apps/wolnelektury_core/static/js/jquery.autocomplete.js

   1 /*
   2  * jQuery Autocomplete plugin 1.1
   3  *
   4  * Copyright (c) 2009 Jörn Zaefferer
   5  *
   6  * Dual licensed under the MIT and GPL licenses:
   7  *   http://www.opensource.org/licenses/mit-license.php
   8  *   http://www.gnu.org/licenses/gpl.html
   9  *
  10  * Revision: $Id: jquery.autocomplete.js 15 2009-08-22 10:30:27Z joern.zaefferer $
  11  */
  12
  13 /*
  14  * Modified by Radek Czajka, Fundacja Nowoczesna Polska, 2010-05-10:
  15  *   escape regex for word start checking in matchSubset
  16  */
  17
  18 ;(function($) {
  19
  20 $.fn.extend({
  21         autocomplete: function(urlOrData, options) {
  22                 var isUrl = typeof urlOrData == "string";
  23                 options = $.extend({}, $.Autocompleter.defaults, {
  24                         url: isUrl ? urlOrData : null,
  25                         data: isUrl ? null : urlOrData,
  26                         delay: isUrl ? $.Autocompleter.defaults.delay : 10,
  27                         max: options && !options.scroll ? 10 : 150
  28                 }, options);
  29
  30                 // if highlight is set to false, replace it with a do-nothing function
  31                 options.highlight = options.highlight || function(value) { return value; };
  32
  33                 // if the formatMatch option is not specified, then use formatItem for backwards compatibility
  34                 options.formatMatch = options.formatMatch || options.formatItem;
  35
  36                 return this.each(function() {
  37                         new $.Autocompleter(this, options);
  38                 });
  39         },
  40         result: function(handler) {
  41                 return this.bind("result", handler);
  42         },
  43         search: function(handler) {
  44                 return this.trigger("search", [handler]);
  45         },
  46         flushCache: function() {
  47                 return this.trigger("flushCache");
  48         },
  49         setOptions: function(options){
  50                 return this.trigger("setOptions", [options]);
  51         },
  52         unautocomplete: function() {
  53                 return this.trigger("unautocomplete");
  54         }
  55 });
  56
  57 $.Autocompleter = function(input, options) {
  58
  59         var KEY = {
  60                 UP: 38,
  61                 DOWN: 40,
  62                 DEL: 46,
  63                 TAB: 9,
  64                 RETURN: 13,
  65                 ESC: 27,
  66                 COMMA: 188,
  67                 PAGEUP: 33,
  68                 PAGEDOWN: 34,
  69                 BACKSPACE: 8
  70         };
  71
  72         // Create $ object for input element
  73         var $input = $(input).attr("autocomplete", "off").addClass(options.inputClass);
  74
  75         var timeout;
  76         var previousValue = "";
  77         var cache = $.Autocompleter.Cache(options);
  78         var hasFocus = 0;
  79         var lastKeyPressCode;
  80         var config = {
  81                 mouseDownOnSelect: false
  82         };
  83         var select = $.Autocompleter.Select(options, input, selectCurrent, config);
  84
  85         var blockSubmit;
  86
  87         // prevent form submit in opera when selecting with return key
  88         $.browser.opera && $(input.form).bind("submit.autocomplete", function() {
  89                 if (blockSubmit) {
  90                         blockSubmit = false;
  91                         return false;
  92                 }
  93         });
  94
  95         // only opera doesn't trigger keydown multiple times while pressed, others don't work with keypress at all
  96         $input.bind(($.browser.opera ? "keypress" : "keydown") + ".autocomplete", function(event) {
  97                 // a keypress means the input has focus
  98                 // avoids issue where input had focus before the autocomplete was applied
  99                 hasFocus = 1;
 100                 // track last key pressed
 101                 lastKeyPressCode = event.keyCode;
 102                 switch(event.keyCode) {
 103
 104                         case KEY.UP:
 105                                 event.preventDefault();
 106                                 if ( select.visible() ) {
 107                                         select.prev();
 108                                 } else {
 109                                         onChange(0, true);
 110                                 }
 111                                 break;
 112
 113                         case KEY.DOWN:
 114                                 event.preventDefault();
 115                                 if ( select.visible() ) {
 116                                         select.next();
 117                                 } else {
 118                                         onChange(0, true);
 119                                 }
 120                                 break;
 121
 122                         case KEY.PAGEUP:
 123                                 event.preventDefault();
 124                                 if ( select.visible() ) {
 125                                         select.pageUp();
 126                                 } else {
 127                                         onChange(0, true);
 128                                 }
 129                                 break;
 130
 131                         case KEY.PAGEDOWN:
 132                                 event.preventDefault();
 133                                 if ( select.visible() ) {
 134                                         select.pageDown();
 135                                 } else {
 136                                         onChange(0, true);
 137                                 }
 138                                 break;
 139
 140                         // matches also semicolon
 141                         case options.multiple && $.trim(options.multipleSeparator) == "," && KEY.COMMA:
 142                         case KEY.TAB:
 143                         case KEY.RETURN:
 144                                 if( selectCurrent() ) {
 145                                         // stop default to prevent a form submit, Opera needs special handling
 146                                         event.preventDefault();
 147                                         blockSubmit = true;
 148                                         return false;
 149                                 }
 150                                 break;
 151
 152                         case KEY.ESC:
 153                                 select.hide();
 154                                 break;
 155
 156                         default:
 157                                 clearTimeout(timeout);
 158                                 timeout = setTimeout(onChange, options.delay);
 159                                 break;
 160                 }
 161         }).focus(function(){
 162                 // track whether the field has focus, we shouldn't process any
 163                 // results if the field no longer has focus
 164                 hasFocus++;
 165         }).blur(function() {
 166                 hasFocus = 0;
 167                 if (!config.mouseDownOnSelect) {
 168                         hideResults();
 169                 }
 170         }).click(function() {
 171                 // show select when clicking in a focused field
 172                 if ( hasFocus++ > 1 && !select.visible() ) {
 173                         onChange(0, true);
 174                 }
 175         }).bind("search", function() {
 176                 // TODO why not just specifying both arguments?
 177                 var fn = (arguments.length > 1) ? arguments[1] : null;
 178                 function findValueCallback(q, data) {
 179                         var result;
 180                         if( data && data.length ) {
 181                                 for (var i=0; i < data.length; i++) {
 182                                         if( data[i].result.toLowerCase() == q.toLowerCase() ) {
 183                                                 result = data[i];
 184                                                 break;
 185                                         }
 186                                 }
 187                         }
 188                         if( typeof fn == "function" ) fn(result);
 189                         else $input.trigger("result", result && [result.data, result.value]);
 190                 }
 191                 $.each(trimWords($input.val()), function(i, value) {
 192                         request(value, findValueCallback, findValueCallback);
 193                 });
 194         }).bind("flushCache", function() {
 195                 cache.flush();
 196         }).bind("setOptions", function() {
 197                 $.extend(options, arguments[1]);
 198                 // if we've updated the data, repopulate
 199                 if ( "data" in arguments[1] )
 200                         cache.populate();
 201         }).bind("unautocomplete", function() {
 202                 select.unbind();
 203                 $input.unbind();
 204                 $(input.form).unbind(".autocomplete");
 205         });
 206
 207
 208         function selectCurrent() {
 209                 var selected = select.selected();
 210                 if( !selected )
 211                         return false;
 212
 213                 var v = selected.result;
 214                 previousValue = v;
 215
 216                 if ( options.multiple ) {
 217                         var words = trimWords($input.val());
 218                         if ( words.length > 1 ) {
 219                                 var seperator = options.multipleSeparator.length;
 220                                 var cursorAt = $(input).selection().start;
 221                                 var wordAt, progress = 0;
 222                                 $.each(words, function(i, word) {
 223                                         progress += word.length;
 224                                         if (cursorAt <= progress) {
 225                                                 wordAt = i;
 226                                                 return false;
 227                                         }
 228                                         progress += seperator;
 229                                 });
 230                                 words[wordAt] = v;
 231                                 // TODO this should set the cursor to the right position, but it gets overriden somewhere
 232                                 //$.Autocompleter.Selection(input, progress + seperator, progress + seperator);
 233                                 v = words.join( options.multipleSeparator );
 234                         }
 235                         v += options.multipleSeparator;
 236                 }
 237
 238                 $input.val(v);
 239                 hideResultsNow();
 240                 $input.trigger("result", [selected.data, selected.value]);
 241                 return true;
 242         }
 243
 244         function onChange(crap, skipPrevCheck) {
 245                 if( lastKeyPressCode == KEY.DEL ) {
 246                         select.hide();
 247                         return;
 248                 }
 249
 250                 var currentValue = $input.val();
 251
 252                 if ( !skipPrevCheck && currentValue == previousValue )
 253                         return;
 254
 255                 previousValue = currentValue;
 256
 257                 currentValue = lastWord(currentValue);
 258                 if ( currentValue.length >= options.minChars) {
 259                         $input.addClass(options.loadingClass);
 260                         if (!options.matchCase)
 261                                 currentValue = currentValue.toLowerCase();
 262                         request(currentValue, receiveData, hideResultsNow);
 263                 } else {
 264                         stopLoading();
 265                         select.hide();
 266                 }
 267         };
 268
 269         function trimWords(value) {
 270                 if (!value)
 271                         return [""];
 272                 if (!options.multiple)
 273                         return [$.trim(value)];
 274                 return $.map(value.split(options.multipleSeparator), function(word) {
 275                         return $.trim(value).length ? $.trim(word) : null;
 276                 });
 277         }
 278
 279         function lastWord(value) {
 280                 if ( !options.multiple )
 281                         return value;
 282                 var words = trimWords(value);
 283                 if (words.length == 1)
 284                         return words[0];
 285                 var cursorAt = $(input).selection().start;
 286                 if (cursorAt == value.length) {
 287                         words = trimWords(value)
 288                 } else {
 289                         words = trimWords(value.replace(value.substring(cursorAt), ""));
 290                 }
 291                 return words[words.length - 1];
 292         }
 293
 294         // fills in the input box w/the first match (assumed to be the best match)
 295         // q: the term entered
 296         // sValue: the first matching result
 297         function autoFill(q, sValue){
 298                 // autofill in the complete box w/the first match as long as the user hasn't entered in more data
 299                 // if the last user key pressed was backspace, don't autofill
 300                 if( options.autoFill && (lastWord($input.val()).toLowerCase() == q.toLowerCase()) && lastKeyPressCode != KEY.BACKSPACE ) {
 301                         // fill in the value (keep the case the user has typed)
 302                         $input.val($input.val() + sValue.substring(lastWord(previousValue).length));
 303                         // select the portion of the value not typed by the user (so the next character will erase)
 304                         $(input).selection(previousValue.length, previousValue.length + sValue.length);
 305                 }
 306         };
 307
 308         function hideResults() {
 309                 clearTimeout(timeout);
 310                 timeout = setTimeout(hideResultsNow, 200);
 311         };
 312
 313         function hideResultsNow() {
 314                 var wasVisible = select.visible();
 315                 select.hide();
 316                 clearTimeout(timeout);
 317                 stopLoading();
 318                 if (options.mustMatch) {
 319                         // call search and run callback
 320                         $input.search(
 321                                 function (result){
 322                                         // if no value found, clear the input box
 323                                         if( !result ) {
 324                                                 if (options.multiple) {
 325                                                         var words = trimWords($input.val()).slice(0, -1);
 326                                                         $input.val( words.join(options.multipleSeparator) + (words.length ? options.multipleSeparator : "") );
 327                                                 }
 328                                                 else {
 329                                                         $input.val( "" );
 330                                                         $input.trigger("result", null);
 331                                                 }
 332                                         }
 333                                 }
 334                         );
 335                 }
 336         };
 337
 338         function receiveData(q, data) {
 339                 if ( data && data.length && hasFocus ) {
 340                         stopLoading();
 341                         select.display(data, q);
 342                         autoFill(q, data[0].value);
 343                         select.show();
 344                 } else {
 345                         hideResultsNow();
 346                 }
 347         };
 348
 349         function request(term, success, failure) {
 350                 if (!options.matchCase)
 351                         term = term.toLowerCase();
 352                 var data = cache.load(term);
 353                 // recieve the cached data
 354                 if (data && data.length) {
 355                         success(term, data);
 356                 // if an AJAX url has been supplied, try loading the data now
 357                 } else if( (typeof options.url == "string") && (options.url.length > 0) ){
 358
 359                         var extraParams = {
 360                                 timestamp: +new Date()
 361                         };
 362                         $.each(options.extraParams, function(key, param) {
 363                                 extraParams[key] = typeof param == "function" ? param() : param;
 364                         });
 365
 366                         $.ajax({
 367                                 // try to leverage ajaxQueue plugin to abort previous requests
 368                                 mode: "abort",
 369                                 // limit abortion to this input
 370                                 port: "autocomplete" + input.name,
 371                                 dataType: options.dataType,
 372                                 url: options.url,
 373                                 data: $.extend({
 374                                         q: lastWord(term),
 375                                         limit: options.max
 376                                 }, extraParams),
 377                                 success: function(data) {
 378                                         var parsed = options.parse && options.parse(data) || parse(data);
 379                                         cache.add(term, parsed);
 380                                         success(term, parsed);
 381                                 }
 382                         });
 383                 } else {
 384                         // if we have a failure, we need to empty the list -- this prevents the the [TAB] key from selecting the last successful match
 385                         select.emptyList();
 386                         failure(term);
 387                 }
 388         };
 389
 390         function parse(data) {
 391                 var parsed = [];
 392                 var rows = data.split("\n");
 393                 for (var i=0; i < rows.length; i++) {
 394                         var row = $.trim(rows[i]);
 395                         if (row) {
 396                                 row = row.split("|");
 397                                 parsed[parsed.length] = {
 398                                         data: row,
 399                                         value: row[0],
 400                                         result: options.formatResult && options.formatResult(row, row[0]) || row[0]
 401                                 };
 402                         }
 403                 }
 404                 return parsed;
 405         };
 406
 407         function stopLoading() {
 408                 $input.removeClass(options.loadingClass);
 409         };
 410
 411 };
 412
 413 $.Autocompleter.defaults = {
 414         inputClass: "ac_input",
 415         resultsClass: "ac_results",
 416         loadingClass: "ac_loading",
 417         minChars: 1,
 418         delay: 400,
 419         matchCase: false,
 420         matchSubset: true,
 421         matchContains: false,
 422         cacheLength: 10,
 423         max: 100,
 424         mustMatch: false,
 425         extraParams: {},
 426         selectFirst: true,
 427         formatItem: function(row) { return row[0]; },
 428         formatMatch: null,
 429         autoFill: false,
 430         width: 0,
 431         multiple: false,
 432         multipleSeparator: ", ",
 433     regex_escape: function(term) {
 434         term = term.replace(/([\^\$\(\)\[\]\{\}\*\.\+\?\|\\])/gi, "\\$1");
 435         /* no polish diacritics; should be more locale-aware */
 436         term = term.replace(/a/g, '[aą]')
 437                 .replace(/c/g, '[cć]')
 438                 .replace(/e/g, '[eę]')
 439                 .replace(/l/g, '[lł]')
 440                 .replace(/n/g, '[nń]')
 441                 .replace(/o/g, '[oó]')
 442                 .replace(/s/g, '[sś]')
 443                 .replace(/z/g, '[zźż]');
 444         return term;
 445     },
 446         highlight: function(value, term) {
 447                 term = $.Autocompleter.defaults.regex_escape(term);
 448                 return value.replace(new RegExp("(?![^&;]+;)(?!<[^<>]*)(" + term + ")(?![^<>]*>)(?![^&;]+;)", "gi"), "<strong>$1</strong>");
 449         },
 450     scroll: true,
 451     scrollHeight: 180
 452 };
 453
 454 $.Autocompleter.Cache = function(options) {
 455
 456         var data = {};
 457         var length = 0;
 458
 459         function matchSubset(s, sub) {
 460                 if (!options.matchCase)
 461                         s = s.toLowerCase();
 462                 var i = s.indexOf(sub);
 463                 if (options.matchContains == "word"){
 464                         query = $.Autocompleter.defaults.regex_escape(sub.toLowerCase());
 465                         i = s.toLowerCase().search("\\b" + query);
 466                 }
 467                 if (i == -1) return false;
 468                 return i == 0 || options.matchContains;
 469         };
 470
 471         function add(q, value) {
 472                 if (length > options.cacheLength){
 473                         flush();
 474                 }
 475                 if (!data[q]){
 476                         length++;
 477                 }
 478                 data[q] = value;
 479         }
 480
 481         function populate(){
 482                 if( !options.data ) return false;
 483                 // track the matches
 484                 var stMatchSets = {},
 485                         nullData = 0;
 486
 487                 // no url was specified, we need to adjust the cache length to make sure it fits the local data store
 488                 if( !options.url ) options.cacheLength = 1;
 489
 490                 // track all options for minChars = 0
 491                 stMatchSets[""] = [];
 492
 493                 // loop through the array and create a lookup structure
 494                 for ( var i = 0, ol = options.data.length; i < ol; i++ ) {
 495                         var rawValue = options.data[i];
 496                         // if rawValue is a string, make an array otherwise just reference the array
 497                         rawValue = (typeof rawValue == "string") ? [rawValue] : rawValue;
 498
 499                         var value = options.formatMatch(rawValue, i+1, options.data.length);
 500                         if ( value === false )
 501                                 continue;
 502
 503                         var firstChar = value.charAt(0).toLowerCase();
 504                         // if no lookup array for this character exists, look it up now
 505                         if( !stMatchSets[firstChar] )
 506                                 stMatchSets[firstChar] = [];
 507
 508                         // if the match is a string
 509                         var row = {
 510                                 value: value,
 511                                 data: rawValue,
 512                                 result: options.formatResult && options.formatResult(rawValue) || value
 513                         };
 514
 515                         // push the current match into the set list
 516                         stMatchSets[firstChar].push(row);
 517
 518                         // keep track of minChars zero items
 519                         if ( nullData++ < options.max ) {
 520                                 stMatchSets[""].push(row);
 521                         }
 522                 };
 523
 524                 // add the data items to the cache
 525                 $.each(stMatchSets, function(i, value) {
 526                         // increase the cache size
 527                         options.cacheLength++;
 528                         // add to the cache
 529                         add(i, value);
 530                 });
 531         }
 532
 533         // populate any existing data
 534         setTimeout(populate, 25);
 535
 536         function flush(){
 537                 data = {};
 538                 length = 0;
 539         }
 540
 541         return {
 542                 flush: flush,
 543                 add: add,
 544                 populate: populate,
 545                 load: function(q) {
 546                         if (!options.cacheLength || !length)
 547                                 return null;
 548                         /*
 549                          * if dealing w/local data and matchContains than we must make sure
 550                          * to loop through all the data collections looking for matches
 551                          */
 552                         if( !options.url && options.matchContains ){
 553                                 // track all matches
 554                                 var csub = [];
 555                                 // loop through all the data grids for matches
 556                                 for( var k in data ){
 557                                         // don't search through the stMatchSets[""] (minChars: 0) cache
 558                                         // this prevents duplicates
 559                                         if( k.length > 0 ){
 560                                                 var c = data[k];
 561                                                 $.each(c, function(i, x) {
 562                                                         // if we've got a match, add it to the array
 563                                                         if (matchSubset(x.value, q)) {
 564                                                                 csub.push(x);
 565                                                         }
 566                                                 });
 567                                         }
 568                                 }
 569                                 return csub;
 570                         } else
 571                         // if the exact item exists, use it
 572                         if (data[q]){
 573                                 return data[q];
 574                         } else
 575                         if (options.matchSubset) {
 576                                 for (var i = q.length - 1; i >= options.minChars; i--) {
 577                                         var c = data[q.substr(0, i)];
 578                                         if (c) {
 579                                                 var csub = [];
 580                                                 $.each(c, function(i, x) {
 581                                                         if (matchSubset(x.value, q)) {
 582                                                                 csub[csub.length] = x;
 583                                                         }
 584                                                 });
 585                                                 return csub;
 586                                         }
 587                                 }
 588                         }
 589                         return null;
 590                 }
 591         };
 592 };
 593
 594 $.Autocompleter.Select = function (options, input, select, config) {
 595         var CLASSES = {
 596                 ACTIVE: "ac_over"
 597         };
 598
 599         var listItems,
 600                 active = -1,
 601                 data,
 602                 term = "",
 603                 needsInit = true,
 604                 element,
 605                 list;
 606
 607         // Create results
 608         function init() {
 609                 if (!needsInit)
 610                         return;
 611                 element = $("<div/>")
 612                 .hide()
 613                 .addClass(options.resultsClass)
 614                 .css("position", "absolute")
 615                 .appendTo(document.body);
 616
 617                 list = $("<ul/>").appendTo(element).mouseover( function(event) {
 618                         if(target(event).nodeName && target(event).nodeName.toUpperCase() == 'LI') {
 619                     active = $("li", list).removeClass(CLASSES.ACTIVE).index(target(event));
 620                             $(target(event)).addClass(CLASSES.ACTIVE);
 621                 }
 622                 }).click(function(event) {
 623                         $(target(event)).addClass(CLASSES.ACTIVE);
 624                         select();
 625                         // TODO provide option to avoid setting focus again after selection? useful for cleanup-on-focus
 626                         input.focus();
 627                         return false;
 628                 }).mousedown(function() {
 629                         config.mouseDownOnSelect = true;
 630                 }).mouseup(function() {
 631                         config.mouseDownOnSelect = false;
 632                 });
 633
 634                 if( options.width > 0 )
 635                         element.css("width", options.width);
 636
 637                 needsInit = false;
 638         }
 639
 640         function target(event) {
 641                 var element = event.target;
 642                 while(element && element.tagName != "LI")
 643                         element = element.parentNode;
 644                 // more fun with IE, sometimes event.target is empty, just ignore it then
 645                 if(!element)
 646                         return [];
 647                 return element;
 648         }
 649
 650         function moveSelect(step) {
 651                 listItems.slice(active, active + 1).removeClass(CLASSES.ACTIVE);
 652                 movePosition(step);
 653         var activeItem = listItems.slice(active, active + 1).addClass(CLASSES.ACTIVE);
 654         if(options.scroll) {
 655             var offset = 0;
 656             listItems.slice(0, active).each(function() {
 657                                 offset += this.offsetHeight;
 658                         });
 659             if((offset + activeItem[0].offsetHeight - list.scrollTop()) > list[0].clientHeight) {
 660                 list.scrollTop(offset + activeItem[0].offsetHeight - list.innerHeight());
 661             } else if(offset < list.scrollTop()) {
 662                 list.scrollTop(offset);
 663             }
 664         }
 665         };
 666
 667         function movePosition(step) {
 668                 active += step;
 669                 if (active < 0) {
 670                         active = listItems.size() - 1;
 671                 } else if (active >= listItems.size()) {
 672                         active = 0;
 673                 }
 674         }
 675
 676         function limitNumberOfItems(available) {
 677                 return options.max && options.max < available
 678                         ? options.max
 679                         : available;
 680         }
 681
 682         function fillList() {
 683                 list.empty();
 684                 var max = limitNumberOfItems(data.length);
 685                 for (var i=0; i < max; i++) {
 686                         if (!data[i])
 687                                 continue;
 688                         var formatted = options.formatItem(data[i].data, i+1, max, data[i].value, term);
 689                         if ( formatted === false )
 690                                 continue;
 691                         var li = $("<li/>").html( options.highlight(formatted, term) ).addClass(i%2 == 0 ? "ac_even" : "ac_odd").appendTo(list)[0];
 692                         $.data(li, "ac_data", data[i]);
 693                 }
 694                 listItems = list.find("li");
 695                 if ( options.selectFirst ) {
 696                         listItems.slice(0, 1).addClass(CLASSES.ACTIVE);
 697                         active = 0;
 698                 }
 699                 // apply bgiframe if available
 700                 if ( $.fn.bgiframe )
 701                         list.bgiframe();
 702         }
 703
 704         return {
 705                 display: function(d, q) {
 706                         init();
 707                         data = d;
 708                         term = q;
 709                         fillList();
 710                 },
 711                 next: function() {
 712                         moveSelect(1);
 713                 },
 714                 prev: function() {
 715                         moveSelect(-1);
 716                 },
 717                 pageUp: function() {
 718                         if (active != 0 && active - 8 < 0) {
 719                                 moveSelect( -active );
 720                         } else {
 721                                 moveSelect(-8);
 722                         }
 723                 },
 724                 pageDown: function() {
 725                         if (active != listItems.size() - 1 && active + 8 > listItems.size()) {
 726                                 moveSelect( listItems.size() - 1 - active );
 727                         } else {
 728                                 moveSelect(8);
 729                         }
 730                 },
 731                 hide: function() {
 732                         element && element.hide();
 733                         listItems && listItems.removeClass(CLASSES.ACTIVE);
 734                         active = -1;
 735                 },
 736                 visible : function() {
 737                         return element && element.is(":visible");
 738                 },
 739                 current: function() {
 740                         return this.visible() && (listItems.filter("." + CLASSES.ACTIVE)[0] || options.selectFirst && listItems[0]);
 741                 },
 742                 show: function() {
 743                         var offset = $(input).offset();
 744                         element.css({
 745                                 width: typeof options.width == "string" || options.width > 0 ? options.width : $(input).width(),
 746                                 top: offset.top + input.offsetHeight,
 747                                 left: offset.left
 748                         }).show();
 749             if(options.scroll) {
 750                 list.scrollTop(0);
 751                 list.css({
 752                                         maxHeight: options.scrollHeight,
 753                                         overflow: 'auto'
 754                                 });
 755
 756                 if($.browser.msie && typeof document.body.style.maxHeight === "undefined") {
 757                                         var listHeight = 0;
 758                                         listItems.each(function() {
 759                                                 listHeight += this.offsetHeight;
 760                                         });
 761                                         var scrollbarsVisible = listHeight > options.scrollHeight;
 762                     list.css('height', scrollbarsVisible ? options.scrollHeight : listHeight );
 763                                         if (!scrollbarsVisible) {
 764                                                 // IE doesn't recalculate width when scrollbar disappears
 765                                                 listItems.width( list.width() - parseInt(listItems.css("padding-left")) - parseInt(listItems.css("padding-right")) );
 766                                         }
 767                 }
 768
 769             }
 770                 },
 771                 selected: function() {
 772                         var selected = listItems && listItems.filter("." + CLASSES.ACTIVE).removeClass(CLASSES.ACTIVE);
 773                         return selected && selected.length && $.data(selected[0], "ac_data");
 774                 },
 775                 emptyList: function (){
 776                         list && list.empty();
 777                 },
 778                 unbind: function() {
 779                         element && element.remove();
 780                 }
 781         };
 782 };
 783
 784 $.fn.selection = function(start, end) {
 785         if (start !== undefined) {
 786                 return this.each(function() {
 787                         if( this.createTextRange ){
 788                                 var selRange = this.createTextRange();
 789                                 if (end === undefined || start == end) {
 790                                         selRange.move("character", start);
 791                                         selRange.select();
 792                                 } else {
 793                                         selRange.collapse(true);
 794                                         selRange.moveStart("character", start);
 795                                         selRange.moveEnd("character", end);
 796                                         selRange.select();
 797                                 }
 798                         } else if( this.setSelectionRange ){
 799                                 this.setSelectionRange(start, end);
 800                         } else if( this.selectionStart ){
 801                                 this.selectionStart = start;
 802                                 this.selectionEnd = end;
 803                         }
 804                 });
 805         }
 806         var field = this[0];
 807         if ( field.createTextRange ) {
 808                 var range = document.selection.createRange(),
 809                         orig = field.value,
 810                         teststring = "<->",
 811                         textLength = range.text.length;
 812                 range.text = teststring;
 813                 var caretAt = field.value.indexOf(teststring);
 814                 field.value = orig;
 815                 this.selection(caretAt, caretAt + textLength);
 816                 return {
 817                         start: caretAt,
 818                         end: caretAt + textLength
 819                 }
 820         } else if( field.selectionStart !== undefined ){
 821                 return {
 822                         start: field.selectionStart,
 823                         end: field.selectionEnd
 824                 }
 825         }
 826 };
 827
 828 })(jQuery);