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         var $mHasSubpage;                 // /< Whether a page has any subpages
  87         // @}
  88
  89
  90         /**
  91          * Constructor
  92          */
  93         /*protected*/ function __construct() { }
  94
  95         /**
  96          * Create a new Title from a prefixed DB key
  97          *
  98          * @param $key String the database key, which has underscores
  99          *      instead of spaces, possibly including namespace and
 100          *      interwiki prefixes
 101          * @return Title, or NULL on an error
 102          */
 103         public static function newFromDBkey( $key ) {
 104                 $t = new Title();
 105                 $t->mDbkeyform = $key;
 106                 if ( $t->secureAndSplit() ) {
 107                         return $t;
 108                 } else {
 109                         return null;
 110                 }
 111         }
 112
 113         /**
 114          * Create a new Title from text, such as what one would find in a link. De-
 115          * codes any HTML entities in the text.
 116          *
 117          * @param $text String the link text; spaces, prefixes, and an
 118          *   initial ':' indicating the main namespace are accepted.
 119          * @param $defaultNamespace Int the namespace to use if none is speci-
 120          *   fied by a prefix.  If you want to force a specific namespace even if
 121          *   $text might begin with a namespace prefix, use makeTitle() or
 122          *   makeTitleSafe().
 123          * @throws MWException
 124          * @return Title|null - Title or null on an error.
 125          */
 126         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 127                 if ( is_object( $text ) ) {
 128                         throw new MWException( 'Title::newFromText given an object' );
 129                 }
 130
 131                 /**
 132                  * Wiki pages often contain multiple links to the same page.
 133                  * Title normalization and parsing can become expensive on
 134                  * pages with many links, so we can save a little time by
 135                  * caching them.
 136                  *
 137                  * In theory these are value objects and won't get changed...
 138                  */
 139                 if ( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 140                         return Title::$titleCache[$text];
 141                 }
 142
 143                 # Convert things like &eacute; &#257; or &#x3017; into normalized (bug 14952) text
 144                 $filteredText = Sanitizer::decodeCharReferencesAndNormalize( $text );
 145
 146                 $t = new Title();
 147                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 148                 $t->mDefaultNamespace = $defaultNamespace;
 149
 150                 static $cachedcount = 0 ;
 151                 if ( $t->secureAndSplit() ) {
 152                         if ( $defaultNamespace == NS_MAIN ) {
 153                                 if ( $cachedcount >= self::CACHE_MAX ) {
 154                                         # Avoid memory leaks on mass operations...
 155                                         Title::$titleCache = array();
 156                                         $cachedcount = 0;
 157                                 }
 158                                 $cachedcount++;
 159                                 Title::$titleCache[$text] =& $t;
 160                         }
 161                         return $t;
 162                 } else {
 163                         $ret = null;
 164                         return $ret;
 165                 }
 166         }
 167
 168         /**
 169          * THIS IS NOT THE FUNCTION YOU WANT. Use Title::newFromText().
 170          *
 171          * Example of wrong and broken code:
 172          * $title = Title::newFromURL( $wgRequest->getVal( 'title' ) );
 173          *
 174          * Example of right code:
 175          * $title = Title::newFromText( $wgRequest->getVal( 'title' ) );
 176          *
 177          * Create a new Title from URL-encoded text. Ensures that
 178          * the given title's length does not exceed the maximum.
 179          *
 180          * @param $url String the title, as might be taken from a URL
 181          * @return Title the new object, or NULL on an error
 182          */
 183         public static function newFromURL( $url ) {
 184                 $t = new Title();
 185
 186                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 187                 # but some URLs used it as a space replacement and they still come
 188                 # from some external search tools.
 189                 if ( strpos( self::legalChars(), '+' ) === false ) {
 190                         $url = str_replace( '+', ' ', $url );
 191                 }
 192
 193                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 194                 if ( $t->secureAndSplit() ) {
 195                         return $t;
 196                 } else {
 197                         return null;
 198                 }
 199         }
 200
 201         /**
 202          * Create a new Title from an article ID
 203          *
 204          * @param $id Int the page_id corresponding to the Title to create
 205          * @param $flags Int use Title::GAID_FOR_UPDATE to use master
 206          * @return Title the new object, or NULL on an error
 207          */
 208         public static function newFromID( $id, $flags = 0 ) {
 209                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
 210                 $row = $db->selectRow( 'page', '*', array( 'page_id' => $id ), __METHOD__ );
 211                 if ( $row !== false ) {
 212                         $title = Title::newFromRow( $row );
 213                 } else {
 214                         $title = null;
 215                 }
 216                 return $title;
 217         }
 218
 219         /**
 220          * Make an array of titles from an array of IDs
 221          *
 222          * @param $ids Array of Int Array of IDs
 223          * @return Array of Titles
 224          */
 225         public static function newFromIDs( $ids ) {
 226                 if ( !count( $ids ) ) {
 227                         return array();
 228                 }
 229                 $dbr = wfGetDB( DB_SLAVE );
 230
 231                 $res = $dbr->select(
 232                         'page',
 233                         array(
 234                                 'page_namespace', 'page_title', 'page_id',
 235                                 'page_len', 'page_is_redirect', 'page_latest',
 236                         ),
 237                         array( 'page_id' => $ids ),
 238                         __METHOD__
 239                 );
 240
 241                 $titles = array();
 242                 foreach ( $res as $row ) {
 243                         $titles[] = Title::newFromRow( $row );
 244                 }
 245                 return $titles;
 246         }
 247
 248         /**
 249          * Make a Title object from a DB row
 250          *
 251          * @param $row Object database row (needs at least page_title,page_namespace)
 252          * @return Title corresponding Title
 253          */
 254         public static function newFromRow( $row ) {
 255                 $t = self::makeTitle( $row->page_namespace, $row->page_title );
 256                 $t->loadFromRow( $row );
 257                 return $t;
 258         }
 259
 260         /**
 261          * Load Title object fields from a DB row.
 262          * If false is given, the title will be treated as non-existing.
 263          *
 264          * @param $row Object|bool database row
 265          */
 266         public function loadFromRow( $row ) {
 267                 if ( $row ) { // page found
 268                         if ( isset( $row->page_id ) )
 269                                 $this->mArticleID = (int)$row->page_id;
 270                         if ( isset( $row->page_len ) )
 271                                 $this->mLength = (int)$row->page_len;
 272                         if ( isset( $row->page_is_redirect ) )
 273                                 $this->mRedirect = (bool)$row->page_is_redirect;
 274                         if ( isset( $row->page_latest ) )
 275                                 $this->mLatestID = (int)$row->page_latest;
 276                 } else { // page not found
 277                         $this->mArticleID = 0;
 278                         $this->mLength = 0;
 279                         $this->mRedirect = false;
 280                         $this->mLatestID = 0;
 281                 }
 282         }
 283
 284         /**
 285          * Create a new Title from a namespace index and a DB key.
 286          * It's assumed that $ns and $title are *valid*, for instance when
 287          * they came directly from the database or a special page name.
 288          * For convenience, spaces are converted to underscores so that
 289          * eg user_text fields can be used directly.
 290          *
 291          * @param $ns Int the namespace of the article
 292          * @param $title String the unprefixed database key form
 293          * @param $fragment String the link fragment (after the "#")
 294          * @param $interwiki String the interwiki prefix
 295          * @return Title the new object
 296          */
 297         public static function &makeTitle( $ns, $title, $fragment = '', $interwiki = '' ) {
 298                 $t = new Title();
 299                 $t->mInterwiki = $interwiki;
 300                 $t->mFragment = $fragment;
 301                 $t->mNamespace = $ns = intval( $ns );
 302                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 303                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 304                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 305                 $t->mTextform = str_replace( '_', ' ', $title );
 306                 return $t;
 307         }
 308
 309         /**
 310          * Create a new Title from a namespace index and a DB key.
 311          * The parameters will be checked for validity, which is a bit slower
 312          * than makeTitle() but safer for user-provided data.
 313          *
 314          * @param $ns Int the namespace of the article
 315          * @param $title String database key form
 316          * @param $fragment String the link fragment (after the "#")
 317          * @param $interwiki String interwiki prefix
 318          * @return Title the new object, or NULL on an error
 319          */
 320         public static function makeTitleSafe( $ns, $title, $fragment = '', $interwiki = '' ) {
 321                 if ( !MWNamespace::exists( $ns ) ) {
 322                         return null;
 323                 }
 324
 325                 $t = new Title();
 326                 $t->mDbkeyform = Title::makeName( $ns, $title, $fragment, $interwiki );
 327                 if ( $t->secureAndSplit() ) {
 328                         return $t;
 329                 } else {
 330                         return null;
 331                 }
 332         }
 333
 334         /**
 335          * Create a new Title for the Main Page
 336          *
 337          * @return Title the new object
 338          */
 339         public static function newMainPage() {
 340                 $title = Title::newFromText( wfMsgForContent( 'mainpage' ) );
 341                 // Don't give fatal errors if the message is broken
 342                 if ( !$title ) {
 343                         $title = Title::newFromText( 'Main Page' );
 344                 }
 345                 return $title;
 346         }
 347
 348         /**
 349          * Extract a redirect destination from a string and return the
 350          * Title, or null if the text doesn't contain a valid redirect
 351          * This will only return the very next target, useful for
 352          * the redirect table and other checks that don't need full recursion
 353          *
 354          * @param $text String: Text with possible redirect
 355          * @return Title: The corresponding Title
 356          */
 357         public static function newFromRedirect( $text ) {
 358                 return self::newFromRedirectInternal( $text );
 359         }
 360
 361         /**
 362          * Extract a redirect destination from a string and return the
 363          * Title, or null if the text doesn't contain a valid redirect
 364          * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
 365          * in order to provide (hopefully) the Title of the final destination instead of another redirect
 366          *
 367          * @param $text String Text with possible redirect
 368          * @return Title
 369          */
 370         public static function newFromRedirectRecurse( $text ) {
 371                 $titles = self::newFromRedirectArray( $text );
 372                 return $titles ? array_pop( $titles ) : null;
 373         }
 374
 375         /**
 376          * Extract a redirect destination from a string and return an
 377          * array of Titles, or null if the text doesn't contain a valid redirect
 378          * The last element in the array is the final destination after all redirects
 379          * have been resolved (up to $wgMaxRedirects times)
 380          *
 381          * @param $text String Text with possible redirect
 382          * @return Array of Titles, with the destination last
 383          */
 384         public static function newFromRedirectArray( $text ) {
 385                 global $wgMaxRedirects;
 386                 $title = self::newFromRedirectInternal( $text );
 387                 if ( is_null( $title ) ) {
 388                         return null;
 389                 }
 390                 // recursive check to follow double redirects
 391                 $recurse = $wgMaxRedirects;
 392                 $titles = array( $title );
 393                 while ( --$recurse > 0 ) {
 394                         if ( $title->isRedirect() ) {
 395                                 $page = WikiPage::factory( $title );
 396                                 $newtitle = $page->getRedirectTarget();
 397                         } else {
 398                                 break;
 399                         }
 400                         // Redirects to some special pages are not permitted
 401                         if ( $newtitle instanceOf Title && $newtitle->isValidRedirectTarget() ) {
 402                                 // the new title passes the checks, so make that our current title so that further recursion can be checked
 403                                 $title = $newtitle;
 404                                 $titles[] = $newtitle;
 405                         } else {
 406                                 break;
 407                         }
 408                 }
 409                 return $titles;
 410         }
 411
 412         /**
 413          * Really extract the redirect destination
 414          * Do not call this function directly, use one of the newFromRedirect* functions above
 415          *
 416          * @param $text String Text with possible redirect
 417          * @return Title
 418          */
 419         protected static function newFromRedirectInternal( $text ) {
 420                 global $wgMaxRedirects;
 421                 if ( $wgMaxRedirects < 1 ) {
 422                         //redirects are disabled, so quit early
 423                         return null;
 424                 }
 425                 $redir = MagicWord::get( 'redirect' );
 426                 $text = trim( $text );
 427                 if ( $redir->matchStartAndRemove( $text ) ) {
 428                         // Extract the first link and see if it's usable
 429                         // Ensure that it really does come directly after #REDIRECT
 430                         // Some older redirects included a colon, so don't freak about that!
 431                         $m = array();
 432                         if ( preg_match( '!^\s*:?\s*\[{2}(.*?)(?:\|.*?)?\]{2}!', $text, $m ) ) {
 433                                 // Strip preceding colon used to "escape" categories, etc.
 434                                 // and URL-decode links
 435                                 if ( strpos( $m[1], '%' ) !== false ) {
 436                                         // Match behavior of inline link parsing here;
 437                                         $m[1] = rawurldecode( ltrim( $m[1], ':' ) );
 438                                 }
 439                                 $title = Title::newFromText( $m[1] );
 440                                 // If the title is a redirect to bad special pages or is invalid, return null
 441                                 if ( !$title instanceof Title || !$title->isValidRedirectTarget() ) {
 442                                         return null;
 443                                 }
 444                                 return $title;
 445                         }
 446                 }
 447                 return null;
 448         }
 449
 450         /**
 451          * Get the prefixed DB key associated with an ID
 452          *
 453          * @param $id Int the page_id of the article
 454          * @return Title an object representing the article, or NULL if no such article was found
 455          */
 456         public static function nameOf( $id ) {
 457                 $dbr = wfGetDB( DB_SLAVE );
 458
 459                 $s = $dbr->selectRow(
 460                         'page',
 461                         array( 'page_namespace', 'page_title' ),
 462                         array( 'page_id' => $id ),
 463                         __METHOD__
 464                 );
 465                 if ( $s === false ) {
 466                         return null;
 467                 }
 468
 469                 $n = self::makeName( $s->page_namespace, $s->page_title );
 470                 return $n;
 471         }
 472
 473         /**
 474          * Get a regex character class describing the legal characters in a link
 475          *
 476          * @return String the list of characters, not delimited
 477          */
 478         public static function legalChars() {
 479                 global $wgLegalTitleChars;
 480                 return $wgLegalTitleChars;
 481         }
 482
 483         /**
 484          * Returns a simple regex that will match on characters and sequences invalid in titles.
 485          * Note that this doesn't pick up many things that could be wrong with titles, but that
 486          * replacing this regex with something valid will make many titles valid.
 487          *
 488          * @return String regex string
 489          */
 490         static function getTitleInvalidRegex() {
 491                 static $rxTc = false;
 492                 if ( !$rxTc ) {
 493                         # Matching titles will be held as illegal.
 494                         $rxTc = '/' .
 495                                 # Any character not allowed is forbidden...
 496                                 '[^' . self::legalChars() . ']' .
 497                                 # URL percent encoding sequences interfere with the ability
 498                                 # to round-trip titles -- you can't link to them consistently.
 499                                 '|%[0-9A-Fa-f]{2}' .
 500                                 # XML/HTML character references produce similar issues.
 501                                 '|&[A-Za-z0-9\x80-\xff]+;' .
 502                                 '|&#[0-9]+;' .
 503                                 '|&#x[0-9A-Fa-f]+;' .
 504                                 '/S';
 505                 }
 506
 507                 return $rxTc;
 508         }
 509
 510         /**
 511          * Get a string representation of a title suitable for
 512          * including in a search index
 513          *
 514          * @param $ns Int a namespace index
 515          * @param $title String text-form main part
 516          * @return String a stripped-down title string ready for the search index
 517          */
 518         public static function indexTitle( $ns, $title ) {
 519                 global $wgContLang;
 520
 521                 $lc = SearchEngine::legalSearchChars() . '&#;';
 522                 $t = $wgContLang->normalizeForSearch( $title );
 523                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 524                 $t = $wgContLang->lc( $t );
 525
 526                 # Handle 's, s'
 527                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 528                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 529
 530                 $t = preg_replace( "/\\s+/", ' ', $t );
 531
 532                 if ( $ns == NS_FILE ) {
 533                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 534                 }
 535                 return trim( $t );
 536         }
 537
 538         /**
 539          * Make a prefixed DB key from a DB key and a namespace index
 540          *
 541          * @param $ns Int numerical representation of the namespace
 542          * @param $title String the DB key form the title
 543          * @param $fragment String The link fragment (after the "#")
 544          * @param $interwiki String The interwiki prefix
 545          * @return String the prefixed form of the title
 546          */
 547         public static function makeName( $ns, $title, $fragment = '', $interwiki = '' ) {
 548                 global $wgContLang;
 549
 550                 $namespace = $wgContLang->getNsText( $ns );
 551                 $name = $namespace == '' ? $title : "$namespace:$title";
 552                 if ( strval( $interwiki ) != '' ) {
 553                         $name = "$interwiki:$name";
 554                 }
 555                 if ( strval( $fragment ) != '' ) {
 556                         $name .= '#' . $fragment;
 557                 }
 558                 return $name;
 559         }
 560
 561         /**
 562          * Escape a text fragment, say from a link, for a URL
 563          *
 564          * @param $fragment string containing a URL or link fragment (after the "#")
 565          * @return String: escaped string
 566          */
 567         static function escapeFragmentForURL( $fragment ) {
 568                 # Note that we don't urlencode the fragment.  urlencoded Unicode
 569                 # fragments appear not to work in IE (at least up to 7) or in at least
 570                 # one version of Opera 9.x.  The W3C validator, for one, doesn't seem
 571                 # to care if they aren't encoded.
 572                 return Sanitizer::escapeId( $fragment, 'noninitial' );
 573         }
 574
 575         /**
 576          * Callback for usort() to do title sorts by (namespace, title)
 577          *
 578          * @param $a Title
 579          * @param $b Title
 580          *
 581          * @return Integer: result of string comparison, or namespace comparison
 582          */
 583         public static function compare( $a, $b ) {
 584                 if ( $a->getNamespace() == $b->getNamespace() ) {
 585                         return strcmp( $a->getText(), $b->getText() );
 586                 } else {
 587                         return $a->getNamespace() - $b->getNamespace();
 588                 }
 589         }
 590
 591         /**
 592          * Determine whether the object refers to a page within
 593          * this project.
 594          *
 595          * @return Bool TRUE if this is an in-project interwiki link or a wikilink, FALSE otherwise
 596          */
 597         public function isLocal() {
 598                 if ( $this->mInterwiki != '' ) {
 599                         return Interwiki::fetch( $this->mInterwiki )->isLocal();
 600                 } else {
 601                         return true;
 602                 }
 603         }
 604
 605         /**
 606          * Is this Title interwiki?
 607          *
 608          * @return Bool
 609          */
 610         public function isExternal() {
 611                 return ( $this->mInterwiki != '' );
 612         }
 613
 614         /**
 615          * Get the interwiki prefix (or null string)
 616          *
 617          * @return String Interwiki prefix
 618          */
 619         public function getInterwiki() {
 620                 return $this->mInterwiki;
 621         }
 622
 623         /**
 624          * Determine whether the object refers to a page within
 625          * this project and is transcludable.
 626          *
 627          * @return Bool TRUE if this is transcludable
 628          */
 629         public function isTrans() {
 630                 if ( $this->mInterwiki == '' ) {
 631                         return false;
 632                 }
 633
 634                 return Interwiki::fetch( $this->mInterwiki )->isTranscludable();
 635         }
 636
 637         /**
 638          * Returns the DB name of the distant wiki which owns the object.
 639          *
 640          * @return String the DB name
 641          */
 642         public function getTransWikiID() {
 643                 if ( $this->mInterwiki == '' ) {
 644                         return false;
 645                 }
 646
 647                 return Interwiki::fetch( $this->mInterwiki )->getWikiID();
 648         }
 649
 650         /**
 651          * Get the text form (spaces not underscores) of the main part
 652          *
 653          * @return String Main part of the title
 654          */
 655         public function getText() {
 656                 return $this->mTextform;
 657         }
 658
 659         /**
 660          * Get the URL-encoded form of the main part
 661          *
 662          * @return String Main part of the title, URL-encoded
 663          */
 664         public function getPartialURL() {
 665                 return $this->mUrlform;
 666         }
 667
 668         /**
 669          * Get the main part with underscores
 670          *
 671          * @return String: Main part of the title, with underscores
 672          */
 673         public function getDBkey() {
 674                 return $this->mDbkeyform;
 675         }
 676
 677         /**
 678          * Get the DB key with the initial letter case as specified by the user
 679          *
 680          * @return String DB key
 681          */
 682         function getUserCaseDBKey() {
 683                 return $this->mUserCaseDBKey;
 684         }
 685
 686         /**
 687          * Get the namespace index, i.e. one of the NS_xxxx constants.
 688          *
 689          * @return Integer: Namespace index
 690          */
 691         public function getNamespace() {
 692                 return $this->mNamespace;
 693         }
 694
 695         /**
 696          * Get the namespace text
 697          *
 698          * @return String: Namespace text
 699          */
 700         public function getNsText() {
 701                 global $wgContLang;
 702
 703                 if ( $this->mInterwiki != '' ) {
 704                         // This probably shouldn't even happen. ohh man, oh yuck.
 705                         // But for interwiki transclusion it sometimes does.
 706                         // Shit. Shit shit shit.
 707                         //
 708                         // Use the canonical namespaces if possible to try to
 709                         // resolve a foreign namespace.
 710                         if ( MWNamespace::exists( $this->mNamespace ) ) {
 711                                 return MWNamespace::getCanonicalName( $this->mNamespace );
 712                         }
 713                 }
 714
 715                 if ( $wgContLang->needsGenderDistinction() &&
 716                                 MWNamespace::hasGenderDistinction( $this->mNamespace ) ) {
 717                         $gender = GenderCache::singleton()->getGenderOf( $this->getText(), __METHOD__ );
 718                         return $wgContLang->getGenderNsText( $this->mNamespace, $gender );
 719                 }
 720
 721                 return $wgContLang->getNsText( $this->mNamespace );
 722         }
 723
 724         /**
 725          * Get the namespace text of the subject (rather than talk) page
 726          *
 727          * @return String Namespace text
 728          */
 729         public function getSubjectNsText() {
 730                 global $wgContLang;
 731                 return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
 732         }
 733
 734         /**
 735          * Get the namespace text of the talk page
 736          *
 737          * @return String Namespace text
 738          */
 739         public function getTalkNsText() {
 740                 global $wgContLang;
 741                 return( $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) ) );
 742         }
 743
 744         /**
 745          * Could this title have a corresponding talk page?
 746          *
 747          * @return Bool TRUE or FALSE
 748          */
 749         public function canTalk() {
 750                 return( MWNamespace::canTalk( $this->mNamespace ) );
 751         }
 752
 753         /**
 754          * Is this in a namespace that allows actual pages?
 755          *
 756          * @return Bool
 757          * @internal note -- uses hardcoded namespace index instead of constants
 758          */
 759         public function canExist() {
 760                 return $this->mNamespace >= NS_MAIN;
 761         }
 762
 763         /**
 764          * Can this title be added to a user's watchlist?
 765          *
 766          * @return Bool TRUE or FALSE
 767          */
 768         public function isWatchable() {
 769                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
 770         }
 771
 772         /**
 773          * Returns true if this is a special page.
 774          *
 775          * @return boolean
 776          */
 777         public function isSpecialPage() {
 778                 return $this->getNamespace() == NS_SPECIAL;
 779         }
 780
 781         /**
 782          * Returns true if this title resolves to the named special page
 783          *
 784          * @param $name String The special page name
 785          * @return boolean
 786          */
 787         public function isSpecial( $name ) {
 788                 if ( $this->isSpecialPage() ) {
 789                         list( $thisName, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $this->getDBkey() );
 790                         if ( $name == $thisName ) {
 791                                 return true;
 792                         }
 793                 }
 794                 return false;
 795         }
 796
 797         /**
 798          * If the Title refers to a special page alias which is not the local default, resolve
 799          * the alias, and localise the name as necessary.  Otherwise, return $this
 800          *
 801          * @return Title
 802          */
 803         public function fixSpecialName() {
 804                 if ( $this->isSpecialPage() ) {
 805                         list( $canonicalName, $par ) = SpecialPageFactory::resolveAlias( $this->mDbkeyform );
 806                         if ( $canonicalName ) {
 807                                 $localName = SpecialPageFactory::getLocalNameFor( $canonicalName, $par );
 808                                 if ( $localName != $this->mDbkeyform ) {
 809                                         return Title::makeTitle( NS_SPECIAL, $localName );
 810                                 }
 811                         }
 812                 }
 813                 return $this;
 814         }
 815
 816         /**
 817          * Returns true if the title is inside the specified namespace.
 818          *
 819          * Please make use of this instead of comparing to getNamespace()
 820          * This function is much more resistant to changes we may make
 821          * to namespaces than code that makes direct comparisons.
 822          * @param $ns int The namespace
 823          * @return bool
 824          * @since 1.19
 825          */
 826         public function inNamespace( $ns ) {
 827                 return MWNamespace::equals( $this->getNamespace(), $ns );
 828         }
 829
 830         /**
 831          * Returns true if the title is inside one of the specified namespaces.
 832          *
 833          * @param ...$namespaces The namespaces to check for
 834          * @return bool
 835          * @since 1.19
 836          */
 837         public function inNamespaces( /* ... */ ) {
 838                 $namespaces = func_get_args();
 839                 if ( count( $namespaces ) > 0 && is_array( $namespaces[0] ) ) {
 840                         $namespaces = $namespaces[0];
 841                 }
 842
 843                 foreach ( $namespaces as $ns ) {
 844                         if ( $this->inNamespace( $ns ) ) {
 845                                 return true;
 846                         }
 847                 }
 848
 849                 return false;
 850         }
 851
 852         /**
 853          * Returns true if the title has the same subject namespace as the
 854          * namespace specified.
 855          * For example this method will take NS_USER and return true if namespace
 856          * is either NS_USER or NS_USER_TALK since both of them have NS_USER
 857          * as their subject namespace.
 858          *
 859          * This is MUCH simpler than individually testing for equivilance
 860          * against both NS_USER and NS_USER_TALK, and is also forward compatible.
 861          * @since 1.19
 862          * @param $ns int
 863          * @return bool
 864          */
 865         public function hasSubjectNamespace( $ns ) {
 866                 return MWNamespace::subjectEquals( $this->getNamespace(), $ns );
 867         }
 868
 869         /**
 870          * Is this Title in a namespace which contains content?
 871          * In other words, is this a content page, for the purposes of calculating
 872          * statistics, etc?
 873          *
 874          * @return Boolean
 875          */
 876         public function isContentPage() {
 877                 return MWNamespace::isContent( $this->getNamespace() );
 878         }
 879
 880         /**
 881          * Would anybody with sufficient privileges be able to move this page?
 882          * Some pages just aren't movable.
 883          *
 884          * @return Bool TRUE or FALSE
 885          */
 886         public function isMovable() {
 887                 if ( !MWNamespace::isMovable( $this->getNamespace() ) || $this->getInterwiki() != '' ) {
 888                         // Interwiki title or immovable namespace. Hooks don't get to override here
 889                         return false;
 890                 }
 891
 892                 $result = true;
 893                 wfRunHooks( 'TitleIsMovable', array( $this, &$result ) );
 894                 return $result;
 895         }
 896
 897         /**
 898          * Is this the mainpage?
 899          * @note Title::newFromText seams to be sufficiently optimized by the title
 900          * cache that we don't need to over-optimize by doing direct comparisons and
 901          * acidentally creating new bugs where $title->equals( Title::newFromText() )
 902          * ends up reporting something differently than $title->isMainPage();
 903          *
 904          * @since 1.18
 905          * @return Bool
 906          */
 907         public function isMainPage() {
 908                 return $this->equals( Title::newMainPage() );
 909         }
 910
 911         /**
 912          * Is this a subpage?
 913          *
 914          * @return Bool
 915          */
 916         public function isSubpage() {
 917                 return MWNamespace::hasSubpages( $this->mNamespace )
 918                         ? strpos( $this->getText(), '/' ) !== false
 919                         : false;
 920         }
 921
 922         /**
 923          * Is this a conversion table for the LanguageConverter?
 924          *
 925          * @return Bool
 926          */
 927         public function isConversionTable() {
 928                 return $this->getNamespace() == NS_MEDIAWIKI &&
 929                         strpos( $this->getText(), 'Conversiontable' ) !== false;
 930         }
 931
 932         /**
 933          * Does that page contain wikitext, or it is JS, CSS or whatever?
 934          *
 935          * @return Bool
 936          */
 937         public function isWikitextPage() {
 938                 $retval = !$this->isCssOrJsPage() && !$this->isCssJsSubpage();
 939                 wfRunHooks( 'TitleIsWikitextPage', array( $this, &$retval ) );
 940                 return $retval;
 941         }
 942
 943         /**
 944          * Could this page contain custom CSS or JavaScript, based
 945          * on the title?
 946          *
 947          * @return Bool
 948          */
 949         public function isCssOrJsPage() {
 950                 $retval = $this->mNamespace == NS_MEDIAWIKI
 951                         && preg_match( '!\.(?:css|js)$!u', $this->mTextform ) > 0;
 952                 wfRunHooks( 'TitleIsCssOrJsPage', array( $this, &$retval ) );
 953                 return $retval;
 954         }
 955
 956         /**
 957          * Is this a .css or .js subpage of a user page?
 958          * @return Bool
 959          */
 960         public function isCssJsSubpage() {
 961                 return ( NS_USER == $this->mNamespace and preg_match( "/\\/.*\\.(?:css|js)$/", $this->mTextform ) );
 962         }
 963
 964         /**
 965          * Trim down a .css or .js subpage title to get the corresponding skin name
 966          *
 967          * @return string containing skin name from .css or .js subpage title
 968          */
 969         public function getSkinFromCssJsSubpage() {
 970                 $subpage = explode( '/', $this->mTextform );
 971                 $subpage = $subpage[ count( $subpage ) - 1 ];
 972                 $lastdot = strrpos( $subpage, '.' );
 973                 if ( $lastdot === false )
 974                         return $subpage; # Never happens: only called for names ending in '.css' or '.js'
 975                 return substr( $subpage, 0, $lastdot );
 976         }
 977
 978         /**
 979          * Is this a .css subpage of a user page?
 980          *
 981          * @return Bool
 982          */
 983         public function isCssSubpage() {
 984                 return ( NS_USER == $this->mNamespace && preg_match( "/\\/.*\\.css$/", $this->mTextform ) );
 985         }
 986
 987         /**
 988          * Is this a .js subpage of a user page?
 989          *
 990          * @return Bool
 991          */
 992         public function isJsSubpage() {
 993                 return ( NS_USER == $this->mNamespace && preg_match( "/\\/.*\\.js$/", $this->mTextform ) );
 994         }
 995
 996         /**
 997          * Is this a talk page of some sort?
 998          *
 999          * @return Bool
1000          */
1001         public function isTalkPage() {
1002                 return MWNamespace::isTalk( $this->getNamespace() );
1003         }
1004
1005         /**
1006          * Get a Title object associated with the talk page of this article
1007          *
1008          * @return Title the object for the talk page
1009          */
1010         public function getTalkPage() {
1011                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1012         }
1013
1014         /**
1015          * Get a title object associated with the subject page of this
1016          * talk page
1017          *
1018          * @return Title the object for the subject page
1019          */
1020         public function getSubjectPage() {
1021                 // Is this the same title?
1022                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
1023                 if ( $this->getNamespace() == $subjectNS ) {
1024                         return $this;
1025                 }
1026                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
1027         }
1028
1029         /**
1030          * Get the default namespace index, for when there is no namespace
1031          *
1032          * @return Int Default namespace index
1033          */
1034         public function getDefaultNamespace() {
1035                 return $this->mDefaultNamespace;
1036         }
1037
1038         /**
1039          * Get title for search index
1040          *
1041          * @return String a stripped-down title string ready for the
1042          *  search index
1043          */
1044         public function getIndexTitle() {
1045                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
1046         }
1047
1048         /**
1049          * Get the Title fragment (i.e.\ the bit after the #) in text form
1050          *
1051          * @return String Title fragment
1052          */
1053         public function getFragment() {
1054                 return $this->mFragment;
1055         }
1056
1057         /**
1058          * Get the fragment in URL form, including the "#" character if there is one
1059          * @return String Fragment in URL form
1060          */
1061         public function getFragmentForURL() {
1062                 if ( $this->mFragment == '' ) {
1063                         return '';
1064                 } else {
1065                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
1066                 }
1067         }
1068
1069         /**
1070          * Set the fragment for this title. Removes the first character from the
1071          * specified fragment before setting, so it assumes you're passing it with
1072          * an initial "#".
1073          *
1074          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
1075          * Still in active use privately.
1076          *
1077          * @param $fragment String text
1078          */
1079         public function setFragment( $fragment ) {
1080                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
1081         }
1082
1083         /**
1084          * Prefix some arbitrary text with the namespace or interwiki prefix
1085          * of this object
1086          *
1087          * @param $name String the text
1088          * @return String the prefixed text
1089          * @private
1090          */
1091         private function prefix( $name ) {
1092                 $p = '';
1093                 if ( $this->mInterwiki != '' ) {
1094                         $p = $this->mInterwiki . ':';
1095                 }
1096
1097                 if ( 0 != $this->mNamespace ) {
1098                         $p .= $this->getNsText() . ':';
1099                 }
1100                 return $p . $name;
1101         }
1102
1103         /**
1104          * Get the prefixed database key form
1105          *
1106          * @return String the prefixed title, with underscores and
1107          *  any interwiki and namespace prefixes
1108          */
1109         public function getPrefixedDBkey() {
1110                 $s = $this->prefix( $this->mDbkeyform );
1111                 $s = str_replace( ' ', '_', $s );
1112                 return $s;
1113         }
1114
1115         /**
1116          * Get the prefixed title with spaces.
1117          * This is the form usually used for display
1118          *
1119          * @return String the prefixed title, with spaces
1120          */
1121         public function getPrefixedText() {
1122                 // @todo FIXME: Bad usage of empty() ?
1123                 if ( empty( $this->mPrefixedText ) ) {
1124                         $s = $this->prefix( $this->mTextform );
1125                         $s = str_replace( '_', ' ', $s );
1126                         $this->mPrefixedText = $s;
1127                 }
1128                 return $this->mPrefixedText;
1129         }
1130
1131         /**
1132          * Return a string representation of this title
1133          *
1134          * @return String representation of this title
1135          */
1136         public function __toString() {
1137                 return $this->getPrefixedText();
1138         }
1139
1140         /**
1141          * Get the prefixed title with spaces, plus any fragment
1142          * (part beginning with '#')
1143          *
1144          * @return String the prefixed title, with spaces and the fragment, including '#'
1145          */
1146         public function getFullText() {
1147                 $text = $this->getPrefixedText();
1148                 if ( $this->mFragment != '' ) {
1149                         $text .= '#' . $this->mFragment;
1150                 }
1151                 return $text;
1152         }
1153
1154         /**
1155          * Get the base page name, i.e. the leftmost part before any slashes
1156          *
1157          * @return String Base name
1158          */
1159         public function getBaseText() {
1160                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1161                         return $this->getText();
1162                 }
1163
1164                 $parts = explode( '/', $this->getText() );
1165                 # Don't discard the real title if there's no subpage involved
1166                 if ( count( $parts ) > 1 ) {
1167                         unset( $parts[count( $parts ) - 1] );
1168                 }
1169                 return implode( '/', $parts );
1170         }
1171
1172         /**
1173          * Get the lowest-level subpage name, i.e. the rightmost part after any slashes
1174          *
1175          * @return String Subpage name
1176          */
1177         public function getSubpageText() {
1178                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1179                         return( $this->mTextform );
1180                 }
1181                 $parts = explode( '/', $this->mTextform );
1182                 return( $parts[count( $parts ) - 1] );
1183         }
1184
1185         /**
1186          * Get the HTML-escaped displayable text form.
1187          * Used for the title field in <a> tags.
1188          *
1189          * @return String the text, including any prefixes
1190          */
1191         public function getEscapedText() {
1192                 wfDeprecated( __METHOD__, '1.19' );
1193                 return htmlspecialchars( $this->getPrefixedText() );
1194         }
1195
1196         /**
1197          * Get a URL-encoded form of the subpage text
1198          *
1199          * @return String URL-encoded subpage name
1200          */
1201         public function getSubpageUrlForm() {
1202                 $text = $this->getSubpageText();
1203                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
1204                 return( $text );
1205         }
1206
1207         /**
1208          * Get a URL-encoded title (not an actual URL) including interwiki
1209          *
1210          * @return String the URL-encoded form
1211          */
1212         public function getPrefixedURL() {
1213                 $s = $this->prefix( $this->mDbkeyform );
1214                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
1215                 return $s;
1216         }
1217
1218         /**
1219          * Helper to fix up the get{Local,Full,Link,Canonical}URL args
1220          * get{Canonical,Full,Link,Local}URL methods accepted an optional
1221          * second argument named variant. This was deprecated in favor
1222          * of passing an array of option with a "variant" key
1223          * Once $query2 is removed for good, this helper can be dropped
1224          * andthe wfArrayToCGI moved to getLocalURL();
1225          *
1226          * @since 1.19 (r105919)
1227          * @param $query
1228          * @param $query2 bool
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          * @param $query string
1412          * @param $query2 bool|string
1413          * @return String the URL
1414          */
1415         public function escapeLocalURL( $query = '', $query2 = false ) {
1416                 wfDeprecated( __METHOD__, '1.19' );
1417                 return htmlspecialchars( $this->getLocalURL( $query, $query2 ) );
1418         }
1419
1420         /**
1421          * Get an HTML-escaped version of the URL form, suitable for
1422          * using in a link, including the server name and fragment
1423          *
1424          * See getLocalURL for the arguments.
1425          *
1426          * @see self::getLocalURL
1427          * @return String the URL
1428          */
1429         public function escapeFullURL( $query = '', $query2 = false ) {
1430                 wfDeprecated( __METHOD__, '1.19' );
1431                 return htmlspecialchars( $this->getFullURL( $query, $query2 ) );
1432         }
1433
1434         /**
1435          * Get the URL form for an internal link.
1436          * - Used in various Squid-related code, in case we have a different
1437          * internal hostname for the server from the exposed one.
1438          *
1439          * This uses $wgInternalServer to qualify the path, or $wgServer
1440          * if $wgInternalServer is not set. If the server variable used is
1441          * protocol-relative, the URL will be expanded to http://
1442          *
1443          * See getLocalURL for the arguments.
1444          *
1445          * @see self::getLocalURL
1446          * @return String the URL
1447          */
1448         public function getInternalURL( $query = '', $query2 = false ) {
1449                 global $wgInternalServer, $wgServer;
1450                 $query = self::fixUrlQueryArgs( $query, $query2 );
1451                 $server = $wgInternalServer !== false ? $wgInternalServer : $wgServer;
1452                 $url = wfExpandUrl( $server . $this->getLocalURL( $query ), PROTO_HTTP );
1453                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
1454                 return $url;
1455         }
1456
1457         /**
1458          * Get the URL for a canonical link, for use in things like IRC and
1459          * e-mail notifications. Uses $wgCanonicalServer and the
1460          * GetCanonicalURL hook.
1461          *
1462          * NOTE: Unlike getInternalURL(), the canonical URL includes the fragment
1463          *
1464          * See getLocalURL for the arguments.
1465          *
1466          * @see self::getLocalURL
1467          * @return string The URL
1468          * @since 1.18
1469          */
1470         public function getCanonicalURL( $query = '', $query2 = false ) {
1471                 $query = self::fixUrlQueryArgs( $query, $query2 );
1472                 $url = wfExpandUrl( $this->getLocalURL( $query ) . $this->getFragmentForURL(), PROTO_CANONICAL );
1473                 wfRunHooks( 'GetCanonicalURL', array( &$this, &$url, $query ) );
1474                 return $url;
1475         }
1476
1477         /**
1478          * HTML-escaped version of getCanonicalURL()
1479          *
1480          * See getLocalURL for the arguments.
1481          *
1482          * @see self::getLocalURL
1483          * @since 1.18
1484          * @return string
1485          */
1486         public function escapeCanonicalURL( $query = '', $query2 = false ) {
1487                 wfDeprecated( __METHOD__, '1.19' );
1488                 return htmlspecialchars( $this->getCanonicalURL( $query, $query2 ) );
1489         }
1490
1491         /**
1492          * Get the edit URL for this Title
1493          *
1494          * @return String the URL, or a null string if this is an
1495          *  interwiki link
1496          */
1497         public function getEditURL() {
1498                 if ( $this->mInterwiki != '' ) {
1499                         return '';
1500                 }
1501                 $s = $this->getLocalURL( 'action=edit' );
1502
1503                 return $s;
1504         }
1505
1506         /**
1507          * Is $wgUser watching this page?
1508          *
1509          * @return Bool
1510          */
1511         public function userIsWatching() {
1512                 global $wgUser;
1513
1514                 if ( is_null( $this->mWatched ) ) {
1515                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn() ) {
1516                                 $this->mWatched = false;
1517                         } else {
1518                                 $this->mWatched = $wgUser->isWatched( $this );
1519                         }
1520                 }
1521                 return $this->mWatched;
1522         }
1523
1524         /**
1525          * Can $wgUser read this page?
1526          *
1527          * @deprecated in 1.19; use userCan(), quickUserCan() or getUserPermissionsErrors() instead
1528          * @return Bool
1529          * @todo fold these checks into userCan()
1530          */
1531         public function userCanRead() {
1532                 wfDeprecated( __METHOD__, '1.19' );
1533                 return $this->userCan( 'read' );
1534         }
1535
1536         /**
1537          * Can $user perform $action on this page?
1538          * This skips potentially expensive cascading permission checks
1539          * as well as avoids expensive error formatting
1540          *
1541          * Suitable for use for nonessential UI controls in common cases, but
1542          * _not_ for functional access control.
1543          *
1544          * May provide false positives, but should never provide a false negative.
1545          *
1546          * @param $action String action that permission needs to be checked for
1547          * @param $user User to check (since 1.19); $wgUser will be used if not
1548          *              provided.
1549          * @return Bool
1550          */
1551         public function quickUserCan( $action, $user = null ) {
1552                 return $this->userCan( $action, $user, false );
1553         }
1554
1555         /**
1556          * Can $user perform $action on this page?
1557          *
1558          * @param $action String action that permission needs to be checked for
1559          * @param $user User to check (since 1.19); $wgUser will be used if not
1560          *   provided.
1561          * @param $doExpensiveQueries Bool Set this to false to avoid doing
1562          *   unnecessary queries.
1563          * @return Bool
1564          */
1565         public function userCan( $action, $user = null, $doExpensiveQueries = true ) {
1566                 if ( !$user instanceof User ) {
1567                         global $wgUser;
1568                         $user = $wgUser;
1569                 }
1570                 return !count( $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries, true ) );
1571         }
1572
1573         /**
1574          * Can $user perform $action on this page?
1575          *
1576          * @todo FIXME: This *does not* check throttles (User::pingLimiter()).
1577          *
1578          * @param $action String action that permission needs to be checked for
1579          * @param $user User to check
1580          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary
1581          *   queries by skipping checks for cascading protections and user blocks.
1582          * @param $ignoreErrors Array of Strings Set this to a list of message keys
1583          *   whose corresponding errors may be ignored.
1584          * @return Array of arguments to wfMsg to explain permissions problems.
1585          */
1586         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1587                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1588
1589                 // Remove the errors being ignored.
1590                 foreach ( $errors as $index => $error ) {
1591                         $error_key = is_array( $error ) ? $error[0] : $error;
1592
1593                         if ( in_array( $error_key, $ignoreErrors ) ) {
1594                                 unset( $errors[$index] );
1595                         }
1596                 }
1597
1598                 return $errors;
1599         }
1600
1601         /**
1602          * Permissions checks that fail most often, and which are easiest to test.
1603          *
1604          * @param $action String the action to check
1605          * @param $user User user to check
1606          * @param $errors Array list of current errors
1607          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1608          * @param $short Boolean short circuit on first error
1609          *
1610          * @return Array list of errors
1611          */
1612         private function checkQuickPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1613                 if ( $action == 'create' ) {
1614                         if ( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1615                                  ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1616                                 $errors[] = $user->isAnon() ? array( 'nocreatetext' ) : array( 'nocreate-loggedin' );
1617                         }
1618                 } elseif ( $action == 'move' ) {
1619                         if ( !$user->isAllowed( 'move-rootuserpages' )
1620                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1621                                 // Show user page-specific message only if the user can move other pages
1622                                 $errors[] = array( 'cant-move-user-page' );
1623                         }
1624
1625                         // Check if user is allowed to move files if it's a file
1626                         if ( $this->mNamespace == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1627                                 $errors[] = array( 'movenotallowedfile' );
1628                         }
1629
1630                         if ( !$user->isAllowed( 'move' ) ) {
1631                                 // User can't move anything
1632                                 global $wgGroupPermissions;
1633                                 $userCanMove = false;
1634                                 if ( isset( $wgGroupPermissions['user']['move'] ) ) {
1635                                         $userCanMove = $wgGroupPermissions['user']['move'];
1636                                 }
1637                                 $autoconfirmedCanMove = false;
1638                                 if ( isset( $wgGroupPermissions['autoconfirmed']['move'] ) ) {
1639                                         $autoconfirmedCanMove = $wgGroupPermissions['autoconfirmed']['move'];
1640                                 }
1641                                 if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
1642                                         // custom message if logged-in users without any special rights can move
1643                                         $errors[] = array( 'movenologintext' );
1644                                 } else {
1645                                         $errors[] = array( 'movenotallowed' );
1646                                 }
1647                         }
1648                 } elseif ( $action == 'move-target' ) {
1649                         if ( !$user->isAllowed( 'move' ) ) {
1650                                 // User can't move anything
1651                                 $errors[] = array( 'movenotallowed' );
1652                         } elseif ( !$user->isAllowed( 'move-rootuserpages' )
1653                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1654                                 // Show user page-specific message only if the user can move other pages
1655                                 $errors[] = array( 'cant-move-to-user-page' );
1656                         }
1657                 } elseif ( !$user->isAllowed( $action ) ) {
1658                         $errors[] = $this->missingPermissionError( $action, $short );
1659                 }
1660
1661                 return $errors;
1662         }
1663
1664         /**
1665          * Add the resulting error code to the errors array
1666          *
1667          * @param $errors Array list of current errors
1668          * @param $result Mixed result of errors
1669          *
1670          * @return Array list of errors
1671          */
1672         private function resultToError( $errors, $result ) {
1673                 if ( is_array( $result ) && count( $result ) && !is_array( $result[0] ) ) {
1674                         // A single array representing an error
1675                         $errors[] = $result;
1676                 } elseif ( is_array( $result ) && is_array( $result[0] ) ) {
1677                         // A nested array representing multiple errors
1678                         $errors = array_merge( $errors, $result );
1679                 } elseif ( $result !== '' && is_string( $result ) ) {
1680                         // A string representing a message-id
1681                         $errors[] = array( $result );
1682                 } elseif ( $result === false ) {
1683                         // a generic "We don't want them to do that"
1684                         $errors[] = array( 'badaccess-group0' );
1685                 }
1686                 return $errors;
1687         }
1688
1689         /**
1690          * Check various permission hooks
1691          *
1692          * @param $action String the action to check
1693          * @param $user User user to check
1694          * @param $errors Array list of current errors
1695          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1696          * @param $short Boolean short circuit on first error
1697          *
1698          * @return Array list of errors
1699          */
1700         private function checkPermissionHooks( $action, $user, $errors, $doExpensiveQueries, $short ) {
1701                 // Use getUserPermissionsErrors instead
1702                 $result = '';
1703                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1704                         return $result ? array() : array( array( 'badaccess-group0' ) );
1705                 }
1706                 // Check getUserPermissionsErrors hook
1707                 if ( !wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1708                         $errors = $this->resultToError( $errors, $result );
1709                 }
1710                 // Check getUserPermissionsErrorsExpensive hook
1711                 if ( $doExpensiveQueries && !( $short && count( $errors ) > 0 ) &&
1712                          !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) ) ) {
1713                         $errors = $this->resultToError( $errors, $result );
1714                 }
1715
1716                 return $errors;
1717         }
1718
1719         /**
1720          * Check permissions on special pages & namespaces
1721          *
1722          * @param $action String the action to check
1723          * @param $user User user to check
1724          * @param $errors Array list of current errors
1725          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1726          * @param $short Boolean short circuit on first error
1727          *
1728          * @return Array list of errors
1729          */
1730         private function checkSpecialsAndNSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1731                 # Only 'createaccount' and 'execute' can be performed on
1732                 # special pages, which don't actually exist in the DB.
1733                 $specialOKActions = array( 'createaccount', 'execute', 'read' );
1734                 if ( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions ) ) {
1735                         $errors[] = array( 'ns-specialprotected' );
1736                 }
1737
1738                 # Check $wgNamespaceProtection for restricted namespaces
1739                 if ( $this->isNamespaceProtected( $user ) ) {
1740                         $ns = $this->mNamespace == NS_MAIN ?
1741                                 wfMsg( 'nstab-main' ) : $this->getNsText();
1742                         $errors[] = $this->mNamespace == NS_MEDIAWIKI ?
1743                                 array( 'protectedinterface' ) : array( 'namespaceprotected',  $ns );
1744                 }
1745
1746                 return $errors;
1747         }
1748
1749         /**
1750          * Check CSS/JS sub-page permissions
1751          *
1752          * @param $action String the action to check
1753          * @param $user User user to check
1754          * @param $errors Array list of current errors
1755          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1756          * @param $short Boolean short circuit on first error
1757          *
1758          * @return Array list of errors
1759          */
1760         private function checkCSSandJSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1761                 # Protect css/js subpages of user pages
1762                 # XXX: this might be better using restrictions
1763                 # XXX: right 'editusercssjs' is deprecated, for backward compatibility only
1764                 if ( $action != 'patrol' && !$user->isAllowed( 'editusercssjs' )
1765                                 && !preg_match( '/^' . preg_quote( $user->getName(), '/' ) . '\//', $this->mTextform ) ) {
1766                         if ( $this->isCssSubpage() && !$user->isAllowed( 'editusercss' ) ) {
1767                                 $errors[] = array( 'customcssprotected' );
1768                         } elseif ( $this->isJsSubpage() && !$user->isAllowed( 'edituserjs' ) ) {
1769                                 $errors[] = array( 'customjsprotected' );
1770                         }
1771                 }
1772
1773                 return $errors;
1774         }
1775
1776         /**
1777          * Check against page_restrictions table requirements on this
1778          * page. The user must possess all required rights for this
1779          * action.
1780          *
1781          * @param $action String the action to check
1782          * @param $user User user to check
1783          * @param $errors Array list of current errors
1784          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1785          * @param $short Boolean short circuit on first error
1786          *
1787          * @return Array list of errors
1788          */
1789         private function checkPageRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1790                 foreach ( $this->getRestrictions( $action ) as $right ) {
1791                         // Backwards compatibility, rewrite sysop -> protect
1792                         if ( $right == 'sysop' ) {
1793                                 $right = 'protect';
1794                         }
1795                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1796                                 // Users with 'editprotected' permission can edit protected pages
1797                                 // without cascading option turned on.
1798                                 if ( $action != 'edit' || !$user->isAllowed( 'editprotected' )
1799                                         || $this->mCascadeRestriction )
1800                                 {
1801                                         $errors[] = array( 'protectedpagetext', $right );
1802                                 }
1803                         }
1804                 }
1805
1806                 return $errors;
1807         }
1808
1809         /**
1810          * Check restrictions on cascading pages.
1811          *
1812          * @param $action String the action to check
1813          * @param $user User to check
1814          * @param $errors Array list of current errors
1815          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1816          * @param $short Boolean short circuit on first error
1817          *
1818          * @return Array list of errors
1819          */
1820         private function checkCascadingSourcesRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1821                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1822                         # We /could/ use the protection level on the source page, but it's
1823                         # fairly ugly as we have to establish a precedence hierarchy for pages
1824                         # included by multiple cascade-protected pages. So just restrict
1825                         # it to people with 'protect' permission, as they could remove the
1826                         # protection anyway.
1827                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1828                         # Cascading protection depends on more than this page...
1829                         # Several cascading protected pages may include this page...
1830                         # Check each cascading level
1831                         # This is only for protection restrictions, not for all actions
1832                         if ( isset( $restrictions[$action] ) ) {
1833                                 foreach ( $restrictions[$action] as $right ) {
1834                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1835                                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1836                                                 $pages = '';
1837                                                 foreach ( $cascadingSources as $page )
1838                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1839                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1840                                         }
1841                                 }
1842                         }
1843                 }
1844
1845                 return $errors;
1846         }
1847
1848         /**
1849          * Check action permissions not already checked in checkQuickPermissions
1850          *
1851          * @param $action String the action to check
1852          * @param $user User to check
1853          * @param $errors Array list of current errors
1854          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1855          * @param $short Boolean short circuit on first error
1856          *
1857          * @return Array list of errors
1858          */
1859         private function checkActionPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1860                 global $wgDeleteRevisionsLimit, $wgLang;
1861
1862                 if ( $action == 'protect' ) {
1863                         if ( count( $this->getUserPermissionsErrorsInternal( 'edit', $user, $doExpensiveQueries, true ) ) ) {
1864                                 // If they can't edit, they shouldn't protect.
1865                                 $errors[] = array( 'protect-cantedit' );
1866                         }
1867                 } elseif ( $action == 'create' ) {
1868                         $title_protection = $this->getTitleProtection();
1869                         if( $title_protection ) {
1870                                 if( $title_protection['pt_create_perm'] == 'sysop' ) {
1871                                         $title_protection['pt_create_perm'] = 'protect'; // B/C
1872                                 }
1873                                 if( $title_protection['pt_create_perm'] == '' ||
1874                                         !$user->isAllowed( $title_protection['pt_create_perm'] ) )
1875                                 {
1876                                         $errors[] = array( 'titleprotected', User::whoIs( $title_protection['pt_user'] ), $title_protection['pt_reason'] );
1877                                 }
1878                         }
1879                 } elseif ( $action == 'move' ) {
1880                         // Check for immobile pages
1881                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1882                                 // Specific message for this case
1883                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1884                         } elseif ( !$this->isMovable() ) {
1885                                 // Less specific message for rarer cases
1886                                 $errors[] = array( 'immobile-source-page' );
1887                         }
1888                 } elseif ( $action == 'move-target' ) {
1889                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1890                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1891                         } elseif ( !$this->isMovable() ) {
1892                                 $errors[] = array( 'immobile-target-page' );
1893                         }
1894                 } elseif ( $action == 'delete' ) {
1895                         if ( $doExpensiveQueries && $wgDeleteRevisionsLimit
1896                                 && !$this->userCan( 'bigdelete', $user ) && $this->isBigDeletion() )
1897                         {
1898                                 $errors[] = array( 'delete-toobig', $wgLang->formatNum( $wgDeleteRevisionsLimit ) );
1899                         }
1900                 }
1901                 return $errors;
1902         }
1903
1904         /**
1905          * Check that the user isn't blocked from editting.
1906          *
1907          * @param $action String the action to check
1908          * @param $user User to check
1909          * @param $errors Array list of current errors
1910          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1911          * @param $short Boolean short circuit on first error
1912          *
1913          * @return Array list of errors
1914          */
1915         private function checkUserBlock( $action, $user, $errors, $doExpensiveQueries, $short ) {
1916                 // Account creation blocks handled at userlogin.
1917                 // Unblocking handled in SpecialUnblock
1918                 if( !$doExpensiveQueries || in_array( $action, array( 'createaccount', 'unblock' ) ) ) {
1919                         return $errors;
1920                 }
1921
1922                 global $wgContLang, $wgLang, $wgEmailConfirmToEdit;
1923
1924                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() ) {
1925                         $errors[] = array( 'confirmedittext' );
1926                 }
1927
1928                 if ( ( $action == 'edit' || $action == 'create' ) && !$user->isBlockedFrom( $this ) ) {
1929                         // Don't block the user from editing their own talk page unless they've been
1930                         // explicitly blocked from that too.
1931                 } elseif( $user->isBlocked() && $user->mBlock->prevents( $action ) !== false ) {
1932                         $block = $user->getBlock();
1933
1934                         // This is from OutputPage::blockedPage
1935                         // Copied at r23888 by werdna
1936
1937                         $id = $user->blockedBy();
1938                         $reason = $user->blockedFor();
1939                         if ( $reason == '' ) {
1940                                 $reason = wfMsg( 'blockednoreason' );
1941                         }
1942                         $ip = $user->getRequest()->getIP();
1943
1944                         if ( is_numeric( $id ) ) {
1945                                 $name = User::whoIs( $id );
1946                         } else {
1947                                 $name = $id;
1948                         }
1949
1950                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1951                         $blockid = $block->getId();
1952                         $blockExpiry = $block->getExpiry();
1953                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $block->mTimestamp ), true );
1954                         if ( $blockExpiry == 'infinity' ) {
1955                                 $blockExpiry = wfMessage( 'infiniteblock' )->text();
1956                         } else {
1957                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1958                         }
1959
1960                         $intended = strval( $block->getTarget() );
1961
1962                         $errors[] = array( ( $block->mAuto ? 'autoblockedtext' : 'blockedtext' ), $link, $reason, $ip, $name,
1963                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
1964                 }
1965
1966                 return $errors;
1967         }
1968
1969         /**
1970          * Check that the user is allowed to read this page.
1971          *
1972          * @param $action String the action to check
1973          * @param $user User to check
1974          * @param $errors Array list of current errors
1975          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1976          * @param $short Boolean short circuit on first error
1977          *
1978          * @return Array list of errors
1979          */
1980         private function checkReadPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1981                 global $wgWhitelistRead, $wgGroupPermissions, $wgRevokePermissions;
1982                 static $useShortcut = null;
1983
1984                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
1985                 if ( is_null( $useShortcut ) ) {
1986                         $useShortcut = true;
1987                         if ( empty( $wgGroupPermissions['*']['read'] ) ) {
1988                                 # Not a public wiki, so no shortcut
1989                                 $useShortcut = false;
1990                         } elseif ( !empty( $wgRevokePermissions ) ) {
1991                                 /**
1992                                  * Iterate through each group with permissions being revoked (key not included since we don't care
1993                                  * what the group name is), then check if the read permission is being revoked. If it is, then
1994                                  * we don't use the shortcut below since the user might not be able to read, even though anon
1995                                  * reading is allowed.
1996                                  */
1997                                 foreach ( $wgRevokePermissions as $perms ) {
1998                                         if ( !empty( $perms['read'] ) ) {
1999                                                 # We might be removing the read right from the user, so no shortcut
2000                                                 $useShortcut = false;
2001                                                 break;
2002                                         }
2003                                 }
2004                         }
2005                 }
2006
2007                 $whitelisted = false;
2008                 if ( $useShortcut ) {
2009                         # Shortcut for public wikis, allows skipping quite a bit of code
2010                         $whitelisted = true;
2011                 } elseif ( $user->isAllowed( 'read' ) ) {
2012                         # If the user is allowed to read pages, he is allowed to read all pages
2013                         $whitelisted = true;
2014                 } elseif ( $this->isSpecial( 'Userlogin' )
2015                         || $this->isSpecial( 'ChangePassword' )
2016                         || $this->isSpecial( 'PasswordReset' )
2017                 ) {
2018                         # Always grant access to the login page.
2019                         # Even anons need to be able to log in.
2020                         $whitelisted = true;
2021                 } elseif ( is_array( $wgWhitelistRead ) && count( $wgWhitelistRead ) ) {
2022                         # Time to check the whitelist
2023                         # Only do these checks is there's something to check against
2024                         $name = $this->getPrefixedText();
2025                         $dbName = $this->getPrefixedDBKey();
2026
2027                         // Check for explicit whitelisting with and without underscores
2028                         if ( in_array( $name, $wgWhitelistRead, true ) || in_array( $dbName, $wgWhitelistRead, true ) ) {
2029                                 $whitelisted = true;
2030                         } elseif ( $this->getNamespace() == NS_MAIN ) {
2031                                 # Old settings might have the title prefixed with
2032                                 # a colon for main-namespace pages
2033                                 if ( in_array( ':' . $name, $wgWhitelistRead ) ) {
2034                                         $whitelisted = true;
2035                                 }
2036                         } elseif ( $this->isSpecialPage() ) {
2037                                 # If it's a special page, ditch the subpage bit and check again
2038                                 $name = $this->getDBkey();
2039                                 list( $name, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $name );
2040                                 if ( $name !== false ) {
2041                                         $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
2042                                         if ( in_array( $pure, $wgWhitelistRead, true ) ) {
2043                                                 $whitelisted = true;
2044                                         }
2045                                 }
2046                         }
2047                 }
2048
2049                 if ( !$whitelisted ) {
2050                         # If the title is not whitelisted, give extensions a chance to do so...
2051                         wfRunHooks( 'TitleReadWhitelist', array( $this, $user, &$whitelisted ) );
2052                         if ( !$whitelisted ) {
2053                                 $errors[] = $this->missingPermissionError( $action, $short );
2054                         }
2055                 }
2056
2057                 return $errors;
2058         }
2059
2060         /**
2061          * Get a description array when the user doesn't have the right to perform
2062          * $action (i.e. when User::isAllowed() returns false)
2063          *
2064          * @param $action String the action to check
2065          * @param $short Boolean short circuit on first error
2066          * @return Array list of errors
2067          */
2068         private function missingPermissionError( $action, $short ) {
2069                 // We avoid expensive display logic for quickUserCan's and such
2070                 if ( $short ) {
2071                         return array( 'badaccess-group0' );
2072                 }
2073
2074                 $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
2075                         User::getGroupsWithPermission( $action ) );
2076
2077                 if ( count( $groups ) ) {
2078                         global $wgLang;
2079                         return array(
2080                                 'badaccess-groups',
2081                                 $wgLang->commaList( $groups ),
2082                                 count( $groups )
2083                         );
2084                 } else {
2085                         return array( 'badaccess-group0' );
2086                 }
2087         }
2088
2089         /**
2090          * Can $user perform $action on this page? This is an internal function,
2091          * which checks ONLY that previously checked by userCan (i.e. it leaves out
2092          * checks on wfReadOnly() and blocks)
2093          *
2094          * @param $action String action that permission needs to be checked for
2095          * @param $user User to check
2096          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary queries.
2097          * @param $short Bool Set this to true to stop after the first permission error.
2098          * @return Array of arrays of the arguments to wfMsg to explain permissions problems.
2099          */
2100         protected function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true, $short = false ) {
2101                 wfProfileIn( __METHOD__ );
2102
2103                 # Read has special handling
2104                 if ( $action == 'read' ) {
2105                         $checks = array(
2106                                 'checkPermissionHooks',
2107                                 'checkReadPermissions',
2108                         );
2109                 } else {
2110                         $checks = array(
2111                                 'checkQuickPermissions',
2112                                 'checkPermissionHooks',
2113                                 'checkSpecialsAndNSPermissions',
2114                                 'checkCSSandJSPermissions',
2115                                 'checkPageRestrictions',
2116                                 'checkCascadingSourcesRestrictions',
2117                                 'checkActionPermissions',
2118                                 'checkUserBlock'
2119                         );
2120                 }
2121
2122                 $errors = array();
2123                 while( count( $checks ) > 0 &&
2124                                 !( $short && count( $errors ) > 0 ) ) {
2125                         $method = array_shift( $checks );
2126                         $errors = $this->$method( $action, $user, $errors, $doExpensiveQueries, $short );
2127                 }
2128
2129                 wfProfileOut( __METHOD__ );
2130                 return $errors;
2131         }
2132
2133         /**
2134          * Protect css subpages of user pages: can $wgUser edit
2135          * this page?
2136          *
2137          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2138          * @return Bool
2139          */
2140         public function userCanEditCssSubpage() {
2141                 global $wgUser;
2142                 wfDeprecated( __METHOD__, '1.19' );
2143                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'editusercss' ) )
2144                         || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2145         }
2146
2147         /**
2148          * Protect js subpages of user pages: can $wgUser edit
2149          * this page?
2150          *
2151          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2152          * @return Bool
2153          */
2154         public function userCanEditJsSubpage() {
2155                 global $wgUser;
2156                 wfDeprecated( __METHOD__, '1.19' );
2157                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'edituserjs' ) )
2158                            || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2159         }
2160
2161         /**
2162          * Get a filtered list of all restriction types supported by this wiki.
2163          * @param bool $exists True to get all restriction types that apply to
2164          * titles that do exist, False for all restriction types that apply to
2165          * titles that do not exist
2166          * @return array
2167          */
2168         public static function getFilteredRestrictionTypes( $exists = true ) {
2169                 global $wgRestrictionTypes;
2170                 $types = $wgRestrictionTypes;
2171                 if ( $exists ) {
2172                         # Remove the create restriction for existing titles
2173                         $types = array_diff( $types, array( 'create' ) );
2174                 } else {
2175                         # Only the create and upload restrictions apply to non-existing titles
2176                         $types = array_intersect( $types, array( 'create', 'upload' ) );
2177                 }
2178                 return $types;
2179         }
2180
2181         /**
2182          * Returns restriction types for the current Title
2183          *
2184          * @return array applicable restriction types
2185          */
2186         public function getRestrictionTypes() {
2187                 if ( $this->isSpecialPage() ) {
2188                         return array();
2189                 }
2190
2191                 $types = self::getFilteredRestrictionTypes( $this->exists() );
2192
2193                 if ( $this->getNamespace() != NS_FILE ) {
2194                         # Remove the upload restriction for non-file titles
2195                         $types = array_diff( $types, array( 'upload' ) );
2196                 }
2197
2198                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
2199
2200                 wfDebug( __METHOD__ . ': applicable restrictions to [[' .
2201                         $this->getPrefixedText() . ']] are {' . implode( ',', $types ) . "}\n" );
2202
2203                 return $types;
2204         }
2205
2206         /**
2207          * Is this title subject to title protection?
2208          * Title protection is the one applied against creation of such title.
2209          *
2210          * @return Mixed An associative array representing any existent title
2211          *   protection, or false if there's none.
2212          */
2213         private function getTitleProtection() {
2214                 // Can't protect pages in special namespaces
2215                 if ( $this->getNamespace() < 0 ) {
2216                         return false;
2217                 }
2218
2219                 // Can't protect pages that exist.
2220                 if ( $this->exists() ) {
2221                         return false;
2222                 }
2223
2224                 if ( !isset( $this->mTitleProtection ) ) {
2225                         $dbr = wfGetDB( DB_SLAVE );
2226                         $res = $dbr->select( 'protected_titles', '*',
2227                                 array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2228                                 __METHOD__ );
2229
2230                         // fetchRow returns false if there are no rows.
2231                         $this->mTitleProtection = $dbr->fetchRow( $res );
2232                 }
2233                 return $this->mTitleProtection;
2234         }
2235
2236         /**
2237          * Update the title protection status
2238          *
2239          * @deprecated in 1.19; will be removed in 1.20. Use WikiPage::doUpdateRestrictions() instead.
2240          * @param $create_perm String Permission required for creation
2241          * @param $reason String Reason for protection
2242          * @param $expiry String Expiry timestamp
2243          * @return boolean true
2244          */
2245         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
2246                 wfDeprecated( __METHOD__, '1.19' );
2247
2248                 global $wgUser;
2249
2250                 $limit = array( 'create' => $create_perm );
2251                 $expiry = array( 'create' => $expiry );
2252
2253                 $page = WikiPage::factory( $this );
2254                 $status = $page->doUpdateRestrictions( $limit, $expiry, false, $reason, $wgUser );
2255
2256                 return $status->isOK();
2257         }
2258
2259         /**
2260          * Remove any title protection due to page existing
2261          */
2262         public function deleteTitleProtection() {
2263                 $dbw = wfGetDB( DB_MASTER );
2264
2265                 $dbw->delete(
2266                         'protected_titles',
2267                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2268                         __METHOD__
2269                 );
2270                 $this->mTitleProtection = false;
2271         }
2272
2273         /**
2274          * Is this page "semi-protected" - the *only* protection is autoconfirm?
2275          *
2276          * @param $action String Action to check (default: edit)
2277          * @return Bool
2278          */
2279         public function isSemiProtected( $action = 'edit' ) {
2280                 if ( $this->exists() ) {
2281                         $restrictions = $this->getRestrictions( $action );
2282                         if ( count( $restrictions ) > 0 ) {
2283                                 foreach ( $restrictions as $restriction ) {
2284                                         if ( strtolower( $restriction ) != 'autoconfirmed' ) {
2285                                                 return false;
2286                                         }
2287                                 }
2288                         } else {
2289                                 # Not protected
2290                                 return false;
2291                         }
2292                         return true;
2293                 } else {
2294                         # If it doesn't exist, it can't be protected
2295                         return false;
2296                 }
2297         }
2298
2299         /**
2300          * Does the title correspond to a protected article?
2301          *
2302          * @param $action String the action the page is protected from,
2303          * by default checks all actions.
2304          * @return Bool
2305          */
2306         public function isProtected( $action = '' ) {
2307                 global $wgRestrictionLevels;
2308
2309                 $restrictionTypes = $this->getRestrictionTypes();
2310
2311                 # Special pages have inherent protection
2312                 if( $this->isSpecialPage() ) {
2313                         return true;
2314                 }
2315
2316                 # Check regular protection levels
2317                 foreach ( $restrictionTypes as $type ) {
2318                         if ( $action == $type || $action == '' ) {
2319                                 $r = $this->getRestrictions( $type );
2320                                 foreach ( $wgRestrictionLevels as $level ) {
2321                                         if ( in_array( $level, $r ) && $level != '' ) {
2322                                                 return true;
2323                                         }
2324                                 }
2325                         }
2326                 }
2327
2328                 return false;
2329         }
2330
2331         /**
2332          * Determines if $user is unable to edit this page because it has been protected
2333          * by $wgNamespaceProtection.
2334          *
2335          * @param $user User object to check permissions
2336          * @return Bool
2337          */
2338         public function isNamespaceProtected( User $user ) {
2339                 global $wgNamespaceProtection;
2340
2341                 if ( isset( $wgNamespaceProtection[$this->mNamespace] ) ) {
2342                         foreach ( (array)$wgNamespaceProtection[$this->mNamespace] as $right ) {
2343                                 if ( $right != '' && !$user->isAllowed( $right ) ) {
2344                                         return true;
2345                                 }
2346                         }
2347                 }
2348                 return false;
2349         }
2350
2351         /**
2352          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
2353          *
2354          * @return Bool If the page is subject to cascading restrictions.
2355          */
2356         public function isCascadeProtected() {
2357                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
2358                 return ( $sources > 0 );
2359         }
2360
2361         /**
2362          * Cascading protection: Get the source of any cascading restrictions on this page.
2363          *
2364          * @param $getPages Bool Whether or not to retrieve the actual pages
2365          *        that the restrictions have come from.
2366          * @return Mixed Array of Title objects of the pages from which cascading restrictions
2367          *     have come, false for none, or true if such restrictions exist, but $getPages
2368          *     was not set.  The restriction array is an array of each type, each of which
2369          *     contains a array of unique groups.
2370          */
2371         public function getCascadeProtectionSources( $getPages = true ) {
2372                 global $wgContLang;
2373                 $pagerestrictions = array();
2374
2375                 if ( isset( $this->mCascadeSources ) && $getPages ) {
2376                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
2377                 } elseif ( isset( $this->mHasCascadingRestrictions ) && !$getPages ) {
2378                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
2379                 }
2380
2381                 wfProfileIn( __METHOD__ );
2382
2383                 $dbr = wfGetDB( DB_SLAVE );
2384
2385                 if ( $this->getNamespace() == NS_FILE ) {
2386                         $tables = array( 'imagelinks', 'page_restrictions' );
2387                         $where_clauses = array(
2388                                 'il_to' => $this->getDBkey(),
2389                                 'il_from=pr_page',
2390                                 'pr_cascade' => 1
2391                         );
2392                 } else {
2393                         $tables = array( 'templatelinks', 'page_restrictions' );
2394                         $where_clauses = array(
2395                                 'tl_namespace' => $this->getNamespace(),
2396                                 'tl_title' => $this->getDBkey(),
2397                                 'tl_from=pr_page',
2398                                 'pr_cascade' => 1
2399                         );
2400                 }
2401
2402                 if ( $getPages ) {
2403                         $cols = array( 'pr_page', 'page_namespace', 'page_title',
2404                                                    'pr_expiry', 'pr_type', 'pr_level' );
2405                         $where_clauses[] = 'page_id=pr_page';
2406                         $tables[] = 'page';
2407                 } else {
2408                         $cols = array( 'pr_expiry' );
2409                 }
2410
2411                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
2412
2413                 $sources = $getPages ? array() : false;
2414                 $now = wfTimestampNow();
2415                 $purgeExpired = false;
2416
2417                 foreach ( $res as $row ) {
2418                         $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2419                         if ( $expiry > $now ) {
2420                                 if ( $getPages ) {
2421                                         $page_id = $row->pr_page;
2422                                         $page_ns = $row->page_namespace;
2423                                         $page_title = $row->page_title;
2424                                         $sources[$page_id] = Title::makeTitle( $page_ns, $page_title );
2425                                         # Add groups needed for each restriction type if its not already there
2426                                         # Make sure this restriction type still exists
2427
2428                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
2429                                                 $pagerestrictions[$row->pr_type] = array();
2430                                         }
2431
2432                                         if ( isset( $pagerestrictions[$row->pr_type] ) &&
2433                                                  !in_array( $row->pr_level, $pagerestrictions[$row->pr_type] ) ) {
2434                                                 $pagerestrictions[$row->pr_type][] = $row->pr_level;
2435                                         }
2436                                 } else {
2437                                         $sources = true;
2438                                 }
2439                         } else {
2440                                 // Trigger lazy purge of expired restrictions from the db
2441                                 $purgeExpired = true;
2442                         }
2443                 }
2444                 if ( $purgeExpired ) {
2445                         Title::purgeExpiredRestrictions();
2446                 }
2447
2448                 if ( $getPages ) {
2449                         $this->mCascadeSources = $sources;
2450                         $this->mCascadingRestrictions = $pagerestrictions;
2451                 } else {
2452                         $this->mHasCascadingRestrictions = $sources;
2453                 }
2454
2455                 wfProfileOut( __METHOD__ );
2456                 return array( $sources, $pagerestrictions );
2457         }
2458
2459         /**
2460          * Accessor/initialisation for mRestrictions
2461          *
2462          * @param $action String action that permission needs to be checked for
2463          * @return Array of Strings the array of groups allowed to edit this article
2464          */
2465         public function getRestrictions( $action ) {
2466                 if ( !$this->mRestrictionsLoaded ) {
2467                         $this->loadRestrictions();
2468                 }
2469                 return isset( $this->mRestrictions[$action] )
2470                                 ? $this->mRestrictions[$action]
2471                                 : array();
2472         }
2473
2474         /**
2475          * Get the expiry time for the restriction against a given action
2476          *
2477          * @param $action
2478          * @return String|Bool 14-char timestamp, or 'infinity' if the page is protected forever
2479          *     or not protected at all, or false if the action is not recognised.
2480          */
2481         public function getRestrictionExpiry( $action ) {
2482                 if ( !$this->mRestrictionsLoaded ) {
2483                         $this->loadRestrictions();
2484                 }
2485                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2486         }
2487
2488         /**
2489          * Returns cascading restrictions for the current article
2490          *
2491          * @return Boolean
2492          */
2493         function areRestrictionsCascading() {
2494                 if ( !$this->mRestrictionsLoaded ) {
2495                         $this->loadRestrictions();
2496                 }
2497
2498                 return $this->mCascadeRestriction;
2499         }
2500
2501         /**
2502          * Loads a string into mRestrictions array
2503          *
2504          * @param $res Resource restrictions as an SQL result.
2505          * @param $oldFashionedRestrictions String comma-separated list of page
2506          *        restrictions from page table (pre 1.10)
2507          */
2508         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
2509                 $rows = array();
2510
2511                 foreach ( $res as $row ) {
2512                         $rows[] = $row;
2513                 }
2514
2515                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
2516         }
2517
2518         /**
2519          * Compiles list of active page restrictions from both page table (pre 1.10)
2520          * and page_restrictions table for this existing page.
2521          * Public for usage by LiquidThreads.
2522          *
2523          * @param $rows array of db result objects
2524          * @param $oldFashionedRestrictions string comma-separated list of page
2525          *        restrictions from page table (pre 1.10)
2526          */
2527         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
2528                 global $wgContLang;
2529                 $dbr = wfGetDB( DB_SLAVE );
2530
2531                 $restrictionTypes = $this->getRestrictionTypes();
2532
2533                 foreach ( $restrictionTypes as $type ) {
2534                         $this->mRestrictions[$type] = array();
2535                         $this->mRestrictionsExpiry[$type] = $wgContLang->formatExpiry( '', TS_MW );
2536                 }
2537
2538                 $this->mCascadeRestriction = false;
2539
2540                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2541
2542                 if ( $oldFashionedRestrictions === null ) {
2543                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2544                                 array( 'page_id' => $this->getArticleID() ), __METHOD__ );
2545                 }
2546
2547                 if ( $oldFashionedRestrictions != '' ) {
2548
2549                         foreach ( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2550                                 $temp = explode( '=', trim( $restrict ) );
2551                                 if ( count( $temp ) == 1 ) {
2552                                         // old old format should be treated as edit/move restriction
2553                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2554                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2555                                 } else {
2556                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
2557                                 }
2558                         }
2559
2560                         $this->mOldRestrictions = true;
2561
2562                 }
2563
2564                 if ( count( $rows ) ) {
2565                         # Current system - load second to make them override.
2566                         $now = wfTimestampNow();
2567                         $purgeExpired = false;
2568
2569                         # Cycle through all the restrictions.
2570                         foreach ( $rows as $row ) {
2571
2572                                 // Don't take care of restrictions types that aren't allowed
2573                                 if ( !in_array( $row->pr_type, $restrictionTypes ) )
2574                                         continue;
2575
2576                                 // This code should be refactored, now that it's being used more generally,
2577                                 // But I don't really see any harm in leaving it in Block for now -werdna
2578                                 $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2579
2580                                 // Only apply the restrictions if they haven't expired!
2581                                 if ( !$expiry || $expiry > $now ) {
2582                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2583                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2584
2585                                         $this->mCascadeRestriction |= $row->pr_cascade;
2586                                 } else {
2587                                         // Trigger a lazy purge of expired restrictions
2588                                         $purgeExpired = true;
2589                                 }
2590                         }
2591
2592                         if ( $purgeExpired ) {
2593                                 Title::purgeExpiredRestrictions();
2594                         }
2595                 }
2596
2597                 $this->mRestrictionsLoaded = true;
2598         }
2599
2600         /**
2601          * Load restrictions from the page_restrictions table
2602          *
2603          * @param $oldFashionedRestrictions String comma-separated list of page
2604          *        restrictions from page table (pre 1.10)
2605          */
2606         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2607                 global $wgContLang;
2608                 if ( !$this->mRestrictionsLoaded ) {
2609                         if ( $this->exists() ) {
2610                                 $dbr = wfGetDB( DB_SLAVE );
2611
2612                                 $res = $dbr->select(
2613                                         'page_restrictions',
2614                                         '*',
2615                                         array( 'pr_page' => $this->getArticleID() ),
2616                                         __METHOD__
2617                                 );
2618
2619                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2620                         } else {
2621                                 $title_protection = $this->getTitleProtection();
2622
2623                                 if ( $title_protection ) {
2624                                         $now = wfTimestampNow();
2625                                         $expiry = $wgContLang->formatExpiry( $title_protection['pt_expiry'], TS_MW );
2626
2627                                         if ( !$expiry || $expiry > $now ) {
2628                                                 // Apply the restrictions
2629                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2630                                                 $this->mRestrictions['create'] = explode( ',', trim( $title_protection['pt_create_perm'] ) );
2631                                         } else { // Get rid of the old restrictions
2632                                                 Title::purgeExpiredRestrictions();
2633                                                 $this->mTitleProtection = false;
2634                                         }
2635                                 } else {
2636                                         $this->mRestrictionsExpiry['create'] = $wgContLang->formatExpiry( '', TS_MW );
2637                                 }
2638                                 $this->mRestrictionsLoaded = true;
2639                         }
2640                 }
2641         }
2642
2643         /**
2644          * Flush the protection cache in this object and force reload from the database.
2645          * This is used when updating protection from WikiPage::doUpdateRestrictions().
2646          */
2647         public function flushRestrictions() {
2648                 $this->mRestrictionsLoaded = false;
2649                 $this->mTitleProtection = null;
2650         }
2651
2652         /**
2653          * Purge expired restrictions from the page_restrictions table
2654          */
2655         static function purgeExpiredRestrictions() {
2656                 $dbw = wfGetDB( DB_MASTER );
2657                 $dbw->delete(
2658                         'page_restrictions',
2659                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2660                         __METHOD__
2661                 );
2662
2663                 $dbw->delete(
2664                         'protected_titles',
2665                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2666                         __METHOD__
2667                 );
2668         }
2669
2670         /**
2671          * Does this have subpages?  (Warning, usually requires an extra DB query.)
2672          *
2673          * @return Bool
2674          */
2675         public function hasSubpages() {
2676                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
2677                         # Duh
2678                         return false;
2679                 }
2680
2681                 # We dynamically add a member variable for the purpose of this method
2682                 # alone to cache the result.  There's no point in having it hanging
2683                 # around uninitialized in every Title object; therefore we only add it
2684                 # if needed and don't declare it statically.
2685                 if ( isset( $this->mHasSubpages ) ) {
2686                         return $this->mHasSubpages;
2687                 }
2688
2689                 $subpages = $this->getSubpages( 1 );
2690                 if ( $subpages instanceof TitleArray ) {
2691                         return $this->mHasSubpages = (bool)$subpages->count();
2692                 }
2693                 return $this->mHasSubpages = false;
2694         }
2695
2696         /**
2697          * Get all subpages of this page.
2698          *
2699          * @param $limit Int maximum number of subpages to fetch; -1 for no limit
2700          * @return mixed TitleArray, or empty array if this page's namespace
2701          *  doesn't allow subpages
2702          */
2703         public function getSubpages( $limit = -1 ) {
2704                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
2705                         return array();
2706                 }
2707
2708                 $dbr = wfGetDB( DB_SLAVE );
2709                 $conds['page_namespace'] = $this->getNamespace();
2710                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
2711                 $options = array();
2712                 if ( $limit > -1 ) {
2713                         $options['LIMIT'] = $limit;
2714                 }
2715                 return $this->mSubpages = TitleArray::newFromResult(
2716                         $dbr->select( 'page',
2717                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
2718                                 $conds,
2719                                 __METHOD__,
2720                                 $options
2721                         )
2722                 );
2723         }
2724
2725         /**
2726          * Is there a version of this page in the deletion archive?
2727          *
2728          * @return Int the number of archived revisions
2729          */
2730         public function isDeleted() {
2731                 if ( $this->getNamespace() < 0 ) {
2732                         $n = 0;
2733                 } else {
2734                         $dbr = wfGetDB( DB_SLAVE );
2735
2736                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2737                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2738                                 __METHOD__
2739                         );
2740                         if ( $this->getNamespace() == NS_FILE ) {
2741                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2742                                         array( 'fa_name' => $this->getDBkey() ),
2743                                         __METHOD__
2744                                 );
2745                         }
2746                 }
2747                 return (int)$n;
2748         }
2749
2750         /**
2751          * Is there a version of this page in the deletion archive?
2752          *
2753          * @return Boolean
2754          */
2755         public function isDeletedQuick() {
2756                 if ( $this->getNamespace() < 0 ) {
2757                         return false;
2758                 }
2759                 $dbr = wfGetDB( DB_SLAVE );
2760                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2761                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2762                         __METHOD__
2763                 );
2764                 if ( !$deleted && $this->getNamespace() == NS_FILE ) {
2765                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2766                                 array( 'fa_name' => $this->getDBkey() ),
2767                                 __METHOD__
2768                         );
2769                 }
2770                 return $deleted;
2771         }
2772
2773         /**
2774          * Get the article ID for this Title from the link cache,
2775          * adding it if necessary
2776          *
2777          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select
2778          *  for update
2779          * @return Int the ID
2780          */
2781         public function getArticleID( $flags = 0 ) {
2782                 if ( $this->getNamespace() < 0 ) {
2783                         return $this->mArticleID = 0;
2784                 }
2785                 $linkCache = LinkCache::singleton();
2786                 if ( $flags & self::GAID_FOR_UPDATE ) {
2787                         $oldUpdate = $linkCache->forUpdate( true );
2788                         $linkCache->clearLink( $this );
2789                         $this->mArticleID = $linkCache->addLinkObj( $this );
2790                         $linkCache->forUpdate( $oldUpdate );
2791                 } else {
2792                         if ( -1 == $this->mArticleID ) {
2793                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2794                         }
2795                 }
2796                 return $this->mArticleID;
2797         }
2798
2799         /**
2800          * Is this an article that is a redirect page?
2801          * Uses link cache, adding it if necessary
2802          *
2803          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2804          * @return Bool
2805          */
2806         public function isRedirect( $flags = 0 ) {
2807                 if ( !is_null( $this->mRedirect ) ) {
2808                         return $this->mRedirect;
2809                 }
2810                 # Calling getArticleID() loads the field from cache as needed
2811                 if ( !$this->getArticleID( $flags ) ) {
2812                         return $this->mRedirect = false;
2813                 }
2814                 $linkCache = LinkCache::singleton();
2815                 $this->mRedirect = (bool)$linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2816
2817                 return $this->mRedirect;
2818         }
2819
2820         /**
2821          * What is the length of this page?
2822          * Uses link cache, adding it if necessary
2823          *
2824          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2825          * @return Int
2826          */
2827         public function getLength( $flags = 0 ) {
2828                 if ( $this->mLength != -1 ) {
2829                         return $this->mLength;
2830                 }
2831                 # Calling getArticleID() loads the field from cache as needed
2832                 if ( !$this->getArticleID( $flags ) ) {
2833                         return $this->mLength = 0;
2834                 }
2835                 $linkCache = LinkCache::singleton();
2836                 $this->mLength = intval( $linkCache->getGoodLinkFieldObj( $this, 'length' ) );
2837
2838                 return $this->mLength;
2839         }
2840
2841         /**
2842          * What is the page_latest field for this page?
2843          *
2844          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2845          * @return Int or 0 if the page doesn't exist
2846          */
2847         public function getLatestRevID( $flags = 0 ) {
2848                 if ( $this->mLatestID !== false ) {
2849                         return intval( $this->mLatestID );
2850                 }
2851                 # Calling getArticleID() loads the field from cache as needed
2852                 if ( !$this->getArticleID( $flags ) ) {
2853                         return $this->mLatestID = 0;
2854                 }
2855                 $linkCache = LinkCache::singleton();
2856                 $this->mLatestID = intval( $linkCache->getGoodLinkFieldObj( $this, 'revision' ) );
2857
2858                 return $this->mLatestID;
2859         }
2860
2861         /**
2862          * This clears some fields in this object, and clears any associated
2863          * keys in the "bad links" section of the link cache.
2864          *
2865          * - This is called from WikiPage::doEdit() and WikiPage::insertOn() to allow
2866          * loading of the new page_id. It's also called from
2867          * WikiPage::doDeleteArticle()
2868          *
2869          * @param $newid Int the new Article ID
2870          */
2871         public function resetArticleID( $newid ) {
2872                 $linkCache = LinkCache::singleton();
2873                 $linkCache->clearLink( $this );
2874
2875                 if ( $newid === false ) {
2876                         $this->mArticleID = -1;
2877                 } else {
2878                         $this->mArticleID = intval( $newid );
2879                 }
2880                 $this->mRestrictionsLoaded = false;
2881                 $this->mRestrictions = array();
2882                 $this->mRedirect = null;
2883                 $this->mLength = -1;
2884                 $this->mLatestID = false;
2885                 $this->mEstimateRevisions = null;
2886         }
2887
2888         /**
2889          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
2890          *
2891          * @param $text String containing title to capitalize
2892          * @param $ns int namespace index, defaults to NS_MAIN
2893          * @return String containing capitalized title
2894          */
2895         public static function capitalize( $text, $ns = NS_MAIN ) {
2896                 global $wgContLang;
2897
2898                 if ( MWNamespace::isCapitalized( $ns ) ) {
2899                         return $wgContLang->ucfirst( $text );
2900                 } else {
2901                         return $text;
2902                 }
2903         }
2904
2905         /**
2906          * Secure and split - main initialisation function for this object
2907          *
2908          * Assumes that mDbkeyform has been set, and is urldecoded
2909          * and uses underscores, but not otherwise munged.  This function
2910          * removes illegal characters, splits off the interwiki and
2911          * namespace prefixes, sets the other forms, and canonicalizes
2912          * everything.
2913          *
2914          * @return Bool true on success
2915          */
2916         private function secureAndSplit() {
2917                 global $wgContLang, $wgLocalInterwiki;
2918
2919                 # Initialisation
2920                 $this->mInterwiki = $this->mFragment = '';
2921                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2922
2923                 $dbkey = $this->mDbkeyform;
2924
2925                 # Strip Unicode bidi override characters.
2926                 # Sometimes they slip into cut-n-pasted page titles, where the
2927                 # override chars get included in list displays.
2928                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
2929
2930                 # Clean up whitespace
2931                 # Note: use of the /u option on preg_replace here will cause
2932                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
2933                 # conveniently disabling them.
2934                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
2935                 $dbkey = trim( $dbkey, '_' );
2936
2937                 if ( $dbkey == '' ) {
2938                         return false;
2939                 }
2940
2941                 if ( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2942                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2943                         return false;
2944                 }
2945
2946                 $this->mDbkeyform = $dbkey;
2947
2948                 # Initial colon indicates main namespace rather than specified default
2949                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
2950                 if ( ':' == $dbkey[0] ) {
2951                         $this->mNamespace = NS_MAIN;
2952                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
2953                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
2954                 }
2955
2956                 # Namespace or interwiki prefix
2957                 $firstPass = true;
2958                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
2959                 do {
2960                         $m = array();
2961                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
2962                                 $p = $m[1];
2963                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
2964                                         # Ordinary namespace
2965                                         $dbkey = $m[2];
2966                                         $this->mNamespace = $ns;
2967                                         # For Talk:X pages, check if X has a "namespace" prefix
2968                                         if ( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
2969                                                 if ( $wgContLang->getNsIndex( $x[1] ) ) {
2970                                                         # Disallow Talk:File:x type titles...
2971                                                         return false;
2972                                                 } elseif ( Interwiki::isValidInterwiki( $x[1] ) ) {
2973                                                         # Disallow Talk:Interwiki:x type titles...
2974                                                         return false;
2975                                                 }
2976                                         }
2977                                 } elseif ( Interwiki::isValidInterwiki( $p ) ) {
2978                                         if ( !$firstPass ) {
2979                                                 # Can't make a local interwiki link to an interwiki link.
2980                                                 # That's just crazy!
2981                                                 return false;
2982                                         }
2983
2984                                         # Interwiki link
2985                                         $dbkey = $m[2];
2986                                         $this->mInterwiki = $wgContLang->lc( $p );
2987
2988                                         # Redundant interwiki prefix to the local wiki
2989                                         if ( $wgLocalInterwiki !== false
2990                                                 && 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) )
2991                                         {
2992                                                 if ( $dbkey == '' ) {
2993                                                         # Can't have an empty self-link
2994                                                         return false;
2995                                                 }
2996                                                 $this->mInterwiki = '';
2997                                                 $firstPass = false;
2998                                                 # Do another namespace split...
2999                                                 continue;
3000                                         }
3001
3002                                         # If there's an initial colon after the interwiki, that also
3003                                         # resets the default namespace
3004                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
3005                                                 $this->mNamespace = NS_MAIN;
3006                                                 $dbkey = substr( $dbkey, 1 );
3007                                         }
3008                                 }
3009                                 # If there's no recognized interwiki or namespace,
3010                                 # then let the colon expression be part of the title.
3011                         }
3012                         break;
3013                 } while ( true );
3014
3015                 # We already know that some pages won't be in the database!
3016                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
3017                         $this->mArticleID = 0;
3018                 }
3019                 $fragment = strstr( $dbkey, '#' );
3020                 if ( false !== $fragment ) {
3021                         $this->setFragment( $fragment );
3022                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
3023                         # remove whitespace again: prevents "Foo_bar_#"
3024                         # becoming "Foo_bar_"
3025                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
3026                 }
3027
3028                 # Reject illegal characters.
3029                 $rxTc = self::getTitleInvalidRegex();
3030                 if ( preg_match( $rxTc, $dbkey ) ) {
3031                         return false;
3032                 }
3033
3034                 # Pages with "/./" or "/../" appearing in the URLs will often be un-
3035                 # reachable due to the way web browsers deal with 'relative' URLs.
3036                 # Also, they conflict with subpage syntax.  Forbid them explicitly.
3037                 if ( strpos( $dbkey, '.' ) !== false &&
3038                          ( $dbkey === '.' || $dbkey === '..' ||
3039                            strpos( $dbkey, './' ) === 0  ||
3040                            strpos( $dbkey, '../' ) === 0 ||
3041                            strpos( $dbkey, '/./' ) !== false ||
3042                            strpos( $dbkey, '/../' ) !== false  ||
3043                            substr( $dbkey, -2 ) == '/.' ||
3044                            substr( $dbkey, -3 ) == '/..' ) )
3045                 {
3046                         return false;
3047                 }
3048
3049                 # Magic tilde sequences? Nu-uh!
3050                 if ( strpos( $dbkey, '~~~' ) !== false ) {
3051                         return false;
3052                 }
3053
3054                 # Limit the size of titles to 255 bytes. This is typically the size of the
3055                 # underlying database field. We make an exception for special pages, which
3056                 # don't need to be stored in the database, and may edge over 255 bytes due
3057                 # to subpage syntax for long titles, e.g. [[Special:Block/Long name]]
3058                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
3059                   strlen( $dbkey ) > 512 )
3060                 {
3061                         return false;
3062                 }
3063
3064                 # Normally, all wiki links are forced to have an initial capital letter so [[foo]]
3065                 # and [[Foo]] point to the same place.  Don't force it for interwikis, since the
3066                 # other site might be case-sensitive.
3067                 $this->mUserCaseDBKey = $dbkey;
3068                 if ( $this->mInterwiki == '' ) {
3069                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
3070                 }
3071
3072                 # Can't make a link to a namespace alone... "empty" local links can only be
3073                 # self-links with a fragment identifier.
3074                 if ( $dbkey == '' && $this->mInterwiki == '' && $this->mNamespace != NS_MAIN ) {
3075                         return false;
3076                 }
3077
3078                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
3079                 // IP names are not allowed for accounts, and can only be referring to
3080                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
3081                 // there are numerous ways to present the same IP. Having sp:contribs scan
3082                 // them all is silly and having some show the edits and others not is
3083                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
3084                 $dbkey = ( $this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK )
3085                         ? IP::sanitizeIP( $dbkey )
3086                         : $dbkey;
3087
3088                 // Any remaining initial :s are illegal.
3089                 if ( $dbkey !== '' && ':' == $dbkey[0] ) {
3090                         return false;
3091                 }
3092
3093                 # Fill fields
3094                 $this->mDbkeyform = $dbkey;
3095                 $this->mUrlform = wfUrlencode( $dbkey );
3096
3097                 $this->mTextform = str_replace( '_', ' ', $dbkey );
3098
3099                 return true;
3100         }
3101
3102         /**
3103          * Get an array of Title objects linking to this Title
3104          * Also stores the IDs in the link cache.
3105          *
3106          * WARNING: do not use this function on arbitrary user-supplied titles!
3107          * On heavily-used templates it will max out the memory.
3108          *
3109          * @param $options Array: may be FOR UPDATE
3110          * @param $table String: table name
3111          * @param $prefix String: fields prefix
3112          * @return Array of Title objects linking here
3113          */
3114         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3115                 if ( count( $options ) > 0 ) {
3116                         $db = wfGetDB( DB_MASTER );
3117                 } else {
3118                         $db = wfGetDB( DB_SLAVE );
3119                 }
3120
3121                 $res = $db->select(
3122                         array( 'page', $table ),
3123                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ),
3124                         array(
3125                                 "{$prefix}_from=page_id",
3126                                 "{$prefix}_namespace" => $this->getNamespace(),
3127                                 "{$prefix}_title"     => $this->getDBkey() ),
3128                         __METHOD__,
3129                         $options
3130                 );
3131
3132                 $retVal = array();
3133                 if ( $res->numRows() ) {
3134                         $linkCache = LinkCache::singleton();
3135                         foreach ( $res as $row ) {
3136                                 $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title );
3137                                 if ( $titleObj ) {
3138                                         $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3139                                         $retVal[] = $titleObj;
3140                                 }
3141                         }
3142                 }
3143                 return $retVal;
3144         }
3145
3146         /**
3147          * Get an array of Title objects using this Title as a template
3148          * Also stores the IDs in the link cache.
3149          *
3150          * WARNING: do not use this function on arbitrary user-supplied titles!
3151          * On heavily-used templates it will max out the memory.
3152          *
3153          * @param $options Array: may be FOR UPDATE
3154          * @return Array of Title the Title objects linking here
3155          */
3156         public function getTemplateLinksTo( $options = array() ) {
3157                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
3158         }
3159
3160         /**
3161          * Get an array of Title objects linked from this Title
3162          * Also stores the IDs in the link cache.
3163          *
3164          * WARNING: do not use this function on arbitrary user-supplied titles!
3165          * On heavily-used templates it will max out the memory.
3166          *
3167          * @param $options Array: may be FOR UPDATE
3168          * @param $table String: table name
3169          * @param $prefix String: fields prefix
3170          * @return Array of Title objects linking here
3171          */
3172         public function getLinksFrom( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3173                 $id = $this->getArticleID();
3174
3175                 # If the page doesn't exist; there can't be any link from this page
3176                 if ( !$id ) {
3177                         return array();
3178                 }
3179
3180                 if ( count( $options ) > 0 ) {
3181                         $db = wfGetDB( DB_MASTER );
3182                 } else {
3183                         $db = wfGetDB( DB_SLAVE );
3184                 }
3185
3186                 $namespaceFiled = "{$prefix}_namespace";
3187                 $titleField = "{$prefix}_title";
3188
3189                 $res = $db->select(
3190                         array( $table, 'page' ),
3191                         array( $namespaceFiled, $titleField, 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ),
3192                         array( "{$prefix}_from" => $id ),
3193                         __METHOD__,
3194                         $options,
3195                         array( 'page' => array( 'LEFT JOIN', array( "page_namespace=$namespaceFiled", "page_title=$titleField" ) ) )
3196                 );
3197
3198                 $retVal = array();
3199                 if ( $res->numRows() ) {
3200                         $linkCache = LinkCache::singleton();
3201                         foreach ( $res as $row ) {
3202                                 $titleObj = Title::makeTitle( $row->$namespaceFiled, $row->$titleField );
3203                                 if ( $titleObj ) {
3204                                         if ( $row->page_id ) {
3205                                                 $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3206                                         } else {
3207                                                 $linkCache->addBadLinkObj( $titleObj );
3208                                         }
3209                                         $retVal[] = $titleObj;
3210                                 }
3211                         }
3212                 }
3213                 return $retVal;
3214         }
3215
3216         /**
3217          * Get an array of Title objects used on this Title as a template
3218          * Also stores the IDs in the link cache.
3219          *
3220          * WARNING: do not use this function on arbitrary user-supplied titles!
3221          * On heavily-used templates it will max out the memory.
3222          *
3223          * @param $options Array: may be FOR UPDATE
3224          * @return Array of Title the Title objects used here
3225          */
3226         public function getTemplateLinksFrom( $options = array() ) {
3227                 return $this->getLinksFrom( $options, 'templatelinks', 'tl' );
3228         }
3229
3230         /**
3231          * Get an array of Title objects referring to non-existent articles linked from this page
3232          *
3233          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
3234          * @return Array of Title the Title objects
3235          */
3236         public function getBrokenLinksFrom() {
3237                 if ( $this->getArticleID() == 0 ) {
3238                         # All links from article ID 0 are false positives
3239                         return array();
3240                 }
3241
3242                 $dbr = wfGetDB( DB_SLAVE );
3243                 $res = $dbr->select(
3244                         array( 'page', 'pagelinks' ),
3245                         array( 'pl_namespace', 'pl_title' ),
3246                         array(
3247                                 'pl_from' => $this->getArticleID(),
3248                                 'page_namespace IS NULL'
3249                         ),
3250                         __METHOD__, array(),
3251                         array(
3252                                 'page' => array(
3253                                         'LEFT JOIN',
3254                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
3255                                 )
3256                         )
3257                 );
3258
3259                 $retVal = array();
3260                 foreach ( $res as $row ) {
3261                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
3262                 }
3263                 return $retVal;
3264         }
3265
3266
3267         /**
3268          * Get a list of URLs to purge from the Squid cache when this
3269          * page changes
3270          *
3271          * @return Array of String the URLs
3272          */
3273         public function getSquidURLs() {
3274                 global $wgContLang;
3275
3276                 $urls = array(
3277                         $this->getInternalURL(),
3278                         $this->getInternalURL( 'action=history' )
3279                 );
3280
3281                 // purge variant urls as well
3282                 if ( $wgContLang->hasVariants() ) {
3283                         $variants = $wgContLang->getVariants();
3284                         foreach ( $variants as $vCode ) {
3285                                 $urls[] = $this->getInternalURL( '', $vCode );
3286                         }
3287                 }
3288
3289                 return $urls;
3290         }
3291
3292         /**
3293          * Purge all applicable Squid URLs
3294          */
3295         public function purgeSquid() {
3296                 global $wgUseSquid;
3297                 if ( $wgUseSquid ) {
3298                         $urls = $this->getSquidURLs();
3299                         $u = new SquidUpdate( $urls );
3300                         $u->doUpdate();
3301                 }
3302         }
3303
3304         /**
3305          * Move this page without authentication
3306          *
3307          * @param $nt Title the new page Title
3308          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3309          */
3310         public function moveNoAuth( &$nt ) {
3311                 return $this->moveTo( $nt, false );
3312         }
3313
3314         /**
3315          * Check whether a given move operation would be valid.
3316          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
3317          *
3318          * @param $nt Title the new title
3319          * @param $auth Bool indicates whether $wgUser's permissions
3320          *  should be checked
3321          * @param $reason String is the log summary of the move, used for spam checking
3322          * @return Mixed True on success, getUserPermissionsErrors()-like array on failure
3323          */
3324         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
3325                 global $wgUser;
3326
3327                 $errors = array();
3328                 if ( !$nt ) {
3329                         // Normally we'd add this to $errors, but we'll get
3330                         // lots of syntax errors if $nt is not an object
3331                         return array( array( 'badtitletext' ) );
3332                 }
3333                 if ( $this->equals( $nt ) ) {
3334                         $errors[] = array( 'selfmove' );
3335                 }
3336                 if ( !$this->isMovable() ) {
3337                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
3338                 }
3339                 if ( $nt->getInterwiki() != '' ) {
3340                         $errors[] = array( 'immobile-target-namespace-iw' );
3341                 }
3342                 if ( !$nt->isMovable() ) {
3343                         $errors[] = array( 'immobile-target-namespace', $nt->getNsText() );
3344                 }
3345
3346                 $oldid = $this->getArticleID();
3347                 $newid = $nt->getArticleID();
3348
3349                 if ( strlen( $nt->getDBkey() ) < 1 ) {
3350                         $errors[] = array( 'articleexists' );
3351                 }
3352                 if ( ( $this->getDBkey() == '' ) ||
3353                          ( !$oldid ) ||
3354                          ( $nt->getDBkey() == '' ) ) {
3355                         $errors[] = array( 'badarticleerror' );
3356                 }
3357
3358                 // Image-specific checks
3359                 if ( $this->getNamespace() == NS_FILE ) {
3360                         $errors = array_merge( $errors, $this->validateFileMoveOperation( $nt ) );
3361                 }
3362
3363                 if ( $nt->getNamespace() == NS_FILE && $this->getNamespace() != NS_FILE ) {
3364                         $errors[] = array( 'nonfile-cannot-move-to-file' );
3365                 }
3366
3367                 if ( $auth ) {
3368                         $errors = wfMergeErrorArrays( $errors,
3369                                 $this->getUserPermissionsErrors( 'move', $wgUser ),
3370                                 $this->getUserPermissionsErrors( 'edit', $wgUser ),
3371                                 $nt->getUserPermissionsErrors( 'move-target', $wgUser ),
3372                                 $nt->getUserPermissionsErrors( 'edit', $wgUser ) );
3373                 }
3374
3375                 $match = EditPage::matchSummarySpamRegex( $reason );
3376                 if ( $match !== false ) {
3377                         // This is kind of lame, won't display nice
3378                         $errors[] = array( 'spamprotectiontext' );
3379                 }
3380
3381                 $err = null;
3382                 if ( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
3383                         $errors[] = array( 'hookaborted', $err );
3384                 }
3385
3386                 # The move is allowed only if (1) the target doesn't exist, or
3387                 # (2) the target is a redirect to the source, and has no history
3388                 # (so we can undo bad moves right after they're done).
3389
3390                 if ( 0 != $newid ) { # Target exists; check for validity
3391                         if ( !$this->isValidMoveTarget( $nt ) ) {
3392                                 $errors[] = array( 'articleexists' );
3393                         }
3394                 } else {
3395                         $tp = $nt->getTitleProtection();
3396                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
3397                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
3398                                 $errors[] = array( 'cantmove-titleprotected' );
3399                         }
3400                 }
3401                 if ( empty( $errors ) ) {
3402                         return true;
3403                 }
3404                 return $errors;
3405         }
3406
3407         /**
3408          * Check if the requested move target is a valid file move target
3409          * @param Title $nt Target title
3410          * @return array List of errors
3411          */
3412         protected function validateFileMoveOperation( $nt ) {
3413                 global $wgUser;
3414
3415                 $errors = array();
3416
3417                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is not allowed until below
3418
3419                 $file = wfLocalFile( $this );
3420                 if ( $file->exists() ) {
3421                         if ( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
3422                                 $errors[] = array( 'imageinvalidfilename' );
3423                         }
3424                         if ( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
3425                                 $errors[] = array( 'imagetypemismatch' );
3426                         }
3427                 }
3428
3429                 if ( $nt->getNamespace() != NS_FILE ) {
3430                         $errors[] = array( 'imagenocrossnamespace' );
3431                         // From here we want to do checks on a file object, so if we can't
3432                         // create one, we must return.
3433                         return $errors;
3434                 }
3435
3436                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is allowed below here
3437
3438                 $destFile = wfLocalFile( $nt );
3439                 if ( !$wgUser->isAllowed( 'reupload-shared' ) && !$destFile->exists() && wfFindFile( $nt ) ) {
3440                         $errors[] = array( 'file-exists-sharedrepo' );
3441                 }
3442
3443                 return $errors;
3444         }
3445
3446         /**
3447          * Move a title to a new location
3448          *
3449          * @param $nt Title the new title
3450          * @param $auth Bool indicates whether $wgUser's permissions
3451          *  should be checked
3452          * @param $reason String the reason for the move
3453          * @param $createRedirect Bool Whether to create a redirect from the old title to the new title.
3454          *  Ignored if the user doesn't have the suppressredirect right.
3455          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3456          */
3457         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
3458                 global $wgUser;
3459                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
3460                 if ( is_array( $err ) ) {
3461                         // Auto-block user's IP if the account was "hard" blocked
3462                         $wgUser->spreadAnyEditBlock();
3463                         return $err;
3464                 }
3465
3466                 // If it is a file, move it first.
3467                 // It is done before all other moving stuff is done because it's hard to revert.
3468                 $dbw = wfGetDB( DB_MASTER );
3469                 if ( $this->getNamespace() == NS_FILE ) {
3470                         $file = wfLocalFile( $this );
3471                         if ( $file->exists() ) {
3472                                 $status = $file->move( $nt );
3473                                 if ( !$status->isOk() ) {
3474                                         return $status->getErrorsArray();
3475                                 }
3476                         }
3477                         // Clear RepoGroup process cache
3478                         RepoGroup::singleton()->clearCache( $this );
3479                         RepoGroup::singleton()->clearCache( $nt ); # clear false negative cache
3480                 }
3481
3482                 $dbw->begin( __METHOD__ ); # If $file was a LocalFile, its transaction would have closed our own.
3483                 $pageid = $this->getArticleID( self::GAID_FOR_UPDATE );
3484                 $protected = $this->isProtected();
3485
3486                 // Do the actual move
3487                 $err = $this->moveToInternal( $nt, $reason, $createRedirect );
3488                 if ( is_array( $err ) ) {
3489                         # @todo FIXME: What about the File we have already moved?
3490                         $dbw->rollback( __METHOD__ );
3491                         return $err;
3492                 }
3493
3494                 // Refresh the sortkey for this row.  Be careful to avoid resetting
3495                 // cl_timestamp, which may disturb time-based lists on some sites.
3496                 $prefixes = $dbw->select(
3497                         'categorylinks',
3498                         array( 'cl_sortkey_prefix', 'cl_to' ),
3499                         array( 'cl_from' => $pageid ),
3500                         __METHOD__
3501                 );
3502                 foreach ( $prefixes as $prefixRow ) {
3503                         $prefix = $prefixRow->cl_sortkey_prefix;
3504                         $catTo = $prefixRow->cl_to;
3505                         $dbw->update( 'categorylinks',
3506                                 array(
3507                                         'cl_sortkey' => Collation::singleton()->getSortKey(
3508                                                 $nt->getCategorySortkey( $prefix ) ),
3509                                         'cl_timestamp=cl_timestamp' ),
3510                                 array(
3511                                         'cl_from' => $pageid,
3512                                         'cl_to' => $catTo ),
3513                                 __METHOD__
3514                         );
3515                 }
3516
3517                 $redirid = $this->getArticleID();
3518
3519                 if ( $protected ) {
3520                         # Protect the redirect title as the title used to be...
3521                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
3522                                 array(
3523                                         'pr_page'    => $redirid,
3524                                         'pr_type'    => 'pr_type',
3525                                         'pr_level'   => 'pr_level',
3526                                         'pr_cascade' => 'pr_cascade',
3527                                         'pr_user'    => 'pr_user',
3528                                         'pr_expiry'  => 'pr_expiry'
3529                                 ),
3530                                 array( 'pr_page' => $pageid ),
3531                                 __METHOD__,
3532                                 array( 'IGNORE' )
3533                         );
3534                         # Update the protection log
3535                         $log = new LogPage( 'protect' );
3536                         $comment = wfMsgForContent( 'prot_1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
3537                         if ( $reason ) {
3538                                 $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3539                         }
3540                         // @todo FIXME: $params?
3541                         $log->addEntry( 'move_prot', $nt, $comment, array( $this->getPrefixedText() ) );
3542                 }
3543
3544                 # Update watchlists
3545                 $oldnamespace = $this->getNamespace() & ~1;
3546                 $newnamespace = $nt->getNamespace() & ~1;
3547                 $oldtitle = $this->getDBkey();
3548                 $newtitle = $nt->getDBkey();
3549
3550                 if ( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
3551                         WatchedItem::duplicateEntries( $this, $nt );
3552                 }
3553
3554                 $dbw->commit( __METHOD__ );
3555
3556                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3557                 return true;
3558         }
3559
3560         /**
3561          * Move page to a title which is either a redirect to the
3562          * source page or nonexistent
3563          *
3564          * @param $nt Title the page to move to, which should be a redirect or nonexistent
3565          * @param $reason String The reason for the move
3566          * @param $createRedirect Bool Whether to leave a redirect at the old title.  Ignored
3567          *   if the user doesn't have the suppressredirect right
3568          */
3569         private function moveToInternal( &$nt, $reason = '', $createRedirect = true ) {
3570                 global $wgUser, $wgContLang;
3571
3572                 if ( $nt->exists() ) {
3573                         $moveOverRedirect = true;
3574                         $logType = 'move_redir';
3575                 } else {
3576                         $moveOverRedirect = false;
3577                         $logType = 'move';
3578                 }
3579
3580                 $redirectSuppressed = !$createRedirect && $wgUser->isAllowed( 'suppressredirect' );
3581
3582                 $logEntry = new ManualLogEntry( 'move', $logType );
3583                 $logEntry->setPerformer( $wgUser );
3584                 $logEntry->setTarget( $this );
3585                 $logEntry->setComment( $reason );
3586                 $logEntry->setParameters( array(
3587                         '4::target' => $nt->getPrefixedText(),
3588                         '5::noredir' => $redirectSuppressed ? '1': '0',
3589                 ) );
3590
3591                 $formatter = LogFormatter::newFromEntry( $logEntry );
3592                 $formatter->setContext( RequestContext::newExtraneousContext( $this ) );
3593                 $comment = $formatter->getPlainActionText();
3594                 if ( $reason ) {
3595                         $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3596                 }
3597                 # Truncate for whole multibyte characters.
3598                 $comment = $wgContLang->truncate( $comment, 255 );
3599
3600                 $oldid = $this->getArticleID();
3601
3602                 $dbw = wfGetDB( DB_MASTER );
3603
3604                 $newpage = WikiPage::factory( $nt );
3605
3606                 if ( $moveOverRedirect ) {
3607                         $newid = $nt->getArticleID();
3608
3609                         # Delete the old redirect. We don't save it to history since
3610                         # by definition if we've got here it's rather uninteresting.
3611                         # We have to remove it so that the next step doesn't trigger
3612                         # a conflict on the unique namespace+title index...
3613                         $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3614
3615                         $newpage->doDeleteUpdates( $newid );
3616                 }
3617
3618                 # Save a null revision in the page's history notifying of the move
3619                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3620                 if ( !is_object( $nullRevision ) ) {
3621                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3622                 }
3623                 $nullRevId = $nullRevision->insertOn( $dbw );
3624
3625                 # Change the name of the target page:
3626                 $dbw->update( 'page',
3627                         /* SET */ array(
3628                                 'page_namespace' => $nt->getNamespace(),
3629                                 'page_title'     => $nt->getDBkey(),
3630                         ),
3631                         /* WHERE */ array( 'page_id' => $oldid ),
3632                         __METHOD__
3633                 );
3634
3635                 $this->resetArticleID( 0 );
3636                 $nt->resetArticleID( $oldid );
3637
3638                 $newpage->updateRevisionOn( $dbw, $nullRevision );
3639
3640                 wfRunHooks( 'NewRevisionFromEditComplete',
3641                         array( $newpage, $nullRevision, $nullRevision->getParentId(), $wgUser ) );
3642
3643                 $newpage->doEditUpdates( $nullRevision, $wgUser, array( 'changed' => false ) );
3644
3645                 if ( !$moveOverRedirect ) {
3646                         WikiPage::onArticleCreate( $nt );
3647                 }
3648
3649                 # Recreate the redirect, this time in the other direction.
3650                 if ( $redirectSuppressed ) {
3651                         WikiPage::onArticleDelete( $this );
3652                 } else {
3653                         $mwRedir = MagicWord::get( 'redirect' );
3654                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3655                         $redirectArticle = WikiPage::factory( $this );
3656                         $newid = $redirectArticle->insertOn( $dbw );
3657                         if ( $newid ) { // sanity
3658                                 $redirectRevision = new Revision( array(
3659                                         'page'    => $newid,
3660                                         'comment' => $comment,
3661                                         'text'    => $redirectText ) );
3662                                 $redirectRevision->insertOn( $dbw );
3663                                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3664
3665                                 wfRunHooks( 'NewRevisionFromEditComplete',
3666                                         array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3667
3668                                 $redirectArticle->doEditUpdates( $redirectRevision, $wgUser, array( 'created' => true ) );
3669                         }
3670                 }
3671
3672                 # Log the move
3673                 $logid = $logEntry->insert();
3674                 $logEntry->publish( $logid );
3675         }
3676
3677         /**
3678          * Move this page's subpages to be subpages of $nt
3679          *
3680          * @param $nt Title Move target
3681          * @param $auth bool Whether $wgUser's permissions should be checked
3682          * @param $reason string The reason for the move
3683          * @param $createRedirect bool Whether to create redirects from the old subpages to
3684          *     the new ones Ignored if the user doesn't have the 'suppressredirect' right
3685          * @return mixed array with old page titles as keys, and strings (new page titles) or
3686          *     arrays (errors) as values, or an error array with numeric indices if no pages
3687          *     were moved
3688          */
3689         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3690                 global $wgMaximumMovedPages;
3691                 // Check permissions
3692                 if ( !$this->userCan( 'move-subpages' ) ) {
3693                         return array( 'cant-move-subpages' );
3694                 }
3695                 // Do the source and target namespaces support subpages?
3696                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
3697                         return array( 'namespace-nosubpages',
3698                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3699                 }
3700                 if ( !MWNamespace::hasSubpages( $nt->getNamespace() ) ) {
3701                         return array( 'namespace-nosubpages',
3702                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3703                 }
3704
3705                 $subpages = $this->getSubpages( $wgMaximumMovedPages + 1 );
3706                 $retval = array();
3707                 $count = 0;
3708                 foreach ( $subpages as $oldSubpage ) {
3709                         $count++;
3710                         if ( $count > $wgMaximumMovedPages ) {
3711                                 $retval[$oldSubpage->getPrefixedTitle()] =
3712                                                 array( 'movepage-max-pages',
3713                                                         $wgMaximumMovedPages );
3714                                 break;
3715                         }
3716
3717                         // We don't know whether this function was called before
3718                         // or after moving the root page, so check both
3719                         // $this and $nt
3720                         if ( $oldSubpage->getArticleID() == $this->getArticleID() ||
3721                                         $oldSubpage->getArticleID() == $nt->getArticleID() )
3722                         {
3723                                 // When moving a page to a subpage of itself,
3724                                 // don't move it twice
3725                                 continue;
3726                         }
3727                         $newPageName = preg_replace(
3728                                         '#^' . preg_quote( $this->getDBkey(), '#' ) . '#',
3729                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3730                                         $oldSubpage->getDBkey() );
3731                         if ( $oldSubpage->isTalkPage() ) {
3732                                 $newNs = $nt->getTalkPage()->getNamespace();
3733                         } else {
3734                                 $newNs = $nt->getSubjectPage()->getNamespace();
3735                         }
3736                         # Bug 14385: we need makeTitleSafe because the new page names may
3737                         # be longer than 255 characters.
3738                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3739
3740                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3741                         if ( $success === true ) {
3742                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3743                         } else {
3744                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3745                         }
3746                 }
3747                 return $retval;
3748         }
3749
3750         /**
3751          * Checks if this page is just a one-rev redirect.
3752          * Adds lock, so don't use just for light purposes.
3753          *
3754          * @return Bool
3755          */
3756         public function isSingleRevRedirect() {
3757                 $dbw = wfGetDB( DB_MASTER );
3758                 # Is it a redirect?
3759                 $row = $dbw->selectRow( 'page',
3760                         array( 'page_is_redirect', 'page_latest', 'page_id' ),
3761                         $this->pageCond(),
3762                         __METHOD__,
3763                         array( 'FOR UPDATE' )
3764                 );
3765                 # Cache some fields we may want
3766                 $this->mArticleID = $row ? intval( $row->page_id ) : 0;
3767                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3768                 $this->mLatestID = $row ? intval( $row->page_latest ) : false;
3769                 if ( !$this->mRedirect ) {
3770                         return false;
3771                 }
3772                 # Does the article have a history?
3773                 $row = $dbw->selectField( array( 'page', 'revision' ),
3774                         'rev_id',
3775                         array( 'page_namespace' => $this->getNamespace(),
3776                                 'page_title' => $this->getDBkey(),
3777                                 'page_id=rev_page',
3778                                 'page_latest != rev_id'
3779                         ),
3780                         __METHOD__,
3781                         array( 'FOR UPDATE' )
3782                 );
3783                 # Return true if there was no history
3784                 return ( $row === false );
3785         }
3786
3787         /**
3788          * Checks if $this can be moved to a given Title
3789          * - Selects for update, so don't call it unless you mean business
3790          *
3791          * @param $nt Title the new title to check
3792          * @return Bool
3793          */
3794         public function isValidMoveTarget( $nt ) {
3795                 # Is it an existing file?
3796                 if ( $nt->getNamespace() == NS_FILE ) {
3797                         $file = wfLocalFile( $nt );
3798                         if ( $file->exists() ) {
3799                                 wfDebug( __METHOD__ . ": file exists\n" );
3800                                 return false;
3801                         }
3802                 }
3803                 # Is it a redirect with no history?
3804                 if ( !$nt->isSingleRevRedirect() ) {
3805                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3806                         return false;
3807                 }
3808                 # Get the article text
3809                 $rev = Revision::newFromTitle( $nt );
3810                 if( !is_object( $rev ) ){
3811                         return false;
3812                 }
3813                 $text = $rev->getText();
3814                 # Does the redirect point to the source?
3815                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3816                 $m = array();
3817                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
3818                         $redirTitle = Title::newFromText( $m[1] );
3819                         if ( !is_object( $redirTitle ) ||
3820                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3821                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
3822                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3823                                 return false;
3824                         }
3825                 } else {
3826                         # Fail safe
3827                         wfDebug( __METHOD__ . ": failsafe\n" );
3828                         return false;
3829                 }
3830                 return true;
3831         }
3832
3833         /**
3834          * Get categories to which this Title belongs and return an array of
3835          * categories' names.
3836          *
3837          * @return Array of parents in the form:
3838          *        $parent => $currentarticle
3839          */
3840         public function getParentCategories() {
3841                 global $wgContLang;
3842
3843                 $data = array();
3844
3845                 $titleKey = $this->getArticleID();
3846
3847                 if ( $titleKey === 0 ) {
3848                         return $data;
3849                 }
3850
3851                 $dbr = wfGetDB( DB_SLAVE );
3852
3853                 $res = $dbr->select( 'categorylinks', '*',
3854                         array(
3855                                 'cl_from' => $titleKey,
3856                         ),
3857                         __METHOD__,
3858                         array()
3859                 );
3860
3861                 if ( $dbr->numRows( $res ) > 0 ) {
3862                         foreach ( $res as $row ) {
3863                                 // $data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
3864                                 $data[$wgContLang->getNSText( NS_CATEGORY ) . ':' . $row->cl_to] = $this->getFullText();
3865                         }
3866                 }
3867                 return $data;
3868         }
3869
3870         /**
3871          * Get a tree of parent categories
3872          *
3873          * @param $children Array with the children in the keys, to check for circular refs
3874          * @return Array Tree of parent categories
3875          */
3876         public function getParentCategoryTree( $children = array() ) {
3877                 $stack = array();
3878                 $parents = $this->getParentCategories();
3879
3880                 if ( $parents ) {
3881                         foreach ( $parents as $parent => $current ) {
3882                                 if ( array_key_exists( $parent, $children ) ) {
3883                                         # Circular reference
3884                                         $stack[$parent] = array();
3885                                 } else {
3886                                         $nt = Title::newFromText( $parent );
3887                                         if ( $nt ) {
3888                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array( $parent => 1 ) );
3889                                         }
3890                                 }
3891                         }
3892                 }
3893
3894                 return $stack;
3895         }
3896
3897         /**
3898          * Get an associative array for selecting this title from
3899          * the "page" table
3900          *
3901          * @return Array suitable for the $where parameter of DB::select()
3902          */
3903         public function pageCond() {
3904                 if ( $this->mArticleID > 0 ) {
3905                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
3906                         return array( 'page_id' => $this->mArticleID );
3907                 } else {
3908                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
3909                 }
3910         }
3911
3912         /**
3913          * Get the revision ID of the previous revision
3914          *
3915          * @param $revId Int Revision ID. Get the revision that was before this one.
3916          * @param $flags Int Title::GAID_FOR_UPDATE
3917          * @return Int|Bool Old revision ID, or FALSE if none exists
3918          */
3919         public function getPreviousRevisionID( $revId, $flags = 0 ) {
3920                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3921                 $revId = $db->selectField( 'revision', 'rev_id',
3922                         array(
3923                                 'rev_page' => $this->getArticleID( $flags ),
3924                                 'rev_id < ' . intval( $revId )
3925                         ),
3926                         __METHOD__,
3927                         array( 'ORDER BY' => 'rev_id DESC' )
3928                 );
3929
3930                 if ( $revId === false ) {
3931                         return false;
3932                 } else {
3933                         return intval( $revId );
3934                 }
3935         }
3936
3937         /**
3938          * Get the revision ID of the next revision
3939          *
3940          * @param $revId Int Revision ID. Get the revision that was after this one.
3941          * @param $flags Int Title::GAID_FOR_UPDATE
3942          * @return Int|Bool Next revision ID, or FALSE if none exists
3943          */
3944         public function getNextRevisionID( $revId, $flags = 0 ) {
3945                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3946                 $revId = $db->selectField( 'revision', 'rev_id',
3947                         array(
3948                                 'rev_page' => $this->getArticleID( $flags ),
3949                                 'rev_id > ' . intval( $revId )
3950                         ),
3951                         __METHOD__,
3952                         array( 'ORDER BY' => 'rev_id' )
3953                 );
3954
3955                 if ( $revId === false ) {
3956                         return false;
3957                 } else {
3958                         return intval( $revId );
3959                 }
3960         }
3961
3962         /**
3963          * Get the first revision of the page
3964          *
3965          * @param $flags Int Title::GAID_FOR_UPDATE
3966          * @return Revision|Null if page doesn't exist
3967          */
3968         public function getFirstRevision( $flags = 0 ) {
3969                 $pageId = $this->getArticleID( $flags );
3970                 if ( $pageId ) {
3971                         $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3972                         $row = $db->selectRow( 'revision', '*',
3973                                 array( 'rev_page' => $pageId ),
3974                                 __METHOD__,
3975                                 array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
3976                         );
3977                         if ( $row ) {
3978                                 return new Revision( $row );
3979                         }
3980                 }
3981                 return null;
3982         }
3983
3984         /**
3985          * Get the oldest revision timestamp of this page
3986          *
3987          * @param $flags Int Title::GAID_FOR_UPDATE
3988          * @return String: MW timestamp
3989          */
3990         public function getEarliestRevTime( $flags = 0 ) {
3991                 $rev = $this->getFirstRevision( $flags );
3992                 return $rev ? $rev->getTimestamp() : null;
3993         }
3994
3995         /**
3996          * Check if this is a new page
3997          *
3998          * @return bool
3999          */
4000         public function isNewPage() {
4001                 $dbr = wfGetDB( DB_SLAVE );
4002                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
4003         }
4004
4005         /**
4006          * Check whether the number of revisions of this page surpasses $wgDeleteRevisionsLimit
4007          *
4008          * @return bool
4009          */
4010         public function isBigDeletion() {
4011                 global $wgDeleteRevisionsLimit;
4012
4013                 if ( !$wgDeleteRevisionsLimit ) {
4014                         return false;
4015                 }
4016
4017                 $revCount = $this->estimateRevisionCount();
4018                 return $revCount > $wgDeleteRevisionsLimit;
4019         }
4020
4021         /**
4022          * Get the  approximate revision count of this page.
4023          *
4024          * @return int
4025          */
4026         public function estimateRevisionCount() {
4027                 if ( !$this->exists() ) {
4028                         return 0;
4029                 }
4030
4031                 if ( $this->mEstimateRevisions === null ) {
4032                         $dbr = wfGetDB( DB_SLAVE );
4033                         $this->mEstimateRevisions = $dbr->estimateRowCount( 'revision', '*',
4034                                 array( 'rev_page' => $this->getArticleID() ), __METHOD__ );
4035                 }
4036
4037                 return $this->mEstimateRevisions;
4038         }
4039
4040         /**
4041          * Get the number of revisions between the given revision.
4042          * Used for diffs and other things that really need it.
4043          *
4044          * @param $old int|Revision Old revision or rev ID (first before range)
4045          * @param $new int|Revision New revision or rev ID (first after range)
4046          * @return Int Number of revisions between these revisions.
4047          */
4048         public function countRevisionsBetween( $old, $new ) {
4049                 if ( !( $old instanceof Revision ) ) {
4050                         $old = Revision::newFromTitle( $this, (int)$old );
4051                 }
4052                 if ( !( $new instanceof Revision ) ) {
4053                         $new = Revision::newFromTitle( $this, (int)$new );
4054                 }
4055                 if ( !$old || !$new ) {
4056                         return 0; // nothing to compare
4057                 }
4058                 $dbr = wfGetDB( DB_SLAVE );
4059                 return (int)$dbr->selectField( 'revision', 'count(*)',
4060                         array(
4061                                 'rev_page' => $this->getArticleID(),
4062                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4063                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4064                         ),
4065                         __METHOD__
4066                 );
4067         }
4068
4069         /**
4070          * Get the number of authors between the given revision IDs.
4071          * Used for diffs and other things that really need it.
4072          *
4073          * @param $old int|Revision Old revision or rev ID (first before range)
4074          * @param $new int|Revision New revision or rev ID (first after range)
4075          * @param $limit Int Maximum number of authors
4076          * @return Int Number of revision authors between these revisions.
4077          */
4078         public function countAuthorsBetween( $old, $new, $limit ) {
4079                 if ( !( $old instanceof Revision ) ) {
4080                         $old = Revision::newFromTitle( $this, (int)$old );
4081                 }
4082                 if ( !( $new instanceof Revision ) ) {
4083                         $new = Revision::newFromTitle( $this, (int)$new );
4084                 }
4085                 if ( !$old || !$new ) {
4086                         return 0; // nothing to compare
4087                 }
4088                 $dbr = wfGetDB( DB_SLAVE );
4089                 $res = $dbr->select( 'revision', 'DISTINCT rev_user_text',
4090                         array(
4091                                 'rev_page' => $this->getArticleID(),
4092                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4093                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4094                         ), __METHOD__,
4095                         array( 'LIMIT' => $limit + 1 ) // add one so caller knows it was truncated
4096                 );
4097                 return (int)$dbr->numRows( $res );
4098         }
4099
4100         /**
4101          * Compare with another title.
4102          *
4103          * @param $title Title
4104          * @return Bool
4105          */
4106         public function equals( Title $title ) {
4107                 // Note: === is necessary for proper matching of number-like titles.
4108                 return $this->getInterwiki() === $title->getInterwiki()
4109                         && $this->getNamespace() == $title->getNamespace()
4110                         && $this->getDBkey() === $title->getDBkey();
4111         }
4112
4113         /**
4114          * Check if this title is a subpage of another title
4115          *
4116          * @param $title Title
4117          * @return Bool
4118          */
4119         public function isSubpageOf( Title $title ) {
4120                 return $this->getInterwiki() === $title->getInterwiki()
4121                         && $this->getNamespace() == $title->getNamespace()
4122                         && strpos( $this->getDBkey(), $title->getDBkey() . '/' ) === 0;
4123         }
4124
4125         /**
4126          * Check if page exists.  For historical reasons, this function simply
4127          * checks for the existence of the title in the page table, and will
4128          * thus return false for interwiki links, special pages and the like.
4129          * If you want to know if a title can be meaningfully viewed, you should
4130          * probably call the isKnown() method instead.
4131          *
4132          * @return Bool
4133          */
4134         public function exists() {
4135                 return $this->getArticleID() != 0;
4136         }
4137
4138         /**
4139          * Should links to this title be shown as potentially viewable (i.e. as
4140          * "bluelinks"), even if there's no record by this title in the page
4141          * table?
4142          *
4143          * This function is semi-deprecated for public use, as well as somewhat
4144          * misleadingly named.  You probably just want to call isKnown(), which
4145          * calls this function internally.
4146          *
4147          * (ISSUE: Most of these checks are cheap, but the file existence check
4148          * can potentially be quite expensive.  Including it here fixes a lot of
4149          * existing code, but we might want to add an optional parameter to skip
4150          * it and any other expensive checks.)
4151          *
4152          * @return Bool
4153          */
4154         public function isAlwaysKnown() {
4155                 $isKnown = null;
4156
4157                 /**
4158                  * Allows overriding default behaviour for determining if a page exists.
4159                  * If $isKnown is kept as null, regular checks happen. If it's
4160                  * a boolean, this value is returned by the isKnown method.
4161                  *
4162                  * @since 1.20
4163                  *
4164                  * @param Title $title
4165                  * @param boolean|null $isKnown
4166                  */
4167                 wfRunHooks( 'TitleIsAlwaysKnown', array( $this, &$isKnown ) );
4168
4169                 if ( !is_null( $isKnown ) ) {
4170                         return $isKnown;
4171                 }
4172
4173                 if ( $this->mInterwiki != '' ) {
4174                         return true;  // any interwiki link might be viewable, for all we know
4175                 }
4176
4177                 switch( $this->mNamespace ) {
4178                         case NS_MEDIA:
4179                         case NS_FILE:
4180                                 // file exists, possibly in a foreign repo
4181                                 return (bool)wfFindFile( $this );
4182                         case NS_SPECIAL:
4183                                 // valid special page
4184                                 return SpecialPageFactory::exists( $this->getDBkey() );
4185                         case NS_MAIN:
4186                                 // selflink, possibly with fragment
4187                                 return $this->mDbkeyform == '';
4188                         case NS_MEDIAWIKI:
4189                                 // known system message
4190                                 return $this->hasSourceText() !== false;
4191                         default:
4192                                 return false;
4193                 }
4194         }
4195
4196         /**
4197          * Does this title refer to a page that can (or might) be meaningfully
4198          * viewed?  In particular, this function may be used to determine if
4199          * links to the title should be rendered as "bluelinks" (as opposed to
4200          * "redlinks" to non-existent pages).
4201          * Adding something else to this function will cause inconsistency
4202          * since LinkHolderArray calls isAlwaysKnown() and does its own
4203          * page existence check.
4204          *
4205          * @return Bool
4206          */
4207         public function isKnown() {
4208                 return $this->isAlwaysKnown() || $this->exists();
4209         }
4210
4211         /**
4212          * Does this page have source text?
4213          *
4214          * @return Boolean
4215          */
4216         public function hasSourceText() {
4217                 if ( $this->exists() ) {
4218                         return true;
4219                 }
4220
4221                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
4222                         // If the page doesn't exist but is a known system message, default
4223                         // message content will be displayed, same for language subpages-
4224                         // Use always content language to avoid loading hundreds of languages
4225                         // to get the link color.
4226                         global $wgContLang;
4227                         list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4228                         $message = wfMessage( $name )->inLanguage( $wgContLang )->useDatabase( false );
4229                         return $message->exists();
4230                 }
4231
4232                 return false;
4233         }
4234
4235         /**
4236          * Get the default message text or false if the message doesn't exist
4237          *
4238          * @return String or false
4239          */
4240         public function getDefaultMessageText() {
4241                 global $wgContLang;
4242
4243                 if ( $this->getNamespace() != NS_MEDIAWIKI ) { // Just in case
4244                         return false;
4245                 }
4246
4247                 list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4248                 $message = wfMessage( $name )->inLanguage( $lang )->useDatabase( false );
4249
4250                 if ( $message->exists() ) {
4251                         return $message->plain();
4252                 } else {
4253                         return false;
4254                 }
4255         }
4256
4257         /**
4258          * Updates page_touched for this page; called from LinksUpdate.php
4259          *
4260          * @return Bool true if the update succeded
4261          */
4262         public function invalidateCache() {
4263                 if ( wfReadOnly() ) {
4264                         return false;
4265                 }
4266                 $dbw = wfGetDB( DB_MASTER );
4267                 $success = $dbw->update(
4268                         'page',
4269                         array( 'page_touched' => $dbw->timestamp() ),
4270                         $this->pageCond(),
4271                         __METHOD__
4272                 );
4273                 HTMLFileCache::clearFileCache( $this );
4274                 return $success;
4275         }
4276
4277         /**
4278          * Update page_touched timestamps and send squid purge messages for
4279          * pages linking to this title. May be sent to the job queue depending
4280          * on the number of links. Typically called on create and delete.
4281          */
4282         public function touchLinks() {
4283                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
4284                 $u->doUpdate();
4285
4286                 if ( $this->getNamespace() == NS_CATEGORY ) {
4287                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
4288                         $u->doUpdate();
4289                 }
4290         }
4291
4292         /**
4293          * Get the last touched timestamp
4294          *
4295          * @param $db DatabaseBase: optional db
4296          * @return String last-touched timestamp
4297          */
4298         public function getTouched( $db = null ) {
4299                 $db = isset( $db ) ? $db : wfGetDB( DB_SLAVE );
4300                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
4301                 return $touched;
4302         }
4303
4304         /**
4305          * Get the timestamp when this page was updated since the user last saw it.
4306          *
4307          * @param $user User
4308          * @return String|Null
4309          */
4310         public function getNotificationTimestamp( $user = null ) {
4311                 global $wgUser, $wgShowUpdatedMarker;
4312                 // Assume current user if none given
4313                 if ( !$user ) {
4314                         $user = $wgUser;
4315                 }
4316                 // Check cache first
4317                 $uid = $user->getId();
4318                 // avoid isset here, as it'll return false for null entries
4319                 if ( array_key_exists( $uid, $this->mNotificationTimestamp ) ) {
4320                         return $this->mNotificationTimestamp[$uid];
4321                 }
4322                 if ( !$uid || !$wgShowUpdatedMarker ) {
4323                         return $this->mNotificationTimestamp[$uid] = false;
4324                 }
4325                 // Don't cache too much!
4326                 if ( count( $this->mNotificationTimestamp ) >= self::CACHE_MAX ) {
4327                         $this->mNotificationTimestamp = array();
4328                 }
4329                 $dbr = wfGetDB( DB_SLAVE );
4330                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
4331                         'wl_notificationtimestamp',
4332                         array(
4333                                 'wl_user' => $user->getId(),
4334                                 'wl_namespace' => $this->getNamespace(),
4335                                 'wl_title' => $this->getDBkey(),
4336                         ),
4337                         __METHOD__
4338                 );
4339                 return $this->mNotificationTimestamp[$uid];
4340         }
4341
4342         /**
4343          * Generate strings used for xml 'id' names in monobook tabs
4344          *
4345          * @param $prepend string defaults to 'nstab-'
4346          * @return String XML 'id' name
4347          */
4348         public function getNamespaceKey( $prepend = 'nstab-' ) {
4349                 global $wgContLang;
4350                 // Gets the subject namespace if this title
4351                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
4352                 // Checks if cononical namespace name exists for namespace
4353                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
4354                         // Uses canonical namespace name
4355                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
4356                 } else {
4357                         // Uses text of namespace
4358                         $namespaceKey = $this->getSubjectNsText();
4359                 }
4360                 // Makes namespace key lowercase
4361                 $namespaceKey = $wgContLang->lc( $namespaceKey );
4362                 // Uses main
4363                 if ( $namespaceKey == '' ) {
4364                         $namespaceKey = 'main';
4365                 }
4366                 // Changes file to image for backwards compatibility
4367                 if ( $namespaceKey == 'file' ) {
4368                         $namespaceKey = 'image';
4369                 }
4370                 return $prepend . $namespaceKey;
4371         }
4372
4373         /**
4374          * Get all extant redirects to this Title
4375          *
4376          * @param $ns Int|Null Single namespace to consider; NULL to consider all namespaces
4377          * @return Array of Title redirects to this title
4378          */
4379         public function getRedirectsHere( $ns = null ) {
4380                 $redirs = array();
4381
4382                 $dbr = wfGetDB( DB_SLAVE );
4383                 $where = array(
4384                         'rd_namespace' => $this->getNamespace(),
4385                         'rd_title' => $this->getDBkey(),
4386                         'rd_from = page_id'
4387                 );
4388                 if ( !is_null( $ns ) ) {
4389                         $where['page_namespace'] = $ns;
4390                 }
4391
4392                 $res = $dbr->select(
4393                         array( 'redirect', 'page' ),
4394                         array( 'page_namespace', 'page_title' ),
4395                         $where,
4396                         __METHOD__
4397                 );
4398
4399                 foreach ( $res as $row ) {
4400                         $redirs[] = self::newFromRow( $row );
4401                 }
4402                 return $redirs;
4403         }
4404
4405         /**
4406          * Check if this Title is a valid redirect target
4407          *
4408          * @return Bool
4409          */
4410         public function isValidRedirectTarget() {
4411                 global $wgInvalidRedirectTargets;
4412
4413                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
4414                 if ( $this->isSpecial( 'Userlogout' ) ) {
4415                         return false;
4416                 }
4417
4418                 foreach ( $wgInvalidRedirectTargets as $target ) {
4419                         if ( $this->isSpecial( $target ) ) {
4420                                 return false;
4421                         }
4422                 }
4423
4424                 return true;
4425         }
4426
4427         /**
4428          * Get a backlink cache object
4429          *
4430          * @return BacklinkCache
4431          */
4432         function getBacklinkCache() {
4433                 if ( is_null( $this->mBacklinkCache ) ) {
4434                         $this->mBacklinkCache = new BacklinkCache( $this );
4435                 }
4436                 return $this->mBacklinkCache;
4437         }
4438
4439         /**
4440          * Whether the magic words __INDEX__ and __NOINDEX__ function for  this page.
4441          *
4442          * @return Boolean
4443          */
4444         public function canUseNoindex() {
4445                 global $wgContentNamespaces, $wgExemptFromUserRobotsControl;
4446
4447                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
4448                         ? $wgContentNamespaces
4449                         : $wgExemptFromUserRobotsControl;
4450
4451                 return !in_array( $this->mNamespace, $bannedNamespaces );
4452
4453         }
4454
4455         /**
4456          * Returns the raw sort key to be used for categories, with the specified
4457          * prefix.  This will be fed to Collation::getSortKey() to get a
4458          * binary sortkey that can be used for actual sorting.
4459          *
4460          * @param $prefix string The prefix to be used, specified using
4461          *   {{defaultsort:}} or like [[Category:Foo|prefix]].  Empty for no
4462          *   prefix.
4463          * @return string
4464          */
4465         public function getCategorySortkey( $prefix = '' ) {
4466                 $unprefixed = $this->getText();
4467
4468                 // Anything that uses this hook should only depend
4469                 // on the Title object passed in, and should probably
4470                 // tell the users to run updateCollations.php --force
4471                 // in order to re-sort existing category relations.
4472                 wfRunHooks( 'GetDefaultSortkey', array( $this, &$unprefixed ) );
4473                 if ( $prefix !== '' ) {
4474                         # Separate with a line feed, so the unprefixed part is only used as
4475                         # a tiebreaker when two pages have the exact same prefix.
4476                         # In UCA, tab is the only character that can sort above LF
4477                         # so we strip both of them from the original prefix.
4478                         $prefix = strtr( $prefix, "\n\t", '  ' );
4479                         return "$prefix\n$unprefixed";
4480                 }
4481                 return $unprefixed;
4482         }
4483
4484         /**
4485          * Get the language in which the content of this page is written.
4486          * Defaults to $wgContLang, but in certain cases it can be e.g.
4487          * $wgLang (such as special pages, which are in the user language).
4488          *
4489          * @since 1.18
4490          * @return Language
4491          */
4492         public function getPageLanguage() {
4493                 global $wgLang;
4494                 if ( $this->isSpecialPage() ) {
4495                         // special pages are in the user language
4496                         return $wgLang;
4497                 } elseif ( $this->isCssOrJsPage() || $this->isCssJsSubpage() ) {
4498                         // css/js should always be LTR and is, in fact, English
4499                         return wfGetLangObj( 'en' );
4500                 } elseif ( $this->getNamespace() == NS_MEDIAWIKI ) {
4501                         // Parse mediawiki messages with correct target language
4502                         list( /* $unused */, $lang ) = MessageCache::singleton()->figureMessage( $this->getText() );
4503                         return wfGetLangObj( $lang );
4504                 }
4505                 global $wgContLang;
4506                 // If nothing special, it should be in the wiki content language
4507                 $pageLang = $wgContLang;
4508                 // Hook at the end because we don't want to override the above stuff
4509                 wfRunHooks( 'PageContentLanguage', array( $this, &$pageLang, $wgLang ) );
4510                 return wfGetLangObj( $pageLang );
4511         }
4512 }