window.highlighter = new SearchTermHighlighter();

highlighter.init();

function SearchTermHighlighter()
{
	var ok = ((document.createElement) ? true : false);
	var isInitialized = false;
	var searchTerms = new Array();
	var foundCount = 0;
	var styles = new Array();
	var usingDefaultStyles = true;
	var DEBUG = false;
	var mySearch = ''; // this line added for AuthorIT Search - Rhonda Bracey, Dec 2005

	this.parameters = 'q as_q as_epq as_oq query search';
	this.legend = true;
	this.addStyle = addStyle;
	this.init = init;
	this.loadSearchTerms = loadSearchTerms;
	this.highlight = highlight;
	this.highlightTerm = highlightTerm;
	this.writeLegend = writeLegend;
	this.hideLegend = hideLegend;
	this.unhighlight = unhighlight;
	
	if (!ok) return;
	loadDefaults();

	function loadDefaults()
	{
		var liteBG = '#FF6 #BFF #9F9 #F99 #F6F'.split(/ /);
		var darkBG = '#800 #0A0 #860 #049 #909'.split(/ /);
		for (var i = 0; i < liteBG.length; i++){styles.push(new HighlightStyle('black', liteBG[i], 'bold'));}
		for (i = 0; i < darkBG.length; i++){styles.push(new HighlightStyle('white', darkBG[i], 'bold'));}
	}

	function addStyle(color, background, fontWeight)
	{
		if (!ok) return;
		if (usingDefaultStyles) { styles = new Array(); usingDefaultStyles = false; }
		styles.push(new HighlightStyle(color, background, fontWeight));
	}

	function init()
	{
		var s = '';
		if(null != top.frames["TOC"]) {
			o = top.frames["TOC"].document.getElementById('SearchTextH');
			if(null != o) {
				s = o.value;
			}
		}
		this.mySearch='file://?search='+s;
		
		if (!ok) return;
		this.loadSearchTerms();
		var style = 0;
		document.write('<style type="text/css">\n');
		for (i = 0; i < searchTerms.length; i++)
		{
			document.write('.' + searchTerms[i].cssClass + '{' + styles[style] + '}\n');
			style++;
			if (style >= styles.length) style = 0;
		}
		if (this.legend) document.write('#sth_legend{border:1px solid #CCC;background:white;margin:0px;padding:5px;' 
			+ 'font-family:verdana,helvetica,arial,sans-serif;font-size:x-small;}\n');
		document.write('</style>\n');
		isInitialized = true;
	}

	function loadSearchTerms()
	{
		
		var a = new Array();
		//var params = getParamValues(document.referrer, this.parameters); ---- line removed for AuthorIT Search - Rhonda Bracey, Dec 2005
		var params = getParamValues(this.mySearch, this.parameters); // line added for AuthorIT Search - Rhonda Bracey, Dec 2005
		var terms;
		var index = 0;
		for (i = 0; i < params.length; i++)
		{
			terms = parseTerms(params[i]);
			for (j = 0; j < terms.length; j++)
			{
				if (terms[j] != '')
				{
					a.push(new SearchTerm(index++, terms[j].toLowerCase()));
				}
			}
		}
		
		a.sort(function(t1, t2){return ((t1.term == t2.term) ? 0 : ((t1.term < t2.term) ? -1 : 1));});
		var prev = new SearchTerm(0, '');
		for (i = a.length - 1; i >= 0; i--)
		{
			if (a[i].term != prev.term)
			{
				searchTerms.push(a[i]);
				prev = a[i];
			}
		}
		searchTerms.sort(function(t1, t2){return t1.index - t2.index;});
		debugAlert('Search Terms:\n' + searchTerms.join('\n'));
	}
	
	function parseTerms (query)
	{
		var s = query + '';
		s = s.replace(/(^|\s)(site|related|link|info|cache):[^\s]*(\s|$)/ig, ' ');
		s = s.replace(/[^a-z0-9_-]/ig, ' '); // word chars only.
		s = s.replace(/(^|\s)-/g, ' '); // +required -excluded ~synonyms
		s = s.replace(/\b(and|not|or)\b/ig, ' ');
		s = s.replace(/\b[a-z0-9]\b/ig, ' '); // one char terms
		return s.split(/\s+/);
	}

	function getParamValues(url, parameters)
	{
		var params = new Array();
		var p = parameters.replace(/,/, ' ').split(/\s+/);
		if (url.indexOf('?') > 0)
		{
			var qs = url.substr(url.indexOf('?') + 1);
			var qsa = qs.split('&');
			for (i = 0; i < qsa.length; i++) 
			{
				nameValue = qsa[i].split('=');
				if (nameValue.length != 2) continue;
				for (j = 0; j < p.length; j++)
				{
					if (nameValue[0] == p[j])
					{
						params.push(unescape(nameValue[1]).toLowerCase().replace(/\+/g, ' '));
					}
				}
			}
		}
		return params;
	}

	function highlight() 
	{
		if (!ok) return;
		if (!isInitialized) this.init();
		searchTerms.sort(function(term1, term2){return(term2.term.length-term1.term.length)});
		for (var i = 0; i < searchTerms.length; i++)
		{
			this.highlightTerm(document.getElementsByTagName("body")[0], searchTerms[i]);
		}
		if (this.legend)
		{
			this.writeLegend();
		}
	}
	
	function highlightTerm(node, term) 
	{
		// this little step is required to prevent IE from getting wrapped around the axle on 
		// certain types of malformed HTML.
		if (node.nodeType == 1) // element
		{
			if (node.getAttribute("sth_x") == term.term) return;
			else node.setAttribute("sth_x", term.term);
		}
		
		if (node.hasChildNodes())
		{
			for (var i = 0; i < node.childNodes.length; i++) 
			{
				this.highlightTerm(node.childNodes[i], term);
			}
		}

		if (node.nodeType == 3)
		{
			var p = node.parentNode;
			if (p.nodeName != 'TEXTAREA' && p.nodeName != 'SCRIPT' && p.className.substr(0, term.CSS_CLASS_PREFIX.length) != term.CSS_CLASS_PREFIX)
			{
				var result = term.pattern.exec(node.nodeValue);
				if (result != null)
				{
					term.found = true;
					foundCount++;
					var v = node.nodeValue;
					var lt = document.createTextNode(v.substr(0, result.index));
					var rt = document.createTextNode(v.substr(result.index + result[0].length));
					var span = document.createElement('SPAN');
					span.className = term.cssClass;
					span.appendChild(document.createTextNode(result[0]));
					p.insertBefore(lt, node);
					p.insertBefore(span, node);
					p.replaceChild(rt, node);
				}
			}
		}
	}

	function writeLegend()
	{
		if (foundCount > 0)
		{
			var body = document.getElementsByTagName("body")[0];
			var legend = body.insertBefore(document.createElement('DIV'), body.childNodes[0]);
			legend.id = 'sth_legend';
			var s = 'These search terms have been highlighted:';
			searchTerms.sort(function(t1, t2){return t1.index - t2.index;});
			for (var i = 0; i < searchTerms.length; i++)
			{
				if (searchTerms[i].found == true) s += ' <span class="' + searchTerms[i].cssClass + '">' 
					+ searchTerms[i].term + '</span>';
			}
			s += ' | <a href="javascript:void(0);" onclick="highlighter.hideLegend()">hide this legend</a>';
			s += ' | <a href="javascript:void(0);" onclick="highlighter.unhighlight()">remove highlighting</a>';
			legend.innerHTML = s;
		}
	}
	
	function hideLegend()
	{
		var legend = document.getElementById('sth_legend');
		if (legend) legend.parentNode.removeChild(legend);
	}

	function unhighlight()
	{
		var prefix = searchTerms[0].CSS_CLASS_PREFIX;
		var spans = document.getElementsByTagName('SPAN');
		var elts = new Array();
		var parent, i, j;
		for (i = 0; i < spans.length; i++)
		{
			if (spans[i].className.substr(0, prefix.length) == prefix)
			{
				elts.push(spans[i]);
			}
		}
		for (i = 0; i < elts.length; i++)
		{
			parent = elts[i].parentNode;
			for (j = 0; j < elts[i].childNodes.length; j++)
			{
				parent.insertBefore(elts[i].childNodes[j], elts[i]);
			}
			parent.removeChild(elts[i]);
		}
		this.hideLegend();
	}

	function debugAlert(msg){if(DEBUG)alert(msg);}

	function SearchTerm(index, term)
	{
		this.CSS_CLASS_PREFIX = 'sth_';
		this.index = index;
		this.term = term.toLowerCase();
		this.cssClass = this.CSS_CLASS_PREFIX + this.term.replace(/[^a-z0-9_ ]/g, '').replace(/ /g, '_');
		this.pattern = new RegExp('' + this.term + '', 'i'); 
		this.found = false;
		this.toString = function(){return this.term};
	}

	function HighlightStyle(color, background, fontWeight)
	{
		this.color = color;
		this.background = background;
		this.fontWeight = fontWeight;
		this.toString = function(){return 'color:' + this.color + ';background:' 
			+ this.background + ';font-weight:' + this.fontWeight + ';'};
	}
}