resources/mediawiki/mediawiki.js

   1 /*
   2  * JavaScript backwards-compatibility and support
   3  */
   4
   5 // Implementation of string trimming functionality introduced natively in JavaScript 1.8.1
   6 if ( typeof String.prototype.trim === '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+$/g, '' );
  11         };
  12 }
  13 if ( typeof String.prototype.trimLeft === 'undefined' ) {
  14         String.prototype.trimLeft = function() {
  15                 return this.replace( /^\s\s*/, "" );
  16         };
  17 }
  18 if ( typeof String.prototype.trimRight === 'undefined' ) {
  19         String.prototype.trimRight = function() {
  20                 return this.replace(/\s\s*$/, "");
  21         };
  22 }
  23
  24 /*
  25  * Prototype enhancements
  26  */
  27
  28 // Capitalize the first character of the given string
  29 if ( typeof String.prototype.ucFirst === 'undefined' ) {
  30         String.prototype.ucFirst = function() {
  31                 return this.substr(0, 1).toUpperCase() + this.substr(1, this.length);
  32         };
  33 }
  34
  35 // Escape all RegExp special characters such that the result can be safely used
  36 // in a RegExp as a literal.
  37 if ( typeof String.prototype.escapeRE === 'undefined' ) {
  38         String.prototype.escapeRE = function() {
  39                 return this.replace (/([\\{}()|.?*+^$\[\]])/g, "\\$1");
  40         };
  41 }
  42
  43 /*
  44  * Core MediaWiki JavaScript Library
  45  */
  46
  47 // Attach to window
  48 window.mediaWiki = new ( function( $ ) {
  49
  50         /* Constants */
  51
  52         // This will not change until we are 100% ready to turn off legacy globals
  53         var LEGACY_GLOBALS = true;
  54
  55         /* Private Members */
  56
  57         // List of messages that have been requested to be loaded
  58         var messageQueue = {};
  59
  60         /* Prototypes */
  61
  62         /**
  63          * An object which allows single and multiple get/set/exists functionality on a list of key / value pairs.
  64          *
  65          * @param {boolean} global Whether to get/set/exists values on the window object or a private object
  66          */
  67         function Map( global ) {
  68                 this.values = ( global === true ) ? window : {};
  69         };
  70
  71         /**
  72          * Gets the value of a key, or a list of key/value pairs for an array of keys.
  73          *
  74          * If called with no arguments, all values will be returned.
  75          *
  76          * @param {mixed} selection Key or array of keys to get values for
  77          * @param {mixed} fallback Value to use in case key(s) do not exist (optional)
  78          */
  79         Map.prototype.get = function( selection, fallback ) {
  80                 if ( typeof selection === 'object' ) {
  81                         selection = $.makeArray( selection );
  82                         var results = {};
  83                         for ( var i = 0; i < selection.length; i++ ) {
  84                                 results[selection[i]] = this.get( selection[i], fallback );
  85                         }
  86                         return results;
  87                 } else if ( typeof selection === 'string' ) {
  88                         if ( typeof this.values[selection] === 'undefined' ) {
  89                                 if ( typeof fallback !== 'undefined' ) {
  90                                         return fallback;
  91                                 }
  92                                 return null;
  93                         }
  94                         return this.values[selection];
  95                 }
  96                 return this.values;
  97         };
  98
  99         /**
 100          * Sets one or multiple key/value pairs.
 101          *
 102          * @param {mixed} selection Key or object of key/value pairs to set
 103          * @param {mixed} value Value to set (optional, only in use when key is a string)
 104          */
 105         Map.prototype.set = function( selection, value ) {
 106                 if ( typeof selection === 'object' ) {
 107                         for ( var s in selection ) {
 108                                 this.values[s] = selection[s];
 109                         }
 110                 } else if ( typeof selection === 'string' && typeof value !== 'undefined' ) {
 111                         this.values[selection] = value;
 112                 }
 113         };
 114
 115         /**
 116          * Checks if one or multiple keys exist.
 117          *
 118          * @param {mixed} key Key or array of keys to check
 119          * @return {boolean} Existence of key(s)
 120          */
 121         Map.prototype.exists = function( selection ) {
 122                 if ( typeof keys === 'object' ) {
 123                         for ( var s = 0; s < selection.length; s++ ) {
 124                                 if ( !( selection[s] in this.values ) ) {
 125                                         return false;
 126                                 }
 127                         }
 128                         return true;
 129                 } else {
 130                         return selection in this.values;
 131                 }
 132         };
 133
 134         /**
 135          * Message object, similar to Message in PHP
 136          */
 137         function Message( map, key, parameters ) {
 138                 this.format = 'parse';
 139                 this.map = map;
 140                 this.key = key;
 141                 this.parameters = typeof parameters === 'undefined' ? [] : $.makeArray( parameters );
 142         };
 143
 144         /**
 145          * Appends parameters for replacement
 146          *
 147          * @param {mixed} args First in a list of variadic arguments to append as message parameters
 148          */
 149         Message.prototype.params = function( parameters ) {
 150                 for ( var i = 0; i < parameters.length; i++ ) {
 151                         this.parameters[this.parameters.length] = parameters[i];
 152                 }
 153                 return this;
 154         };
 155
 156         /**
 157          * Converts message object to it's string form based on the state of format
 158          *
 159          * @return {string} String form of message
 160          */
 161         Message.prototype.toString = function() {
 162                 if ( !this.map.exists( this.key ) ) {
 163                         // Return <key> if key does not exist
 164                         return '<' + this.key + '>';
 165                 }
 166                 var text = this.map.get( this.key );
 167                 var parameters = this.parameters;
 168                 text = text.replace( /\$(\d+)/g, function( string, match ) {
 169                         var index = parseInt( match, 10 ) - 1;
 170                         return index in parameters ? parameters[index] : '$' + match;
 171                 } );
 172                 /* This should be fixed up when we have a parser
 173                 if ( this.format === 'parse' && 'language' in mediaWiki ) {
 174                         text = mediaWiki.language.parse( text );
 175                 }
 176                 */
 177                 return text;
 178         };
 179
 180         /**
 181          * Changes format to parse and converts message to string
 182          *
 183          * @return {string} String form of parsed message
 184          */
 185         Message.prototype.parse = function() {
 186                 this.format = 'parse';
 187                 return this.toString();
 188         };
 189
 190         /**
 191          * Changes format to plain and converts message to string
 192          *
 193          * @return {string} String form of plain message
 194          */
 195         Message.prototype.plain = function() {
 196                 this.format = 'plain';
 197                 return this.toString();
 198         };
 199
 200         /**
 201          * Checks if message exists
 202          *
 203          * @return {string} String form of parsed message
 204          */
 205         Message.prototype.exists = function() {
 206                 return this.map.exists( this.key );
 207         };
 208
 209         /**
 210          * User object
 211          */
 212         function User() {
 213                 this.options = new Map();
 214         }
 215
 216         /* Public Members */
 217
 218         /*
 219          * Dummy function which in debug mode can be replaced with a function that does something clever
 220          */
 221         this.log = function() { };
 222
 223         /*
 224          * List of configuration values
 225          *
 226          * In legacy mode the values this object wraps will be in the global space
 227          */
 228         this.config = new Map( LEGACY_GLOBALS );
 229
 230         /*
 231          * Information about the current user
 232          */
 233         this.user = new User();
 234
 235         /*
 236          * Localization system
 237          */
 238         this.messages = new Map();
 239
 240         /* Public Methods */
 241
 242         /**
 243          * Gets a message object, similar to wfMessage()
 244          *
 245          * @param {string} key Key of message to get
 246          * @param {mixed} params First argument in a list of variadic arguments, each a parameter for $
 247          * replacement
 248          */
 249         this.message = function( key, parameters ) {
 250                 // Support variadic arguments
 251                 if ( typeof parameters !== 'undefined' ) {
 252                         parameters = $.makeArray( arguments );
 253                         parameters.shift();
 254                 } else {
 255                         parameters = [];
 256                 }
 257                 return new Message( mediaWiki.messages, key, parameters );
 258         };
 259
 260         /**
 261          * Gets a message string, similar to wfMsg()
 262          *
 263          * @param {string} key Key of message to get
 264          * @param {mixed} params First argument in a list of variadic arguments, each a parameter for $
 265          * replacement
 266          */
 267         this.msg = function( key, parameters ) {
 268                 return mediaWiki.message.apply( mediaWiki.message, arguments ).toString();
 269         };
 270
 271         /**
 272          * Client-side module loader which integrates with the MediaWiki ResourceLoader
 273          */
 274         this.loader = new ( function() {
 275
 276                 /* Private Members */
 277
 278                 /**
 279                  * Mapping of registered modules
 280                  *
 281                  * The jquery module is pre-registered, because it must have already been provided for this object to have
 282                  * been built, and in debug mode jquery would have been provided through a unique loader request, making it
 283                  * impossible to hold back registration of jquery until after mediawiki.
 284                  *
 285                  * Format:
 286                  *      {
 287                  *              'moduleName': {
 288                  *                      'dependencies': ['required module', 'required module', ...], (or) function() {}
 289                  *                      'state': 'registered', 'loading', 'loaded', 'ready', or 'error'
 290                  *                      'script': function() {},
 291                  *                      'style': 'css code string',
 292                  *                      'messages': { 'key': 'value' },
 293                  *                      'version': ############## (unix timestamp)
 294                  *              }
 295                  *      }
 296                  */
 297                 var registry = {};
 298                 // List of modules which will be loaded as when ready
 299                 var batch = [];
 300                 // List of modules to be loaded
 301                 var queue = [];
 302                 // List of callback functions waiting for modules to be ready to be called
 303                 var jobs = [];
 304                 // Flag indicating that requests should be suspended
 305                 var suspended = true;
 306                 // Flag inidicating that document ready has occured
 307                 var ready = false;
 308
 309                 /* Private Methods */
 310
 311                 function compare( a, b ) {
 312                         if ( a.length != b.length ) {
 313                                 return false;
 314                         }
 315                         for ( var i = 0; i < b.length; i++ ) {
 316                                 if ( $.isArray( a[i] ) ) {
 317                                         if ( !compare( a[i], b[i] ) ) {
 318                                                 return false;
 319                                         }
 320                                 }
 321                                 if ( a[i] !== b[i] ) {
 322                                         return false;
 323                                 }
 324                         }
 325                         return true;
 326                 };
 327
 328                 /**
 329                  * Generates an ISO8601 "basic" string from a UNIX timestamp
 330                  */
 331                 function formatVersionNumber( timestamp ) {
 332                         function pad( a, b, c ) {
 333                                 return [a < 10 ? '0' + a : a, b < 10 ? '0' + b : b, c < 10 ? '0' + c : c].join( '' );
 334                         }
 335                         var d = new Date()
 336                         d.setTime( timestamp * 1000 );
 337                         return [
 338                                 pad( d.getUTCFullYear(), d.getUTCMonth() + 1, d.getUTCDate() ), 'T',
 339                                 pad( d.getUTCHours(), d.getUTCMinutes(), d.getUTCSeconds() ), 'Z'
 340                         ].join( '' );
 341                 }
 342
 343                 /**
 344                  * Recursively resolves dependencies and detects circular references
 345                  */
 346                 function recurse( module, resolved, unresolved ) {
 347                         if ( typeof registry[module] === 'undefined' ) {
 348                                 throw new Error( 'Unknown dependency: ' + module );
 349                         }
 350                         // Resolves dynamic loader function and replaces it with it's own results
 351                         if ( typeof registry[module].dependencies === 'function' ) {
 352                                 registry[module].dependencies = registry[module].dependencies();
 353                                 // Ensures the module's dependencies are always in an array
 354                                 if ( typeof registry[module].dependencies !== 'object' ) {
 355                                         registry[module].dependencies = [registry[module].dependencies];
 356                                 }
 357                         }
 358                         // Tracks down dependencies
 359                         for ( var n = 0; n < registry[module].dependencies.length; n++ ) {
 360                                 if ( $.inArray( registry[module].dependencies[n], resolved ) === -1 ) {
 361                                         if ( $.inArray( registry[module].dependencies[n], unresolved ) !== -1 ) {
 362                                                 throw new Error(
 363                                                         'Circular reference detected: ' + module + ' -> ' + registry[module].dependencies[n]
 364                                                 );
 365                                         }
 366                                         recurse( registry[module].dependencies[n], resolved, unresolved );
 367                                 }
 368                         }
 369                         resolved[resolved.length] = module;
 370                         unresolved.splice( $.inArray( module, unresolved ), 1 );
 371                 }
 372
 373                 /**
 374                  * Gets a list of modules names that a module dependencies in their proper dependency order
 375                  *
 376                  * @param mixed string module name or array of string module names
 377                  * @return list of dependencies
 378                  * @throws Error if circular reference is detected
 379                  */
 380                 function resolve( module, resolved, unresolved ) {
 381                         // Allow calling with an array of module names
 382                         if ( typeof module === 'object' ) {
 383                                 var modules = [];
 384                                 for ( var m = 0; m < module.length; m++ ) {
 385                                         var dependencies = resolve( module[m] );
 386                                         for ( var n = 0; n < dependencies.length; n++ ) {
 387                                                 modules[modules.length] = dependencies[n];
 388                                         }
 389                                 }
 390                                 return modules;
 391                         } else if ( typeof module === 'string' ) {
 392                                 // Undefined modules have no dependencies
 393                                 if ( !( module in registry ) ) {
 394                                         return [];
 395                                 }
 396                                 var resolved = [];
 397                                 recurse( module, resolved, [] );
 398                                 return resolved;
 399                         }
 400                         throw new Error( 'Invalid module argument: ' + module );
 401                 };
 402
 403                 /**
 404                  * Narrows a list of module names down to those matching a specific state. Possible states are 'undefined',
 405                  * 'registered', 'loading', 'loaded', or 'ready'
 406                  *
 407                  * @param mixed string or array of strings of module states to filter by
 408                  * @param array list of module names to filter (optional, all modules will be used by default)
 409                  * @return array list of filtered module names
 410                  */
 411                 function filter( states, modules ) {
 412                         // Allow states to be given as a string
 413                         if ( typeof states === 'string' ) {
 414                                 states = [states];
 415                         }
 416                         // If called without a list of modules, build and use a list of all modules
 417                         var list = [];
 418                         if ( typeof modules === 'undefined' ) {
 419                                 modules = [];
 420                                 for ( module in registry ) {
 421                                         modules[modules.length] = module;
 422                                 }
 423                         }
 424                         // Build a list of modules which are in one of the specified states
 425                         for ( var s = 0; s < states.length; s++ ) {
 426                                 for ( var m = 0; m < modules.length; m++ ) {
 427                                         if (
 428                                                 ( states[s] == 'undefined' && typeof registry[modules[m]] === 'undefined' ) ||
 429                                                 ( typeof registry[modules[m]] === 'object' && registry[modules[m]].state === states[s] )
 430                                         ) {
 431                                                 list[list.length] = modules[m];
 432                                         }
 433                                 }
 434                         }
 435                         return list;
 436                 }
 437
 438                 /**
 439                  * Executes a loaded module, making it ready to use
 440                  *
 441                  * @param string module name to execute
 442                  */
 443                 function execute( module ) {
 444                         if ( typeof registry[module] === 'undefined' ) {
 445                                 throw new Error( 'Module has not been registered yet: ' + module );
 446                         } else if ( registry[module].state === 'registered' ) {
 447                                 throw new Error( 'Module has not been requested from the server yet: ' + module );
 448                         } else if ( registry[module].state === 'loading' ) {
 449                                 throw new Error( 'Module has not completed loading yet: ' + module );
 450                         } else if ( registry[module].state === 'ready' ) {
 451                                 throw new Error( 'Module has already been loaded: ' + module );
 452                         }
 453                         // Add style sheet to document
 454                         if ( typeof registry[module].style === 'string' && registry[module].style.length ) {
 455                                 $( 'head' ).append( '<style type="text/css">' + registry[module].style + '</style>' );
 456                         } else if ( typeof registry[module].style === 'object' && !( registry[module].style instanceof Array ) ) {
 457                                 for ( var media in registry[module].style ) {
 458                                         $( 'head' ).append(
 459                                                 '<style type="text/css" media="' + media + '">' + registry[module].style[media] + '</style>'
 460                                         );
 461                                 }
 462                         }
 463                         // Add localizations to message system
 464                         if ( typeof registry[module].messages === 'object' ) {
 465                                 mediaWiki.messages.set( registry[module].messages );
 466                         }
 467                         // Execute script
 468                         try {
 469                                 registry[module].script();
 470                                 registry[module].state = 'ready';
 471                                 // Run jobs who's dependencies have just been met
 472                                 for ( var j = 0; j < jobs.length; j++ ) {
 473                                         if ( compare( filter( 'ready', jobs[j].dependencies ), jobs[j].dependencies ) ) {
 474                                                 if ( typeof jobs[j].ready === 'function' ) {
 475                                                         jobs[j].ready();
 476                                                 }
 477                                                 jobs.splice( j, 1 );
 478                                                 j--;
 479                                         }
 480                                 }
 481                                 // Execute modules who's dependencies have just been met
 482                                 for ( r in registry ) {
 483                                         if ( registry[r].state == 'loaded' ) {
 484                                                 if ( compare( filter( ['ready'], registry[r].dependencies ), registry[r].dependencies ) ) {
 485                                                         execute( r );
 486                                                 }
 487                                         }
 488                                 }
 489                         } catch ( e ) {
 490                                 mediaWiki.log( 'Exception thrown by ' + module + ': ' + e.message );
 491                                 mediaWiki.log( e );
 492                                 registry[module].state = 'error';
 493                                 // Run error callbacks of jobs affected by this condition
 494                                 for ( var j = 0; j < jobs.length; j++ ) {
 495                                         if ( $.inArray( module, jobs[j].dependencies ) !== -1 ) {
 496                                                 if ( typeof jobs[j].error === 'function' ) {
 497                                                         jobs[j].error();
 498                                                 }
 499                                                 jobs.splice( j, 1 );
 500                                                 j--;
 501                                         }
 502                                 }
 503                         }
 504                 }
 505
 506                 /**
 507                  * Adds a dependencies to the queue with optional callbacks to be run when the dependencies are ready or fail
 508                  *
 509                  * @param mixed string moulde name or array of string module names
 510                  * @param function ready callback to execute when all dependencies are ready
 511                  * @param function error callback to execute when any dependency fails
 512                  */
 513                 function request( dependencies, ready, error ) {
 514                         // Allow calling by single module name
 515                         if ( typeof dependencies === 'string' ) {
 516                                 dependencies = [dependencies];
 517                                 if ( dependencies[0] in registry ) {
 518                                         for ( var n = 0; n < registry[dependencies[0]].dependencies.length; n++ ) {
 519                                                 dependencies[dependencies.length] = registry[dependencies[0]].dependencies[n];
 520                                         }
 521                                 }
 522                         }
 523                         // Add ready and error callbacks if they were given
 524                         if ( arguments.length > 1 ) {
 525                                 jobs[jobs.length] = {
 526                                         'dependencies': filter( ['undefined', 'registered', 'loading', 'loaded'], dependencies ),
 527                                         'ready': ready,
 528                                         'error': error
 529                                 };
 530                         }
 531                         // Queue up any dependencies that are undefined or registered
 532                         dependencies = filter( ['undefined', 'registered'], dependencies );
 533                         for ( var n = 0; n < dependencies.length; n++ ) {
 534                                 if ( $.inArray( dependencies[n], queue ) === -1 ) {
 535                                         queue[queue.length] = dependencies[n];
 536                                 }
 537                         }
 538                         // Work the queue
 539                         mediaWiki.loader.work();
 540                 }
 541
 542                 function sortQuery(o) {
 543                         var sorted = {}, key, a = [];
 544                         for ( key in o ) {
 545                                 if ( o.hasOwnProperty( key ) ) {
 546                                         a.push( key );
 547                                 }
 548                         }
 549                         a.sort();
 550                         for ( key = 0; key < a.length; key++ ) {
 551                                 sorted[a[key]] = o[a[key]];
 552                         }
 553                         return sorted;
 554                 }
 555
 556                 /* Public Methods */
 557
 558                 /**
 559                  * Requests dependencies from server, loading and executing when things when ready.
 560                  */
 561                 this.work = function() {
 562                         // Appends a list of modules to the batch
 563                         for ( var q = 0; q < queue.length; q++ ) {
 564                                 // Only request modules which are undefined or registered
 565                                 if ( !( queue[q] in registry ) || registry[queue[q]].state == 'registered' ) {
 566                                         // Prevent duplicate entries
 567                                         if ( $.inArray( queue[q], batch ) === -1 ) {
 568                                                 batch[batch.length] = queue[q];
 569                                                 // Mark registered modules as loading
 570                                                 if ( queue[q] in registry ) {
 571                                                         registry[queue[q]].state = 'loading';
 572                                                 }
 573                                         }
 574                                 }
 575                         }
 576                         // Clean up the queue
 577                         queue = [];
 578                         // After document ready, handle the batch
 579                         if ( !suspended && batch.length ) {
 580                                 // Always order modules alphabetically to help reduce cache misses for otherwise identical content
 581                                 batch.sort();
 582                                 // Build a list of request parameters
 583                                 var base = {
 584                                         'skin': mediaWiki.config.get( 'skin' ),
 585                                         'lang': mediaWiki.config.get( 'wgUserLanguage' ),
 586                                         'debug': mediaWiki.config.get( 'debug' )
 587                                 };
 588                                 // Extend request parameters with a list of modules in the batch
 589                                 var requests = [];
 590                                 // Split into groups
 591                                 var groups = {};
 592                                 for ( var b = 0; b < batch.length; b++ ) {
 593                                         var group = registry[batch[b]].group;
 594                                         if ( !( group in groups ) ) {
 595                                                 groups[group] = [];
 596                                         }
 597                                         groups[group][groups[group].length] = batch[b];
 598                                 }
 599                                 for ( var group in groups ) {
 600                                         // Calculate the highest timestamp
 601                                         var version = 0;
 602                                         for ( var g = 0; g < groups[group].length; g++ ) {
 603                                                 if ( registry[groups[group][g]].version > version ) {
 604                                                         version = registry[groups[group][g]].version;
 605                                                 }
 606                                         }
 607                                         requests[requests.length] = $.extend(
 608                                                 { 'modules': groups[group].join( '|' ), 'version': formatVersionNumber( version ) }, base
 609                                         );
 610                                 }
 611                                 // Clear the batch - this MUST happen before we append the script element to the body or it's
 612                                 // possible that the script will be locally cached, instantly load, and work the batch again,
 613                                 // all before we've cleared it causing each request to include modules which are already loaded
 614                                 batch = [];
 615                                 // Asynchronously append a script tag to the end of the body
 616                                 function request() {
 617                                         var html = '';
 618                                         for ( var r = 0; r < requests.length; r++ ) {
 619                                                 requests[r] = sortQuery( requests[r] );
 620                                                 // Build out the HTML
 621                                                 var src = mediaWiki.config.get( 'wgLoadScript' ) + '?' + $.param( requests[r] );
 622                                                 html += '<script type="text/javascript" src="' + src + '"></script>';
 623                                         }
 624                                         return html;
 625                                 }
 626                                 // Load asynchronously after doumument ready
 627                                 if ( ready ) {
 628                                         setTimeout( function() { $( 'body' ).append( request() ); }, 0 )
 629                                 } else {
 630                                         document.write( request() );
 631                                 }
 632                         }
 633                 };
 634
 635                 /**
 636                  * Registers a module, letting the system know about it and it's dependencies. loader.js files contain calls
 637                  * to this function.
 638                  */
 639                 this.register = function( module, version, dependencies, group ) {
 640                         // Allow multiple registration
 641                         if ( typeof module === 'object' ) {
 642                                 for ( var m = 0; m < module.length; m++ ) {
 643                                         if ( typeof module[m] === 'string' ) {
 644                                                 mediaWiki.loader.register( module[m] );
 645                                         } else if ( typeof module[m] === 'object' ) {
 646                                                 mediaWiki.loader.register.apply( mediaWiki.loader, module[m] );
 647                                         }
 648                                 }
 649                                 return;
 650                         }
 651                         // Validate input
 652                         if ( typeof module !== 'string' ) {
 653                                 throw new Error( 'module must be a string, not a ' + typeof module );
 654                         }
 655                         if ( typeof registry[module] !== 'undefined' ) {
 656                                 throw new Error( 'module already implemeneted: ' + module );
 657                         }
 658                         // List the module as registered
 659                         registry[module] = {
 660                                 'state': 'registered',
 661                                 'group': typeof group === 'string' ? group : null,
 662                                 'dependencies': [],
 663                                 'version': typeof version !== 'undefined' ? parseInt( version ) : 0
 664                         };
 665                         if ( typeof dependencies === 'string' ) {
 666                                 // Allow dependencies to be given as a single module name
 667                                 registry[module].dependencies = [dependencies];
 668                         } else if ( typeof dependencies === 'object' || typeof dependencies === 'function' ) {
 669                                 // Allow dependencies to be given as an array of module names or a function which returns an array
 670                                 registry[module].dependencies = dependencies;
 671                         }
 672                 };
 673
 674                 /**
 675                  * Implements a module, giving the system a course of action to take upon loading. Results of a request for
 676                  * one or more modules contain calls to this function.
 677                  */
 678                 this.implement = function( module, script, style, localization ) {
 679                         // Automaically register module
 680                         if ( typeof registry[module] === 'undefined' ) {
 681                                 mediaWiki.loader.register( module );
 682                         }
 683                         // Validate input
 684                         if ( typeof script !== 'function' ) {
 685                                 throw new Error( 'script must be a function, not a ' + typeof script );
 686                         }
 687                         if ( typeof style !== 'undefined' && typeof style !== 'string' && typeof style !== 'object' ) {
 688                                 throw new Error( 'style must be a string or object, not a ' + typeof style );
 689                         }
 690                         if ( typeof localization !== 'undefined' && typeof localization !== 'object' ) {
 691                                 throw new Error( 'localization must be an object, not a ' + typeof localization );
 692                         }
 693                         if ( typeof registry[module] !== 'undefined' && typeof registry[module].script !== 'undefined' ) {
 694                                 throw new Error( 'module already implemeneted: ' + module );
 695                         }
 696                         // Mark module as loaded
 697                         registry[module].state = 'loaded';
 698                         // Attach components
 699                         registry[module].script = script;
 700                         if ( typeof style === 'string' || typeof style === 'object' && !( style instanceof Array ) ) {
 701                                 registry[module].style = style;
 702                         }
 703                         if ( typeof localization === 'object' ) {
 704                                 registry[module].messages = localization;
 705                         }
 706                         // Execute or queue callback
 707                         if ( compare( filter( ['ready'], registry[module].dependencies ), registry[module].dependencies ) ) {
 708                                 execute( module );
 709                         } else {
 710                                 request( module );
 711                         }
 712                 };
 713
 714                 /**
 715                  * Executes a function as soon as one or more required modules are ready
 716                  *
 717                  * @param mixed string or array of strings of modules names the callback dependencies to be ready before
 718                  * executing
 719                  * @param function callback to execute when all dependencies are ready (optional)
 720                  * @param function callback to execute when if dependencies have a errors (optional)
 721                  */
 722                 this.using = function( dependencies, ready, error ) {
 723                         // Validate input
 724                         if ( typeof dependencies !== 'object' && typeof dependencies !== 'string' ) {
 725                                 throw new Error( 'dependencies must be a string or an array, not a ' + typeof dependencies )
 726                         }
 727                         // Allow calling with a single dependency as a string
 728                         if ( typeof dependencies === 'string' ) {
 729                                 dependencies = [dependencies];
 730                         }
 731                         // Resolve entire dependency map
 732                         dependencies = resolve( dependencies );
 733                         // If all dependencies are met, execute ready immediately
 734                         if ( compare( filter( ['ready'], dependencies ), dependencies ) ) {
 735                                 if ( typeof ready === 'function' ) {
 736                                         ready();
 737                                 }
 738                         }
 739                         // If any dependencies have errors execute error immediately
 740                         else if ( filter( ['error'], dependencies ).length ) {
 741                                 if ( typeof error === 'function' ) {
 742                                         error();
 743                                 }
 744                         }
 745                         // Since some dependencies are not yet ready, queue up a request
 746                         else {
 747                                 request( dependencies, ready, error );
 748                         }
 749                 };
 750
 751                 /**
 752                  * Loads an external script or one or more modules for future use
 753                  *
 754                  * @param {mixed} modules either the name of a module, array of modules, or a URL of an external script or style
 755                  * @param {string} type mime-type to use if calling with a URL of an external script or style; acceptable values
 756                  * are "text/css" and "text/javascript"; if no type is provided, text/javascript is assumed
 757                  */
 758                 this.load = function( modules, type ) {
 759                         // Validate input
 760                         if ( typeof modules !== 'object' && typeof modules !== 'string' ) {
 761                                 throw new Error( 'dependencies must be a string or an array, not a ' + typeof dependencies )
 762                         }
 763                         // Allow calling with an external script or single dependency as a string
 764                         if ( typeof modules === 'string' ) {
 765                                 // Support adding arbitrary external scripts
 766                                 if ( modules.substr( 0, 7 ) == 'http://' || modules.substr( 0, 8 ) == 'https://' ) {
 767                                         if ( type === 'text/css' ) {
 768                                                 $( 'head' ).append( $( '<link rel="stylesheet" type="text/css" />' ).attr( 'href', modules ) );
 769                                                 return true;
 770                                         } else if ( type === 'text/javascript' || typeof type === 'undefined' ) {
 771                                                 var script = '<script type="text/javascript" src="' + modules + '"></script>';
 772                                                 if ( ready ) {
 773                                                         $( 'body' ).append( script );
 774                                                 } else {
 775                                                         document.write( script );
 776                                                 }
 777                                                 return true;
 778                                         }
 779                                         // Unknown type
 780                                         return false;
 781                                 }
 782                                 // Called with single module
 783                                 modules = [modules];
 784                         }
 785                         // Resolve entire dependency map
 786                         modules = resolve( modules );
 787                         // If all modules are ready, nothing dependency be done
 788                         if ( compare( filter( ['ready'], modules ), modules ) ) {
 789                                 return true;
 790                         }
 791                         // If any modules have errors return false
 792                         else if ( filter( ['error'], modules ).length ) {
 793                                 return false;
 794                         }
 795                         // Since some modules are not yet ready, queue up a request
 796                         else {
 797                                 request( modules );
 798                                 return true;
 799                         }
 800                 };
 801
 802                 /**
 803                  * Flushes the request queue and begin executing load requests on demand
 804                  */
 805                 this.go = function() {
 806                         suspended = false;
 807                         mediaWiki.loader.work();
 808                 };
 809
 810                 /**
 811                  * Changes the state of a module
 812                  *
 813                  * @param mixed module string module name or object of module name/state pairs
 814                  * @param string state string state name
 815                  */
 816                 this.state = function( module, state ) {
 817                         if ( typeof module === 'object' ) {
 818                                 for ( var m in module ) {
 819                                         mediaWiki.loader.state( m, module[m] );
 820                                 }
 821                                 return;
 822                         }
 823                         if ( !( module in registry ) ) {
 824                                 mediaWiki.loader.register( module );
 825                         }
 826                         registry[module].state = state;
 827                 };
 828
 829                 /**
 830                  * Gets the version of a module
 831                  *
 832                  * @param string module name of module to get version for
 833                  */
 834                 this.version = function( module ) {
 835                         if ( module in registry && 'version' in registry[module] ) {
 836                                 return formatVersionNumber( registry[module].version );
 837                         }
 838                         return null;
 839                 }
 840
 841                 /* Cache document ready status */
 842
 843                 $(document).ready( function() { ready = true; } );
 844         } )();
 845
 846         /* Extension points */
 847
 848         this.legacy = {};
 849
 850 } )( jQuery );
 851
 852 /* Auto-register from pre-loaded startup scripts */
 853
 854 if ( typeof startUp === 'function' ) {
 855         startUp();
 856         delete startUp;
 857 }
 858
 859 // Alias $j to jQuery for backwards compatibility
 860 window.$j = jQuery;
 861 window.mw = mediaWiki;