includes/Title.php

   1 <?php
   2 /**
   3  * See title.txt
   4  * @file
   5  */
   6
   7 if ( !class_exists( 'UtfNormal' ) ) {
   8         require_once( dirname(__FILE__) . '/normal/UtfNormal.php' );
   9 }
  10
  11 define ( 'GAID_FOR_UPDATE', 1 );
  12
  13
  14 /**
  15  * Constants for pr_cascade bitfield
  16  */
  17 define( 'CASCADE', 1 );
  18
  19 /**
  20  * Represents a title within MediaWiki.
  21  * Optionally may contain an interwiki designation or namespace.
  22  * @note This class can fetch various kinds of data from the database;
  23  *       however, it does so inefficiently.
  24  */
  25 class Title {
  26         /** @name Static cache variables */
  27         //@{
  28         static private $titleCache=array();
  29         static private $interwikiCache=array();
  30         //@}
  31
  32         /**
  33          * Title::newFromText maintains a cache to avoid expensive re-normalization of
  34          * commonly used titles. On a batch operation this can become a memory leak
  35          * if not bounded. After hitting this many titles reset the cache.
  36          */
  37         const CACHE_MAX = 1000;
  38
  39
  40         /**
  41          * @name Private member variables
  42          * Please use the accessor functions instead.
  43          * @private
  44          */
  45         //@{
  46
  47         var $mTextform = '';              ///< Text form (spaces not underscores) of the main part
  48         var $mUrlform = '';               ///< URL-encoded form of the main part
  49         var $mDbkeyform = '';             ///< Main part with underscores
  50         var $mUserCaseDBKey;              ///< DB key with the initial letter in the case specified by the user
  51         var $mNamespace = NS_MAIN;        ///< Namespace index, i.e. one of the NS_xxxx constants
  52         var $mInterwiki = '';             ///< Interwiki prefix (or null string)
  53         var $mFragment;                   ///< Title fragment (i.e. the bit after the #)
  54         var $mArticleID = -1;             ///< Article ID, fetched from the link cache on demand
  55         var $mLatestID = false;           ///< ID of most recent revision
  56         var $mRestrictions = array();     ///< Array of groups allowed to edit this article
  57         var $mOldRestrictions = false;
  58         var $mCascadeRestriction;         ///< Cascade restrictions on this page to included templates and images?
  59         var $mRestrictionsExpiry = array();       ///< When do the restrictions on this page expire?
  60         var $mHasCascadingRestrictions;   ///< Are cascading restrictions in effect on this page?
  61         var $mCascadeSources;  ///< Where are the cascading restrictions coming from on this page?
  62         var $mRestrictionsLoaded = false; ///< Boolean for initialisation on demand
  63         var $mPrefixedText;               ///< Text form including namespace/interwiki, initialised on demand
  64         # Don't change the following default, NS_MAIN is hardcoded in several
  65         # places.  See bug 696.
  66         var $mDefaultNamespace = NS_MAIN; ///< Namespace index when there is no namespace
  67                                           # Zero except in {{transclusion}} tags
  68         var $mWatched = null;             ///< Is $wgUser watching this page? null if unfilled, accessed through userIsWatching()
  69         var $mLength = -1;                ///< The page length, 0 for special pages
  70         var $mRedirect = null;            ///< Is the article at this title a redirect?
  71         var $mNotificationTimestamp = array(); ///< Associative array of user ID -> timestamp/false
  72         var $mBacklinkCache = null; ///< Cache of links to this title
  73         //@}
  74
  75
  76         /**
  77          * Constructor
  78          * @private
  79          */
  80         /* private */ function __construct() {}
  81
  82         /**
  83          * Create a new Title from a prefixed DB key
  84          * @param $key \type{\string} The database key, which has underscores
  85          *      instead of spaces, possibly including namespace and
  86          *      interwiki prefixes
  87          * @return \type{Title} the new object, or NULL on an error
  88          */
  89         public static function newFromDBkey( $key ) {
  90                 $t = new Title();
  91                 $t->mDbkeyform = $key;
  92                 if( $t->secureAndSplit() )
  93                         return $t;
  94                 else
  95                         return NULL;
  96         }
  97
  98         /**
  99          * Create a new Title from text, such as what one would find in a link. De-
 100          * codes any HTML entities in the text.
 101          *
 102          * @param $text             string  The link text; spaces, prefixes, and an
 103          *   initial ':' indicating the main namespace are accepted.
 104          * @param $defaultNamespace int     The namespace to use if none is speci-
 105          *   fied by a prefix.  If you want to force a specific namespace even if
 106          *   $text might begin with a namespace prefix, use makeTitle() or
 107          *   makeTitleSafe().
 108          * @return Title  The new object, or null on an error.
 109          */
 110         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 111                 if( is_object( $text ) ) {
 112                         throw new MWException( 'Title::newFromText given an object' );
 113                 }
 114
 115                 /**
 116                  * Wiki pages often contain multiple links to the same page.
 117                  * Title normalization and parsing can become expensive on
 118                  * pages with many links, so we can save a little time by
 119                  * caching them.
 120                  *
 121                  * In theory these are value objects and won't get changed...
 122                  */
 123                 if( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 124                         return Title::$titleCache[$text];
 125                 }
 126
 127                 /**
 128                  * Convert things like &eacute; &#257; or &#x3017; into real text...
 129                  */
 130                 $filteredText = Sanitizer::decodeCharReferences( $text );
 131
 132                 $t = new Title();
 133                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 134                 $t->mDefaultNamespace = $defaultNamespace;
 135
 136                 static $cachedcount = 0 ;
 137                 if( $t->secureAndSplit() ) {
 138                         if( $defaultNamespace == NS_MAIN ) {
 139                                 if( $cachedcount >= self::CACHE_MAX ) {
 140                                         # Avoid memory leaks on mass operations...
 141                                         Title::$titleCache = array();
 142                                         $cachedcount=0;
 143                                 }
 144                                 $cachedcount++;
 145                                 Title::$titleCache[$text] =& $t;
 146                         }
 147                         return $t;
 148                 } else {
 149                         $ret = NULL;
 150                         return $ret;
 151                 }
 152         }
 153
 154         /**
 155          * Create a new Title from URL-encoded text. Ensures that
 156          * the given title's length does not exceed the maximum.
 157          * @param $url \type{\string} the title, as might be taken from a URL
 158          * @return \type{Title} the new object, or NULL on an error
 159          */
 160         public static function newFromURL( $url ) {
 161                 global $wgLegalTitleChars;
 162                 $t = new Title();
 163
 164                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 165                 # but some URLs used it as a space replacement and they still come
 166                 # from some external search tools.
 167                 if ( strpos( $wgLegalTitleChars, '+' ) === false ) {
 168                         $url = str_replace( '+', ' ', $url );
 169                 }
 170
 171                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 172                 if( $t->secureAndSplit() ) {
 173                         return $t;
 174                 } else {
 175                         return NULL;
 176                 }
 177         }
 178
 179         /**
 180          * Create a new Title from an article ID
 181          *
 182          * @todo This is inefficiently implemented, the page row is requested
 183          *       but not used for anything else
 184          *
 185          * @param $id \type{\int} the page_id corresponding to the Title to create
 186          * @param $flags \type{\int} use GAID_FOR_UPDATE to use master
 187          * @return \type{Title} the new object, or NULL on an error
 188          */
 189         public static function newFromID( $id, $flags = 0 ) {
 190                 $fname = 'Title::newFromID';
 191                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
 192                 $row = $db->selectRow( 'page', array( 'page_namespace', 'page_title' ),
 193                         array( 'page_id' => $id ), $fname );
 194                 if ( $row !== false ) {
 195                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 196                 } else {
 197                         $title = NULL;
 198                 }
 199                 return $title;
 200         }
 201
 202         /**
 203          * Make an array of titles from an array of IDs
 204          * @param $ids \type{\arrayof{\int}} Array of IDs
 205          * @return \type{\arrayof{Title}} Array of Titles
 206          */
 207         public static function newFromIDs( $ids ) {
 208                 if ( !count( $ids ) ) {
 209                         return array();
 210                 }
 211                 $dbr = wfGetDB( DB_SLAVE );
 212                 $res = $dbr->select( 'page', array( 'page_namespace', 'page_title' ),
 213                         'page_id IN (' . $dbr->makeList( $ids ) . ')', __METHOD__ );
 214
 215                 $titles = array();
 216                 foreach( $res as $row ) {
 217                         $titles[] = Title::makeTitle( $row->page_namespace, $row->page_title );
 218                 }
 219                 return $titles;
 220         }
 221
 222         /**
 223          * Make a Title object from a DB row
 224          * @param $row \type{Row} (needs at least page_title,page_namespace)
 225          * @return \type{Title} corresponding Title
 226          */
 227         public static function newFromRow( $row ) {
 228                 $t = self::makeTitle( $row->page_namespace, $row->page_title );
 229
 230                 $t->mArticleID = isset($row->page_id) ? intval($row->page_id) : -1;
 231                 $t->mLength = isset($row->page_len) ? intval($row->page_len) : -1;
 232                 $t->mRedirect = isset($row->page_is_redirect) ? (bool)$row->page_is_redirect : NULL;
 233                 $t->mLatestID = isset($row->page_latest) ? $row->page_latest : false;
 234
 235                 return $t;
 236         }
 237
 238         /**
 239          * Create a new Title from a namespace index and a DB key.
 240          * It's assumed that $ns and $title are *valid*, for instance when
 241          * they came directly from the database or a special page name.
 242          * For convenience, spaces are converted to underscores so that
 243          * eg user_text fields can be used directly.
 244          *
 245          * @param $ns \type{\int} the namespace of the article
 246          * @param $title \type{\string} the unprefixed database key form
 247          * @param $fragment \type{\string} The link fragment (after the "#")
 248          * @return \type{Title} the new object
 249          */
 250         public static function &makeTitle( $ns, $title, $fragment = '' ) {
 251                 $t = new Title();
 252                 $t->mInterwiki = '';
 253                 $t->mFragment = $fragment;
 254                 $t->mNamespace = $ns = intval( $ns );
 255                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 256                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 257                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 258                 $t->mTextform = str_replace( '_', ' ', $title );
 259                 return $t;
 260         }
 261
 262         /**
 263          * Create a new Title from a namespace index and a DB key.
 264          * The parameters will be checked for validity, which is a bit slower
 265          * than makeTitle() but safer for user-provided data.
 266          *
 267          * @param $ns \type{\int} the namespace of the article
 268          * @param $title \type{\string} the database key form
 269          * @param $fragment \type{\string} The link fragment (after the "#")
 270          * @return \type{Title} the new object, or NULL on an error
 271          */
 272         public static function makeTitleSafe( $ns, $title, $fragment = '' ) {
 273                 $t = new Title();
 274                 $t->mDbkeyform = Title::makeName( $ns, $title, $fragment );
 275                 if( $t->secureAndSplit() ) {
 276                         return $t;
 277                 } else {
 278                         return NULL;
 279                 }
 280         }
 281
 282         /**
 283          * Create a new Title for the Main Page
 284          * @return \type{Title} the new object
 285          */
 286         public static function newMainPage() {
 287                 $title = Title::newFromText( wfMsgForContent( 'mainpage' ) );
 288                 // Don't give fatal errors if the message is broken
 289                 if ( !$title ) {
 290                         $title = Title::newFromText( 'Main Page' );
 291                 }
 292                 return $title;
 293         }
 294
 295         /**
 296          * Extract a redirect destination from a string and return the
 297          * Title, or null if the text doesn't contain a valid redirect
 298          * This will only return the very next target, useful for
 299          * the redirect table and other checks that don't need full recursion
 300          *
 301          * @param $text \type{\string} Text with possible redirect
 302          * @return \type{Title} The corresponding Title
 303          */
 304         public static function newFromRedirect( $text ) {
 305                 return self::newFromRedirectInternal( $text );
 306         }
 307
 308         /**
 309          * Extract a redirect destination from a string and return the
 310          * Title, or null if the text doesn't contain a valid redirect
 311          * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
 312          * in order to provide (hopefully) the Title of the final destination instead of another redirect
 313          *
 314          * @param $text \type{\string} Text with possible redirect
 315          * @return \type{Title} The corresponding Title
 316          */
 317         public static function newFromRedirectRecurse( $text ) {
 318                 $titles = self::newFromRedirectArray( $text );
 319                 return $titles ? array_pop( $titles ) : null;
 320         }
 321
 322         /**
 323          * Extract a redirect destination from a string and return an
 324          * array of Titles, or null if the text doesn't contain a valid redirect
 325          * The last element in the array is the final destination after all redirects
 326          * have been resolved (up to $wgMaxRedirects times)
 327          *
 328          * @param $text \type{\string} Text with possible redirect
 329          * @return \type{\array} Array of Titles, with the destination last
 330          */
 331         public static function newFromRedirectArray( $text ) {
 332                 global $wgMaxRedirects;
 333                 // are redirects disabled?
 334                 if( $wgMaxRedirects < 1 )
 335                         return null;
 336                 $title = self::newFromRedirectInternal( $text );
 337                 if( is_null( $title ) )
 338                         return null;
 339                 // recursive check to follow double redirects
 340                 $recurse = $wgMaxRedirects;
 341                 $titles = array( $title );
 342                 while( --$recurse >= 0 ) {
 343                         if( $title->isRedirect() ) {
 344                                 $article = new Article( $title, 0 );
 345                                 $newtitle = $article->getRedirectTarget();
 346                         } else {
 347                                 break;
 348                         }
 349                         // Redirects to some special pages are not permitted
 350                         if( $newtitle instanceOf Title && $newtitle->isValidRedirectTarget() ) {
 351                                 // the new title passes the checks, so make that our current title so that further recursion can be checked
 352                                 $title = $newtitle;
 353                                 $titles[] = $newtitle;
 354                         } else {
 355                                 break;
 356                         }
 357                 }
 358                 return $titles;
 359         }
 360
 361         /**
 362          * Really extract the redirect destination
 363          * Do not call this function directly, use one of the newFromRedirect* functions above
 364          *
 365          * @param $text \type{\string} Text with possible redirect
 366          * @return \type{Title} The corresponding Title
 367          */
 368         protected static function newFromRedirectInternal( $text ) {
 369                 $redir = MagicWord::get( 'redirect' );
 370                 $text = trim($text);
 371                 if( $redir->matchStartAndRemove( $text ) ) {
 372                         // Extract the first link and see if it's usable
 373                         // Ensure that it really does come directly after #REDIRECT
 374                         // Some older redirects included a colon, so don't freak about that!
 375                         $m = array();
 376                         if( preg_match( '!^\s*:?\s*\[{2}(.*?)(?:\|.*?)?\]{2}!', $text, $m ) ) {
 377                                 // Strip preceding colon used to "escape" categories, etc.
 378                                 // and URL-decode links
 379                                 if( strpos( $m[1], '%' ) !== false ) {
 380                                         // Match behavior of inline link parsing here;
 381                                         // don't interpret + as " " most of the time!
 382                                         // It might be safe to just use rawurldecode instead, though.
 383                                         $m[1] = urldecode( ltrim( $m[1], ':' ) );
 384                                 }
 385                                 $title = Title::newFromText( $m[1] );
 386                                 // If the title is a redirect to bad special pages or is invalid, return null
 387                                 if( !$title instanceof Title || !$title->isValidRedirectTarget() ) {
 388                                         return null;
 389                                 }
 390                                 return $title;
 391                         }
 392                 }
 393                 return null;
 394         }
 395
 396 #----------------------------------------------------------------------------
 397 #       Static functions
 398 #----------------------------------------------------------------------------
 399
 400         /**
 401          * Get the prefixed DB key associated with an ID
 402          * @param $id \type{\int} the page_id of the article
 403          * @return \type{Title} an object representing the article, or NULL
 404          *      if no such article was found
 405          */
 406         public static function nameOf( $id ) {
 407                 $dbr = wfGetDB( DB_SLAVE );
 408
 409                 $s = $dbr->selectRow( 'page',
 410                         array( 'page_namespace','page_title' ),
 411                         array( 'page_id' => $id ),
 412                         __METHOD__ );
 413                 if ( $s === false ) { return NULL; }
 414
 415                 $n = self::makeName( $s->page_namespace, $s->page_title );
 416                 return $n;
 417         }
 418
 419         /**
 420          * Get a regex character class describing the legal characters in a link
 421          * @return \type{\string} the list of characters, not delimited
 422          */
 423         public static function legalChars() {
 424                 global $wgLegalTitleChars;
 425                 return $wgLegalTitleChars;
 426         }
 427
 428         /**
 429          * Get a string representation of a title suitable for
 430          * including in a search index
 431          *
 432          * @param $ns \type{\int} a namespace index
 433          * @param $title \type{\string} text-form main part
 434          * @return \type{\string} a stripped-down title string ready for the
 435          *      search index
 436          */
 437         public static function indexTitle( $ns, $title ) {
 438                 global $wgContLang;
 439
 440                 $lc = SearchEngine::legalSearchChars() . '&#;';
 441                 $t = $wgContLang->stripForSearch( $title );
 442                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 443                 $t = $wgContLang->lc( $t );
 444
 445                 # Handle 's, s'
 446                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 447                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 448
 449                 $t = preg_replace( "/\\s+/", ' ', $t );
 450
 451                 if ( $ns == NS_FILE ) {
 452                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 453                 }
 454                 return trim( $t );
 455         }
 456
 457         /*
 458          * Make a prefixed DB key from a DB key and a namespace index
 459          * @param $ns \type{\int} numerical representation of the namespace
 460          * @param $title \type{\string} the DB key form the title
 461          * @param $fragment \type{\string} The link fragment (after the "#")
 462          * @return \type{\string} the prefixed form of the title
 463          */
 464         public static function makeName( $ns, $title, $fragment = '' ) {
 465                 global $wgContLang;
 466
 467                 $namespace = $wgContLang->getNsText( $ns );
 468                 $name = $namespace == '' ? $title : "$namespace:$title";
 469                 if ( strval( $fragment ) != '' ) {
 470                         $name .= '#' . $fragment;
 471                 }
 472                 return $name;
 473         }
 474
 475         /**
 476          * Returns the URL associated with an interwiki prefix
 477          * @param $key \type{\string} the interwiki prefix (e.g. "MeatBall")
 478          * @return \type{\string} the associated URL, containing "$1",
 479          *      which should be replaced by an article title
 480          * @static (arguably)
 481          * @deprecated See Interwiki class
 482          */
 483         public function getInterwikiLink( $key )  {
 484                 return Interwiki::fetch( $key )->getURL( );
 485         }
 486
 487         /**
 488          * Determine whether the object refers to a page within
 489          * this project.
 490          *
 491          * @return \type{\bool} TRUE if this is an in-project interwiki link
 492          *      or a wikilink, FALSE otherwise
 493          */
 494         public function isLocal() {
 495                 if ( $this->mInterwiki != '' ) {
 496                         return Interwiki::fetch( $this->mInterwiki )->isLocal();
 497                 } else {
 498                         return true;
 499                 }
 500         }
 501
 502         /**
 503          * Determine whether the object refers to a page within
 504          * this project and is transcludable.
 505          *
 506          * @return \type{\bool} TRUE if this is transcludable
 507          */
 508         public function isTrans() {
 509                 if ($this->mInterwiki == '')
 510                         return false;
 511
 512                 return Interwiki::fetch( $this->mInterwiki )->isTranscludable();
 513         }
 514
 515         /**
 516          * Escape a text fragment, say from a link, for a URL
 517          */
 518         static function escapeFragmentForURL( $fragment ) {
 519                 global $wgEnforceHtmlIds;
 520                 # Note that we don't urlencode the fragment.  urlencoded Unicode
 521                 # fragments appear not to work in IE (at least up to 7) or in at least
 522                 # one version of Opera 9.x.  The W3C validator, for one, doesn't seem
 523                 # to care if they aren't encoded.
 524                 return Sanitizer::escapeId( $fragment,
 525                         $wgEnforceHtmlIds ? 'noninitial' : 'xml' );
 526         }
 527
 528 #----------------------------------------------------------------------------
 529 #       Other stuff
 530 #----------------------------------------------------------------------------
 531
 532         /** Simple accessors */
 533         /**
 534          * Get the text form (spaces not underscores) of the main part
 535          * @return \type{\string} Main part of the title
 536          */
 537         public function getText() { return $this->mTextform; }
 538         /**
 539          * Get the URL-encoded form of the main part
 540          * @return \type{\string} Main part of the title, URL-encoded
 541          */
 542         public function getPartialURL() { return $this->mUrlform; }
 543         /**
 544          * Get the main part with underscores
 545          * @return \type{\string} Main part of the title, with underscores
 546          */
 547         public function getDBkey() { return $this->mDbkeyform; }
 548         /**
 549          * Get the namespace index, i.e.\ one of the NS_xxxx constants.
 550          * @return \type{\int} Namespace index
 551          */
 552         public function getNamespace() { return $this->mNamespace; }
 553         /**
 554          * Get the namespace text
 555          * @return \type{\string} Namespace text
 556          */
 557         public function getNsText() {
 558                 global $wgCanonicalNamespaceNames;
 559
 560                 if ( '' != $this->mInterwiki ) {
 561                         // This probably shouldn't even happen. ohh man, oh yuck.
 562                         // But for interwiki transclusion it sometimes does.
 563                         // Shit. Shit shit shit.
 564                         //
 565                         // Use the canonical namespaces if possible to try to
 566                         // resolve a foreign namespace.
 567                         if( isset( $wgCanonicalNamespaceNames[$this->mNamespace] ) ) {
 568                                 return $wgCanonicalNamespaceNames[$this->mNamespace];
 569                         }
 570                 }
 571
 572                 return $this->getNsTextInternal( $this->mNamespace );
 573         }
 574
 575         function getNsTextInternal( $namespace ) {
 576                 global $wgContLang, $wgRequest, $wgTitle, $wgSlowGenderAliases;
 577                 if( $namespace === NS_USER || $namespace === NS_USER_TALK ) {
 578                         static $gender = null;
 579
 580                         $name = $this->getBaseText();
 581                         if( !isset($gender[$name] ) ) {
 582                                 $gender[$name] = User::getDefaultOption( 'gender' );
 583
 584                                 // wgTitle may not be defined
 585                                 $mytitle = isset( $wgTitle ) ? $wgTitle : Title::newFromText( $wgRequest->getVal( 'title' ) );
 586
 587                                 // Check stuff
 588                                 if ( $wgSlowGenderAliases ||
 589                                      // Needs to be checked always to produce desired
 590                                      // effect when viewing user pages
 591                                      ( $mytitle && $name === $mytitle->getBaseText() ) ) {
 592
 593                                         $user = User::newFromName( $name );
 594                                         if ( $user ) $gender[$name] = $user->getOption( 'gender' );
 595                                 }
 596                         }
 597
 598                         return $wgContLang->getGenderNsText( $this->mNamespace, $gender[$name] );
 599                 }
 600                 return $wgContLang->getNsText( $this->mNamespace );
 601         }
 602         /**
 603          * Get the DB key with the initial letter case as specified by the user
 604          * @return \type{\string} DB key
 605          */
 606         function getUserCaseDBKey() {
 607                 return $this->mUserCaseDBKey;
 608         }
 609         /**
 610          * Get the namespace text of the subject (rather than talk) page
 611          * @return \type{\string} Namespace text
 612          */
 613         public function getSubjectNsText() {
 614                 return $this->getNsTextInternal( MWNamespace::getSubject( $this->mNamespace ) );
 615         }
 616         /**
 617          * Get the namespace text of the talk page
 618          * @return \type{\string} Namespace text
 619          */
 620         public function getTalkNsText() {
 621                 return $this->getNsTextInternal( MWNamespace::getTalk( $this->mNamespace ) );
 622         }
 623         /**
 624          * Could this title have a corresponding talk page?
 625          * @return \type{\bool} TRUE or FALSE
 626          */
 627         public function canTalk() {
 628                 return( MWNamespace::canTalk( $this->mNamespace ) );
 629         }
 630         /**
 631          * Get the interwiki prefix (or null string)
 632          * @return \type{\string} Interwiki prefix
 633          */
 634         public function getInterwiki() { return $this->mInterwiki; }
 635         /**
 636          * Get the Title fragment (i.e.\ the bit after the #) in text form
 637          * @return \type{\string} Title fragment
 638          */
 639         public function getFragment() { return $this->mFragment; }
 640         /**
 641          * Get the fragment in URL form, including the "#" character if there is one
 642          * @return \type{\string} Fragment in URL form
 643          */
 644         public function getFragmentForURL() {
 645                 if ( $this->mFragment == '' ) {
 646                         return '';
 647                 } else {
 648                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
 649                 }
 650         }
 651         /**
 652          * Get the default namespace index, for when there is no namespace
 653          * @return \type{\int} Default namespace index
 654          */
 655         public function getDefaultNamespace() { return $this->mDefaultNamespace; }
 656
 657         /**
 658          * Get title for search index
 659          * @return \type{\string} a stripped-down title string ready for the
 660          *      search index
 661          */
 662         public function getIndexTitle() {
 663                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 664         }
 665
 666         /**
 667          * Get the prefixed database key form
 668          * @return \type{\string} the prefixed title, with underscores and
 669          *      any interwiki and namespace prefixes
 670          */
 671         public function getPrefixedDBkey() {
 672                 $s = $this->prefix( $this->mDbkeyform );
 673                 $s = str_replace( ' ', '_', $s );
 674                 return $s;
 675         }
 676
 677         /**
 678          * Get the prefixed title with spaces.
 679          * This is the form usually used for display
 680          * @return \type{\string} the prefixed title, with spaces
 681          */
 682         public function getPrefixedText() {
 683                 if ( empty( $this->mPrefixedText ) ) { // FIXME: bad usage of empty() ?
 684                         $s = $this->prefix( $this->mTextform );
 685                         $s = str_replace( '_', ' ', $s );
 686                         $this->mPrefixedText = $s;
 687                 }
 688                 return $this->mPrefixedText;
 689         }
 690
 691         /**
 692          * Get the prefixed title with spaces, plus any fragment
 693          * (part beginning with '#')
 694          * @return \type{\string} the prefixed title, with spaces and
 695          *      the fragment, including '#'
 696          */
 697         public function getFullText() {
 698                 $text = $this->getPrefixedText();
 699                 if( '' != $this->mFragment ) {
 700                         $text .= '#' . $this->mFragment;
 701                 }
 702                 return $text;
 703         }
 704
 705         /**
 706          * Get the base name, i.e. the leftmost parts before the /
 707          * @return \type{\string} Base name
 708          */
 709         public function getBaseText() {
 710                 if( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
 711                         return $this->getText();
 712                 }
 713
 714                 $parts = explode( '/', $this->getText() );
 715                 # Don't discard the real title if there's no subpage involved
 716                 if( count( $parts ) > 1 )
 717                         unset( $parts[ count( $parts ) - 1 ] );
 718                 return implode( '/', $parts );
 719         }
 720
 721         /**
 722          * Get the lowest-level subpage name, i.e. the rightmost part after /
 723          * @return \type{\string} Subpage name
 724          */
 725         public function getSubpageText() {
 726                 if( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
 727                         return( $this->mTextform );
 728                 }
 729                 $parts = explode( '/', $this->mTextform );
 730                 return( $parts[ count( $parts ) - 1 ] );
 731         }
 732
 733         /**
 734          * Get a URL-encoded form of the subpage text
 735          * @return \type{\string} URL-encoded subpage name
 736          */
 737         public function getSubpageUrlForm() {
 738                 $text = $this->getSubpageText();
 739                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
 740                 return( $text );
 741         }
 742
 743         /**
 744          * Get a URL-encoded title (not an actual URL) including interwiki
 745          * @return \type{\string} the URL-encoded form
 746          */
 747         public function getPrefixedURL() {
 748                 $s = $this->prefix( $this->mDbkeyform );
 749                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
 750                 return $s;
 751         }
 752
 753         /**
 754          * Get a real URL referring to this title, with interwiki link and
 755          * fragment
 756          *
 757          * @param $query \twotypes{\string,\array} an optional query string, not used for interwiki
 758          *   links. Can be specified as an associative array as well, e.g.,
 759          *   array( 'action' => 'edit' ) (keys and values will be URL-escaped).
 760          * @param $variant \type{\string} language variant of url (for sr, zh..)
 761          * @return \type{\string} the URL
 762          */
 763         public function getFullURL( $query = '', $variant = false ) {
 764                 global $wgContLang, $wgServer, $wgRequest;
 765
 766                 if( is_array( $query ) ) {
 767                         $query = wfArrayToCGI( $query );
 768                 }
 769
 770                 $interwiki = Interwiki::fetch( $this->mInterwiki );
 771                 if ( !$interwiki ) {
 772                         $url = $this->getLocalUrl( $query, $variant );
 773
 774                         // Ugly quick hack to avoid duplicate prefixes (bug 4571 etc)
 775                         // Correct fix would be to move the prepending elsewhere.
 776                         if ($wgRequest->getVal('action') != 'render') {
 777                                 $url = $wgServer . $url;
 778                         }
 779                 } else {
 780                         $baseUrl = $interwiki->getURL( );
 781
 782                         $namespace = wfUrlencode( $this->getNsText() );
 783                         if ( '' != $namespace ) {
 784                                 # Can this actually happen? Interwikis shouldn't be parsed.
 785                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
 786                                 $namespace .= ':';
 787                         }
 788                         $url = str_replace( '$1', $namespace . $this->mUrlform, $baseUrl );
 789                         $url = wfAppendQuery( $url, $query );
 790                 }
 791
 792                 # Finally, add the fragment.
 793                 $url .= $this->getFragmentForURL();
 794
 795                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
 796                 return $url;
 797         }
 798
 799         /**
 800          * Get a URL with no fragment or server name.  If this page is generated
 801          * with action=render, $wgServer is prepended.
 802          * @param mixed $query an optional query string; if not specified,
 803          *       $wgArticlePath will be used.  Can be specified as an associative array
 804          *   as well, e.g., array( 'action' => 'edit' ) (keys and values will be
 805          *   URL-escaped).
 806          * @param $variant \type{\string} language variant of url (for sr, zh..)
 807          * @return \type{\string} the URL
 808          */
 809         public function getLocalURL( $query = '', $variant = false ) {
 810                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
 811                 global $wgVariantArticlePath, $wgContLang, $wgUser;
 812
 813                 if( is_array( $query ) ) {
 814                         $query = wfArrayToCGI( $query );
 815                 }
 816
 817                 // internal links should point to same variant as current page (only anonymous users)
 818                 if($variant == false && $wgContLang->hasVariants() && !$wgUser->isLoggedIn()){
 819                         $pref = $wgContLang->getPreferredVariant(false);
 820                         if($pref != $wgContLang->getCode())
 821                                 $variant = $pref;
 822                 }
 823
 824                 if ( $this->isExternal() ) {
 825                         $url = $this->getFullURL();
 826                         if ( $query ) {
 827                                 // This is currently only used for edit section links in the
 828                                 // context of interwiki transclusion. In theory we should
 829                                 // append the query to the end of any existing query string,
 830                                 // but interwiki transclusion is already broken in that case.
 831                                 $url .= "?$query";
 832                         }
 833                 } else {
 834                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 835                         if ( $query == '' ) {
 836                                 if( $variant != false && $wgContLang->hasVariants() ) {
 837                                         if( $wgVariantArticlePath == false ) {
 838                                                 $variantArticlePath =  "$wgScript?title=$1&variant=$2"; // default
 839                                         } else {
 840                                                 $variantArticlePath = $wgVariantArticlePath;
 841                                         }
 842                                         $url = str_replace( '$2', urlencode( $variant ), $variantArticlePath );
 843                                         $url = str_replace( '$1', $dbkey, $url  );
 844                                 } else {
 845                                         $url = str_replace( '$1', $dbkey, $wgArticlePath );
 846                                 }
 847                         } else {
 848                                 global $wgActionPaths;
 849                                 $url = false;
 850                                 $matches = array();
 851                                 if( !empty( $wgActionPaths ) &&
 852                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
 853                                 {
 854                                         $action = urldecode( $matches[2] );
 855                                         if( isset( $wgActionPaths[$action] ) ) {
 856                                                 $query = $matches[1];
 857                                                 if( isset( $matches[4] ) ) $query .= $matches[4];
 858                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
 859                                                 if( $query != '' ) {
 860                                                         $url = wfAppendQuery( $url, $query );
 861                                                 }
 862                                         }
 863                                 }
 864                                 if ( $url === false ) {
 865                                         if ( $query == '-' ) {
 866                                                 $query = '';
 867                                         }
 868                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
 869                                 }
 870                         }
 871
 872                         // FIXME: this causes breakage in various places when we
 873                         // actually expected a local URL and end up with dupe prefixes.
 874                         if ($wgRequest->getVal('action') == 'render') {
 875                                 $url = $wgServer . $url;
 876                         }
 877                 }
 878                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
 879                 return $url;
 880         }
 881
 882         /**
 883          * Get a URL that's the simplest URL that will be valid to link, locally,
 884          * to the current Title.  It includes the fragment, but does not include
 885          * the server unless action=render is used (or the link is external).  If
 886          * there's a fragment but the prefixed text is empty, we just return a link
 887          * to the fragment.
 888          *
 889          * @param $query \type{\arrayof{\string}} An associative array of key => value pairs for the
 890          *   query string.  Keys and values will be escaped.
 891          * @param $variant \type{\string} Language variant of URL (for sr, zh..).  Ignored
 892          *   for external links.  Default is "false" (same variant as current page,
 893          *   for anonymous users).
 894          * @return \type{\string} the URL
 895          */
 896         public function getLinkUrl( $query = array(), $variant = false ) {
 897                 if( !is_array( $query ) ) {
 898                         throw new MWException( 'Title::getLinkUrl passed a non-array for '.
 899                         '$query' );
 900                 }
 901                 if( $this->isExternal() ) {
 902                         return $this->getFullURL( $query );
 903                 } elseif( $this->getPrefixedText() === ''
 904                 and $this->getFragment() !== '' ) {
 905                         return $this->getFragmentForURL();
 906                 } else {
 907                         return $this->getLocalURL( $query, $variant )
 908                                 . $this->getFragmentForURL();
 909                 }
 910         }
 911
 912         /**
 913          * Get an HTML-escaped version of the URL form, suitable for
 914          * using in a link, without a server name or fragment
 915          * @param $query \type{\string} an optional query string
 916          * @return \type{\string} the URL
 917          */
 918         public function escapeLocalURL( $query = '' ) {
 919                 return htmlspecialchars( $this->getLocalURL( $query ) );
 920         }
 921
 922         /**
 923          * Get an HTML-escaped version of the URL form, suitable for
 924          * using in a link, including the server name and fragment
 925          *
 926          * @param $query \type{\string} an optional query string
 927          * @return \type{\string} the URL
 928          */
 929         public function escapeFullURL( $query = '' ) {
 930                 return htmlspecialchars( $this->getFullURL( $query ) );
 931         }
 932
 933         /**
 934          * Get the URL form for an internal link.
 935          * - Used in various Squid-related code, in case we have a different
 936          * internal hostname for the server from the exposed one.
 937          *
 938          * @param $query \type{\string} an optional query string
 939          * @param $variant \type{\string} language variant of url (for sr, zh..)
 940          * @return \type{\string} the URL
 941          */
 942         public function getInternalURL( $query = '', $variant = false ) {
 943                 global $wgInternalServer;
 944                 $url = $wgInternalServer . $this->getLocalURL( $query, $variant );
 945                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
 946                 return $url;
 947         }
 948
 949         /**
 950          * Get the edit URL for this Title
 951          * @return \type{\string} the URL, or a null string if this is an
 952          *      interwiki link
 953          */
 954         public function getEditURL() {
 955                 if ( '' != $this->mInterwiki ) { return ''; }
 956                 $s = $this->getLocalURL( 'action=edit' );
 957
 958                 return $s;
 959         }
 960
 961         /**
 962          * Get the HTML-escaped displayable text form.
 963          * Used for the title field in <a> tags.
 964          * @return \type{\string} the text, including any prefixes
 965          */
 966         public function getEscapedText() {
 967                 return htmlspecialchars( $this->getPrefixedText() );
 968         }
 969
 970         /**
 971          * Is this Title interwiki?
 972          * @return \type{\bool}
 973          */
 974         public function isExternal() { return ( '' != $this->mInterwiki ); }
 975
 976         /**
 977          * Is this page "semi-protected" - the *only* protection is autoconfirm?
 978          *
 979          * @param @action \type{\string} Action to check (default: edit)
 980          * @return \type{\bool}
 981          */
 982         public function isSemiProtected( $action = 'edit' ) {
 983                 if( $this->exists() ) {
 984                         $restrictions = $this->getRestrictions( $action );
 985                         if( count( $restrictions ) > 0 ) {
 986                                 foreach( $restrictions as $restriction ) {
 987                                         if( strtolower( $restriction ) != 'autoconfirmed' )
 988                                                 return false;
 989                                 }
 990                         } else {
 991                                 # Not protected
 992                                 return false;
 993                         }
 994                         return true;
 995                 } else {
 996                         # If it doesn't exist, it can't be protected
 997                         return false;
 998                 }
 999         }
1000
1001         /**
1002          * Does the title correspond to a protected article?
1003          * @param $what \type{\string} the action the page is protected from,
1004          * by default checks move and edit
1005          * @return \type{\bool}
1006          */
1007         public function isProtected( $action = '' ) {
1008                 global $wgRestrictionLevels, $wgRestrictionTypes;
1009
1010                 # Special pages have inherent protection
1011                 if( $this->getNamespace() == NS_SPECIAL )
1012                         return true;
1013
1014                 # Check regular protection levels
1015                 foreach( $wgRestrictionTypes as $type ){
1016                         if( $action == $type || $action == '' ) {
1017                                 $r = $this->getRestrictions( $type );
1018                                 foreach( $wgRestrictionLevels as $level ) {
1019                                         if( in_array( $level, $r ) && $level != '' ) {
1020                                                 return true;
1021                                         }
1022                                 }
1023                         }
1024                 }
1025
1026                 return false;
1027         }
1028
1029         /**
1030          * Is $wgUser watching this page?
1031          * @return \type{\bool}
1032          */
1033         public function userIsWatching() {
1034                 global $wgUser;
1035
1036                 if ( is_null( $this->mWatched ) ) {
1037                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn()) {
1038                                 $this->mWatched = false;
1039                         } else {
1040                                 $this->mWatched = $wgUser->isWatched( $this );
1041                         }
1042                 }
1043                 return $this->mWatched;
1044         }
1045
1046         /**
1047          * Can $wgUser perform $action on this page?
1048          * This skips potentially expensive cascading permission checks.
1049          *
1050          * Suitable for use for nonessential UI controls in common cases, but
1051          * _not_ for functional access control.
1052          *
1053          * May provide false positives, but should never provide a false negative.
1054          *
1055          * @param $action \type{\string} action that permission needs to be checked for
1056          * @return \type{\bool}
1057          */
1058         public function quickUserCan( $action ) {
1059                 return $this->userCan( $action, false );
1060         }
1061
1062         /**
1063          * Determines if $wgUser is unable to edit this page because it has been protected
1064          * by $wgNamespaceProtection.
1065          *
1066          * @return \type{\bool}
1067          */
1068         public function isNamespaceProtected() {
1069                 global $wgNamespaceProtection, $wgUser;
1070                 if( isset( $wgNamespaceProtection[ $this->mNamespace ] ) ) {
1071                         foreach( (array)$wgNamespaceProtection[ $this->mNamespace ] as $right ) {
1072                                 if( $right != '' && !$wgUser->isAllowed( $right ) )
1073                                         return true;
1074                         }
1075                 }
1076                 return false;
1077         }
1078
1079         /**
1080          * Can $wgUser perform $action on this page?
1081          * @param $action \type{\string} action that permission needs to be checked for
1082          * @param $doExpensiveQueries \type{\bool} Set this to false to avoid doing unnecessary queries.
1083          * @return \type{\bool}
1084          */
1085         public function userCan( $action, $doExpensiveQueries = true ) {
1086                 global $wgUser;
1087                 return ($this->getUserPermissionsErrorsInternal( $action, $wgUser, $doExpensiveQueries, true ) === array());
1088         }
1089
1090         /**
1091          * Can $user perform $action on this page?
1092          *
1093          * FIXME: This *does not* check throttles (User::pingLimiter()).
1094          *
1095          * @param $action \type{\string}action that permission needs to be checked for
1096          * @param $user \type{User} user to check
1097          * @param $doExpensiveQueries \type{\bool} Set this to false to avoid doing unnecessary queries.
1098          * @param $ignoreErrors \type{\arrayof{\string}} Set this to a list of message keys whose corresponding errors may be ignored.
1099          * @return \type{\array} Array of arrays of the arguments to wfMsg to explain permissions problems.
1100          */
1101         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1102                 if( !StubObject::isRealObject( $user ) ) {
1103                         //Since StubObject is always used on globals, we can unstub $wgUser here and set $user = $wgUser
1104                         global $wgUser;
1105                         $wgUser->_unstub( '', 5 );
1106                         $user = $wgUser;
1107                 }
1108                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1109
1110                 global $wgContLang;
1111                 global $wgLang;
1112                 global $wgEmailConfirmToEdit;
1113
1114                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() && $action != 'createaccount' ) {
1115                         $errors[] = array( 'confirmedittext' );
1116                 }
1117
1118                 // Edit blocks should not affect reading. Account creation blocks handled at userlogin.
1119                 if ( $action != 'read' && $action != 'createaccount' && $user->isBlockedFrom( $this ) ) {
1120                         $block = $user->mBlock;
1121
1122                         // This is from OutputPage::blockedPage
1123                         // Copied at r23888 by werdna
1124
1125                         $id = $user->blockedBy();
1126                         $reason = $user->blockedFor();
1127                         if( $reason == '' ) {
1128                                 $reason = wfMsg( 'blockednoreason' );
1129                         }
1130                         $ip = wfGetIP();
1131
1132                         if ( is_numeric( $id ) ) {
1133                                 $name = User::whoIs( $id );
1134                         } else {
1135                                 $name = $id;
1136                         }
1137
1138                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1139                         $blockid = $block->mId;
1140                         $blockExpiry = $user->mBlock->mExpiry;
1141                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $user->mBlock->mTimestamp ), true );
1142
1143                         if ( $blockExpiry == 'infinity' ) {
1144                                 // Entry in database (table ipblocks) is 'infinity' but 'ipboptions' uses 'infinite' or 'indefinite'
1145                                 $scBlockExpiryOptions = wfMsg( 'ipboptions' );
1146
1147                                 foreach ( explode( ',', $scBlockExpiryOptions ) as $option ) {
1148                                         if ( strpos( $option, ':' ) == false )
1149                                                 continue;
1150
1151                                         list ($show, $value) = explode( ":", $option );
1152
1153                                         if ( $value == 'infinite' || $value == 'indefinite' ) {
1154                                                 $blockExpiry = $show;
1155                                                 break;
1156                                         }
1157                                 }
1158                         } else {
1159                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1160                         }
1161
1162                         $intended = $user->mBlock->mAddress;
1163
1164                         $errors[] = array( ($block->mAuto ? 'autoblockedtext' : 'blockedtext'), $link, $reason, $ip, $name,
1165                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
1166                 }
1167
1168                 // Remove the errors being ignored.
1169
1170                 foreach( $errors as $index => $error ) {
1171                         $error_key = is_array($error) ? $error[0] : $error;
1172
1173                         if (in_array( $error_key, $ignoreErrors )) {
1174                                 unset($errors[$index]);
1175                         }
1176                 }
1177
1178                 return $errors;
1179         }
1180
1181         /**
1182          * Can $user perform $action on this page? This is an internal function,
1183          * which checks ONLY that previously checked by userCan (i.e. it leaves out
1184          * checks on wfReadOnly() and blocks)
1185          *
1186          * @param $action \type{\string} action that permission needs to be checked for
1187          * @param $user \type{User} user to check
1188          * @param $doExpensiveQueries \type{\bool} Set this to false to avoid doing unnecessary queries.
1189          * @param $short \type{\bool} Set this to true to stop after the first permission error.
1190          * @return \type{\array} Array of arrays of the arguments to wfMsg to explain permissions problems.
1191          */
1192         private function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries=true, $short=false ) {
1193                 wfProfileIn( __METHOD__ );
1194
1195                 $errors = array();
1196
1197                 // First stop is permissions checks, which fail most often, and which are easiest to test.
1198                 if ( $action == 'move' ) {
1199                         if( !$user->isAllowed( 'move-rootuserpages' )
1200                                         && $this->getNamespace() == NS_USER && !$this->isSubpage() )
1201                         {
1202                                 // Show user page-specific message only if the user can move other pages
1203                                 $errors[] = array( 'cant-move-user-page' );
1204                         }
1205
1206                         // Check if user is allowed to move files if it's a file
1207                         if( $this->getNamespace() == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1208                                 $errors[] = array( 'movenotallowedfile' );
1209                         }
1210
1211                         if( !$user->isAllowed( 'move' ) ) {
1212                                 // User can't move anything
1213                                 $errors[] = $user->isAnon() ? array ( 'movenologintext' ) : array ('movenotallowed');
1214                         }
1215                 } elseif ( $action == 'create' ) {
1216                         if( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1217                                 ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) )
1218                         {
1219                                 $errors[] = $user->isAnon() ? array ('nocreatetext') : array ('nocreate-loggedin');
1220                         }
1221                 } elseif( $action == 'move-target' ) {
1222                         if( !$user->isAllowed( 'move' ) ) {
1223                                 // User can't move anything
1224                                 $errors[] = $user->isAnon() ? array ( 'movenologintext' ) : array ('movenotallowed');
1225                         } elseif( !$user->isAllowed( 'move-rootuserpages' )
1226                                 && $this->getNamespace() == NS_USER && !$this->isSubpage() )
1227                         {
1228                                 // Show user page-specific message only if the user can move other pages
1229                                 $errors[] = array( 'cant-move-to-user-page' );
1230                         }
1231                 } elseif( !$user->isAllowed( $action ) ) {
1232                         $return = null;
1233                         $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
1234                                 User::getGroupsWithPermission( $action ) );
1235                         if( $groups ) {
1236                                 $return = array( 'badaccess-groups',
1237                                         array( implode( ', ', $groups ), count( $groups ) ) );
1238                         } else {
1239                                 $return = array( "badaccess-group0" );
1240                         }
1241                         $errors[] = $return;
1242                 }
1243
1244                 # Short-circuit point
1245                 if( $short && count($errors) > 0 ) {
1246                         wfProfileOut( __METHOD__ );
1247                         return $errors;
1248                 }
1249
1250                 // Use getUserPermissionsErrors instead
1251                 if( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1252                         wfProfileOut( __METHOD__ );
1253                         return $result ? array() : array( array( 'badaccess-group0' ) );
1254                 }
1255                 // Check getUserPermissionsErrors hook
1256                 if( !wfRunHooks( 'getUserPermissionsErrors', array(&$this,&$user,$action,&$result) ) ) {
1257                         if( is_array($result) && count($result) && !is_array($result[0]) )
1258                                 $errors[] = $result; # A single array representing an error
1259                         else if( is_array($result) && is_array($result[0]) )
1260                                 $errors = array_merge( $errors, $result ); # A nested array representing multiple errors
1261                         else if( $result !== '' && is_string($result) )
1262                                 $errors[] = array($result); # A string representing a message-id
1263                         else if( $result === false )
1264                                 $errors[] = array('badaccess-group0'); # a generic "We don't want them to do that"
1265                 }
1266                 # Short-circuit point
1267                 if( $short && count($errors) > 0 ) {
1268                         wfProfileOut( __METHOD__ );
1269                         return $errors;
1270                 }
1271                 // Check getUserPermissionsErrorsExpensive hook
1272                 if( $doExpensiveQueries && !wfRunHooks( 'getUserPermissionsErrorsExpensive', array(&$this,&$user,$action,&$result) ) ) {
1273                         if( is_array($result) && count($result) && !is_array($result[0]) )
1274                                 $errors[] = $result; # A single array representing an error
1275                         else if( is_array($result) && is_array($result[0]) )
1276                                 $errors = array_merge( $errors, $result ); # A nested array representing multiple errors
1277                         else if( $result !== '' && is_string($result) )
1278                                 $errors[] = array($result); # A string representing a message-id
1279                         else if( $result === false )
1280                                 $errors[] = array('badaccess-group0'); # a generic "We don't want them to do that"
1281                 }
1282                 # Short-circuit point
1283                 if( $short && count($errors) > 0 ) {
1284                         wfProfileOut( __METHOD__ );
1285                         return $errors;
1286                 }
1287
1288                 # Only 'createaccount' and 'execute' can be performed on
1289                 # special pages, which don't actually exist in the DB.
1290                 $specialOKActions = array( 'createaccount', 'execute' );
1291                 if( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions) ) {
1292                         $errors[] = array('ns-specialprotected');
1293                 }
1294
1295                 # Check $wgNamespaceProtection for restricted namespaces
1296                 if( $this->isNamespaceProtected() ) {
1297                         $ns = $this->getNamespace() == NS_MAIN ?
1298                                 wfMsg( 'nstab-main' ) : $this->getNsText();
1299                         $errors[] = NS_MEDIAWIKI == $this->mNamespace ?
1300                                 array('protectedinterface') : array( 'namespaceprotected',  $ns );
1301                 }
1302
1303                 # Protect css/js subpages of user pages
1304                 # XXX: this might be better using restrictions
1305                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssJsSubpage() from working
1306                 if( $this->isCssJsSubpage() && !$user->isAllowed('editusercssjs')
1307                         && !preg_match('/^'.preg_quote($user->getName(), '/').'\//', $this->mTextform) )
1308                 {
1309                         $errors[] = array('customcssjsprotected');
1310                 }
1311
1312                 # Check against page_restrictions table requirements on this
1313                 # page. The user must possess all required rights for this action.
1314                 foreach( $this->getRestrictions($action) as $right ) {
1315                         // Backwards compatibility, rewrite sysop -> protect
1316                         if( $right == 'sysop' ) {
1317                                 $right = 'protect';
1318                         }
1319                         if( '' != $right && !$user->isAllowed( $right ) ) {
1320                                 // Users with 'editprotected' permission can edit protected pages
1321                                 if( $action=='edit' && $user->isAllowed( 'editprotected' ) ) {
1322                                         // Users with 'editprotected' permission cannot edit protected pages
1323                                         // with cascading option turned on.
1324                                         if( $this->mCascadeRestriction ) {
1325                                                 $errors[] = array( 'protectedpagetext', $right );
1326                                         }
1327                                 } else {
1328                                         $errors[] = array( 'protectedpagetext', $right );
1329                                 }
1330                         }
1331                 }
1332                 # Short-circuit point
1333                 if( $short && count($errors) > 0 ) {
1334                         wfProfileOut( __METHOD__ );
1335                         return $errors;
1336                 }
1337
1338                 if( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1339                         # We /could/ use the protection level on the source page, but it's fairly ugly
1340                         #  as we have to establish a precedence hierarchy for pages included by multiple
1341                         #  cascade-protected pages. So just restrict it to people with 'protect' permission,
1342                         #  as they could remove the protection anyway.
1343                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1344                         # Cascading protection depends on more than this page...
1345                         # Several cascading protected pages may include this page...
1346                         # Check each cascading level
1347                         # This is only for protection restrictions, not for all actions
1348                         if( $cascadingSources > 0 && isset($restrictions[$action]) ) {
1349                                 foreach( $restrictions[$action] as $right ) {
1350                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1351                                         if( '' != $right && !$user->isAllowed( $right ) ) {
1352                                                 $pages = '';
1353                                                 foreach( $cascadingSources as $page )
1354                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1355                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1356                                         }
1357                                 }
1358                         }
1359                 }
1360                 # Short-circuit point
1361                 if( $short && count($errors) > 0 ) {
1362                         wfProfileOut( __METHOD__ );
1363                         return $errors;
1364                 }
1365
1366                 if( $action == 'protect' ) {
1367                         if( $this->getUserPermissionsErrors('edit', $user) != array() ) {
1368                                 $errors[] = array( 'protect-cantedit' ); // If they can't edit, they shouldn't protect.
1369                         }
1370                 }
1371
1372                 if( $action == 'create' ) {
1373                         $title_protection = $this->getTitleProtection();
1374                         if( is_array($title_protection) ) {
1375                                 extract($title_protection); // is this extract() really needed?
1376
1377                                 if( $pt_create_perm == 'sysop' ) {
1378                                         $pt_create_perm = 'protect'; // B/C
1379                                 }
1380                                 if( $pt_create_perm == '' || !$user->isAllowed($pt_create_perm) ) {
1381                                         $errors[] = array( 'titleprotected', User::whoIs($pt_user), $pt_reason );
1382                                 }
1383                         }
1384                 } elseif( $action == 'move' ) {
1385                         // Check for immobile pages
1386                         if( !MWNamespace::isMovable( $this->getNamespace() ) ) {
1387                                 // Specific message for this case
1388                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1389                         } elseif( !$this->isMovable() ) {
1390                                 // Less specific message for rarer cases
1391                                 $errors[] = array( 'immobile-page' );
1392                         }
1393                 } elseif( $action == 'move-target' ) {
1394                         if( !MWNamespace::isMovable( $this->getNamespace() ) ) {
1395                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1396                         } elseif( !$this->isMovable() ) {
1397                                 $errors[] = array( 'immobile-target-page' );
1398                         }
1399                 }
1400
1401                 wfProfileOut( __METHOD__ );
1402                 return $errors;
1403         }
1404
1405         /**
1406          * Is this title subject to title protection?
1407          * @return \type{\mixed} An associative array representing any existent title
1408          *   protection, or false if there's none.
1409          */
1410         private function getTitleProtection() {
1411                 // Can't protect pages in special namespaces
1412                 if ( $this->getNamespace() < 0 ) {
1413                         return false;
1414                 }
1415
1416                 $dbr = wfGetDB( DB_SLAVE );
1417                 $res = $dbr->select( 'protected_titles', '*',
1418                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
1419                         __METHOD__ );
1420
1421                 if ($row = $dbr->fetchRow( $res )) {
1422                         return $row;
1423                 } else {
1424                         return false;
1425                 }
1426         }
1427
1428         /**
1429          * Update the title protection status
1430          * @param $create_perm \type{\string} Permission required for creation
1431          * @param $reason \type{\string} Reason for protection
1432          * @param $expiry \type{\string} Expiry timestamp
1433          */
1434         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
1435                 global $wgUser,$wgContLang;
1436
1437                 if ($create_perm == implode(',',$this->getRestrictions('create'))
1438                         && $expiry == $this->mRestrictionsExpiry['create']) {
1439                         // No change
1440                         return true;
1441                 }
1442
1443                 list ($namespace, $title) = array( $this->getNamespace(), $this->getDBkey() );
1444
1445                 $dbw = wfGetDB( DB_MASTER );
1446
1447                 $encodedExpiry = Block::encodeExpiry($expiry, $dbw );
1448
1449                 $expiry_description = '';
1450                 if ( $encodedExpiry != 'infinity' ) {
1451                         $expiry_description = ' (' . wfMsgForContent( 'protect-expiring', $wgContLang->timeanddate( $expiry ) , $wgContLang->date( $expiry ) , $wgContLang->time( $expiry ) ).')';
1452                 }
1453                 else {
1454                         $expiry_description .= ' (' . wfMsgForContent( 'protect-expiry-indefinite' ).')';
1455                 }
1456
1457                 # Update protection table
1458                 if ($create_perm != '' ) {
1459                         $dbw->replace( 'protected_titles', array(array('pt_namespace', 'pt_title')),
1460                                 array( 'pt_namespace' => $namespace, 'pt_title' => $title
1461                                         , 'pt_create_perm' => $create_perm
1462                                         , 'pt_timestamp' => Block::encodeExpiry(wfTimestampNow(), $dbw)
1463                                         , 'pt_expiry' => $encodedExpiry
1464                                         , 'pt_user' => $wgUser->getId(), 'pt_reason' => $reason ), __METHOD__  );
1465                 } else {
1466                         $dbw->delete( 'protected_titles', array( 'pt_namespace' => $namespace,
1467                                 'pt_title' => $title ), __METHOD__ );
1468                 }
1469                 # Update the protection log
1470                 $log = new LogPage( 'protect' );
1471
1472                 if( $create_perm ) {
1473                         $params = array("[create=$create_perm] $expiry_description",'');
1474                         $log->addEntry( $this->mRestrictions['create'] ? 'modify' : 'protect', $this, trim( $reason ), $params );
1475                 } else {
1476                         $log->addEntry( 'unprotect', $this, $reason );
1477                 }
1478
1479                 return true;
1480         }
1481
1482         /**
1483          * Remove any title protection due to page existing
1484          */
1485         public function deleteTitleProtection() {
1486                 $dbw = wfGetDB( DB_MASTER );
1487
1488                 $dbw->delete( 'protected_titles',
1489                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
1490                         __METHOD__ );
1491         }
1492
1493         /**
1494          * Can $wgUser edit this page?
1495          * @return \type{\bool} TRUE or FALSE
1496          * @deprecated use userCan('edit')
1497          */
1498         public function userCanEdit( $doExpensiveQueries = true ) {
1499                 return $this->userCan( 'edit', $doExpensiveQueries );
1500         }
1501
1502         /**
1503          * Can $wgUser create this page?
1504          * @return \type{\bool} TRUE or FALSE
1505          * @deprecated use userCan('create')
1506          */
1507         public function userCanCreate( $doExpensiveQueries = true ) {
1508                 return $this->userCan( 'create', $doExpensiveQueries );
1509         }
1510
1511         /**
1512          * Can $wgUser move this page?
1513          * @return \type{\bool} TRUE or FALSE
1514          * @deprecated use userCan('move')
1515          */
1516         public function userCanMove( $doExpensiveQueries = true ) {
1517                 return $this->userCan( 'move', $doExpensiveQueries );
1518         }
1519
1520         /**
1521          * Would anybody with sufficient privileges be able to move this page?
1522          * Some pages just aren't movable.
1523          *
1524          * @return \type{\bool} TRUE or FALSE
1525          */
1526         public function isMovable() {
1527                 return MWNamespace::isMovable( $this->getNamespace() ) && $this->getInterwiki() == '';
1528         }
1529
1530         /**
1531          * Can $wgUser read this page?
1532          * @return \type{\bool} TRUE or FALSE
1533          * @todo fold these checks into userCan()
1534          */
1535         public function userCanRead() {
1536                 global $wgUser, $wgGroupPermissions;
1537
1538                 $result = null;
1539                 wfRunHooks( 'userCan', array( &$this, &$wgUser, 'read', &$result ) );
1540                 if ( $result !== null ) {
1541                         return $result;
1542                 }
1543
1544                 # Shortcut for public wikis, allows skipping quite a bit of code
1545                 if ( !empty( $wgGroupPermissions['*']['read'] ) )
1546                         return true;
1547
1548                 if( $wgUser->isAllowed( 'read' ) ) {
1549                         return true;
1550                 } else {
1551                         global $wgWhitelistRead;
1552
1553                         /**
1554                          * Always grant access to the login page.
1555                          * Even anons need to be able to log in.
1556                         */
1557                         if( $this->isSpecial( 'Userlogin' ) || $this->isSpecial( 'Resetpass' ) ) {
1558                                 return true;
1559                         }
1560
1561                         /**
1562                          * Bail out if there isn't whitelist
1563                          */
1564                         if( !is_array($wgWhitelistRead) ) {
1565                                 return false;
1566                         }
1567
1568                         /**
1569                          * Check for explicit whitelisting
1570                          */
1571                         $name = $this->getPrefixedText();
1572                         $dbName = $this->getPrefixedDBKey();
1573                         // Check with and without underscores
1574                         if( in_array($name,$wgWhitelistRead,true) || in_array($dbName,$wgWhitelistRead,true) )
1575                                 return true;
1576
1577                         /**
1578                          * Old settings might have the title prefixed with
1579                          * a colon for main-namespace pages
1580                          */
1581                         if( $this->getNamespace() == NS_MAIN ) {
1582                                 if( in_array( ':' . $name, $wgWhitelistRead ) )
1583                                         return true;
1584                         }
1585
1586                         /**
1587                          * If it's a special page, ditch the subpage bit
1588                          * and check again
1589                          */
1590                         if( $this->getNamespace() == NS_SPECIAL ) {
1591                                 $name = $this->getDBkey();
1592                                 list( $name, /* $subpage */) = SpecialPage::resolveAliasWithSubpage( $name );
1593                                 if ( $name === false ) {
1594                                         # Invalid special page, but we show standard login required message
1595                                         return false;
1596                                 }
1597
1598                                 $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
1599                                 if( in_array( $pure, $wgWhitelistRead, true ) )
1600                                         return true;
1601                         }
1602
1603                 }
1604                 return false;
1605         }
1606
1607         /**
1608          * Is this a talk page of some sort?
1609          * @return \type{\bool} TRUE or FALSE
1610          */
1611         public function isTalkPage() {
1612                 return MWNamespace::isTalk( $this->getNamespace() );
1613         }
1614
1615         /**
1616          * Is this a subpage?
1617          * @return \type{\bool} TRUE or FALSE
1618          */
1619         public function isSubpage() {
1620                 return MWNamespace::hasSubpages( $this->mNamespace )
1621                         ? strpos( $this->getText(), '/' ) !== false
1622                         : false;
1623         }
1624
1625         /**
1626          * Does this have subpages?  (Warning, usually requires an extra DB query.)
1627          * @return \type{\bool} TRUE or FALSE
1628          */
1629         public function hasSubpages() {
1630                 if( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1631                         # Duh
1632                         return false;
1633                 }
1634
1635                 # We dynamically add a member variable for the purpose of this method
1636                 # alone to cache the result.  There's no point in having it hanging
1637                 # around uninitialized in every Title object; therefore we only add it
1638                 # if needed and don't declare it statically.
1639                 if( isset( $this->mHasSubpages ) ) {
1640                         return $this->mHasSubpages;
1641                 }
1642
1643                 $db = wfGetDB( DB_SLAVE );
1644                 $subpages = $this->getSubpages( 1 );
1645                 if( $subpages instanceof TitleArray )
1646                         return $this->mHasSubpages = (bool)$subpages->count();
1647                 return $this->mHasSubpages = false;
1648         }
1649
1650         /**
1651          * Get all subpages of this page.
1652          * @param $limit Maximum number of subpages to fetch; -1 for no limit
1653          * @return mixed TitleArray, or empty array if this page's namespace
1654          *  doesn't allow subpages
1655          */
1656         public function getSubpages($limit = -1) {
1657                 if( !MWNamespace::hasSubpages( $this->getNamespace() ) )
1658                         return array();
1659
1660                 $dbr = wfGetDB( DB_SLAVE );
1661                 $conds['page_namespace'] = $this->getNamespace();
1662                 $conds[] = 'page_title LIKE ' . $dbr->addQuotes(
1663                                 $dbr->escapeLike( $this->getDBkey() ) . '/%' );
1664                 $options = array();
1665                 if( $limit > -1 )
1666                         $options['LIMIT'] = $limit;
1667                 return $this->mSubpages = TitleArray::newFromResult(
1668                         $dbr->select( 'page',
1669                                 array( 'page_id', 'page_namespace', 'page_title' ),
1670                                 $conds,
1671                                 __METHOD__,
1672                                 $options
1673                         )
1674                 );
1675         }
1676
1677         /**
1678          * Could this page contain custom CSS or JavaScript, based
1679          * on the title?
1680          *
1681          * @return \type{\bool} TRUE or FALSE
1682          */
1683         public function isCssOrJsPage() {
1684                 return $this->mNamespace == NS_MEDIAWIKI
1685                         && preg_match( '!\.(?:css|js)$!u', $this->mTextform ) > 0;
1686         }
1687
1688         /**
1689          * Is this a .css or .js subpage of a user page?
1690          * @return \type{\bool} TRUE or FALSE
1691          */
1692         public function isCssJsSubpage() {
1693                 return ( NS_USER == $this->mNamespace and preg_match("/\\/.*\\.(?:css|js)$/", $this->mTextform ) );
1694         }
1695         /**
1696          * Is this a *valid* .css or .js subpage of a user page?
1697          * Check that the corresponding skin exists
1698          * @return \type{\bool} TRUE or FALSE
1699          */
1700         public function isValidCssJsSubpage() {
1701                 if ( $this->isCssJsSubpage() ) {
1702                         $skinNames = Skin::getSkinNames();
1703                         return array_key_exists( $this->getSkinFromCssJsSubpage(), $skinNames );
1704                 } else {
1705                         return false;
1706                 }
1707         }
1708         /**
1709          * Trim down a .css or .js subpage title to get the corresponding skin name
1710          */
1711         public function getSkinFromCssJsSubpage() {
1712                 $subpage = explode( '/', $this->mTextform );
1713                 $subpage = $subpage[ count( $subpage ) - 1 ];
1714                 return( str_replace( array( '.css', '.js' ), array( '', '' ), $subpage ) );
1715         }
1716         /**
1717          * Is this a .css subpage of a user page?
1718          * @return \type{\bool} TRUE or FALSE
1719          */
1720         public function isCssSubpage() {
1721                 return ( NS_USER == $this->mNamespace && preg_match("/\\/.*\\.css$/", $this->mTextform ) );
1722         }
1723         /**
1724          * Is this a .js subpage of a user page?
1725          * @return \type{\bool} TRUE or FALSE
1726          */
1727         public function isJsSubpage() {
1728                 return ( NS_USER == $this->mNamespace && preg_match("/\\/.*\\.js$/", $this->mTextform ) );
1729         }
1730         /**
1731          * Protect css/js subpages of user pages: can $wgUser edit
1732          * this page?
1733          *
1734          * @return \type{\bool} TRUE or FALSE
1735          * @todo XXX: this might be better using restrictions
1736          */
1737         public function userCanEditCssJsSubpage() {
1738                 global $wgUser;
1739                 return ( $wgUser->isAllowed('editusercssjs') || preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1740         }
1741
1742         /**
1743          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
1744          *
1745          * @return \type{\bool} If the page is subject to cascading restrictions.
1746          */
1747         public function isCascadeProtected() {
1748                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
1749                 return ( $sources > 0 );
1750         }
1751
1752         /**
1753          * Cascading protection: Get the source of any cascading restrictions on this page.
1754          *
1755          * @param $get_pages \type{\bool} Whether or not to retrieve the actual pages that the restrictions have come from.
1756          * @return \type{\arrayof{mixed title array, restriction array}} Array of the Title objects of the pages from
1757          *         which cascading restrictions have come, false for none, or true if such restrictions exist, but $get_pages was not set.
1758          *         The restriction array is an array of each type, each of which contains an array of unique groups.
1759          */
1760         public function getCascadeProtectionSources( $get_pages = true ) {
1761                 global $wgRestrictionTypes;
1762
1763                 # Define our dimension of restrictions types
1764                 $pagerestrictions = array();
1765                 foreach( $wgRestrictionTypes as $action )
1766                         $pagerestrictions[$action] = array();
1767
1768                 if ( isset( $this->mCascadeSources ) && $get_pages ) {
1769                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
1770                 } else if ( isset( $this->mHasCascadingRestrictions ) && !$get_pages ) {
1771                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
1772                 }
1773
1774                 wfProfileIn( __METHOD__ );
1775
1776                 $dbr = wfGetDB( DB_SLAVE );
1777
1778                 if ( $this->getNamespace() == NS_FILE ) {
1779                         $tables = array ('imagelinks', 'page_restrictions');
1780                         $where_clauses = array(
1781                                 'il_to' => $this->getDBkey(),
1782                                 'il_from=pr_page',
1783                                 'pr_cascade' => 1 );
1784                 } else {
1785                         $tables = array ('templatelinks', 'page_restrictions');
1786                         $where_clauses = array(
1787                                 'tl_namespace' => $this->getNamespace(),
1788                                 'tl_title' => $this->getDBkey(),
1789                                 'tl_from=pr_page',
1790                                 'pr_cascade' => 1 );
1791                 }
1792
1793                 if ( $get_pages ) {
1794                         $cols = array('pr_page', 'page_namespace', 'page_title', 'pr_expiry', 'pr_type', 'pr_level' );
1795                         $where_clauses[] = 'page_id=pr_page';
1796                         $tables[] = 'page';
1797                 } else {
1798                         $cols = array( 'pr_expiry' );
1799                 }
1800
1801                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
1802
1803                 $sources = $get_pages ? array() : false;
1804                 $now = wfTimestampNow();
1805                 $purgeExpired = false;
1806
1807                 foreach( $res as $row ) {
1808                         $expiry = Block::decodeExpiry( $row->pr_expiry );
1809                         if( $expiry > $now ) {
1810                                 if ($get_pages) {
1811                                         $page_id = $row->pr_page;
1812                                         $page_ns = $row->page_namespace;
1813                                         $page_title = $row->page_title;
1814                                         $sources[$page_id] = Title::makeTitle($page_ns, $page_title);
1815                                         # Add groups needed for each restriction type if its not already there
1816                                         # Make sure this restriction type still exists
1817                                         if ( isset($pagerestrictions[$row->pr_type]) && !in_array($row->pr_level, $pagerestrictions[$row->pr_type]) ) {
1818                                                 $pagerestrictions[$row->pr_type][]=$row->pr_level;
1819                                         }
1820                                 } else {
1821                                         $sources = true;
1822                                 }
1823                         } else {
1824                                 // Trigger lazy purge of expired restrictions from the db
1825                                 $purgeExpired = true;
1826                         }
1827                 }
1828                 if( $purgeExpired ) {
1829                         Title::purgeExpiredRestrictions();
1830                 }
1831
1832                 wfProfileOut( __METHOD__ );
1833
1834                 if ( $get_pages ) {
1835                         $this->mCascadeSources = $sources;
1836                         $this->mCascadingRestrictions = $pagerestrictions;
1837                 } else {
1838                         $this->mHasCascadingRestrictions = $sources;
1839                 }
1840                 return array( $sources, $pagerestrictions );
1841         }
1842
1843         function areRestrictionsCascading() {
1844                 if (!$this->mRestrictionsLoaded) {
1845                         $this->loadRestrictions();
1846                 }
1847
1848                 return $this->mCascadeRestriction;
1849         }
1850
1851         /**
1852          * Loads a string into mRestrictions array
1853          * @param $res \type{Resource} restrictions as an SQL result.
1854          */
1855         private function loadRestrictionsFromRow( $res, $oldFashionedRestrictions = NULL ) {
1856                 global $wgRestrictionTypes;
1857                 $dbr = wfGetDB( DB_SLAVE );
1858
1859                 foreach( $wgRestrictionTypes as $type ){
1860                         $this->mRestrictions[$type] = array();
1861                         $this->mRestrictionsExpiry[$type] = Block::decodeExpiry('');
1862                 }
1863
1864                 $this->mCascadeRestriction = false;
1865
1866                 # Backwards-compatibility: also load the restrictions from the page record (old format).
1867
1868                 if ( $oldFashionedRestrictions === NULL ) {
1869                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
1870                                 array( 'page_id' => $this->getArticleId() ), __METHOD__ );
1871                 }
1872
1873                 if ($oldFashionedRestrictions != '') {
1874
1875                         foreach( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
1876                                 $temp = explode( '=', trim( $restrict ) );
1877                                 if(count($temp) == 1) {
1878                                         // old old format should be treated as edit/move restriction
1879                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
1880                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
1881                                 } else {
1882                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
1883                                 }
1884                         }
1885
1886                         $this->mOldRestrictions = true;
1887
1888                 }
1889
1890                 if( $dbr->numRows( $res ) ) {
1891                         # Current system - load second to make them override.
1892                         $now = wfTimestampNow();
1893                         $purgeExpired = false;
1894
1895                         foreach( $res as $row ) {
1896                                 # Cycle through all the restrictions.
1897
1898                                 // Don't take care of restrictions types that aren't in $wgRestrictionTypes
1899                                 if( !in_array( $row->pr_type, $wgRestrictionTypes ) )
1900                                         continue;
1901
1902                                 // This code should be refactored, now that it's being used more generally,
1903                                 // But I don't really see any harm in leaving it in Block for now -werdna
1904                                 $expiry = Block::decodeExpiry( $row->pr_expiry );
1905
1906                                 // Only apply the restrictions if they haven't expired!
1907                                 if ( !$expiry || $expiry > $now ) {
1908                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
1909                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
1910
1911                                         $this->mCascadeRestriction |= $row->pr_cascade;
1912                                 } else {
1913                                         // Trigger a lazy purge of expired restrictions
1914                                         $purgeExpired = true;
1915                                 }
1916                         }
1917
1918                         if( $purgeExpired ) {
1919                                 Title::purgeExpiredRestrictions();
1920                         }
1921                 }
1922
1923                 $this->mRestrictionsLoaded = true;
1924         }
1925
1926         /**
1927          * Load restrictions from the page_restrictions table
1928          */
1929         public function loadRestrictions( $oldFashionedRestrictions = NULL ) {
1930                 if( !$this->mRestrictionsLoaded ) {
1931                         if ($this->exists()) {
1932                                 $dbr = wfGetDB( DB_SLAVE );
1933
1934                                 $res = $dbr->select( 'page_restrictions', '*',
1935                                         array ( 'pr_page' => $this->getArticleId() ), __METHOD__ );
1936
1937                                 $this->loadRestrictionsFromRow( $res, $oldFashionedRestrictions );
1938                         } else {
1939                                 $title_protection = $this->getTitleProtection();
1940
1941                                 if (is_array($title_protection)) {
1942                                         extract($title_protection);
1943
1944                                         $now = wfTimestampNow();
1945                                         $expiry = Block::decodeExpiry($pt_expiry);
1946
1947                                         if (!$expiry || $expiry > $now) {
1948                                                 // Apply the restrictions
1949                                                 $this->mRestrictionsExpiry['create'] = $expiry;
1950                                                 $this->mRestrictions['create'] = explode(',', trim($pt_create_perm) );
1951                                         } else { // Get rid of the old restrictions
1952                                                 Title::purgeExpiredRestrictions();
1953                                         }
1954                                 } else {
1955                                         $this->mRestrictionsExpiry['create'] = Block::decodeExpiry('');
1956                                 }
1957                                 $this->mRestrictionsLoaded = true;
1958                         }
1959                 }
1960         }
1961
1962         /**
1963          * Purge expired restrictions from the page_restrictions table
1964          */
1965         static function purgeExpiredRestrictions() {
1966                 $dbw = wfGetDB( DB_MASTER );
1967                 $dbw->delete( 'page_restrictions',
1968                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
1969                         __METHOD__ );
1970
1971                 $dbw->delete( 'protected_titles',
1972                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
1973                         __METHOD__ );
1974         }
1975
1976         /**
1977          * Accessor/initialisation for mRestrictions
1978          *
1979          * @param $action \type{\string} action that permission needs to be checked for
1980          * @return \type{\arrayof{\string}} the array of groups allowed to edit this article
1981          */
1982         public function getRestrictions( $action ) {
1983                 if( !$this->mRestrictionsLoaded ) {
1984                         $this->loadRestrictions();
1985                 }
1986                 return isset( $this->mRestrictions[$action] )
1987                                 ? $this->mRestrictions[$action]
1988                                 : array();
1989         }
1990
1991         /**
1992          * Get the expiry time for the restriction against a given action
1993          * @return 14-char timestamp, or 'infinity' if the page is protected forever
1994          * or not protected at all, or false if the action is not recognised.
1995          */
1996         public function getRestrictionExpiry( $action ) {
1997                 if( !$this->mRestrictionsLoaded ) {
1998                         $this->loadRestrictions();
1999                 }
2000                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2001         }
2002
2003         /**
2004          * Is there a version of this page in the deletion archive?
2005          * @return \type{\int} the number of archived revisions
2006          */
2007         public function isDeleted() {
2008                 $fname = 'Title::isDeleted';
2009                 if ( $this->getNamespace() < 0 ) {
2010                         $n = 0;
2011                 } else {
2012                         $dbr = wfGetDB( DB_SLAVE );
2013                         $n = $dbr->selectField( 'archive', 'COUNT(*)', array( 'ar_namespace' => $this->getNamespace(),
2014                                 'ar_title' => $this->getDBkey() ), $fname );
2015                         if( $this->getNamespace() == NS_FILE ) {
2016                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2017                                         array( 'fa_name' => $this->getDBkey() ), $fname );
2018                         }
2019                 }
2020                 return (int)$n;
2021         }
2022
2023         /**
2024          * Get the article ID for this Title from the link cache,
2025          * adding it if necessary
2026          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select
2027          *      for update
2028          * @return \type{\int} the ID
2029          */
2030         public function getArticleID( $flags = 0 ) {
2031                 if( $this->getNamespace() < 0 ) {
2032                         return $this->mArticleID = 0;
2033                 }
2034                 $linkCache = LinkCache::singleton();
2035                 if( $flags & GAID_FOR_UPDATE ) {
2036                         $oldUpdate = $linkCache->forUpdate( true );
2037                         $linkCache->clearLink( $this );
2038                         $this->mArticleID = $linkCache->addLinkObj( $this );
2039                         $linkCache->forUpdate( $oldUpdate );
2040                 } else {
2041                         if( -1 == $this->mArticleID ) {
2042                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2043                         }
2044                 }
2045                 return $this->mArticleID;
2046         }
2047
2048         /**
2049          * Is this an article that is a redirect page?
2050          * Uses link cache, adding it if necessary
2051          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select for update
2052          * @return \type{\bool}
2053          */
2054         public function isRedirect( $flags = 0 ) {
2055                 if( !is_null($this->mRedirect) )
2056                         return $this->mRedirect;
2057                 # Calling getArticleID() loads the field from cache as needed
2058                 if( !$this->getArticleID($flags) ) {
2059                         return $this->mRedirect = false;
2060                 }
2061                 $linkCache = LinkCache::singleton();
2062                 $this->mRedirect = (bool)$linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2063
2064                 return $this->mRedirect;
2065         }
2066
2067         /**
2068          * What is the length of this page?
2069          * Uses link cache, adding it if necessary
2070          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select for update
2071          * @return \type{\bool}
2072          */
2073         public function getLength( $flags = 0 ) {
2074                 if( $this->mLength != -1 )
2075                         return $this->mLength;
2076                 # Calling getArticleID() loads the field from cache as needed
2077                 if( !$this->getArticleID($flags) ) {
2078                         return $this->mLength = 0;
2079                 }
2080                 $linkCache = LinkCache::singleton();
2081                 $this->mLength = intval( $linkCache->getGoodLinkFieldObj( $this, 'length' ) );
2082
2083                 return $this->mLength;
2084         }
2085
2086         /**
2087          * What is the page_latest field for this page?
2088          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select for update
2089          * @return \type{\int}
2090          */
2091         public function getLatestRevID( $flags = 0 ) {
2092                 if( $this->mLatestID !== false )
2093                         return $this->mLatestID;
2094
2095                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB(DB_MASTER) : wfGetDB(DB_SLAVE);
2096                 $this->mLatestID = $db->selectField( 'page', 'page_latest', $this->pageCond(), __METHOD__ );
2097                 return $this->mLatestID;
2098         }
2099
2100         /**
2101          * This clears some fields in this object, and clears any associated
2102          * keys in the "bad links" section of the link cache.
2103          *
2104          * - This is called from Article::insertNewArticle() to allow
2105          * loading of the new page_id. It's also called from
2106          * Article::doDeleteArticle()
2107          *
2108          * @param $newid \type{\int} the new Article ID
2109          */
2110         public function resetArticleID( $newid ) {
2111                 $linkCache = LinkCache::singleton();
2112                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
2113
2114                 if ( 0 == $newid ) { $this->mArticleID = -1; }
2115                 else { $this->mArticleID = $newid; }
2116                 $this->mRestrictionsLoaded = false;
2117                 $this->mRestrictions = array();
2118         }
2119
2120         /**
2121          * Updates page_touched for this page; called from LinksUpdate.php
2122          * @return \type{\bool} true if the update succeded
2123          */
2124         public function invalidateCache() {
2125                 if( wfReadOnly() ) {
2126                         return;
2127                 }
2128                 $dbw = wfGetDB( DB_MASTER );
2129                 $success = $dbw->update( 'page',
2130                         array( 'page_touched' => $dbw->timestamp() ),
2131                         $this->pageCond(),
2132                         __METHOD__
2133                 );
2134                 HTMLFileCache::clearFileCache( $this );
2135                 return $success;
2136         }
2137
2138         /**
2139          * Prefix some arbitrary text with the namespace or interwiki prefix
2140          * of this object
2141          *
2142          * @param $name \type{\string} the text
2143          * @return \type{\string} the prefixed text
2144          * @private
2145          */
2146         /* private */ function prefix( $name ) {
2147                 $p = '';
2148                 if ( '' != $this->mInterwiki ) {
2149                         $p = $this->mInterwiki . ':';
2150                 }
2151                 if ( 0 != $this->mNamespace ) {
2152                         $p .= $this->getNsText() . ':';
2153                 }
2154                 return $p . $name;
2155         }
2156
2157         /**
2158          * Secure and split - main initialisation function for this object
2159          *
2160          * Assumes that mDbkeyform has been set, and is urldecoded
2161          * and uses underscores, but not otherwise munged.  This function
2162          * removes illegal characters, splits off the interwiki and
2163          * namespace prefixes, sets the other forms, and canonicalizes
2164          * everything.
2165          * @return \type{\bool} true on success
2166          */
2167         private function secureAndSplit() {
2168                 global $wgContLang, $wgLocalInterwiki, $wgCapitalLinks;
2169
2170                 # Initialisation
2171                 static $rxTc = false;
2172                 if( !$rxTc ) {
2173                         # Matching titles will be held as illegal.
2174                         $rxTc = '/' .
2175                                 # Any character not allowed is forbidden...
2176                                 '[^' . Title::legalChars() . ']' .
2177                                 # URL percent encoding sequences interfere with the ability
2178                                 # to round-trip titles -- you can't link to them consistently.
2179                                 '|%[0-9A-Fa-f]{2}' .
2180                                 # XML/HTML character references produce similar issues.
2181                                 '|&[A-Za-z0-9\x80-\xff]+;' .
2182                                 '|&#[0-9]+;' .
2183                                 '|&#x[0-9A-Fa-f]+;' .
2184                                 '/S';
2185                 }
2186
2187                 $this->mInterwiki = $this->mFragment = '';
2188                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2189
2190                 $dbkey = $this->mDbkeyform;
2191
2192                 # Strip Unicode bidi override characters.
2193                 # Sometimes they slip into cut-n-pasted page titles, where the
2194                 # override chars get included in list displays.
2195                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
2196
2197                 # Clean up whitespace
2198                 #
2199                 $dbkey = preg_replace( '/[ _]+/', '_', $dbkey );
2200                 $dbkey = trim( $dbkey, '_' );
2201
2202                 if ( '' == $dbkey ) {
2203                         return false;
2204                 }
2205
2206                 if( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2207                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2208                         return false;
2209                 }
2210
2211                 $this->mDbkeyform = $dbkey;
2212
2213                 # Initial colon indicates main namespace rather than specified default
2214                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
2215                 if ( ':' == $dbkey{0} ) {
2216                         $this->mNamespace = NS_MAIN;
2217                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
2218                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
2219                 }
2220
2221                 # Namespace or interwiki prefix
2222                 $firstPass = true;
2223                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
2224                 do {
2225                         $m = array();
2226                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
2227                                 $p = $m[1];
2228                                 if ( $ns = $wgContLang->getNsIndex( $p ) ) {
2229                                         # Ordinary namespace
2230                                         $dbkey = $m[2];
2231                                         $this->mNamespace = $ns;
2232                                         # For Talk:X pages, check if X has a "namespace" prefix
2233                                         if( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
2234                                                 if( $wgContLang->getNsIndex( $x[1] ) )
2235                                                         return false; # Disallow Talk:File:x type titles...
2236                                                 else if( Interwiki::isValidInterwiki( $x[1] ) )
2237                                                         return false; # Disallow Talk:Interwiki:x type titles...
2238                                         }
2239                                 } elseif( Interwiki::isValidInterwiki( $p ) ) {
2240                                         if( !$firstPass ) {
2241                                                 # Can't make a local interwiki link to an interwiki link.
2242                                                 # That's just crazy!
2243                                                 return false;
2244                                         }
2245
2246                                         # Interwiki link
2247                                         $dbkey = $m[2];
2248                                         $this->mInterwiki = $wgContLang->lc( $p );
2249
2250                                         # Redundant interwiki prefix to the local wiki
2251                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
2252                                                 if( $dbkey == '' ) {
2253                                                         # Can't have an empty self-link
2254                                                         return false;
2255                                                 }
2256                                                 $this->mInterwiki = '';
2257                                                 $firstPass = false;
2258                                                 # Do another namespace split...
2259                                                 continue;
2260                                         }
2261
2262                                         # If there's an initial colon after the interwiki, that also
2263                                         # resets the default namespace
2264                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
2265                                                 $this->mNamespace = NS_MAIN;
2266                                                 $dbkey = substr( $dbkey, 1 );
2267                                         }
2268                                 }
2269                                 # If there's no recognized interwiki or namespace,
2270                                 # then let the colon expression be part of the title.
2271                         }
2272                         break;
2273                 } while( true );
2274
2275                 # We already know that some pages won't be in the database!
2276                 #
2277                 if ( '' != $this->mInterwiki || NS_SPECIAL == $this->mNamespace ) {
2278                         $this->mArticleID = 0;
2279                 }
2280                 $fragment = strstr( $dbkey, '#' );
2281                 if ( false !== $fragment ) {
2282                         $this->setFragment( $fragment );
2283                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
2284                         # remove whitespace again: prevents "Foo_bar_#"
2285                         # becoming "Foo_bar_"
2286                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
2287                 }
2288
2289                 # Reject illegal characters.
2290                 #
2291                 if( preg_match( $rxTc, $dbkey ) ) {
2292                         return false;
2293                 }
2294
2295                 /**
2296                  * Pages with "/./" or "/../" appearing in the URLs will often be un-
2297                  * reachable due to the way web browsers deal with 'relative' URLs.
2298                  * Also, they conflict with subpage syntax.  Forbid them explicitly.
2299                  */
2300                 if ( strpos( $dbkey, '.' ) !== false &&
2301                      ( $dbkey === '.' || $dbkey === '..' ||
2302                        strpos( $dbkey, './' ) === 0  ||
2303                        strpos( $dbkey, '../' ) === 0 ||
2304                        strpos( $dbkey, '/./' ) !== false ||
2305                        strpos( $dbkey, '/../' ) !== false  ||
2306                        substr( $dbkey, -2 ) == '/.' ||
2307                        substr( $dbkey, -3 ) == '/..' ) )
2308                 {
2309                         return false;
2310                 }
2311
2312                 /**
2313                  * Magic tilde sequences? Nu-uh!
2314                  */
2315                 if( strpos( $dbkey, '~~~' ) !== false ) {
2316                         return false;
2317                 }
2318
2319                 /**
2320                  * Limit the size of titles to 255 bytes.
2321                  * This is typically the size of the underlying database field.
2322                  * We make an exception for special pages, which don't need to be stored
2323                  * in the database, and may edge over 255 bytes due to subpage syntax
2324                  * for long titles, e.g. [[Special:Block/Long name]]
2325                  */
2326                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
2327                   strlen( $dbkey ) > 512 )
2328                 {
2329                         return false;
2330                 }
2331
2332                 /**
2333                  * Normally, all wiki links are forced to have
2334                  * an initial capital letter so [[foo]] and [[Foo]]
2335                  * point to the same place.
2336                  *
2337                  * Don't force it for interwikis, since the other
2338                  * site might be case-sensitive.
2339                  */
2340                 $this->mUserCaseDBKey = $dbkey;
2341                 if( $wgCapitalLinks && $this->mInterwiki == '') {
2342                         $dbkey = $wgContLang->ucfirst( $dbkey );
2343                 }
2344
2345                 /**
2346                  * Can't make a link to a namespace alone...
2347                  * "empty" local links can only be self-links
2348                  * with a fragment identifier.
2349                  */
2350                 if( $dbkey == '' &&
2351                         $this->mInterwiki == '' &&
2352                         $this->mNamespace != NS_MAIN ) {
2353                         return false;
2354                 }
2355                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
2356                 // IP names are not allowed for accounts, and can only be referring to
2357                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
2358                 // there are numerous ways to present the same IP. Having sp:contribs scan
2359                 // them all is silly and having some show the edits and others not is
2360                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
2361                 $dbkey = ($this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK) ?
2362                         IP::sanitizeIP( $dbkey ) : $dbkey;
2363                 // Any remaining initial :s are illegal.
2364                 if ( $dbkey !== '' && ':' == $dbkey{0} ) {
2365                         return false;
2366                 }
2367
2368                 # Fill fields
2369                 $this->mDbkeyform = $dbkey;
2370                 $this->mUrlform = wfUrlencode( $dbkey );
2371
2372                 $this->mTextform = str_replace( '_', ' ', $dbkey );
2373
2374                 return true;
2375         }
2376
2377         /**
2378          * Set the fragment for this title. Removes the first character from the
2379          * specified fragment before setting, so it assumes you're passing it with
2380          * an initial "#".
2381          *
2382          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
2383          * Still in active use privately.
2384          *
2385          * @param $fragment \type{\string} text
2386          */
2387         public function setFragment( $fragment ) {
2388                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
2389         }
2390
2391         /**
2392          * Get a Title object associated with the talk page of this article
2393          * @return \type{Title} the object for the talk page
2394          */
2395         public function getTalkPage() {
2396                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
2397         }
2398
2399         /**
2400          * Get a title object associated with the subject page of this
2401          * talk page
2402          *
2403          * @return \type{Title} the object for the subject page
2404          */
2405         public function getSubjectPage() {
2406                 // Is this the same title?
2407                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
2408                 if( $this->getNamespace() == $subjectNS ) {
2409                         return $this;
2410                 }
2411                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
2412         }
2413
2414         /**
2415          * Get an array of Title objects linking to this Title
2416          * Also stores the IDs in the link cache.
2417          *
2418          * WARNING: do not use this function on arbitrary user-supplied titles!
2419          * On heavily-used templates it will max out the memory.
2420          *
2421          * @param array $options may be FOR UPDATE
2422          * @return \type{\arrayof{Title}} the Title objects linking here
2423          */
2424         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
2425                 $linkCache = LinkCache::singleton();
2426
2427                 if ( count( $options ) > 0 ) {
2428                         $db = wfGetDB( DB_MASTER );
2429                 } else {
2430                         $db = wfGetDB( DB_SLAVE );
2431                 }
2432
2433                 $res = $db->select( array( 'page', $table ),
2434                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect' ),
2435                         array(
2436                                 "{$prefix}_from=page_id",
2437                                 "{$prefix}_namespace" => $this->getNamespace(),
2438                                 "{$prefix}_title"     => $this->getDBkey() ),
2439                         __METHOD__,
2440                         $options );
2441
2442                 $retVal = array();
2443                 if ( $db->numRows( $res ) ) {
2444                         foreach( $res as $row ) {
2445                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
2446                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj, $row->page_len, $row->page_is_redirect );
2447                                         $retVal[] = $titleObj;
2448                                 }
2449                         }
2450                 }
2451                 $db->freeResult( $res );
2452                 return $retVal;
2453         }
2454
2455         /**
2456          * Get an array of Title objects using this Title as a template
2457          * Also stores the IDs in the link cache.
2458          *
2459          * WARNING: do not use this function on arbitrary user-supplied titles!
2460          * On heavily-used templates it will max out the memory.
2461          *
2462          * @param array $options may be FOR UPDATE
2463          * @return \type{\arrayof{Title}} the Title objects linking here
2464          */
2465         public function getTemplateLinksTo( $options = array() ) {
2466                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
2467         }
2468
2469         /**
2470          * Get an array of Title objects referring to non-existent articles linked from this page
2471          *
2472          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
2473          * @param array $options may be FOR UPDATE
2474          * @return \type{\arrayof{Title}} the Title objects
2475          */
2476         public function getBrokenLinksFrom( $options = array() ) {
2477                 if ( $this->getArticleId() == 0 ) {
2478                         # All links from article ID 0 are false positives
2479                         return array();
2480                 }
2481
2482                 if ( count( $options ) > 0 ) {
2483                         $db = wfGetDB( DB_MASTER );
2484                 } else {
2485                         $db = wfGetDB( DB_SLAVE );
2486                 }
2487
2488                 $res = $db->safeQuery(
2489                           "SELECT pl_namespace, pl_title
2490                              FROM !
2491                         LEFT JOIN !
2492                                ON pl_namespace=page_namespace
2493                               AND pl_title=page_title
2494                             WHERE pl_from=?
2495                               AND page_namespace IS NULL
2496                                   !",
2497                         $db->tableName( 'pagelinks' ),
2498                         $db->tableName( 'page' ),
2499                         $this->getArticleId(),
2500                         $options );
2501
2502                 $retVal = array();
2503                 if ( $db->numRows( $res ) ) {
2504                         foreach( $res as $row ) {
2505                                 $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
2506                         }
2507                 }
2508                 $db->freeResult( $res );
2509                 return $retVal;
2510         }
2511
2512
2513         /**
2514          * Get a list of URLs to purge from the Squid cache when this
2515          * page changes
2516          *
2517          * @return \type{\arrayof{\string}} the URLs
2518          */
2519         public function getSquidURLs() {
2520                 global $wgContLang;
2521
2522                 $urls = array(
2523                         $this->getInternalURL(),
2524                         $this->getInternalURL( 'action=history' )
2525                 );
2526
2527                 // purge variant urls as well
2528                 if($wgContLang->hasVariants()){
2529                         $variants = $wgContLang->getVariants();
2530                         foreach($variants as $vCode){
2531                                 if($vCode==$wgContLang->getCode()) continue; // we don't want default variant
2532                                 $urls[] = $this->getInternalURL('',$vCode);
2533                         }
2534                 }
2535
2536                 return $urls;
2537         }
2538
2539         /**
2540          * Purge all applicable Squid URLs
2541          */
2542         public function purgeSquid() {
2543                 global $wgUseSquid;
2544                 if ( $wgUseSquid ) {
2545                         $urls = $this->getSquidURLs();
2546                         $u = new SquidUpdate( $urls );
2547                         $u->doUpdate();
2548                 }
2549         }
2550
2551         /**
2552          * Move this page without authentication
2553          * @param &$nt \type{Title} the new page Title
2554          */
2555         public function moveNoAuth( &$nt ) {
2556                 return $this->moveTo( $nt, false );
2557         }
2558
2559         /**
2560          * Check whether a given move operation would be valid.
2561          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
2562          * @param &$nt \type{Title} the new title
2563          * @param $auth \type{\bool} indicates whether $wgUser's permissions
2564          *      should be checked
2565          * @param $reason \type{\string} is the log summary of the move, used for spam checking
2566          * @return \type{\mixed} True on success, getUserPermissionsErrors()-like array on failure
2567          */
2568         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
2569                 global $wgUser;
2570
2571                 $errors = array();
2572                 if( !$nt ) {
2573                         // Normally we'd add this to $errors, but we'll get
2574                         // lots of syntax errors if $nt is not an object
2575                         return array(array('badtitletext'));
2576                 }
2577                 if( $this->equals( $nt ) ) {
2578                         $errors[] = array('selfmove');
2579                 }
2580                 if( !$this->isMovable() ) {
2581                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
2582                 }
2583                 if ( $nt->getInterwiki() != '' ) {
2584                         $errors[] = array( 'immobile-target-namespace-iw' );
2585                 }
2586                 if ( !$nt->isMovable() ) {
2587                         $errors[] = array('immobile-target-namespace', $nt->getNsText() );
2588                 }
2589
2590                 $oldid = $this->getArticleID();
2591                 $newid = $nt->getArticleID();
2592
2593                 if ( strlen( $nt->getDBkey() ) < 1 ) {
2594                         $errors[] = array('articleexists');
2595                 }
2596                 if ( ( '' == $this->getDBkey() ) ||
2597                          ( !$oldid ) ||
2598                      ( '' == $nt->getDBkey() ) ) {
2599                         $errors[] = array('badarticleerror');
2600                 }
2601
2602                 // Image-specific checks
2603                 if( $this->getNamespace() == NS_FILE ) {
2604                         $file = wfLocalFile( $this );
2605                         if( $file->exists() ) {
2606                                 if( $nt->getNamespace() != NS_FILE ) {
2607                                         $errors[] = array('imagenocrossnamespace');
2608                                 }
2609                                 if( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
2610                                         $errors[] = array('imageinvalidfilename');
2611                                 }
2612                                 if( !File::checkExtensionCompatibility( $file, $nt->getDBKey() ) ) {
2613                                         $errors[] = array('imagetypemismatch');
2614                                 }
2615                         }
2616                 }
2617
2618                 if ( $auth ) {
2619                         $errors = wfMergeErrorArrays( $errors,
2620                                 $this->getUserPermissionsErrors('move', $wgUser),
2621                                 $this->getUserPermissionsErrors('edit', $wgUser),
2622                                 $nt->getUserPermissionsErrors('move-target', $wgUser),
2623                                 $nt->getUserPermissionsErrors('edit', $wgUser) );
2624                 }
2625
2626                 $match = EditPage::matchSpamRegex( $reason );
2627                 if( $match !== false ) {
2628                         // This is kind of lame, won't display nice
2629                         $errors[] = array('spamprotectiontext');
2630                 }
2631
2632                 $err = null;
2633                 if( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
2634                         $errors[] = array('hookaborted', $err);
2635                 }
2636
2637                 # The move is allowed only if (1) the target doesn't exist, or
2638                 # (2) the target is a redirect to the source, and has no history
2639                 # (so we can undo bad moves right after they're done).
2640
2641                 if ( 0 != $newid ) { # Target exists; check for validity
2642                         if ( ! $this->isValidMoveTarget( $nt ) ) {
2643                                 $errors[] = array('articleexists');
2644                         }
2645                 } else {
2646                         $tp = $nt->getTitleProtection();
2647                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
2648                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
2649                                 $errors[] = array('cantmove-titleprotected');
2650                         }
2651                 }
2652                 if(empty($errors))
2653                         return true;
2654                 return $errors;
2655         }
2656
2657         /**
2658          * Move a title to a new location
2659          * @param &$nt \type{Title} the new title
2660          * @param $auth \type{\bool} indicates whether $wgUser's permissions
2661          *      should be checked
2662          * @param $reason \type{\string} The reason for the move
2663          * @param $createRedirect \type{\bool} Whether to create a redirect from the old title to the new title.
2664          *  Ignored if the user doesn't have the suppressredirect right.
2665          * @return \type{\mixed} true on success, getUserPermissionsErrors()-like array on failure
2666          */
2667         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
2668                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
2669                 if( is_array( $err ) ) {
2670                         return $err;
2671                 }
2672
2673                 $pageid = $this->getArticleID();
2674                 $protected = $this->isProtected();
2675                 if( $nt->exists() ) {
2676                         $err = $this->moveOverExistingRedirect( $nt, $reason, $createRedirect );
2677                         $pageCountChange = ($createRedirect ? 0 : -1);
2678                 } else { # Target didn't exist, do normal move.
2679                         $err = $this->moveToNewTitle( $nt, $reason, $createRedirect );
2680                         $pageCountChange = ($createRedirect ? 1 : 0);
2681                 }
2682
2683                 if( is_array( $err ) ) {
2684                         return $err;
2685                 }
2686                 $redirid = $this->getArticleID();
2687
2688                 // Category memberships include a sort key which may be customized.
2689                 // If it's left as the default (the page title), we need to update
2690                 // the sort key to match the new title.
2691                 //
2692                 // Be careful to avoid resetting cl_timestamp, which may disturb
2693                 // time-based lists on some sites.
2694                 //
2695                 // Warning -- if the sort key is *explicitly* set to the old title,
2696                 // we can't actually distinguish it from a default here, and it'll
2697                 // be set to the new title even though it really shouldn't.
2698                 // It'll get corrected on the next edit, but resetting cl_timestamp.
2699                 $dbw = wfGetDB( DB_MASTER );
2700                 $dbw->update( 'categorylinks',
2701                         array(
2702                                 'cl_sortkey' => $nt->getPrefixedText(),
2703                                 'cl_timestamp=cl_timestamp' ),
2704                         array(
2705                                 'cl_from' => $pageid,
2706                                 'cl_sortkey' => $this->getPrefixedText() ),
2707                         __METHOD__ );
2708
2709                 if( $protected ) {
2710                         # Protect the redirect title as the title used to be...
2711                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
2712                                 array(
2713                                         'pr_page'    => $redirid,
2714                                         'pr_type'    => 'pr_type',
2715                                         'pr_level'   => 'pr_level',
2716                                         'pr_cascade' => 'pr_cascade',
2717                                         'pr_user'    => 'pr_user',
2718                                         'pr_expiry'  => 'pr_expiry'
2719                                 ),
2720                                 array( 'pr_page' => $pageid ),
2721                                 __METHOD__,
2722                                 array( 'IGNORE' )
2723                         );
2724                         # Update the protection log
2725                         $log = new LogPage( 'protect' );
2726                         $comment = wfMsgForContent( 'prot_1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
2727                         if( $reason ) $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
2728                         $log->addEntry( 'move_prot', $nt, $comment, array($this->getPrefixedText()) ); // FIXME: $params?
2729                 }
2730
2731                 # Update watchlists
2732                 $oldnamespace = $this->getNamespace() & ~1;
2733                 $newnamespace = $nt->getNamespace() & ~1;
2734                 $oldtitle = $this->getDBkey();
2735                 $newtitle = $nt->getDBkey();
2736
2737                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
2738                         WatchedItem::duplicateEntries( $this, $nt );
2739                 }
2740
2741                 # Update search engine
2742                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
2743                 $u->doUpdate();
2744                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
2745                 $u->doUpdate();
2746
2747                 # Update site_stats
2748                 if( $this->isContentPage() && !$nt->isContentPage() ) {
2749                         # No longer a content page
2750                         # Not viewed, edited, removing
2751                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange );
2752                 } elseif( !$this->isContentPage() && $nt->isContentPage() ) {
2753                         # Now a content page
2754                         # Not viewed, edited, adding
2755                         $u = new SiteStatsUpdate( 0, 1, +1, $pageCountChange );
2756                 } elseif( $pageCountChange ) {
2757                         # Redirect added
2758                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
2759                 } else {
2760                         # Nothing special
2761                         $u = false;
2762                 }
2763                 if( $u )
2764                         $u->doUpdate();
2765                 # Update message cache for interface messages
2766                 if( $nt->getNamespace() == NS_MEDIAWIKI ) {
2767                         global $wgMessageCache;
2768                         $oldarticle = new Article( $this );
2769                         $wgMessageCache->replace( $this->getDBkey(), $oldarticle->getContent() );
2770                         $newarticle = new Article( $nt );
2771                         $wgMessageCache->replace( $nt->getDBkey(), $newarticle->getContent() );
2772                 }
2773
2774                 global $wgUser;
2775                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
2776                 return true;
2777         }
2778
2779         /**
2780          * Move page to a title which is at present a redirect to the
2781          * source page
2782          *
2783          * @param &$nt \type{Title} the page to move to, which should currently
2784          *      be a redirect
2785          * @param $reason \type{\string} The reason for the move
2786          * @param $createRedirect \type{\bool} Whether to leave a redirect at the old title.
2787          *  Ignored if the user doesn't have the suppressredirect right
2788          */
2789         private function moveOverExistingRedirect( &$nt, $reason = '', $createRedirect = true ) {
2790                 global $wgUseSquid, $wgUser;
2791                 $fname = 'Title::moveOverExistingRedirect';
2792                 $comment = wfMsgForContent( '1movedto2_redir', $this->getPrefixedText(), $nt->getPrefixedText() );
2793
2794                 if ( $reason ) {
2795                         $comment .= ": $reason";
2796                 }
2797
2798                 $now = wfTimestampNow();
2799                 $newid = $nt->getArticleID();
2800                 $oldid = $this->getArticleID();
2801                 $latest = $this->getLatestRevID();
2802
2803                 $dbw = wfGetDB( DB_MASTER );
2804
2805                 # Delete the old redirect. We don't save it to history since
2806                 # by definition if we've got here it's rather uninteresting.
2807                 # We have to remove it so that the next step doesn't trigger
2808                 # a conflict on the unique namespace+title index...
2809                 $dbw->delete( 'page', array( 'page_id' => $newid ), $fname );
2810                 if ( !$dbw->cascadingDeletes() ) {
2811                         $dbw->delete( 'revision', array( 'rev_page' => $newid ), __METHOD__ );
2812                         global $wgUseTrackbacks;
2813                         if ($wgUseTrackbacks)
2814                                 $dbw->delete( 'trackbacks', array( 'tb_page' => $newid ), __METHOD__ );
2815                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
2816                         $dbw->delete( 'imagelinks', array( 'il_from' => $newid ), __METHOD__ );
2817                         $dbw->delete( 'categorylinks', array( 'cl_from' => $newid ), __METHOD__ );
2818                         $dbw->delete( 'templatelinks', array( 'tl_from' => $newid ), __METHOD__ );
2819                         $dbw->delete( 'externallinks', array( 'el_from' => $newid ), __METHOD__ );
2820                         $dbw->delete( 'langlinks', array( 'll_from' => $newid ), __METHOD__ );
2821                         $dbw->delete( 'redirect', array( 'rd_from' => $newid ), __METHOD__ );
2822                 }
2823
2824                 # Save a null revision in the page's history notifying of the move
2825                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
2826                 $nullRevId = $nullRevision->insertOn( $dbw );
2827
2828                 $article = new Article( $this );
2829                 wfRunHooks( 'NewRevisionFromEditComplete', array($article, $nullRevision, $latest, $wgUser) );
2830
2831                 # Change the name of the target page:
2832                 $dbw->update( 'page',
2833                         /* SET */ array(
2834                                 'page_touched'   => $dbw->timestamp($now),
2835                                 'page_namespace' => $nt->getNamespace(),
2836                                 'page_title'     => $nt->getDBkey(),
2837                                 'page_latest'    => $nullRevId,
2838                         ),
2839                         /* WHERE */ array( 'page_id' => $oldid ),
2840                         $fname
2841                 );
2842                 $nt->resetArticleID( $oldid );
2843
2844                 # Recreate the redirect, this time in the other direction.
2845                 if( $createRedirect || !$wgUser->isAllowed('suppressredirect') ) {
2846                         $mwRedir = MagicWord::get( 'redirect' );
2847                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
2848                         $redirectArticle = new Article( $this );
2849                         $newid = $redirectArticle->insertOn( $dbw );
2850                         $redirectRevision = new Revision( array(
2851                                 'page'    => $newid,
2852                                 'comment' => $comment,
2853                                 'text'    => $redirectText ) );
2854                         $redirectRevision->insertOn( $dbw );
2855                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
2856
2857                         wfRunHooks( 'NewRevisionFromEditComplete', array($redirectArticle, $redirectRevision, false, $wgUser) );
2858
2859                         # Now, we record the link from the redirect to the new title.
2860                         # It should have no other outgoing links...
2861                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), $fname );
2862                         $dbw->insert( 'pagelinks',
2863                                 array(
2864                                         'pl_from'      => $newid,
2865                                         'pl_namespace' => $nt->getNamespace(),
2866                                         'pl_title'     => $nt->getDBkey() ),
2867                                 $fname );
2868                         $redirectSuppressed = false;
2869                 } else {
2870                         $this->resetArticleID( 0 );
2871                         $redirectSuppressed = true;
2872                 }
2873
2874                 # Move an image if this is a file
2875                 if( $this->getNamespace() == NS_FILE ) {
2876                         $file = wfLocalFile( $this );
2877                         if( $file->exists() ) {
2878                                 $status = $file->move( $nt );
2879                                 if( !$status->isOk() ) {
2880                                         $dbw->rollback();
2881                                         return $status->getErrorsArray();
2882                                 }
2883                         }
2884                 }
2885
2886                 # Log the move
2887                 $log = new LogPage( 'move' );
2888                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText(), 2 => $redirectSuppressed ) );
2889
2890                 # Purge squid
2891                 if ( $wgUseSquid ) {
2892                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
2893                         $u = new SquidUpdate( $urls );
2894                         $u->doUpdate();
2895                 }
2896
2897         }
2898
2899         /**
2900          * Move page to non-existing title.
2901          * @param &$nt \type{Title} the new Title
2902          * @param $reason \type{\string} The reason for the move
2903          * @param $createRedirect \type{\bool} Whether to create a redirect from the old title to the new title
2904          *  Ignored if the user doesn't have the suppressredirect right
2905          */
2906         private function moveToNewTitle( &$nt, $reason = '', $createRedirect = true ) {
2907                 global $wgUseSquid, $wgUser;
2908                 $fname = 'MovePageForm::moveToNewTitle';
2909                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
2910                 if ( $reason ) {
2911                         $comment .= wfMsgExt( 'colon-separator',
2912                                 array( 'escapenoentities', 'content' ) );
2913                         $comment .= $reason;
2914                 }
2915
2916                 $newid = $nt->getArticleID();
2917                 $oldid = $this->getArticleID();
2918                 $latest = $this->getLatestRevId();
2919
2920                 $dbw = wfGetDB( DB_MASTER );
2921                 $now = $dbw->timestamp();
2922
2923                 # Save a null revision in the page's history notifying of the move
2924                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
2925                 $nullRevId = $nullRevision->insertOn( $dbw );
2926
2927                 $article = new Article( $this );
2928                 wfRunHooks( 'NewRevisionFromEditComplete', array($article, $nullRevision, $latest, $wgUser) );
2929
2930                 # Rename page entry
2931                 $dbw->update( 'page',
2932                         /* SET */ array(
2933                                 'page_touched'   => $now,
2934                                 'page_namespace' => $nt->getNamespace(),
2935                                 'page_title'     => $nt->getDBkey(),
2936                                 'page_latest'    => $nullRevId,
2937                         ),
2938                         /* WHERE */ array( 'page_id' => $oldid ),
2939                         $fname
2940                 );
2941                 $nt->resetArticleID( $oldid );
2942
2943                 if( $createRedirect || !$wgUser->isAllowed('suppressredirect') ) {
2944                         # Insert redirect
2945                         $mwRedir = MagicWord::get( 'redirect' );
2946                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
2947                         $redirectArticle = new Article( $this );
2948                         $newid = $redirectArticle->insertOn( $dbw );
2949                         $redirectRevision = new Revision( array(
2950                                 'page'    => $newid,
2951                                 'comment' => $comment,
2952                                 'text'    => $redirectText ) );
2953                         $redirectRevision->insertOn( $dbw );
2954                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
2955
2956                         wfRunHooks( 'NewRevisionFromEditComplete', array($redirectArticle, $redirectRevision, false, $wgUser) );
2957
2958                         # Record the just-created redirect's linking to the page
2959                         $dbw->insert( 'pagelinks',
2960                                 array(
2961                                         'pl_from'      => $newid,
2962                                         'pl_namespace' => $nt->getNamespace(),
2963                                         'pl_title'     => $nt->getDBkey() ),
2964                                 $fname );
2965                         $redirectSuppressed = false;
2966                 } else {
2967                         $this->resetArticleID( 0 );
2968                         $redirectSuppressed = true;
2969                 }
2970
2971                 # Move an image if this is a file
2972                 if( $this->getNamespace() == NS_FILE ) {
2973                         $file = wfLocalFile( $this );
2974                         if( $file->exists() ) {
2975                                 $status = $file->move( $nt );
2976                                 if( !$status->isOk() ) {
2977                                         $dbw->rollback();
2978                                         return $status->getErrorsArray();
2979                                 }
2980                         }
2981                 }
2982
2983                 # Log the move
2984                 $log = new LogPage( 'move' );
2985                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText(), 2 => $redirectSuppressed ) );
2986
2987                 # Purge caches as per article creation
2988                 Article::onArticleCreate( $nt );
2989
2990                 # Purge old title from squid
2991                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
2992                 $this->purgeSquid();
2993
2994         }
2995
2996         /**
2997          * Move this page's subpages to be subpages of $nt
2998          * @param $nt Title Move target
2999          * @param $auth bool Whether $wgUser's permissions should be checked
3000          * @param $reason string The reason for the move
3001          * @param $createRedirect bool Whether to create redirects from the old subpages to the new ones
3002          *  Ignored if the user doesn't have the 'suppressredirect' right
3003          * @return mixed array with old page titles as keys, and strings (new page titles) or
3004          *  arrays (errors) as values, or an error array with numeric indices if no pages were moved
3005          */
3006         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3007                 global $wgUser, $wgMaximumMovedPages;
3008                 // Check permissions
3009                 if( !$this->userCan( 'move-subpages' ) )
3010                         return array( 'cant-move-subpages' );
3011                 // Do the source and target namespaces support subpages?
3012                 if( !MWNamespace::hasSubpages( $this->getNamespace() ) )
3013                         return array( 'namespace-nosubpages',
3014                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3015                 if( !MWNamespace::hasSubpages( $nt->getNamespace() ) )
3016                         return array( 'namespace-nosubpages',
3017                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3018
3019                 $subpages = $this->getSubpages($wgMaximumMovedPages + 1);
3020                 $retval = array();
3021                 $count = 0;
3022                 foreach( $subpages as $oldSubpage ) {
3023                         $count++;
3024                         if( $count > $wgMaximumMovedPages ) {
3025                                 $retval[$oldSubpage->getPrefixedTitle()] =
3026                                                 array( 'movepage-max-pages',
3027                                                         $wgMaximumMovedPages );
3028                                 break;
3029                         }
3030
3031                         if( $oldSubpage->getArticleId() == $this->getArticleId() )
3032                                 // When moving a page to a subpage of itself,
3033                                 // don't move it twice
3034                                 continue;
3035                         $newPageName = preg_replace(
3036                                         '#^'.preg_quote( $this->getDBKey(), '#' ).'#',
3037                                         $nt->getDBKey(), $oldSubpage->getDBKey() );
3038                         if( $oldSubpage->isTalkPage() ) {
3039                                 $newNs = $nt->getTalkPage()->getNamespace();
3040                         } else {
3041                                 $newNs = $nt->getSubjectPage()->getNamespace();
3042                         }
3043                         # Bug 14385: we need makeTitleSafe because the new page names may
3044                         # be longer than 255 characters.
3045                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3046
3047                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3048                         if( $success === true ) {
3049                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3050                         } else {
3051                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3052                         }
3053                 }
3054                 return $retval;
3055         }
3056
3057         /**
3058          * Checks if this page is just a one-rev redirect.
3059          * Adds lock, so don't use just for light purposes.
3060          *
3061          * @return \type{\bool} TRUE or FALSE
3062          */
3063         public function isSingleRevRedirect() {
3064                 $dbw = wfGetDB( DB_MASTER );
3065                 # Is it a redirect?
3066                 $row = $dbw->selectRow( 'page',
3067                         array( 'page_is_redirect', 'page_latest', 'page_id' ),
3068                         $this->pageCond(),
3069                         __METHOD__,
3070                         array( 'FOR UPDATE' )
3071                 );
3072                 # Cache some fields we may want
3073                 $this->mArticleID = $row ? intval($row->page_id) : 0;
3074                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3075                 $this->mLatestID = $row ? intval($row->page_latest) : false;
3076                 if( !$this->mRedirect ) {
3077                         return false;
3078                 }
3079                 # Does the article have a history?
3080                 $row = $dbw->selectField( array( 'page', 'revision'),
3081                         'rev_id',
3082                         array( 'page_namespace' => $this->getNamespace(),
3083                                 'page_title' => $this->getDBkey(),
3084                                 'page_id=rev_page',
3085                                 'page_latest != rev_id'
3086                         ),
3087                         __METHOD__,
3088                         array( 'FOR UPDATE' )
3089                 );
3090                 # Return true if there was no history
3091                 return ($row === false);
3092         }
3093
3094         /**
3095          * Checks if $this can be moved to a given Title
3096          * - Selects for update, so don't call it unless you mean business
3097          *
3098          * @param &$nt \type{Title} the new title to check
3099          * @return \type{\bool} TRUE or FALSE
3100          */
3101         public function isValidMoveTarget( $nt ) {
3102                 $dbw = wfGetDB( DB_MASTER );
3103                 # Is it an existsing file?
3104                 if( $nt->getNamespace() == NS_FILE ) {
3105                         $file = wfLocalFile( $nt );
3106                         if( $file->exists() ) {
3107                                 wfDebug( __METHOD__ . ": file exists\n" );
3108                                 return false;
3109                         }
3110                 }
3111                 # Is it a redirect with no history?
3112                 if( !$nt->isSingleRevRedirect() ) {
3113                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3114                         return false;
3115                 }
3116                 # Get the article text
3117                 $rev = Revision::newFromTitle( $nt );
3118                 $text = $rev->getText();
3119                 # Does the redirect point to the source?
3120                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3121                 $m = array();
3122                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
3123                         $redirTitle = Title::newFromText( $m[1] );
3124                         if( !is_object( $redirTitle ) ||
3125                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3126                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
3127                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3128                                 return false;
3129                         }
3130                 } else {
3131                         # Fail safe
3132                         wfDebug( __METHOD__ . ": failsafe\n" );
3133                         return false;
3134                 }
3135                 return true;
3136         }
3137
3138         /**
3139          * Can this title be added to a user's watchlist?
3140          *
3141          * @return \type{\bool} TRUE or FALSE
3142          */
3143         public function isWatchable() {
3144                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
3145         }
3146
3147         /**
3148          * Get categories to which this Title belongs and return an array of
3149          * categories' names.
3150          *
3151          * @return \type{\array} array an array of parents in the form:
3152          *      $parent => $currentarticle
3153          */
3154         public function getParentCategories() {
3155                 global $wgContLang;
3156
3157                 $titlekey = $this->getArticleId();
3158                 $dbr = wfGetDB( DB_SLAVE );
3159                 $categorylinks = $dbr->tableName( 'categorylinks' );
3160
3161                 # NEW SQL
3162                 $sql = "SELECT * FROM $categorylinks"
3163                      ." WHERE cl_from='$titlekey'"
3164                          ." AND cl_from <> '0'"
3165                          ." ORDER BY cl_sortkey";
3166
3167                 $res = $dbr->query( $sql );
3168
3169                 if( $dbr->numRows( $res ) > 0 ) {
3170                         foreach( $res as $row )
3171                                 //$data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
3172                                 $data[$wgContLang->getNSText( NS_CATEGORY ).':'.$row->cl_to] = $this->getFullText();
3173                         $dbr->freeResult( $res );
3174                 } else {
3175                         $data = array();
3176                 }
3177                 return $data;
3178         }
3179
3180         /**
3181          * Get a tree of parent categories
3182          * @param $children \type{\array} an array with the children in the keys, to check for circular refs
3183          * @return \type{\array} Tree of parent categories
3184          */
3185         public function getParentCategoryTree( $children = array() ) {
3186                 $stack = array();
3187                 $parents = $this->getParentCategories();
3188
3189                 if( $parents ) {
3190                         foreach( $parents as $parent => $current ) {
3191                                 if ( array_key_exists( $parent, $children ) ) {
3192                                         # Circular reference
3193                                         $stack[$parent] = array();
3194                                 } else {
3195                                         $nt = Title::newFromText($parent);
3196                                         if ( $nt ) {
3197                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array($parent => 1) );
3198                                         }
3199                                 }
3200                         }
3201                         return $stack;
3202                 } else {
3203                         return array();
3204                 }
3205         }
3206
3207
3208         /**
3209          * Get an associative array for selecting this title from
3210          * the "page" table
3211          *
3212          * @return \type{\array} Selection array
3213          */
3214         public function pageCond() {
3215                 if( $this->mArticleID > 0 ) {
3216                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
3217                         return array( 'page_id' => $this->mArticleID );
3218                 } else {
3219                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
3220                 }
3221         }
3222
3223         /**
3224          * Get the revision ID of the previous revision
3225          *
3226          * @param $revId \type{\int} Revision ID. Get the revision that was before this one.
3227          * @param $flags \type{\int} GAID_FOR_UPDATE
3228          * @return \twotypes{\int,\bool} Old revision ID, or FALSE if none exists
3229          */
3230         public function getPreviousRevisionID( $revId, $flags=0 ) {
3231                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3232                 return $db->selectField( 'revision', 'rev_id',
3233                         array(
3234                                 'rev_page' => $this->getArticleId($flags),
3235                                 'rev_id < ' . intval( $revId )
3236                         ),
3237                         __METHOD__,
3238                         array( 'ORDER BY' => 'rev_id DESC' )
3239                 );
3240         }
3241
3242         /**
3243          * Get the revision ID of the next revision
3244          *
3245          * @param $revId \type{\int} Revision ID. Get the revision that was after this one.
3246          * @param $flags \type{\int} GAID_FOR_UPDATE
3247          * @return \twotypes{\int,\bool} Next revision ID, or FALSE if none exists
3248          */
3249         public function getNextRevisionID( $revId, $flags=0 ) {
3250                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3251                 return $db->selectField( 'revision', 'rev_id',
3252                         array(
3253                                 'rev_page' => $this->getArticleId($flags),
3254                                 'rev_id > ' . intval( $revId )
3255                         ),
3256                         __METHOD__,
3257                         array( 'ORDER BY' => 'rev_id' )
3258                 );
3259         }
3260
3261         /**
3262          * Get the first revision of the page
3263          *
3264          * @param $flags \type{\int} GAID_FOR_UPDATE
3265          * @return Revision (or NULL if page doesn't exist)
3266          */
3267         public function getFirstRevision( $flags=0 ) {
3268                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3269                 $pageId = $this->getArticleId($flags);
3270                 if( !$pageId ) return NULL;
3271                 $row = $db->selectRow( 'revision', '*',
3272                         array( 'rev_page' => $pageId ),
3273                         __METHOD__,
3274                         array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
3275                 );
3276                 if( !$row ) {
3277                         return NULL;
3278                 } else {
3279                         return new Revision( $row );
3280                 }
3281         }
3282
3283         /**
3284          * Check if this is a new page
3285          *
3286          * @return bool
3287          */
3288         public function isNewPage() {
3289                 $dbr = wfGetDB( DB_SLAVE );
3290                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
3291         }
3292
3293         /**
3294          * Get the oldest revision timestamp of this page
3295          *
3296          * @return string, MW timestamp
3297          */
3298         public function getEarliestRevTime() {
3299                 $dbr = wfGetDB( DB_SLAVE );
3300                 if( $this->exists() ) {
3301                         $min = $dbr->selectField( 'revision',
3302                                 'MIN(rev_timestamp)',
3303                                 array( 'rev_page' => $this->getArticleId() ),
3304                                 __METHOD__ );
3305                         return wfTimestampOrNull( TS_MW, $min );
3306                 }
3307                 return null;
3308         }
3309
3310         /**
3311          * Get the number of revisions between the given revision IDs.
3312          * Used for diffs and other things that really need it.
3313          *
3314          * @param $old \type{\int} Revision ID.
3315          * @param $new \type{\int} Revision ID.
3316          * @return \type{\int} Number of revisions between these IDs.
3317          */
3318         public function countRevisionsBetween( $old, $new ) {
3319                 $dbr = wfGetDB( DB_SLAVE );
3320                 return $dbr->selectField( 'revision', 'count(*)',
3321                         'rev_page = ' . intval( $this->getArticleId() ) .
3322                         ' AND rev_id > ' . intval( $old ) .
3323                         ' AND rev_id < ' . intval( $new ),
3324                         __METHOD__,
3325                         array( 'USE INDEX' => 'PRIMARY' ) );
3326         }
3327
3328         /**
3329          * Compare with another title.
3330          *
3331          * @param \type{Title} $title
3332          * @return \type{\bool} TRUE or FALSE
3333          */
3334         public function equals( Title $title ) {
3335                 // Note: === is necessary for proper matching of number-like titles.
3336                 return $this->getInterwiki() === $title->getInterwiki()
3337                         && $this->getNamespace() == $title->getNamespace()
3338                         && $this->getDBkey() === $title->getDBkey();
3339         }
3340
3341         /**
3342          * Callback for usort() to do title sorts by (namespace, title)
3343          */
3344         static function compare( $a, $b ) {
3345                 if( $a->getNamespace() == $b->getNamespace() ) {
3346                         return strcmp( $a->getText(), $b->getText() );
3347                 } else {
3348                         return $a->getNamespace() - $b->getNamespace();
3349                 }
3350         }
3351
3352         /**
3353          * Return a string representation of this title
3354          *
3355          * @return \type{\string} String representation of this title
3356          */
3357         public function __toString() {
3358                 return $this->getPrefixedText();
3359         }
3360
3361         /**
3362          * Check if page exists.  For historical reasons, this function simply
3363          * checks for the existence of the title in the page table, and will
3364          * thus return false for interwiki links, special pages and the like.
3365          * If you want to know if a title can be meaningfully viewed, you should
3366          * probably call the isKnown() method instead.
3367          *
3368          * @return \type{\bool} TRUE or FALSE
3369          */
3370         public function exists() {
3371                 return $this->getArticleId() != 0;
3372         }
3373
3374         /**
3375          * Should links to this title be shown as potentially viewable (i.e. as
3376          * "bluelinks"), even if there's no record by this title in the page
3377          * table?
3378          *
3379          * This function is semi-deprecated for public use, as well as somewhat
3380          * misleadingly named.  You probably just want to call isKnown(), which
3381          * calls this function internally.
3382          *
3383          * (ISSUE: Most of these checks are cheap, but the file existence check
3384          * can potentially be quite expensive.  Including it here fixes a lot of
3385          * existing code, but we might want to add an optional parameter to skip
3386          * it and any other expensive checks.)
3387          *
3388          * @return \type{\bool} TRUE or FALSE
3389          */
3390         public function isAlwaysKnown() {
3391                 if( $this->mInterwiki != '' ) {
3392                         return true;  // any interwiki link might be viewable, for all we know
3393                 }
3394                 switch( $this->mNamespace ) {
3395                 case NS_MEDIA:
3396                 case NS_FILE:
3397                         return wfFindFile( $this );  // file exists, possibly in a foreign repo
3398                 case NS_SPECIAL:
3399                         return SpecialPage::exists( $this->getDBKey() );  // valid special page
3400                 case NS_MAIN:
3401                         return $this->mDbkeyform == '';  // selflink, possibly with fragment
3402                 case NS_MEDIAWIKI:
3403                         // If the page is form Mediawiki:message/lang, calling wfMsgWeirdKey causes
3404                         // the full l10n of that language to be loaded. That takes much memory and
3405                         // isn't needed. So we strip the language part away.
3406                         // Also, extension messages which are not loaded, are shown as red, because
3407                         // we don't call MessageCache::loadAllMessages.
3408                         list( $basename, /* rest */ ) = explode( '/', $this->mDbkeyform, 2 );
3409                         return wfMsgWeirdKey( $basename );  // known system message
3410                 default:
3411                         return false;
3412                 }
3413         }
3414
3415         /**
3416          * Does this title refer to a page that can (or might) be meaningfully
3417          * viewed?  In particular, this function may be used to determine if
3418          * links to the title should be rendered as "bluelinks" (as opposed to
3419          * "redlinks" to non-existent pages).
3420          *
3421          * @return \type{\bool} TRUE or FALSE
3422          */
3423         public function isKnown() {
3424                 return $this->exists() || $this->isAlwaysKnown();
3425         }
3426
3427         /**
3428         * Is this in a namespace that allows actual pages?
3429         *
3430         * @return \type{\bool} TRUE or FALSE
3431         */
3432         public function canExist() {
3433                 return $this->mNamespace >= 0 && $this->mNamespace != NS_MEDIA;
3434         }
3435
3436         /**
3437          * Update page_touched timestamps and send squid purge messages for
3438          * pages linking to this title. May be sent to the job queue depending
3439          * on the number of links. Typically called on create and delete.
3440          */
3441         public function touchLinks() {
3442                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
3443                 $u->doUpdate();
3444
3445                 if ( $this->getNamespace() == NS_CATEGORY ) {
3446                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
3447                         $u->doUpdate();
3448                 }
3449         }
3450
3451         /**
3452          * Get the last touched timestamp
3453          * @param Database $db, optional db
3454          * @return \type{\string} Last touched timestamp
3455          */
3456         public function getTouched( $db = NULL ) {
3457                 $db = isset($db) ? $db : wfGetDB( DB_SLAVE );
3458                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
3459                 return $touched;
3460         }
3461
3462         /**
3463          * Get the timestamp when this page was updated since the user last saw it.
3464          * @param User $user
3465          * @return mixed string/NULL
3466          */
3467         public function getNotificationTimestamp( $user = NULL ) {
3468                 global $wgUser, $wgShowUpdatedMarker;
3469                 // Assume current user if none given
3470                 if( !$user ) $user = $wgUser;
3471                 // Check cache first
3472                 $uid = $user->getId();
3473                 if( isset($this->mNotificationTimestamp[$uid]) ) {
3474                         return $this->mNotificationTimestamp[$uid];
3475                 }
3476                 if( !$uid || !$wgShowUpdatedMarker ) {
3477                         return $this->mNotificationTimestamp[$uid] = false;
3478                 }
3479                 // Don't cache too much!
3480                 if( count($this->mNotificationTimestamp) >= self::CACHE_MAX ) {
3481                         $this->mNotificationTimestamp = array();
3482                 }
3483                 $dbr = wfGetDB( DB_SLAVE );
3484                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
3485                         'wl_notificationtimestamp',
3486                         array( 'wl_namespace' => $this->getNamespace(),
3487                                 'wl_title' => $this->getDBkey(),
3488                                 'wl_user' => $user->getId()
3489                         ),
3490                         __METHOD__
3491                 );
3492                 return $this->mNotificationTimestamp[$uid];
3493         }
3494
3495         /**
3496          * Get the trackback URL for this page
3497          * @return \type{\string} Trackback URL
3498          */
3499         public function trackbackURL() {
3500                 global $wgScriptPath, $wgServer;
3501
3502                 return "$wgServer$wgScriptPath/trackback.php?article="
3503                         . htmlspecialchars(urlencode($this->getPrefixedDBkey()));
3504         }
3505
3506         /**
3507          * Get the trackback RDF for this page
3508          * @return \type{\string} Trackback RDF
3509          */
3510         public function trackbackRDF() {
3511                 $url = htmlspecialchars($this->getFullURL());
3512                 $title = htmlspecialchars($this->getText());
3513                 $tburl = $this->trackbackURL();
3514
3515                 // Autodiscovery RDF is placed in comments so HTML validator
3516                 // won't barf. This is a rather icky workaround, but seems
3517                 // frequently used by this kind of RDF thingy.
3518                 //
3519                 // Spec: http://www.sixapart.com/pronet/docs/trackback_spec
3520                 return "<!--
3521 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
3522          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
3523          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
3524 <rdf:Description
3525    rdf:about=\"$url\"
3526    dc:identifier=\"$url\"
3527    dc:title=\"$title\"
3528    trackback:ping=\"$tburl\" />
3529 </rdf:RDF>
3530 -->";
3531         }
3532
3533         /**
3534          * Generate strings used for xml 'id' names in monobook tabs
3535          * @return \type{\string} XML 'id' name
3536          */
3537         public function getNamespaceKey() {
3538                 global $wgContLang;
3539                 switch ($this->getNamespace()) {
3540                         case NS_MAIN:
3541                         case NS_TALK:
3542                                 return 'nstab-main';
3543                         case NS_USER:
3544                         case NS_USER_TALK:
3545                                 return 'nstab-user';
3546                         case NS_MEDIA:
3547                                 return 'nstab-media';
3548                         case NS_SPECIAL:
3549                                 return 'nstab-special';
3550                         case NS_PROJECT:
3551                         case NS_PROJECT_TALK:
3552                                 return 'nstab-project';
3553                         case NS_FILE:
3554                         case NS_FILE_TALK:
3555                                 return 'nstab-image';
3556                         case NS_MEDIAWIKI:
3557                         case NS_MEDIAWIKI_TALK:
3558                                 return 'nstab-mediawiki';
3559                         case NS_TEMPLATE:
3560                         case NS_TEMPLATE_TALK:
3561                                 return 'nstab-template';
3562                         case NS_HELP:
3563                         case NS_HELP_TALK:
3564                                 return 'nstab-help';
3565                         case NS_CATEGORY:
3566                         case NS_CATEGORY_TALK:
3567                                 return 'nstab-category';
3568                         default:
3569                                 return 'nstab-' . $wgContLang->lc( $this->getSubjectNsText() );
3570                 }
3571         }
3572
3573         /**
3574          * Returns true if this title resolves to the named special page
3575          * @param $name \type{\string} The special page name
3576          */
3577         public function isSpecial( $name ) {
3578                 if ( $this->getNamespace() == NS_SPECIAL ) {
3579                         list( $thisName, /* $subpage */ ) = SpecialPage::resolveAliasWithSubpage( $this->getDBkey() );
3580                         if ( $name == $thisName ) {
3581                                 return true;
3582                         }
3583                 }
3584                 return false;
3585         }
3586
3587         /**
3588          * If the Title refers to a special page alias which is not the local default,
3589          * @return \type{Title} A new Title which points to the local default. Otherwise, returns $this.
3590          */
3591         public function fixSpecialName() {
3592                 if ( $this->getNamespace() == NS_SPECIAL ) {
3593                         $canonicalName = SpecialPage::resolveAlias( $this->mDbkeyform );
3594                         if ( $canonicalName ) {
3595                                 $localName = SpecialPage::getLocalNameFor( $canonicalName );
3596                                 if ( $localName != $this->mDbkeyform ) {
3597                                         return Title::makeTitle( NS_SPECIAL, $localName );
3598                                 }
3599                         }
3600                 }
3601                 return $this;
3602         }
3603
3604         /**
3605          * Is this Title in a namespace which contains content?
3606          * In other words, is this a content page, for the purposes of calculating
3607          * statistics, etc?
3608          *
3609          * @return \type{\bool} TRUE or FALSE
3610          */
3611         public function isContentPage() {
3612                 return MWNamespace::isContent( $this->getNamespace() );
3613         }
3614
3615         /**
3616          * Get all extant redirects to this Title
3617          *
3618          * @param $ns \twotypes{\int,\null} Single namespace to consider;
3619          *            NULL to consider all namespaces
3620          * @return \type{\arrayof{Title}} Redirects to this title
3621          */
3622         public function getRedirectsHere( $ns = null ) {
3623                 $redirs = array();
3624
3625                 $dbr = wfGetDB( DB_SLAVE );
3626                 $where = array(
3627                         'rd_namespace' => $this->getNamespace(),
3628                         'rd_title' => $this->getDBkey(),
3629                         'rd_from = page_id'
3630                 );
3631                 if ( !is_null($ns) ) $where['page_namespace'] = $ns;
3632
3633                 $res = $dbr->select(
3634                         array( 'redirect', 'page' ),
3635                         array( 'page_namespace', 'page_title' ),
3636                         $where,
3637                         __METHOD__
3638                 );
3639
3640
3641                 foreach( $res as $row ) {
3642                         $redirs[] = self::newFromRow( $row );
3643                 }
3644                 return $redirs;
3645         }
3646
3647         /**
3648          * Check if this Title is a valid redirect target
3649          *
3650          * @return \type{\bool} TRUE or FALSE
3651          */
3652         public function isValidRedirectTarget() {
3653                 global $wgInvalidRedirectTargets;
3654
3655                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
3656                 if( $this->isSpecial( 'Userlogout' ) ) {
3657                         return false;
3658                 }
3659
3660                 foreach( $wgInvalidRedirectTargets as $target ) {
3661                         if( $this->isSpecial( $target ) ) {
3662                                 return false;
3663                         }
3664                 }
3665
3666                 return true;
3667         }
3668
3669         /**
3670          * Get a backlink cache object
3671          */
3672         function getBacklinkCache() {
3673                 if ( is_null( $this->mBacklinkCache ) ) {
3674                         $this->mBacklinkCache = new BacklinkCache( $this );
3675                 }
3676                 return $this->mBacklinkCache;
3677         }
3678 }