includes/Title.php

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