/**
* SearchHighlight plugin for jQuery
* 
* Thanks to Scott Yang <http://scott.yang.id.au/>
* for the original idea and some code
*    
* @author Renato Formato <renatoformato@virgilio.it> 
*  
* @version 0.33
*
*  Options
*  - exact (string, default:"exact") 
*    "exact" : find and highlight the exact words.
*    "whole" : find partial matches but highlight whole words
*    "partial": find and highlight partial matches
*     
*  - style_name (string, default:'hilite')
*    The class given to the span wrapping the matched words.
*     
*  - style_name_suffix (boolean, default:true)
*    If true a different number is added to style_name for every different matched word.
*     
*  - debug_referrer (string, default:null)
*    Set a referrer for debugging purpose.
*     
*  - engines (array of regex, default:null)
*    Add a new search engine regex to highlight searches coming from new search engines.
*    The first element is the regex to match the domain.
*    The second element is the regex to match the query string. 
*    Ex: [/^http:\/\/my\.site\.net/i,/search=([^&]+)/i]        
*            
*  - highlight (string, default:null)
*    A jQuery selector or object to set the elements enabled for highlight.
*    If null or no elements are found, all the document is enabled for highlight.
*        
*  - nohighlight (string, default:null)  
*    A jQuery selector or object to set the elements not enabled for highlight.
*    This option has priority on highlight. 
*    
*  - keys (string, default:null)
*    Disable the analisys of the referrer and search for the words given as argument    
*    
*/

(function($) {
    jQuery.fn.SearchHighlight = function(options) {
        var ref = options.debug_referrer || document.referrer;
        if (!ref && options.keys == undefined) return this;

        SearchHighlight.options = $.extend({ exact: "exact", style_name: 'hilite', style_name_suffix: true }, options);

        if (options.engines) SearchHighlight.engines.unshift(options.engines);
        var q = options.keys != undefined ? options.keys.toLowerCase().split(/[\s,\+\.]+/) : SearchHighlight.decodeURL(ref, SearchHighlight.engines);
        if (q && q.join("")) {
            SearchHighlight.buildReplaceTools(q);
            return this.each(function() {
                var el = this;
                if (el == document) el = $("body")[0];
                SearchHighlight.hiliteElement(el, q);
            })
        } else return this;
    }

    var SearchHighlight = {
        options: {},
        regex: [],
        engines: [
    [/^http:\/\/(www\.)?google\./i, /q=([^&]+)/i],                            // Google
    [/^http:\/\/(www\.)?search\.yahoo\./i, /p=([^&]+)/i],                     // Yahoo
    [/^http:\/\/(www\.)?search\.msn\./i, /q=([^&]+)/i],                       // MSN
    [/^http:\/\/(www\.)?search\.live\./i, /query=([^&]+)/i],                  // MSN Live
    [/^http:\/\/(www\.)?search\.aol\./i, /userQuery=([^&]+)/i],               // AOL
    [/^http:\/\/(www\.)?ask\.com/i, /q=([^&]+)/i],                            // Ask.com
    [/^http:\/\/(www\.)?altavista\./i, /q=([^&]+)/i],                         // AltaVista
    [/^http:\/\/(www\.)?feedster\./i, /q=([^&]+)/i],                          // Feedster
    [/^http:\/\/(www\.)?search\.lycos\./i, /q=([^&]+)/i],                     // Lycos
    [/^http:\/\/(www\.)?alltheweb\./i, /q=([^&]+)/i],                         // AllTheWeb
    [/^http:\/\/(www\.)?technorati\.com/i, /([^\?\/]+)(?:\?.*)$/i],           // Technorati
    ],
        subs: {},
        decodeURL: function(URL, reg) {
            URL = decodeURIComponent(URL);
            var query = null;
            $.each(reg, function(i, n) {
                if (n[0].test(URL)) {
                    var match = URL.match(n[1]);
                    if (match) {
                        query = match[1].toLowerCase();
                        return false;
                    }
                }
            })

            if (query) {
                query = query.replace(/(\'|")/, '\$1');
                query = query.split(/[\s,\+\.]+/);
            }

            return query;
        },
        regexAccent: [
      [/[\xC0-\xC5\u0100-\u0105]/ig, 'a'],
      [/[\xC7\u0106-\u010D]/ig, 'c'],
      [/[\xC8-\xCB]/ig, 'e'],
      [/[\xCC-\xCF]/ig, 'i'],
      [/\xD1/ig, 'n'],
      [/[\xD2-\xD6\xD8]/ig, 'o'],
      [/[\u015A-\u0161]/ig, 's'],
      [/[\u0162-\u0167]/ig, 't'],
      [/[\xD9-\xDC]/ig, 'u'],
      [/\xFF/ig, 'y'],
      [/[\x91\x92\u2018\u2019]/ig, '\'']
    ],
        matchAccent: /[\x91\x92\xC0-\xC5\xC7-\xCF\xD1-\xD6\xD8-\xDC\xFF\u0100-\u010D\u015A-\u0167\u2018\u2019]/ig,
        replaceAccent: function(q) {
            SearchHighlight.matchAccent.lastIndex = 0;
            if (SearchHighlight.matchAccent.test(q)) {
                for (var i = 0, l = SearchHighlight.regexAccent.length; i < l; i++)
                    q = q.replace(SearchHighlight.regexAccent[i][0], SearchHighlight.regexAccent[i][1]);
            }
            return q;
        },
        escapeRegEx: /((?:\\{2})*)([[\]{}*?|])/g, //the special chars . and + are already gone at this point because they are considered split chars
        buildReplaceTools: function(query) {
            var re = [], regex;
            $.each(query, function(i, n) {
                if (n = SearchHighlight.replaceAccent(n).replace(SearchHighlight.escapeRegEx, "$1\\$2"))
                    re.push(n);
            });

            regex = re.join("|");
            switch (SearchHighlight.options.exact) {
                case "exact":
                    regex = '\\b(?:' + regex + ')\\b';
                    break;
                case "whole":
                    regex = '\\b\\w*(' + regex + ')\\w*\\b';
                    break;
            }
            SearchHighlight.regex = new RegExp(regex, "gi");

            $.each(re, function(i, n) {
                SearchHighlight.subs[n] = SearchHighlight.options.style_name +
              (SearchHighlight.options.style_name_suffix ? i + 1 : '');
            });
        },
        nosearch: /s(?:cript|tyle)|textarea/i,
        hiliteElement: function(el, query) {
            var opt = SearchHighlight.options, elHighlight, noHighlight;
            elHighlight = opt.highlight ? $(opt.highlight) : $("#contentDivID");
            if (!elHighlight.length) elHighlight = $("#contentDivID");
            noHighlight = opt.nohighlight ? $(opt.nohighlight) : $([]);

            elHighlight.each(function() {
                SearchHighlight.hiliteTree(this, query, noHighlight);
            });
        },
        hiliteTree: function(el, query, noHighlight) {
            if (noHighlight.index(el) != -1) return;
            var matchIndex = SearchHighlight.options.exact == "whole" ? 1 : 0;
            for (var startIndex = 0, endIndex = el.childNodes.length; startIndex < endIndex; startIndex++) {
                var item = el.childNodes[startIndex];
                if (item.nodeType != 8) {//comment node
                    //text node
                    if (item.nodeType == 3) {
                        var text = item.data, textNoAcc = SearchHighlight.replaceAccent(text);
                        var newtext = "", match, index = 0;
                        SearchHighlight.regex.lastIndex = 0;
                        while (match = SearchHighlight.regex.exec(textNoAcc)) {
                            newtext += text.substr(index, match.index - index) + '<span class="' +
                SearchHighlight.subs[match[matchIndex].toLowerCase()] + '">' + text.substr(match.index, match[0].length) + "</span>";
                            index = match.index + match[0].length;
                        }
                        if (newtext) {
                            //add the last part of the text
                            newtext += text.substring(index);
                            var repl = $.merge([], $("<span>" + newtext + "</span>")[0].childNodes);
                            endIndex += repl.length - 1;
                            startIndex += repl.length - 1;
                            $(item).before(repl).remove();
                        }
                    } else {
                        if (item.nodeType == 1 && item.nodeName.search(SearchHighlight.nosearch) == -1)
                            SearchHighlight.hiliteTree(item, query, noHighlight);
                    }
                }
            }
        }
    };
})(jQuery)