jQuery.autocomplete = function(input, options) {

    // Create a link to self

    var me = this;



    // Create jQuery object for input element

    var $input = $(input).attr("autocomplete", "off");



    // Apply inputClass if necessary

    if (options.inputClass) $input.addClass(options.inputClass);



    // Create results

    var results = document.createElement("div");

    // Create jQuery object for results

    var $results = $(results);

    $results.hide().addClass(options.resultsClass).css("position", "absolute");

    if( options.width > 0 ) $results.css("width", options.width);



    // Add to body element

    $("body").append(results);



    input.autocompleter = me;



    var timeout = null;

    var prev = "";

    var active = -1;

    var cache = {};

    var keyb = false;

    var hasFocus = false;

    var lastKeyPressCode = null;



    // flush cache

    function flushCache(){

        cache = {};

        cache.data = {};

        cache.length = 0;

    };



    // flush cache

    flushCache();



    // if there is a data array supplied

    if( options.data != null ){

        var sFirstChar = "", stMatchSets = {}, row = [];



        // no url was specified, we need to adjust the cache length to make sure it fits the local data store

        if( typeof options.url != "string" ) options.cacheLength = 1;



        // loop through the array and create a lookup structure

        for( var i=0; i < options.data.length; i++ ){

            // if row is a string, make an array otherwise just reference the array

            row = ((typeof options.data[i] == "string") ? [options.data[i]] : options.data[i]);



            // if the length is zero, don't add to list

            if( row[0].length > 0 ){

                // get the first character

                sFirstChar = row[0].substring(0, 1).toLowerCase();

                // if no lookup array for this character exists, look it up now

                if( !stMatchSets[sFirstChar] ) stMatchSets[sFirstChar] = [];

                // if the match is a string

                stMatchSets[sFirstChar].push(row);

            }

        }



        // add the data items to the cache

        for( var k in stMatchSets ){

            // increase the cache size

            options.cacheLength++;

            // add to the cache

            addToCache(k, stMatchSets[k]);

        }

    }



    $input

    .keydown(function(e) {

        // track last key pressed

        lastKeyPressCode = e.keyCode;

        switch(e.keyCode) {

            case 38: // up

                e.preventDefault();

                moveSelect(-1);

                break;

            case 40: // down

                e.preventDefault();

                moveSelect(1);

                break;

            case 9:  // tab

            case 13: // return

                if( selectCurrent() ){

                    // make sure to blur off the current field

                    $input.get(0).blur();

                    e.preventDefault();

                    if($.browser.opera && e.keyCode == 13)

                        return false;

                }

                break;

            default:

                active = -1;

                if (timeout) clearTimeout(timeout);

                timeout = setTimeout(function(){
                    onChange();
                }, options.delay);

                break;

        }

    })

    .focus(function(){

        // track whether the field has focus, we shouldn't process any results if the field no longer has focus

        hasFocus = true;

    })

    .blur(function() {

        // track whether the field has focus

        hasFocus = false;

        hideResults();

    });



    hideResultsNow();



    function onChange() {

        // ignore if the following keys are pressed: [del] [shift] [capslock]

        if( lastKeyPressCode == 46 || (lastKeyPressCode > 8 && lastKeyPressCode < 32) ) return $results.hide();

        var v = $input.val();

        if (v == prev) return;

        prev = v;

        if (v.length >= options.minChars) {

            $input.addClass(options.loadingClass);

            requestData(v);

        } else {

            $input.removeClass(options.loadingClass);

            $results.hide();

        }

    };



    function moveSelect(step) {



        var lis = $("li", results);

        if (!lis) return;



        active += step;



        if (active < 0) {

            active = 0;

        } else if (active >= lis.size()) {

            active = lis.size() - 1;

        }



        lis.removeClass("ac_over");



        $(lis[active]).addClass("ac_over");



    // Weird behaviour in IE

    // if (lis[active] && lis[active].scrollIntoView) {

    // 	lis[active].scrollIntoView(false);

    // }



    };



    function selectCurrent() {

        var li = $("li.ac_over", results)[0];

        if (!li) {

            var $li = $("li", results);

            if (options.selectOnly) {

                if ($li.length == 1) li = $li[0];

            } else if (options.selectFirst) {

                li = $li[0];

            }

        }

        if (li) {

            selectItem(li);

            return true;

        } else {

            return false;

        }

    };



    function selectItem(li) {

        if (!li) {

            li = document.createElement("li");

            li.extra = [];

            li.selectValue = "";

        }

        var v = $.trim(li.selectValue ? li.selectValue : li.innerHTML);

        input.lastSelected = v;

        prev = v;

        $results.html("");

        $input.val(v);

        hideResultsNow();

        if (options.onItemSelect) setTimeout(function() {
            options.onItemSelect(li)
        }, 1);

    };



    // selects a portion of the input string

    function createSelection(start, end){

        // get a reference to the input element

        var field = $input.get(0);

        if( field.createTextRange ){

            var selRange = field.createTextRange();

            selRange.collapse(true);

            selRange.moveStart("character", start);

            selRange.moveEnd("character", end);

            selRange.select();

        } else if( field.setSelectionRange ){

            field.setSelectionRange(start, end);

        } else {

            if( field.selectionStart ){

                field.selectionStart = start;

                field.selectionEnd = end;

            }

        }

        field.focus();

    };



    // fills in the input box w/the first match (assumed to be the best match)

    function autoFill(sValue){

        // if the last user key pressed was backspace, don't autofill

        if( lastKeyPressCode != 8 ){

            // fill in the value (keep the case the user has typed)

            $input.val($input.val() + sValue.substring(prev.length));

            // select the portion of the value not typed by the user (so the next character will erase)

            createSelection(prev.length, sValue.length);

        }

    };



    function showResults() {

        // get the position of the input field right now (in case the DOM is shifted)

        var pos = findPos(input);

        // either use the specified width, or autocalculate based on form element

        var iWidth = (options.width > 0) ? options.width : $input.width();

        // reposition

        $results.css({

            width: parseInt(iWidth) + "px",

            top: (pos.y + input.offsetHeight) + "px",

            left: pos.x + "px"

        }).show();

    };



    function hideResults() {

        if (timeout) clearTimeout(timeout);

        timeout = setTimeout(hideResultsNow, 200);

    };



    function hideResultsNow() {

        if (timeout) clearTimeout(timeout);

        $input.removeClass(options.loadingClass);

        if ($results.is(":visible")) {

            $results.hide();

        }

        if (options.mustMatch) {

            var v = $input.val();

            if (v != input.lastSelected) {

                selectItem(null);

            }

        }

    };



    function receiveData(q, data) {

        if (data) {

            $input.removeClass(options.loadingClass);

            results.innerHTML = "";



            // if the field no longer has focus or if there are no matches, do not display the drop down

            if( !hasFocus || data.length == 0 ) return hideResultsNow();



            if ($.browser.msie) {

                // we put a styled iframe behind the calendar so HTML SELECT elements don't show through

                $results.append(document.createElement('iframe'));

            }

            results.appendChild(dataToDom(data));

            if( (options.maxItemsToShow > 0) && (options.maxItemsToShow < data.length) && options.maxItemsMessage) {

                var tmp = document.createElement('div');

                tmp.innerHTML = options.maxItemsMessage;

                $results.append(tmp);

            }

            // autofill in the complete box w/the first match as long as the user hasn't entered in more data

            if( options.autoFill && ($input.val().toLowerCase() == q.toLowerCase()) ) autoFill(data[0][0]);

            showResults();
                        
            if(data.length == 1){
                selectCurrent();
            }

        } else {

            hideResultsNow();

        }

    };



    function parseData(data) {

        if (!data) return null;

        var parsed = [];

        var rows = data.split(options.lineSeparator);

        for (var i=0; i < rows.length; i++) {

            var row = $.trim(rows[i]);

            if (row) {

                parsed[parsed.length] = row.split(options.cellSeparator);

            }

        }

        return parsed;

    };



    function dataToDom(data) {

        var ul = document.createElement("ul");

        var num = data.length;



        // limited results to a max number

        if( (options.maxItemsToShow > 0) && (options.maxItemsToShow < num) ) num = options.maxItemsToShow;



        for (var i=0; i < num; i++) {

            var row = data[i];

            if (!row) continue;

            var li = document.createElement("li");

            if (options.formatItem) {

                li.innerHTML = options.formatItem(row, i, num);

                li.selectValue = row[0];

            } else {

                li.innerHTML = row[0];

                li.selectValue = row[0];

            }

            var extra = null;

            if (row.length > 1) {

                extra = [];

                for (var j=1; j < row.length; j++) {

                    extra[extra.length] = row[j];

                }

            }

            li.extra = extra;

            ul.appendChild(li);

            $(li).hover(

                function() {
                    $("li", ul).removeClass("ac_over");
                    $(this).addClass("ac_over");
                    active = $("li", ul).indexOf($(this).get(0));
                },

                function() {
                    $(this).removeClass("ac_over");
                }

                ).click(function(e) {
                e.preventDefault();
                e.stopPropagation();
                selectItem(this)
            });

        }

        return ul;

    };



    function requestData(q) {

        if (!options.matchCase) q = q.toLowerCase();

        var data = options.cacheLength ? loadFromCache(q) : null;

        // recieve the cached data

        if (data) {

            receiveData(q, data);

        // if an AJAX url has been supplied, try loading the data now

        } else if( (typeof options.url == "string") && (options.url.length > 0) ){

            $.get(makeUrl(q), function(data) {

                data = parseData(data);

                addToCache(q, data);

                receiveData(q, data);

            });

        // if there's been no data found, remove the loading class

        } else {

            $input.removeClass(options.loadingClass);

        }

    };



    function makeUrl(q) {

        var url = options.url + "?q=" + encodeURI(q);

        for (var i in options.extraParams) {

            url += "&" + i + "=" + encodeURI(options.extraParams[i]);

        }

        return url;

    };



    function loadFromCache(q) {

        if (!q) return null;

        if (cache.data[q]) return cache.data[q];

        if (options.matchSubset) {

            for (var i = q.length - 1; i >= options.minChars; i--) {

                var qs = q.substr(0, i);

                var c = cache.data[qs];

                if (c) {

                    var csub = [];

                    for (var j = 0; j < c.length; j++) {

                        var x = c[j];

                        var x0 = x[0];

                        if (matchSubset(x0, q)) {

                            csub[csub.length] = x;

                        }

                    }

                    return csub;

                }

            }

        }

        return null;

    };



    function matchSubset(s, sub) {

        if (!options.matchCase) s = s.toLowerCase();

        var i = s.indexOf(sub);

        if (i == -1) return false;

        return i == 0 || options.matchContains;

    };



    this.flushCache = function() {

        flushCache();

    };



    this.setExtraParams = function(p) {

        options.extraParams = p;

    };



    this.findValue = function(){

        var q = $input.val();



        if (!options.matchCase) q = q.toLowerCase();

        var data = options.cacheLength ? loadFromCache(q) : null;

        if (data) {

            findValueCallback(q, data);

        } else if( (typeof options.url == "string") && (options.url.length > 0) ){

            $.get(makeUrl(q), function(data) {

                data = parseData(data)

                addToCache(q, data);

                findValueCallback(q, data);

            });

        } else {

            // no matches

            findValueCallback(q, null);

        }

    }



    function findValueCallback(q, data){

        if (data) $input.removeClass(options.loadingClass);



        var num = (data) ? data.length : 0;

        var li = null;



        for (var i=0; i < num; i++) {

            var row = data[i];



            if( row[0].toLowerCase() == q.toLowerCase() ){

                li = document.createElement("li");

                if (options.formatItem) {

                    li.innerHTML = options.formatItem(row, i, num);

                    li.selectValue = row[0];

                } else {

                    li.innerHTML = row[0];

                    li.selectValue = row[0];

                }

                var extra = null;

                if( row.length > 1 ){

                    extra = [];

                    for (var j=1; j < row.length; j++) {

                        extra[extra.length] = row[j];

                    }

                }

                li.extra = extra;

            }

        }



        if( options.onFindValue ) setTimeout(function() {
            options.onFindValue(li)
        }, 1);

    }



    function addToCache(q, data) {

        if (!data || !q || !options.cacheLength) return;

        if (!cache.length || cache.length > options.cacheLength) {

            flushCache();

            cache.length++;

        } else if (!cache[q]) {

            cache.length++;

        }

        cache.data[q] = data;

    };



    function findPos(obj) {

        var curleft = obj.offsetLeft || 0;

        var curtop = obj.offsetTop || 0;

        while (obj = obj.offsetParent) {

            curleft += obj.offsetLeft

            curtop += obj.offsetTop

        }

        return {
            x:curleft,
            y:curtop
        };

    }

}



jQuery.fn.autocomplete = function(url, options, data) {

    // Make sure options exists

    options = options || {};

    // Set url as option

    options.url = url;

    // set some bulk local data

    options.data = ((typeof data == "object") && (data.constructor == Array)) ? data : null;



    // Set default values for required options

    options.inputClass = options.inputClass == undefined ? "ac_input" : options.inputClass;

    options.resultsClass = options.resultsClass == undefined ? "ac_results" : options.resultsClass;

    options.lineSeparator = options.lineSeparator == undefined ? "\n" : options.lineSeparator;

    options.cellSeparator = options.cellSeparator == undefined ? "|" : options.cellSeparator;

    options.minChars = options.minChars == undefined ? 1 : options.minChars;

    options.delay = options.delay == undefined ? 400 : options.delay;

    options.matchCase = options.matchCase == undefined ? 0 : options.matchCase;

    options.matchSubset = options.matchSubset == undefined ? 1 : options.matchSubset;

    options.matchContains = options.matchContains == undefined ? 0 : options.matchContains;

    options.cacheLength = options.cacheLength == undefined ? 1 : options.cacheLength;

    options.mustMatch = options.mustMatch == undefined ? 0 : options.mustMatch;

    options.extraParams = options.extraParams == undefined ? {} : options.extraParams;

    options.loadingClass = options.loadingClass == undefined ? "ac_loading" : options.loadingClass;

    options.selectFirst = options.selectFirst == undefined ? false : options.selectFirst;

    options.selectOnly = options.selectOnly == undefined ? false : options.selectOnly;

    options.maxItemsToShow = options.maxItemsToShow == undefined ? -1 : options.maxItemsToShow;

    options.autoFill = options.autoFill == undefined ? false : options.autoFill;

    options.width = options.width == undefined ? 0 : parseInt(options.width, 10) || 0;



    this.each(function() {

        var input = this;

        new jQuery.autocomplete(input, options);

    });



    // Don't break the chain

    return this;

}



jQuery.fn.autocompleteArray = function(data, options) {

    return this.autocomplete(null, options, data);

}



jQuery.fn.indexOf = function(e){

    for( var i=0; i<this.length; i++ ){

        if( this[i] == e ) return i;

    }

    return -1;

};