Highlighten search term

/*     HIGHLIGHTEN von Suchbegriffen aus GOOGLE, YAHOO, MSN, Bing, Zoom-Indexer, .....       */


var ref = "";


function highlightTerm(node,word) {

	if (node.hasChildNodes) {
		var hi_cn;
		for (hi_cn=0;hi_cn<node.childNodes.length;hi_cn++) {
			highlightTerm(node.childNodes[hi_cn],word);
		}
	}

	// And do this node itself
	if (node.nodeType == 3) { // text node
		tempNodeVal = node.nodeValue.toLowerCase();
		tempWordVal = word.toLowerCase();
		if (tempNodeVal.indexOf(tempWordVal) != -1) {
			pn = node.parentNode;
			klasse = "searchword"+w; // verschiedene Farben für versch. keywords


			if (pn.className != klasse) {
				// keyword noch nicht highlighted!
				nv = node.nodeValue;
				ni = tempNodeVal.indexOf(tempWordVal);
				// Create a load of replacement nodes
				before = document.createTextNode(nv.substr(0,ni));
				docWordVal = nv.substr(ni,word.length);
				after = document.createTextNode(nv.substr(ni+word.length));
				hiwordtext = document.createTextNode(docWordVal);
				hiword = document.createElement("em"); 


				hiword.className = klasse;
				hiword.appendChild(hiwordtext);
				pn.insertBefore(before,node);
				pn.insertBefore(hiword,node);
				pn.insertBefore(after,node);
				pn.removeChild(node);
			}
		}
	}
}


function Highlight() {
	if (!document.createElement) return;

	if (window.location.search) ref = unescape(window.location.search);


	if (document.referrer.search(/google.+/) != -1 				// Google
		|| document.referrer.search(/bing.+/) != -1 			// Bing
		|| document.referrer.search(/zoom.+/) != -1 			// Zomm Indexer
		|| document.referrer.search(/lycos.+/) != -1 			// Lycos
		|| document.referrer.search(/yahoo.+/) != -1 			// Yahoo
		|| document.referrer.search(/fireball.+/) != -1 		        // Fireball
		|| document.referrer.search(/search\.msn.+/) != -1 ) {	// MSN

		// ref = decodeURIComponent(document.referrer); geht nur mit UTF-8 codiertem String
		// ref = unescape(document.referrer); geht auch nur teilweise
		ref = decodeURIComponent(document.referrer);

		if (ref.indexOf('?') == -1) return;
	}


	// Für Seitensuche:

	if (document.referrer.search(/suchen.+/) != -1 && document.URL.indexOf("suchen") == -1 ) {
		ref = unescape(document.referrer);	
		if (window.location.search) ref = unescape(window.location.search);
	}


	//if (ref.indexOf('?') == -1) return;


	qs = ref.substr(ref.indexOf('?')+1);


        qs = qs.replace(/\.|,|;|!|\?|:|"|'|\//gi,'');
	qsa = qs.split('&');


	for (i=0;i<qsa.length;i++) {
		qsip = qsa[i].split('=');
	        if (qsip.length == 1 || qsip.length == 5) continue;
        	if (qsip[0] == 'q' 				// q = Google, Bing
        		|| qsip[0] == 'query' 		       // query = Fireball, Lycos
        		|| qsip[0] == 'zoom_query' 	       // zoom-query = Zoom Indexer
        		|| qsip[0] == 'p' 			// p = Yahoo
        		|| qsip[0] == 's' ) { 		       // s = Wordpress
	        if (qsip[1].length < 3 ) continue;


			// keywords nicht highlighten:
			qsip[1] = qsip[1].replace(/\"|\'|\*|;|\bbei\b|\bfür\b|\bvon\b|\bnicht\b|\bde.\s*\b|\bdie\b|\bdas\b|\bauf\b|\bein\b|\bund\b|\bwie\b|\bkann\b|\bich\b|\bman\b|\bmit\b|\ist\b|Suchbegriff/gi,'');

			qsip[1] = qsip[1].replace(/Suchbegriff/gi,'');
                        if (document.URL.indexOf('blog') >= 1) qsip[1] = qsip[1].replace(/\d\d|\d/g,''); // 1/2-digit number in blogs

			// remove all blanks and '+' before and after searchterm (bugfix: crashes FF & Op)
			qsip[1] = qsip[1].replace(/^(\s+|\++)/,'').replace(/(\++)$/,'').replace(/(\s+)$/,'');

			if (qsip[1] != '') {
			words = unescape(qsip[1].replace(/\+/g,' ')).split(/\s+/);
				for (w=0;w<words.length;w++) {
					if (words[w].length >= 3) {
                                  // Endlosschleife: words[w] = words[w].replace(/\.|,|;|!|\?|:|"|'|-|\//gi,'');
					    highlightTerm(document.getElementsByTagName("body")[0],words[w]);
					}
                		}
			}
	        }
	}
}