resources/mediawiki/mediawiki.js

   1 /*
   2  * JavaScript backwards-compatibility and support
   3  */
   4
   5 // New fallback String trimming functionality, was introduced natively in JavaScript 1.8.1
   6 if (typeof String.prototype.trimx === 'undefined') {
   7 // Add removing trailing and leading whitespace functionality cross-browser
   8 // See also: http://blog.stevenlevithan.com/archives/faster-trim-javascript
   9         String.prototype.trim = function () {
  10                 return this.replace(/^\s+|\s+$/g, '');
  11         };
  12 }
  13 if (typeof String.prototype.trimLeft === 'undefined') {
  14         String.prototype.trimLeft = function () {
  15                 return this.replace(/^\s\s*/, "");
  16         };
  17 }
  18
  19 if (typeof String.prototype.trimRight === 'undefined') {
  20         String.prototype.trimRight = function () {
  21                 return this.replace(/\s\s*$/, "");
  22         };
  23 }
  24
  25 // Add array comparison functionality
  26 if (typeof Array.prototype.compare === 'undefined') {
  27         Array.prototype.compare = function (against) {
  28                 if (this.length !== against.length) {
  29                         return false;
  30                 }
  31                 for (var i = 0; i < against.length; i++) {
  32                         if (this[i].compare) {
  33                                 if (!this[i].compare(against[i])) {
  34                                         return false;
  35                                 }
  36                         }
  37                         if (this[i] !== against[i]) {
  38                                 return false;
  39                         }
  40                 }
  41                 return true;
  42         };
  43 }
  44
  45 // Make calling .indexOf() on an array work on older browsers
  46 if (typeof Array.prototype.indexOf === 'undefined') {
  47         Array.prototype.indexOf = function (needle) {
  48                 for (var i = 0; i < this.length; i++) {
  49                         if (this[i] === needle) {
  50                                 return i;
  51                         }
  52                 }
  53                 return -1;
  54         };
  55 }
  56
  57 /*
  58  * Core MediaWiki JavaScript Library
  59  */
  60 // Attach to window
  61 window.mediaWiki = new ( function( $ ) {
  62
  63         /* Constants */
  64
  65         // This will not change until we are 100% ready to turn off legacy globals
  66         var LEGACY_GLOBALS = true;
  67
  68         /* Private Members */
  69
  70         var that = this;
  71
  72         /* Prototypes */
  73
  74         this.prototypes = {
  75                 /*
  76                  * An object which allows single and multiple get/set/exists functionality on a list of key / value pairs
  77                  *
  78                  * @param {boolean} global whether to get/set/exists values on the window object or a private object
  79                  * @param {function} parser function to perform extra processing; in the form of function( value, options )
  80                  * @param {function} fallback function to format default fallback; in the form of function( key )
  81                  * where value is the data to be parsed and options is additional data passed through to the parser
  82                  */
  83                 'map': function( global, parser, fallback ) {
  84
  85                         /* Private Members */
  86
  87                         var that = this;
  88                         var values = global === true ? window : {};
  89
  90                         /* Public Methods */
  91
  92                         /**
  93                          * Gets one or more values
  94                          *
  95                          * If called with no arguments, all values will be returned. If a parser is in use, no parsing will take
  96                          * place when calling with no arguments or calling with an array of names.
  97                          *
  98                          * @param {mixed} selection string name of value to get, array of string names of values to get, or object
  99                          * of name/option pairs
 100                          * @param {object} options optional set of options which are also passed to a parser if in use; only used
 101                          * when selection is a string
 102                          * @format options
 103                          *      {
 104                          *              // Value to use if key does not exist
 105                          *              'fallback': ''
 106                          *      }
 107                          */
 108                         this.get = function( selection, options ) {
 109                                 if ( typeof selection === 'object' ) {
 110                                         var results = {};
 111                                         for ( var s in selection ) {
 112                                                 if ( selection.hasOwnProperty( s ) ) {
 113                                                         if ( typeof s === 'string' ) {
 114                                                                 return that.get( values[s], selection[s] );
 115                                                         } else {
 116                                                                 return that.get( selection[s] );
 117                                                         }
 118                                                 }
 119                                         }
 120                                         return results;
 121                                 } else if ( typeof selection === 'string' ) {
 122                                         if ( typeof values[selection] === 'undefined' ) {
 123                                                 if ( typeof options === 'object' && 'fallback' in options ) {
 124                                                         return options.fallback;
 125                                                 } else if ( typeof fallback === 'function' ) {
 126                                                         return fallback( selection );
 127                                                 } else {
 128                                                         return null;
 129                                                 }
 130                                         } else {
 131                                                 if ( typeof parser === 'function' ) {
 132                                                         return parser( values[selection], options );
 133                                                 } else {
 134                                                         return values[selection];
 135                                                 }
 136                                         }
 137                                 } else {
 138                                         return values;
 139                                 }
 140                         };
 141
 142                         /**
 143                          * Sets one or multiple configuration values using a key and a value or an object of keys and values
 144                          *
 145                          * @param {mixed} key string of name by which value will be made accessible, or object of name/value pairs
 146                          * @param {mixed} value optional value to set, only in use when key is a string
 147                          */
 148                         this.set = function( selection, value ) {
 149                                 if ( typeof selection === 'object' ) {
 150                                         for ( var s in selection ) {
 151                                                 values[s] = selection[s];
 152                                         }
 153                                 } else if ( typeof selection === 'string' && typeof value !== 'undefined' ) {
 154                                         values[selection] = value;
 155                                 }
 156                         };
 157
 158                         /**
 159                          * Checks if one or multiple configuration fields exist
 160                          */
 161                         this.exists = function( selection ) {
 162                                 if ( typeof keys === 'object' ) {
 163                                         for ( var s = 0; s < selection.length; s++ ) {
 164                                                 if ( !( selection[s] in values ) ) {
 165                                                         return false;
 166                                                 }
 167                                         }
 168                                         return true;
 169                                 } else {
 170                                         return selection in values;
 171                                 }
 172                         };
 173                 }
 174         };
 175
 176         /* Methods */
 177
 178         /*
 179          * Dummy function which in debug mode can be replaced with a function that does something clever
 180          */
 181         this.log = function() { };
 182
 183         /*
 184          * List of configuration values
 185          *
 186          * In legacy mode the values this object wraps will be in the global space
 187          */
 188         this.config = new this.prototypes.map( LEGACY_GLOBALS );
 189
 190         /*
 191          * Information about the current user
 192          */
 193         this.user = new ( function() {
 194
 195                 /* Public Members */
 196
 197                 this.options = new that.prototypes.map();
 198         } )();
 199
 200         /*
 201          * Basic parser, can be replaced with something more robust
 202          */
 203         this.parser = function( text, options ) {
 204                 if ( typeof options === 'object' && typeof options.parameters === 'object' ) {
 205                         text = text.replace( /\$(\d+)/g, function( str, match ) {
 206                                 var index = parseInt( match, 10 ) - 1;
 207                                 return index in options.parameters ? options.parameters[index] : '$' + match;
 208                         } );
 209                 }
 210                 return text;
 211         };
 212
 213         /*
 214          * Localization system
 215          */
 216         this.msg = new that.prototypes.map( false, this.parser, function( key ) { return '<' + key + '>'; } );
 217
 218         /*
 219          * Client-side module loader which integrates with the MediaWiki ResourceLoader
 220          */
 221         this.loader = new ( function() {
 222
 223                 /* Private Members */
 224
 225                 var that = this;
 226                 /*
 227                  * Mapping of registered modules
 228                  *
 229                  * The jquery module is pre-registered, because it must have already been provided for this object to have
 230                  * been built, and in debug mode jquery would have been provided through a unique loader request, making it
 231                  * impossible to hold back registration of jquery until after mediawiki.
 232                  *
 233                  * Format:
 234                  *      {
 235                  *              'moduleName': {
 236                  *                      'dependencies': ['required module', 'required module', ...], (or) function() {}
 237                  *                      'state': 'registered', 'loading', 'loaded', 'ready', or 'error'
 238                  *                      'script': function() {},
 239                  *                      'style': 'css code string',
 240                  *                      'messages': { 'key': 'value' },
 241                  *                      'version': ############## (unix timestamp)
 242                  *              }
 243                  *      }
 244                  */
 245                 var registry = {};
 246                 // List of modules which will be loaded as when ready
 247                 var batch = [];
 248                 // List of modules to be loaded
 249                 var queue = [];
 250                 // List of callback functions waiting for modules to be ready to be called
 251                 var jobs = [];
 252                 // Flag indicating that requests should be suspended
 253                 var suspended = true;
 254                 // Flag inidicating that document ready has occured
 255                 var ready = false;
 256
 257                 /* Private Methods */
 258
 259                 /**
 260                  * Generates an ISO8601 "basic" string from a UNIX timestamp
 261                  */
 262                 function formatVersionNumber( timestamp ) {
 263                         function pad( a, b, c ) {
 264                                 return [a < 10 ? '0' + a : a, b < 10 ? '0' + b : b, c < 10 ? '0' + c : c].join( '' );
 265                         }
 266                         var d = new Date()
 267                         d.setTime( timestamp * 1000 );
 268                         return [
 269                                 pad( d.getUTCFullYear(), d.getUTCMonth() + 1, d.getUTCDate() ), 'T',
 270                                 pad( d.getUTCHours(), d.getUTCMinutes(), d.getUTCSeconds() ), 'Z'
 271                         ].join( '' );
 272                 }
 273
 274                 /**
 275                  * Recursively resolves dependencies and detects circular references
 276                  */
 277                 function recurse( module, resolved, unresolved ) {
 278                         unresolved[unresolved.length] = module;
 279                         // Resolves dynamic loader function and replaces it with it's own results
 280                         if ( typeof registry[module].dependencies === 'function' ) {
 281                                 registry[module].dependencies = registry[module].dependencies();
 282                                 // Ensures the module's dependencies are always in an array
 283                                 if ( typeof registry[module].dependencies !== 'object' ) {
 284                                         registry[module].dependencies = [registry[module].dependencies];
 285                                 }
 286                         }
 287                         // Tracks down dependencies
 288                         for ( var n = 0; n < registry[module].dependencies.length; n++ ) {
 289                                 if ( resolved.indexOf( registry[module].dependencies[n] ) === -1 ) {
 290                                         if ( unresolved.indexOf( registry[module].dependencies[n] ) !== -1 ) {
 291                                                 throw new Error(
 292                                                         'Circular reference detected: ' + module + ' -> ' + registry[module].dependencies[n]
 293                                                 );
 294                                         }
 295                                         recurse( registry[module].dependencies[n], resolved, unresolved );
 296                                 }
 297                         }
 298                         resolved[resolved.length] = module;
 299                         unresolved.splice( unresolved.indexOf( module ), 1 );
 300                 }
 301
 302                 /**
 303                  * Gets a list of modules names that a module dependencies in their proper dependency order
 304                  *
 305                  * @param mixed string module name or array of string module names
 306                  * @return list of dependencies
 307                  * @throws Error if circular reference is detected
 308                  */
 309                 function resolve( module, resolved, unresolved ) {
 310                         // Allow calling with an array of module names
 311                         if ( typeof module === 'object' ) {
 312                                 var modules = [];
 313                                 for ( var m = 0; m < module.length; m++ ) {
 314                                         var dependencies = resolve( module[m] );
 315                                         for ( var n = 0; n < dependencies.length; n++ ) {
 316                                                 modules[modules.length] = dependencies[n];
 317                                         }
 318                                 }
 319                                 return modules;
 320                         } else if ( typeof module === 'string' ) {
 321                                 // Undefined modules have no dependencies
 322                                 if ( !( module in registry ) ) {
 323                                         return [];
 324                                 }
 325                                 var resolved = [];
 326                                 recurse( module, resolved, [] );
 327                                 return resolved;
 328                         }
 329                         throw new Error( 'Invalid module argument: ' + module );
 330                 };
 331
 332                 /**
 333                  * Narrows a list of module names down to those matching a specific state. Possible states are 'undefined',
 334                  * 'registered', 'loading', 'loaded', or 'ready'
 335                  *
 336                  * @param mixed string or array of strings of module states to filter by
 337                  * @param array list of module names to filter (optional, all modules will be used by default)
 338                  * @return array list of filtered module names
 339                  */
 340                 function filter( states, modules ) {
 341                         // Allow states to be given as a string
 342                         if ( typeof states === 'string' ) {
 343                                 states = [states];
 344                         }
 345                         // If called without a list of modules, build and use a list of all modules
 346                         var list = [];
 347                         if ( typeof modules === 'undefined' ) {
 348                                 modules = [];
 349                                 for ( module in registry ) {
 350                                         modules[modules.length] = module;
 351                                 }
 352                         }
 353                         // Build a list of modules which are in one of the specified states
 354                         for ( var s = 0; s < states.length; s++ ) {
 355                                 for ( var m = 0; m < modules.length; m++ ) {
 356                                         if (
 357                                                 ( states[s] == 'undefined' && typeof registry[modules[m]] === 'undefined' ) ||
 358                                                 ( typeof registry[modules[m]] === 'object' && registry[modules[m]].state === states[s] )
 359                                         ) {
 360                                                 list[list.length] = modules[m];
 361                                         }
 362                                 }
 363                         }
 364                         return list;
 365                 }
 366
 367                 /**
 368                  * Executes a loaded module, making it ready to use
 369                  *
 370                  * @param string module name to execute
 371                  */
 372                 function execute( module ) {
 373                         if ( typeof registry[module] === 'undefined' ) {
 374                                 throw new Error( 'Module has not been registered yet: ' + module );
 375                         } else if ( registry[module].state === 'registered' ) {
 376                                 throw new Error( 'Module has not been requested from the server yet: ' + module );
 377                         } else if ( registry[module].state === 'loading' ) {
 378                                 throw new Error( 'Module has not completed loading yet: ' + module );
 379                         } else if ( registry[module].state === 'ready' ) {
 380                                 throw new Error( 'Module has already been loaded: ' + module );
 381                         }
 382                         // Add style sheet to document
 383                         if ( typeof registry[module].style === 'string' && registry[module].style.length ) {
 384                                 $( 'head' ).append( '<style type="text/css">' + registry[module].style + '</style>' );
 385                         } else if ( typeof registry[module].style === 'object' && !( registry[module].style instanceof Array ) ) {
 386                                 for ( var media in registry[module].style ) {
 387                                         $( 'head' ).append(
 388                                                 '<style type="text/css" media="' + media + '">' + registry[module].style[media] + '</style>'
 389                                         );
 390                                 }
 391                         }
 392                         // Add localizations to message system
 393                         if ( typeof registry[module].messages === 'object' ) {
 394                                 mediaWiki.msg.set( registry[module].messages );
 395                         }
 396                         // Execute script
 397                         try {
 398                                 registry[module].script();
 399                                 registry[module].state = 'ready';
 400                                 // Run jobs who's dependencies have just been met
 401                                 for ( var j = 0; j < jobs.length; j++ ) {
 402                                         if ( filter( 'ready', jobs[j].dependencies ).compare( jobs[j].dependencies ) ) {
 403                                                 if ( typeof jobs[j].ready === 'function' ) {
 404                                                         jobs[j].ready();
 405                                                 }
 406                                                 jobs.splice( j, 1 );
 407                                                 j--;
 408                                         }
 409                                 }
 410                                 // Execute modules who's dependencies have just been met
 411                                 for ( r in registry ) {
 412                                         if ( registry[r].state == 'loaded' ) {
 413                                                 if ( filter( ['ready'], registry[r].dependencies ).compare( registry[r].dependencies ) ) {
 414                                                         execute( r );
 415                                                 }
 416                                         }
 417                                 }
 418                         } catch ( e ) {
 419                                 mediaWiki.log( 'Exception thrown by ' + module + ': ' + e.message );
 420                                 mediaWiki.log( e );
 421                                 registry[module].state = 'error';
 422                                 // Run error callbacks of jobs affected by this condition
 423                                 for ( var j = 0; j < jobs.length; j++ ) {
 424                                         if ( jobs[j].dependencies.indexOf( module ) !== -1 ) {
 425                                                 if ( typeof jobs[j].error === 'function' ) {
 426                                                         jobs[j].error();
 427                                                 }
 428                                                 jobs.splice( j, 1 );
 429                                                 j--;
 430                                         }
 431                                 }
 432                         }
 433                 }
 434
 435                 /**
 436                  * Adds a dependencies to the queue with optional callbacks to be run when the dependencies are ready or fail
 437                  *
 438                  * @param mixed string moulde name or array of string module names
 439                  * @param function ready callback to execute when all dependencies are ready
 440                  * @param function error callback to execute when any dependency fails
 441                  */
 442                 function request( dependencies, ready, error ) {
 443                         // Allow calling by single module name
 444                         if ( typeof dependencies === 'string' ) {
 445                                 dependencies = [dependencies];
 446                                 if ( dependencies[0] in registry ) {
 447                                         for ( var n = 0; n < registry[dependencies[0]].dependencies.length; n++ ) {
 448                                                 dependencies[dependencies.length] = registry[dependencies[0]].dependencies[n];
 449                                         }
 450                                 }
 451                         }
 452                         // Add ready and error callbacks if they were given
 453                         if ( arguments.length > 1 ) {
 454                                 jobs[jobs.length] = {
 455                                         'dependencies': filter( ['undefined', 'registered', 'loading', 'loaded'], dependencies ),
 456                                         'ready': ready,
 457                                         'error': error
 458                                 };
 459                         }
 460                         // Queue up any dependencies that are undefined or registered
 461                         dependencies = filter( ['undefined', 'registered'], dependencies );
 462                         for ( var n = 0; n < dependencies.length; n++ ) {
 463                                 if ( queue.indexOf( dependencies[n] ) === -1 ) {
 464                                         queue[queue.length] = dependencies[n];
 465                                 }
 466                         }
 467                         // Work the queue
 468                         that.work();
 469                 }
 470
 471                 function sortQuery(o) {
 472                         var sorted = {}, key, a = [];
 473                         for ( key in o ) {
 474                                 if ( o.hasOwnProperty( key ) ) {
 475                                         a.push( key );
 476                                 }
 477                         }
 478                         a.sort();
 479                         for ( key = 0; key < a.length; key++ ) {
 480                                 sorted[a[key]] = o[a[key]];
 481                         }
 482                         return sorted;
 483                 }
 484
 485                 /* Public Methods */
 486
 487                 /**
 488                  * Requests dependencies from server, loading and executing when things when ready.
 489                  */
 490                 this.work = function() {
 491                         // Appends a list of modules to the batch
 492                         for ( var q = 0; q < queue.length; q++ ) {
 493                                 // Only request modules which are undefined or registered
 494                                 if ( !( queue[q] in registry ) || registry[queue[q]].state == 'registered' ) {
 495                                         // Prevent duplicate entries
 496                                         if ( batch.indexOf( queue[q] ) === -1 ) {
 497                                                 batch[batch.length] = queue[q];
 498                                                 // Mark registered modules as loading
 499                                                 if ( queue[q] in registry ) {
 500                                                         registry[queue[q]].state = 'loading';
 501                                                 }
 502                                         }
 503                                 }
 504                         }
 505                         // Clean up the queue
 506                         queue = [];
 507                         // After document ready, handle the batch
 508                         if ( !suspended && batch.length ) {
 509                                 // Always order modules alphabetically to help reduce cache misses for otherwise identical content
 510                                 batch.sort();
 511                                 // Build a list of request parameters
 512                                 var base = {
 513                                         'skin': mediaWiki.config.get( 'skin' ),
 514                                         'lang': mediaWiki.config.get( 'wgUserLanguage' ),
 515                                         'debug': mediaWiki.config.get( 'debug' )
 516                                 };
 517                                 // Extend request parameters with a list of modules in the batch
 518                                 var requests = [];
 519                                 // Split into groups
 520                                 var groups = {};
 521                                 for ( var b = 0; b < batch.length; b++ ) {
 522                                         var group = registry[batch[b]].group;
 523                                         if ( !( group in groups ) ) {
 524                                                 groups[group] = [];
 525                                         }
 526                                         groups[group][groups[group].length] = batch[b];
 527                                 }
 528                                 for ( var group in groups ) {
 529                                         // Calculate the highest timestamp
 530                                         var version = 0;
 531                                         for ( var g = 0; g < groups[group].length; g++ ) {
 532                                                 if ( registry[groups[group][g]].version > version ) {
 533                                                         version = registry[groups[group][g]].version;
 534                                                 }
 535                                         }
 536                                         requests[requests.length] = $.extend(
 537                                                 { 'modules': groups[group].join( '|' ), 'version': formatVersionNumber( version ) }, base
 538                                         );
 539                                 }
 540                                 // Clear the batch - this MUST happen before we append the script element to the body or it's
 541                                 // possible that the script will be locally cached, instantly load, and work the batch again,
 542                                 // all before we've cleared it causing each request to include modules which are already loaded
 543                                 batch = [];
 544                                 // Asynchronously append a script tag to the end of the body
 545                                 function request() {
 546                                         var html = '';
 547                                         for ( var r = 0; r < requests.length; r++ ) {
 548                                                 requests[r] = sortQuery( requests[r] );
 549                                                 // Build out the HTML
 550                                                 var src = mediaWiki.config.get( 'wgLoadScript' ) + '?' + $.param( requests[r] );
 551                                                 html += '<script type="text/javascript" src="' + src + '"></script>';
 552                                         }
 553                                         return html;
 554                                 }
 555                                 // Load asynchronously after doumument ready
 556                                 if ( ready ) {
 557                                         setTimeout(  function() { $( 'body' ).append( request() ); }, 0 )
 558                                 } else {
 559                                         document.write( request() );
 560                                 }
 561                         }
 562                 };
 563
 564                 /**
 565                  * Registers a module, letting the system know about it and it's dependencies. loader.js files contain calls
 566                  * to this function.
 567                  */
 568                 this.register = function( module, version, dependencies, group ) {
 569                         // Allow multiple registration
 570                         if ( typeof module === 'object' ) {
 571                                 for ( var m = 0; m < module.length; m++ ) {
 572                                         if ( typeof module[m] === 'string' ) {
 573                                                 that.register( module[m] );
 574                                         } else if ( typeof module[m] === 'object' ) {
 575                                                 that.register.apply( that, module[m] );
 576                                         }
 577                                 }
 578                                 return;
 579                         }
 580                         // Validate input
 581                         if ( typeof module !== 'string' ) {
 582                                 throw new Error( 'module must be a string, not a ' + typeof module );
 583                         }
 584                         if ( typeof registry[module] !== 'undefined' ) {
 585                                 throw new Error( 'module already implemeneted: ' + module );
 586                         }
 587                         // List the module as registered
 588                         registry[module] = {
 589                                 'state': 'registered',
 590                                 'group': typeof group === 'string' ? group : null,
 591                                 'dependencies': [],
 592                                 'version': typeof version !== 'undefined' ? parseInt( version ) : 0
 593                         };
 594                         if ( typeof dependencies === 'string' ) {
 595                                 // Allow dependencies to be given as a single module name
 596                                 registry[module].dependencies = [dependencies];
 597                         } else if ( typeof dependencies === 'object' || typeof dependencies === 'function' ) {
 598                                 // Allow dependencies to be given as an array of module names or a function which returns an array
 599                                 registry[module].dependencies = dependencies;
 600                         }
 601                 };
 602
 603                 /**
 604                  * Implements a module, giving the system a course of action to take upon loading. Results of a request for
 605                  * one or more modules contain calls to this function.
 606                  */
 607                 this.implement = function( module, script, style, localization ) {
 608                         // Automaically register module
 609                         if ( typeof registry[module] === 'undefined' ) {
 610                                 that.register( module );
 611                         }
 612                         // Validate input
 613                         if ( typeof script !== 'function' ) {
 614                                 throw new Error( 'script must be a function, not a ' + typeof script );
 615                         }
 616                         if ( typeof style !== 'undefined' && typeof style !== 'string' && typeof style !== 'object' ) {
 617                                 throw new Error( 'style must be a string or object, not a ' + typeof style );
 618                         }
 619                         if ( typeof localization !== 'undefined' && typeof localization !== 'object' ) {
 620                                 throw new Error( 'localization must be an object, not a ' + typeof localization );
 621                         }
 622                         if ( typeof registry[module] !== 'undefined' && typeof registry[module].script !== 'undefined' ) {
 623                                 throw new Error( 'module already implemeneted: ' + module );
 624                         }
 625                         // Mark module as loaded
 626                         registry[module].state = 'loaded';
 627                         // Attach components
 628                         registry[module].script = script;
 629                         if ( typeof style === 'string' || typeof style === 'object' && !( style instanceof Array ) ) {
 630                                 registry[module].style = style;
 631                         }
 632                         if ( typeof localization === 'object' ) {
 633                                 registry[module].messages = localization;
 634                         }
 635                         // Execute or queue callback
 636                         if ( filter( ['ready'], registry[module].dependencies ).compare( registry[module].dependencies ) ) {
 637                                 execute( module );
 638                         } else {
 639                                 request( module );
 640                         }
 641                 };
 642
 643                 /**
 644                  * Executes a function as soon as one or more required modules are ready
 645                  *
 646                  * @param mixed string or array of strings of modules names the callback dependencies to be ready before
 647                  * executing
 648                  * @param function callback to execute when all dependencies are ready (optional)
 649                  * @param function callback to execute when if dependencies have a errors (optional)
 650                  */
 651                 this.using = function( dependencies, ready, error ) {
 652                         // Validate input
 653                         if ( typeof dependencies !== 'object' && typeof dependencies !== 'string' ) {
 654                                 throw new Error( 'dependencies must be a string or an array, not a ' + typeof dependencies )
 655                         }
 656                         // Allow calling with a single dependency as a string
 657                         if ( typeof dependencies === 'string' ) {
 658                                 dependencies = [dependencies];
 659                         }
 660                         // Resolve entire dependency map
 661                         dependencies = resolve( dependencies );
 662                         // If all dependencies are met, execute ready immediately
 663                         if ( filter( ['ready'], dependencies ).compare( dependencies ) ) {
 664                                 if ( typeof ready === 'function' ) {
 665                                         ready();
 666                                 }
 667                         }
 668                         // If any dependencies have errors execute error immediately
 669                         else if ( filter( ['error'], dependencies ).length ) {
 670                                 if ( typeof error === 'function' ) {
 671                                         error();
 672                                 }
 673                         }
 674                         // Since some dependencies are not yet ready, queue up a request
 675                         else {
 676                                 request( dependencies, ready, error );
 677                         }
 678                 };
 679
 680                 /**
 681                  * Loads an external script or one or more modules for future use
 682                  *
 683                  * @param {mixed} modules either the name of a module, array of modules, or a URL of an external script or style
 684                  * @param {string} type mime-type to use if calling with a URL of an external script or style; acceptable values
 685                  * are "text/css" and "text/javascript"; if no type is provided, text/javascript is assumed
 686                  */
 687                 this.load = function( modules, type ) {
 688                         // Validate input
 689                         if ( typeof modules !== 'object' && typeof modules !== 'string' ) {
 690                                 throw new Error( 'dependencies must be a string or an array, not a ' + typeof dependencies )
 691                         }
 692                         // Allow calling with an external script or single dependency as a string
 693                         if ( typeof modules === 'string' ) {
 694                                 // Support adding arbitrary external scripts
 695                                 if ( modules.substr( 0, 7 ) == 'http://' || modules.substr( 0, 8 ) == 'https://' ) {
 696                                         if ( type === 'text/css' ) {
 697                                                 $( 'head' ).append( $( '<link rel="stylesheet" type="text/css" />' ).attr( 'href', modules ) );
 698                                                 return true;
 699                                         } else if ( type === 'text/javascript' || typeof type === 'undefined' ) {
 700                                                 var script = '<script type="text/javascript" src="' + modules + '"></script>';
 701                                                 if ( ready ) {
 702                                                         $( 'body' ).append( script );
 703                                                 } else {
 704                                                         document.write( script );
 705                                                 }
 706                                                 return true;
 707                                         }
 708                                         // Unknown type
 709                                         return false;
 710                                 }
 711                                 // Called with single module
 712                                 modules = [modules];
 713                         }
 714                         // Resolve entire dependency map
 715                         modules = resolve( modules );
 716                         // If all modules are ready, nothing dependency be done
 717                         if ( filter( ['ready'], modules ).compare( modules ) ) {
 718                                 return true;
 719                         }
 720                         // If any modules have errors return false
 721                         else if ( filter( ['error'], modules ).length ) {
 722                                 return false;
 723                         }
 724                         // Since some modules are not yet ready, queue up a request
 725                         else {
 726                                 request( modules );
 727                                 return true;
 728                         }
 729                 };
 730
 731                 /**
 732                  * Flushes the request queue and begin executing load requests on demand
 733                  */
 734                 this.go = function() {
 735                         suspended = false;
 736                         that.work();
 737                 };
 738
 739                 /**
 740                  * Changes the state of a module
 741                  *
 742                  * @param mixed module string module name or object of module name/state pairs
 743                  * @param string state string state name
 744                  */
 745                 this.state = function( module, state ) {
 746                         if ( typeof module === 'object' ) {
 747                                 for ( var m in module ) {
 748                                         that.state( m, module[m] );
 749                                 }
 750                                 return;
 751                         }
 752                         if ( !( module in registry ) ) {
 753                                 that.register( module );
 754                         }
 755                         registry[module].state = state;
 756                 };
 757
 758                 /**
 759                  * Gets the version of a module
 760                  *
 761                  * @param string module name of module to get version for
 762                  */
 763                 this.version = function( module ) {
 764                         if ( module in registry && 'version' in registry[module] ) {
 765                                 return formatVersionNumber( registry[module].version );
 766                         }
 767                         return null;
 768                 }
 769
 770                 /* Cache document ready status */
 771
 772                 $(document).ready( function() { ready = true; } );
 773         } )();
 774
 775         /* Extension points */
 776
 777         this.legacy = {};
 778
 779 } )( jQuery );
 780
 781 /* Auto-register from pre-loaded startup scripts */
 782
 783 if ( typeof startUp === 'function' ) {
 784         startUp();
 785         delete startUp;
 786 }
 787
 788 // Alias $j to jQuery for backwards compatibility
 789 window.$j = jQuery;
 790 window.mw = mediaWiki;