includes/Title.php

   1 <?php
   2 /**
   3  * See title.txt
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 /**
  24  * Represents a title within MediaWiki.
  25  * Optionally may contain an interwiki designation or namespace.
  26  * @note This class can fetch various kinds of data from the database;
  27  *       however, it does so inefficiently.
  28  *
  29  * @internal documentation reviewed 15 Mar 2010
  30  */
  31 class Title {
  32         /** @name Static cache variables */
  33         // @{
  34         static private $titleCache = array();
  35         // @}
  36
  37         /**
  38          * Title::newFromText maintains a cache to avoid expensive re-normalization of
  39          * commonly used titles. On a batch operation this can become a memory leak
  40          * if not bounded. After hitting this many titles reset the cache.
  41          */
  42         const CACHE_MAX = 1000;
  43
  44         /**
  45          * Used to be GAID_FOR_UPDATE define. Used with getArticleID() and friends
  46          * to use the master DB
  47          */
  48         const GAID_FOR_UPDATE = 1;
  49
  50         /**
  51          * @name Private member variables
  52          * Please use the accessor functions instead.
  53          * @private
  54          */
  55         // @{
  56
  57         var $mTextform = '';              // /< Text form (spaces not underscores) of the main part
  58         var $mUrlform = '';               // /< URL-encoded form of the main part
  59         var $mDbkeyform = '';             // /< Main part with underscores
  60         var $mUserCaseDBKey;              // /< DB key with the initial letter in the case specified by the user
  61         var $mNamespace = NS_MAIN;        // /< Namespace index, i.e. one of the NS_xxxx constants
  62         var $mInterwiki = '';             // /< Interwiki prefix (or null string)
  63         var $mFragment;                   // /< Title fragment (i.e. the bit after the #)
  64         var $mArticleID = -1;             // /< Article ID, fetched from the link cache on demand
  65         var $mLatestID = false;           // /< ID of most recent revision
  66         private $mEstimateRevisions;      // /< Estimated number of revisions; null of not loaded
  67         var $mRestrictions = array();     // /< Array of groups allowed to edit this article
  68         var $mOldRestrictions = false;
  69         var $mCascadeRestriction;         ///< Cascade restrictions on this page to included templates and images?
  70         var $mCascadingRestrictions;      // Caching the results of getCascadeProtectionSources
  71         var $mRestrictionsExpiry = array(); ///< When do the restrictions on this page expire?
  72         var $mHasCascadingRestrictions;   ///< Are cascading restrictions in effect on this page?
  73         var $mCascadeSources;             ///< Where are the cascading restrictions coming from on this page?
  74         var $mRestrictionsLoaded = false; ///< Boolean for initialisation on demand
  75         var $mPrefixedText;               ///< Text form including namespace/interwiki, initialised on demand
  76         var $mTitleProtection;            ///< Cached value for getTitleProtection (create protection)
  77         # Don't change the following default, NS_MAIN is hardcoded in several
  78         # places.  See bug 696.
  79         var $mDefaultNamespace = NS_MAIN; // /< Namespace index when there is no namespace
  80                                                                           # Zero except in {{transclusion}} tags
  81         var $mWatched = null;             // /< Is $wgUser watching this page? null if unfilled, accessed through userIsWatching()
  82         var $mLength = -1;                // /< The page length, 0 for special pages
  83         var $mRedirect = null;            // /< Is the article at this title a redirect?
  84         var $mNotificationTimestamp = array(); // /< Associative array of user ID -> timestamp/false
  85         var $mBacklinkCache = null;       // /< Cache of links to this title
  86         // @}
  87
  88
  89         /**
  90          * Constructor
  91          */
  92         /*protected*/ function __construct() { }
  93
  94         /**
  95          * Create a new Title from a prefixed DB key
  96          *
  97          * @param $key String the database key, which has underscores
  98          *      instead of spaces, possibly including namespace and
  99          *      interwiki prefixes
 100          * @return Title, or NULL on an error
 101          */
 102         public static function newFromDBkey( $key ) {
 103                 $t = new Title();
 104                 $t->mDbkeyform = $key;
 105                 if ( $t->secureAndSplit() ) {
 106                         return $t;
 107                 } else {
 108                         return null;
 109                 }
 110         }
 111
 112         /**
 113          * Create a new Title from text, such as what one would find in a link. De-
 114          * codes any HTML entities in the text.
 115          *
 116          * @param $text String the link text; spaces, prefixes, and an
 117          *   initial ':' indicating the main namespace are accepted.
 118          * @param $defaultNamespace Int the namespace to use if none is speci-
 119          *   fied by a prefix.  If you want to force a specific namespace even if
 120          *   $text might begin with a namespace prefix, use makeTitle() or
 121          *   makeTitleSafe().
 122          * @return Title, or null on an error.
 123          */
 124         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 125                 if ( is_object( $text ) ) {
 126                         throw new MWException( 'Title::newFromText given an object' );
 127                 }
 128
 129                 /**
 130                  * Wiki pages often contain multiple links to the same page.
 131                  * Title normalization and parsing can become expensive on
 132                  * pages with many links, so we can save a little time by
 133                  * caching them.
 134                  *
 135                  * In theory these are value objects and won't get changed...
 136                  */
 137                 if ( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 138                         return Title::$titleCache[$text];
 139                 }
 140
 141                 # Convert things like &eacute; &#257; or &#x3017; into normalized (bug 14952) text
 142                 $filteredText = Sanitizer::decodeCharReferencesAndNormalize( $text );
 143
 144                 $t = new Title();
 145                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 146                 $t->mDefaultNamespace = $defaultNamespace;
 147
 148                 static $cachedcount = 0 ;
 149                 if ( $t->secureAndSplit() ) {
 150                         if ( $defaultNamespace == NS_MAIN ) {
 151                                 if ( $cachedcount >= self::CACHE_MAX ) {
 152                                         # Avoid memory leaks on mass operations...
 153                                         Title::$titleCache = array();
 154                                         $cachedcount = 0;
 155                                 }
 156                                 $cachedcount++;
 157                                 Title::$titleCache[$text] =& $t;
 158                         }
 159                         return $t;
 160                 } else {
 161                         $ret = null;
 162                         return $ret;
 163                 }
 164         }
 165
 166         /**
 167          * THIS IS NOT THE FUNCTION YOU WANT. Use Title::newFromText().
 168          *
 169          * Example of wrong and broken code:
 170          * $title = Title::newFromURL( $wgRequest->getVal( 'title' ) );
 171          *
 172          * Example of right code:
 173          * $title = Title::newFromText( $wgRequest->getVal( 'title' ) );
 174          *
 175          * Create a new Title from URL-encoded text. Ensures that
 176          * the given title's length does not exceed the maximum.
 177          *
 178          * @param $url String the title, as might be taken from a URL
 179          * @return Title the new object, or NULL on an error
 180          */
 181         public static function newFromURL( $url ) {
 182                 global $wgLegalTitleChars;
 183                 $t = new Title();
 184
 185                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 186                 # but some URLs used it as a space replacement and they still come
 187                 # from some external search tools.
 188                 if ( strpos( $wgLegalTitleChars, '+' ) === false ) {
 189                         $url = str_replace( '+', ' ', $url );
 190                 }
 191
 192                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 193                 if ( $t->secureAndSplit() ) {
 194                         return $t;
 195                 } else {
 196                         return null;
 197                 }
 198         }
 199
 200         /**
 201          * Create a new Title from an article ID
 202          *
 203          * @param $id Int the page_id corresponding to the Title to create
 204          * @param $flags Int use Title::GAID_FOR_UPDATE to use master
 205          * @return Title the new object, or NULL on an error
 206          */
 207         public static function newFromID( $id, $flags = 0 ) {
 208                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
 209                 $row = $db->selectRow( 'page', '*', array( 'page_id' => $id ), __METHOD__ );
 210                 if ( $row !== false ) {
 211                         $title = Title::newFromRow( $row );
 212                 } else {
 213                         $title = null;
 214                 }
 215                 return $title;
 216         }
 217
 218         /**
 219          * Make an array of titles from an array of IDs
 220          *
 221          * @param $ids Array of Int Array of IDs
 222          * @return Array of Titles
 223          */
 224         public static function newFromIDs( $ids ) {
 225                 if ( !count( $ids ) ) {
 226                         return array();
 227                 }
 228                 $dbr = wfGetDB( DB_SLAVE );
 229
 230                 $res = $dbr->select(
 231                         'page',
 232                         array(
 233                                 'page_namespace', 'page_title', 'page_id',
 234                                 'page_len', 'page_is_redirect', 'page_latest',
 235                         ),
 236                         array( 'page_id' => $ids ),
 237                         __METHOD__
 238                 );
 239
 240                 $titles = array();
 241                 foreach ( $res as $row ) {
 242                         $titles[] = Title::newFromRow( $row );
 243                 }
 244                 return $titles;
 245         }
 246
 247         /**
 248          * Make a Title object from a DB row
 249          *
 250          * @param $row Object database row (needs at least page_title,page_namespace)
 251          * @return Title corresponding Title
 252          */
 253         public static function newFromRow( $row ) {
 254                 $t = self::makeTitle( $row->page_namespace, $row->page_title );
 255                 $t->loadFromRow( $row );
 256                 return $t;
 257         }
 258
 259         /**
 260          * Load Title object fields from a DB row.
 261          * If false is given, the title will be treated as non-existing.
 262          *
 263          * @param $row Object|bool database row
 264          */
 265         public function loadFromRow( $row ) {
 266                 if ( $row ) { // page found
 267                         if ( isset( $row->page_id ) )
 268                                 $this->mArticleID = (int)$row->page_id;
 269                         if ( isset( $row->page_len ) )
 270                                 $this->mLength = (int)$row->page_len;
 271                         if ( isset( $row->page_is_redirect ) )
 272                                 $this->mRedirect = (bool)$row->page_is_redirect;
 273                         if ( isset( $row->page_latest ) )
 274                                 $this->mLatestID = (int)$row->page_latest;
 275                 } else { // page not found
 276                         $this->mArticleID = 0;
 277                         $this->mLength = 0;
 278                         $this->mRedirect = false;
 279                         $this->mLatestID = 0;
 280                 }
 281         }
 282
 283         /**
 284          * Create a new Title from a namespace index and a DB key.
 285          * It's assumed that $ns and $title are *valid*, for instance when
 286          * they came directly from the database or a special page name.
 287          * For convenience, spaces are converted to underscores so that
 288          * eg user_text fields can be used directly.
 289          *
 290          * @param $ns Int the namespace of the article
 291          * @param $title String the unprefixed database key form
 292          * @param $fragment String the link fragment (after the "#")
 293          * @param $interwiki String the interwiki prefix
 294          * @return Title the new object
 295          */
 296         public static function &makeTitle( $ns, $title, $fragment = '', $interwiki = '' ) {
 297                 $t = new Title();
 298                 $t->mInterwiki = $interwiki;
 299                 $t->mFragment = $fragment;
 300                 $t->mNamespace = $ns = intval( $ns );
 301                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 302                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 303                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 304                 $t->mTextform = str_replace( '_', ' ', $title );
 305                 return $t;
 306         }
 307
 308         /**
 309          * Create a new Title from a namespace index and a DB key.
 310          * The parameters will be checked for validity, which is a bit slower
 311          * than makeTitle() but safer for user-provided data.
 312          *
 313          * @param $ns Int the namespace of the article
 314          * @param $title String database key form
 315          * @param $fragment String the link fragment (after the "#")
 316          * @param $interwiki String interwiki prefix
 317          * @return Title the new object, or NULL on an error
 318          */
 319         public static function makeTitleSafe( $ns, $title, $fragment = '', $interwiki = '' ) {
 320                 $t = new Title();
 321                 $t->mDbkeyform = Title::makeName( $ns, $title, $fragment, $interwiki );
 322                 if ( $t->secureAndSplit() ) {
 323                         return $t;
 324                 } else {
 325                         return null;
 326                 }
 327         }
 328
 329         /**
 330          * Create a new Title for the Main Page
 331          *
 332          * @return Title the new object
 333          */
 334         public static function newMainPage() {
 335                 $title = Title::newFromText( wfMsgForContent( 'mainpage' ) );
 336                 // Don't give fatal errors if the message is broken
 337                 if ( !$title ) {
 338                         $title = Title::newFromText( 'Main Page' );
 339                 }
 340                 return $title;
 341         }
 342
 343         /**
 344          * Extract a redirect destination from a string and return the
 345          * Title, or null if the text doesn't contain a valid redirect
 346          * This will only return the very next target, useful for
 347          * the redirect table and other checks that don't need full recursion
 348          *
 349          * @param $text String: Text with possible redirect
 350          * @return Title: The corresponding Title
 351          */
 352         public static function newFromRedirect( $text ) {
 353                 return self::newFromRedirectInternal( $text );
 354         }
 355
 356         /**
 357          * Extract a redirect destination from a string and return the
 358          * Title, or null if the text doesn't contain a valid redirect
 359          * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
 360          * in order to provide (hopefully) the Title of the final destination instead of another redirect
 361          *
 362          * @param $text String Text with possible redirect
 363          * @return Title
 364          */
 365         public static function newFromRedirectRecurse( $text ) {
 366                 $titles = self::newFromRedirectArray( $text );
 367                 return $titles ? array_pop( $titles ) : null;
 368         }
 369
 370         /**
 371          * Extract a redirect destination from a string and return an
 372          * array of Titles, or null if the text doesn't contain a valid redirect
 373          * The last element in the array is the final destination after all redirects
 374          * have been resolved (up to $wgMaxRedirects times)
 375          *
 376          * @param $text String Text with possible redirect
 377          * @return Array of Titles, with the destination last
 378          */
 379         public static function newFromRedirectArray( $text ) {
 380                 global $wgMaxRedirects;
 381                 $title = self::newFromRedirectInternal( $text );
 382                 if ( is_null( $title ) ) {
 383                         return null;
 384                 }
 385                 // recursive check to follow double redirects
 386                 $recurse = $wgMaxRedirects;
 387                 $titles = array( $title );
 388                 while ( --$recurse > 0 ) {
 389                         if ( $title->isRedirect() ) {
 390                                 $page = WikiPage::factory( $title );
 391                                 $newtitle = $page->getRedirectTarget();
 392                         } else {
 393                                 break;
 394                         }
 395                         // Redirects to some special pages are not permitted
 396                         if ( $newtitle instanceOf Title && $newtitle->isValidRedirectTarget() ) {
 397                                 // the new title passes the checks, so make that our current title so that further recursion can be checked
 398                                 $title = $newtitle;
 399                                 $titles[] = $newtitle;
 400                         } else {
 401                                 break;
 402                         }
 403                 }
 404                 return $titles;
 405         }
 406
 407         /**
 408          * Really extract the redirect destination
 409          * Do not call this function directly, use one of the newFromRedirect* functions above
 410          *
 411          * @param $text String Text with possible redirect
 412          * @return Title
 413          */
 414         protected static function newFromRedirectInternal( $text ) {
 415                 global $wgMaxRedirects;
 416                 if ( $wgMaxRedirects < 1 ) {
 417                         //redirects are disabled, so quit early
 418                         return null;
 419                 }
 420                 $redir = MagicWord::get( 'redirect' );
 421                 $text = trim( $text );
 422                 if ( $redir->matchStartAndRemove( $text ) ) {
 423                         // Extract the first link and see if it's usable
 424                         // Ensure that it really does come directly after #REDIRECT
 425                         // Some older redirects included a colon, so don't freak about that!
 426                         $m = array();
 427                         if ( preg_match( '!^\s*:?\s*\[{2}(.*?)(?:\|.*?)?\]{2}!', $text, $m ) ) {
 428                                 // Strip preceding colon used to "escape" categories, etc.
 429                                 // and URL-decode links
 430                                 if ( strpos( $m[1], '%' ) !== false ) {
 431                                         // Match behavior of inline link parsing here;
 432                                         $m[1] = rawurldecode( ltrim( $m[1], ':' ) );
 433                                 }
 434                                 $title = Title::newFromText( $m[1] );
 435                                 // If the title is a redirect to bad special pages or is invalid, return null
 436                                 if ( !$title instanceof Title || !$title->isValidRedirectTarget() ) {
 437                                         return null;
 438                                 }
 439                                 return $title;
 440                         }
 441                 }
 442                 return null;
 443         }
 444
 445         /**
 446          * Get the prefixed DB key associated with an ID
 447          *
 448          * @param $id Int the page_id of the article
 449          * @return Title an object representing the article, or NULL if no such article was found
 450          */
 451         public static function nameOf( $id ) {
 452                 $dbr = wfGetDB( DB_SLAVE );
 453
 454                 $s = $dbr->selectRow(
 455                         'page',
 456                         array( 'page_namespace', 'page_title' ),
 457                         array( 'page_id' => $id ),
 458                         __METHOD__
 459                 );
 460                 if ( $s === false ) {
 461                         return null;
 462                 }
 463
 464                 $n = self::makeName( $s->page_namespace, $s->page_title );
 465                 return $n;
 466         }
 467
 468         /**
 469          * Get a regex character class describing the legal characters in a link
 470          *
 471          * @return String the list of characters, not delimited
 472          */
 473         public static function legalChars() {
 474                 global $wgLegalTitleChars;
 475                 return $wgLegalTitleChars;
 476         }
 477
 478         /**
 479          * Returns a simple regex that will match on characters and sequences invalid in titles.
 480          * Note that this doesn't pick up many things that could be wrong with titles, but that
 481          * replacing this regex with something valid will make many titles valid.
 482          *
 483          * @return String regex string
 484          */
 485         static function getTitleInvalidRegex() {
 486                 static $rxTc = false;
 487                 if ( !$rxTc ) {
 488                         # Matching titles will be held as illegal.
 489                         $rxTc = '/' .
 490                                 # Any character not allowed is forbidden...
 491                                 '[^' . self::legalChars() . ']' .
 492                                 # URL percent encoding sequences interfere with the ability
 493                                 # to round-trip titles -- you can't link to them consistently.
 494                                 '|%[0-9A-Fa-f]{2}' .
 495                                 # XML/HTML character references produce similar issues.
 496                                 '|&[A-Za-z0-9\x80-\xff]+;' .
 497                                 '|&#[0-9]+;' .
 498                                 '|&#x[0-9A-Fa-f]+;' .
 499                                 '/S';
 500                 }
 501
 502                 return $rxTc;
 503         }
 504
 505         /**
 506          * Get a string representation of a title suitable for
 507          * including in a search index
 508          *
 509          * @param $ns Int a namespace index
 510          * @param $title String text-form main part
 511          * @return String a stripped-down title string ready for the search index
 512          */
 513         public static function indexTitle( $ns, $title ) {
 514                 global $wgContLang;
 515
 516                 $lc = SearchEngine::legalSearchChars() . '&#;';
 517                 $t = $wgContLang->normalizeForSearch( $title );
 518                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 519                 $t = $wgContLang->lc( $t );
 520
 521                 # Handle 's, s'
 522                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 523                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 524
 525                 $t = preg_replace( "/\\s+/", ' ', $t );
 526
 527                 if ( $ns == NS_FILE ) {
 528                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 529                 }
 530                 return trim( $t );
 531         }
 532
 533         /**
 534          * Make a prefixed DB key from a DB key and a namespace index
 535          *
 536          * @param $ns Int numerical representation of the namespace
 537          * @param $title String the DB key form the title
 538          * @param $fragment String The link fragment (after the "#")
 539          * @param $interwiki String The interwiki prefix
 540          * @return String the prefixed form of the title
 541          */
 542         public static function makeName( $ns, $title, $fragment = '', $interwiki = '' ) {
 543                 global $wgContLang;
 544
 545                 $namespace = $wgContLang->getNsText( $ns );
 546                 $name = $namespace == '' ? $title : "$namespace:$title";
 547                 if ( strval( $interwiki ) != '' ) {
 548                         $name = "$interwiki:$name";
 549                 }
 550                 if ( strval( $fragment ) != '' ) {
 551                         $name .= '#' . $fragment;
 552                 }
 553                 return $name;
 554         }
 555
 556         /**
 557          * Escape a text fragment, say from a link, for a URL
 558          *
 559          * @param $fragment string containing a URL or link fragment (after the "#")
 560          * @return String: escaped string
 561          */
 562         static function escapeFragmentForURL( $fragment ) {
 563                 # Note that we don't urlencode the fragment.  urlencoded Unicode
 564                 # fragments appear not to work in IE (at least up to 7) or in at least
 565                 # one version of Opera 9.x.  The W3C validator, for one, doesn't seem
 566                 # to care if they aren't encoded.
 567                 return Sanitizer::escapeId( $fragment, 'noninitial' );
 568         }
 569
 570         /**
 571          * Callback for usort() to do title sorts by (namespace, title)
 572          *
 573          * @param $a Title
 574          * @param $b Title
 575          *
 576          * @return Integer: result of string comparison, or namespace comparison
 577          */
 578         public static function compare( $a, $b ) {
 579                 if ( $a->getNamespace() == $b->getNamespace() ) {
 580                         return strcmp( $a->getText(), $b->getText() );
 581                 } else {
 582                         return $a->getNamespace() - $b->getNamespace();
 583                 }
 584         }
 585
 586         /**
 587          * Determine whether the object refers to a page within
 588          * this project.
 589          *
 590          * @return Bool TRUE if this is an in-project interwiki link or a wikilink, FALSE otherwise
 591          */
 592         public function isLocal() {
 593                 if ( $this->mInterwiki != '' ) {
 594                         return Interwiki::fetch( $this->mInterwiki )->isLocal();
 595                 } else {
 596                         return true;
 597                 }
 598         }
 599
 600         /**
 601          * Is this Title interwiki?
 602          *
 603          * @return Bool
 604          */
 605         public function isExternal() {
 606                 return ( $this->mInterwiki != '' );
 607         }
 608
 609         /**
 610          * Get the interwiki prefix (or null string)
 611          *
 612          * @return String Interwiki prefix
 613          */
 614         public function getInterwiki() {
 615                 return $this->mInterwiki;
 616         }
 617
 618         /**
 619          * Determine whether the object refers to a page within
 620          * this project and is transcludable.
 621          *
 622          * @return Bool TRUE if this is transcludable
 623          */
 624         public function isTrans() {
 625                 if ( $this->mInterwiki == '' ) {
 626                         return false;
 627                 }
 628
 629                 return Interwiki::fetch( $this->mInterwiki )->isTranscludable();
 630         }
 631
 632         /**
 633          * Returns the DB name of the distant wiki which owns the object.
 634          *
 635          * @return String the DB name
 636          */
 637         public function getTransWikiID() {
 638                 if ( $this->mInterwiki == '' ) {
 639                         return false;
 640                 }
 641
 642                 return Interwiki::fetch( $this->mInterwiki )->getWikiID();
 643         }
 644
 645         /**
 646          * Get the text form (spaces not underscores) of the main part
 647          *
 648          * @return String Main part of the title
 649          */
 650         public function getText() {
 651                 return $this->mTextform;
 652         }
 653
 654         /**
 655          * Get the URL-encoded form of the main part
 656          *
 657          * @return String Main part of the title, URL-encoded
 658          */
 659         public function getPartialURL() {
 660                 return $this->mUrlform;
 661         }
 662
 663         /**
 664          * Get the main part with underscores
 665          *
 666          * @return String: Main part of the title, with underscores
 667          */
 668         public function getDBkey() {
 669                 return $this->mDbkeyform;
 670         }
 671
 672         /**
 673          * Get the DB key with the initial letter case as specified by the user
 674          *
 675          * @return String DB key
 676          */
 677         function getUserCaseDBKey() {
 678                 return $this->mUserCaseDBKey;
 679         }
 680
 681         /**
 682          * Get the namespace index, i.e. one of the NS_xxxx constants.
 683          *
 684          * @return Integer: Namespace index
 685          */
 686         public function getNamespace() {
 687                 return $this->mNamespace;
 688         }
 689
 690         /**
 691          * Get the namespace text
 692          *
 693          * @return String: Namespace text
 694          */
 695         public function getNsText() {
 696                 global $wgContLang;
 697
 698                 if ( $this->mInterwiki != '' ) {
 699                         // This probably shouldn't even happen. ohh man, oh yuck.
 700                         // But for interwiki transclusion it sometimes does.
 701                         // Shit. Shit shit shit.
 702                         //
 703                         // Use the canonical namespaces if possible to try to
 704                         // resolve a foreign namespace.
 705                         if ( MWNamespace::exists( $this->mNamespace ) ) {
 706                                 return MWNamespace::getCanonicalName( $this->mNamespace );
 707                         }
 708                 }
 709
 710                 // Strip off subpages
 711                 $pagename = $this->getText();
 712                 if ( strpos( $pagename, '/' ) !== false ) {
 713                         list( $username , ) = explode( '/', $pagename, 2 );
 714                 } else {
 715                         $username = $pagename;
 716                 }
 717
 718                 if ( $wgContLang->needsGenderDistinction() &&
 719                                 MWNamespace::hasGenderDistinction( $this->mNamespace ) ) {
 720                         $gender = GenderCache::singleton()->getGenderOf( $username, __METHOD__ );
 721                         return $wgContLang->getGenderNsText( $this->mNamespace, $gender );
 722                 }
 723
 724                 return $wgContLang->getNsText( $this->mNamespace );
 725         }
 726
 727         /**
 728          * Get the namespace text of the subject (rather than talk) page
 729          *
 730          * @return String Namespace text
 731          */
 732         public function getSubjectNsText() {
 733                 global $wgContLang;
 734                 return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
 735         }
 736
 737         /**
 738          * Get the namespace text of the talk page
 739          *
 740          * @return String Namespace text
 741          */
 742         public function getTalkNsText() {
 743                 global $wgContLang;
 744                 return( $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) ) );
 745         }
 746
 747         /**
 748          * Could this title have a corresponding talk page?
 749          *
 750          * @return Bool TRUE or FALSE
 751          */
 752         public function canTalk() {
 753                 return( MWNamespace::canTalk( $this->mNamespace ) );
 754         }
 755
 756         /**
 757          * Is this in a namespace that allows actual pages?
 758          *
 759          * @return Bool
 760          * @internal note -- uses hardcoded namespace index instead of constants
 761          */
 762         public function canExist() {
 763                 return $this->mNamespace >= NS_MAIN;
 764         }
 765
 766         /**
 767          * Can this title be added to a user's watchlist?
 768          *
 769          * @return Bool TRUE or FALSE
 770          */
 771         public function isWatchable() {
 772                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
 773         }
 774
 775         /**
 776          * Returns true if this is a special page.
 777          *
 778          * @return boolean
 779          */
 780         public function isSpecialPage() {
 781                 return $this->getNamespace() == NS_SPECIAL;
 782         }
 783
 784         /**
 785          * Returns true if this title resolves to the named special page
 786          *
 787          * @param $name String The special page name
 788          * @return boolean
 789          */
 790         public function isSpecial( $name ) {
 791                 if ( $this->isSpecialPage() ) {
 792                         list( $thisName, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $this->getDBkey() );
 793                         if ( $name == $thisName ) {
 794                                 return true;
 795                         }
 796                 }
 797                 return false;
 798         }
 799
 800         /**
 801          * If the Title refers to a special page alias which is not the local default, resolve
 802          * the alias, and localise the name as necessary.  Otherwise, return $this
 803          *
 804          * @return Title
 805          */
 806         public function fixSpecialName() {
 807                 if ( $this->isSpecialPage() ) {
 808                         list( $canonicalName, $par ) = SpecialPageFactory::resolveAlias( $this->mDbkeyform );
 809                         if ( $canonicalName ) {
 810                                 $localName = SpecialPageFactory::getLocalNameFor( $canonicalName, $par );
 811                                 if ( $localName != $this->mDbkeyform ) {
 812                                         return Title::makeTitle( NS_SPECIAL, $localName );
 813                                 }
 814                         }
 815                 }
 816                 return $this;
 817         }
 818
 819         /**
 820          * Returns true if the title is inside the specified namespace.
 821          *
 822          * Please make use of this instead of comparing to getNamespace()
 823          * This function is much more resistant to changes we may make
 824          * to namespaces than code that makes direct comparisons.
 825          * @param $ns int The namespace
 826          * @return bool
 827          * @since 1.19
 828          */
 829         public function inNamespace( $ns ) {
 830                 return MWNamespace::equals( $this->getNamespace(), $ns );
 831         }
 832
 833         /**
 834          * Returns true if the title is inside one of the specified namespaces.
 835          *
 836          * @param ...$namespaces The namespaces to check for
 837          * @return bool
 838          * @since 1.19
 839          */
 840         public function inNamespaces( /* ... */ ) {
 841                 $namespaces = func_get_args();
 842                 if ( count( $namespaces ) > 0 && is_array( $namespaces[0] ) ) {
 843                         $namespaces = $namespaces[0];
 844                 }
 845
 846                 foreach ( $namespaces as $ns ) {
 847                         if ( $this->inNamespace( $ns ) ) {
 848                                 return true;
 849                         }
 850                 }
 851
 852                 return false;
 853         }
 854
 855         /**
 856          * Returns true if the title has the same subject namespace as the
 857          * namespace specified.
 858          * For example this method will take NS_USER and return true if namespace
 859          * is either NS_USER or NS_USER_TALK since both of them have NS_USER
 860          * as their subject namespace.
 861          *
 862          * This is MUCH simpler than individually testing for equivilance
 863          * against both NS_USER and NS_USER_TALK, and is also forward compatible.
 864          * @since 1.19
 865          * @return bool
 866          */
 867         public function hasSubjectNamespace( $ns ) {
 868                 return MWNamespace::subjectEquals( $this->getNamespace(), $ns );
 869         }
 870
 871         /**
 872          * Is this Title in a namespace which contains content?
 873          * In other words, is this a content page, for the purposes of calculating
 874          * statistics, etc?
 875          *
 876          * @return Boolean
 877          */
 878         public function isContentPage() {
 879                 return MWNamespace::isContent( $this->getNamespace() );
 880         }
 881
 882         /**
 883          * Would anybody with sufficient privileges be able to move this page?
 884          * Some pages just aren't movable.
 885          *
 886          * @return Bool TRUE or FALSE
 887          */
 888         public function isMovable() {
 889                 if ( !MWNamespace::isMovable( $this->getNamespace() ) || $this->getInterwiki() != '' ) {
 890                         // Interwiki title or immovable namespace. Hooks don't get to override here
 891                         return false;
 892                 }
 893
 894                 $result = true;
 895                 wfRunHooks( 'TitleIsMovable', array( $this, &$result ) );
 896                 return $result;
 897         }
 898
 899         /**
 900          * Is this the mainpage?
 901          * @note Title::newFromText seams to be sufficiently optimized by the title
 902          * cache that we don't need to over-optimize by doing direct comparisons and
 903          * acidentally creating new bugs where $title->equals( Title::newFromText() )
 904          * ends up reporting something differently than $title->isMainPage();
 905          *
 906          * @since 1.18
 907          * @return Bool
 908          */
 909         public function isMainPage() {
 910                 return $this->equals( Title::newMainPage() );
 911         }
 912
 913         /**
 914          * Is this a subpage?
 915          *
 916          * @return Bool
 917          */
 918         public function isSubpage() {
 919                 return MWNamespace::hasSubpages( $this->mNamespace )
 920                         ? strpos( $this->getText(), '/' ) !== false
 921                         : false;
 922         }
 923
 924         /**
 925          * Is this a conversion table for the LanguageConverter?
 926          *
 927          * @return Bool
 928          */
 929         public function isConversionTable() {
 930                 return $this->getNamespace() == NS_MEDIAWIKI &&
 931                         strpos( $this->getText(), 'Conversiontable' ) !== false;
 932         }
 933
 934         /**
 935          * Does that page contain wikitext, or it is JS, CSS or whatever?
 936          *
 937          * @return Bool
 938          */
 939         public function isWikitextPage() {
 940                 $retval = !$this->isCssOrJsPage() && !$this->isCssJsSubpage();
 941                 wfRunHooks( 'TitleIsWikitextPage', array( $this, &$retval ) );
 942                 return $retval;
 943         }
 944
 945         /**
 946          * Could this page contain custom CSS or JavaScript, based
 947          * on the title?
 948          *
 949          * @return Bool
 950          */
 951         public function isCssOrJsPage() {
 952                 $retval = $this->mNamespace == NS_MEDIAWIKI
 953                         && preg_match( '!\.(?:css|js)$!u', $this->mTextform ) > 0;
 954                 wfRunHooks( 'TitleIsCssOrJsPage', array( $this, &$retval ) );
 955                 return $retval;
 956         }
 957
 958         /**
 959          * Is this a .css or .js subpage of a user page?
 960          * @return Bool
 961          */
 962         public function isCssJsSubpage() {
 963                 return ( NS_USER == $this->mNamespace and preg_match( "/\\/.*\\.(?:css|js)$/", $this->mTextform ) );
 964         }
 965
 966         /**
 967          * Trim down a .css or .js subpage title to get the corresponding skin name
 968          *
 969          * @return string containing skin name from .css or .js subpage title
 970          */
 971         public function getSkinFromCssJsSubpage() {
 972                 $subpage = explode( '/', $this->mTextform );
 973                 $subpage = $subpage[ count( $subpage ) - 1 ];
 974                 $lastdot = strrpos( $subpage, '.' );
 975                 if ( $lastdot === false )
 976                         return $subpage; # Never happens: only called for names ending in '.css' or '.js'
 977                 return substr( $subpage, 0, $lastdot );
 978         }
 979
 980         /**
 981          * Is this a .css subpage of a user page?
 982          *
 983          * @return Bool
 984          */
 985         public function isCssSubpage() {
 986                 return ( NS_USER == $this->mNamespace && preg_match( "/\\/.*\\.css$/", $this->mTextform ) );
 987         }
 988
 989         /**
 990          * Is this a .js subpage of a user page?
 991          *
 992          * @return Bool
 993          */
 994         public function isJsSubpage() {
 995                 return ( NS_USER == $this->mNamespace && preg_match( "/\\/.*\\.js$/", $this->mTextform ) );
 996         }
 997
 998         /**
 999          * Is this a talk page of some sort?
1000          *
1001          * @return Bool
1002          */
1003         public function isTalkPage() {
1004                 return MWNamespace::isTalk( $this->getNamespace() );
1005         }
1006
1007         /**
1008          * Get a Title object associated with the talk page of this article
1009          *
1010          * @return Title the object for the talk page
1011          */
1012         public function getTalkPage() {
1013                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1014         }
1015
1016         /**
1017          * Get a title object associated with the subject page of this
1018          * talk page
1019          *
1020          * @return Title the object for the subject page
1021          */
1022         public function getSubjectPage() {
1023                 // Is this the same title?
1024                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
1025                 if ( $this->getNamespace() == $subjectNS ) {
1026                         return $this;
1027                 }
1028                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
1029         }
1030
1031         /**
1032          * Get the default namespace index, for when there is no namespace
1033          *
1034          * @return Int Default namespace index
1035          */
1036         public function getDefaultNamespace() {
1037                 return $this->mDefaultNamespace;
1038         }
1039
1040         /**
1041          * Get title for search index
1042          *
1043          * @return String a stripped-down title string ready for the
1044          *  search index
1045          */
1046         public function getIndexTitle() {
1047                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
1048         }
1049
1050         /**
1051          * Get the Title fragment (i.e.\ the bit after the #) in text form
1052          *
1053          * @return String Title fragment
1054          */
1055         public function getFragment() {
1056                 return $this->mFragment;
1057         }
1058
1059         /**
1060          * Get the fragment in URL form, including the "#" character if there is one
1061          * @return String Fragment in URL form
1062          */
1063         public function getFragmentForURL() {
1064                 if ( $this->mFragment == '' ) {
1065                         return '';
1066                 } else {
1067                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
1068                 }
1069         }
1070
1071         /**
1072          * Set the fragment for this title. Removes the first character from the
1073          * specified fragment before setting, so it assumes you're passing it with
1074          * an initial "#".
1075          *
1076          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
1077          * Still in active use privately.
1078          *
1079          * @param $fragment String text
1080          */
1081         public function setFragment( $fragment ) {
1082                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
1083         }
1084
1085         /**
1086          * Prefix some arbitrary text with the namespace or interwiki prefix
1087          * of this object
1088          *
1089          * @param $name String the text
1090          * @return String the prefixed text
1091          * @private
1092          */
1093         private function prefix( $name ) {
1094                 $p = '';
1095                 if ( $this->mInterwiki != '' ) {
1096                         $p = $this->mInterwiki . ':';
1097                 }
1098
1099                 if ( 0 != $this->mNamespace ) {
1100                         $p .= $this->getNsText() . ':';
1101                 }
1102                 return $p . $name;
1103         }
1104
1105         /**
1106          * Get the prefixed database key form
1107          *
1108          * @return String the prefixed title, with underscores and
1109          *  any interwiki and namespace prefixes
1110          */
1111         public function getPrefixedDBkey() {
1112                 $s = $this->prefix( $this->mDbkeyform );
1113                 $s = str_replace( ' ', '_', $s );
1114                 return $s;
1115         }
1116
1117         /**
1118          * Get the prefixed title with spaces.
1119          * This is the form usually used for display
1120          *
1121          * @return String the prefixed title, with spaces
1122          */
1123         public function getPrefixedText() {
1124                 // @todo FIXME: Bad usage of empty() ?
1125                 if ( empty( $this->mPrefixedText ) ) {
1126                         $s = $this->prefix( $this->mTextform );
1127                         $s = str_replace( '_', ' ', $s );
1128                         $this->mPrefixedText = $s;
1129                 }
1130                 return $this->mPrefixedText;
1131         }
1132
1133         /**
1134          * Return a string representation of this title
1135          *
1136          * @return String representation of this title
1137          */
1138         public function __toString() {
1139                 return $this->getPrefixedText();
1140         }
1141
1142         /**
1143          * Get the prefixed title with spaces, plus any fragment
1144          * (part beginning with '#')
1145          *
1146          * @return String the prefixed title, with spaces and the fragment, including '#'
1147          */
1148         public function getFullText() {
1149                 $text = $this->getPrefixedText();
1150                 if ( $this->mFragment != '' ) {
1151                         $text .= '#' . $this->mFragment;
1152                 }
1153                 return $text;
1154         }
1155
1156         /**
1157          * Get the base page name, i.e. the leftmost part before any slashes
1158          *
1159          * @return String Base name
1160          */
1161         public function getBaseText() {
1162                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1163                         return $this->getText();
1164                 }
1165
1166                 $parts = explode( '/', $this->getText() );
1167                 # Don't discard the real title if there's no subpage involved
1168                 if ( count( $parts ) > 1 ) {
1169                         unset( $parts[count( $parts ) - 1] );
1170                 }
1171                 return implode( '/', $parts );
1172         }
1173
1174         /**
1175          * Get the lowest-level subpage name, i.e. the rightmost part after any slashes
1176          *
1177          * @return String Subpage name
1178          */
1179         public function getSubpageText() {
1180                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1181                         return( $this->mTextform );
1182                 }
1183                 $parts = explode( '/', $this->mTextform );
1184                 return( $parts[count( $parts ) - 1] );
1185         }
1186
1187         /**
1188          * Get the HTML-escaped displayable text form.
1189          * Used for the title field in <a> tags.
1190          *
1191          * @return String the text, including any prefixes
1192          */
1193         public function getEscapedText() {
1194                 wfDeprecated( __METHOD__, '1.19' );
1195                 return htmlspecialchars( $this->getPrefixedText() );
1196         }
1197
1198         /**
1199          * Get a URL-encoded form of the subpage text
1200          *
1201          * @return String URL-encoded subpage name
1202          */
1203         public function getSubpageUrlForm() {
1204                 $text = $this->getSubpageText();
1205                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
1206                 return( $text );
1207         }
1208
1209         /**
1210          * Get a URL-encoded title (not an actual URL) including interwiki
1211          *
1212          * @return String the URL-encoded form
1213          */
1214         public function getPrefixedURL() {
1215                 $s = $this->prefix( $this->mDbkeyform );
1216                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
1217                 return $s;
1218         }
1219
1220         /**
1221          * Helper to fix up the get{Local,Full,Link,Canonical}URL args
1222          * get{Canonical,Full,Link,Local}URL methods accepted an optional
1223          * second argument named variant. This was deprecated in favor
1224          * of passing an array of option with a "variant" key
1225          * Once $query2 is removed for good, this helper can be dropped
1226          * andthe wfArrayToCGI moved to getLocalURL();
1227          *
1228          * @since 1.19 (r105919)
1229          * @return String
1230          */
1231         private static function fixUrlQueryArgs( $query, $query2 = false ) {
1232                 if( $query2 !== false ) {
1233                         wfDeprecated( "Title::get{Canonical,Full,Link,Local} method called with a second parameter is deprecated. Add your parameter to an array passed as the first parameter.", "1.19" );
1234                 }
1235                 if ( is_array( $query ) ) {
1236                         $query = wfArrayToCGI( $query );
1237                 }
1238                 if ( $query2 ) {
1239                         if ( is_string( $query2 ) ) {
1240                                 // $query2 is a string, we will consider this to be
1241                                 // a deprecated $variant argument and add it to the query
1242                                 $query2 = wfArrayToCGI( array( 'variant' => $query2 ) );
1243                         } else {
1244                                 $query2 = wfArrayToCGI( $query2 );
1245                         }
1246                         // If we have $query content add a & to it first
1247                         if ( $query ) {
1248                                 $query .= '&';
1249                         }
1250                         // Now append the queries together
1251                         $query .= $query2;
1252                 }
1253                 return $query;
1254         }
1255
1256         /**
1257          * Get a real URL referring to this title, with interwiki link and
1258          * fragment
1259          *
1260          * See getLocalURL for the arguments.
1261          *
1262          * @see self::getLocalURL
1263          * @return String the URL
1264          */
1265         public function getFullURL( $query = '', $query2 = false ) {
1266                 $query = self::fixUrlQueryArgs( $query, $query2 );
1267
1268                 # Hand off all the decisions on urls to getLocalURL
1269                 $url = $this->getLocalURL( $query );
1270
1271                 # Expand the url to make it a full url. Note that getLocalURL has the
1272                 # potential to output full urls for a variety of reasons, so we use
1273                 # wfExpandUrl instead of simply prepending $wgServer
1274                 $url = wfExpandUrl( $url, PROTO_RELATIVE );
1275
1276                 # Finally, add the fragment.
1277                 $url .= $this->getFragmentForURL();
1278
1279                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
1280                 return $url;
1281         }
1282
1283         /**
1284          * Get a URL with no fragment or server name.  If this page is generated
1285          * with action=render, $wgServer is prepended.
1286          *
1287
1288          * @param $query string|array an optional query string,
1289          *   not used for interwiki     links. Can be specified as an associative array as well,
1290          *   e.g., array( 'action' => 'edit' ) (keys and values will be URL-escaped).
1291          *   Some query patterns will trigger various shorturl path replacements.
1292          * @param $query2 Mixed: An optional secondary query array. This one MUST
1293          *   be an array. If a string is passed it will be interpreted as a deprecated
1294          *   variant argument and urlencoded into a variant= argument.
1295          *   This second query argument will be added to the $query
1296          *   The second parameter is deprecated since 1.19. Pass it as a key,value
1297          *   pair in the first parameter array instead.
1298          *
1299          * @return String the URL
1300          */
1301         public function getLocalURL( $query = '', $query2 = false ) {
1302                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
1303
1304                 $query = self::fixUrlQueryArgs( $query, $query2 );
1305
1306                 $interwiki = Interwiki::fetch( $this->mInterwiki );
1307                 if ( $interwiki ) {
1308                         $namespace = $this->getNsText();
1309                         if ( $namespace != '' ) {
1310                                 # Can this actually happen? Interwikis shouldn't be parsed.
1311                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
1312                                 $namespace .= ':';
1313                         }
1314                         $url = $interwiki->getURL( $namespace . $this->getDBkey() );
1315                         $url = wfAppendQuery( $url, $query );
1316                 } else {
1317                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
1318                         if ( $query == '' ) {
1319                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
1320                                 wfRunHooks( 'GetLocalURL::Article', array( &$this, &$url ) );
1321                         } else {
1322                                 global $wgVariantArticlePath, $wgActionPaths;
1323                                 $url = false;
1324                                 $matches = array();
1325
1326                                 if ( !empty( $wgActionPaths ) &&
1327                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
1328                                 {
1329                                         $action = urldecode( $matches[2] );
1330                                         if ( isset( $wgActionPaths[$action] ) ) {
1331                                                 $query = $matches[1];
1332                                                 if ( isset( $matches[4] ) ) {
1333                                                         $query .= $matches[4];
1334                                                 }
1335                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
1336                                                 if ( $query != '' ) {
1337                                                         $url = wfAppendQuery( $url, $query );
1338                                                 }
1339                                         }
1340                                 }
1341
1342                                 if ( $url === false &&
1343                                         $wgVariantArticlePath &&
1344                                         $this->getPageLanguage()->hasVariants() &&
1345                                         preg_match( '/^variant=([^&]*)$/', $query, $matches ) )
1346                                 {
1347                                         $variant = urldecode( $matches[1] );
1348                                         if ( $this->getPageLanguage()->hasVariant( $variant ) ) {
1349                                                 // Only do the variant replacement if the given variant is a valid
1350                                                 // variant for the page's language.
1351                                                 $url = str_replace( '$2', urlencode( $variant ), $wgVariantArticlePath );
1352                                                 $url = str_replace( '$1', $dbkey, $url );
1353                                         }
1354                                 }
1355
1356                                 if ( $url === false ) {
1357                                         if ( $query == '-' ) {
1358                                                 $query = '';
1359                                         }
1360                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
1361                                 }
1362                         }
1363
1364                         wfRunHooks( 'GetLocalURL::Internal', array( &$this, &$url, $query ) );
1365
1366                         // @todo FIXME: This causes breakage in various places when we
1367                         // actually expected a local URL and end up with dupe prefixes.
1368                         if ( $wgRequest->getVal( 'action' ) == 'render' ) {
1369                                 $url = $wgServer . $url;
1370                         }
1371                 }
1372                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
1373                 return $url;
1374         }
1375
1376         /**
1377          * Get a URL that's the simplest URL that will be valid to link, locally,
1378          * to the current Title.  It includes the fragment, but does not include
1379          * the server unless action=render is used (or the link is external).  If
1380          * there's a fragment but the prefixed text is empty, we just return a link
1381          * to the fragment.
1382          *
1383          * The result obviously should not be URL-escaped, but does need to be
1384          * HTML-escaped if it's being output in HTML.
1385          *
1386          * See getLocalURL for the arguments.
1387          *
1388          * @see self::getLocalURL
1389          * @return String the URL
1390          */
1391         public function getLinkURL( $query = '', $query2 = false ) {
1392                 wfProfileIn( __METHOD__ );
1393                 if ( $this->isExternal() ) {
1394                         $ret = $this->getFullURL( $query, $query2 );
1395                 } elseif ( $this->getPrefixedText() === '' && $this->getFragment() !== '' ) {
1396                         $ret = $this->getFragmentForURL();
1397                 } else {
1398                         $ret = $this->getLocalURL( $query, $query2 ) . $this->getFragmentForURL();
1399                 }
1400                 wfProfileOut( __METHOD__ );
1401                 return $ret;
1402         }
1403
1404         /**
1405          * Get an HTML-escaped version of the URL form, suitable for
1406          * using in a link, without a server name or fragment
1407          *
1408          * See getLocalURL for the arguments.
1409          *
1410          * @see self::getLocalURL
1411          * @return String the URL
1412          */
1413         public function escapeLocalURL( $query = '', $query2 = false ) {
1414                 wfDeprecated( __METHOD__, '1.19' );
1415                 return htmlspecialchars( $this->getLocalURL( $query, $query2 ) );
1416         }
1417
1418         /**
1419          * Get an HTML-escaped version of the URL form, suitable for
1420          * using in a link, including the server name and fragment
1421          *
1422          * See getLocalURL for the arguments.
1423          *
1424          * @see self::getLocalURL
1425          * @return String the URL
1426          */
1427         public function escapeFullURL( $query = '', $query2 = false ) {
1428                 wfDeprecated( __METHOD__, '1.19' );
1429                 return htmlspecialchars( $this->getFullURL( $query, $query2 ) );
1430         }
1431
1432         /**
1433          * Get the URL form for an internal link.
1434          * - Used in various Squid-related code, in case we have a different
1435          * internal hostname for the server from the exposed one.
1436          *
1437          * This uses $wgInternalServer to qualify the path, or $wgServer
1438          * if $wgInternalServer is not set. If the server variable used is
1439          * protocol-relative, the URL will be expanded to http://
1440          *
1441          * See getLocalURL for the arguments.
1442          *
1443          * @see self::getLocalURL
1444          * @return String the URL
1445          */
1446         public function getInternalURL( $query = '', $query2 = false ) {
1447                 global $wgInternalServer, $wgServer;
1448                 $query = self::fixUrlQueryArgs( $query, $query2 );
1449                 $server = $wgInternalServer !== false ? $wgInternalServer : $wgServer;
1450                 $url = wfExpandUrl( $server . $this->getLocalURL( $query ), PROTO_HTTP );
1451                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
1452                 return $url;
1453         }
1454
1455         /**
1456          * Get the URL for a canonical link, for use in things like IRC and
1457          * e-mail notifications. Uses $wgCanonicalServer and the
1458          * GetCanonicalURL hook.
1459          *
1460          * NOTE: Unlike getInternalURL(), the canonical URL includes the fragment
1461          *
1462          * See getLocalURL for the arguments.
1463          *
1464          * @see self::getLocalURL
1465          * @return string The URL
1466          * @since 1.18
1467          */
1468         public function getCanonicalURL( $query = '', $query2 = false ) {
1469                 $query = self::fixUrlQueryArgs( $query, $query2 );
1470                 $url = wfExpandUrl( $this->getLocalURL( $query ) . $this->getFragmentForURL(), PROTO_CANONICAL );
1471                 wfRunHooks( 'GetCanonicalURL', array( &$this, &$url, $query ) );
1472                 return $url;
1473         }
1474
1475         /**
1476          * HTML-escaped version of getCanonicalURL()
1477          *
1478          * See getLocalURL for the arguments.
1479          *
1480          * @see self::getLocalURL
1481          * @since 1.18
1482          * @return string
1483          */
1484         public function escapeCanonicalURL( $query = '', $query2 = false ) {
1485                 wfDeprecated( __METHOD__, '1.19' );
1486                 return htmlspecialchars( $this->getCanonicalURL( $query, $query2 ) );
1487         }
1488
1489         /**
1490          * Get the edit URL for this Title
1491          *
1492          * @return String the URL, or a null string if this is an
1493          *  interwiki link
1494          */
1495         public function getEditURL() {
1496                 if ( $this->mInterwiki != '' ) {
1497                         return '';
1498                 }
1499                 $s = $this->getLocalURL( 'action=edit' );
1500
1501                 return $s;
1502         }
1503
1504         /**
1505          * Is $wgUser watching this page?
1506          *
1507          * @return Bool
1508          */
1509         public function userIsWatching() {
1510                 global $wgUser;
1511
1512                 if ( is_null( $this->mWatched ) ) {
1513                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn() ) {
1514                                 $this->mWatched = false;
1515                         } else {
1516                                 $this->mWatched = $wgUser->isWatched( $this );
1517                         }
1518                 }
1519                 return $this->mWatched;
1520         }
1521
1522         /**
1523          * Can $wgUser read this page?
1524          *
1525          * @deprecated in 1.19; use userCan(), quickUserCan() or getUserPermissionsErrors() instead
1526          * @return Bool
1527          * @todo fold these checks into userCan()
1528          */
1529         public function userCanRead() {
1530                 wfDeprecated( __METHOD__, '1.19' );
1531                 return $this->userCan( 'read' );
1532         }
1533
1534         /**
1535          * Can $user perform $action on this page?
1536          * This skips potentially expensive cascading permission checks
1537          * as well as avoids expensive error formatting
1538          *
1539          * Suitable for use for nonessential UI controls in common cases, but
1540          * _not_ for functional access control.
1541          *
1542          * May provide false positives, but should never provide a false negative.
1543          *
1544          * @param $action String action that permission needs to be checked for
1545          * @param $user User to check (since 1.19); $wgUser will be used if not
1546          *              provided.
1547          * @return Bool
1548          */
1549         public function quickUserCan( $action, $user = null ) {
1550                 return $this->userCan( $action, $user, false );
1551         }
1552
1553         /**
1554          * Can $user perform $action on this page?
1555          *
1556          * @param $action String action that permission needs to be checked for
1557          * @param $user User to check (since 1.19); $wgUser will be used if not
1558          *   provided.
1559          * @param $doExpensiveQueries Bool Set this to false to avoid doing
1560          *   unnecessary queries.
1561          * @return Bool
1562          */
1563         public function userCan( $action, $user = null, $doExpensiveQueries = true ) {
1564                 if ( !$user instanceof User ) {
1565                         global $wgUser;
1566                         $user = $wgUser;
1567                 }
1568                 return !count( $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries, true ) );
1569         }
1570
1571         /**
1572          * Can $user perform $action on this page?
1573          *
1574          * @todo FIXME: This *does not* check throttles (User::pingLimiter()).
1575          *
1576          * @param $action String action that permission needs to be checked for
1577          * @param $user User to check
1578          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary
1579          *   queries by skipping checks for cascading protections and user blocks.
1580          * @param $ignoreErrors Array of Strings Set this to a list of message keys
1581          *   whose corresponding errors may be ignored.
1582          * @return Array of arguments to wfMsg to explain permissions problems.
1583          */
1584         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1585                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1586
1587                 // Remove the errors being ignored.
1588                 foreach ( $errors as $index => $error ) {
1589                         $error_key = is_array( $error ) ? $error[0] : $error;
1590
1591                         if ( in_array( $error_key, $ignoreErrors ) ) {
1592                                 unset( $errors[$index] );
1593                         }
1594                 }
1595
1596                 return $errors;
1597         }
1598
1599         /**
1600          * Permissions checks that fail most often, and which are easiest to test.
1601          *
1602          * @param $action String the action to check
1603          * @param $user User user to check
1604          * @param $errors Array list of current errors
1605          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1606          * @param $short Boolean short circuit on first error
1607          *
1608          * @return Array list of errors
1609          */
1610         private function checkQuickPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1611                 if ( $action == 'create' ) {
1612                         if ( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1613                                  ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1614                                 $errors[] = $user->isAnon() ? array( 'nocreatetext' ) : array( 'nocreate-loggedin' );
1615                         }
1616                 } elseif ( $action == 'move' ) {
1617                         if ( !$user->isAllowed( 'move-rootuserpages' )
1618                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1619                                 // Show user page-specific message only if the user can move other pages
1620                                 $errors[] = array( 'cant-move-user-page' );
1621                         }
1622
1623                         // Check if user is allowed to move files if it's a file
1624                         if ( $this->mNamespace == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1625                                 $errors[] = array( 'movenotallowedfile' );
1626                         }
1627
1628                         if ( !$user->isAllowed( 'move' ) ) {
1629                                 // User can't move anything
1630                                 global $wgGroupPermissions;
1631                                 $userCanMove = false;
1632                                 if ( isset( $wgGroupPermissions['user']['move'] ) ) {
1633                                         $userCanMove = $wgGroupPermissions['user']['move'];
1634                                 }
1635                                 $autoconfirmedCanMove = false;
1636                                 if ( isset( $wgGroupPermissions['autoconfirmed']['move'] ) ) {
1637                                         $autoconfirmedCanMove = $wgGroupPermissions['autoconfirmed']['move'];
1638                                 }
1639                                 if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
1640                                         // custom message if logged-in users without any special rights can move
1641                                         $errors[] = array( 'movenologintext' );
1642                                 } else {
1643                                         $errors[] = array( 'movenotallowed' );
1644                                 }
1645                         }
1646                 } elseif ( $action == 'move-target' ) {
1647                         if ( !$user->isAllowed( 'move' ) ) {
1648                                 // User can't move anything
1649                                 $errors[] = array( 'movenotallowed' );
1650                         } elseif ( !$user->isAllowed( 'move-rootuserpages' )
1651                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1652                                 // Show user page-specific message only if the user can move other pages
1653                                 $errors[] = array( 'cant-move-to-user-page' );
1654                         }
1655                 } elseif ( !$user->isAllowed( $action ) ) {
1656                         $errors[] = $this->missingPermissionError( $action, $short );
1657                 }
1658
1659                 return $errors;
1660         }
1661
1662         /**
1663          * Add the resulting error code to the errors array
1664          *
1665          * @param $errors Array list of current errors
1666          * @param $result Mixed result of errors
1667          *
1668          * @return Array list of errors
1669          */
1670         private function resultToError( $errors, $result ) {
1671                 if ( is_array( $result ) && count( $result ) && !is_array( $result[0] ) ) {
1672                         // A single array representing an error
1673                         $errors[] = $result;
1674                 } elseif ( is_array( $result ) && is_array( $result[0] ) ) {
1675                         // A nested array representing multiple errors
1676                         $errors = array_merge( $errors, $result );
1677                 } elseif ( $result !== '' && is_string( $result ) ) {
1678                         // A string representing a message-id
1679                         $errors[] = array( $result );
1680                 } elseif ( $result === false ) {
1681                         // a generic "We don't want them to do that"
1682                         $errors[] = array( 'badaccess-group0' );
1683                 }
1684                 return $errors;
1685         }
1686
1687         /**
1688          * Check various permission hooks
1689          *
1690          * @param $action String the action to check
1691          * @param $user User user to check
1692          * @param $errors Array list of current errors
1693          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1694          * @param $short Boolean short circuit on first error
1695          *
1696          * @return Array list of errors
1697          */
1698         private function checkPermissionHooks( $action, $user, $errors, $doExpensiveQueries, $short ) {
1699                 // Use getUserPermissionsErrors instead
1700                 $result = '';
1701                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1702                         return $result ? array() : array( array( 'badaccess-group0' ) );
1703                 }
1704                 // Check getUserPermissionsErrors hook
1705                 if ( !wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1706                         $errors = $this->resultToError( $errors, $result );
1707                 }
1708                 // Check getUserPermissionsErrorsExpensive hook
1709                 if ( $doExpensiveQueries && !( $short && count( $errors ) > 0 ) &&
1710                          !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) ) ) {
1711                         $errors = $this->resultToError( $errors, $result );
1712                 }
1713
1714                 return $errors;
1715         }
1716
1717         /**
1718          * Check permissions on special pages & namespaces
1719          *
1720          * @param $action String the action to check
1721          * @param $user User user to check
1722          * @param $errors Array list of current errors
1723          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1724          * @param $short Boolean short circuit on first error
1725          *
1726          * @return Array list of errors
1727          */
1728         private function checkSpecialsAndNSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1729                 # Only 'createaccount' and 'execute' can be performed on
1730                 # special pages, which don't actually exist in the DB.
1731                 $specialOKActions = array( 'createaccount', 'execute', 'read' );
1732                 if ( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions ) ) {
1733                         $errors[] = array( 'ns-specialprotected' );
1734                 }
1735
1736                 # Check $wgNamespaceProtection for restricted namespaces
1737                 if ( $this->isNamespaceProtected( $user ) ) {
1738                         $ns = $this->mNamespace == NS_MAIN ?
1739                                 wfMsg( 'nstab-main' ) : $this->getNsText();
1740                         $errors[] = $this->mNamespace == NS_MEDIAWIKI ?
1741                                 array( 'protectedinterface' ) : array( 'namespaceprotected',  $ns );
1742                 }
1743
1744                 return $errors;
1745         }
1746
1747         /**
1748          * Check CSS/JS sub-page permissions
1749          *
1750          * @param $action String the action to check
1751          * @param $user User user to check
1752          * @param $errors Array list of current errors
1753          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1754          * @param $short Boolean short circuit on first error
1755          *
1756          * @return Array list of errors
1757          */
1758         private function checkCSSandJSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1759                 # Protect css/js subpages of user pages
1760                 # XXX: this might be better using restrictions
1761                 # XXX: right 'editusercssjs' is deprecated, for backward compatibility only
1762                 if ( $action != 'patrol' && !$user->isAllowed( 'editusercssjs' )
1763                                 && !preg_match( '/^' . preg_quote( $user->getName(), '/' ) . '\//', $this->mTextform ) ) {
1764                         if ( $this->isCssSubpage() && !$user->isAllowed( 'editusercss' ) ) {
1765                                 $errors[] = array( 'customcssprotected' );
1766                         } elseif ( $this->isJsSubpage() && !$user->isAllowed( 'edituserjs' ) ) {
1767                                 $errors[] = array( 'customjsprotected' );
1768                         }
1769                 }
1770
1771                 return $errors;
1772         }
1773
1774         /**
1775          * Check against page_restrictions table requirements on this
1776          * page. The user must possess all required rights for this
1777          * action.
1778          *
1779          * @param $action String the action to check
1780          * @param $user User user to check
1781          * @param $errors Array list of current errors
1782          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1783          * @param $short Boolean short circuit on first error
1784          *
1785          * @return Array list of errors
1786          */
1787         private function checkPageRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1788                 foreach ( $this->getRestrictions( $action ) as $right ) {
1789                         // Backwards compatibility, rewrite sysop -> protect
1790                         if ( $right == 'sysop' ) {
1791                                 $right = 'protect';
1792                         }
1793                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1794                                 // Users with 'editprotected' permission can edit protected pages
1795                                 // without cascading option turned on.
1796                                 if ( $action != 'edit' || !$user->isAllowed( 'editprotected' )
1797                                         || $this->mCascadeRestriction )
1798                                 {
1799                                         $errors[] = array( 'protectedpagetext', $right );
1800                                 }
1801                         }
1802                 }
1803
1804                 return $errors;
1805         }
1806
1807         /**
1808          * Check restrictions on cascading pages.
1809          *
1810          * @param $action String the action to check
1811          * @param $user User to check
1812          * @param $errors Array list of current errors
1813          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1814          * @param $short Boolean short circuit on first error
1815          *
1816          * @return Array list of errors
1817          */
1818         private function checkCascadingSourcesRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1819                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1820                         # We /could/ use the protection level on the source page, but it's
1821                         # fairly ugly as we have to establish a precedence hierarchy for pages
1822                         # included by multiple cascade-protected pages. So just restrict
1823                         # it to people with 'protect' permission, as they could remove the
1824                         # protection anyway.
1825                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1826                         # Cascading protection depends on more than this page...
1827                         # Several cascading protected pages may include this page...
1828                         # Check each cascading level
1829                         # This is only for protection restrictions, not for all actions
1830                         if ( isset( $restrictions[$action] ) ) {
1831                                 foreach ( $restrictions[$action] as $right ) {
1832                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1833                                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1834                                                 $pages = '';
1835                                                 foreach ( $cascadingSources as $page )
1836                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1837                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1838                                         }
1839                                 }
1840                         }
1841                 }
1842
1843                 return $errors;
1844         }
1845
1846         /**
1847          * Check action permissions not already checked in checkQuickPermissions
1848          *
1849          * @param $action String the action to check
1850          * @param $user User to check
1851          * @param $errors Array list of current errors
1852          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1853          * @param $short Boolean short circuit on first error
1854          *
1855          * @return Array list of errors
1856          */
1857         private function checkActionPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1858                 global $wgDeleteRevisionsLimit, $wgLang;
1859
1860                 if ( $action == 'protect' ) {
1861                         if ( count( $this->getUserPermissionsErrorsInternal( 'edit', $user, $doExpensiveQueries, true ) ) ) {
1862                                 // If they can't edit, they shouldn't protect.
1863                                 $errors[] = array( 'protect-cantedit' );
1864                         }
1865                 } elseif ( $action == 'create' ) {
1866                         $title_protection = $this->getTitleProtection();
1867                         if( $title_protection ) {
1868                                 if( $title_protection['pt_create_perm'] == 'sysop' ) {
1869                                         $title_protection['pt_create_perm'] = 'protect'; // B/C
1870                                 }
1871                                 if( $title_protection['pt_create_perm'] == '' ||
1872                                         !$user->isAllowed( $title_protection['pt_create_perm'] ) )
1873                                 {
1874                                         $errors[] = array( 'titleprotected', User::whoIs( $title_protection['pt_user'] ), $title_protection['pt_reason'] );
1875                                 }
1876                         }
1877                 } elseif ( $action == 'move' ) {
1878                         // Check for immobile pages
1879                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1880                                 // Specific message for this case
1881                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1882                         } elseif ( !$this->isMovable() ) {
1883                                 // Less specific message for rarer cases
1884                                 $errors[] = array( 'immobile-source-page' );
1885                         }
1886                 } elseif ( $action == 'move-target' ) {
1887                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1888                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1889                         } elseif ( !$this->isMovable() ) {
1890                                 $errors[] = array( 'immobile-target-page' );
1891                         }
1892                 } elseif ( $action == 'delete' ) {
1893                         if ( $doExpensiveQueries && $wgDeleteRevisionsLimit
1894                                 && !$this->userCan( 'bigdelete', $user ) && $this->isBigDeletion() )
1895                         {
1896                                 $errors[] = array( 'delete-toobig', $wgLang->formatNum( $wgDeleteRevisionsLimit ) );
1897                         }
1898                 }
1899                 return $errors;
1900         }
1901
1902         /**
1903          * Check that the user isn't blocked from editting.
1904          *
1905          * @param $action String the action to check
1906          * @param $user User to check
1907          * @param $errors Array list of current errors
1908          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1909          * @param $short Boolean short circuit on first error
1910          *
1911          * @return Array list of errors
1912          */
1913         private function checkUserBlock( $action, $user, $errors, $doExpensiveQueries, $short ) {
1914                 // Account creation blocks handled at userlogin.
1915                 // Unblocking handled in SpecialUnblock
1916                 if( !$doExpensiveQueries || in_array( $action, array( 'createaccount', 'unblock' ) ) ) {
1917                         return $errors;
1918                 }
1919
1920                 global $wgContLang, $wgLang, $wgEmailConfirmToEdit;
1921
1922                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() ) {
1923                         $errors[] = array( 'confirmedittext' );
1924                 }
1925
1926                 if ( ( $action == 'edit' || $action == 'create' ) && !$user->isBlockedFrom( $this ) ) {
1927                         // Don't block the user from editing their own talk page unless they've been
1928                         // explicitly blocked from that too.
1929                 } elseif( $user->isBlocked() && $user->mBlock->prevents( $action ) !== false ) {
1930                         $block = $user->getBlock();
1931
1932                         // This is from OutputPage::blockedPage
1933                         // Copied at r23888 by werdna
1934
1935                         $id = $user->blockedBy();
1936                         $reason = $user->blockedFor();
1937                         if ( $reason == '' ) {
1938                                 $reason = wfMsg( 'blockednoreason' );
1939                         }
1940                         $ip = $user->getRequest()->getIP();
1941
1942                         if ( is_numeric( $id ) ) {
1943                                 $name = User::whoIs( $id );
1944                         } else {
1945                                 $name = $id;
1946                         }
1947
1948                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1949                         $blockid = $block->getId();
1950                         $blockExpiry = $block->getExpiry();
1951                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $block->mTimestamp ), true );
1952                         if ( $blockExpiry == 'infinity' ) {
1953                                 $blockExpiry = wfMessage( 'infiniteblock' )->text();
1954                         } else {
1955                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1956                         }
1957
1958                         $intended = strval( $block->getTarget() );
1959
1960                         $errors[] = array( ( $block->mAuto ? 'autoblockedtext' : 'blockedtext' ), $link, $reason, $ip, $name,
1961                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
1962                 }
1963
1964                 return $errors;
1965         }
1966
1967         /**
1968          * Check that the user is allowed to read this page.
1969          *
1970          * @param $action String the action to check
1971          * @param $user User to check
1972          * @param $errors Array list of current errors
1973          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1974          * @param $short Boolean short circuit on first error
1975          *
1976          * @return Array list of errors
1977          */
1978         private function checkReadPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1979                 global $wgWhitelistRead, $wgGroupPermissions, $wgRevokePermissions;
1980                 static $useShortcut = null;
1981
1982                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
1983                 if ( is_null( $useShortcut ) ) {
1984                         $useShortcut = true;
1985                         if ( empty( $wgGroupPermissions['*']['read'] ) ) {
1986                                 # Not a public wiki, so no shortcut
1987                                 $useShortcut = false;
1988                         } elseif ( !empty( $wgRevokePermissions ) ) {
1989                                 /**
1990                                  * Iterate through each group with permissions being revoked (key not included since we don't care
1991                                  * what the group name is), then check if the read permission is being revoked. If it is, then
1992                                  * we don't use the shortcut below since the user might not be able to read, even though anon
1993                                  * reading is allowed.
1994                                  */
1995                                 foreach ( $wgRevokePermissions as $perms ) {
1996                                         if ( !empty( $perms['read'] ) ) {
1997                                                 # We might be removing the read right from the user, so no shortcut
1998                                                 $useShortcut = false;
1999                                                 break;
2000                                         }
2001                                 }
2002                         }
2003                 }
2004
2005                 $whitelisted = false;
2006                 if ( $useShortcut ) {
2007                         # Shortcut for public wikis, allows skipping quite a bit of code
2008                         $whitelisted = true;
2009                 } elseif ( $user->isAllowed( 'read' ) ) {
2010                         # If the user is allowed to read pages, he is allowed to read all pages
2011                         $whitelisted = true;
2012                 } elseif ( $this->isSpecial( 'Userlogin' )
2013                         || $this->isSpecial( 'ChangePassword' )
2014                         || $this->isSpecial( 'PasswordReset' )
2015                 ) {
2016                         # Always grant access to the login page.
2017                         # Even anons need to be able to log in.
2018                         $whitelisted = true;
2019                 } elseif ( is_array( $wgWhitelistRead ) && count( $wgWhitelistRead ) ) {
2020                         # Time to check the whitelist
2021                         # Only do these checks is there's something to check against
2022                         $name = $this->getPrefixedText();
2023                         $dbName = $this->getPrefixedDBKey();
2024
2025                         // Check for explicit whitelisting with and without underscores
2026                         if ( in_array( $name, $wgWhitelistRead, true ) || in_array( $dbName, $wgWhitelistRead, true ) ) {
2027                                 $whitelisted = true;
2028                         } elseif ( $this->getNamespace() == NS_MAIN ) {
2029                                 # Old settings might have the title prefixed with
2030                                 # a colon for main-namespace pages
2031                                 if ( in_array( ':' . $name, $wgWhitelistRead ) ) {
2032                                         $whitelisted = true;
2033                                 }
2034                         } elseif ( $this->isSpecialPage() ) {
2035                                 # If it's a special page, ditch the subpage bit and check again
2036                                 $name = $this->getDBkey();
2037                                 list( $name, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $name );
2038                                 if ( $name !== false ) {
2039                                         $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
2040                                         if ( in_array( $pure, $wgWhitelistRead, true ) ) {
2041                                                 $whitelisted = true;
2042                                         }
2043                                 }
2044                         }
2045                 }
2046
2047                 if ( !$whitelisted ) {
2048                         # If the title is not whitelisted, give extensions a chance to do so...
2049                         wfRunHooks( 'TitleReadWhitelist', array( $this, $user, &$whitelisted ) );
2050                         if ( !$whitelisted ) {
2051                                 $errors[] = $this->missingPermissionError( $action, $short );
2052                         }
2053                 }
2054
2055                 return $errors;
2056         }
2057
2058         /**
2059          * Get a description array when the user doesn't have the right to perform
2060          * $action (i.e. when User::isAllowed() returns false)
2061          *
2062          * @param $action String the action to check
2063          * @param $short Boolean short circuit on first error
2064          * @return Array list of errors
2065          */
2066         private function missingPermissionError( $action, $short ) {
2067                 // We avoid expensive display logic for quickUserCan's and such
2068                 if ( $short ) {
2069                         return array( 'badaccess-group0' );
2070                 }
2071
2072                 $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
2073                         User::getGroupsWithPermission( $action ) );
2074
2075                 if ( count( $groups ) ) {
2076                         global $wgLang;
2077                         return array(
2078                                 'badaccess-groups',
2079                                 $wgLang->commaList( $groups ),
2080                                 count( $groups )
2081                         );
2082                 } else {
2083                         return array( 'badaccess-group0' );
2084                 }
2085         }
2086
2087         /**
2088          * Can $user perform $action on this page? This is an internal function,
2089          * which checks ONLY that previously checked by userCan (i.e. it leaves out
2090          * checks on wfReadOnly() and blocks)
2091          *
2092          * @param $action String action that permission needs to be checked for
2093          * @param $user User to check
2094          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary queries.
2095          * @param $short Bool Set this to true to stop after the first permission error.
2096          * @return Array of arrays of the arguments to wfMsg to explain permissions problems.
2097          */
2098         protected function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true, $short = false ) {
2099                 wfProfileIn( __METHOD__ );
2100
2101                 # Read has special handling
2102                 if ( $action == 'read' ) {
2103                         $checks = array(
2104                                 'checkPermissionHooks',
2105                                 'checkReadPermissions',
2106                         );
2107                 } else {
2108                         $checks = array(
2109                                 'checkQuickPermissions',
2110                                 'checkPermissionHooks',
2111                                 'checkSpecialsAndNSPermissions',
2112                                 'checkCSSandJSPermissions',
2113                                 'checkPageRestrictions',
2114                                 'checkCascadingSourcesRestrictions',
2115                                 'checkActionPermissions',
2116                                 'checkUserBlock'
2117                         );
2118                 }
2119
2120                 $errors = array();
2121                 while( count( $checks ) > 0 &&
2122                                 !( $short && count( $errors ) > 0 ) ) {
2123                         $method = array_shift( $checks );
2124                         $errors = $this->$method( $action, $user, $errors, $doExpensiveQueries, $short );
2125                 }
2126
2127                 wfProfileOut( __METHOD__ );
2128                 return $errors;
2129         }
2130
2131         /**
2132          * Protect css subpages of user pages: can $wgUser edit
2133          * this page?
2134          *
2135          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2136          * @return Bool
2137          */
2138         public function userCanEditCssSubpage() {
2139                 global $wgUser;
2140                 wfDeprecated( __METHOD__, '1.19' );
2141                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'editusercss' ) )
2142                         || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2143         }
2144
2145         /**
2146          * Protect js subpages of user pages: can $wgUser edit
2147          * this page?
2148          *
2149          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2150          * @return Bool
2151          */
2152         public function userCanEditJsSubpage() {
2153                 global $wgUser;
2154                 wfDeprecated( __METHOD__, '1.19' );
2155                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'edituserjs' ) )
2156                            || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2157         }
2158
2159         /**
2160          * Get a filtered list of all restriction types supported by this wiki.
2161          * @param bool $exists True to get all restriction types that apply to
2162          * titles that do exist, False for all restriction types that apply to
2163          * titles that do not exist
2164          * @return array
2165          */
2166         public static function getFilteredRestrictionTypes( $exists = true ) {
2167                 global $wgRestrictionTypes;
2168                 $types = $wgRestrictionTypes;
2169                 if ( $exists ) {
2170                         # Remove the create restriction for existing titles
2171                         $types = array_diff( $types, array( 'create' ) );
2172                 } else {
2173                         # Only the create and upload restrictions apply to non-existing titles
2174                         $types = array_intersect( $types, array( 'create', 'upload' ) );
2175                 }
2176                 return $types;
2177         }
2178
2179         /**
2180          * Returns restriction types for the current Title
2181          *
2182          * @return array applicable restriction types
2183          */
2184         public function getRestrictionTypes() {
2185                 if ( $this->isSpecialPage() ) {
2186                         return array();
2187                 }
2188
2189                 $types = self::getFilteredRestrictionTypes( $this->exists() );
2190
2191                 if ( $this->getNamespace() != NS_FILE ) {
2192                         # Remove the upload restriction for non-file titles
2193                         $types = array_diff( $types, array( 'upload' ) );
2194                 }
2195
2196                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
2197
2198                 wfDebug( __METHOD__ . ': applicable restrictions to [[' .
2199                         $this->getPrefixedText() . ']] are {' . implode( ',', $types ) . "}\n" );
2200
2201                 return $types;
2202         }
2203
2204         /**
2205          * Is this title subject to title protection?
2206          * Title protection is the one applied against creation of such title.
2207          *
2208          * @return Mixed An associative array representing any existent title
2209          *   protection, or false if there's none.
2210          */
2211         private function getTitleProtection() {
2212                 // Can't protect pages in special namespaces
2213                 if ( $this->getNamespace() < 0 ) {
2214                         return false;
2215                 }
2216
2217                 // Can't protect pages that exist.
2218                 if ( $this->exists() ) {
2219                         return false;
2220                 }
2221
2222                 if ( !isset( $this->mTitleProtection ) ) {
2223                         $dbr = wfGetDB( DB_SLAVE );
2224                         $res = $dbr->select( 'protected_titles', '*',
2225                                 array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2226                                 __METHOD__ );
2227
2228                         // fetchRow returns false if there are no rows.
2229                         $this->mTitleProtection = $dbr->fetchRow( $res );
2230                 }
2231                 return $this->mTitleProtection;
2232         }
2233
2234         /**
2235          * Update the title protection status
2236          *
2237          * @deprecated in 1.19; will be removed in 1.20. Use WikiPage::doUpdateRestrictions() instead.
2238          * @param $create_perm String Permission required for creation
2239          * @param $reason String Reason for protection
2240          * @param $expiry String Expiry timestamp
2241          * @return boolean true
2242          */
2243         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
2244                 wfDeprecated( __METHOD__, '1.19' );
2245
2246                 global $wgUser;
2247
2248                 $limit = array( 'create' => $create_perm );
2249                 $expiry = array( 'create' => $expiry );
2250
2251                 $page = WikiPage::factory( $this );
2252                 $status = $page->doUpdateRestrictions( $limit, $expiry, false, $reason, $wgUser );
2253
2254                 return $status->isOK();
2255         }
2256
2257         /**
2258          * Remove any title protection due to page existing
2259          */
2260         public function deleteTitleProtection() {
2261                 $dbw = wfGetDB( DB_MASTER );
2262
2263                 $dbw->delete(
2264                         'protected_titles',
2265                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2266                         __METHOD__
2267                 );
2268                 $this->mTitleProtection = false;
2269         }
2270
2271         /**
2272          * Is this page "semi-protected" - the *only* protection is autoconfirm?
2273          *
2274          * @param $action String Action to check (default: edit)
2275          * @return Bool
2276          */
2277         public function isSemiProtected( $action = 'edit' ) {
2278                 if ( $this->exists() ) {
2279                         $restrictions = $this->getRestrictions( $action );
2280                         if ( count( $restrictions ) > 0 ) {
2281                                 foreach ( $restrictions as $restriction ) {
2282                                         if ( strtolower( $restriction ) != 'autoconfirmed' ) {
2283                                                 return false;
2284                                         }
2285                                 }
2286                         } else {
2287                                 # Not protected
2288                                 return false;
2289                         }
2290                         return true;
2291                 } else {
2292                         # If it doesn't exist, it can't be protected
2293                         return false;
2294                 }
2295         }
2296
2297         /**
2298          * Does the title correspond to a protected article?
2299          *
2300          * @param $action String the action the page is protected from,
2301          * by default checks all actions.
2302          * @return Bool
2303          */
2304         public function isProtected( $action = '' ) {
2305                 global $wgRestrictionLevels;
2306
2307                 $restrictionTypes = $this->getRestrictionTypes();
2308
2309                 # Special pages have inherent protection
2310                 if( $this->isSpecialPage() ) {
2311                         return true;
2312                 }
2313
2314                 # Check regular protection levels
2315                 foreach ( $restrictionTypes as $type ) {
2316                         if ( $action == $type || $action == '' ) {
2317                                 $r = $this->getRestrictions( $type );
2318                                 foreach ( $wgRestrictionLevels as $level ) {
2319                                         if ( in_array( $level, $r ) && $level != '' ) {
2320                                                 return true;
2321                                         }
2322                                 }
2323                         }
2324                 }
2325
2326                 return false;
2327         }
2328
2329         /**
2330          * Determines if $user is unable to edit this page because it has been protected
2331          * by $wgNamespaceProtection.
2332          *
2333          * @param $user User object to check permissions
2334          * @return Bool
2335          */
2336         public function isNamespaceProtected( User $user ) {
2337                 global $wgNamespaceProtection;
2338
2339                 if ( isset( $wgNamespaceProtection[$this->mNamespace] ) ) {
2340                         foreach ( (array)$wgNamespaceProtection[$this->mNamespace] as $right ) {
2341                                 if ( $right != '' && !$user->isAllowed( $right ) ) {
2342                                         return true;
2343                                 }
2344                         }
2345                 }
2346                 return false;
2347         }
2348
2349         /**
2350          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
2351          *
2352          * @return Bool If the page is subject to cascading restrictions.
2353          */
2354         public function isCascadeProtected() {
2355                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
2356                 return ( $sources > 0 );
2357         }
2358
2359         /**
2360          * Cascading protection: Get the source of any cascading restrictions on this page.
2361          *
2362          * @param $getPages Bool Whether or not to retrieve the actual pages
2363          *        that the restrictions have come from.
2364          * @return Mixed Array of Title objects of the pages from which cascading restrictions
2365          *     have come, false for none, or true if such restrictions exist, but $getPages
2366          *     was not set.  The restriction array is an array of each type, each of which
2367          *     contains a array of unique groups.
2368          */
2369         public function getCascadeProtectionSources( $getPages = true ) {
2370                 global $wgContLang;
2371                 $pagerestrictions = array();
2372
2373                 if ( isset( $this->mCascadeSources ) && $getPages ) {
2374                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
2375                 } elseif ( isset( $this->mHasCascadingRestrictions ) && !$getPages ) {
2376                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
2377                 }
2378
2379                 wfProfileIn( __METHOD__ );
2380
2381                 $dbr = wfGetDB( DB_SLAVE );
2382
2383                 if ( $this->getNamespace() == NS_FILE ) {
2384                         $tables = array( 'imagelinks', 'page_restrictions' );
2385                         $where_clauses = array(
2386                                 'il_to' => $this->getDBkey(),
2387                                 'il_from=pr_page',
2388                                 'pr_cascade' => 1
2389                         );
2390                 } else {
2391                         $tables = array( 'templatelinks', 'page_restrictions' );
2392                         $where_clauses = array(
2393                                 'tl_namespace' => $this->getNamespace(),
2394                                 'tl_title' => $this->getDBkey(),
2395                                 'tl_from=pr_page',
2396                                 'pr_cascade' => 1
2397                         );
2398                 }
2399
2400                 if ( $getPages ) {
2401                         $cols = array( 'pr_page', 'page_namespace', 'page_title',
2402                                                    'pr_expiry', 'pr_type', 'pr_level' );
2403                         $where_clauses[] = 'page_id=pr_page';
2404                         $tables[] = 'page';
2405                 } else {
2406                         $cols = array( 'pr_expiry' );
2407                 }
2408
2409                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
2410
2411                 $sources = $getPages ? array() : false;
2412                 $now = wfTimestampNow();
2413                 $purgeExpired = false;
2414
2415                 foreach ( $res as $row ) {
2416                         $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2417                         if ( $expiry > $now ) {
2418                                 if ( $getPages ) {
2419                                         $page_id = $row->pr_page;
2420                                         $page_ns = $row->page_namespace;
2421                                         $page_title = $row->page_title;
2422                                         $sources[$page_id] = Title::makeTitle( $page_ns, $page_title );
2423                                         # Add groups needed for each restriction type if its not already there
2424                                         # Make sure this restriction type still exists
2425
2426                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
2427                                                 $pagerestrictions[$row->pr_type] = array();
2428                                         }
2429
2430                                         if ( isset( $pagerestrictions[$row->pr_type] ) &&
2431                                                  !in_array( $row->pr_level, $pagerestrictions[$row->pr_type] ) ) {
2432                                                 $pagerestrictions[$row->pr_type][] = $row->pr_level;
2433                                         }
2434                                 } else {
2435                                         $sources = true;
2436                                 }
2437                         } else {
2438                                 // Trigger lazy purge of expired restrictions from the db
2439                                 $purgeExpired = true;
2440                         }
2441                 }
2442                 if ( $purgeExpired ) {
2443                         Title::purgeExpiredRestrictions();
2444                 }
2445
2446                 if ( $getPages ) {
2447                         $this->mCascadeSources = $sources;
2448                         $this->mCascadingRestrictions = $pagerestrictions;
2449                 } else {
2450                         $this->mHasCascadingRestrictions = $sources;
2451                 }
2452
2453                 wfProfileOut( __METHOD__ );
2454                 return array( $sources, $pagerestrictions );
2455         }
2456
2457         /**
2458          * Accessor/initialisation for mRestrictions
2459          *
2460          * @param $action String action that permission needs to be checked for
2461          * @return Array of Strings the array of groups allowed to edit this article
2462          */
2463         public function getRestrictions( $action ) {
2464                 if ( !$this->mRestrictionsLoaded ) {
2465                         $this->loadRestrictions();
2466                 }
2467                 return isset( $this->mRestrictions[$action] )
2468                                 ? $this->mRestrictions[$action]
2469                                 : array();
2470         }
2471
2472         /**
2473          * Get the expiry time for the restriction against a given action
2474          *
2475          * @return String|Bool 14-char timestamp, or 'infinity' if the page is protected forever
2476          *      or not protected at all, or false if the action is not recognised.
2477          */
2478         public function getRestrictionExpiry( $action ) {
2479                 if ( !$this->mRestrictionsLoaded ) {
2480                         $this->loadRestrictions();
2481                 }
2482                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2483         }
2484
2485         /**
2486          * Returns cascading restrictions for the current article
2487          *
2488          * @return Boolean
2489          */
2490         function areRestrictionsCascading() {
2491                 if ( !$this->mRestrictionsLoaded ) {
2492                         $this->loadRestrictions();
2493                 }
2494
2495                 return $this->mCascadeRestriction;
2496         }
2497
2498         /**
2499          * Loads a string into mRestrictions array
2500          *
2501          * @param $res Resource restrictions as an SQL result.
2502          * @param $oldFashionedRestrictions String comma-separated list of page
2503          *        restrictions from page table (pre 1.10)
2504          */
2505         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
2506                 $rows = array();
2507
2508                 foreach ( $res as $row ) {
2509                         $rows[] = $row;
2510                 }
2511
2512                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
2513         }
2514
2515         /**
2516          * Compiles list of active page restrictions from both page table (pre 1.10)
2517          * and page_restrictions table for this existing page.
2518          * Public for usage by LiquidThreads.
2519          *
2520          * @param $rows array of db result objects
2521          * @param $oldFashionedRestrictions string comma-separated list of page
2522          *        restrictions from page table (pre 1.10)
2523          */
2524         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
2525                 global $wgContLang;
2526                 $dbr = wfGetDB( DB_SLAVE );
2527
2528                 $restrictionTypes = $this->getRestrictionTypes();
2529
2530                 foreach ( $restrictionTypes as $type ) {
2531                         $this->mRestrictions[$type] = array();
2532                         $this->mRestrictionsExpiry[$type] = $wgContLang->formatExpiry( '', TS_MW );
2533                 }
2534
2535                 $this->mCascadeRestriction = false;
2536
2537                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2538
2539                 if ( $oldFashionedRestrictions === null ) {
2540                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2541                                 array( 'page_id' => $this->getArticleId() ), __METHOD__ );
2542                 }
2543
2544                 if ( $oldFashionedRestrictions != '' ) {
2545
2546                         foreach ( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2547                                 $temp = explode( '=', trim( $restrict ) );
2548                                 if ( count( $temp ) == 1 ) {
2549                                         // old old format should be treated as edit/move restriction
2550                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2551                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2552                                 } else {
2553                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
2554                                 }
2555                         }
2556
2557                         $this->mOldRestrictions = true;
2558
2559                 }
2560
2561                 if ( count( $rows ) ) {
2562                         # Current system - load second to make them override.
2563                         $now = wfTimestampNow();
2564                         $purgeExpired = false;
2565
2566                         # Cycle through all the restrictions.
2567                         foreach ( $rows as $row ) {
2568
2569                                 // Don't take care of restrictions types that aren't allowed
2570                                 if ( !in_array( $row->pr_type, $restrictionTypes ) )
2571                                         continue;
2572
2573                                 // This code should be refactored, now that it's being used more generally,
2574                                 // But I don't really see any harm in leaving it in Block for now -werdna
2575                                 $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2576
2577                                 // Only apply the restrictions if they haven't expired!
2578                                 if ( !$expiry || $expiry > $now ) {
2579                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2580                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2581
2582                                         $this->mCascadeRestriction |= $row->pr_cascade;
2583                                 } else {
2584                                         // Trigger a lazy purge of expired restrictions
2585                                         $purgeExpired = true;
2586                                 }
2587                         }
2588
2589                         if ( $purgeExpired ) {
2590                                 Title::purgeExpiredRestrictions();
2591                         }
2592                 }
2593
2594                 $this->mRestrictionsLoaded = true;
2595         }
2596
2597         /**
2598          * Load restrictions from the page_restrictions table
2599          *
2600          * @param $oldFashionedRestrictions String comma-separated list of page
2601          *        restrictions from page table (pre 1.10)
2602          */
2603         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2604                 global $wgContLang;
2605                 if ( !$this->mRestrictionsLoaded ) {
2606                         if ( $this->exists() ) {
2607                                 $dbr = wfGetDB( DB_SLAVE );
2608
2609                                 $res = $dbr->select(
2610                                         'page_restrictions',
2611                                         '*',
2612                                         array( 'pr_page' => $this->getArticleId() ),
2613                                         __METHOD__
2614                                 );
2615
2616                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2617                         } else {
2618                                 $title_protection = $this->getTitleProtection();
2619
2620                                 if ( $title_protection ) {
2621                                         $now = wfTimestampNow();
2622                                         $expiry = $wgContLang->formatExpiry( $title_protection['pt_expiry'], TS_MW );
2623
2624                                         if ( !$expiry || $expiry > $now ) {
2625                                                 // Apply the restrictions
2626                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2627                                                 $this->mRestrictions['create'] = explode( ',', trim( $title_protection['pt_create_perm'] ) );
2628                                         } else { // Get rid of the old restrictions
2629                                                 Title::purgeExpiredRestrictions();
2630                                                 $this->mTitleProtection = false;
2631                                         }
2632                                 } else {
2633                                         $this->mRestrictionsExpiry['create'] = $wgContLang->formatExpiry( '', TS_MW );
2634                                 }
2635                                 $this->mRestrictionsLoaded = true;
2636                         }
2637                 }
2638         }
2639
2640         /**
2641          * Flush the protection cache in this object and force reload from the database.
2642          * This is used when updating protection from WikiPage::doUpdateRestrictions().
2643          */
2644         public function flushRestrictions() {
2645                 $this->mRestrictionsLoaded = false;
2646                 $this->mTitleProtection = null;
2647         }
2648
2649         /**
2650          * Purge expired restrictions from the page_restrictions table
2651          */
2652         static function purgeExpiredRestrictions() {
2653                 $dbw = wfGetDB( DB_MASTER );
2654                 $dbw->delete(
2655                         'page_restrictions',
2656                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2657                         __METHOD__
2658                 );
2659
2660                 $dbw->delete(
2661                         'protected_titles',
2662                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2663                         __METHOD__
2664                 );
2665         }
2666
2667         /**
2668          * Does this have subpages?  (Warning, usually requires an extra DB query.)
2669          *
2670          * @return Bool
2671          */
2672         public function hasSubpages() {
2673                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
2674                         # Duh
2675                         return false;
2676                 }
2677
2678                 # We dynamically add a member variable for the purpose of this method
2679                 # alone to cache the result.  There's no point in having it hanging
2680                 # around uninitialized in every Title object; therefore we only add it
2681                 # if needed and don't declare it statically.
2682                 if ( isset( $this->mHasSubpages ) ) {
2683                         return $this->mHasSubpages;
2684                 }
2685
2686                 $subpages = $this->getSubpages( 1 );
2687                 if ( $subpages instanceof TitleArray ) {
2688                         return $this->mHasSubpages = (bool)$subpages->count();
2689                 }
2690                 return $this->mHasSubpages = false;
2691         }
2692
2693         /**
2694          * Get all subpages of this page.
2695          *
2696          * @param $limit Int maximum number of subpages to fetch; -1 for no limit
2697          * @return mixed TitleArray, or empty array if this page's namespace
2698          *  doesn't allow subpages
2699          */
2700         public function getSubpages( $limit = -1 ) {
2701                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
2702                         return array();
2703                 }
2704
2705                 $dbr = wfGetDB( DB_SLAVE );
2706                 $conds['page_namespace'] = $this->getNamespace();
2707                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
2708                 $options = array();
2709                 if ( $limit > -1 ) {
2710                         $options['LIMIT'] = $limit;
2711                 }
2712                 return $this->mSubpages = TitleArray::newFromResult(
2713                         $dbr->select( 'page',
2714                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
2715                                 $conds,
2716                                 __METHOD__,
2717                                 $options
2718                         )
2719                 );
2720         }
2721
2722         /**
2723          * Is there a version of this page in the deletion archive?
2724          *
2725          * @return Int the number of archived revisions
2726          */
2727         public function isDeleted() {
2728                 if ( $this->getNamespace() < 0 ) {
2729                         $n = 0;
2730                 } else {
2731                         $dbr = wfGetDB( DB_SLAVE );
2732
2733                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2734                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2735                                 __METHOD__
2736                         );
2737                         if ( $this->getNamespace() == NS_FILE ) {
2738                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2739                                         array( 'fa_name' => $this->getDBkey() ),
2740                                         __METHOD__
2741                                 );
2742                         }
2743                 }
2744                 return (int)$n;
2745         }
2746
2747         /**
2748          * Is there a version of this page in the deletion archive?
2749          *
2750          * @return Boolean
2751          */
2752         public function isDeletedQuick() {
2753                 if ( $this->getNamespace() < 0 ) {
2754                         return false;
2755                 }
2756                 $dbr = wfGetDB( DB_SLAVE );
2757                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2758                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2759                         __METHOD__
2760                 );
2761                 if ( !$deleted && $this->getNamespace() == NS_FILE ) {
2762                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2763                                 array( 'fa_name' => $this->getDBkey() ),
2764                                 __METHOD__
2765                         );
2766                 }
2767                 return $deleted;
2768         }
2769
2770         /**
2771          * Get the article ID for this Title from the link cache,
2772          * adding it if necessary
2773          *
2774          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select
2775          *  for update
2776          * @return Int the ID
2777          */
2778         public function getArticleID( $flags = 0 ) {
2779                 if ( $this->getNamespace() < 0 ) {
2780                         return $this->mArticleID = 0;
2781                 }
2782                 $linkCache = LinkCache::singleton();
2783                 if ( $flags & self::GAID_FOR_UPDATE ) {
2784                         $oldUpdate = $linkCache->forUpdate( true );
2785                         $linkCache->clearLink( $this );
2786                         $this->mArticleID = $linkCache->addLinkObj( $this );
2787                         $linkCache->forUpdate( $oldUpdate );
2788                 } else {
2789                         if ( -1 == $this->mArticleID ) {
2790                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2791                         }
2792                 }
2793                 return $this->mArticleID;
2794         }
2795
2796         /**
2797          * Is this an article that is a redirect page?
2798          * Uses link cache, adding it if necessary
2799          *
2800          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2801          * @return Bool
2802          */
2803         public function isRedirect( $flags = 0 ) {
2804                 if ( !is_null( $this->mRedirect ) ) {
2805                         return $this->mRedirect;
2806                 }
2807                 # Calling getArticleID() loads the field from cache as needed
2808                 if ( !$this->getArticleID( $flags ) ) {
2809                         return $this->mRedirect = false;
2810                 }
2811                 $linkCache = LinkCache::singleton();
2812                 $this->mRedirect = (bool)$linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2813
2814                 return $this->mRedirect;
2815         }
2816
2817         /**
2818          * What is the length of this page?
2819          * Uses link cache, adding it if necessary
2820          *
2821          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2822          * @return Int
2823          */
2824         public function getLength( $flags = 0 ) {
2825                 if ( $this->mLength != -1 ) {
2826                         return $this->mLength;
2827                 }
2828                 # Calling getArticleID() loads the field from cache as needed
2829                 if ( !$this->getArticleID( $flags ) ) {
2830                         return $this->mLength = 0;
2831                 }
2832                 $linkCache = LinkCache::singleton();
2833                 $this->mLength = intval( $linkCache->getGoodLinkFieldObj( $this, 'length' ) );
2834
2835                 return $this->mLength;
2836         }
2837
2838         /**
2839          * What is the page_latest field for this page?
2840          *
2841          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2842          * @return Int or 0 if the page doesn't exist
2843          */
2844         public function getLatestRevID( $flags = 0 ) {
2845                 if ( $this->mLatestID !== false ) {
2846                         return intval( $this->mLatestID );
2847                 }
2848                 # Calling getArticleID() loads the field from cache as needed
2849                 if ( !$this->getArticleID( $flags ) ) {
2850                         return $this->mLatestID = 0;
2851                 }
2852                 $linkCache = LinkCache::singleton();
2853                 $this->mLatestID = intval( $linkCache->getGoodLinkFieldObj( $this, 'revision' ) );
2854
2855                 return $this->mLatestID;
2856         }
2857
2858         /**
2859          * This clears some fields in this object, and clears any associated
2860          * keys in the "bad links" section of the link cache.
2861          *
2862          * - This is called from WikiPage::doEdit() and WikiPage::insertOn() to allow
2863          * loading of the new page_id. It's also called from
2864          * WikiPage::doDeleteArticle()
2865          *
2866          * @param $newid Int the new Article ID
2867          */
2868         public function resetArticleID( $newid ) {
2869                 $linkCache = LinkCache::singleton();
2870                 $linkCache->clearLink( $this );
2871
2872                 if ( $newid === false ) {
2873                         $this->mArticleID = -1;
2874                 } else {
2875                         $this->mArticleID = intval( $newid );
2876                 }
2877                 $this->mRestrictionsLoaded = false;
2878                 $this->mRestrictions = array();
2879                 $this->mRedirect = null;
2880                 $this->mLength = -1;
2881                 $this->mLatestID = false;
2882                 $this->mEstimateRevisions = null;
2883         }
2884
2885         /**
2886          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
2887          *
2888          * @param $text String containing title to capitalize
2889          * @param $ns int namespace index, defaults to NS_MAIN
2890          * @return String containing capitalized title
2891          */
2892         public static function capitalize( $text, $ns = NS_MAIN ) {
2893                 global $wgContLang;
2894
2895                 if ( MWNamespace::isCapitalized( $ns ) ) {
2896                         return $wgContLang->ucfirst( $text );
2897                 } else {
2898                         return $text;
2899                 }
2900         }
2901
2902         /**
2903          * Secure and split - main initialisation function for this object
2904          *
2905          * Assumes that mDbkeyform has been set, and is urldecoded
2906          * and uses underscores, but not otherwise munged.  This function
2907          * removes illegal characters, splits off the interwiki and
2908          * namespace prefixes, sets the other forms, and canonicalizes
2909          * everything.
2910          *
2911          * @return Bool true on success
2912          */
2913         private function secureAndSplit() {
2914                 global $wgContLang, $wgLocalInterwiki;
2915
2916                 # Initialisation
2917                 $this->mInterwiki = $this->mFragment = '';
2918                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2919
2920                 $dbkey = $this->mDbkeyform;
2921
2922                 # Strip Unicode bidi override characters.
2923                 # Sometimes they slip into cut-n-pasted page titles, where the
2924                 # override chars get included in list displays.
2925                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
2926
2927                 # Clean up whitespace
2928                 # Note: use of the /u option on preg_replace here will cause
2929                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
2930                 # conveniently disabling them.
2931                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
2932                 $dbkey = trim( $dbkey, '_' );
2933
2934                 if ( $dbkey == '' ) {
2935                         return false;
2936                 }
2937
2938                 if ( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2939                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2940                         return false;
2941                 }
2942
2943                 $this->mDbkeyform = $dbkey;
2944
2945                 # Initial colon indicates main namespace rather than specified default
2946                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
2947                 if ( ':' == $dbkey[0] ) {
2948                         $this->mNamespace = NS_MAIN;
2949                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
2950                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
2951                 }
2952
2953                 # Namespace or interwiki prefix
2954                 $firstPass = true;
2955                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
2956                 do {
2957                         $m = array();
2958                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
2959                                 $p = $m[1];
2960                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
2961                                         # Ordinary namespace
2962                                         $dbkey = $m[2];
2963                                         $this->mNamespace = $ns;
2964                                         # For Talk:X pages, check if X has a "namespace" prefix
2965                                         if ( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
2966                                                 if ( $wgContLang->getNsIndex( $x[1] ) ) {
2967                                                         # Disallow Talk:File:x type titles...
2968                                                         return false;
2969                                                 } elseif ( Interwiki::isValidInterwiki( $x[1] ) ) {
2970                                                         # Disallow Talk:Interwiki:x type titles...
2971                                                         return false;
2972                                                 }
2973                                         }
2974                                 } elseif ( Interwiki::isValidInterwiki( $p ) ) {
2975                                         if ( !$firstPass ) {
2976                                                 # Can't make a local interwiki link to an interwiki link.
2977                                                 # That's just crazy!
2978                                                 return false;
2979                                         }
2980
2981                                         # Interwiki link
2982                                         $dbkey = $m[2];
2983                                         $this->mInterwiki = $wgContLang->lc( $p );
2984
2985                                         # Redundant interwiki prefix to the local wiki
2986                                         if ( $wgLocalInterwiki !== false
2987                                                 && 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) )
2988                                         {
2989                                                 if ( $dbkey == '' ) {
2990                                                         # Can't have an empty self-link
2991                                                         return false;
2992                                                 }
2993                                                 $this->mInterwiki = '';
2994                                                 $firstPass = false;
2995                                                 # Do another namespace split...
2996                                                 continue;
2997                                         }
2998
2999                                         # If there's an initial colon after the interwiki, that also
3000                                         # resets the default namespace
3001                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
3002                                                 $this->mNamespace = NS_MAIN;
3003                                                 $dbkey = substr( $dbkey, 1 );
3004                                         }
3005                                 }
3006                                 # If there's no recognized interwiki or namespace,
3007                                 # then let the colon expression be part of the title.
3008                         }
3009                         break;
3010                 } while ( true );
3011
3012                 # We already know that some pages won't be in the database!
3013                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
3014                         $this->mArticleID = 0;
3015                 }
3016                 $fragment = strstr( $dbkey, '#' );
3017                 if ( false !== $fragment ) {
3018                         $this->setFragment( $fragment );
3019                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
3020                         # remove whitespace again: prevents "Foo_bar_#"
3021                         # becoming "Foo_bar_"
3022                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
3023                 }
3024
3025                 # Reject illegal characters.
3026                 $rxTc = self::getTitleInvalidRegex();
3027                 if ( preg_match( $rxTc, $dbkey ) ) {
3028                         return false;
3029                 }
3030
3031                 # Pages with "/./" or "/../" appearing in the URLs will often be un-
3032                 # reachable due to the way web browsers deal with 'relative' URLs.
3033                 # Also, they conflict with subpage syntax.  Forbid them explicitly.
3034                 if ( strpos( $dbkey, '.' ) !== false &&
3035                          ( $dbkey === '.' || $dbkey === '..' ||
3036                            strpos( $dbkey, './' ) === 0  ||
3037                            strpos( $dbkey, '../' ) === 0 ||
3038                            strpos( $dbkey, '/./' ) !== false ||
3039                            strpos( $dbkey, '/../' ) !== false  ||
3040                            substr( $dbkey, -2 ) == '/.' ||
3041                            substr( $dbkey, -3 ) == '/..' ) )
3042                 {
3043                         return false;
3044                 }
3045
3046                 # Magic tilde sequences? Nu-uh!
3047                 if ( strpos( $dbkey, '~~~' ) !== false ) {
3048                         return false;
3049                 }
3050
3051                 # Limit the size of titles to 255 bytes. This is typically the size of the
3052                 # underlying database field. We make an exception for special pages, which
3053                 # don't need to be stored in the database, and may edge over 255 bytes due
3054                 # to subpage syntax for long titles, e.g. [[Special:Block/Long name]]
3055                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
3056                   strlen( $dbkey ) > 512 )
3057                 {
3058                         return false;
3059                 }
3060
3061                 # Normally, all wiki links are forced to have an initial capital letter so [[foo]]
3062                 # and [[Foo]] point to the same place.  Don't force it for interwikis, since the
3063                 # other site might be case-sensitive.
3064                 $this->mUserCaseDBKey = $dbkey;
3065                 if ( $this->mInterwiki == '' ) {
3066                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
3067                 }
3068
3069                 # Can't make a link to a namespace alone... "empty" local links can only be
3070                 # self-links with a fragment identifier.
3071                 if ( $dbkey == '' && $this->mInterwiki == '' && $this->mNamespace != NS_MAIN ) {
3072                         return false;
3073                 }
3074
3075                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
3076                 // IP names are not allowed for accounts, and can only be referring to
3077                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
3078                 // there are numerous ways to present the same IP. Having sp:contribs scan
3079                 // them all is silly and having some show the edits and others not is
3080                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
3081                 $dbkey = ( $this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK )
3082                         ? IP::sanitizeIP( $dbkey )
3083                         : $dbkey;
3084
3085                 // Any remaining initial :s are illegal.
3086                 if ( $dbkey !== '' && ':' == $dbkey[0] ) {
3087                         return false;
3088                 }
3089
3090                 # Fill fields
3091                 $this->mDbkeyform = $dbkey;
3092                 $this->mUrlform = wfUrlencode( $dbkey );
3093
3094                 $this->mTextform = str_replace( '_', ' ', $dbkey );
3095
3096                 return true;
3097         }
3098
3099         /**
3100          * Get an array of Title objects linking to this Title
3101          * Also stores the IDs in the link cache.
3102          *
3103          * WARNING: do not use this function on arbitrary user-supplied titles!
3104          * On heavily-used templates it will max out the memory.
3105          *
3106          * @param $options Array: may be FOR UPDATE
3107          * @param $table String: table name
3108          * @param $prefix String: fields prefix
3109          * @return Array of Title objects linking here
3110          */
3111         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3112                 if ( count( $options ) > 0 ) {
3113                         $db = wfGetDB( DB_MASTER );
3114                 } else {
3115                         $db = wfGetDB( DB_SLAVE );
3116                 }
3117
3118                 $res = $db->select(
3119                         array( 'page', $table ),
3120                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ),
3121                         array(
3122                                 "{$prefix}_from=page_id",
3123                                 "{$prefix}_namespace" => $this->getNamespace(),
3124                                 "{$prefix}_title"     => $this->getDBkey() ),
3125                         __METHOD__,
3126                         $options
3127                 );
3128
3129                 $retVal = array();
3130                 if ( $res->numRows() ) {
3131                         $linkCache = LinkCache::singleton();
3132                         foreach ( $res as $row ) {
3133                                 $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title );
3134                                 if ( $titleObj ) {
3135                                         $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3136                                         $retVal[] = $titleObj;
3137                                 }
3138                         }
3139                 }
3140                 return $retVal;
3141         }
3142
3143         /**
3144          * Get an array of Title objects using this Title as a template
3145          * Also stores the IDs in the link cache.
3146          *
3147          * WARNING: do not use this function on arbitrary user-supplied titles!
3148          * On heavily-used templates it will max out the memory.
3149          *
3150          * @param $options Array: may be FOR UPDATE
3151          * @return Array of Title the Title objects linking here
3152          */
3153         public function getTemplateLinksTo( $options = array() ) {
3154                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
3155         }
3156
3157         /**
3158          * Get an array of Title objects linked from this Title
3159          * Also stores the IDs in the link cache.
3160          *
3161          * WARNING: do not use this function on arbitrary user-supplied titles!
3162          * On heavily-used templates it will max out the memory.
3163          *
3164          * @param $options Array: may be FOR UPDATE
3165          * @param $table String: table name
3166          * @param $prefix String: fields prefix
3167          * @return Array of Title objects linking here
3168          */
3169         public function getLinksFrom( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3170                 $id = $this->getArticleId();
3171
3172                 # If the page doesn't exist; there can't be any link from this page
3173                 if ( !$id ) {
3174                         return array();
3175                 }
3176
3177                 if ( count( $options ) > 0 ) {
3178                         $db = wfGetDB( DB_MASTER );
3179                 } else {
3180                         $db = wfGetDB( DB_SLAVE );
3181                 }
3182
3183                 $namespaceFiled = "{$prefix}_namespace";
3184                 $titleField = "{$prefix}_title";
3185
3186                 $res = $db->select(
3187                         array( $table, 'page' ),
3188                         array( $namespaceFiled, $titleField, 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ),
3189                         array( "{$prefix}_from" => $id ),
3190                         __METHOD__,
3191                         $options,
3192                         array( 'page' => array( 'LEFT JOIN', array( "page_namespace=$namespaceFiled", "page_title=$titleField" ) ) )
3193                 );
3194
3195                 $retVal = array();
3196                 if ( $res->numRows() ) {
3197                         $linkCache = LinkCache::singleton();
3198                         foreach ( $res as $row ) {
3199                                 $titleObj = Title::makeTitle( $row->$namespaceFiled, $row->$titleField );
3200                                 if ( $titleObj ) {
3201                                         if ( $row->page_id ) {
3202                                                 $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3203                                         } else {
3204                                                 $linkCache->addBadLinkObj( $titleObj );
3205                                         }
3206                                         $retVal[] = $titleObj;
3207                                 }
3208                         }
3209                 }
3210                 return $retVal;
3211         }
3212
3213         /**
3214          * Get an array of Title objects used on this Title as a template
3215          * Also stores the IDs in the link cache.
3216          *
3217          * WARNING: do not use this function on arbitrary user-supplied titles!
3218          * On heavily-used templates it will max out the memory.
3219          *
3220          * @param $options Array: may be FOR UPDATE
3221          * @return Array of Title the Title objects used here
3222          */
3223         public function getTemplateLinksFrom( $options = array() ) {
3224                 return $this->getLinksFrom( $options, 'templatelinks', 'tl' );
3225         }
3226
3227         /**
3228          * Get an array of Title objects referring to non-existent articles linked from this page
3229          *
3230          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
3231          * @return Array of Title the Title objects
3232          */
3233         public function getBrokenLinksFrom() {
3234                 if ( $this->getArticleId() == 0 ) {
3235                         # All links from article ID 0 are false positives
3236                         return array();
3237                 }
3238
3239                 $dbr = wfGetDB( DB_SLAVE );
3240                 $res = $dbr->select(
3241                         array( 'page', 'pagelinks' ),
3242                         array( 'pl_namespace', 'pl_title' ),
3243                         array(
3244                                 'pl_from' => $this->getArticleId(),
3245                                 'page_namespace IS NULL'
3246                         ),
3247                         __METHOD__, array(),
3248                         array(
3249                                 'page' => array(
3250                                         'LEFT JOIN',
3251                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
3252                                 )
3253                         )
3254                 );
3255
3256                 $retVal = array();
3257                 foreach ( $res as $row ) {
3258                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
3259                 }
3260                 return $retVal;
3261         }
3262
3263
3264         /**
3265          * Get a list of URLs to purge from the Squid cache when this
3266          * page changes
3267          *
3268          * @return Array of String the URLs
3269          */
3270         public function getSquidURLs() {
3271                 global $wgContLang;
3272
3273                 $urls = array(
3274                         $this->getInternalURL(),
3275                         $this->getInternalURL( 'action=history' )
3276                 );
3277
3278                 // purge variant urls as well
3279                 if ( $wgContLang->hasVariants() ) {
3280                         $variants = $wgContLang->getVariants();
3281                         foreach ( $variants as $vCode ) {
3282                                 $urls[] = $this->getInternalURL( '', $vCode );
3283                         }
3284                 }
3285
3286                 return $urls;
3287         }
3288
3289         /**
3290          * Purge all applicable Squid URLs
3291          */
3292         public function purgeSquid() {
3293                 global $wgUseSquid;
3294                 if ( $wgUseSquid ) {
3295                         $urls = $this->getSquidURLs();
3296                         $u = new SquidUpdate( $urls );
3297                         $u->doUpdate();
3298                 }
3299         }
3300
3301         /**
3302          * Move this page without authentication
3303          *
3304          * @param $nt Title the new page Title
3305          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3306          */
3307         public function moveNoAuth( &$nt ) {
3308                 return $this->moveTo( $nt, false );
3309         }
3310
3311         /**
3312          * Check whether a given move operation would be valid.
3313          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
3314          *
3315          * @param $nt Title the new title
3316          * @param $auth Bool indicates whether $wgUser's permissions
3317          *  should be checked
3318          * @param $reason String is the log summary of the move, used for spam checking
3319          * @return Mixed True on success, getUserPermissionsErrors()-like array on failure
3320          */
3321         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
3322                 global $wgUser;
3323
3324                 $errors = array();
3325                 if ( !$nt ) {
3326                         // Normally we'd add this to $errors, but we'll get
3327                         // lots of syntax errors if $nt is not an object
3328                         return array( array( 'badtitletext' ) );
3329                 }
3330                 if ( $this->equals( $nt ) ) {
3331                         $errors[] = array( 'selfmove' );
3332                 }
3333                 if ( !$this->isMovable() ) {
3334                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
3335                 }
3336                 if ( $nt->getInterwiki() != '' ) {
3337                         $errors[] = array( 'immobile-target-namespace-iw' );
3338                 }
3339                 if ( !$nt->isMovable() ) {
3340                         $errors[] = array( 'immobile-target-namespace', $nt->getNsText() );
3341                 }
3342
3343                 $oldid = $this->getArticleID();
3344                 $newid = $nt->getArticleID();
3345
3346                 if ( strlen( $nt->getDBkey() ) < 1 ) {
3347                         $errors[] = array( 'articleexists' );
3348                 }
3349                 if ( ( $this->getDBkey() == '' ) ||
3350                          ( !$oldid ) ||
3351                          ( $nt->getDBkey() == '' ) ) {
3352                         $errors[] = array( 'badarticleerror' );
3353                 }
3354
3355                 // Image-specific checks
3356                 if ( $this->getNamespace() == NS_FILE ) {
3357                         $errors = array_merge( $errors, $this->validateFileMoveOperation( $nt ) );
3358                 }
3359
3360                 if ( $nt->getNamespace() == NS_FILE && $this->getNamespace() != NS_FILE ) {
3361                         $errors[] = array( 'nonfile-cannot-move-to-file' );
3362                 }
3363
3364                 if ( $auth ) {
3365                         $errors = wfMergeErrorArrays( $errors,
3366                                 $this->getUserPermissionsErrors( 'move', $wgUser ),
3367                                 $this->getUserPermissionsErrors( 'edit', $wgUser ),
3368                                 $nt->getUserPermissionsErrors( 'move-target', $wgUser ),
3369                                 $nt->getUserPermissionsErrors( 'edit', $wgUser ) );
3370                 }
3371
3372                 $match = EditPage::matchSummarySpamRegex( $reason );
3373                 if ( $match !== false ) {
3374                         // This is kind of lame, won't display nice
3375                         $errors[] = array( 'spamprotectiontext' );
3376                 }
3377
3378                 $err = null;
3379                 if ( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
3380                         $errors[] = array( 'hookaborted', $err );
3381                 }
3382
3383                 # The move is allowed only if (1) the target doesn't exist, or
3384                 # (2) the target is a redirect to the source, and has no history
3385                 # (so we can undo bad moves right after they're done).
3386
3387                 if ( 0 != $newid ) { # Target exists; check for validity
3388                         if ( !$this->isValidMoveTarget( $nt ) ) {
3389                                 $errors[] = array( 'articleexists' );
3390                         }
3391                 } else {
3392                         $tp = $nt->getTitleProtection();
3393                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
3394                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
3395                                 $errors[] = array( 'cantmove-titleprotected' );
3396                         }
3397                 }
3398                 if ( empty( $errors ) ) {
3399                         return true;
3400                 }
3401                 return $errors;
3402         }
3403
3404         /**
3405          * Check if the requested move target is a valid file move target
3406          * @param Title $nt Target title
3407          * @return array List of errors
3408          */
3409         protected function validateFileMoveOperation( $nt ) {
3410                 global $wgUser;
3411
3412                 $errors = array();
3413
3414                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is not allowed until below
3415
3416                 $file = wfLocalFile( $this );
3417                 if ( $file->exists() ) {
3418                         if ( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
3419                                 $errors[] = array( 'imageinvalidfilename' );
3420                         }
3421                         if ( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
3422                                 $errors[] = array( 'imagetypemismatch' );
3423                         }
3424                 }
3425
3426                 if ( $nt->getNamespace() != NS_FILE ) {
3427                         $errors[] = array( 'imagenocrossnamespace' );
3428                         // From here we want to do checks on a file object, so if we can't
3429                         // create one, we must return.
3430                         return $errors;
3431                 }
3432
3433                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is allowed below here
3434
3435                 $destFile = wfLocalFile( $nt );
3436                 if ( !$wgUser->isAllowed( 'reupload-shared' ) && !$destFile->exists() && wfFindFile( $nt ) ) {
3437                         $errors[] = array( 'file-exists-sharedrepo' );
3438                 }
3439
3440                 return $errors;
3441         }
3442
3443         /**
3444          * Move a title to a new location
3445          *
3446          * @param $nt Title the new title
3447          * @param $auth Bool indicates whether $wgUser's permissions
3448          *  should be checked
3449          * @param $reason String the reason for the move
3450          * @param $createRedirect Bool Whether to create a redirect from the old title to the new title.
3451          *  Ignored if the user doesn't have the suppressredirect right.
3452          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3453          */
3454         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
3455                 global $wgUser;
3456                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
3457                 if ( is_array( $err ) ) {
3458                         // Auto-block user's IP if the account was "hard" blocked
3459                         $wgUser->spreadAnyEditBlock();
3460                         return $err;
3461                 }
3462
3463                 // If it is a file, move it first.
3464                 // It is done before all other moving stuff is done because it's hard to revert.
3465                 $dbw = wfGetDB( DB_MASTER );
3466                 if ( $this->getNamespace() == NS_FILE ) {
3467                         $file = wfLocalFile( $this );
3468                         if ( $file->exists() ) {
3469                                 $status = $file->move( $nt );
3470                                 if ( !$status->isOk() ) {
3471                                         return $status->getErrorsArray();
3472                                 }
3473                         }
3474                         // Clear RepoGroup process cache
3475                         RepoGroup::singleton()->clearCache( $this );
3476                         RepoGroup::singleton()->clearCache( $nt ); # clear false negative cache
3477                 }
3478
3479                 $dbw->begin( __METHOD__ ); # If $file was a LocalFile, its transaction would have closed our own.
3480                 $pageid = $this->getArticleID( self::GAID_FOR_UPDATE );
3481                 $protected = $this->isProtected();
3482
3483                 // Do the actual move
3484                 $err = $this->moveToInternal( $nt, $reason, $createRedirect );
3485                 if ( is_array( $err ) ) {
3486                         # @todo FIXME: What about the File we have already moved?
3487                         $dbw->rollback( __METHOD__ );
3488                         return $err;
3489                 }
3490
3491                 // Refresh the sortkey for this row.  Be careful to avoid resetting
3492                 // cl_timestamp, which may disturb time-based lists on some sites.
3493                 $prefixes = $dbw->select(
3494                         'categorylinks',
3495                         array( 'cl_sortkey_prefix', 'cl_to' ),
3496                         array( 'cl_from' => $pageid ),
3497                         __METHOD__
3498                 );
3499                 foreach ( $prefixes as $prefixRow ) {
3500                         $prefix = $prefixRow->cl_sortkey_prefix;
3501                         $catTo = $prefixRow->cl_to;
3502                         $dbw->update( 'categorylinks',
3503                                 array(
3504                                         'cl_sortkey' => Collation::singleton()->getSortKey(
3505                                                 $nt->getCategorySortkey( $prefix ) ),
3506                                         'cl_timestamp=cl_timestamp' ),
3507                                 array(
3508                                         'cl_from' => $pageid,
3509                                         'cl_to' => $catTo ),
3510                                 __METHOD__
3511                         );
3512                 }
3513
3514                 $redirid = $this->getArticleID();
3515
3516                 if ( $protected ) {
3517                         # Protect the redirect title as the title used to be...
3518                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
3519                                 array(
3520                                         'pr_page'    => $redirid,
3521                                         'pr_type'    => 'pr_type',
3522                                         'pr_level'   => 'pr_level',
3523                                         'pr_cascade' => 'pr_cascade',
3524                                         'pr_user'    => 'pr_user',
3525                                         'pr_expiry'  => 'pr_expiry'
3526                                 ),
3527                                 array( 'pr_page' => $pageid ),
3528                                 __METHOD__,
3529                                 array( 'IGNORE' )
3530                         );
3531                         # Update the protection log
3532                         $log = new LogPage( 'protect' );
3533                         $comment = wfMsgForContent( 'prot_1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
3534                         if ( $reason ) {
3535                                 $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3536                         }
3537                         // @todo FIXME: $params?
3538                         $log->addEntry( 'move_prot', $nt, $comment, array( $this->getPrefixedText() ) );
3539                 }
3540
3541                 # Update watchlists
3542                 $oldnamespace = $this->getNamespace() & ~1;
3543                 $newnamespace = $nt->getNamespace() & ~1;
3544                 $oldtitle = $this->getDBkey();
3545                 $newtitle = $nt->getDBkey();
3546
3547                 if ( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
3548                         WatchedItem::duplicateEntries( $this, $nt );
3549                 }
3550
3551                 $dbw->commit( __METHOD__ );
3552
3553                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3554                 return true;
3555         }
3556
3557         /**
3558          * Move page to a title which is either a redirect to the
3559          * source page or nonexistent
3560          *
3561          * @param $nt Title the page to move to, which should be a redirect or nonexistent
3562          * @param $reason String The reason for the move
3563          * @param $createRedirect Bool Whether to leave a redirect at the old title.  Ignored
3564          *   if the user doesn't have the suppressredirect right
3565          */
3566         private function moveToInternal( &$nt, $reason = '', $createRedirect = true ) {
3567                 global $wgUser, $wgContLang;
3568
3569                 if ( $nt->exists() ) {
3570                         $moveOverRedirect = true;
3571                         $logType = 'move_redir';
3572                 } else {
3573                         $moveOverRedirect = false;
3574                         $logType = 'move';
3575                 }
3576
3577                 $redirectSuppressed = !$createRedirect && $wgUser->isAllowed( 'suppressredirect' );
3578
3579                 $logEntry = new ManualLogEntry( 'move', $logType );
3580                 $logEntry->setPerformer( $wgUser );
3581                 $logEntry->setTarget( $this );
3582                 $logEntry->setComment( $reason );
3583                 $logEntry->setParameters( array(
3584                         '4::target' => $nt->getPrefixedText(),
3585                         '5::noredir' => $redirectSuppressed ? '1': '0',
3586                 ) );
3587
3588                 $formatter = LogFormatter::newFromEntry( $logEntry );
3589                 $formatter->setContext( RequestContext::newExtraneousContext( $this ) );
3590                 $comment = $formatter->getPlainActionText();
3591                 if ( $reason ) {
3592                         $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3593                 }
3594                 # Truncate for whole multibyte characters.
3595                 $comment = $wgContLang->truncate( $comment, 255 );
3596
3597                 $oldid = $this->getArticleID();
3598
3599                 $dbw = wfGetDB( DB_MASTER );
3600
3601                 $newpage = WikiPage::factory( $nt );
3602
3603                 if ( $moveOverRedirect ) {
3604                         $newid = $nt->getArticleID();
3605
3606                         # Delete the old redirect. We don't save it to history since
3607                         # by definition if we've got here it's rather uninteresting.
3608                         # We have to remove it so that the next step doesn't trigger
3609                         # a conflict on the unique namespace+title index...
3610                         $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3611
3612                         $newpage->doDeleteUpdates( $newid );
3613                 }
3614
3615                 # Save a null revision in the page's history notifying of the move
3616                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3617                 if ( !is_object( $nullRevision ) ) {
3618                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3619                 }
3620                 $nullRevId = $nullRevision->insertOn( $dbw );
3621
3622                 # Change the name of the target page:
3623                 $dbw->update( 'page',
3624                         /* SET */ array(
3625                                 'page_namespace' => $nt->getNamespace(),
3626                                 'page_title'     => $nt->getDBkey(),
3627                         ),
3628                         /* WHERE */ array( 'page_id' => $oldid ),
3629                         __METHOD__
3630                 );
3631
3632                 $this->resetArticleID( 0 );
3633                 $nt->resetArticleID( $oldid );
3634
3635                 $newpage->updateRevisionOn( $dbw, $nullRevision );
3636
3637                 wfRunHooks( 'NewRevisionFromEditComplete',
3638                         array( $newpage, $nullRevision, $nullRevision->getParentId(), $wgUser ) );
3639
3640                 $newpage->doEditUpdates( $nullRevision, $wgUser, array( 'changed' => false ) );
3641
3642                 if ( !$moveOverRedirect ) {
3643                         WikiPage::onArticleCreate( $nt );
3644                 }
3645
3646                 # Recreate the redirect, this time in the other direction.
3647                 if ( $redirectSuppressed ) {
3648                         WikiPage::onArticleDelete( $this );
3649                 } else {
3650                         $mwRedir = MagicWord::get( 'redirect' );
3651                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3652                         $redirectArticle = WikiPage::factory( $this );
3653                         $newid = $redirectArticle->insertOn( $dbw );
3654                         if ( $newid ) { // sanity
3655                                 $redirectRevision = new Revision( array(
3656                                         'page'    => $newid,
3657                                         'comment' => $comment,
3658                                         'text'    => $redirectText ) );
3659                                 $redirectRevision->insertOn( $dbw );
3660                                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3661
3662                                 wfRunHooks( 'NewRevisionFromEditComplete',
3663                                         array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3664
3665                                 $redirectArticle->doEditUpdates( $redirectRevision, $wgUser, array( 'created' => true ) );
3666                         }
3667                 }
3668
3669                 # Log the move
3670                 $logid = $logEntry->insert();
3671                 $logEntry->publish( $logid );
3672         }
3673
3674         /**
3675          * Move this page's subpages to be subpages of $nt
3676          *
3677          * @param $nt Title Move target
3678          * @param $auth bool Whether $wgUser's permissions should be checked
3679          * @param $reason string The reason for the move
3680          * @param $createRedirect bool Whether to create redirects from the old subpages to
3681          *     the new ones Ignored if the user doesn't have the 'suppressredirect' right
3682          * @return mixed array with old page titles as keys, and strings (new page titles) or
3683          *     arrays (errors) as values, or an error array with numeric indices if no pages
3684          *     were moved
3685          */
3686         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3687                 global $wgMaximumMovedPages;
3688                 // Check permissions
3689                 if ( !$this->userCan( 'move-subpages' ) ) {
3690                         return array( 'cant-move-subpages' );
3691                 }
3692                 // Do the source and target namespaces support subpages?
3693                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
3694                         return array( 'namespace-nosubpages',
3695                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3696                 }
3697                 if ( !MWNamespace::hasSubpages( $nt->getNamespace() ) ) {
3698                         return array( 'namespace-nosubpages',
3699                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3700                 }
3701
3702                 $subpages = $this->getSubpages( $wgMaximumMovedPages + 1 );
3703                 $retval = array();
3704                 $count = 0;
3705                 foreach ( $subpages as $oldSubpage ) {
3706                         $count++;
3707                         if ( $count > $wgMaximumMovedPages ) {
3708                                 $retval[$oldSubpage->getPrefixedTitle()] =
3709                                                 array( 'movepage-max-pages',
3710                                                         $wgMaximumMovedPages );
3711                                 break;
3712                         }
3713
3714                         // We don't know whether this function was called before
3715                         // or after moving the root page, so check both
3716                         // $this and $nt
3717                         if ( $oldSubpage->getArticleId() == $this->getArticleId() ||
3718                                         $oldSubpage->getArticleID() == $nt->getArticleId() )
3719                         {
3720                                 // When moving a page to a subpage of itself,
3721                                 // don't move it twice
3722                                 continue;
3723                         }
3724                         $newPageName = preg_replace(
3725                                         '#^' . preg_quote( $this->getDBkey(), '#' ) . '#',
3726                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3727                                         $oldSubpage->getDBkey() );
3728                         if ( $oldSubpage->isTalkPage() ) {
3729                                 $newNs = $nt->getTalkPage()->getNamespace();
3730                         } else {
3731                                 $newNs = $nt->getSubjectPage()->getNamespace();
3732                         }
3733                         # Bug 14385: we need makeTitleSafe because the new page names may
3734                         # be longer than 255 characters.
3735                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3736
3737                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3738                         if ( $success === true ) {
3739                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3740                         } else {
3741                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3742                         }
3743                 }
3744                 return $retval;
3745         }
3746
3747         /**
3748          * Checks if this page is just a one-rev redirect.
3749          * Adds lock, so don't use just for light purposes.
3750          *
3751          * @return Bool
3752          */
3753         public function isSingleRevRedirect() {
3754                 $dbw = wfGetDB( DB_MASTER );
3755                 # Is it a redirect?
3756                 $row = $dbw->selectRow( 'page',
3757                         array( 'page_is_redirect', 'page_latest', 'page_id' ),
3758                         $this->pageCond(),
3759                         __METHOD__,
3760                         array( 'FOR UPDATE' )
3761                 );
3762                 # Cache some fields we may want
3763                 $this->mArticleID = $row ? intval( $row->page_id ) : 0;
3764                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3765                 $this->mLatestID = $row ? intval( $row->page_latest ) : false;
3766                 if ( !$this->mRedirect ) {
3767                         return false;
3768                 }
3769                 # Does the article have a history?
3770                 $row = $dbw->selectField( array( 'page', 'revision' ),
3771                         'rev_id',
3772                         array( 'page_namespace' => $this->getNamespace(),
3773                                 'page_title' => $this->getDBkey(),
3774                                 'page_id=rev_page',
3775                                 'page_latest != rev_id'
3776                         ),
3777                         __METHOD__,
3778                         array( 'FOR UPDATE' )
3779                 );
3780                 # Return true if there was no history
3781                 return ( $row === false );
3782         }
3783
3784         /**
3785          * Checks if $this can be moved to a given Title
3786          * - Selects for update, so don't call it unless you mean business
3787          *
3788          * @param $nt Title the new title to check
3789          * @return Bool
3790          */
3791         public function isValidMoveTarget( $nt ) {
3792                 # Is it an existing file?
3793                 if ( $nt->getNamespace() == NS_FILE ) {
3794                         $file = wfLocalFile( $nt );
3795                         if ( $file->exists() ) {
3796                                 wfDebug( __METHOD__ . ": file exists\n" );
3797                                 return false;
3798                         }
3799                 }
3800                 # Is it a redirect with no history?
3801                 if ( !$nt->isSingleRevRedirect() ) {
3802                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3803                         return false;
3804                 }
3805                 # Get the article text
3806                 $rev = Revision::newFromTitle( $nt );
3807                 if( !is_object( $rev ) ){
3808                         return false;
3809                 }
3810                 $text = $rev->getText();
3811                 # Does the redirect point to the source?
3812                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3813                 $m = array();
3814                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
3815                         $redirTitle = Title::newFromText( $m[1] );
3816                         if ( !is_object( $redirTitle ) ||
3817                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3818                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
3819                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3820                                 return false;
3821                         }
3822                 } else {
3823                         # Fail safe
3824                         wfDebug( __METHOD__ . ": failsafe\n" );
3825                         return false;
3826                 }
3827                 return true;
3828         }
3829
3830         /**
3831          * Get categories to which this Title belongs and return an array of
3832          * categories' names.
3833          *
3834          * @return Array of parents in the form:
3835          *        $parent => $currentarticle
3836          */
3837         public function getParentCategories() {
3838                 global $wgContLang;
3839
3840                 $data = array();
3841
3842                 $titleKey = $this->getArticleId();
3843
3844                 if ( $titleKey === 0 ) {
3845                         return $data;
3846                 }
3847
3848                 $dbr = wfGetDB( DB_SLAVE );
3849
3850                 $res = $dbr->select( 'categorylinks', '*',
3851                         array(
3852                                 'cl_from' => $titleKey,
3853                         ),
3854                         __METHOD__,
3855                         array()
3856                 );
3857
3858                 if ( $dbr->numRows( $res ) > 0 ) {
3859                         foreach ( $res as $row ) {
3860                                 // $data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
3861                                 $data[$wgContLang->getNSText( NS_CATEGORY ) . ':' . $row->cl_to] = $this->getFullText();
3862                         }
3863                 }
3864                 return $data;
3865         }
3866
3867         /**
3868          * Get a tree of parent categories
3869          *
3870          * @param $children Array with the children in the keys, to check for circular refs
3871          * @return Array Tree of parent categories
3872          */
3873         public function getParentCategoryTree( $children = array() ) {
3874                 $stack = array();
3875                 $parents = $this->getParentCategories();
3876
3877                 if ( $parents ) {
3878                         foreach ( $parents as $parent => $current ) {
3879                                 if ( array_key_exists( $parent, $children ) ) {
3880                                         # Circular reference
3881                                         $stack[$parent] = array();
3882                                 } else {
3883                                         $nt = Title::newFromText( $parent );
3884                                         if ( $nt ) {
3885                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array( $parent => 1 ) );
3886                                         }
3887                                 }
3888                         }
3889                 }
3890
3891                 return $stack;
3892         }
3893
3894         /**
3895          * Get an associative array for selecting this title from
3896          * the "page" table
3897          *
3898          * @return Array suitable for the $where parameter of DB::select()
3899          */
3900         public function pageCond() {
3901                 if ( $this->mArticleID > 0 ) {
3902                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
3903                         return array( 'page_id' => $this->mArticleID );
3904                 } else {
3905                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
3906                 }
3907         }
3908
3909         /**
3910          * Get the revision ID of the previous revision
3911          *
3912          * @param $revId Int Revision ID. Get the revision that was before this one.
3913          * @param $flags Int Title::GAID_FOR_UPDATE
3914          * @return Int|Bool Old revision ID, or FALSE if none exists
3915          */
3916         public function getPreviousRevisionID( $revId, $flags = 0 ) {
3917                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3918                 return $db->selectField( 'revision', 'rev_id',
3919                         array(
3920                                 'rev_page' => $this->getArticleId( $flags ),
3921                                 'rev_id < ' . intval( $revId )
3922                         ),
3923                         __METHOD__,
3924                         array( 'ORDER BY' => 'rev_id DESC' )
3925                 );
3926         }
3927
3928         /**
3929          * Get the revision ID of the next revision
3930          *
3931          * @param $revId Int Revision ID. Get the revision that was after this one.
3932          * @param $flags Int Title::GAID_FOR_UPDATE
3933          * @return Int|Bool Next revision ID, or FALSE if none exists
3934          */
3935         public function getNextRevisionID( $revId, $flags = 0 ) {
3936                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3937                 return $db->selectField( 'revision', 'rev_id',
3938                         array(
3939                                 'rev_page' => $this->getArticleId( $flags ),
3940                                 'rev_id > ' . intval( $revId )
3941                         ),
3942                         __METHOD__,
3943                         array( 'ORDER BY' => 'rev_id' )
3944                 );
3945         }
3946
3947         /**
3948          * Get the first revision of the page
3949          *
3950          * @param $flags Int Title::GAID_FOR_UPDATE
3951          * @return Revision|Null if page doesn't exist
3952          */
3953         public function getFirstRevision( $flags = 0 ) {
3954                 $pageId = $this->getArticleId( $flags );
3955                 if ( $pageId ) {
3956                         $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3957                         $row = $db->selectRow( 'revision', '*',
3958                                 array( 'rev_page' => $pageId ),
3959                                 __METHOD__,
3960                                 array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
3961                         );
3962                         if ( $row ) {
3963                                 return new Revision( $row );
3964                         }
3965                 }
3966                 return null;
3967         }
3968
3969         /**
3970          * Get the oldest revision timestamp of this page
3971          *
3972          * @param $flags Int Title::GAID_FOR_UPDATE
3973          * @return String: MW timestamp
3974          */
3975         public function getEarliestRevTime( $flags = 0 ) {
3976                 $rev = $this->getFirstRevision( $flags );
3977                 return $rev ? $rev->getTimestamp() : null;
3978         }
3979
3980         /**
3981          * Check if this is a new page
3982          *
3983          * @return bool
3984          */
3985         public function isNewPage() {
3986                 $dbr = wfGetDB( DB_SLAVE );
3987                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
3988         }
3989
3990         /**
3991          * Check whether the number of revisions of this page surpasses $wgDeleteRevisionsLimit
3992          *
3993          * @return bool
3994          */
3995         public function isBigDeletion() {
3996                 global $wgDeleteRevisionsLimit;
3997
3998                 if ( !$wgDeleteRevisionsLimit ) {
3999                         return false;
4000                 }
4001
4002                 $revCount = $this->estimateRevisionCount();
4003                 return $revCount > $wgDeleteRevisionsLimit;
4004         }
4005
4006         /**
4007          * Get the  approximate revision count of this page.
4008          *
4009          * @return int
4010          */
4011         public function estimateRevisionCount() {
4012                 if ( !$this->exists() ) {
4013                         return 0;
4014                 }
4015
4016                 if ( $this->mEstimateRevisions === null ) {
4017                         $dbr = wfGetDB( DB_SLAVE );
4018                         $this->mEstimateRevisions = $dbr->estimateRowCount( 'revision', '*',
4019                                 array( 'rev_page' => $this->getArticleId() ), __METHOD__ );
4020                 }
4021
4022                 return $this->mEstimateRevisions;
4023         }
4024
4025         /**
4026          * Get the number of revisions between the given revision.
4027          * Used for diffs and other things that really need it.
4028          *
4029          * @param $old int|Revision Old revision or rev ID (first before range)
4030          * @param $new int|Revision New revision or rev ID (first after range)
4031          * @return Int Number of revisions between these revisions.
4032          */
4033         public function countRevisionsBetween( $old, $new ) {
4034                 if ( !( $old instanceof Revision ) ) {
4035                         $old = Revision::newFromTitle( $this, (int)$old );
4036                 }
4037                 if ( !( $new instanceof Revision ) ) {
4038                         $new = Revision::newFromTitle( $this, (int)$new );
4039                 }
4040                 if ( !$old || !$new ) {
4041                         return 0; // nothing to compare
4042                 }
4043                 $dbr = wfGetDB( DB_SLAVE );
4044                 return (int)$dbr->selectField( 'revision', 'count(*)',
4045                         array(
4046                                 'rev_page' => $this->getArticleId(),
4047                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4048                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4049                         ),
4050                         __METHOD__
4051                 );
4052         }
4053
4054         /**
4055          * Get the number of authors between the given revision IDs.
4056          * Used for diffs and other things that really need it.
4057          *
4058          * @param $old int|Revision Old revision or rev ID (first before range)
4059          * @param $new int|Revision New revision or rev ID (first after range)
4060          * @param $limit Int Maximum number of authors
4061          * @return Int Number of revision authors between these revisions.
4062          */
4063         public function countAuthorsBetween( $old, $new, $limit ) {
4064                 if ( !( $old instanceof Revision ) ) {
4065                         $old = Revision::newFromTitle( $this, (int)$old );
4066                 }
4067                 if ( !( $new instanceof Revision ) ) {
4068                         $new = Revision::newFromTitle( $this, (int)$new );
4069                 }
4070                 if ( !$old || !$new ) {
4071                         return 0; // nothing to compare
4072                 }
4073                 $dbr = wfGetDB( DB_SLAVE );
4074                 $res = $dbr->select( 'revision', 'DISTINCT rev_user_text',
4075                         array(
4076                                 'rev_page' => $this->getArticleID(),
4077                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4078                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4079                         ), __METHOD__,
4080                         array( 'LIMIT' => $limit + 1 ) // add one so caller knows it was truncated
4081                 );
4082                 return (int)$dbr->numRows( $res );
4083         }
4084
4085         /**
4086          * Compare with another title.
4087          *
4088          * @param $title Title
4089          * @return Bool
4090          */
4091         public function equals( Title $title ) {
4092                 // Note: === is necessary for proper matching of number-like titles.
4093                 return $this->getInterwiki() === $title->getInterwiki()
4094                         && $this->getNamespace() == $title->getNamespace()
4095                         && $this->getDBkey() === $title->getDBkey();
4096         }
4097
4098         /**
4099          * Check if this title is a subpage of another title
4100          *
4101          * @param $title Title
4102          * @return Bool
4103          */
4104         public function isSubpageOf( Title $title ) {
4105                 return $this->getInterwiki() === $title->getInterwiki()
4106                         && $this->getNamespace() == $title->getNamespace()
4107                         && strpos( $this->getDBkey(), $title->getDBkey() . '/' ) === 0;
4108         }
4109
4110         /**
4111          * Check if page exists.  For historical reasons, this function simply
4112          * checks for the existence of the title in the page table, and will
4113          * thus return false for interwiki links, special pages and the like.
4114          * If you want to know if a title can be meaningfully viewed, you should
4115          * probably call the isKnown() method instead.
4116          *
4117          * @return Bool
4118          */
4119         public function exists() {
4120                 return $this->getArticleId() != 0;
4121         }
4122
4123         /**
4124          * Should links to this title be shown as potentially viewable (i.e. as
4125          * "bluelinks"), even if there's no record by this title in the page
4126          * table?
4127          *
4128          * This function is semi-deprecated for public use, as well as somewhat
4129          * misleadingly named.  You probably just want to call isKnown(), which
4130          * calls this function internally.
4131          *
4132          * (ISSUE: Most of these checks are cheap, but the file existence check
4133          * can potentially be quite expensive.  Including it here fixes a lot of
4134          * existing code, but we might want to add an optional parameter to skip
4135          * it and any other expensive checks.)
4136          *
4137          * @return Bool
4138          */
4139         public function isAlwaysKnown() {
4140                 $isKnown = null;
4141
4142                 /**
4143                  * Allows overriding default behaviour for determining if a page exists.
4144                  * If $isKnown is kept as null, regular checks happen. If it's
4145                  * a boolean, this value is returned by the isKnown method.
4146                  *
4147                  * @since 1.20
4148                  *
4149                  * @param Title $title
4150                  * @param boolean|null $isKnown
4151                  */
4152                 wfRunHooks( 'TitleIsAlwaysKnown', array( $this, &$isKnown ) );
4153
4154                 if ( !is_null( $isKnown ) ) {
4155                         return $isKnown;
4156                 }
4157
4158                 if ( $this->mInterwiki != '' ) {
4159                         return true;  // any interwiki link might be viewable, for all we know
4160                 }
4161
4162                 switch( $this->mNamespace ) {
4163                         case NS_MEDIA:
4164                         case NS_FILE:
4165                                 // file exists, possibly in a foreign repo
4166                                 return (bool)wfFindFile( $this );
4167                         case NS_SPECIAL:
4168                                 // valid special page
4169                                 return SpecialPageFactory::exists( $this->getDBkey() );
4170                         case NS_MAIN:
4171                                 // selflink, possibly with fragment
4172                                 return $this->mDbkeyform == '';
4173                         case NS_MEDIAWIKI:
4174                                 // known system message
4175                                 return $this->hasSourceText() !== false;
4176                         default:
4177                                 return false;
4178                 }
4179         }
4180
4181         /**
4182          * Does this title refer to a page that can (or might) be meaningfully
4183          * viewed?  In particular, this function may be used to determine if
4184          * links to the title should be rendered as "bluelinks" (as opposed to
4185          * "redlinks" to non-existent pages).
4186          * Adding something else to this function will cause inconsistency
4187          * since LinkHolderArray calls isAlwaysKnown() and does its own
4188          * page existence check.
4189          *
4190          * @return Bool
4191          */
4192         public function isKnown() {
4193                 return $this->isAlwaysKnown() || $this->exists();
4194         }
4195
4196         /**
4197          * Does this page have source text?
4198          *
4199          * @return Boolean
4200          */
4201         public function hasSourceText() {
4202                 if ( $this->exists() ) {
4203                         return true;
4204                 }
4205
4206                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
4207                         // If the page doesn't exist but is a known system message, default
4208                         // message content will be displayed, same for language subpages-
4209                         // Use always content language to avoid loading hundreds of languages
4210                         // to get the link color.
4211                         global $wgContLang;
4212                         list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4213                         $message = wfMessage( $name )->inLanguage( $wgContLang )->useDatabase( false );
4214                         return $message->exists();
4215                 }
4216
4217                 return false;
4218         }
4219
4220         /**
4221          * Get the default message text or false if the message doesn't exist
4222          *
4223          * @return String or false
4224          */
4225         public function getDefaultMessageText() {
4226                 global $wgContLang;
4227
4228                 if ( $this->getNamespace() != NS_MEDIAWIKI ) { // Just in case
4229                         return false;
4230                 }
4231
4232                 list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4233                 $message = wfMessage( $name )->inLanguage( $lang )->useDatabase( false );
4234
4235                 if ( $message->exists() ) {
4236                         return $message->plain();
4237                 } else {
4238                         return false;
4239                 }
4240         }
4241
4242         /**
4243          * Updates page_touched for this page; called from LinksUpdate.php
4244          *
4245          * @return Bool true if the update succeded
4246          */
4247         public function invalidateCache() {
4248                 if ( wfReadOnly() ) {
4249                         return false;
4250                 }
4251                 $dbw = wfGetDB( DB_MASTER );
4252                 $success = $dbw->update(
4253                         'page',
4254                         array( 'page_touched' => $dbw->timestamp() ),
4255                         $this->pageCond(),
4256                         __METHOD__
4257                 );
4258                 HTMLFileCache::clearFileCache( $this );
4259                 return $success;
4260         }
4261
4262         /**
4263          * Update page_touched timestamps and send squid purge messages for
4264          * pages linking to this title. May be sent to the job queue depending
4265          * on the number of links. Typically called on create and delete.
4266          */
4267         public function touchLinks() {
4268                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
4269                 $u->doUpdate();
4270
4271                 if ( $this->getNamespace() == NS_CATEGORY ) {
4272                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
4273                         $u->doUpdate();
4274                 }
4275         }
4276
4277         /**
4278          * Get the last touched timestamp
4279          *
4280          * @param $db DatabaseBase: optional db
4281          * @return String last-touched timestamp
4282          */
4283         public function getTouched( $db = null ) {
4284                 $db = isset( $db ) ? $db : wfGetDB( DB_SLAVE );
4285                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
4286                 return $touched;
4287         }
4288
4289         /**
4290          * Get the timestamp when this page was updated since the user last saw it.
4291          *
4292          * @param $user User
4293          * @return String|Null
4294          */
4295         public function getNotificationTimestamp( $user = null ) {
4296                 global $wgUser, $wgShowUpdatedMarker;
4297                 // Assume current user if none given
4298                 if ( !$user ) {
4299                         $user = $wgUser;
4300                 }
4301                 // Check cache first
4302                 $uid = $user->getId();
4303                 // avoid isset here, as it'll return false for null entries
4304                 if ( array_key_exists( $uid, $this->mNotificationTimestamp ) ) {
4305                         return $this->mNotificationTimestamp[$uid];
4306                 }
4307                 if ( !$uid || !$wgShowUpdatedMarker ) {
4308                         return $this->mNotificationTimestamp[$uid] = false;
4309                 }
4310                 // Don't cache too much!
4311                 if ( count( $this->mNotificationTimestamp ) >= self::CACHE_MAX ) {
4312                         $this->mNotificationTimestamp = array();
4313                 }
4314                 $dbr = wfGetDB( DB_SLAVE );
4315                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
4316                         'wl_notificationtimestamp',
4317                         array( 'wl_namespace' => $this->getNamespace(),
4318                                 'wl_title' => $this->getDBkey(),
4319                                 'wl_user' => $user->getId()
4320                         ),
4321                         __METHOD__
4322                 );
4323                 return $this->mNotificationTimestamp[$uid];
4324         }
4325
4326         /**
4327          * Generate strings used for xml 'id' names in monobook tabs
4328          *
4329          * @param $prepend string defaults to 'nstab-'
4330          * @return String XML 'id' name
4331          */
4332         public function getNamespaceKey( $prepend = 'nstab-' ) {
4333                 global $wgContLang;
4334                 // Gets the subject namespace if this title
4335                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
4336                 // Checks if cononical namespace name exists for namespace
4337                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
4338                         // Uses canonical namespace name
4339                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
4340                 } else {
4341                         // Uses text of namespace
4342                         $namespaceKey = $this->getSubjectNsText();
4343                 }
4344                 // Makes namespace key lowercase
4345                 $namespaceKey = $wgContLang->lc( $namespaceKey );
4346                 // Uses main
4347                 if ( $namespaceKey == '' ) {
4348                         $namespaceKey = 'main';
4349                 }
4350                 // Changes file to image for backwards compatibility
4351                 if ( $namespaceKey == 'file' ) {
4352                         $namespaceKey = 'image';
4353                 }
4354                 return $prepend . $namespaceKey;
4355         }
4356
4357         /**
4358          * Get all extant redirects to this Title
4359          *
4360          * @param $ns Int|Null Single namespace to consider; NULL to consider all namespaces
4361          * @return Array of Title redirects to this title
4362          */
4363         public function getRedirectsHere( $ns = null ) {
4364                 $redirs = array();
4365
4366                 $dbr = wfGetDB( DB_SLAVE );
4367                 $where = array(
4368                         'rd_namespace' => $this->getNamespace(),
4369                         'rd_title' => $this->getDBkey(),
4370                         'rd_from = page_id'
4371                 );
4372                 if ( !is_null( $ns ) ) {
4373                         $where['page_namespace'] = $ns;
4374                 }
4375
4376                 $res = $dbr->select(
4377                         array( 'redirect', 'page' ),
4378                         array( 'page_namespace', 'page_title' ),
4379                         $where,
4380                         __METHOD__
4381                 );
4382
4383                 foreach ( $res as $row ) {
4384                         $redirs[] = self::newFromRow( $row );
4385                 }
4386                 return $redirs;
4387         }
4388
4389         /**
4390          * Check if this Title is a valid redirect target
4391          *
4392          * @return Bool
4393          */
4394         public function isValidRedirectTarget() {
4395                 global $wgInvalidRedirectTargets;
4396
4397                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
4398                 if ( $this->isSpecial( 'Userlogout' ) ) {
4399                         return false;
4400                 }
4401
4402                 foreach ( $wgInvalidRedirectTargets as $target ) {
4403                         if ( $this->isSpecial( $target ) ) {
4404                                 return false;
4405                         }
4406                 }
4407
4408                 return true;
4409         }
4410
4411         /**
4412          * Get a backlink cache object
4413          *
4414          * @return BacklinkCache
4415          */
4416         function getBacklinkCache() {
4417                 if ( is_null( $this->mBacklinkCache ) ) {
4418                         $this->mBacklinkCache = new BacklinkCache( $this );
4419                 }
4420                 return $this->mBacklinkCache;
4421         }
4422
4423         /**
4424          * Whether the magic words __INDEX__ and __NOINDEX__ function for  this page.
4425          *
4426          * @return Boolean
4427          */
4428         public function canUseNoindex() {
4429                 global $wgContentNamespaces, $wgExemptFromUserRobotsControl;
4430
4431                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
4432                         ? $wgContentNamespaces
4433                         : $wgExemptFromUserRobotsControl;
4434
4435                 return !in_array( $this->mNamespace, $bannedNamespaces );
4436
4437         }
4438
4439         /**
4440          * Returns the raw sort key to be used for categories, with the specified
4441          * prefix.  This will be fed to Collation::getSortKey() to get a
4442          * binary sortkey that can be used for actual sorting.
4443          *
4444          * @param $prefix string The prefix to be used, specified using
4445          *   {{defaultsort:}} or like [[Category:Foo|prefix]].  Empty for no
4446          *   prefix.
4447          * @return string
4448          */
4449         public function getCategorySortkey( $prefix = '' ) {
4450                 $unprefixed = $this->getText();
4451
4452                 // Anything that uses this hook should only depend
4453                 // on the Title object passed in, and should probably
4454                 // tell the users to run updateCollations.php --force
4455                 // in order to re-sort existing category relations.
4456                 wfRunHooks( 'GetDefaultSortkey', array( $this, &$unprefixed ) );
4457                 if ( $prefix !== '' ) {
4458                         # Separate with a line feed, so the unprefixed part is only used as
4459                         # a tiebreaker when two pages have the exact same prefix.
4460                         # In UCA, tab is the only character that can sort above LF
4461                         # so we strip both of them from the original prefix.
4462                         $prefix = strtr( $prefix, "\n\t", '  ' );
4463                         return "$prefix\n$unprefixed";
4464                 }
4465                 return $unprefixed;
4466         }
4467
4468         /**
4469          * Get the language in which the content of this page is written.
4470          * Defaults to $wgContLang, but in certain cases it can be e.g.
4471          * $wgLang (such as special pages, which are in the user language).
4472          *
4473          * @since 1.18
4474          * @return object Language
4475          */
4476         public function getPageLanguage() {
4477                 global $wgLang;
4478                 if ( $this->isSpecialPage() ) {
4479                         // special pages are in the user language
4480                         return $wgLang;
4481                 } elseif ( $this->isCssOrJsPage() || $this->isCssJsSubpage() ) {
4482                         // css/js should always be LTR and is, in fact, English
4483                         return wfGetLangObj( 'en' );
4484                 } elseif ( $this->getNamespace() == NS_MEDIAWIKI ) {
4485                         // Parse mediawiki messages with correct target language
4486                         list( /* $unused */, $lang ) = MessageCache::singleton()->figureMessage( $this->getText() );
4487                         return wfGetLangObj( $lang );
4488                 }
4489                 global $wgContLang;
4490                 // If nothing special, it should be in the wiki content language
4491                 $pageLang = $wgContLang;
4492                 // Hook at the end because we don't want to override the above stuff
4493                 wfRunHooks( 'PageContentLanguage', array( $this, &$pageLang, $wgLang ) );
4494                 return wfGetLangObj( $pageLang );
4495         }
4496 }