includes/SpecialPage.php

   1 <?php
   2 /**
   3  * SpecialPage: handling special pages and lists thereof.
   4  *
   5  * To add a special page in an extension, add to $wgSpecialPages either
   6  * an object instance or an array containing the name and constructor
   7  * parameters. The latter is preferred for performance reasons.
   8  *
   9  * The object instantiated must be either an instance of SpecialPage or a
  10  * sub-class thereof. It must have an execute() method, which sends the HTML
  11  * for the special page to $wgOut. The parent class has an execute() method
  12  * which distributes the call to the historical global functions. Additionally,
  13  * execute() also checks if the user has the necessary access privileges
  14  * and bails out if not.
  15  *
  16  * To add a core special page, use the similar static list in
  17  * SpecialPage::$mList. To remove a core static special page at runtime, use
  18  * a SpecialPage_initList hook.
  19  *
  20  * @file
  21  * @ingroup SpecialPage
  22  * @defgroup SpecialPage SpecialPage
  23  */
  24
  25 /**
  26  * Parent special page class, also static functions for handling the special
  27  * page list.
  28  * @ingroup SpecialPage
  29  */
  30 class SpecialPage {
  31
  32         // The canonical name of this special page
  33         // Also used for the default <h1> heading, @see getDescription()
  34         protected $mName;
  35
  36         // The local name of this special page
  37         private $mLocalName;
  38
  39         // Minimum user level required to access this page, or "" for anyone.
  40         // Also used to categorise the pages in Special:Specialpages
  41         private $mRestriction;
  42
  43         // Listed in Special:Specialpages?
  44         private $mListed;
  45
  46         // Function name called by the default execute()
  47         private $mFunction;
  48
  49         // File which needs to be included before the function above can be called
  50         private $mFile;
  51
  52         // Whether or not this special page is being included from an article
  53         protected $mIncluding;
  54
  55         // Whether the special page can be included in an article
  56         protected $mIncludable;
  57
  58         /**
  59          * Current request context
  60          * @var IContextSource
  61          */
  62         protected $mContext;
  63
  64         /**
  65          * Initialise the special page list
  66          * This must be called before accessing SpecialPage::$mList
  67          * @deprecated since 1.18
  68          */
  69         static function initList() {
  70                 // Noop
  71         }
  72
  73         /**
  74          * @deprecated since 1.18
  75          */
  76         static function initAliasList() {
  77                 // Noop
  78         }
  79
  80         /**
  81          * Given a special page alias, return the special page name.
  82          * Returns false if there is no such alias.
  83          *
  84          * @param $alias String
  85          * @return String or false
  86          * @deprecated since 1.18 call SpecialPageFactory method directly
  87          */
  88         static function resolveAlias( $alias ) {
  89                 list( $name, /*...*/ ) = SpecialPageFactory::resolveAlias( $alias );
  90                 return $name;
  91         }
  92
  93         /**
  94          * Given a special page name with a possible subpage, return an array
  95          * where the first element is the special page name and the second is the
  96          * subpage.
  97          *
  98          * @param $alias String
  99          * @return Array
 100          * @deprecated since 1.18 call SpecialPageFactory method directly
 101          */
 102         static function resolveAliasWithSubpage( $alias ) {
 103                 return SpecialPageFactory::resolveAlias( $alias );
 104         }
 105
 106         /**
 107          * Add a page to the list of valid special pages. This used to be the preferred
 108          * method for adding special pages in extensions. It's now suggested that you add
 109          * an associative record to $wgSpecialPages. This avoids autoloading SpecialPage.
 110          *
 111          * @param $page SpecialPage
 112          * @deprecated since 1.7, warnings in 1.17, might be removed in 1.20
 113          */
 114         static function addPage( &$page ) {
 115                 wfDeprecated( __METHOD__ );
 116                 SpecialPageFactory::getList()->{$page->mName} = $page;
 117         }
 118
 119         /**
 120          * Add a page to a certain display group for Special:SpecialPages
 121          *
 122          * @param $page Mixed: SpecialPage or string
 123          * @param $group String
 124          * @return null
 125          * @deprecated since 1.18 call SpecialPageFactory method directly
 126          */
 127         static function setGroup( $page, $group ) {
 128                 return SpecialPageFactory::setGroup( $page, $group );
 129         }
 130
 131         /**
 132          * Get the group that the special page belongs in on Special:SpecialPage
 133          *
 134          * @param $page SpecialPage
 135          * @return null
 136          * @deprecated since 1.18 call SpecialPageFactory method directly
 137          */
 138         static function getGroup( &$page ) {
 139                 return SpecialPageFactory::getGroup( $page );
 140         }
 141
 142         /**
 143          * Remove a special page from the list
 144          * Formerly used to disable expensive or dangerous special pages. The
 145          * preferred method is now to add a SpecialPage_initList hook.
 146          * @deprecated since 1.18
 147          *
 148          * @param $name String the page to remove
 149          */
 150         static function removePage( $name ) {
 151                 unset( SpecialPageFactory::getList()->$name );
 152         }
 153
 154         /**
 155          * Check if a given name exist as a special page or as a special page alias
 156          *
 157          * @param $name String: name of a special page
 158          * @return Boolean: true if a special page exists with this name
 159          * @deprecated since 1.18 call SpecialPageFactory method directly
 160          */
 161         static function exists( $name ) {
 162                 return SpecialPageFactory::exists( $name );
 163         }
 164
 165         /**
 166          * Find the object with a given name and return it (or NULL)
 167          *
 168          * @param $name String
 169          * @return SpecialPage object or null if the page doesn't exist
 170          * @deprecated since 1.18 call SpecialPageFactory method directly
 171          */
 172         static function getPage( $name ) {
 173                 return SpecialPageFactory::getPage( $name );
 174         }
 175
 176         /**
 177          * Get a special page with a given localised name, or NULL if there
 178          * is no such special page.
 179          *
 180          * @param $alias String
 181          * @return SpecialPage object or null if the page doesn't exist
 182          * @deprecated since 1.18 call SpecialPageFactory method directly
 183          */
 184         static function getPageByAlias( $alias ) {
 185                 return SpecialPageFactory::getPage( $alias );
 186         }
 187
 188         /**
 189          * Return categorised listable special pages which are available
 190          * for the current user, and everyone.
 191          *
 192          * @param $user User object to check permissions, $wgUser will be used
 193          *              if not provided
 194          * @return Associative array mapping page's name to its SpecialPage object
 195          * @deprecated since 1.18 call SpecialPageFactory method directly
 196          */
 197         static function getUsablePages( User $user = null ) {
 198                 return SpecialPageFactory::getUsablePages( $user );
 199         }
 200
 201         /**
 202          * Return categorised listable special pages for all users
 203          *
 204          * @return Associative array mapping page's name to its SpecialPage object
 205          * @deprecated since 1.18 call SpecialPageFactory method directly
 206          */
 207         static function getRegularPages() {
 208                 return SpecialPageFactory::getRegularPages();
 209         }
 210
 211         /**
 212          * Return categorised listable special pages which are available
 213          * for the current user, but not for everyone
 214          *
 215          * @return Associative array mapping page's name to its SpecialPage object
 216          * @deprecated since 1.18 call SpecialPageFactory method directly
 217          */
 218         static function getRestrictedPages() {
 219                 return SpecialPageFactory::getRestrictedPages();
 220         }
 221
 222         /**
 223          * Execute a special page path.
 224          * The path may contain parameters, e.g. Special:Name/Params
 225          * Extracts the special page name and call the execute method, passing the parameters
 226          *
 227          * Returns a title object if the page is redirected, false if there was no such special
 228          * page, and true if it was successful.
 229          *
 230          * @param $title          Title object
 231          * @param $context        IContextSource
 232          * @param $including      Bool output is being captured for use in {{special:whatever}}
 233          * @return Bool
 234          * @deprecated since 1.18 call SpecialPageFactory method directly
 235          */
 236         public static function executePath( &$title, IContextSource &$context, $including = false ) {
 237                 return SpecialPageFactory::executePath( $title, $context, $including );
 238         }
 239
 240         /**
 241          * Get the local name for a specified canonical name
 242          *
 243          * @param $name String
 244          * @param $subpage Mixed: boolean false, or string
 245          *
 246          * @return String
 247          * @deprecated since 1.18 call SpecialPageFactory method directly
 248          */
 249         static function getLocalNameFor( $name, $subpage = false ) {
 250                 return SpecialPageFactory::getLocalNameFor( $name, $subpage );
 251         }
 252
 253         /**
 254          * Get a localised Title object for a specified special page name
 255          *
 256          * @param $name String
 257          * @param $subpage String|Bool subpage string, or false to not use a subpage
 258          * @return Title object
 259          */
 260         public static function getTitleFor( $name, $subpage = false ) {
 261                 $name = SpecialPageFactory::getLocalNameFor( $name, $subpage );
 262                 if ( $name ) {
 263                         return Title::makeTitle( NS_SPECIAL, $name );
 264                 } else {
 265                         throw new MWException( "Invalid special page name \"$name\"" );
 266                 }
 267         }
 268
 269         /**
 270          * Get a localised Title object for a page name with a possibly unvalidated subpage
 271          *
 272          * @param $name String
 273          * @param $subpage String|Bool subpage string, or false to not use a subpage
 274          * @return Title object or null if the page doesn't exist
 275          */
 276         public static function getSafeTitleFor( $name, $subpage = false ) {
 277                 $name = SpecialPageFactory::getLocalNameFor( $name, $subpage );
 278                 if ( $name ) {
 279                         return Title::makeTitleSafe( NS_SPECIAL, $name );
 280                 } else {
 281                         return null;
 282                 }
 283         }
 284
 285         /**
 286          * Get a title for a given alias
 287          *
 288          * @param $alias String
 289          * @return Title or null if there is no such alias
 290          * @deprecated since 1.18 call SpecialPageFactory method directly
 291          */
 292         static function getTitleForAlias( $alias ) {
 293                 return SpecialPageFactory::getTitleForAlias( $alias );
 294         }
 295
 296         /**
 297          * Default constructor for special pages
 298          * Derivative classes should call this from their constructor
 299          *     Note that if the user does not have the required level, an error message will
 300          *     be displayed by the default execute() method, without the global function ever
 301          *     being called.
 302          *
 303          *     If you override execute(), you can recover the default behaviour with userCanExecute()
 304          *     and displayRestrictionError()
 305          *
 306          * @param $name String: name of the special page, as seen in links and URLs
 307          * @param $restriction String: user right required, e.g. "block" or "delete"
 308          * @param $listed Bool: whether the page is listed in Special:Specialpages
 309          * @param $function Callback|Bool: function called by execute(). By default it is constructed from $name
 310          * @param $file String: file which is included by execute(). It is also constructed from $name by default
 311          * @param $includable Bool: whether the page can be included in normal pages
 312          */
 313         public function __construct(
 314                 $name = '', $restriction = '', $listed = true,
 315                 $function = false, $file = 'default', $includable = false
 316         ) {
 317                 $this->init( $name, $restriction, $listed, $function, $file, $includable );
 318         }
 319
 320         /**
 321          * Do the real work for the constructor, mainly so __call() can intercept
 322          * calls to SpecialPage()
 323          * @param $name String: name of the special page, as seen in links and URLs
 324          * @param $restriction String: user right required, e.g. "block" or "delete"
 325          * @param $listed Bool: whether the page is listed in Special:Specialpages
 326          * @param $function Callback|Bool: function called by execute(). By default it is constructed from $name
 327          * @param $file String: file which is included by execute(). It is also constructed from $name by default
 328          * @param $includable Bool: whether the page can be included in normal pages
 329          */
 330         private function init( $name, $restriction, $listed, $function, $file, $includable ) {
 331                 $this->mName = $name;
 332                 $this->mRestriction = $restriction;
 333                 $this->mListed = $listed;
 334                 $this->mIncludable = $includable;
 335                 if ( !$function ) {
 336                         $this->mFunction = 'wfSpecial'.$name;
 337                 } else {
 338                         $this->mFunction = $function;
 339                 }
 340                 if ( $file === 'default' ) {
 341                         $this->mFile = dirname(__FILE__) . "/specials/Special$name.php";
 342                 } else {
 343                         $this->mFile = $file;
 344                 }
 345         }
 346
 347         /**
 348          * Use PHP's magic __call handler to get calls to the old PHP4 constructor
 349          * because PHP E_STRICT yells at you for having __construct() and SpecialPage()
 350          *
 351          * @param $fName String Name of called method
 352          * @param $a Array Arguments to the method
 353          * @deprecated since 1.17, call parent::__construct()
 354          */
 355         public function __call( $fName, $a ) {
 356                 // Sometimes $fName is SpecialPage, sometimes it's specialpage. <3 PHP
 357                 if( strtolower( $fName ) == 'specialpage' ) {
 358                         // Deprecated messages now, remove in 1.19 or 1.20?
 359                         wfDeprecated( __METHOD__ );
 360
 361                         $name = isset( $a[0] ) ? $a[0] : '';
 362                         $restriction = isset( $a[1] ) ? $a[1] : '';
 363                         $listed = isset( $a[2] ) ? $a[2] : true;
 364                         $function = isset( $a[3] ) ? $a[3] : false;
 365                         $file = isset( $a[4] ) ? $a[4] : 'default';
 366                         $includable = isset( $a[5] ) ? $a[5] : false;
 367                         $this->init( $name, $restriction, $listed, $function, $file, $includable );
 368                 } else {
 369                         $className = get_class( $this );
 370                         throw new MWException( "Call to undefined method $className::$fName" );
 371                 }
 372         }
 373
 374         /**
 375          * Get the name of this Special Page.
 376          * @return String
 377          */
 378         function getName() {
 379                 return $this->mName;
 380         }
 381
 382         /**
 383          * Get the permission that a user must have to execute this page
 384          * @return String
 385          */
 386         function getRestriction() {
 387                 return $this->mRestriction;
 388         }
 389
 390         /**
 391          * Get the file which will be included by SpecialPage::execute() if your extension is
 392          * still stuck in the past and hasn't overridden the execute() method.  No modern code
 393          * should want or need to know this.
 394          * @return String
 395          * @deprecated since 1.18
 396          */
 397         function getFile() {
 398                 return $this->mFile;
 399         }
 400
 401         // @todo FIXME: Decide which syntax to use for this, and stick to it
 402         /**
 403          * Whether this special page is listed in Special:SpecialPages
 404          * @since r3583 (v1.3)
 405          * @return Bool
 406          */
 407         function isListed() {
 408                 return $this->mListed;
 409         }
 410         /**
 411          * Set whether this page is listed in Special:Specialpages, at run-time
 412          * @since r3583 (v1.3)
 413          * @param $listed Bool
 414          * @return Bool
 415          */
 416         function setListed( $listed ) {
 417                 return wfSetVar( $this->mListed, $listed );
 418         }
 419         /**
 420          * Get or set whether this special page is listed in Special:SpecialPages
 421          * @since r11308 (v1.6)
 422          * @param $x Bool
 423          * @return Bool
 424          */
 425         function listed( $x = null) {
 426                 return wfSetVar( $this->mListed, $x );
 427         }
 428
 429         /**
 430          * Whether it's allowed to transclude the special page via {{Special:Foo/params}}
 431          * @return Bool
 432          */
 433         public function isIncludable(){
 434                 return $this->mIncludable;
 435         }
 436
 437         /**
 438          * These mutators are very evil, as the relevant variables should not mutate.  So
 439          * don't use them.
 440          * @param $x Mixed
 441          * @return Mixed
 442          * @deprecated since 1.18
 443          */
 444         function name( $x = null ) { return wfSetVar( $this->mName, $x ); }
 445         function restriction( $x = null) { return wfSetVar( $this->mRestriction, $x ); }
 446         function func( $x = null) { return wfSetVar( $this->mFunction, $x ); }
 447         function file( $x = null) { return wfSetVar( $this->mFile, $x ); }
 448         function includable( $x = null ) { return wfSetVar( $this->mIncludable, $x ); }
 449
 450         /**
 451          * Whether the special page is being evaluated via transclusion
 452          * @param $x Bool
 453          * @return Bool
 454          */
 455         function including( $x = null ) {
 456                 return wfSetVar( $this->mIncluding, $x );
 457         }
 458
 459         /**
 460          * Get the localised name of the special page
 461          */
 462         function getLocalName() {
 463                 if ( !isset( $this->mLocalName ) ) {
 464                         $this->mLocalName = SpecialPageFactory::getLocalNameFor( $this->mName );
 465                 }
 466                 return $this->mLocalName;
 467         }
 468
 469         /**
 470          * Is this page expensive (for some definition of expensive)?
 471          * Expensive pages are disabled or cached in miser mode.  Originally used
 472          * (and still overridden) by QueryPage and subclasses, moved here so that
 473          * Special:SpecialPages can safely call it for all special pages.
 474          *
 475          * @return Boolean
 476          */
 477         public function isExpensive() {
 478                 return false;
 479         }
 480
 481         /**
 482          * Can be overridden by subclasses with more complicated permissions
 483          * schemes.
 484          *
 485          * @return Boolean: should the page be displayed with the restricted-access
 486          *   pages?
 487          */
 488         public function isRestricted() {
 489                 global $wgGroupPermissions;
 490                 // DWIM: If all anons can do something, then it is not restricted
 491                 return $this->mRestriction != '' && empty($wgGroupPermissions['*'][$this->mRestriction]);
 492         }
 493
 494         /**
 495          * Checks if the given user (identified by an object) can execute this
 496          * special page (as defined by $mRestriction).  Can be overridden by sub-
 497          * classes with more complicated permissions schemes.
 498          *
 499          * @param $user User: the user to check
 500          * @return Boolean: does the user have permission to view the page?
 501          */
 502         public function userCanExecute( User $user ) {
 503                 return $user->isAllowed( $this->mRestriction );
 504         }
 505
 506         /**
 507          * Output an error message telling the user what access level they have to have
 508          */
 509         function displayRestrictionError() {
 510                 throw new PermissionsError( $this->mRestriction );
 511         }
 512
 513         /**
 514          * Sets headers - this should be called from the execute() method of all derived classes!
 515          */
 516         function setHeaders() {
 517                 $out = $this->getOutput();
 518                 $out->setArticleRelated( false );
 519                 $out->setRobotPolicy( "noindex,nofollow" );
 520                 $out->setPageTitle( $this->getDescription() );
 521         }
 522
 523         /**
 524          * Default execute method
 525          * Checks user permissions, calls the function given in mFunction
 526          *
 527          * This must be overridden by subclasses; it will be made abstract in a future version
 528          *
 529          * @param $par String subpage string, if one was specified
 530          */
 531         function execute( $par ) {
 532                 $this->setHeaders();
 533
 534                 if ( $this->userCanExecute( $this->getUser() ) ) {
 535                         $func = $this->mFunction;
 536                         // only load file if the function does not exist
 537                         if( !is_callable($func) && $this->mFile ) {
 538                                 require_once( $this->mFile );
 539                         }
 540                         $this->outputHeader();
 541                         call_user_func( $func, $par, $this );
 542                 } else {
 543                         $this->displayRestrictionError();
 544                 }
 545         }
 546
 547         /**
 548          * Outputs a summary message on top of special pages
 549          * Per default the message key is the canonical name of the special page
 550          * May be overriden, i.e. by extensions to stick with the naming conventions
 551          * for message keys: 'extensionname-xxx'
 552          *
 553          * @param $summaryMessageKey String: message key of the summary
 554          */
 555         function outputHeader( $summaryMessageKey = '' ) {
 556                 global $wgContLang;
 557
 558                 if( $summaryMessageKey == '' ) {
 559                         $msg = $wgContLang->lc( $this->getName() ) . '-summary';
 560                 } else {
 561                         $msg = $summaryMessageKey;
 562                 }
 563                 if ( !$this->msg( $msg )->isBlank() && !$this->including() ) {
 564                         $this->getOutput()->wrapWikiMsg(
 565                                 "<div class='mw-specialpage-summary'>\n$1\n</div>", $msg );
 566                 }
 567
 568         }
 569
 570         /**
 571          * Returns the name that goes in the \<h1\> in the special page itself, and
 572          * also the name that will be listed in Special:Specialpages
 573          *
 574          * Derived classes can override this, but usually it is easier to keep the
 575          * default behaviour. Messages can be added at run-time, see
 576          * MessageCache.php.
 577          *
 578          * @return String
 579          */
 580         function getDescription() {
 581                 return $this->msg( strtolower( $this->mName ) )->text();
 582         }
 583
 584         /**
 585          * Get a self-referential title object
 586          *
 587          * @param $subpage String|Bool
 588          * @return Title object
 589          */
 590         function getTitle( $subpage = false ) {
 591                 return self::getTitleFor( $this->mName, $subpage );
 592         }
 593
 594         /**
 595          * Sets the context this SpecialPage is executed in
 596          *
 597          * @param $context IContextSource
 598          * @since 1.18
 599          */
 600         public function setContext( $context ) {
 601                 $this->mContext = $context;
 602         }
 603
 604         /**
 605          * Gets the context this SpecialPage is executed in
 606          *
 607          * @return IContextSource
 608          * @since 1.18
 609          */
 610         public function getContext() {
 611                 if ( $this->mContext instanceof IContextSource ) {
 612                         return $this->mContext;
 613                 } else {
 614                         wfDebug( __METHOD__ . " called and \$mContext is null. Return RequestContext::getMain(); for sanity\n" );
 615                         return RequestContext::getMain();
 616                 }
 617         }
 618
 619         /**
 620          * Get the WebRequest being used for this instance
 621          *
 622          * @return WebRequest
 623          * @since 1.18
 624          */
 625         public function getRequest() {
 626                 return $this->getContext()->getRequest();
 627         }
 628
 629         /**
 630          * Get the OutputPage being used for this instance
 631          *
 632          * @return OutputPage
 633          * @since 1.18
 634          */
 635         public function getOutput() {
 636                 return $this->getContext()->getOutput();
 637         }
 638
 639         /**
 640          * Shortcut to get the User executing this instance
 641          *
 642          * @return User
 643          * @since 1.18
 644          */
 645         public function getUser() {
 646                 return $this->getContext()->getUser();
 647         }
 648
 649         /**
 650          * Shortcut to get the skin being used for this instance
 651          *
 652          * @return Skin
 653          * @since 1.18
 654          */
 655         public function getSkin() {
 656                 return $this->getContext()->getSkin();
 657         }
 658
 659         /**
 660          * Shortcut to get user's language
 661          *
 662          * @return Language
 663          * @since 1.18
 664          */
 665         public function getLang() {
 666                 return $this->getContext()->getLang();
 667         }
 668
 669         /**
 670          * Return the full title, including $par
 671          *
 672          * @return Title
 673          * @since 1.18
 674          */
 675         public function getFullTitle() {
 676                 return $this->getContext()->getTitle();
 677         }
 678
 679         /**
 680          * Wrapper around wfMessage that sets the current context.
 681          *
 682          * @return Message
 683          * @see wfMessage
 684          */
 685         public function msg( /* $args */ ) {
 686                 // Note: can't use func_get_args() directly as second or later item in
 687                 // a parameter list until PHP 5.3 or you get a fatal error.
 688                 // Works fine as the first parameter, which appears elsewhere in the
 689                 // code base. Sighhhh.
 690                 $args = func_get_args();
 691                 return call_user_func_array( array( $this->getContext(), 'msg' ), $args );
 692         }
 693
 694         /**
 695          * Adds RSS/atom links
 696          *
 697          * @param $params array
 698          */
 699         protected function addFeedLinks( $params ) {
 700                 global $wgFeedClasses;
 701
 702                 $feedTemplate = wfScript( 'api' ) . '?';
 703
 704                 foreach( $wgFeedClasses as $format => $class ) {
 705                         $theseParams = $params + array( 'feedformat' => $format );
 706                         $url = $feedTemplate . wfArrayToCGI( $theseParams );
 707                         $this->getOutput()->addFeedLink( $format, $url );
 708                 }
 709         }
 710 }
 711
 712 /**
 713  * Special page which uses an HTMLForm to handle processing.  This is mostly a
 714  * clone of FormAction.  More special pages should be built this way; maybe this could be
 715  * a new structure for SpecialPages
 716  */
 717 abstract class FormSpecialPage extends SpecialPage {
 718
 719         /**
 720          * Get an HTMLForm descriptor array
 721          * @return Array
 722          */
 723         protected abstract function getFormFields();
 724
 725         /**
 726          * Add pre- or post-text to the form
 727          * @return String HTML which will be sent to $form->addPreText()
 728          */
 729         protected function preText() { return ''; }
 730         protected function postText() { return ''; }
 731
 732         /**
 733          * Play with the HTMLForm if you need to more substantially
 734          * @param $form HTMLForm
 735          */
 736         protected function alterForm( HTMLForm $form ) {}
 737
 738         /**
 739          * Get the HTMLForm to control behaviour
 740          * @return HTMLForm|null
 741          */
 742         protected function getForm() {
 743                 $this->fields = $this->getFormFields();
 744
 745                 $form = new HTMLForm( $this->fields, $this->getContext() );
 746                 $form->setSubmitCallback( array( $this, 'onSubmit' ) );
 747                 $form->setWrapperLegend( $this->msg( strtolower( $this->getName() ) . '-legend' ) );
 748                 $form->addHeaderText(
 749                         $this->msg( strtolower( $this->getName() ) . '-text' )->parseAsBlock() );
 750
 751                 // Retain query parameters (uselang etc)
 752                 $params = array_diff_key(
 753                         $this->getRequest()->getQueryValues(), array( 'title' => null ) );
 754                 $form->addHiddenField( 'redirectparams', wfArrayToCGI( $params ) );
 755
 756                 $form->addPreText( $this->preText() );
 757                 $form->addPostText( $this->postText() );
 758                 $this->alterForm( $form );
 759
 760                 // Give hooks a chance to alter the form, adding extra fields or text etc
 761                 wfRunHooks( "Special{$this->getName()}BeforeFormDisplay", array( &$form ) );
 762
 763                 return $form;
 764         }
 765
 766         /**
 767          * Process the form on POST submission.
 768          * @param  $data Array
 769          * @return Bool|Array true for success, false for didn't-try, array of errors on failure
 770          */
 771         public abstract function onSubmit( array $data );
 772
 773         /**
 774          * Do something exciting on successful processing of the form, most likely to show a
 775          * confirmation message
 776          */
 777         public abstract function onSuccess();
 778
 779         /**
 780          * Basic SpecialPage workflow: get a form, send it to the user; get some data back,
 781          *
 782          * @param $par String Subpage string if one was specified
 783          */
 784         public function execute( $par ) {
 785                 $this->setParameter( $par );
 786                 $this->setHeaders();
 787
 788                 // This will throw exceptions if there's a problem
 789                 $this->userCanExecute( $this->getUser() );
 790
 791                 $form = $this->getForm();
 792                 if ( $form->show() ) {
 793                         $this->onSuccess();
 794                 }
 795         }
 796
 797         /**
 798          * Maybe do something interesting with the subpage parameter
 799          * @param $par String
 800          */
 801         protected function setParameter( $par ){}
 802
 803         /**
 804          * Checks if the given user (identified by an object) can perform this action.  Can be
 805          * overridden by sub-classes with more complicated permissions schemes.  Failures here
 806          * must throw subclasses of ErrorPageError
 807          *
 808          * @param $user User: the user to check, or null to use the context user
 809          * @return Bool true
 810          * @throws ErrorPageError
 811          */
 812         public function userCanExecute( User $user ) {
 813                 if ( $this->requiresWrite() && wfReadOnly() ) {
 814                         throw new ReadOnlyError();
 815                 }
 816
 817                 if ( $this->getRestriction() !== null && !$user->isAllowed( $this->getRestriction() ) ) {
 818                         throw new PermissionsError( $this->getRestriction() );
 819                 }
 820
 821                 if ( $this->requiresUnblock() && $user->isBlocked() ) {
 822                         $block = $user->mBlock;
 823                         throw new UserBlockedError( $block );
 824                 }
 825
 826                 return true;
 827         }
 828
 829         /**
 830          * Whether this action requires the wiki not to be locked
 831          * @return Bool
 832          */
 833         public function requiresWrite() {
 834                 return true;
 835         }
 836
 837         /**
 838          * Whether this action cannot be executed by a blocked user
 839          * @return Bool
 840          */
 841         public function requiresUnblock() {
 842                 return true;
 843         }
 844 }
 845
 846 /**
 847  * Shortcut to construct a special page which is unlisted by default
 848  * @ingroup SpecialPage
 849  */
 850 class UnlistedSpecialPage extends SpecialPage {
 851         function __construct( $name, $restriction = '', $function = false, $file = 'default' ) {
 852                 parent::__construct( $name, $restriction, false, $function, $file );
 853         }
 854
 855         public function isListed(){
 856                 return false;
 857         }
 858 }
 859
 860 /**
 861  * Shortcut to construct an includable special  page
 862  * @ingroup SpecialPage
 863  */
 864 class IncludableSpecialPage extends SpecialPage {
 865         function __construct(
 866                 $name, $restriction = '', $listed = true, $function = false, $file = 'default'
 867         ) {
 868                 parent::__construct( $name, $restriction, $listed, $function, $file, true );
 869         }
 870
 871         public function isIncludable(){
 872                 return true;
 873         }
 874 }
 875
 876 /**
 877  * Shortcut to construct a special page alias.
 878  * @ingroup SpecialPage
 879  */
 880 abstract class RedirectSpecialPage extends UnlistedSpecialPage {
 881
 882         // Query parameters that can be passed through redirects
 883         protected $mAllowedRedirectParams = array();
 884
 885         // Query parameteres added by redirects
 886         protected $mAddedRedirectParams = array();
 887
 888         public function execute( $par ){
 889                 $redirect = $this->getRedirect( $par );
 890                 $query = $this->getRedirectQuery();
 891                 // Redirect to a page title with possible query parameters
 892                 if ( $redirect instanceof Title ) {
 893                         $url = $redirect->getFullUrl( $query );
 894                         $this->getOutput()->redirect( $url );
 895                         wfProfileOut( __METHOD__ );
 896                         return $redirect;
 897                 // Redirect to index.php with query parameters
 898                 } elseif ( $redirect === true ) {
 899                         global $wgScript;
 900                         $url = $wgScript . '?' . wfArrayToCGI( $query );
 901                         $this->getOutput()->redirect( $url );
 902                         wfProfileOut( __METHOD__ );
 903                         return $redirect;
 904                 } else {
 905                         $class = __CLASS__;
 906                         throw new MWException( "RedirectSpecialPage $class doesn't redirect!" );
 907                 }
 908         }
 909
 910         /**
 911          * If the special page is a redirect, then get the Title object it redirects to.
 912          * False otherwise.
 913          *
 914          * @param $par String Subpage string
 915          * @return Title|false
 916          */
 917         abstract public function getRedirect( $par );
 918
 919         /**
 920          * Return part of the request string for a special redirect page
 921          * This allows passing, e.g. action=history to Special:Mypage, etc.
 922          *
 923          * @return String
 924          */
 925         public function getRedirectQuery() {
 926                 $params = array();
 927
 928                 foreach( $this->mAllowedRedirectParams as $arg ) {
 929                         if( $this->getRequest()->getVal( $arg, null ) !== null ){
 930                                 $params[$arg] = $this->getRequest()->getVal( $arg );
 931                         }
 932                 }
 933
 934                 foreach( $this->mAddedRedirectParams as $arg => $val ) {
 935                         $params[$arg] = $val;
 936                 }
 937
 938                 return count( $params )
 939                         ? $params
 940                         : false;
 941         }
 942 }
 943
 944 abstract class SpecialRedirectToSpecial extends RedirectSpecialPage {
 945         var $redirName, $redirSubpage;
 946
 947         function __construct(
 948                 $name, $redirName, $redirSubpage = false,
 949                 $allowedRedirectParams = array(), $addedRedirectParams = array()
 950         ) {
 951                 parent::__construct( $name );
 952                 $this->redirName = $redirName;
 953                 $this->redirSubpage = $redirSubpage;
 954                 $this->mAllowedRedirectParams = $allowedRedirectParams;
 955                 $this->mAddedRedirectParams = $addedRedirectParams;
 956         }
 957
 958         public function getRedirect( $subpage ) {
 959                 if ( $this->redirSubpage === false ) {
 960                         return SpecialPage::getTitleFor( $this->redirName, $subpage );
 961                 } else {
 962                         return SpecialPage::getTitleFor( $this->redirName, $this->redirSubpage );
 963                 }
 964         }
 965 }
 966
 967 /**
 968  * ListAdmins --> ListUsers/admin
 969  */
 970 class SpecialListAdmins extends SpecialRedirectToSpecial {
 971         function __construct(){
 972                 parent::__construct( 'ListAdmins', 'ListUsers', 'sysop' );
 973         }
 974 }
 975
 976 /**
 977  * ListBots --> ListUsers/admin
 978  */
 979 class SpecialListBots extends SpecialRedirectToSpecial {
 980         function __construct(){
 981                 parent::__construct( 'ListAdmins', 'ListUsers', 'bot' );
 982         }
 983 }
 984
 985 /**
 986  * CreateAccount --> UserLogin/signup
 987  * @todo FIXME: This (and the rest of the login frontend) needs to die a horrible painful death
 988  */
 989 class SpecialCreateAccount extends SpecialRedirectToSpecial {
 990         function __construct(){
 991                 parent::__construct( 'CreateAccount', 'Userlogin', 'signup', array( 'uselang' ) );
 992         }
 993 }
 994 /**
 995  * SpecialMypage, SpecialMytalk and SpecialMycontributions special pages
 996  * are used to get user independant links pointing to the user page, talk
 997  * page and list of contributions.
 998  * This can let us cache a single copy of any generated content for all
 999  * users.
1000  */
1001
1002 /**
1003  * Shortcut to construct a special page pointing to current user user's page.
1004  * @ingroup SpecialPage
1005  */
1006 class SpecialMypage extends RedirectSpecialPage {
1007         function __construct() {
1008                 parent::__construct( 'Mypage' );
1009                 $this->mAllowedRedirectParams = array( 'action' , 'preload' , 'editintro',
1010                         'section', 'oldid', 'diff', 'dir',
1011                         // Options for action=raw; missing ctype can break JS or CSS in some browsers
1012                         'ctype', 'maxage', 'smaxage' );
1013         }
1014
1015         function getRedirect( $subpage ) {
1016                 if ( strval( $subpage ) !== '' ) {
1017                         return Title::makeTitle( NS_USER, $this->getUser()->getName() . '/' . $subpage );
1018                 } else {
1019                         return Title::makeTitle( NS_USER, $this->getUser()->getName() );
1020                 }
1021         }
1022 }
1023
1024 /**
1025  * Shortcut to construct a special page pointing to current user talk page.
1026  * @ingroup SpecialPage
1027  */
1028 class SpecialMytalk extends RedirectSpecialPage {
1029         function __construct() {
1030                 parent::__construct( 'Mytalk' );
1031                 $this->mAllowedRedirectParams = array( 'action' , 'preload' , 'editintro',
1032                         'section', 'oldid', 'diff', 'dir' );
1033         }
1034
1035         function getRedirect( $subpage ) {
1036                 if ( strval( $subpage ) !== '' ) {
1037                         return Title::makeTitle( NS_USER_TALK, $this->getUser()->getName() . '/' . $subpage );
1038                 } else {
1039                         return Title::makeTitle( NS_USER_TALK, $this->getUser()->getName() );
1040                 }
1041         }
1042 }
1043
1044 /**
1045  * Shortcut to construct a special page pointing to current user contributions.
1046  * @ingroup SpecialPage
1047  */
1048 class SpecialMycontributions extends RedirectSpecialPage {
1049         function __construct() {
1050                 parent::__construct(  'Mycontributions' );
1051                 $this->mAllowedRedirectParams = array( 'limit', 'namespace', 'tagfilter',
1052                         'offset', 'dir', 'year', 'month', 'feed' );
1053         }
1054
1055         function getRedirect( $subpage ) {
1056                 return SpecialPage::getTitleFor( 'Contributions', $this->getUser()->getName() );
1057         }
1058 }
1059
1060 /**
1061  * Redirect to Special:Listfiles?user=$wgUser
1062  */
1063 class SpecialMyuploads extends RedirectSpecialPage {
1064         function __construct() {
1065                 parent::__construct( 'Myuploads' );
1066                 $this->mAllowedRedirectParams = array( 'limit' );
1067         }
1068
1069         function getRedirect( $subpage ) {
1070                 return SpecialPage::getTitleFor( 'Listfiles', $this->getUser()->getName() );
1071         }
1072 }
1073
1074 /**
1075  * Redirect from Special:PermanentLink/### to index.php?oldid=###
1076  */
1077 class SpecialPermanentLink extends RedirectSpecialPage {
1078         function __construct() {
1079                 parent::__construct( 'PermanentLink' );
1080                 $this->mAllowedRedirectParams = array();
1081         }
1082
1083         function getRedirect( $subpage ) {
1084                 $subpage = intval( $subpage );
1085                 $this->mAddedRedirectParams['oldid'] = $subpage;
1086                 return true;
1087         }
1088 }