/* http://www.kryogenix.org/code/browser/searchhi/ */
/* Modified 20021006 to fix query string parsing and add case insensitivity */
/* Modified 20070316 to stop highlighting inside nosearchhi nodes */
function highlightWord(node,word) {
        // Iterate into this nodes childNodes
        if (node.hasChildNodes) {
                var hi_cn;
                for (hi_cn=0;hi_cn<node.childNodes.length;hi_cn++) {
                        highlightWord(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;
                        // check if we're inside a "nosearchhi" zone
                        checkn = pn;
                        while (checkn.nodeType != 9 &&
                        checkn.nodeName.toLowerCase() != 'body') {
                        // 9 = top of doc
                                if (checkn.className.match(/\bnosearchhi\b/)) { return; }
                                checkn = checkn.parentNode;
                        }
                        if (pn.className != "searchmark") {
                                // word has not already been 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("span");
                                hiword.className = "searchmark";
                                hiword.appendChild(hiwordtext);
                                pn.insertBefore(before,node);
                                pn.insertBefore(hiword,node);
                                pn.insertBefore(after,node);
                                pn.removeChild(node);
                        }
                }
        }
}

function googleSearchHighlight() {
        if (!document.createElement) return;
        ref = document.referrer;
        if (ref.indexOf('?') == -1) return;
        qs = ref.substr(ref.indexOf('?')+1);
        qsa = qs.split('&');
        for (i=0;i<qsa.length;i++) {
                qsip = qsa[i].split('=');
                if (qsip.length == 1) continue;
                if (qsip[0] == 'q' || qsip[0] == 'query' || qsip[0] == 'p') {
                 // q= for Google, p= for Yahoo
                        words = unescape(qsip[1].replace(/\+/g,' ')).split(/\s+/);
                        for (w=0;w<words.length;w++) {
                                highlightWord(document.getElementsByTagName("body")[0],words[w]);
                        }
                }
        }
}

window.onload = googleSearchHighlight;