tmp.innerHTML = toBeTOCced[i].innerHTML;
        tmp.href = '#toc-link' + i;
        tmp.className = 'page';
        z.appendChild(tmp);
        if (toBeTOCced[i].nodeName == 'H3')
            tmp.className += ' indent';
        var tmp2 = document.createElement('a');
        tmp2.id = 'toc-link' + i;
        if (toBeTOCced[i].nodeName == 'H1')
        {
            tmp.innerHTML = 'Top';
            tmp.href = '#toc-top';
            tmp2.id = 'toc-top';
        }
        toBeTOCced[i].parentNode.insertBefore(tmp2, toBeTOCced[i]);
    }
    document.body.insertBefore(y, document.body.childNodes[2]);
    return true;
}
var TOCstate = 'none';
function showhideTOC()
{
    TOCstate = (TOCstate == 'none') ? 'block' : 'none';
    document.getElementById('toc').lastChild.style.display = TOCstate;
}

function showPrintThisPage()
{
    var x = document.getElementById('texts');
    var y = document.createElement('div');
    y.id = 'print-page';
    y.innerHTML = '<span onclick="window.print();" title="Print a printer-friendly version of this page.">Print this Chapter</span>';
    x.appendChild(y);
}

function showToPageTop()
{
    var x = document.getElementById('texts');
    var y = document.createElement('div');
    y.id = 'totop-fixed';
    y.innerHTML = '<a href="#hdr" title="Go to the top of this page.">Top &uarr;</a>';
    x.appendChild(y);
}

// detect IE 5.2 for Mac
var ieMac = (
    navigator.userAgent.indexOf('MSIE 5.2') != -1
    &&
    navigator.userAgent.indexOf('Mac') != -1
);
// detect IE/Win
var ieWin = ( navigator.userAgent.indexOf('MSIE') != -1 )

window.onload = function()
{
    if (top.ieMac) return; // don't do any of this for IE/Mac
    showPrintThisPage();
    if (!createTOC()) document.getElementById('print-page').style.right = '0px';
    showToPageTop();
}

/*
 * This is the function that actually highlights a text string by
 * adding HTML tags before and after all occurrences of the search
 * term. You can pass your own tags if you'd like, or if the
 * highlightStartTag or highlightEndTag parameters are omitted or
 * are empty strings then the default <font> tags will be used.
 */
function doHighlight(bodyText, searchTerm, highlightStartTag, highlightEndTag) 
{
  // the highlightStartTag and highlightEndTag parameters are optional
  if ((!highlightStartTag) || (!highlightEndTag)) {
    highlightStartTag = "<font style='color:blue; background-color:yellow;'>";
    highlightEndTag = "</font>";
  }
  
  // find all occurences of the search term in the given text,
  // and add some "highlight" tags to them (we're not using a
  // regular expression search, because we want to filter out
  // matches that occur within HTML tags and script blocks, so
  // we have to do a little extra validation)
  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 {
      // skip anything inside an HTML tag
      if (bodyText.lastIndexOf(">", i) >= bodyText.lastIndexOf("<", i)) {
        // skip anything inside a <script> block
        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;
}


/*
 * This is sort of a wrapper function to the doHighlight function.
 * It takes the searchText that you pass, optionally splits it into
 * separate words, and transforms the text on the current web page.
 * Only the "searchText" parameter is required; all other parameters
 * are optional and can be omitted.
 */
function highlightSearchTerms(searchText, treatAsPhrase, warnOnFailure, highlightStartTag, highlightEndTag)
{
  // if the treatAsPhrase parameter is true, then we should search for 
  // the entire phrase that was entered; otherwise, we will split the
  // search string so that each word is searched for and highlighted
  // individually
  if (treatAsPhrase) {
    searchArray = [searchText];
  } else {
    searchArray = searchText.split(" ");
  }
  
  if (!document.body || typeof(document.body.innerHTML) == "undefined") {
    if (warnOnFailure) {
      alert("Sorry, for some reason the text of this page is unavailable. Searching will not work.");
    }
    return false;
  }
  
  var bodyText = document.body.innerHTML;
  for (var i = 0; i < searchArray.length; i++) {
    bodyText = doHighlight(bodyText, searchArray[i], highlightStartTag, highlightEndTag);
  }
  
  document.body.innerHTML = bodyText;
  return true;
}


/*
 * This displays a dialog box that allows a user to enter their own
 * search terms to highlight on the page, and then passes the search
 * text or phrase to the highlightSearchTerms function. All parameters
 * are optional.
 */
function searchPrompt(defaultText, treatAsPhrase, textColor, bgColor)
{
  // This function prompts the user for any words that should
  // be highlighted on this web page
  if (!defaultText) {
    defaultText = "";
  }
  
  // we can optionally use our own highlight tag values
  if ((!textColor) || (!bgColor)) {
    highlightStartTag = "";
    highlightEndTag = "";
  } else {
    highlightStartTag = "<font style='color:" + textColor + "; background-color:" + bgColor + ";'>";
    highlightEndTag = "</font>";
  }
  
  if (treatAsPhrase) {
    promptText = "Please enter the phrase you'd like to search for:";
  } else {
    promptText = "Please enter the words you'd like to search for, separated by spaces:";
  }
  
  searchText = prompt(promptText, defaultText);

  if (!searchText)  {
    alert("No search terms were entered. Exiting function.");
    return false;
  }
  
  return highlightSearchTerms(searchText, treatAsPhrase, true, highlightStartTag, highlightEndTag);
}


/*
 * This function takes a referer/referrer string and parses it
 * to determine if it contains any search terms. If it does, the
 * search terms are passed to the highlightSearchTerms function
 * so they can be highlighted on the current page.
 */
function highlightGoogleSearchTerms(referrer)
{
  // This function has only been very lightly tested against
  // typical Google search URLs. If you wanted the Google search
  // terms to be automatically highlighted on a page, you could
  // call the function in the onload event of your <body> tag, 
  // like this:
  //   <body onload='highlightGoogleSearchTerms(document.referrer);'>
  
  //var referrer = document.referrer;
  if (!referrer) {
    return false;
  }
  
  var queryPrefix = "q=";
  var startPos = referrer.toLowerCase().indexOf(queryPrefix);
  if ((startPos < 0) || (startPos + queryPrefix.length == referrer.length)) {
    return false;
  }
  
  var endPos = referrer.indexOf("&", startPos);
  if (endPos < 0) {
    endPos = referrer.length;
  }
  
  var queryString = referrer.substring(startPos + queryPrefix.length, endPos);
  // fix the space characters
  queryString = queryString.replace(/%20/gi, " ");
  queryString = queryString.replace(/\+/gi, " ");
  // remove the quotes (if you're really creative, you could search for the
  // terms within the quotes as phrases, and everything else as single terms)
  queryString = queryString.replace(/%22/gi, "");
  queryString = queryString.replace(/\"/gi, "");
  
  return highlightSearchTerms(queryString, false);
}


/*
 * This function is just an easy way to test the highlightGoogleSearchTerms
 * function.
 */
function testHighlightGoogleSearchTerms()
{
	var xxxx = document.URL;
  var referrerString = xxxx;
  //referrerString = prompt("Test the following referrer string:", referrerString);
  return highlightGoogleSearchTerms(referrerString);
}

var xxxx = document.URL;
//alert(xxxx);
//window.onload = testHighlightGoogleSearchTerms();

//var oldLoad = window.onload;
//window.onload=function(){
// testHighlightGoogleSearchTerms();
//}