includes/SpecialPage.php

   1 <?php
   2 /**
   3  * Parent class for all special pages.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup SpecialPage
  22  */
  23
  24 /**
  25  * Parent special page class, also static functions for handling the special
  26  * page list.
  27  * @ingroup SpecialPage
  28  */
  29 class SpecialPage {
  30
  31         // The canonical name of this special page
  32         // Also used for the default <h1> heading, @see getDescription()
  33         protected $mName;
  34
  35         // The local name of this special page
  36         private $mLocalName;
  37
  38         // Minimum user level required to access this page, or "" for anyone.
  39         // Also used to categorise the pages in Special:Specialpages
  40         private $mRestriction;
  41
  42         // Listed in Special:Specialpages?
  43         private $mListed;
  44
  45         // Function name called by the default execute()
  46         private $mFunction;
  47
  48         // File which needs to be included before the function above can be called
  49         private $mFile;
  50
  51         // Whether or not this special page is being included from an article
  52         protected $mIncluding;
  53
  54         // Whether the special page can be included in an article
  55         protected $mIncludable;
  56
  57         /**
  58          * Current request context
  59          * @var IContextSource
  60          */
  61         protected $mContext;
  62
  63         /**
  64          * Initialise the special page list
  65          * This must be called before accessing SpecialPage::$mList
  66          * @deprecated since 1.18
  67          */
  68         static function initList() {
  69                 wfDeprecated( __METHOD__, '1.18' );
  70                 // Noop
  71         }
  72
  73         /**
  74          * @deprecated since 1.18
  75          */
  76         static function initAliasList() {
  77                 wfDeprecated( __METHOD__, '1.18' );
  78                 // Noop
  79         }
  80
  81         /**
  82          * Given a special page alias, return the special page name.
  83          * Returns false if there is no such alias.
  84          *
  85          * @param $alias String
  86          * @return String or false
  87          * @deprecated since 1.18 call SpecialPageFactory method directly
  88          */
  89         static function resolveAlias( $alias ) {
  90                 wfDeprecated( __METHOD__, '1.18' );
  91                 list( $name, /*...*/ ) = SpecialPageFactory::resolveAlias( $alias );
  92                 return $name;
  93         }
  94
  95         /**
  96          * Given a special page name with a possible subpage, return an array
  97          * where the first element is the special page name and the second is the
  98          * subpage.
  99          *
 100          * @param $alias String
 101          * @return Array
 102          * @deprecated since 1.18 call SpecialPageFactory method directly
 103          */
 104         static function resolveAliasWithSubpage( $alias ) {
 105                 return SpecialPageFactory::resolveAlias( $alias );
 106         }
 107
 108         /**
 109          * Add a page to the list of valid special pages. This used to be the preferred
 110          * method for adding special pages in extensions. It's now suggested that you add
 111          * an associative record to $wgSpecialPages. This avoids autoloading SpecialPage.
 112          *
 113          * @param $page SpecialPage
 114          * @deprecated since 1.7, warnings in 1.17, might be removed in 1.20
 115          */
 116         static function addPage( &$page ) {
 117                 wfDeprecated( __METHOD__, '1.7' );
 118                 SpecialPageFactory::getList()->{$page->mName} = $page;
 119         }
 120
 121         /**
 122          * Add a page to a certain display group for Special:SpecialPages
 123          *
 124          * @param $page Mixed: SpecialPage or string
 125          * @param $group String
 126          * @deprecated since 1.18 call SpecialPageFactory method directly
 127          */
 128         static function setGroup( $page, $group ) {
 129                 wfDeprecated( __METHOD__, '1.18' );
 130                 SpecialPageFactory::setGroup( $page, $group );
 131         }
 132
 133         /**
 134          * Get the group that the special page belongs in on Special:SpecialPage
 135          *
 136          * @param $page SpecialPage
 137          * @return string
 138          * @deprecated since 1.18 call SpecialPageFactory method directly
 139          */
 140         static function getGroup( &$page ) {
 141                 wfDeprecated( __METHOD__, '1.18' );
 142                 return SpecialPageFactory::getGroup( $page );
 143         }
 144
 145         /**
 146          * Remove a special page from the list
 147          * Formerly used to disable expensive or dangerous special pages. The
 148          * preferred method is now to add a SpecialPage_initList hook.
 149          * @deprecated since 1.18
 150          *
 151          * @param $name String the page to remove
 152          */
 153         static function removePage( $name ) {
 154                 wfDeprecated( __METHOD__, '1.18' );
 155                 unset( SpecialPageFactory::getList()->$name );
 156         }
 157
 158         /**
 159          * Check if a given name exist as a special page or as a special page alias
 160          *
 161          * @param $name String: name of a special page
 162          * @return Boolean: true if a special page exists with this name
 163          * @deprecated since 1.18 call SpecialPageFactory method directly
 164          */
 165         static function exists( $name ) {
 166                 wfDeprecated( __METHOD__, '1.18' );
 167                 return SpecialPageFactory::exists( $name );
 168         }
 169
 170         /**
 171          * Find the object with a given name and return it (or NULL)
 172          *
 173          * @param $name String
 174          * @return SpecialPage object or null if the page doesn't exist
 175          * @deprecated since 1.18 call SpecialPageFactory method directly
 176          */
 177         static function getPage( $name ) {
 178                 wfDeprecated( __METHOD__, '1.18' );
 179                 return SpecialPageFactory::getPage( $name );
 180         }
 181
 182         /**
 183          * Get a special page with a given localised name, or NULL if there
 184          * is no such special page.
 185          *
 186          * @param $alias String
 187          * @return SpecialPage object or null if the page doesn't exist
 188          * @deprecated since 1.18 call SpecialPageFactory method directly
 189          */
 190         static function getPageByAlias( $alias ) {
 191                 wfDeprecated( __METHOD__, '1.18' );
 192                 return SpecialPageFactory::getPage( $alias );
 193         }
 194
 195         /**
 196          * Return categorised listable special pages which are available
 197          * for the current user, and everyone.
 198          *
 199          * @param $user User object to check permissions, $wgUser will be used
 200          *              if not provided
 201          * @return array Associative array mapping page's name to its SpecialPage object
 202          * @deprecated since 1.18 call SpecialPageFactory method directly
 203          */
 204         static function getUsablePages( User $user = null ) {
 205                 wfDeprecated( __METHOD__, '1.18' );
 206                 return SpecialPageFactory::getUsablePages( $user );
 207         }
 208
 209         /**
 210          * Return categorised listable special pages for all users
 211          *
 212          * @return array Associative array mapping page's name to its SpecialPage object
 213          * @deprecated since 1.18 call SpecialPageFactory method directly
 214          */
 215         static function getRegularPages() {
 216                 wfDeprecated( __METHOD__, '1.18' );
 217                 return SpecialPageFactory::getRegularPages();
 218         }
 219
 220         /**
 221          * Return categorised listable special pages which are available
 222          * for the current user, but not for everyone
 223          *
 224          * @return array Associative array mapping page's name to its SpecialPage object
 225          * @deprecated since 1.18 call SpecialPageFactory method directly
 226          */
 227         static function getRestrictedPages() {
 228                 wfDeprecated( __METHOD__, '1.18' );
 229                 return SpecialPageFactory::getRestrictedPages();
 230         }
 231
 232         /**
 233          * Execute a special page path.
 234          * The path may contain parameters, e.g. Special:Name/Params
 235          * Extracts the special page name and call the execute method, passing the parameters
 236          *
 237          * Returns a title object if the page is redirected, false if there was no such special
 238          * page, and true if it was successful.
 239          *
 240          * @param $title          Title object
 241          * @param $context        IContextSource
 242          * @param $including      Bool output is being captured for use in {{special:whatever}}
 243          * @return Bool
 244          * @deprecated since 1.18 call SpecialPageFactory method directly
 245          */
 246         public static function executePath( &$title, IContextSource &$context, $including = false ) {
 247                 wfDeprecated( __METHOD__, '1.18' );
 248                 return SpecialPageFactory::executePath( $title, $context, $including );
 249         }
 250
 251         /**
 252          * Get the local name for a specified canonical name
 253          *
 254          * @param $name String
 255          * @param $subpage Mixed: boolean false, or string
 256          *
 257          * @return String
 258          * @deprecated since 1.18 call SpecialPageFactory method directly
 259          */
 260         static function getLocalNameFor( $name, $subpage = false ) {
 261                 wfDeprecated( __METHOD__, '1.18' );
 262                 return SpecialPageFactory::getLocalNameFor( $name, $subpage );
 263         }
 264
 265         /**
 266          * Get a localised Title object for a specified special page name
 267          *
 268          * @param $name String
 269          * @param $subpage String|Bool subpage string, or false to not use a subpage
 270          * @return Title object
 271          */
 272         public static function getTitleFor( $name, $subpage = false ) {
 273                 $name = SpecialPageFactory::getLocalNameFor( $name, $subpage );
 274                 if ( $name ) {
 275                         return Title::makeTitle( NS_SPECIAL, $name );
 276                 } else {
 277                         throw new MWException( "Invalid special page name \"$name\"" );
 278                 }
 279         }
 280
 281         /**
 282          * Get a localised Title object for a page name with a possibly unvalidated subpage
 283          *
 284          * @param $name String
 285          * @param $subpage String|Bool subpage string, or false to not use a subpage
 286          * @return Title object or null if the page doesn't exist
 287          */
 288         public static function getSafeTitleFor( $name, $subpage = false ) {
 289                 $name = SpecialPageFactory::getLocalNameFor( $name, $subpage );
 290                 if ( $name ) {
 291                         return Title::makeTitleSafe( NS_SPECIAL, $name );
 292                 } else {
 293                         return null;
 294                 }
 295         }
 296
 297         /**
 298          * Get a title for a given alias
 299          *
 300          * @param $alias String
 301          * @return Title or null if there is no such alias
 302          * @deprecated since 1.18 call SpecialPageFactory method directly
 303          */
 304         static function getTitleForAlias( $alias ) {
 305                 wfDeprecated( __METHOD__, '1.18' );
 306                 return SpecialPageFactory::getTitleForAlias( $alias );
 307         }
 308
 309         /**
 310          * Default constructor for special pages
 311          * Derivative classes should call this from their constructor
 312          *     Note that if the user does not have the required level, an error message will
 313          *     be displayed by the default execute() method, without the global function ever
 314          *     being called.
 315          *
 316          *     If you override execute(), you can recover the default behaviour with userCanExecute()
 317          *     and displayRestrictionError()
 318          *
 319          * @param $name String: name of the special page, as seen in links and URLs
 320          * @param $restriction String: user right required, e.g. "block" or "delete"
 321          * @param $listed Bool: whether the page is listed in Special:Specialpages
 322          * @param $function Callback|Bool: function called by execute(). By default it is constructed from $name
 323          * @param $file String: file which is included by execute(). It is also constructed from $name by default
 324          * @param $includable Bool: whether the page can be included in normal pages
 325          */
 326         public function __construct(
 327                 $name = '', $restriction = '', $listed = true,
 328                 $function = false, $file = 'default', $includable = false
 329         ) {
 330                 $this->init( $name, $restriction, $listed, $function, $file, $includable );
 331         }
 332
 333         /**
 334          * Do the real work for the constructor, mainly so __call() can intercept
 335          * calls to SpecialPage()
 336          * @param $name String: name of the special page, as seen in links and URLs
 337          * @param $restriction String: user right required, e.g. "block" or "delete"
 338          * @param $listed Bool: whether the page is listed in Special:Specialpages
 339          * @param $function Callback|Bool: function called by execute(). By default it is constructed from $name
 340          * @param $file String: file which is included by execute(). It is also constructed from $name by default
 341          * @param $includable Bool: whether the page can be included in normal pages
 342          */
 343         private function init( $name, $restriction, $listed, $function, $file, $includable ) {
 344                 $this->mName = $name;
 345                 $this->mRestriction = $restriction;
 346                 $this->mListed = $listed;
 347                 $this->mIncludable = $includable;
 348                 if ( !$function ) {
 349                         $this->mFunction = 'wfSpecial' . $name;
 350                 } else {
 351                         $this->mFunction = $function;
 352                 }
 353                 if ( $file === 'default' ) {
 354                         $this->mFile = dirname( __FILE__ ) . "/specials/Special$name.php";
 355                 } else {
 356                         $this->mFile = $file;
 357                 }
 358         }
 359
 360         /**
 361          * Use PHP's magic __call handler to get calls to the old PHP4 constructor
 362          * because PHP E_STRICT yells at you for having __construct() and SpecialPage()
 363          *
 364          * @param $fName String Name of called method
 365          * @param $a Array Arguments to the method
 366          * @deprecated since 1.17, call parent::__construct()
 367          */
 368         public function __call( $fName, $a ) {
 369                 // Deprecated messages now, remove in 1.19 or 1.20?
 370                 wfDeprecated( __METHOD__, '1.17' );
 371
 372                 // Sometimes $fName is SpecialPage, sometimes it's specialpage. <3 PHP
 373                 if ( strtolower( $fName ) == 'specialpage' ) {
 374                         $name = isset( $a[0] ) ? $a[0] : '';
 375                         $restriction = isset( $a[1] ) ? $a[1] : '';
 376                         $listed = isset( $a[2] ) ? $a[2] : true;
 377                         $function = isset( $a[3] ) ? $a[3] : false;
 378                         $file = isset( $a[4] ) ? $a[4] : 'default';
 379                         $includable = isset( $a[5] ) ? $a[5] : false;
 380                         $this->init( $name, $restriction, $listed, $function, $file, $includable );
 381                 } else {
 382                         $className = get_class( $this );
 383                         throw new MWException( "Call to undefined method $className::$fName" );
 384                 }
 385         }
 386
 387         /**
 388          * Get the name of this Special Page.
 389          * @return String
 390          */
 391         function getName() {
 392                 return $this->mName;
 393         }
 394
 395         /**
 396          * Get the permission that a user must have to execute this page
 397          * @return String
 398          */
 399         function getRestriction() {
 400                 return $this->mRestriction;
 401         }
 402
 403         /**
 404          * Get the file which will be included by SpecialPage::execute() if your extension is
 405          * still stuck in the past and hasn't overridden the execute() method.  No modern code
 406          * should want or need to know this.
 407          * @return String
 408          * @deprecated since 1.18
 409          */
 410         function getFile() {
 411                 wfDeprecated( __METHOD__, '1.18' );
 412                 return $this->mFile;
 413         }
 414
 415         // @todo FIXME: Decide which syntax to use for this, and stick to it
 416         /**
 417          * Whether this special page is listed in Special:SpecialPages
 418          * @since r3583 (v1.3)
 419          * @return Bool
 420          */
 421         function isListed() {
 422                 return $this->mListed;
 423         }
 424         /**
 425          * Set whether this page is listed in Special:Specialpages, at run-time
 426          * @since r3583 (v1.3)
 427          * @param $listed Bool
 428          * @return Bool
 429          */
 430         function setListed( $listed ) {
 431                 return wfSetVar( $this->mListed, $listed );
 432         }
 433         /**
 434          * Get or set whether this special page is listed in Special:SpecialPages
 435          * @since r11308 (v1.6)
 436          * @param $x Bool
 437          * @return Bool
 438          */
 439         function listed( $x = null ) {
 440                 return wfSetVar( $this->mListed, $x );
 441         }
 442
 443         /**
 444          * Whether it's allowed to transclude the special page via {{Special:Foo/params}}
 445          * @return Bool
 446          */
 447         public function isIncludable() {
 448                 return $this->mIncludable;
 449         }
 450
 451         /**
 452          * These mutators are very evil, as the relevant variables should not mutate.  So
 453          * don't use them.
 454          * @param $x Mixed
 455          * @return Mixed
 456          * @deprecated since 1.18
 457          */
 458         function name( $x = null ) { wfDeprecated( __METHOD__, '1.18' ); return wfSetVar( $this->mName, $x ); }
 459
 460         /**
 461          * These mutators are very evil, as the relevant variables should not mutate.  So
 462          * don't use them.
 463          * @param $x Mixed
 464          * @return Mixed
 465          * @deprecated since 1.18
 466          */
 467         function restriction( $x = null ) { wfDeprecated( __METHOD__, '1.18' ); return wfSetVar( $this->mRestriction, $x ); }
 468
 469         /**
 470          * These mutators are very evil, as the relevant variables should not mutate.  So
 471          * don't use them.
 472          * @param $x Mixed
 473          * @return Mixed
 474          * @deprecated since 1.18
 475          */
 476         function func( $x = null ) { wfDeprecated( __METHOD__, '1.18' ); return wfSetVar( $this->mFunction, $x ); }
 477
 478         /**
 479          * These mutators are very evil, as the relevant variables should not mutate.  So
 480          * don't use them.
 481          * @param $x Mixed
 482          * @return Mixed
 483          * @deprecated since 1.18
 484          */
 485         function file( $x = null ) { wfDeprecated( __METHOD__, '1.18' ); return wfSetVar( $this->mFile, $x ); }
 486
 487         /**
 488          * These mutators are very evil, as the relevant variables should not mutate.  So
 489          * don't use them.
 490          * @param $x Mixed
 491          * @return Mixed
 492          * @deprecated since 1.18
 493          */
 494         function includable( $x = null ) { wfDeprecated( __METHOD__, '1.18' ); return wfSetVar( $this->mIncludable, $x ); }
 495
 496         /**
 497          * Whether the special page is being evaluated via transclusion
 498          * @param $x Bool
 499          * @return Bool
 500          */
 501         function including( $x = null ) {
 502                 return wfSetVar( $this->mIncluding, $x );
 503         }
 504
 505         /**
 506          * Get the localised name of the special page
 507          */
 508         function getLocalName() {
 509                 if ( !isset( $this->mLocalName ) ) {
 510                         $this->mLocalName = SpecialPageFactory::getLocalNameFor( $this->mName );
 511                 }
 512                 return $this->mLocalName;
 513         }
 514
 515         /**
 516          * Is this page expensive (for some definition of expensive)?
 517          * Expensive pages are disabled or cached in miser mode.  Originally used
 518          * (and still overridden) by QueryPage and subclasses, moved here so that
 519          * Special:SpecialPages can safely call it for all special pages.
 520          *
 521          * @return Boolean
 522          */
 523         public function isExpensive() {
 524                 return false;
 525         }
 526
 527         /**
 528          * Can be overridden by subclasses with more complicated permissions
 529          * schemes.
 530          *
 531          * @return Boolean: should the page be displayed with the restricted-access
 532          *   pages?
 533          */
 534         public function isRestricted() {
 535                 global $wgGroupPermissions;
 536                 // DWIM: If all anons can do something, then it is not restricted
 537                 return $this->mRestriction != '' && empty( $wgGroupPermissions['*'][$this->mRestriction] );
 538         }
 539
 540         /**
 541          * Checks if the given user (identified by an object) can execute this
 542          * special page (as defined by $mRestriction).  Can be overridden by sub-
 543          * classes with more complicated permissions schemes.
 544          *
 545          * @param $user User: the user to check
 546          * @return Boolean: does the user have permission to view the page?
 547          */
 548         public function userCanExecute( User $user ) {
 549                 return $user->isAllowed( $this->mRestriction );
 550         }
 551
 552         /**
 553          * Output an error message telling the user what access level they have to have
 554          */
 555         function displayRestrictionError() {
 556                 throw new PermissionsError( $this->mRestriction );
 557         }
 558
 559         /**
 560          * Checks if userCanExecute, and if not throws a PermissionsError
 561          *
 562          * @since 1.19
 563          */
 564         public function checkPermissions() {
 565                 if ( !$this->userCanExecute( $this->getUser() ) ) {
 566                         $this->displayRestrictionError();
 567                 }
 568         }
 569
 570         /**
 571          * If the wiki is currently in readonly mode, throws a ReadOnlyError
 572          *
 573          * @since 1.19
 574          * @throws ReadOnlyError
 575          */
 576         public function checkReadOnly() {
 577                 if ( wfReadOnly() ) {
 578                         throw new ReadOnlyError;
 579                 }
 580         }
 581
 582         /**
 583          * Sets headers - this should be called from the execute() method of all derived classes!
 584          */
 585         function setHeaders() {
 586                 $out = $this->getOutput();
 587                 $out->setArticleRelated( false );
 588                 $out->setRobotPolicy( "noindex,nofollow" );
 589                 $out->setPageTitle( $this->getDescription() );
 590         }
 591
 592         /**
 593          * Default execute method
 594          * Checks user permissions, calls the function given in mFunction
 595          *
 596          * This must be overridden by subclasses; it will be made abstract in a future version
 597          *
 598          * @param $par String subpage string, if one was specified
 599          */
 600         function execute( $par ) {
 601                 $this->setHeaders();
 602                 $this->checkPermissions();
 603
 604                 $func = $this->mFunction;
 605                 // only load file if the function does not exist
 606                 if ( !is_callable( $func ) && $this->mFile ) {
 607                         require_once( $this->mFile );
 608                 }
 609                 $this->outputHeader();
 610                 call_user_func( $func, $par, $this );
 611         }
 612
 613         /**
 614          * Outputs a summary message on top of special pages
 615          * Per default the message key is the canonical name of the special page
 616          * May be overriden, i.e. by extensions to stick with the naming conventions
 617          * for message keys: 'extensionname-xxx'
 618          *
 619          * @param $summaryMessageKey String: message key of the summary
 620          */
 621         function outputHeader( $summaryMessageKey = '' ) {
 622                 global $wgContLang;
 623
 624                 if ( $summaryMessageKey == '' ) {
 625                         $msg = $wgContLang->lc( $this->getName() ) . '-summary';
 626                 } else {
 627                         $msg = $summaryMessageKey;
 628                 }
 629                 if ( !$this->msg( $msg )->isDisabled() && !$this->including() ) {
 630                         $this->getOutput()->wrapWikiMsg(
 631                                 "<div class='mw-specialpage-summary'>\n$1\n</div>", $msg );
 632                 }
 633
 634         }
 635
 636         /**
 637          * Returns the name that goes in the \<h1\> in the special page itself, and
 638          * also the name that will be listed in Special:Specialpages
 639          *
 640          * Derived classes can override this, but usually it is easier to keep the
 641          * default behaviour. Messages can be added at run-time, see
 642          * MessageCache.php.
 643          *
 644          * @return String
 645          */
 646         function getDescription() {
 647                 return $this->msg( strtolower( $this->mName ) )->text();
 648         }
 649
 650         /**
 651          * Get a self-referential title object
 652          *
 653          * @param $subpage String|Bool
 654          * @return Title object
 655          */
 656         function getTitle( $subpage = false ) {
 657                 return self::getTitleFor( $this->mName, $subpage );
 658         }
 659
 660         /**
 661          * Sets the context this SpecialPage is executed in
 662          *
 663          * @param $context IContextSource
 664          * @since 1.18
 665          */
 666         public function setContext( $context ) {
 667                 $this->mContext = $context;
 668         }
 669
 670         /**
 671          * Gets the context this SpecialPage is executed in
 672          *
 673          * @return IContextSource|RequestContext
 674          * @since 1.18
 675          */
 676         public function getContext() {
 677                 if ( $this->mContext instanceof IContextSource ) {
 678                         return $this->mContext;
 679                 } else {
 680                         wfDebug( __METHOD__ . " called and \$mContext is null. Return RequestContext::getMain(); for sanity\n" );
 681                         return RequestContext::getMain();
 682                 }
 683         }
 684
 685         /**
 686          * Get the WebRequest being used for this instance
 687          *
 688          * @return WebRequest
 689          * @since 1.18
 690          */
 691         public function getRequest() {
 692                 return $this->getContext()->getRequest();
 693         }
 694
 695         /**
 696          * Get the OutputPage being used for this instance
 697          *
 698          * @return OutputPage
 699          * @since 1.18
 700          */
 701         public function getOutput() {
 702                 return $this->getContext()->getOutput();
 703         }
 704
 705         /**
 706          * Shortcut to get the User executing this instance
 707          *
 708          * @return User
 709          * @since 1.18
 710          */
 711         public function getUser() {
 712                 return $this->getContext()->getUser();
 713         }
 714
 715         /**
 716          * Shortcut to get the skin being used for this instance
 717          *
 718          * @return Skin
 719          * @since 1.18
 720          */
 721         public function getSkin() {
 722                 return $this->getContext()->getSkin();
 723         }
 724
 725         /**
 726          * Shortcut to get user's language
 727          *
 728          * @deprecated 1.19 Use getLanguage instead
 729          * @return Language
 730          * @since 1.18
 731          */
 732         public function getLang() {
 733                 wfDeprecated( __METHOD__, '1.19' );
 734                 return $this->getLanguage();
 735         }
 736
 737         /**
 738          * Shortcut to get user's language
 739          *
 740          * @return Language
 741          * @since 1.19
 742          */
 743         public function getLanguage() {
 744                 return $this->getContext()->getLanguage();
 745         }
 746
 747         /**
 748          * Return the full title, including $par
 749          *
 750          * @return Title
 751          * @since 1.18
 752          */
 753         public function getFullTitle() {
 754                 return $this->getContext()->getTitle();
 755         }
 756
 757         /**
 758          * Wrapper around wfMessage that sets the current context.
 759          *
 760          * @return Message
 761          * @see wfMessage
 762          */
 763         public function msg( /* $args */ ) {
 764                 // Note: can't use func_get_args() directly as second or later item in
 765                 // a parameter list until PHP 5.3 or you get a fatal error.
 766                 // Works fine as the first parameter, which appears elsewhere in the
 767                 // code base. Sighhhh.
 768                 $args = func_get_args();
 769                 $message = call_user_func_array( array( $this->getContext(), 'msg' ), $args );
 770                 // RequestContext passes context to wfMessage, and the language is set from
 771                 // the context, but setting the language for Message class removes the
 772                 // interface message status, which breaks for example usernameless gender
 773                 // invokations. Restore the flag when not including special page in content.
 774                 if ( $this->including() ) {
 775                         $message->setInterfaceMessageFlag( false );
 776                 }
 777                 return $message;
 778         }
 779
 780         /**
 781          * Adds RSS/atom links
 782          *
 783          * @param $params array
 784          */
 785         protected function addFeedLinks( $params ) {
 786                 global $wgFeedClasses;
 787
 788                 $feedTemplate = wfScript( 'api' ) . '?';
 789
 790                 foreach ( $wgFeedClasses as $format => $class ) {
 791                         $theseParams = $params + array( 'feedformat' => $format );
 792                         $url = $feedTemplate . wfArrayToCGI( $theseParams );
 793                         $this->getOutput()->addFeedLink( $format, $url );
 794                 }
 795         }
 796 }
 797
 798 /**
 799  * Special page which uses an HTMLForm to handle processing.  This is mostly a
 800  * clone of FormAction.  More special pages should be built this way; maybe this could be
 801  * a new structure for SpecialPages
 802  */
 803 abstract class FormSpecialPage extends SpecialPage {
 804
 805         /**
 806          * Get an HTMLForm descriptor array
 807          * @return Array
 808          */
 809         protected abstract function getFormFields();
 810
 811         /**
 812          * Add pre- or post-text to the form
 813          * @return String HTML which will be sent to $form->addPreText()
 814          */
 815         protected function preText() { return ''; }
 816         protected function postText() { return ''; }
 817
 818         /**
 819          * Play with the HTMLForm if you need to more substantially
 820          * @param $form HTMLForm
 821          */
 822         protected function alterForm( HTMLForm $form ) {}
 823
 824         /**
 825          * Get the HTMLForm to control behaviour
 826          * @return HTMLForm|null
 827          */
 828         protected function getForm() {
 829                 $this->fields = $this->getFormFields();
 830
 831                 $form = new HTMLForm( $this->fields, $this->getContext() );
 832                 $form->setSubmitCallback( array( $this, 'onSubmit' ) );
 833                 $form->setWrapperLegend( $this->msg( strtolower( $this->getName() ) . '-legend' ) );
 834                 $form->addHeaderText(
 835                         $this->msg( strtolower( $this->getName() ) . '-text' )->parseAsBlock() );
 836
 837                 // Retain query parameters (uselang etc)
 838                 $params = array_diff_key(
 839                         $this->getRequest()->getQueryValues(), array( 'title' => null ) );
 840                 $form->addHiddenField( 'redirectparams', wfArrayToCGI( $params ) );
 841
 842                 $form->addPreText( $this->preText() );
 843                 $form->addPostText( $this->postText() );
 844                 $this->alterForm( $form );
 845
 846                 // Give hooks a chance to alter the form, adding extra fields or text etc
 847                 wfRunHooks( "Special{$this->getName()}BeforeFormDisplay", array( &$form ) );
 848
 849                 return $form;
 850         }
 851
 852         /**
 853          * Process the form on POST submission.
 854          * @param  $data Array
 855          * @return Bool|Array true for success, false for didn't-try, array of errors on failure
 856          */
 857         public abstract function onSubmit( array $data );
 858
 859         /**
 860          * Do something exciting on successful processing of the form, most likely to show a
 861          * confirmation message
 862          */
 863         public abstract function onSuccess();
 864
 865         /**
 866          * Basic SpecialPage workflow: get a form, send it to the user; get some data back,
 867          *
 868          * @param $par String Subpage string if one was specified
 869          */
 870         public function execute( $par ) {
 871                 $this->setParameter( $par );
 872                 $this->setHeaders();
 873
 874                 // This will throw exceptions if there's a problem
 875                 $this->checkExecutePermissions( $this->getUser() );
 876
 877                 $form = $this->getForm();
 878                 if ( $form->show() ) {
 879                         $this->onSuccess();
 880                 }
 881         }
 882
 883         /**
 884          * Maybe do something interesting with the subpage parameter
 885          * @param $par String
 886          */
 887         protected function setParameter( $par ) {}
 888
 889         /**
 890          * Called from execute() to check if the given user can perform this action.
 891          * Failures here must throw subclasses of ErrorPageError.
 892          * @param $user User
 893          * @return Bool true
 894          * @throws ErrorPageError
 895          */
 896         protected function checkExecutePermissions( User $user ) {
 897                 $this->checkPermissions();
 898
 899                 if ( $this->requiresUnblock() && $user->isBlocked() ) {
 900                         $block = $user->getBlock();
 901                         throw new UserBlockedError( $block );
 902                 }
 903
 904                 if ( $this->requiresWrite() ) {
 905                         $this->checkReadOnly();
 906                 }
 907
 908                 return true;
 909         }
 910
 911         /**
 912          * Whether this action requires the wiki not to be locked
 913          * @return Bool
 914          */
 915         public function requiresWrite() {
 916                 return true;
 917         }
 918
 919         /**
 920          * Whether this action cannot be executed by a blocked user
 921          * @return Bool
 922          */
 923         public function requiresUnblock() {
 924                 return true;
 925         }
 926 }
 927
 928 /**
 929  * Shortcut to construct a special page which is unlisted by default
 930  * @ingroup SpecialPage
 931  */
 932 class UnlistedSpecialPage extends SpecialPage {
 933         function __construct( $name, $restriction = '', $function = false, $file = 'default' ) {
 934                 parent::__construct( $name, $restriction, false, $function, $file );
 935         }
 936
 937         public function isListed() {
 938                 return false;
 939         }
 940 }
 941
 942 /**
 943  * Shortcut to construct an includable special  page
 944  * @ingroup SpecialPage
 945  */
 946 class IncludableSpecialPage extends SpecialPage {
 947         function __construct(
 948                 $name, $restriction = '', $listed = true, $function = false, $file = 'default'
 949         ) {
 950                 parent::__construct( $name, $restriction, $listed, $function, $file, true );
 951         }
 952
 953         public function isIncludable() {
 954                 return true;
 955         }
 956 }
 957
 958 /**
 959  * Shortcut to construct a special page alias.
 960  * @ingroup SpecialPage
 961  */
 962 abstract class RedirectSpecialPage extends UnlistedSpecialPage {
 963
 964         // Query parameters that can be passed through redirects
 965         protected $mAllowedRedirectParams = array();
 966
 967         // Query parameteres added by redirects
 968         protected $mAddedRedirectParams = array();
 969
 970         public function execute( $par ) {
 971                 $redirect = $this->getRedirect( $par );
 972                 $query = $this->getRedirectQuery();
 973                 // Redirect to a page title with possible query parameters
 974                 if ( $redirect instanceof Title ) {
 975                         $url = $redirect->getFullUrl( $query );
 976                         $this->getOutput()->redirect( $url );
 977                         wfProfileOut( __METHOD__ );
 978                         return $redirect;
 979                 // Redirect to index.php with query parameters
 980                 } elseif ( $redirect === true ) {
 981                         global $wgScript;
 982                         $url = $wgScript . '?' . wfArrayToCGI( $query );
 983                         $this->getOutput()->redirect( $url );
 984                         wfProfileOut( __METHOD__ );
 985                         return $redirect;
 986                 } else {
 987                         $class = __CLASS__;
 988                         throw new MWException( "RedirectSpecialPage $class doesn't redirect!" );
 989                 }
 990         }
 991
 992         /**
 993          * If the special page is a redirect, then get the Title object it redirects to.
 994          * False otherwise.
 995          *
 996          * @param $par String Subpage string
 997          * @return Title|bool
 998          */
 999         abstract public function getRedirect( $par );
1000
1001         /**
1002          * Return part of the request string for a special redirect page
1003          * This allows passing, e.g. action=history to Special:Mypage, etc.
1004          *
1005          * @return String
1006          */
1007         public function getRedirectQuery() {
1008                 $params = array();
1009
1010                 foreach ( $this->mAllowedRedirectParams as $arg ) {
1011                         if ( $this->getRequest()->getVal( $arg, null ) !== null ) {
1012                                 $params[$arg] = $this->getRequest()->getVal( $arg );
1013                         }
1014                 }
1015
1016                 foreach ( $this->mAddedRedirectParams as $arg => $val ) {
1017                         $params[$arg] = $val;
1018                 }
1019
1020                 return count( $params )
1021                         ? $params
1022                         : false;
1023         }
1024 }
1025
1026 abstract class SpecialRedirectToSpecial extends RedirectSpecialPage {
1027         var $redirName, $redirSubpage;
1028
1029         function __construct(
1030                 $name, $redirName, $redirSubpage = false,
1031                 $allowedRedirectParams = array(), $addedRedirectParams = array()
1032         ) {
1033                 parent::__construct( $name );
1034                 $this->redirName = $redirName;
1035                 $this->redirSubpage = $redirSubpage;
1036                 $this->mAllowedRedirectParams = $allowedRedirectParams;
1037                 $this->mAddedRedirectParams = $addedRedirectParams;
1038         }
1039
1040         public function getRedirect( $subpage ) {
1041                 if ( $this->redirSubpage === false ) {
1042                         return SpecialPage::getTitleFor( $this->redirName, $subpage );
1043                 } else {
1044                         return SpecialPage::getTitleFor( $this->redirName, $this->redirSubpage );
1045                 }
1046         }
1047 }
1048
1049 /**
1050  * ListAdmins --> ListUsers/sysop
1051  */
1052 class SpecialListAdmins extends SpecialRedirectToSpecial {
1053         function __construct() {
1054                 parent::__construct( 'Listadmins', 'Listusers', 'sysop' );
1055         }
1056 }
1057
1058 /**
1059  * ListBots --> ListUsers/bot
1060  */
1061 class SpecialListBots extends SpecialRedirectToSpecial {
1062         function __construct() {
1063                 parent::__construct( 'Listbots', 'Listusers', 'bot' );
1064         }
1065 }
1066
1067 /**
1068  * CreateAccount --> UserLogin/signup
1069  * @todo FIXME: This (and the rest of the login frontend) needs to die a horrible painful death
1070  */
1071 class SpecialCreateAccount extends SpecialRedirectToSpecial {
1072         function __construct() {
1073                 parent::__construct( 'CreateAccount', 'Userlogin', 'signup', array( 'uselang' ) );
1074         }
1075 }
1076 /**
1077  * SpecialMypage, SpecialMytalk and SpecialMycontributions special pages
1078  * are used to get user independant links pointing to the user page, talk
1079  * page and list of contributions.
1080  * This can let us cache a single copy of any generated content for all
1081  * users.
1082  */
1083
1084 /**
1085  * Shortcut to construct a special page pointing to current user user's page.
1086  * @ingroup SpecialPage
1087  */
1088 class SpecialMypage extends RedirectSpecialPage {
1089         function __construct() {
1090                 parent::__construct( 'Mypage' );
1091                 $this->mAllowedRedirectParams = array( 'action', 'preload', 'preloadtitle', 'editintro',
1092                         'section', 'oldid', 'diff', 'dir',
1093                         // Options for action=raw; missing ctype can break JS or CSS in some browsers
1094                         'ctype', 'maxage', 'smaxage' );
1095         }
1096
1097         function getRedirect( $subpage ) {
1098                 if ( strval( $subpage ) !== '' ) {
1099                         return Title::makeTitle( NS_USER, $this->getUser()->getName() . '/' . $subpage );
1100                 } else {
1101                         return Title::makeTitle( NS_USER, $this->getUser()->getName() );
1102                 }
1103         }
1104 }
1105
1106 /**
1107  * Shortcut to construct a special page pointing to current user talk page.
1108  * @ingroup SpecialPage
1109  */
1110 class SpecialMytalk extends RedirectSpecialPage {
1111         function __construct() {
1112                 parent::__construct( 'Mytalk' );
1113                 $this->mAllowedRedirectParams = array( 'action', 'preload', 'preloadtitle', 'editintro',
1114                         'section', 'oldid', 'diff', 'dir' );
1115         }
1116
1117         function getRedirect( $subpage ) {
1118                 if ( strval( $subpage ) !== '' ) {
1119                         return Title::makeTitle( NS_USER_TALK, $this->getUser()->getName() . '/' . $subpage );
1120                 } else {
1121                         return Title::makeTitle( NS_USER_TALK, $this->getUser()->getName() );
1122                 }
1123         }
1124 }
1125
1126 /**
1127  * Shortcut to construct a special page pointing to current user contributions.
1128  * @ingroup SpecialPage
1129  */
1130 class SpecialMycontributions extends RedirectSpecialPage {
1131         function __construct() {
1132                 parent::__construct(  'Mycontributions' );
1133                 $this->mAllowedRedirectParams = array( 'limit', 'namespace', 'tagfilter',
1134                         'offset', 'dir', 'year', 'month', 'feed' );
1135         }
1136
1137         function getRedirect( $subpage ) {
1138                 return SpecialPage::getTitleFor( 'Contributions', $this->getUser()->getName() );
1139         }
1140 }
1141
1142 /**
1143  * Redirect to Special:Listfiles?user=$wgUser
1144  */
1145 class SpecialMyuploads extends RedirectSpecialPage {
1146         function __construct() {
1147                 parent::__construct( 'Myuploads' );
1148                 $this->mAllowedRedirectParams = array( 'limit' );
1149         }
1150
1151         function getRedirect( $subpage ) {
1152                 return SpecialPage::getTitleFor( 'Listfiles', $this->getUser()->getName() );
1153         }
1154 }
1155
1156 /**
1157  * Redirect from Special:PermanentLink/### to index.php?oldid=###
1158  */
1159 class SpecialPermanentLink extends RedirectSpecialPage {
1160         function __construct() {
1161                 parent::__construct( 'PermanentLink' );
1162                 $this->mAllowedRedirectParams = array();
1163         }
1164
1165         function getRedirect( $subpage ) {
1166                 $subpage = intval( $subpage );
1167                 if ( $subpage === 0 ) {
1168                         # throw an error page when no subpage was given
1169                         throw new ErrorPageError( 'nopagetitle', 'nopagetext' );
1170                 }
1171                 $this->mAddedRedirectParams['oldid'] = $subpage;
1172                 return true;
1173         }
1174 }