resources/src/jquery/jquery.suggestions.js

   1 /**
   2  * This plugin provides a generic way to add suggestions to a text box.
   3  *
   4  * Set options:
   5  *
   6  *              $( '#textbox' ).suggestions( { option1: value1, option2: value2 } );
   7  *              $( '#textbox' ).suggestions( option, value );
   8  *
   9  * Get option:
  10  *
  11  *              value = $( '#textbox' ).suggestions( option );
  12  *
  13  * Initialize:
  14  *
  15  *              $( '#textbox' ).suggestions();
  16  *
  17  * Uses jQuery.suggestions singleton internally.
  18  *
  19  * @class jQuery.plugin.suggestions
  20  */
  21
  22 /**
  23  * @method suggestions
  24  * @chainable
  25  * @return {jQuery}
  26  *
  27  * @param {Object} options
  28  *
  29  * @param {Function} [options.fetch] Callback that should fetch suggestions and set the suggestions
  30  *  property. Called in context of the text box.
  31  * @param {string} options.fetch.query
  32  * @param {Function} options.fetch.response Callback to receive the suggestions with
  33  * @param {Array} options.fetch.response.suggestions
  34  * @param {number} options.fetch.maxRows
  35  *
  36  * @param {Function} [options.cancel] Callback function to call when any pending asynchronous
  37  *  suggestions fetches. Called in context of the text box.
  38  *
  39  * @param {Object} [options.special] Set of callbacks for rendering and selecting.
  40  *
  41  * @param {Function} options.special.render Called in context of the suggestions-special element.
  42  * @param {string} options.special.render.query
  43  * @param {Object} options.special.render.context
  44  *
  45  * @param {Function} options.special.select Called in context of the suggestions-result-current element.
  46  * @param {jQuery} options.special.select.$textbox
  47  *
  48  * @param {Object} [options.result] Set of callbacks for rendering and selecting
  49  *
  50  * @param {Function} options.result.render Called in context of the suggestions-result element.
  51  * @param {string} options.result.render.suggestion
  52  * @param {Object} options.result.render.context
  53  *
  54  * @param {Function} options.result.select Called in context of the suggestions-result-current element.
  55  * @param {jQuery} options.result.select.$textbox
  56  *
  57  * @param {Object} [options.update] Set of callbacks for listening to a change in the text input.
  58  *
  59  * @param {Function} options.update.before Called right after the user changes the textbox text.
  60  * @param {Function} options.update.after Called after results are updated either from the cache or
  61  * the API as a result of the user input.
  62  *
  63  * @param {jQuery} [options.$region=this] The element to place the suggestions below and match width of.
  64  *
  65  * @param {string[]} [options.suggestions] Array of suggestions to display.
  66  *
  67  * @param {number} [options.maxRows=10] Maximum number of suggestions to display at one time.
  68  *  Must be between 1 and 100.
  69  *
  70  * @param {number} [options.delay=120] Number of milliseconds to wait for the user to stop typing.
  71  *  Must be between 0 and 1200.
  72  *
  73  * @param {boolean} [options.cache=false] Whether to cache results from a fetch.
  74  *
  75  * @param {number} [options.cacheMaxAge=60000] Number of milliseconds to cache results from a fetch.
  76  *  Must be higher than 1. Defaults to 1 minute.
  77  *
  78  * @param {boolean} [options.submitOnClick=false] Whether to submit the form containing the textbox
  79  *  when a suggestion is clicked.
  80  *
  81  * @param {number} [options.maxExpandFactor=3] Maximum suggestions box width relative to the textbox
  82  *  width. If set to e.g. 2, the suggestions box will never be grown beyond 2 times the width of
  83  *  the textbox. Must be higher than 1.
  84  *
  85  * @param {string} [options.expandFrom=auto] Which direction to offset the suggestion box from.
  86  *  Values 'start' and 'end' translate to left and right respectively depending on the directionality
  87  *   of the current document, according to `$( 'html' ).css( 'direction' )`.
  88  *   Valid values: "left", "right", "start", "end", and "auto".
  89  *
  90  * @param {boolean} [options.positionFromLeft] Sets `expandFrom=left`, for backwards
  91  *  compatibility.
  92  *
  93  * @param {boolean} [options.highlightInput=false] Whether to highlight matched portions of the
  94  *  input or not.
  95  */
  96
  97 ( function ( $, mw ) {
  98
  99         var hasOwn = Object.hasOwnProperty;
 100
 101         /**
 102          * Used by jQuery.plugin.suggestions.
 103          *
 104          * @class jQuery.suggestions
 105          * @singleton
 106          * @private
 107          */
 108         $.suggestions = {
 109                 /**
 110                  * Cancel any delayed maybeFetch() call and callback the context so
 111                  * they can cancel any async fetching if they use AJAX or something.
 112                  *
 113                  * @param {Object} context
 114                  */
 115                 cancel: function ( context ) {
 116                         if ( context.data.timerID !== null ) {
 117                                 clearTimeout( context.data.timerID );
 118                         }
 119                         if ( $.isFunction( context.config.cancel ) ) {
 120                                 context.config.cancel.call( context.data.$textbox );
 121                         }
 122                 },
 123
 124                 /**
 125                  * Hide the element with suggestions and clean up some state.
 126                  *
 127                  * @param {Object} context
 128                  */
 129                 hide: function ( context ) {
 130                         // Remove any highlights, including on "special" items
 131                         context.data.$container.find( '.suggestions-result-current' ).removeClass( 'suggestions-result-current' );
 132                         // Hide the container
 133                         context.data.$container.hide();
 134                 },
 135
 136                 /**
 137                  * Restore the text the user originally typed in the textbox, before it
 138                  * was overwritten by highlight(). This restores the value the currently
 139                  * displayed suggestions are based on, rather than the value just before
 140                  * highlight() overwrote it; the former is arguably slightly more sensible.
 141                  *
 142                  * @param {Object} context
 143                  */
 144                 restore: function ( context ) {
 145                         context.data.$textbox.val( context.data.prevText );
 146                 },
 147
 148                 /**
 149                  * Ask the user-specified callback for new suggestions. Any previous delayed
 150                  * call to this function still pending will be canceled. If the value in the
 151                  * textbox is empty or hasn't changed since the last time suggestions were fetched,
 152                  * this function does nothing.
 153                  *
 154                  * @param {Object} context
 155                  * @param {boolean} delayed Whether or not to delay this by the currently configured amount of time
 156                  */
 157                 update: function ( context, delayed ) {
 158                         function maybeFetch() {
 159                                 var val = context.data.$textbox.val(),
 160                                         cache = context.data.cache,
 161                                         cacheHit;
 162
 163                                 if ( typeof context.config.update.before === 'function' ) {
 164                                         context.config.update.before.call( context.data.$textbox );
 165                                 }
 166
 167                                 // Only fetch if the value in the textbox changed and is not empty, or if the results were hidden
 168                                 // if the textbox is empty then clear the result div, but leave other settings intouched
 169                                 if ( val.length === 0 ) {
 170                                         $.suggestions.hide( context );
 171                                         context.data.prevText = '';
 172                                 } else if (
 173                                         val !== context.data.prevText ||
 174                                         !context.data.$container.is( ':visible' )
 175                                 ) {
 176                                         context.data.prevText = val;
 177                                         // Try cache first
 178                                         if ( context.config.cache && hasOwn.call( cache, val ) ) {
 179                                                 if ( mw.now() - cache[ val ].timestamp < context.config.cacheMaxAge ) {
 180                                                         context.data.$textbox.suggestions( 'suggestions', cache[ val ].suggestions );
 181                                                         if ( typeof context.config.update.after === 'function' ) {
 182                                                                 context.config.update.after.call( context.data.$textbox, cache[ val ].metadata );
 183                                                         }
 184                                                         cacheHit = true;
 185                                                 } else {
 186                                                         // Cache expired
 187                                                         delete cache[ val ];
 188                                                 }
 189                                         }
 190                                         if ( !cacheHit && typeof context.config.fetch === 'function' ) {
 191                                                 context.config.fetch.call(
 192                                                         context.data.$textbox,
 193                                                         val,
 194                                                         function ( suggestions, metadata ) {
 195                                                                 suggestions = suggestions.slice( 0, context.config.maxRows );
 196                                                                 context.data.$textbox.suggestions( 'suggestions', suggestions );
 197                                                                 if ( typeof context.config.update.after === 'function' ) {
 198                                                                         context.config.update.after.call( context.data.$textbox, metadata );
 199                                                                 }
 200                                                                 if ( context.config.cache ) {
 201                                                                         cache[ val ] = {
 202                                                                                 suggestions: suggestions,
 203                                                                                 metadata: metadata,
 204                                                                                 timestamp: mw.now()
 205                                                                         };
 206                                                                 }
 207                                                         },
 208                                                         context.config.maxRows
 209                                                 );
 210                                         }
 211                                 }
 212
 213                                 // Always update special rendering
 214                                 $.suggestions.special( context );
 215                         }
 216
 217                         // Cancels any delayed maybeFetch call, and invokes context.config.cancel.
 218                         $.suggestions.cancel( context );
 219
 220                         if ( delayed ) {
 221                                 // To avoid many started/aborted requests while typing, we're gonna take a short
 222                                 // break before trying to fetch data.
 223                                 context.data.timerID = setTimeout( maybeFetch, context.config.delay );
 224                         } else {
 225                                 maybeFetch();
 226                         }
 227                 },
 228
 229                 /**
 230                  * @param {Object} context
 231                 */
 232                 special: function ( context ) {
 233                         // Allow custom rendering - but otherwise don't do any rendering
 234                         if ( typeof context.config.special.render === 'function' ) {
 235                                 // Wait for the browser to update the value
 236                                 setTimeout( function () {
 237                                         // Render special
 238                                         var $special = context.data.$container.find( '.suggestions-special' );
 239                                         context.config.special.render.call( $special, context.data.$textbox.val(), context );
 240                                 }, 1 );
 241                         }
 242                 },
 243
 244                 /**
 245                  * Sets the value of a property, and updates the widget accordingly
 246                  *
 247                  * @param {Object} context
 248                  * @param {string} property Name of property
 249                  * @param {Mixed} value Value to set property with
 250                  */
 251                 configure: function ( context, property, value ) {
 252                         var newCSS,
 253                                 $result, $results, $spanForWidth, childrenWidth,
 254                                 i, expWidth, maxWidth, text;
 255
 256                         // Validate creation using fallback values
 257                         switch ( property ) {
 258                                 case 'fetch':
 259                                 case 'cancel':
 260                                 case 'special':
 261                                 case 'result':
 262                                 case 'update':
 263                                 case '$region':
 264                                 case 'expandFrom':
 265                                         context.config[ property ] = value;
 266                                         break;
 267                                 case 'suggestions':
 268                                         context.config[ property ] = value;
 269                                         // Update suggestions
 270                                         if ( context.data !== undefined ) {
 271                                                 if ( context.data.$textbox.val().length === 0 ) {
 272                                                         // Hide the div when no suggestion exist
 273                                                         $.suggestions.hide( context );
 274                                                 } else {
 275                                                         // Rebuild the suggestions list
 276                                                         context.data.$container.show();
 277                                                         // Update the size and position of the list
 278                                                         newCSS = {
 279                                                                 top: context.config.$region.offset().top + context.config.$region.outerHeight(),
 280                                                                 bottom: 'auto',
 281                                                                 width: context.config.$region.outerWidth(),
 282                                                                 height: 'auto'
 283                                                         };
 284
 285                                                         // Process expandFrom, after this it is set to left or right.
 286                                                         context.config.expandFrom = ( function ( expandFrom ) {
 287                                                                 var regionWidth, docWidth, regionCenter, docCenter,
 288                                                                         docDir = $( document.documentElement ).css( 'direction' ),
 289                                                                         $region = context.config.$region;
 290
 291                                                                 // Backwards compatible
 292                                                                 if ( context.config.positionFromLeft ) {
 293                                                                         expandFrom = 'left';
 294
 295                                                                 // Catch invalid values, default to 'auto'
 296                                                                 } else if ( $.inArray( expandFrom, [ 'left', 'right', 'start', 'end', 'auto' ] ) === -1 ) {
 297                                                                         expandFrom = 'auto';
 298                                                                 }
 299
 300                                                                 if ( expandFrom === 'auto' ) {
 301                                                                         if ( $region.data( 'searchsuggest-expand-dir' ) ) {
 302                                                                                 // If the markup explicitly contains a direction, use it.
 303                                                                                 expandFrom = $region.data( 'searchsuggest-expand-dir' );
 304                                                                         } else {
 305                                                                                 regionWidth = $region.outerWidth();
 306                                                                                 docWidth = $( document ).width();
 307                                                                                 if ( regionWidth > ( 0.85 * docWidth ) ) {
 308                                                                                         // If the input size takes up more than 85% of the document horizontally
 309                                                                                         // expand the suggestions to the writing direction's native end.
 310                                                                                         expandFrom = 'start';
 311                                                                                 } else {
 312                                                                                         // Calculate the center points of the input and document
 313                                                                                         regionCenter = $region.offset().left + regionWidth / 2;
 314                                                                                         docCenter = docWidth / 2;
 315                                                                                         if ( Math.abs( regionCenter - docCenter ) < ( 0.10 * docCenter ) ) {
 316                                                                                                 // If the input's center is within 10% of the document center
 317                                                                                                 // use the writing direction's native end.
 318                                                                                                 expandFrom = 'start';
 319                                                                                         } else {
 320                                                                                                 // Otherwise expand the input from the closest side of the page,
 321                                                                                                 // towards the side of the page with the most free open space
 322                                                                                                 expandFrom = regionCenter > docCenter ? 'right' : 'left';
 323                                                                                         }
 324                                                                                 }
 325                                                                         }
 326                                                                 }
 327
 328                                                                 if ( expandFrom === 'start' ) {
 329                                                                         expandFrom = docDir === 'rtl' ? 'right' : 'left';
 330
 331                                                                 } else if ( expandFrom === 'end' ) {
 332                                                                         expandFrom = docDir === 'rtl' ? 'left' : 'right';
 333                                                                 }
 334
 335                                                                 return expandFrom;
 336
 337                                                         }( context.config.expandFrom ) );
 338
 339                                                         if ( context.config.expandFrom === 'left' ) {
 340                                                                 // Expand from left
 341                                                                 newCSS.left = context.config.$region.offset().left;
 342                                                                 newCSS.right = 'auto';
 343                                                         } else {
 344                                                                 // Expand from right
 345                                                                 newCSS.left = 'auto';
 346                                                                 newCSS.right = $( 'body' ).width() - ( context.config.$region.offset().left + context.config.$region.outerWidth() );
 347                                                         }
 348
 349                                                         context.data.$container.css( newCSS );
 350                                                         $results = context.data.$container.children( '.suggestions-results' );
 351                                                         $results.empty();
 352                                                         expWidth = -1;
 353                                                         for ( i = 0; i < context.config.suggestions.length; i++ ) {
 354                                                                 text = context.config.suggestions[ i ];
 355                                                                 $result = $( '<div>' )
 356                                                                         .addClass( 'suggestions-result' )
 357                                                                         .attr( 'rel', i )
 358                                                                         .data( 'text', context.config.suggestions[ i ] )
 359                                                                         .mousemove( function () {
 360                                                                                 context.data.selectedWithMouse = true;
 361                                                                                 $.suggestions.highlight(
 362                                                                                         context,
 363                                                                                         $( this ).closest( '.suggestions-results .suggestions-result' ),
 364                                                                                         false
 365                                                                                 );
 366                                                                         } )
 367                                                                         .appendTo( $results );
 368                                                                 // Allow custom rendering
 369                                                                 if ( typeof context.config.result.render === 'function' ) {
 370                                                                         context.config.result.render.call( $result, context.config.suggestions[ i ], context );
 371                                                                 } else {
 372                                                                         $result.text( text );
 373                                                                 }
 374
 375                                                                 if ( context.config.highlightInput ) {
 376                                                                         $result.highlightText( context.data.prevText, { method: 'prefixHighlight' } );
 377                                                                 }
 378
 379                                                                 // Widen results box if needed (new width is only calculated here, applied later).
 380
 381                                                                 // The monstrosity below accomplishes two things:
 382                                                                 // * Wraps the text contents in a DOM element, so that we can know its width. There is
 383                                                                 //   no way to directly access the width of a text node, and we can't use the parent
 384                                                                 //   node width as it has text-overflow: ellipsis; and overflow: hidden; applied to
 385                                                                 //   it, which trims it to a smaller width.
 386                                                                 // * Temporarily applies position: absolute; to the wrapper to pull it out of normal
 387                                                                 //   document flow. Otherwise the CSS text-overflow: ellipsis; and overflow: hidden;
 388                                                                 //   rules would cause some browsers (at least all versions of IE from 6 to 11) to
 389                                                                 //   still report the "trimmed" width. This should not be done in regular CSS
 390                                                                 //   stylesheets as we don't want this rule to apply to other <span> elements, like
 391                                                                 //   the ones generated by jquery.highlightText.
 392                                                                 $spanForWidth = $result.wrapInner( '<span>' ).children();
 393                                                                 childrenWidth = $spanForWidth.css( 'position', 'absolute' ).outerWidth();
 394                                                                 $spanForWidth.contents().unwrap();
 395
 396                                                                 if ( childrenWidth > $result.width() && childrenWidth > expWidth ) {
 397                                                                         // factor in any padding, margin, or border space on the parent
 398                                                                         expWidth = childrenWidth + ( context.data.$container.width() - $result.width() );
 399                                                                 }
 400                                                         }
 401
 402                                                         // Apply new width for results box, if any
 403                                                         if ( expWidth > context.data.$container.width() ) {
 404                                                                 maxWidth = context.config.maxExpandFactor * context.data.$textbox.width();
 405                                                                 context.data.$container.width( Math.min( expWidth, maxWidth ) );
 406                                                         }
 407                                                 }
 408                                         }
 409                                         break;
 410                                 case 'maxRows':
 411                                         context.config[ property ] = Math.max( 1, Math.min( 100, value ) );
 412                                         break;
 413                                 case 'delay':
 414                                         context.config[ property ] = Math.max( 0, Math.min( 1200, value ) );
 415                                         break;
 416                                 case 'cacheMaxAge':
 417                                         context.config[ property ] = Math.max( 1, value );
 418                                         break;
 419                                 case 'maxExpandFactor':
 420                                         context.config[ property ] = Math.max( 1, value );
 421                                         break;
 422                                 case 'cache':
 423                                 case 'submitOnClick':
 424                                 case 'positionFromLeft':
 425                                 case 'highlightInput':
 426                                         context.config[ property ] = !!value;
 427                                         break;
 428                         }
 429                 },
 430
 431                 /**
 432                  * Highlight a result in the results table
 433                  *
 434                  * @param {Object} context
 435                  * @param {jQuery|string} result `<tr>` to highlight, or 'prev' or 'next'
 436                  * @param {boolean} updateTextbox If true, put the suggestion in the textbox
 437                  */
 438                 highlight: function ( context, result, updateTextbox ) {
 439                         var selected = context.data.$container.find( '.suggestions-result-current' );
 440                         if ( !result.get || selected.get( 0 ) !== result.get( 0 ) ) {
 441                                 if ( result === 'prev' ) {
 442                                         if ( selected.hasClass( 'suggestions-special' ) ) {
 443                                                 result = context.data.$container.find( '.suggestions-result:last' );
 444                                         } else {
 445                                                 result = selected.prev();
 446                                                 if ( !( result.length && result.hasClass( 'suggestions-result' ) ) ) {
 447                                                         // there is something in the DOM between selected element and the wrapper, bypass it
 448                                                         result = selected.parents( '.suggestions-results > *' ).prev().find( '.suggestions-result' ).eq( 0 );
 449                                                 }
 450
 451                                                 if ( selected.length === 0 ) {
 452                                                         // we are at the beginning, so lets jump to the last item
 453                                                         if ( context.data.$container.find( '.suggestions-special' ).html() !== '' ) {
 454                                                                 result = context.data.$container.find( '.suggestions-special' );
 455                                                         } else {
 456                                                                 result = context.data.$container.find( '.suggestions-results .suggestions-result:last' );
 457                                                         }
 458                                                 }
 459                                         }
 460                                 } else if ( result === 'next' ) {
 461                                         if ( selected.length === 0 ) {
 462                                                 // No item selected, go to the first one
 463                                                 result = context.data.$container.find( '.suggestions-results .suggestions-result:first' );
 464                                                 if ( result.length === 0 && context.data.$container.find( '.suggestions-special' ).html() !== '' ) {
 465                                                         // No suggestion exists, go to the special one directly
 466                                                         result = context.data.$container.find( '.suggestions-special' );
 467                                                 }
 468                                         } else {
 469                                                 result = selected.next();
 470                                                 if ( !( result.length && result.hasClass( 'suggestions-result' ) ) ) {
 471                                                         // there is something in the DOM between selected element and the wrapper, bypass it
 472                                                         result = selected.parents( '.suggestions-results > *' ).next().find( '.suggestions-result' ).eq( 0 );
 473                                                 }
 474
 475                                                 if ( selected.hasClass( 'suggestions-special' ) ) {
 476                                                         result = $( [] );
 477                                                 } else if (
 478                                                         result.length === 0 &&
 479                                                         context.data.$container.find( '.suggestions-special' ).html() !== ''
 480                                                 ) {
 481                                                         // We were at the last item, jump to the specials!
 482                                                         result = context.data.$container.find( '.suggestions-special' );
 483                                                 }
 484                                         }
 485                                 }
 486                                 selected.removeClass( 'suggestions-result-current' );
 487                                 result.addClass( 'suggestions-result-current' );
 488                         }
 489                         if ( updateTextbox ) {
 490                                 if ( result.length === 0 || result.is( '.suggestions-special' ) ) {
 491                                         $.suggestions.restore( context );
 492                                 } else {
 493                                         context.data.$textbox.val( result.data( 'text' ) );
 494                                         // .val() doesn't call any event handlers, so
 495                                         // let the world know what happened
 496                                         context.data.$textbox.change();
 497                                 }
 498                                 context.data.$textbox.trigger( 'change' );
 499                         }
 500                 },
 501
 502                 /**
 503                  * Respond to keypress event
 504                  *
 505                  * @param {jQuery.Event} e
 506                  * @param {Object} context
 507                  * @param {number} key Code of key pressed
 508                  */
 509                 keypress: function ( e, context, key ) {
 510                         var selected,
 511                                 wasVisible = context.data.$container.is( ':visible' ),
 512                                 preventDefault = false;
 513
 514                         switch ( key ) {
 515                                 // Arrow down
 516                                 case 40:
 517                                         if ( wasVisible ) {
 518                                                 $.suggestions.highlight( context, 'next', true );
 519                                                 context.data.selectedWithMouse = false;
 520                                         } else {
 521                                                 $.suggestions.update( context, false );
 522                                         }
 523                                         preventDefault = true;
 524                                         break;
 525                                 // Arrow up
 526                                 case 38:
 527                                         if ( wasVisible ) {
 528                                                 $.suggestions.highlight( context, 'prev', true );
 529                                                 context.data.selectedWithMouse = false;
 530                                         }
 531                                         preventDefault = wasVisible;
 532                                         break;
 533                                 // Escape
 534                                 case 27:
 535                                         $.suggestions.hide( context );
 536                                         $.suggestions.restore( context );
 537                                         $.suggestions.cancel( context );
 538                                         context.data.$textbox.trigger( 'change' );
 539                                         preventDefault = wasVisible;
 540                                         break;
 541                                 // Enter
 542                                 case 13:
 543                                         preventDefault = wasVisible;
 544                                         selected = context.data.$container.find( '.suggestions-result-current' );
 545                                         $.suggestions.hide( context );
 546                                         if ( selected.length === 0 || context.data.selectedWithMouse ) {
 547                                                 // If nothing is selected or if something was selected with the mouse
 548                                                 // cancel any current requests and allow the form to be submitted
 549                                                 // (simply don't prevent default behavior).
 550                                                 $.suggestions.cancel( context );
 551                                                 preventDefault = false;
 552                                         } else if ( selected.is( '.suggestions-special' ) ) {
 553                                                 if ( typeof context.config.special.select === 'function' ) {
 554                                                         // Allow the callback to decide whether to prevent default or not
 555                                                         if ( context.config.special.select.call( selected, context.data.$textbox, 'keyboard' ) === true ) {
 556                                                                 preventDefault = false;
 557                                                         }
 558                                                 }
 559                                         } else {
 560                                                 if ( typeof context.config.result.select === 'function' ) {
 561                                                         // Allow the callback to decide whether to prevent default or not
 562                                                         if ( context.config.result.select.call( selected, context.data.$textbox, 'keyboard' ) === true ) {
 563                                                                 preventDefault = false;
 564                                                         }
 565                                                 }
 566                                         }
 567                                         break;
 568                                 default:
 569                                         $.suggestions.update( context, true );
 570                                         break;
 571                         }
 572                         if ( preventDefault ) {
 573                                 e.preventDefault();
 574                                 e.stopPropagation();
 575                         }
 576                 }
 577         };
 578
 579         // See file header for method documentation
 580         $.fn.suggestions = function () {
 581
 582                 // Multi-context fields
 583                 var returnValue,
 584                         args = arguments;
 585
 586                 $( this ).each( function () {
 587                         var context, key;
 588
 589                         /* Construction and Loading */
 590
 591                         context = $( this ).data( 'suggestions-context' );
 592                         if ( context === undefined || context === null ) {
 593                                 context = {
 594                                         config: {
 595                                                 fetch: function () {},
 596                                                 cancel: function () {},
 597                                                 special: {},
 598                                                 result: {},
 599                                                 update: {},
 600                                                 $region: $( this ),
 601                                                 suggestions: [],
 602                                                 maxRows: 10,
 603                                                 delay: 120,
 604                                                 cache: false,
 605                                                 cacheMaxAge: 60000,
 606                                                 submitOnClick: false,
 607                                                 maxExpandFactor: 3,
 608                                                 expandFrom: 'auto',
 609                                                 highlightInput: false
 610                                         }
 611                                 };
 612                         }
 613
 614                         /* API */
 615
 616                         // Handle various calling styles
 617                         if ( args.length > 0 ) {
 618                                 if ( typeof args[ 0 ] === 'object' ) {
 619                                         // Apply set of properties
 620                                         for ( key in args[ 0 ] ) {
 621                                                 $.suggestions.configure( context, key, args[ 0 ][ key ] );
 622                                         }
 623                                 } else if ( typeof args[ 0 ] === 'string' ) {
 624                                         if ( args.length > 1 ) {
 625                                                 // Set property values
 626                                                 $.suggestions.configure( context, args[ 0 ], args[ 1 ] );
 627                                         } else if ( returnValue === null || returnValue === undefined ) {
 628                                                 // Get property values, but don't give access to internal data - returns only the first
 629                                                 returnValue = ( args[ 0 ] in context.config ? undefined : context.config[ args[ 0 ] ] );
 630                                         }
 631                                 }
 632                         }
 633
 634                         /* Initialization */
 635
 636                         if ( context.data === undefined ) {
 637                                 context.data = {
 638                                         // ID of running timer
 639                                         timerID: null,
 640
 641                                         // Text in textbox when suggestions were last fetched
 642                                         prevText: null,
 643
 644                                         // Cache of fetched suggestions
 645                                         cache: {},
 646
 647                                         // Number of results visible without scrolling
 648                                         visibleResults: 0,
 649
 650                                         // Suggestion the last mousedown event occurred on
 651                                         mouseDownOn: $( [] ),
 652                                         $textbox: $( this ),
 653                                         selectedWithMouse: false
 654                                 };
 655
 656                                 context.data.$container = $( '<div>' )
 657                                         .css( 'display', 'none' )
 658                                         .addClass( 'suggestions' )
 659                                         .append(
 660                                                 $( '<div>' ).addClass( 'suggestions-results' )
 661                                                         // Can't use click() because the container div is hidden when the
 662                                                         // textbox loses focus. Instead, listen for a mousedown followed
 663                                                         // by a mouseup on the same div.
 664                                                         .mousedown( function ( e ) {
 665                                                                 context.data.mouseDownOn = $( e.target ).closest( '.suggestions-results .suggestions-result' );
 666                                                         } )
 667                                                         .mouseup( function ( e ) {
 668                                                                 var $result = $( e.target ).closest( '.suggestions-results .suggestions-result' ),
 669                                                                         $other = context.data.mouseDownOn;
 670
 671                                                                 context.data.mouseDownOn = $( [] );
 672                                                                 if ( $result.get( 0 ) !== $other.get( 0 ) ) {
 673                                                                         return;
 674                                                                 }
 675                                                                 $.suggestions.highlight( context, $result, true );
 676                                                                 if ( typeof context.config.result.select === 'function' ) {
 677                                                                         context.config.result.select.call( $result, context.data.$textbox, 'mouse' );
 678                                                                 }
 679                                                                 // Don't interfere with special clicks (e.g. to open in new tab)
 680                                                                 if ( !( e.which !== 1 || e.altKey || e.ctrlKey || e.shiftKey || e.metaKey ) ) {
 681                                                                         // This will hide the link we're just clicking on, which causes problems
 682                                                                         // when done synchronously in at least Firefox 3.6 (T64858).
 683                                                                         setTimeout( function () {
 684                                                                                 $.suggestions.hide( context );
 685                                                                         }, 0 );
 686                                                                 }
 687                                                                 // Always bring focus to the textbox, as that's probably where the user expects it
 688                                                                 // if they were just typing.
 689                                                                 context.data.$textbox.focus();
 690                                                         } )
 691                                         )
 692                                         .append(
 693                                                 $( '<div>' ).addClass( 'suggestions-special' )
 694                                                         // Can't use click() because the container div is hidden when the
 695                                                         // textbox loses focus. Instead, listen for a mousedown followed
 696                                                         // by a mouseup on the same div.
 697                                                         .mousedown( function ( e ) {
 698                                                                 context.data.mouseDownOn = $( e.target ).closest( '.suggestions-special' );
 699                                                         } )
 700                                                         .mouseup( function ( e ) {
 701                                                                 var $special = $( e.target ).closest( '.suggestions-special' ),
 702                                                                         $other = context.data.mouseDownOn;
 703
 704                                                                 context.data.mouseDownOn = $( [] );
 705                                                                 if ( $special.get( 0 ) !== $other.get( 0 ) ) {
 706                                                                         return;
 707                                                                 }
 708                                                                 if ( typeof context.config.special.select === 'function' ) {
 709                                                                         context.config.special.select.call( $special, context.data.$textbox, 'mouse' );
 710                                                                 }
 711                                                                 // Don't interfere with special clicks (e.g. to open in new tab)
 712                                                                 if ( !( e.which !== 1 || e.altKey || e.ctrlKey || e.shiftKey || e.metaKey ) ) {
 713                                                                         // This will hide the link we're just clicking on, which causes problems
 714                                                                         // when done synchronously in at least Firefox 3.6 (T64858).
 715                                                                         setTimeout( function () {
 716                                                                                 $.suggestions.hide( context );
 717                                                                         }, 0 );
 718                                                                 }
 719                                                                 // Always bring focus to the textbox, as that's probably where the user expects it
 720                                                                 // if they were just typing.
 721                                                                 context.data.$textbox.focus();
 722                                                         } )
 723                                                         .mousemove( function ( e ) {
 724                                                                 context.data.selectedWithMouse = true;
 725                                                                 $.suggestions.highlight(
 726                                                                         context, $( e.target ).closest( '.suggestions-special' ), false
 727                                                                 );
 728                                                         } )
 729                                         )
 730                                         .appendTo( $( 'body' ) );
 731
 732                                 $( this )
 733                                         // Stop browser autocomplete from interfering
 734                                         .attr( 'autocomplete', 'off' )
 735                                         .keydown( function ( e ) {
 736                                                 // Store key pressed to handle later
 737                                                 context.data.keypressed = e.which;
 738                                                 context.data.keypressedCount = 0;
 739                                         } )
 740                                         .keypress( function ( e ) {
 741                                                 context.data.keypressedCount++;
 742                                                 $.suggestions.keypress( e, context, context.data.keypressed );
 743                                         } )
 744                                         .keyup( function ( e ) {
 745                                                 // The keypress event is fired when a key is pressed down and that key normally
 746                                                 // produces a character value. We also want to handle some keys that don't
 747                                                 // produce a character value so we also attach to the keydown/keyup events.
 748                                                 // List of codes sourced from
 749                                                 // https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/keyCode
 750                                                 var allowed = [
 751                                                         40, // up arrow
 752                                                         38, // down arrow
 753                                                         27, // escape
 754                                                         13, // enter
 755                                                         46, // delete
 756                                                         8 //   backspace
 757                                                 ];
 758                                                 if ( context.data.keypressedCount === 0 &&
 759                                                         e.which === context.data.keypressed &&
 760                                                         $.inArray( e.which, allowed ) !== -1
 761                                                 ) {
 762                                                         $.suggestions.keypress( e, context, context.data.keypressed );
 763                                                 }
 764                                         } )
 765                                         .blur( function () {
 766                                                 // When losing focus because of a mousedown
 767                                                 // on a suggestion, don't hide the suggestions
 768                                                 if ( context.data.mouseDownOn.length > 0 ) {
 769                                                         return;
 770                                                 }
 771                                                 $.suggestions.hide( context );
 772                                                 $.suggestions.cancel( context );
 773                                         } );
 774                         }
 775
 776                         // Store the context for next time
 777                         $( this ).data( 'suggestions-context', context );
 778                 } );
 779                 return returnValue !== undefined ? returnValue : $( this );
 780         };
 781
 782         /**
 783          * @class jQuery
 784          * @mixins jQuery.plugin.suggestions
 785          */
 786
 787 }( jQuery, mediaWiki ) );