includes/Title.php

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