includes/Title.php

   1 <?php
   2 /**
   3  * See title.txt
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 /**
  24  * Represents a title within MediaWiki.
  25  * Optionally may contain an interwiki designation or namespace.
  26  * @note This class can fetch various kinds of data from the database;
  27  *       however, it does so inefficiently.
  28  *
  29  * @internal documentation reviewed 15 Mar 2010
  30  */
  31 class Title {
  32         /** @name Static cache variables */
  33         // @{
  34         static private $titleCache = array();
  35         // @}
  36
  37         /**
  38          * Title::newFromText maintains a cache to avoid expensive re-normalization of
  39          * commonly used titles. On a batch operation this can become a memory leak
  40          * if not bounded. After hitting this many titles reset the cache.
  41          */
  42         const CACHE_MAX = 1000;
  43
  44         /**
  45          * Used to be GAID_FOR_UPDATE define. Used with getArticleID() and friends
  46          * to use the master DB
  47          */
  48         const GAID_FOR_UPDATE = 1;
  49
  50         /**
  51          * @name Private member variables
  52          * Please use the accessor functions instead.
  53          * @private
  54          */
  55         // @{
  56
  57         var $mTextform = '';              // /< Text form (spaces not underscores) of the main part
  58         var $mUrlform = '';               // /< URL-encoded form of the main part
  59         var $mDbkeyform = '';             // /< Main part with underscores
  60         var $mUserCaseDBKey;              // /< DB key with the initial letter in the case specified by the user
  61         var $mNamespace = NS_MAIN;        // /< Namespace index, i.e. one of the NS_xxxx constants
  62         var $mInterwiki = '';             // /< Interwiki prefix (or null string)
  63         var $mFragment;                   // /< Title fragment (i.e. the bit after the #)
  64         var $mArticleID = -1;             // /< Article ID, fetched from the link cache on demand
  65         var $mLatestID = false;           // /< ID of most recent revision
  66         private $mEstimateRevisions;      // /< Estimated number of revisions; null of not loaded
  67         var $mRestrictions = array();     // /< Array of groups allowed to edit this article
  68         var $mOldRestrictions = false;
  69         var $mCascadeRestriction;         ///< Cascade restrictions on this page to included templates and images?
  70         var $mCascadingRestrictions;      // Caching the results of getCascadeProtectionSources
  71         var $mRestrictionsExpiry = array(); ///< When do the restrictions on this page expire?
  72         var $mHasCascadingRestrictions;   ///< Are cascading restrictions in effect on this page?
  73         var $mCascadeSources;             ///< Where are the cascading restrictions coming from on this page?
  74         var $mRestrictionsLoaded = false; ///< Boolean for initialisation on demand
  75         var $mPrefixedText;               ///< Text form including namespace/interwiki, initialised on demand
  76         var $mTitleProtection;            ///< Cached value for getTitleProtection (create protection)
  77         # Don't change the following default, NS_MAIN is hardcoded in several
  78         # places.  See bug 696.
  79         var $mDefaultNamespace = NS_MAIN; // /< Namespace index when there is no namespace
  80                                                                           # Zero except in {{transclusion}} tags
  81         var $mWatched = null;             // /< Is $wgUser watching this page? null if unfilled, accessed through userIsWatching()
  82         var $mLength = -1;                // /< The page length, 0 for special pages
  83         var $mRedirect = null;            // /< Is the article at this title a redirect?
  84         var $mNotificationTimestamp = array(); // /< Associative array of user ID -> timestamp/false
  85         var $mBacklinkCache = null;       // /< Cache of links to this title
  86         // @}
  87
  88
  89         /**
  90          * Constructor
  91          */
  92         /*protected*/ function __construct() { }
  93
  94         /**
  95          * Create a new Title from a prefixed DB key
  96          *
  97          * @param $key String the database key, which has underscores
  98          *      instead of spaces, possibly including namespace and
  99          *      interwiki prefixes
 100          * @return Title, or NULL on an error
 101          */
 102         public static function newFromDBkey( $key ) {
 103                 $t = new Title();
 104                 $t->mDbkeyform = $key;
 105                 if ( $t->secureAndSplit() ) {
 106                         return $t;
 107                 } else {
 108                         return null;
 109                 }
 110         }
 111
 112         /**
 113          * Create a new Title from text, such as what one would find in a link. De-
 114          * codes any HTML entities in the text.
 115          *
 116          * @param $text String the link text; spaces, prefixes, and an
 117          *   initial ':' indicating the main namespace are accepted.
 118          * @param $defaultNamespace Int the namespace to use if none is speci-
 119          *   fied by a prefix.  If you want to force a specific namespace even if
 120          *   $text might begin with a namespace prefix, use makeTitle() or
 121          *   makeTitleSafe().
 122          * @return Title, or null on an error.
 123          */
 124         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 125                 if ( is_object( $text ) ) {
 126                         throw new MWException( 'Title::newFromText given an object' );
 127                 }
 128
 129                 /**
 130                  * Wiki pages often contain multiple links to the same page.
 131                  * Title normalization and parsing can become expensive on
 132                  * pages with many links, so we can save a little time by
 133                  * caching them.
 134                  *
 135                  * In theory these are value objects and won't get changed...
 136                  */
 137                 if ( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 138                         return Title::$titleCache[$text];
 139                 }
 140
 141                 # Convert things like &eacute; &#257; or &#x3017; into normalized (bug 14952) text
 142                 $filteredText = Sanitizer::decodeCharReferencesAndNormalize( $text );
 143
 144                 $t = new Title();
 145                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 146                 $t->mDefaultNamespace = $defaultNamespace;
 147
 148                 static $cachedcount = 0 ;
 149                 if ( $t->secureAndSplit() ) {
 150                         if ( $defaultNamespace == NS_MAIN ) {
 151                                 if ( $cachedcount >= self::CACHE_MAX ) {
 152                                         # Avoid memory leaks on mass operations...
 153                                         Title::$titleCache = array();
 154                                         $cachedcount = 0;
 155                                 }
 156                                 $cachedcount++;
 157                                 Title::$titleCache[$text] =& $t;
 158                         }
 159                         return $t;
 160                 } else {
 161                         $ret = null;
 162                         return $ret;
 163                 }
 164         }
 165
 166         /**
 167          * THIS IS NOT THE FUNCTION YOU WANT. Use Title::newFromText().
 168          *
 169          * Example of wrong and broken code:
 170          * $title = Title::newFromURL( $wgRequest->getVal( 'title' ) );
 171          *
 172          * Example of right code:
 173          * $title = Title::newFromText( $wgRequest->getVal( 'title' ) );
 174          *
 175          * Create a new Title from URL-encoded text. Ensures that
 176          * the given title's length does not exceed the maximum.
 177          *
 178          * @param $url String the title, as might be taken from a URL
 179          * @return Title the new object, or NULL on an error
 180          */
 181         public static function newFromURL( $url ) {
 182                 global $wgLegalTitleChars;
 183                 $t = new Title();
 184
 185                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 186                 # but some URLs used it as a space replacement and they still come
 187                 # from some external search tools.
 188                 if ( strpos( $wgLegalTitleChars, '+' ) === false ) {
 189                         $url = str_replace( '+', ' ', $url );
 190                 }
 191
 192                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 193                 if ( $t->secureAndSplit() ) {
 194                         return $t;
 195                 } else {
 196                         return null;
 197                 }
 198         }
 199
 200         /**
 201          * Create a new Title from an article ID
 202          *
 203          * @param $id Int the page_id corresponding to the Title to create
 204          * @param $flags Int use Title::GAID_FOR_UPDATE to use master
 205          * @return Title the new object, or NULL on an error
 206          */
 207         public static function newFromID( $id, $flags = 0 ) {
 208                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
 209                 $row = $db->selectRow( 'page', '*', array( 'page_id' => $id ), __METHOD__ );
 210                 if ( $row !== false ) {
 211                         $title = Title::newFromRow( $row );
 212                 } else {
 213                         $title = null;
 214                 }
 215                 return $title;
 216         }
 217
 218         /**
 219          * Make an array of titles from an array of IDs
 220          *
 221          * @param $ids Array of Int Array of IDs
 222          * @return Array of Titles
 223          */
 224         public static function newFromIDs( $ids ) {
 225                 if ( !count( $ids ) ) {
 226                         return array();
 227                 }
 228                 $dbr = wfGetDB( DB_SLAVE );
 229
 230                 $res = $dbr->select(
 231                         'page',
 232                         array(
 233                                 'page_namespace', 'page_title', 'page_id',
 234                                 'page_len', 'page_is_redirect', 'page_latest',
 235                         ),
 236                         array( 'page_id' => $ids ),
 237                         __METHOD__
 238                 );
 239
 240                 $titles = array();
 241                 foreach ( $res as $row ) {
 242                         $titles[] = Title::newFromRow( $row );
 243                 }
 244                 return $titles;
 245         }
 246
 247         /**
 248          * Make a Title object from a DB row
 249          *
 250          * @param $row Object database row (needs at least page_title,page_namespace)
 251          * @return Title corresponding Title
 252          */
 253         public static function newFromRow( $row ) {
 254                 $t = self::makeTitle( $row->page_namespace, $row->page_title );
 255                 $t->loadFromRow( $row );
 256                 return $t;
 257         }
 258
 259         /**
 260          * Load Title object fields from a DB row.
 261          * If false is given, the title will be treated as non-existing.
 262          *
 263          * @param $row Object|false database row
 264          * @return void
 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; # FIXME: whene3ver page_latest is updated, also update page_content_model
 276             if ( isset( $row->page_content_model ) )
 277                 $this->mContentModelName = $row->page_content_model;
 278             else
 279                 $this->mContentModelName = null; # initialized lazily in getContentModelName()
 280                 } else { // page not found
 281                         $this->mArticleID = 0;
 282                         $this->mLength = 0;
 283                         $this->mRedirect = false;
 284                         $this->mLatestID = 0;
 285             $this->mContentModelName = null; # initialized lazily in getContentModelName()
 286                 }
 287         }
 288
 289         /**
 290          * Create a new Title from a namespace index and a DB key.
 291          * It's assumed that $ns and $title are *valid*, for instance when
 292          * they came directly from the database or a special page name.
 293          * For convenience, spaces are converted to underscores so that
 294          * eg user_text fields can be used directly.
 295          *
 296          * @param $ns Int the namespace of the article
 297          * @param $title String the unprefixed database key form
 298          * @param $fragment String the link fragment (after the "#")
 299          * @param $interwiki String the interwiki prefix
 300          * @return Title the new object
 301          */
 302         public static function &makeTitle( $ns, $title, $fragment = '', $interwiki = '' ) {
 303                 $t = new Title();
 304                 $t->mInterwiki = $interwiki;
 305                 $t->mFragment = $fragment;
 306                 $t->mNamespace = $ns = intval( $ns );
 307                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 308                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 309                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 310                 $t->mTextform = str_replace( '_', ' ', $title );
 311         $t->mContentModelName = null; # initialized lazily in getContentModelName()
 312                 return $t;
 313         }
 314
 315         /**
 316          * Create a new Title from a namespace index and a DB key.
 317          * The parameters will be checked for validity, which is a bit slower
 318          * than makeTitle() but safer for user-provided data.
 319          *
 320          * @param $ns Int the namespace of the article
 321          * @param $title String database key form
 322          * @param $fragment String the link fragment (after the "#")
 323          * @param $interwiki String interwiki prefix
 324          * @return Title the new object, or NULL on an error
 325          */
 326         public static function makeTitleSafe( $ns, $title, $fragment = '', $interwiki = '' ) {
 327                 $t = new Title();
 328                 $t->mDbkeyform = Title::makeName( $ns, $title, $fragment, $interwiki );
 329                 if ( $t->secureAndSplit() ) {
 330                         return $t;
 331                 } else {
 332                         return null;
 333                 }
 334         }
 335
 336         /**
 337          * Create a new Title for the Main Page
 338          *
 339          * @return Title the new object
 340          */
 341         public static function newMainPage() {
 342                 $title = Title::newFromText( wfMsgForContent( 'mainpage' ) );
 343                 // Don't give fatal errors if the message is broken
 344                 if ( !$title ) {
 345                         $title = Title::newFromText( 'Main Page' );
 346                 }
 347                 return $title;
 348         }
 349
 350         /**
 351          * Extract a redirect destination from a string and return the
 352          * Title, or null if the text doesn't contain a valid redirect
 353          * This will only return the very next target, useful for
 354          * the redirect table and other checks that don't need full recursion
 355          *
 356          * @param $text String: Text with possible redirect
 357          * @return Title: The corresponding Title
 358          */
 359         public static function newFromRedirect( $text ) {
 360                 return self::newFromRedirectInternal( $text );
 361         }
 362
 363         /**
 364          * Extract a redirect destination from a string and return the
 365          * Title, or null if the text doesn't contain a valid redirect
 366          * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
 367          * in order to provide (hopefully) the Title of the final destination instead of another redirect
 368          *
 369          * @param $text String Text with possible redirect
 370          * @return Title
 371          */
 372         public static function newFromRedirectRecurse( $text ) {
 373                 $titles = self::newFromRedirectArray( $text );
 374                 return $titles ? array_pop( $titles ) : null;
 375         }
 376
 377         /**
 378          * Extract a redirect destination from a string and return an
 379          * array of Titles, or null if the text doesn't contain a valid redirect
 380          * The last element in the array is the final destination after all redirects
 381          * have been resolved (up to $wgMaxRedirects times)
 382          *
 383          * @param $text String Text with possible redirect
 384          * @return Array of Titles, with the destination last
 385          */
 386         public static function newFromRedirectArray( $text ) {
 387                 global $wgMaxRedirects;
 388                 $title = self::newFromRedirectInternal( $text );
 389                 if ( is_null( $title ) ) {
 390                         return null;
 391                 }
 392                 // recursive check to follow double redirects
 393                 $recurse = $wgMaxRedirects;
 394                 $titles = array( $title );
 395                 while ( --$recurse > 0 ) {
 396                         if ( $title->isRedirect() ) {
 397                                 $page = WikiPage::factory( $title );
 398                                 $newtitle = $page->getRedirectTarget();
 399                         } else {
 400                                 break;
 401                         }
 402                         // Redirects to some special pages are not permitted
 403                         if ( $newtitle instanceOf Title && $newtitle->isValidRedirectTarget() ) {
 404                                 // the new title passes the checks, so make that our current title so that further recursion can be checked
 405                                 $title = $newtitle;
 406                                 $titles[] = $newtitle;
 407                         } else {
 408                                 break;
 409                         }
 410                 }
 411                 return $titles;
 412         }
 413
 414         /**
 415          * Really extract the redirect destination
 416          * Do not call this function directly, use one of the newFromRedirect* functions above
 417          *
 418          * @param $text String Text with possible redirect
 419          * @return Title
 420          */
 421         protected static function newFromRedirectInternal( $text ) {
 422                 global $wgMaxRedirects;
 423                 if ( $wgMaxRedirects < 1 ) {
 424                         //redirects are disabled, so quit early
 425                         return null;
 426                 }
 427                 $redir = MagicWord::get( 'redirect' );
 428                 $text = trim( $text );
 429                 if ( $redir->matchStartAndRemove( $text ) ) {
 430                         // Extract the first link and see if it's usable
 431                         // Ensure that it really does come directly after #REDIRECT
 432                         // Some older redirects included a colon, so don't freak about that!
 433                         $m = array();
 434                         if ( preg_match( '!^\s*:?\s*\[{2}(.*?)(?:\|.*?)?\]{2}!', $text, $m ) ) {
 435                                 // Strip preceding colon used to "escape" categories, etc.
 436                                 // and URL-decode links
 437                                 if ( strpos( $m[1], '%' ) !== false ) {
 438                                         // Match behavior of inline link parsing here;
 439                                         $m[1] = rawurldecode( ltrim( $m[1], ':' ) );
 440                                 }
 441                                 $title = Title::newFromText( $m[1] );
 442                                 // If the title is a redirect to bad special pages or is invalid, return null
 443                                 if ( !$title instanceof Title || !$title->isValidRedirectTarget() ) {
 444                                         return null;
 445                                 }
 446                                 return $title;
 447                         }
 448                 }
 449                 return null;
 450         }
 451
 452         /**
 453          * Get the prefixed DB key associated with an ID
 454          *
 455          * @param $id Int the page_id of the article
 456          * @return Title an object representing the article, or NULL if no such article was found
 457          */
 458         public static function nameOf( $id ) {
 459                 $dbr = wfGetDB( DB_SLAVE );
 460
 461                 $s = $dbr->selectRow(
 462                         'page',
 463                         array( 'page_namespace', 'page_title' ),
 464                         array( 'page_id' => $id ),
 465                         __METHOD__
 466                 );
 467                 if ( $s === false ) {
 468                         return null;
 469                 }
 470
 471                 $n = self::makeName( $s->page_namespace, $s->page_title );
 472                 return $n;
 473         }
 474
 475         /**
 476          * Get a regex character class describing the legal characters in a link
 477          *
 478          * @return String the list of characters, not delimited
 479          */
 480         public static function legalChars() {
 481                 global $wgLegalTitleChars;
 482                 return $wgLegalTitleChars;
 483         }
 484
 485         /**
 486          * Returns a simple regex that will match on characters and sequences invalid in titles.
 487          * Note that this doesn't pick up many things that could be wrong with titles, but that
 488          * replacing this regex with something valid will make many titles valid.
 489          *
 490          * @return String regex string
 491          */
 492         static function getTitleInvalidRegex() {
 493                 static $rxTc = false;
 494                 if ( !$rxTc ) {
 495                         # Matching titles will be held as illegal.
 496                         $rxTc = '/' .
 497                                 # Any character not allowed is forbidden...
 498                                 '[^' . self::legalChars() . ']' .
 499                                 # URL percent encoding sequences interfere with the ability
 500                                 # to round-trip titles -- you can't link to them consistently.
 501                                 '|%[0-9A-Fa-f]{2}' .
 502                                 # XML/HTML character references produce similar issues.
 503                                 '|&[A-Za-z0-9\x80-\xff]+;' .
 504                                 '|&#[0-9]+;' .
 505                                 '|&#x[0-9A-Fa-f]+;' .
 506                                 '/S';
 507                 }
 508
 509                 return $rxTc;
 510         }
 511
 512         /**
 513          * Get a string representation of a title suitable for
 514          * including in a search index
 515          *
 516          * @param $ns Int a namespace index
 517          * @param $title String text-form main part
 518          * @return String a stripped-down title string ready for the search index
 519          */
 520         public static function indexTitle( $ns, $title ) {
 521                 global $wgContLang;
 522
 523                 $lc = SearchEngine::legalSearchChars() . '&#;';
 524                 $t = $wgContLang->normalizeForSearch( $title );
 525                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 526                 $t = $wgContLang->lc( $t );
 527
 528                 # Handle 's, s'
 529                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 530                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 531
 532                 $t = preg_replace( "/\\s+/", ' ', $t );
 533
 534                 if ( $ns == NS_FILE ) {
 535                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 536                 }
 537                 return trim( $t );
 538         }
 539
 540         /**
 541          * Make a prefixed DB key from a DB key and a namespace index
 542          *
 543          * @param $ns Int numerical representation of the namespace
 544          * @param $title String the DB key form the title
 545          * @param $fragment String The link fragment (after the "#")
 546          * @param $interwiki String The interwiki prefix
 547          * @return String the prefixed form of the title
 548          */
 549         public static function makeName( $ns, $title, $fragment = '', $interwiki = '' ) {
 550                 global $wgContLang;
 551
 552                 $namespace = $wgContLang->getNsText( $ns );
 553                 $name = $namespace == '' ? $title : "$namespace:$title";
 554                 if ( strval( $interwiki ) != '' ) {
 555                         $name = "$interwiki:$name";
 556                 }
 557                 if ( strval( $fragment ) != '' ) {
 558                         $name .= '#' . $fragment;
 559                 }
 560                 return $name;
 561         }
 562
 563         /**
 564          * Escape a text fragment, say from a link, for a URL
 565          *
 566          * @param $fragment string containing a URL or link fragment (after the "#")
 567          * @return String: escaped string
 568          */
 569         static function escapeFragmentForURL( $fragment ) {
 570                 # Note that we don't urlencode the fragment.  urlencoded Unicode
 571                 # fragments appear not to work in IE (at least up to 7) or in at least
 572                 # one version of Opera 9.x.  The W3C validator, for one, doesn't seem
 573                 # to care if they aren't encoded.
 574                 return Sanitizer::escapeId( $fragment, 'noninitial' );
 575         }
 576
 577         /**
 578          * Callback for usort() to do title sorts by (namespace, title)
 579          *
 580          * @param $a Title
 581          * @param $b Title
 582          *
 583          * @return Integer: result of string comparison, or namespace comparison
 584          */
 585         public static function compare( $a, $b ) {
 586                 if ( $a->getNamespace() == $b->getNamespace() ) {
 587                         return strcmp( $a->getText(), $b->getText() );
 588                 } else {
 589                         return $a->getNamespace() - $b->getNamespace();
 590                 }
 591         }
 592
 593         /**
 594          * Determine whether the object refers to a page within
 595          * this project.
 596          *
 597          * @return Bool TRUE if this is an in-project interwiki link or a wikilink, FALSE otherwise
 598          */
 599         public function isLocal() {
 600                 if ( $this->mInterwiki != '' ) {
 601                         return Interwiki::fetch( $this->mInterwiki )->isLocal();
 602                 } else {
 603                         return true;
 604                 }
 605         }
 606
 607         /**
 608          * Is this Title interwiki?
 609          *
 610          * @return Bool
 611          */
 612         public function isExternal() {
 613                 return ( $this->mInterwiki != '' );
 614         }
 615
 616         /**
 617          * Get the interwiki prefix (or null string)
 618          *
 619          * @return String Interwiki prefix
 620          */
 621         public function getInterwiki() {
 622                 return $this->mInterwiki;
 623         }
 624
 625         /**
 626          * Determine whether the object refers to a page within
 627          * this project and is transcludable.
 628          *
 629          * @return Bool TRUE if this is transcludable
 630          */
 631         public function isTrans() {
 632                 if ( $this->mInterwiki == '' ) {
 633                         return false;
 634                 }
 635
 636                 return Interwiki::fetch( $this->mInterwiki )->isTranscludable();
 637         }
 638
 639         /**
 640          * Returns the DB name of the distant wiki which owns the object.
 641          *
 642          * @return String the DB name
 643          */
 644         public function getTransWikiID() {
 645                 if ( $this->mInterwiki == '' ) {
 646                         return false;
 647                 }
 648
 649                 return Interwiki::fetch( $this->mInterwiki )->getWikiID();
 650         }
 651
 652         /**
 653          * Get the text form (spaces not underscores) of the main part
 654          *
 655          * @return String Main part of the title
 656          */
 657         public function getText() {
 658                 return $this->mTextform;
 659         }
 660
 661         /**
 662          * Get the URL-encoded form of the main part
 663          *
 664          * @return String Main part of the title, URL-encoded
 665          */
 666         public function getPartialURL() {
 667                 return $this->mUrlform;
 668         }
 669
 670         /**
 671          * Get the main part with underscores
 672          *
 673          * @return String: Main part of the title, with underscores
 674          */
 675         public function getDBkey() {
 676                 return $this->mDbkeyform;
 677         }
 678
 679         /**
 680          * Get the DB key with the initial letter case as specified by the user
 681          *
 682          * @return String DB key
 683          */
 684         function getUserCaseDBKey() {
 685                 return $this->mUserCaseDBKey;
 686         }
 687
 688         /**
 689          * Get the namespace index, i.e. one of the NS_xxxx constants.
 690          *
 691          * @return Integer: Namespace index
 692          */
 693         public function getNamespace() {
 694                 return $this->mNamespace;
 695         }
 696
 697     /**
 698      * Get the page's content model name
 699      *
 700      * @return Integer: Namespace index
 701      */
 702     public function getContentModelName() {
 703         if ( empty( $this->mContentModelName ) ) {
 704             $this->mContentModelName = ContentHandler::getDefaultModelFor( $this );
 705         }
 706
 707         return $this->mContentModelName;
 708     }
 709
 710     /**
 711      * Conveniance method for checking a title's content model name
 712      *
 713      * @param $name
 714      * @return true if $this->getContentModelName() == $name
 715      */
 716     public function hasContentModel( $name ) {
 717         return $this->getContentModelName() == $name;
 718     }
 719
 720         /**
 721          * Get the namespace text
 722          *
 723          * @return String: Namespace text
 724          */
 725         public function getNsText() {
 726                 global $wgContLang;
 727
 728                 if ( $this->mInterwiki != '' ) {
 729                         // This probably shouldn't even happen. ohh man, oh yuck.
 730                         // But for interwiki transclusion it sometimes does.
 731                         // Shit. Shit shit shit.
 732                         //
 733                         // Use the canonical namespaces if possible to try to
 734                         // resolve a foreign namespace.
 735                         if ( MWNamespace::exists( $this->mNamespace ) ) {
 736                                 return MWNamespace::getCanonicalName( $this->mNamespace );
 737                         }
 738                 }
 739
 740                 // Strip off subpages
 741                 $pagename = $this->getText();
 742                 if ( strpos( $pagename, '/' ) !== false ) {
 743                         list( $username , ) = explode( '/', $pagename, 2 );
 744                 } else {
 745                         $username = $pagename;
 746                 }
 747
 748                 if ( $wgContLang->needsGenderDistinction() &&
 749                                 MWNamespace::hasGenderDistinction( $this->mNamespace ) ) {
 750                         $gender = GenderCache::singleton()->getGenderOf( $username, __METHOD__ );
 751                         return $wgContLang->getGenderNsText( $this->mNamespace, $gender );
 752                 }
 753
 754                 return $wgContLang->getNsText( $this->mNamespace );
 755         }
 756
 757         /**
 758          * Get the namespace text of the subject (rather than talk) page
 759          *
 760          * @return String Namespace text
 761          */
 762         public function getSubjectNsText() {
 763                 global $wgContLang;
 764                 return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
 765         }
 766
 767         /**
 768          * Get the namespace text of the talk page
 769          *
 770          * @return String Namespace text
 771          */
 772         public function getTalkNsText() {
 773                 global $wgContLang;
 774                 return( $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) ) );
 775         }
 776
 777         /**
 778          * Could this title have a corresponding talk page?
 779          *
 780          * @return Bool TRUE or FALSE
 781          */
 782         public function canTalk() {
 783                 return( MWNamespace::canTalk( $this->mNamespace ) );
 784         }
 785
 786         /**
 787          * Is this in a namespace that allows actual pages?
 788          *
 789          * @return Bool
 790          * @internal note -- uses hardcoded namespace index instead of constants
 791          */
 792         public function canExist() {
 793                 return $this->mNamespace >= NS_MAIN;
 794         }
 795
 796         /**
 797          * Can this title be added to a user's watchlist?
 798          *
 799          * @return Bool TRUE or FALSE
 800          */
 801         public function isWatchable() {
 802                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
 803         }
 804
 805         /**
 806          * Returns true if this is a special page.
 807          *
 808          * @return boolean
 809          */
 810         public function isSpecialPage() {
 811                 return $this->getNamespace() == NS_SPECIAL;
 812         }
 813
 814         /**
 815          * Returns true if this title resolves to the named special page
 816          *
 817          * @param $name String The special page name
 818          * @return boolean
 819          */
 820         public function isSpecial( $name ) {
 821                 if ( $this->isSpecialPage() ) {
 822                         list( $thisName, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $this->getDBkey() );
 823                         if ( $name == $thisName ) {
 824                                 return true;
 825                         }
 826                 }
 827                 return false;
 828         }
 829
 830         /**
 831          * If the Title refers to a special page alias which is not the local default, resolve
 832          * the alias, and localise the name as necessary.  Otherwise, return $this
 833          *
 834          * @return Title
 835          */
 836         public function fixSpecialName() {
 837                 if ( $this->isSpecialPage() ) {
 838                         list( $canonicalName, $par ) = SpecialPageFactory::resolveAlias( $this->mDbkeyform );
 839                         if ( $canonicalName ) {
 840                                 $localName = SpecialPageFactory::getLocalNameFor( $canonicalName, $par );
 841                                 if ( $localName != $this->mDbkeyform ) {
 842                                         return Title::makeTitle( NS_SPECIAL, $localName );
 843                                 }
 844                         }
 845                 }
 846                 return $this;
 847         }
 848
 849         /**
 850          * Returns true if the title is inside the specified namespace.
 851          *
 852          * Please make use of this instead of comparing to getNamespace()
 853          * This function is much more resistant to changes we may make
 854          * to namespaces than code that makes direct comparisons.
 855          * @param $ns int The namespace
 856          * @return bool
 857          * @since 1.19
 858          */
 859         public function inNamespace( $ns ) {
 860                 return MWNamespace::equals( $this->getNamespace(), $ns );
 861         }
 862
 863         /**
 864          * Returns true if the title is inside one of the specified namespaces.
 865          *
 866          * @param ...$namespaces The namespaces to check for
 867          * @return bool
 868          * @since 1.19
 869          */
 870         public function inNamespaces( /* ... */ ) {
 871                 $namespaces = func_get_args();
 872                 if ( count( $namespaces ) > 0 && is_array( $namespaces[0] ) ) {
 873                         $namespaces = $namespaces[0];
 874                 }
 875
 876                 foreach ( $namespaces as $ns ) {
 877                         if ( $this->inNamespace( $ns ) ) {
 878                                 return true;
 879                         }
 880                 }
 881
 882                 return false;
 883         }
 884
 885         /**
 886          * Returns true if the title has the same subject namespace as the
 887          * namespace specified.
 888          * For example this method will take NS_USER and return true if namespace
 889          * is either NS_USER or NS_USER_TALK since both of them have NS_USER
 890          * as their subject namespace.
 891          *
 892          * This is MUCH simpler than individually testing for equivilance
 893          * against both NS_USER and NS_USER_TALK, and is also forward compatible.
 894          * @since 1.19
 895          */
 896         public function hasSubjectNamespace( $ns ) {
 897                 return MWNamespace::subjectEquals( $this->getNamespace(), $ns );
 898         }
 899
 900         /**
 901          * Is this Title in a namespace which contains content?
 902          * In other words, is this a content page, for the purposes of calculating
 903          * statistics, etc?
 904          *
 905          * @return Boolean
 906          */
 907         public function isContentPage() {
 908                 return MWNamespace::isContent( $this->getNamespace() );
 909         }
 910
 911         /**
 912          * Would anybody with sufficient privileges be able to move this page?
 913          * Some pages just aren't movable.
 914          *
 915          * @return Bool TRUE or FALSE
 916          */
 917         public function isMovable() {
 918                 if ( !MWNamespace::isMovable( $this->getNamespace() ) || $this->getInterwiki() != '' ) {
 919                         // Interwiki title or immovable namespace. Hooks don't get to override here
 920                         return false;
 921                 }
 922
 923                 $result = true;
 924                 wfRunHooks( 'TitleIsMovable', array( $this, &$result ) );
 925                 return $result;
 926         }
 927
 928         /**
 929          * Is this the mainpage?
 930          * @note Title::newFromText seams to be sufficiently optimized by the title
 931          * cache that we don't need to over-optimize by doing direct comparisons and
 932          * acidentally creating new bugs where $title->equals( Title::newFromText() )
 933          * ends up reporting something differently than $title->isMainPage();
 934          *
 935          * @since 1.18
 936          * @return Bool
 937          */
 938         public function isMainPage() {
 939                 return $this->equals( Title::newMainPage() );
 940         }
 941
 942         /**
 943          * Is this a subpage?
 944          *
 945          * @return Bool
 946          */
 947         public function isSubpage() {
 948                 return MWNamespace::hasSubpages( $this->mNamespace )
 949                         ? strpos( $this->getText(), '/' ) !== false
 950                         : false;
 951         }
 952
 953         /**
 954          * Is this a conversion table for the LanguageConverter?
 955          *
 956          * @return Bool
 957          */
 958         public function isConversionTable() {
 959                 return $this->getNamespace() == NS_MEDIAWIKI &&
 960                         strpos( $this->getText(), 'Conversiontable' ) !== false;
 961         }
 962
 963         /**
 964          * Does that page contain wikitext, or it is JS, CSS or whatever?
 965          *
 966          * @return Bool
 967          */
 968         public function isWikitextPage() {
 969                 return $this->hasContentModel( CONTENT_MODEL_WIKITEXT );
 970         }
 971
 972         /**
 973          * Could this page contain custom CSS or JavaScript, based
 974          * on the title?
 975          *
 976          * @return Bool
 977          */
 978         public function isCssOrJsPage() {
 979                 return $this->hasContentModel( CONTENT_MODEL_CSS )
 980             || $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT );
 981         }
 982
 983         /**
 984          * Is this a .css or .js subpage of a user page?
 985          * @return Bool
 986          */
 987         public function isCssJsSubpage() {
 988                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
 989             && $this->isCssOrJsPage() );
 990         }
 991
 992         /**
 993          * Trim down a .css or .js subpage title to get the corresponding skin name
 994          *
 995          * @return string containing skin name from .css or .js subpage title
 996          */
 997         public function getSkinFromCssJsSubpage() {
 998                 $subpage = explode( '/', $this->mTextform );
 999                 $subpage = $subpage[ count( $subpage ) - 1 ];
1000                 $lastdot = strrpos( $subpage, '.' );
1001                 if ( $lastdot === false )
1002                         return $subpage; # Never happens: only called for names ending in '.css' or '.js'
1003                 return substr( $subpage, 0, $lastdot );
1004         }
1005
1006         /**
1007          * Is this a .css subpage of a user page?
1008          *
1009          * @return Bool
1010          */
1011         public function isCssSubpage() {
1012         return ( NS_USER == $this->mNamespace && $this->isSubpage()
1013             && $this->hasContentModel( CONTENT_MODEL_CSS ) );
1014         }
1015
1016         /**
1017          * Is this a .js subpage of a user page?
1018          *
1019          * @return Bool
1020          */
1021         public function isJsSubpage() {
1022         return ( NS_USER == $this->mNamespace && $this->isSubpage()
1023             && $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
1024         }
1025
1026         /**
1027          * Is this a talk page of some sort?
1028          *
1029          * @return Bool
1030          */
1031         public function isTalkPage() {
1032                 return MWNamespace::isTalk( $this->getNamespace() );
1033         }
1034
1035         /**
1036          * Get a Title object associated with the talk page of this article
1037          *
1038          * @return Title the object for the talk page
1039          */
1040         public function getTalkPage() {
1041                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1042         }
1043
1044         /**
1045          * Get a title object associated with the subject page of this
1046          * talk page
1047          *
1048          * @return Title the object for the subject page
1049          */
1050         public function getSubjectPage() {
1051                 // Is this the same title?
1052                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
1053                 if ( $this->getNamespace() == $subjectNS ) {
1054                         return $this;
1055                 }
1056                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
1057         }
1058
1059         /**
1060          * Get the default namespace index, for when there is no namespace
1061          *
1062          * @return Int Default namespace index
1063          */
1064         public function getDefaultNamespace() {
1065                 return $this->mDefaultNamespace;
1066         }
1067
1068         /**
1069          * Get title for search index
1070          *
1071          * @return String a stripped-down title string ready for the
1072          *  search index
1073          */
1074         public function getIndexTitle() {
1075                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
1076         }
1077
1078         /**
1079          * Get the Title fragment (i.e.\ the bit after the #) in text form
1080          *
1081          * @return String Title fragment
1082          */
1083         public function getFragment() {
1084                 return $this->mFragment;
1085         }
1086
1087         /**
1088          * Get the fragment in URL form, including the "#" character if there is one
1089          * @return String Fragment in URL form
1090          */
1091         public function getFragmentForURL() {
1092                 if ( $this->mFragment == '' ) {
1093                         return '';
1094                 } else {
1095                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
1096                 }
1097         }
1098
1099         /**
1100          * Set the fragment for this title. Removes the first character from the
1101          * specified fragment before setting, so it assumes you're passing it with
1102          * an initial "#".
1103          *
1104          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
1105          * Still in active use privately.
1106          *
1107          * @param $fragment String text
1108          */
1109         public function setFragment( $fragment ) {
1110                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
1111         }
1112
1113         /**
1114          * Prefix some arbitrary text with the namespace or interwiki prefix
1115          * of this object
1116          *
1117          * @param $name String the text
1118          * @return String the prefixed text
1119          * @private
1120          */
1121         private function prefix( $name ) {
1122                 $p = '';
1123                 if ( $this->mInterwiki != '' ) {
1124                         $p = $this->mInterwiki . ':';
1125                 }
1126
1127                 if ( 0 != $this->mNamespace ) {
1128                         $p .= $this->getNsText() . ':';
1129                 }
1130                 return $p . $name;
1131         }
1132
1133         /**
1134          * Get the prefixed database key form
1135          *
1136          * @return String the prefixed title, with underscores and
1137          *  any interwiki and namespace prefixes
1138          */
1139         public function getPrefixedDBkey() {
1140                 $s = $this->prefix( $this->mDbkeyform );
1141                 $s = str_replace( ' ', '_', $s );
1142                 return $s;
1143         }
1144
1145         /**
1146          * Get the prefixed title with spaces.
1147          * This is the form usually used for display
1148          *
1149          * @return String the prefixed title, with spaces
1150          */
1151         public function getPrefixedText() {
1152                 // @todo FIXME: Bad usage of empty() ?
1153                 if ( empty( $this->mPrefixedText ) ) {
1154                         $s = $this->prefix( $this->mTextform );
1155                         $s = str_replace( '_', ' ', $s );
1156                         $this->mPrefixedText = $s;
1157                 }
1158                 return $this->mPrefixedText;
1159         }
1160
1161         /**
1162          * Return a string representation of this title
1163          *
1164          * @return String representation of this title
1165          */
1166         public function __toString() {
1167                 return $this->getPrefixedText();
1168         }
1169
1170         /**
1171          * Get the prefixed title with spaces, plus any fragment
1172          * (part beginning with '#')
1173          *
1174          * @return String the prefixed title, with spaces and the fragment, including '#'
1175          */
1176         public function getFullText() {
1177                 $text = $this->getPrefixedText();
1178                 if ( $this->mFragment != '' ) {
1179                         $text .= '#' . $this->mFragment;
1180                 }
1181                 return $text;
1182         }
1183
1184         /**
1185          * Get the base page name, i.e. the leftmost part before any slashes
1186          *
1187          * @return String Base name
1188          */
1189         public function getBaseText() {
1190                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1191                         return $this->getText();
1192                 }
1193
1194                 $parts = explode( '/', $this->getText() );
1195                 # Don't discard the real title if there's no subpage involved
1196                 if ( count( $parts ) > 1 ) {
1197                         unset( $parts[count( $parts ) - 1] );
1198                 }
1199                 return implode( '/', $parts );
1200         }
1201
1202         /**
1203          * Get the lowest-level subpage name, i.e. the rightmost part after any slashes
1204          *
1205          * @return String Subpage name
1206          */
1207         public function getSubpageText() {
1208                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1209                         return( $this->mTextform );
1210                 }
1211                 $parts = explode( '/', $this->mTextform );
1212                 return( $parts[count( $parts ) - 1] );
1213         }
1214
1215         /**
1216          * Get the HTML-escaped displayable text form.
1217          * Used for the title field in <a> tags.
1218          *
1219          * @return String the text, including any prefixes
1220          */
1221         public function getEscapedText() {
1222                 wfDeprecated( __METHOD__, '1.19' );
1223                 return htmlspecialchars( $this->getPrefixedText() );
1224         }
1225
1226         /**
1227          * Get a URL-encoded form of the subpage text
1228          *
1229          * @return String URL-encoded subpage name
1230          */
1231         public function getSubpageUrlForm() {
1232                 $text = $this->getSubpageText();
1233                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
1234                 return( $text );
1235         }
1236
1237         /**
1238          * Get a URL-encoded title (not an actual URL) including interwiki
1239          *
1240          * @return String the URL-encoded form
1241          */
1242         public function getPrefixedURL() {
1243                 $s = $this->prefix( $this->mDbkeyform );
1244                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
1245                 return $s;
1246         }
1247
1248         /**
1249          * Helper to fix up the get{Local,Full,Link,Canonical}URL args
1250          * get{Canonical,Full,Link,Local}URL methods accepted an optional
1251          * second argument named variant. This was deprecated in favor
1252          * of passing an array of option with a "variant" key
1253          * Once $query2 is removed for good, this helper can be dropped
1254          * andthe wfArrayToCGI moved to getLocalURL();
1255          *
1256          * @since 1.19 (r105919)
1257          */
1258         private static function fixUrlQueryArgs( $query, $query2 = false ) {
1259                 if( $query2 !== false ) {
1260                         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" );
1261                 }
1262                 if ( is_array( $query ) ) {
1263                         $query = wfArrayToCGI( $query );
1264                 }
1265                 if ( $query2 ) {
1266                         if ( is_string( $query2 ) ) {
1267                                 // $query2 is a string, we will consider this to be
1268                                 // a deprecated $variant argument and add it to the query
1269                                 $query2 = wfArrayToCGI( array( 'variant' => $query2 ) );
1270                         } else {
1271                                 $query2 = wfArrayToCGI( $query2 );
1272                         }
1273                         // If we have $query content add a & to it first
1274                         if ( $query ) {
1275                                 $query .= '&';
1276                         }
1277                         // Now append the queries together
1278                         $query .= $query2;
1279                 }
1280                 return $query;
1281         }
1282
1283         /**
1284          * Get a real URL referring to this title, with interwiki link and
1285          * fragment
1286          *
1287          * See getLocalURL for the arguments.
1288          *
1289          * @see self::getLocalURL
1290          * @return String the URL
1291          */
1292         public function getFullURL( $query = '', $query2 = false ) {
1293                 $query = self::fixUrlQueryArgs( $query, $query2 );
1294
1295                 # Hand off all the decisions on urls to getLocalURL
1296                 $url = $this->getLocalURL( $query );
1297
1298                 # Expand the url to make it a full url. Note that getLocalURL has the
1299                 # potential to output full urls for a variety of reasons, so we use
1300                 # wfExpandUrl instead of simply prepending $wgServer
1301                 $url = wfExpandUrl( $url, PROTO_RELATIVE );
1302
1303                 # Finally, add the fragment.
1304                 $url .= $this->getFragmentForURL();
1305
1306                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
1307                 return $url;
1308         }
1309
1310         /**
1311          * Get a URL with no fragment or server name.  If this page is generated
1312          * with action=render, $wgServer is prepended.
1313          *
1314
1315          * @param $query \twotypes{\string,\array} an optional query string,
1316          *   not used for interwiki     links. Can be specified as an associative array as well,
1317          *   e.g., array( 'action' => 'edit' ) (keys and values will be URL-escaped).
1318          *   Some query patterns will trigger various shorturl path replacements.
1319          * @param $query2 Mixed: An optional secondary query array. This one MUST
1320          *   be an array. If a string is passed it will be interpreted as a deprecated
1321          *   variant argument and urlencoded into a variant= argument.
1322          *   This second query argument will be added to the $query
1323          *   The second parameter is deprecated since 1.19. Pass it as a key,value
1324          *   pair in the first parameter array instead.
1325          *
1326          * @return String the URL
1327          */
1328         public function getLocalURL( $query = '', $query2 = false ) {
1329                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
1330
1331                 $query = self::fixUrlQueryArgs( $query, $query2 );
1332
1333                 $interwiki = Interwiki::fetch( $this->mInterwiki );
1334                 if ( $interwiki ) {
1335                         $namespace = $this->getNsText();
1336                         if ( $namespace != '' ) {
1337                                 # Can this actually happen? Interwikis shouldn't be parsed.
1338                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
1339                                 $namespace .= ':';
1340                         }
1341                         $url = $interwiki->getURL( $namespace . $this->getDBkey() );
1342                         $url = wfAppendQuery( $url, $query );
1343                 } else {
1344                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
1345                         if ( $query == '' ) {
1346                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
1347                                 wfRunHooks( 'GetLocalURL::Article', array( &$this, &$url ) );
1348                         } else {
1349                                 global $wgVariantArticlePath, $wgActionPaths;
1350                                 $url = false;
1351                                 $matches = array();
1352
1353                                 if ( !empty( $wgActionPaths ) &&
1354                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
1355                                 {
1356                                         $action = urldecode( $matches[2] );
1357                                         if ( isset( $wgActionPaths[$action] ) ) {
1358                                                 $query = $matches[1];
1359                                                 if ( isset( $matches[4] ) ) {
1360                                                         $query .= $matches[4];
1361                                                 }
1362                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
1363                                                 if ( $query != '' ) {
1364                                                         $url = wfAppendQuery( $url, $query );
1365                                                 }
1366                                         }
1367                                 }
1368
1369                                 if ( $url === false &&
1370                                         $wgVariantArticlePath &&
1371                                         $this->getPageLanguage()->hasVariants() &&
1372                                         preg_match( '/^variant=([^&]*)$/', $query, $matches ) )
1373                                 {
1374                                         $variant = urldecode( $matches[1] );
1375                                         if ( $this->getPageLanguage()->hasVariant( $variant ) ) {
1376                                                 // Only do the variant replacement if the given variant is a valid
1377                                                 // variant for the page's language.
1378                                                 $url = str_replace( '$2', urlencode( $variant ), $wgVariantArticlePath );
1379                                                 $url = str_replace( '$1', $dbkey, $url );
1380                                         }
1381                                 }
1382
1383                                 if ( $url === false ) {
1384                                         if ( $query == '-' ) {
1385                                                 $query = '';
1386                                         }
1387                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
1388                                 }
1389                         }
1390
1391                         wfRunHooks( 'GetLocalURL::Internal', array( &$this, &$url, $query ) );
1392
1393                         // @todo FIXME: This causes breakage in various places when we
1394                         // actually expected a local URL and end up with dupe prefixes.
1395                         if ( $wgRequest->getVal( 'action' ) == 'render' ) {
1396                                 $url = $wgServer . $url;
1397                         }
1398                 }
1399                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
1400                 return $url;
1401         }
1402
1403         /**
1404          * Get a URL that's the simplest URL that will be valid to link, locally,
1405          * to the current Title.  It includes the fragment, but does not include
1406          * the server unless action=render is used (or the link is external).  If
1407          * there's a fragment but the prefixed text is empty, we just return a link
1408          * to the fragment.
1409          *
1410          * The result obviously should not be URL-escaped, but does need to be
1411          * HTML-escaped if it's being output in HTML.
1412          *
1413          * See getLocalURL for the arguments.
1414          *
1415          * @see self::getLocalURL
1416          * @return String the URL
1417          */
1418         public function getLinkURL( $query = '', $query2 = false ) {
1419                 wfProfileIn( __METHOD__ );
1420                 if ( $this->isExternal() ) {
1421                         $ret = $this->getFullURL( $query, $query2 );
1422                 } elseif ( $this->getPrefixedText() === '' && $this->getFragment() !== '' ) {
1423                         $ret = $this->getFragmentForURL();
1424                 } else {
1425                         $ret = $this->getLocalURL( $query, $query2 ) . $this->getFragmentForURL();
1426                 }
1427                 wfProfileOut( __METHOD__ );
1428                 return $ret;
1429         }
1430
1431         /**
1432          * Get an HTML-escaped version of the URL form, suitable for
1433          * using in a link, without a server name or fragment
1434          *
1435          * See getLocalURL for the arguments.
1436          *
1437          * @see self::getLocalURL
1438          * @return String the URL
1439          */
1440         public function escapeLocalURL( $query = '', $query2 = false ) {
1441                 wfDeprecated( __METHOD__, '1.19' );
1442                 return htmlspecialchars( $this->getLocalURL( $query, $query2 ) );
1443         }
1444
1445         /**
1446          * Get an HTML-escaped version of the URL form, suitable for
1447          * using in a link, including the server name and fragment
1448          *
1449          * See getLocalURL for the arguments.
1450          *
1451          * @see self::getLocalURL
1452          * @return String the URL
1453          */
1454         public function escapeFullURL( $query = '', $query2 = false ) {
1455                 wfDeprecated( __METHOD__, '1.19' );
1456                 return htmlspecialchars( $this->getFullURL( $query, $query2 ) );
1457         }
1458
1459         /**
1460          * Get the URL form for an internal link.
1461          * - Used in various Squid-related code, in case we have a different
1462          * internal hostname for the server from the exposed one.
1463          *
1464          * This uses $wgInternalServer to qualify the path, or $wgServer
1465          * if $wgInternalServer is not set. If the server variable used is
1466          * protocol-relative, the URL will be expanded to http://
1467          *
1468          * See getLocalURL for the arguments.
1469          *
1470          * @see self::getLocalURL
1471          * @return String the URL
1472          */
1473         public function getInternalURL( $query = '', $query2 = false ) {
1474                 global $wgInternalServer, $wgServer;
1475                 $query = self::fixUrlQueryArgs( $query, $query2 );
1476                 $server = $wgInternalServer !== false ? $wgInternalServer : $wgServer;
1477                 $url = wfExpandUrl( $server . $this->getLocalURL( $query ), PROTO_HTTP );
1478                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
1479                 return $url;
1480         }
1481
1482         /**
1483          * Get the URL for a canonical link, for use in things like IRC and
1484          * e-mail notifications. Uses $wgCanonicalServer and the
1485          * GetCanonicalURL hook.
1486          *
1487          * NOTE: Unlike getInternalURL(), the canonical URL includes the fragment
1488          *
1489          * See getLocalURL for the arguments.
1490          *
1491          * @see self::getLocalURL
1492          * @return string The URL
1493          * @since 1.18
1494          */
1495         public function getCanonicalURL( $query = '', $query2 = false ) {
1496                 $query = self::fixUrlQueryArgs( $query, $query2 );
1497                 $url = wfExpandUrl( $this->getLocalURL( $query ) . $this->getFragmentForURL(), PROTO_CANONICAL );
1498                 wfRunHooks( 'GetCanonicalURL', array( &$this, &$url, $query ) );
1499                 return $url;
1500         }
1501
1502         /**
1503          * HTML-escaped version of getCanonicalURL()
1504          *
1505          * See getLocalURL for the arguments.
1506          *
1507          * @see self::getLocalURL
1508          * @since 1.18
1509          */
1510         public function escapeCanonicalURL( $query = '', $query2 = false ) {
1511                 wfDeprecated( __METHOD__, '1.19' );
1512                 return htmlspecialchars( $this->getCanonicalURL( $query, $query2 ) );
1513         }
1514
1515         /**
1516          * Get the edit URL for this Title
1517          *
1518          * @return String the URL, or a null string if this is an
1519          *  interwiki link
1520          */
1521         public function getEditURL() {
1522                 if ( $this->mInterwiki != '' ) {
1523                         return '';
1524                 }
1525                 $s = $this->getLocalURL( 'action=edit' );
1526
1527                 return $s;
1528         }
1529
1530         /**
1531          * Is $wgUser watching this page?
1532          *
1533          * @return Bool
1534          */
1535         public function userIsWatching() {
1536                 global $wgUser;
1537
1538                 if ( is_null( $this->mWatched ) ) {
1539                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn() ) {
1540                                 $this->mWatched = false;
1541                         } else {
1542                                 $this->mWatched = $wgUser->isWatched( $this );
1543                         }
1544                 }
1545                 return $this->mWatched;
1546         }
1547
1548         /**
1549          * Can $wgUser read this page?
1550          *
1551          * @deprecated in 1.19; use userCan(), quickUserCan() or getUserPermissionsErrors() instead
1552          * @return Bool
1553          * @todo fold these checks into userCan()
1554          */
1555         public function userCanRead() {
1556                 wfDeprecated( __METHOD__, '1.19' );
1557                 return $this->userCan( 'read' );
1558         }
1559
1560         /**
1561          * Can $user perform $action on this page?
1562          * This skips potentially expensive cascading permission checks
1563          * as well as avoids expensive error formatting
1564          *
1565          * Suitable for use for nonessential UI controls in common cases, but
1566          * _not_ for functional access control.
1567          *
1568          * May provide false positives, but should never provide a false negative.
1569          *
1570          * @param $action String action that permission needs to be checked for
1571          * @param $user User to check (since 1.19); $wgUser will be used if not
1572          *              provided.
1573          * @return Bool
1574          */
1575         public function quickUserCan( $action, $user = null ) {
1576                 return $this->userCan( $action, $user, false );
1577         }
1578
1579         /**
1580          * Can $user perform $action on this page?
1581          *
1582          * @param $action String action that permission needs to be checked for
1583          * @param $user User to check (since 1.19); $wgUser will be used if not
1584          *   provided.
1585          * @param $doExpensiveQueries Bool Set this to false to avoid doing
1586          *   unnecessary queries.
1587          * @return Bool
1588          */
1589         public function userCan( $action, $user = null, $doExpensiveQueries = true ) {
1590                 if ( !$user instanceof User ) {
1591                         global $wgUser;
1592                         $user = $wgUser;
1593                 }
1594                 return !count( $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries, true ) );
1595         }
1596
1597         /**
1598          * Can $user perform $action on this page?
1599          *
1600          * @todo FIXME: This *does not* check throttles (User::pingLimiter()).
1601          *
1602          * @param $action String action that permission needs to be checked for
1603          * @param $user User to check
1604          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary
1605          *   queries by skipping checks for cascading protections and user blocks.
1606          * @param $ignoreErrors Array of Strings Set this to a list of message keys
1607          *   whose corresponding errors may be ignored.
1608          * @return Array of arguments to wfMsg to explain permissions problems.
1609          */
1610         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1611                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1612
1613                 // Remove the errors being ignored.
1614                 foreach ( $errors as $index => $error ) {
1615                         $error_key = is_array( $error ) ? $error[0] : $error;
1616
1617                         if ( in_array( $error_key, $ignoreErrors ) ) {
1618                                 unset( $errors[$index] );
1619                         }
1620                 }
1621
1622                 return $errors;
1623         }
1624
1625         /**
1626          * Permissions checks that fail most often, and which are easiest to test.
1627          *
1628          * @param $action String the action to check
1629          * @param $user User user to check
1630          * @param $errors Array list of current errors
1631          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1632          * @param $short Boolean short circuit on first error
1633          *
1634          * @return Array list of errors
1635          */
1636         private function checkQuickPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1637                 if ( $action == 'create' ) {
1638                         if ( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1639                                  ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1640                                 $errors[] = $user->isAnon() ? array( 'nocreatetext' ) : array( 'nocreate-loggedin' );
1641                         }
1642                 } elseif ( $action == 'move' ) {
1643                         if ( !$user->isAllowed( 'move-rootuserpages' )
1644                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1645                                 // Show user page-specific message only if the user can move other pages
1646                                 $errors[] = array( 'cant-move-user-page' );
1647                         }
1648
1649                         // Check if user is allowed to move files if it's a file
1650                         if ( $this->mNamespace == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1651                                 $errors[] = array( 'movenotallowedfile' );
1652                         }
1653
1654                         if ( !$user->isAllowed( 'move' ) ) {
1655                                 // User can't move anything
1656                                 global $wgGroupPermissions;
1657                                 $userCanMove = false;
1658                                 if ( isset( $wgGroupPermissions['user']['move'] ) ) {
1659                                         $userCanMove = $wgGroupPermissions['user']['move'];
1660                                 }
1661                                 $autoconfirmedCanMove = false;
1662                                 if ( isset( $wgGroupPermissions['autoconfirmed']['move'] ) ) {
1663                                         $autoconfirmedCanMove = $wgGroupPermissions['autoconfirmed']['move'];
1664                                 }
1665                                 if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
1666                                         // custom message if logged-in users without any special rights can move
1667                                         $errors[] = array( 'movenologintext' );
1668                                 } else {
1669                                         $errors[] = array( 'movenotallowed' );
1670                                 }
1671                         }
1672                 } elseif ( $action == 'move-target' ) {
1673                         if ( !$user->isAllowed( 'move' ) ) {
1674                                 // User can't move anything
1675                                 $errors[] = array( 'movenotallowed' );
1676                         } elseif ( !$user->isAllowed( 'move-rootuserpages' )
1677                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1678                                 // Show user page-specific message only if the user can move other pages
1679                                 $errors[] = array( 'cant-move-to-user-page' );
1680                         }
1681                 } elseif ( !$user->isAllowed( $action ) ) {
1682                         $errors[] = $this->missingPermissionError( $action, $short );
1683                 }
1684
1685                 return $errors;
1686         }
1687
1688         /**
1689          * Add the resulting error code to the errors array
1690          *
1691          * @param $errors Array list of current errors
1692          * @param $result Mixed result of errors
1693          *
1694          * @return Array list of errors
1695          */
1696         private function resultToError( $errors, $result ) {
1697                 if ( is_array( $result ) && count( $result ) && !is_array( $result[0] ) ) {
1698                         // A single array representing an error
1699                         $errors[] = $result;
1700                 } elseif ( is_array( $result ) && is_array( $result[0] ) ) {
1701                         // A nested array representing multiple errors
1702                         $errors = array_merge( $errors, $result );
1703                 } elseif ( $result !== '' && is_string( $result ) ) {
1704                         // A string representing a message-id
1705                         $errors[] = array( $result );
1706                 } elseif ( $result === false ) {
1707                         // a generic "We don't want them to do that"
1708                         $errors[] = array( 'badaccess-group0' );
1709                 }
1710                 return $errors;
1711         }
1712
1713         /**
1714          * Check various permission hooks
1715          *
1716          * @param $action String the action to check
1717          * @param $user User user to check
1718          * @param $errors Array list of current errors
1719          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1720          * @param $short Boolean short circuit on first error
1721          *
1722          * @return Array list of errors
1723          */
1724         private function checkPermissionHooks( $action, $user, $errors, $doExpensiveQueries, $short ) {
1725                 // Use getUserPermissionsErrors instead
1726                 $result = '';
1727                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1728                         return $result ? array() : array( array( 'badaccess-group0' ) );
1729                 }
1730                 // Check getUserPermissionsErrors hook
1731                 if ( !wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1732                         $errors = $this->resultToError( $errors, $result );
1733                 }
1734                 // Check getUserPermissionsErrorsExpensive hook
1735                 if ( $doExpensiveQueries && !( $short && count( $errors ) > 0 ) &&
1736                          !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) ) ) {
1737                         $errors = $this->resultToError( $errors, $result );
1738                 }
1739
1740                 return $errors;
1741         }
1742
1743         /**
1744          * Check permissions on special pages & namespaces
1745          *
1746          * @param $action String the action to check
1747          * @param $user User user to check
1748          * @param $errors Array list of current errors
1749          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1750          * @param $short Boolean short circuit on first error
1751          *
1752          * @return Array list of errors
1753          */
1754         private function checkSpecialsAndNSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1755                 # Only 'createaccount' and 'execute' can be performed on
1756                 # special pages, which don't actually exist in the DB.
1757                 $specialOKActions = array( 'createaccount', 'execute', 'read' );
1758                 if ( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions ) ) {
1759                         $errors[] = array( 'ns-specialprotected' );
1760                 }
1761
1762                 # Check $wgNamespaceProtection for restricted namespaces
1763                 if ( $this->isNamespaceProtected( $user ) ) {
1764                         $ns = $this->mNamespace == NS_MAIN ?
1765                                 wfMsg( 'nstab-main' ) : $this->getNsText();
1766                         $errors[] = $this->mNamespace == NS_MEDIAWIKI ?
1767                                 array( 'protectedinterface' ) : array( 'namespaceprotected',  $ns );
1768                 }
1769
1770                 return $errors;
1771         }
1772
1773         /**
1774          * Check CSS/JS sub-page permissions
1775          *
1776          * @param $action String the action to check
1777          * @param $user User user to check
1778          * @param $errors Array list of current errors
1779          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1780          * @param $short Boolean short circuit on first error
1781          *
1782          * @return Array list of errors
1783          */
1784         private function checkCSSandJSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1785                 # Protect css/js subpages of user pages
1786                 # XXX: this might be better using restrictions
1787                 # XXX: right 'editusercssjs' is deprecated, for backward compatibility only
1788                 if ( $action != 'patrol' && !$user->isAllowed( 'editusercssjs' )
1789                                 && !preg_match( '/^' . preg_quote( $user->getName(), '/' ) . '\//', $this->mTextform ) ) {
1790                         if ( $this->isCssSubpage() && !$user->isAllowed( 'editusercss' ) ) {
1791                                 $errors[] = array( 'customcssprotected' );
1792                         } elseif ( $this->isJsSubpage() && !$user->isAllowed( 'edituserjs' ) ) {
1793                                 $errors[] = array( 'customjsprotected' );
1794                         }
1795                 }
1796
1797                 return $errors;
1798         }
1799
1800         /**
1801          * Check against page_restrictions table requirements on this
1802          * page. The user must possess all required rights for this
1803          * action.
1804          *
1805          * @param $action String the action to check
1806          * @param $user User user to check
1807          * @param $errors Array list of current errors
1808          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1809          * @param $short Boolean short circuit on first error
1810          *
1811          * @return Array list of errors
1812          */
1813         private function checkPageRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1814                 foreach ( $this->getRestrictions( $action ) as $right ) {
1815                         // Backwards compatibility, rewrite sysop -> protect
1816                         if ( $right == 'sysop' ) {
1817                                 $right = 'protect';
1818                         }
1819                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1820                                 // Users with 'editprotected' permission can edit protected pages
1821                                 // without cascading option turned on.
1822                                 if ( $action != 'edit' || !$user->isAllowed( 'editprotected' )
1823                                         || $this->mCascadeRestriction )
1824                                 {
1825                                         $errors[] = array( 'protectedpagetext', $right );
1826                                 }
1827                         }
1828                 }
1829
1830                 return $errors;
1831         }
1832
1833         /**
1834          * Check restrictions on cascading pages.
1835          *
1836          * @param $action String the action to check
1837          * @param $user User to check
1838          * @param $errors Array list of current errors
1839          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1840          * @param $short Boolean short circuit on first error
1841          *
1842          * @return Array list of errors
1843          */
1844         private function checkCascadingSourcesRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1845                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1846                         # We /could/ use the protection level on the source page, but it's
1847                         # fairly ugly as we have to establish a precedence hierarchy for pages
1848                         # included by multiple cascade-protected pages. So just restrict
1849                         # it to people with 'protect' permission, as they could remove the
1850                         # protection anyway.
1851                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1852                         # Cascading protection depends on more than this page...
1853                         # Several cascading protected pages may include this page...
1854                         # Check each cascading level
1855                         # This is only for protection restrictions, not for all actions
1856                         if ( isset( $restrictions[$action] ) ) {
1857                                 foreach ( $restrictions[$action] as $right ) {
1858                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1859                                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1860                                                 $pages = '';
1861                                                 foreach ( $cascadingSources as $page )
1862                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1863                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1864                                         }
1865                                 }
1866                         }
1867                 }
1868
1869                 return $errors;
1870         }
1871
1872         /**
1873          * Check action permissions not already checked in checkQuickPermissions
1874          *
1875          * @param $action String the action to check
1876          * @param $user User to check
1877          * @param $errors Array list of current errors
1878          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1879          * @param $short Boolean short circuit on first error
1880          *
1881          * @return Array list of errors
1882          */
1883         private function checkActionPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1884                 global $wgDeleteRevisionsLimit, $wgLang;
1885
1886                 if ( $action == 'protect' ) {
1887                         if ( count( $this->getUserPermissionsErrorsInternal( 'edit', $user, $doExpensiveQueries, true ) ) ) {
1888                                 // If they can't edit, they shouldn't protect.
1889                                 $errors[] = array( 'protect-cantedit' );
1890                         }
1891                 } elseif ( $action == 'create' ) {
1892                         $title_protection = $this->getTitleProtection();
1893                         if( $title_protection ) {
1894                                 if( $title_protection['pt_create_perm'] == 'sysop' ) {
1895                                         $title_protection['pt_create_perm'] = 'protect'; // B/C
1896                                 }
1897                                 if( $title_protection['pt_create_perm'] == '' ||
1898                                         !$user->isAllowed( $title_protection['pt_create_perm'] ) )
1899                                 {
1900                                         $errors[] = array( 'titleprotected', User::whoIs( $title_protection['pt_user'] ), $title_protection['pt_reason'] );
1901                                 }
1902                         }
1903                 } elseif ( $action == 'move' ) {
1904                         // Check for immobile pages
1905                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1906                                 // Specific message for this case
1907                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1908                         } elseif ( !$this->isMovable() ) {
1909                                 // Less specific message for rarer cases
1910                                 $errors[] = array( 'immobile-source-page' );
1911                         }
1912                 } elseif ( $action == 'move-target' ) {
1913                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1914                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1915                         } elseif ( !$this->isMovable() ) {
1916                                 $errors[] = array( 'immobile-target-page' );
1917                         }
1918                 } elseif ( $action == 'delete' ) {
1919                         if ( $doExpensiveQueries && $wgDeleteRevisionsLimit
1920                                 && !$this->userCan( 'bigdelete', $user ) && $this->isBigDeletion() )
1921                         {
1922                                 $errors[] = array( 'delete-toobig', $wgLang->formatNum( $wgDeleteRevisionsLimit ) );
1923                         }
1924                 }
1925                 return $errors;
1926         }
1927
1928         /**
1929          * Check that the user isn't blocked from editting.
1930          *
1931          * @param $action String the action to check
1932          * @param $user User to check
1933          * @param $errors Array list of current errors
1934          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1935          * @param $short Boolean short circuit on first error
1936          *
1937          * @return Array list of errors
1938          */
1939         private function checkUserBlock( $action, $user, $errors, $doExpensiveQueries, $short ) {
1940                 // Account creation blocks handled at userlogin.
1941                 // Unblocking handled in SpecialUnblock
1942                 if( !$doExpensiveQueries || in_array( $action, array( 'createaccount', 'unblock' ) ) ) {
1943                         return $errors;
1944                 }
1945
1946                 global $wgContLang, $wgLang, $wgEmailConfirmToEdit;
1947
1948                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() ) {
1949                         $errors[] = array( 'confirmedittext' );
1950                 }
1951
1952                 if ( ( $action == 'edit' || $action == 'create' ) && !$user->isBlockedFrom( $this ) ) {
1953                         // Don't block the user from editing their own talk page unless they've been
1954                         // explicitly blocked from that too.
1955                 } elseif( $user->isBlocked() && $user->mBlock->prevents( $action ) !== false ) {
1956                         $block = $user->mBlock;
1957
1958                         // This is from OutputPage::blockedPage
1959                         // Copied at r23888 by werdna
1960
1961                         $id = $user->blockedBy();
1962                         $reason = $user->blockedFor();
1963                         if ( $reason == '' ) {
1964                                 $reason = wfMsg( 'blockednoreason' );
1965                         }
1966                         $ip = $user->getRequest()->getIP();
1967
1968                         if ( is_numeric( $id ) ) {
1969                                 $name = User::whoIs( $id );
1970                         } else {
1971                                 $name = $id;
1972                         }
1973
1974                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1975                         $blockid = $block->getId();
1976                         $blockExpiry = $user->mBlock->mExpiry;
1977                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $user->mBlock->mTimestamp ), true );
1978                         if ( $blockExpiry == 'infinity' ) {
1979                                 $blockExpiry = wfMessage( 'infiniteblock' )->text();
1980                         } else {
1981                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1982                         }
1983
1984                         $intended = strval( $user->mBlock->getTarget() );
1985
1986                         $errors[] = array( ( $block->mAuto ? 'autoblockedtext' : 'blockedtext' ), $link, $reason, $ip, $name,
1987                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
1988                 }
1989
1990                 return $errors;
1991         }
1992
1993         /**
1994          * Check that the user is allowed to read this page.
1995          *
1996          * @param $action String the action to check
1997          * @param $user User to check
1998          * @param $errors Array list of current errors
1999          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
2000          * @param $short Boolean short circuit on first error
2001          *
2002          * @return Array list of errors
2003          */
2004         private function checkReadPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
2005                 global $wgWhitelistRead, $wgGroupPermissions, $wgRevokePermissions;
2006                 static $useShortcut = null;
2007
2008                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
2009                 if ( is_null( $useShortcut ) ) {
2010                         $useShortcut = true;
2011                         if ( empty( $wgGroupPermissions['*']['read'] ) ) {
2012                                 # Not a public wiki, so no shortcut
2013                                 $useShortcut = false;
2014                         } elseif ( !empty( $wgRevokePermissions ) ) {
2015                                 /**
2016                                  * Iterate through each group with permissions being revoked (key not included since we don't care
2017                                  * what the group name is), then check if the read permission is being revoked. If it is, then
2018                                  * we don't use the shortcut below since the user might not be able to read, even though anon
2019                                  * reading is allowed.
2020                                  */
2021                                 foreach ( $wgRevokePermissions as $perms ) {
2022                                         if ( !empty( $perms['read'] ) ) {
2023                                                 # We might be removing the read right from the user, so no shortcut
2024                                                 $useShortcut = false;
2025                                                 break;
2026                                         }
2027                                 }
2028                         }
2029                 }
2030
2031                 $whitelisted = false;
2032                 if ( $useShortcut ) {
2033                         # Shortcut for public wikis, allows skipping quite a bit of code
2034                         $whitelisted = true;
2035                 } elseif ( $user->isAllowed( 'read' ) ) {
2036                         # If the user is allowed to read pages, he is allowed to read all pages
2037                         $whitelisted = true;
2038                 } elseif ( $this->isSpecial( 'Userlogin' )
2039                         || $this->isSpecial( 'ChangePassword' )
2040                         || $this->isSpecial( 'PasswordReset' )
2041                 ) {
2042                         # Always grant access to the login page.
2043                         # Even anons need to be able to log in.
2044                         $whitelisted = true;
2045                 } elseif ( is_array( $wgWhitelistRead ) && count( $wgWhitelistRead ) ) {
2046                         # Time to check the whitelist
2047                         # Only do these checks is there's something to check against
2048                         $name = $this->getPrefixedText();
2049                         $dbName = $this->getPrefixedDBKey();
2050
2051                         // Check with and without underscores
2052                         if ( in_array( $name, $wgWhitelistRead, true ) || in_array( $dbName, $wgWhitelistRead, true ) ) {
2053                                 # Check for explicit whitelisting
2054                                 $whitelisted = true;
2055                         } elseif ( $this->getNamespace() == NS_MAIN ) {
2056                                 # Old settings might have the title prefixed with
2057                                 # a colon for main-namespace pages
2058                                 if ( in_array( ':' . $name, $wgWhitelistRead ) ) {
2059                                         $whitelisted = true;
2060                                 }
2061                         } elseif ( $this->isSpecialPage() ) {
2062                                 # If it's a special page, ditch the subpage bit and check again
2063                                 $name = $this->getDBkey();
2064                                 list( $name, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $name );
2065                                 if ( $name !== false ) {
2066                                         $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
2067                                         if ( in_array( $pure, $wgWhitelistRead, true ) ) {
2068                                                 $whitelisted = true;
2069                                         }
2070                                 }
2071                         }
2072                 }
2073
2074                 if ( !$whitelisted ) {
2075                         # If the title is not whitelisted, give extensions a chance to do so...
2076                         wfRunHooks( 'TitleReadWhitelist', array( $this, $user, &$whitelisted ) );
2077                         if ( !$whitelisted ) {
2078                                 $errors[] = $this->missingPermissionError( $action, $short );
2079                         }
2080                 }
2081
2082                 return $errors;
2083         }
2084
2085         /**
2086          * Get a description array when the user doesn't have the right to perform
2087          * $action (i.e. when User::isAllowed() returns false)
2088          *
2089          * @param $action String the action to check
2090          * @param $short Boolean short circuit on first error
2091          * @return Array list of errors
2092          */
2093         private function missingPermissionError( $action, $short ) {
2094                 // We avoid expensive display logic for quickUserCan's and such
2095                 if ( $short ) {
2096                         return array( 'badaccess-group0' );
2097                 }
2098
2099                 $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
2100                         User::getGroupsWithPermission( $action ) );
2101
2102                 if ( count( $groups ) ) {
2103                         global $wgLang;
2104                         return array(
2105                                 'badaccess-groups',
2106                                 $wgLang->commaList( $groups ),
2107                                 count( $groups )
2108                         );
2109                 } else {
2110                         return array( 'badaccess-group0' );
2111                 }
2112         }
2113
2114         /**
2115          * Can $user perform $action on this page? This is an internal function,
2116          * which checks ONLY that previously checked by userCan (i.e. it leaves out
2117          * checks on wfReadOnly() and blocks)
2118          *
2119          * @param $action String action that permission needs to be checked for
2120          * @param $user User to check
2121          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary queries.
2122          * @param $short Bool Set this to true to stop after the first permission error.
2123          * @return Array of arrays of the arguments to wfMsg to explain permissions problems.
2124          */
2125         protected function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true, $short = false ) {
2126                 wfProfileIn( __METHOD__ );
2127
2128                 # Read has special handling
2129                 if ( $action == 'read' ) {
2130                         $checks = array(
2131                                 'checkPermissionHooks',
2132                                 'checkReadPermissions',
2133                         );
2134                 } else {
2135                         $checks = array(
2136                                 'checkQuickPermissions',
2137                                 'checkPermissionHooks',
2138                                 'checkSpecialsAndNSPermissions',
2139                                 'checkCSSandJSPermissions',
2140                                 'checkPageRestrictions',
2141                                 'checkCascadingSourcesRestrictions',
2142                                 'checkActionPermissions',
2143                                 'checkUserBlock'
2144                         );
2145                 }
2146
2147                 $errors = array();
2148                 while( count( $checks ) > 0 &&
2149                                 !( $short && count( $errors ) > 0 ) ) {
2150                         $method = array_shift( $checks );
2151                         $errors = $this->$method( $action, $user, $errors, $doExpensiveQueries, $short );
2152                 }
2153
2154                 wfProfileOut( __METHOD__ );
2155                 return $errors;
2156         }
2157
2158         /**
2159          * Protect css subpages of user pages: can $wgUser edit
2160          * this page?
2161          *
2162          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2163          * @return Bool
2164          */
2165         public function userCanEditCssSubpage() {
2166                 global $wgUser;
2167                 wfDeprecated( __METHOD__, '1.19' );
2168                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'editusercss' ) )
2169                         || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2170         }
2171
2172         /**
2173          * Protect js subpages of user pages: can $wgUser edit
2174          * this page?
2175          *
2176          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2177          * @return Bool
2178          */
2179         public function userCanEditJsSubpage() {
2180                 global $wgUser;
2181                 wfDeprecated( __METHOD__, '1.19' );
2182                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'edituserjs' ) )
2183                            || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2184         }
2185
2186         /**
2187          * Get a filtered list of all restriction types supported by this wiki.
2188          * @param bool $exists True to get all restriction types that apply to
2189          * titles that do exist, False for all restriction types that apply to
2190          * titles that do not exist
2191          * @return array
2192          */
2193         public static function getFilteredRestrictionTypes( $exists = true ) {
2194                 global $wgRestrictionTypes;
2195                 $types = $wgRestrictionTypes;
2196                 if ( $exists ) {
2197                         # Remove the create restriction for existing titles
2198                         $types = array_diff( $types, array( 'create' ) );
2199                 } else {
2200                         # Only the create and upload restrictions apply to non-existing titles
2201                         $types = array_intersect( $types, array( 'create', 'upload' ) );
2202                 }
2203                 return $types;
2204         }
2205
2206         /**
2207          * Returns restriction types for the current Title
2208          *
2209          * @return array applicable restriction types
2210          */
2211         public function getRestrictionTypes() {
2212                 if ( $this->isSpecialPage() ) {
2213                         return array();
2214                 }
2215
2216                 $types = self::getFilteredRestrictionTypes( $this->exists() );
2217
2218                 if ( $this->getNamespace() != NS_FILE ) {
2219                         # Remove the upload restriction for non-file titles
2220                         $types = array_diff( $types, array( 'upload' ) );
2221                 }
2222
2223                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
2224
2225                 wfDebug( __METHOD__ . ': applicable restrictions to [[' .
2226                         $this->getPrefixedText() . ']] are {' . implode( ',', $types ) . "}\n" );
2227
2228                 return $types;
2229         }
2230
2231         /**
2232          * Is this title subject to title protection?
2233          * Title protection is the one applied against creation of such title.
2234          *
2235          * @return Mixed An associative array representing any existent title
2236          *   protection, or false if there's none.
2237          */
2238         private function getTitleProtection() {
2239                 // Can't protect pages in special namespaces
2240                 if ( $this->getNamespace() < 0 ) {
2241                         return false;
2242                 }
2243
2244                 // Can't protect pages that exist.
2245                 if ( $this->exists() ) {
2246                         return false;
2247                 }
2248
2249                 if ( !isset( $this->mTitleProtection ) ) {
2250                         $dbr = wfGetDB( DB_SLAVE );
2251                         $res = $dbr->select( 'protected_titles', '*',
2252                                 array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2253                                 __METHOD__ );
2254
2255                         // fetchRow returns false if there are no rows.
2256                         $this->mTitleProtection = $dbr->fetchRow( $res );
2257                 }
2258                 return $this->mTitleProtection;
2259         }
2260
2261         /**
2262          * Update the title protection status
2263          *
2264          * @deprecated in 1.19; will be removed in 1.20. Use WikiPage::doUpdateRestrictions() instead.
2265          * @param $create_perm String Permission required for creation
2266          * @param $reason String Reason for protection
2267          * @param $expiry String Expiry timestamp
2268          * @return boolean true
2269          */
2270         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
2271                 wfDeprecated( __METHOD__, '1.19' );
2272
2273                 global $wgUser;
2274
2275                 $limit = array( 'create' => $create_perm );
2276                 $expiry = array( 'create' => $expiry );
2277
2278                 $page = WikiPage::factory( $this );
2279                 $status = $page->doUpdateRestrictions( $limit, $expiry, false, $reason, $wgUser );
2280
2281                 return $status->isOK();
2282         }
2283
2284         /**
2285          * Remove any title protection due to page existing
2286          */
2287         public function deleteTitleProtection() {
2288                 $dbw = wfGetDB( DB_MASTER );
2289
2290                 $dbw->delete(
2291                         'protected_titles',
2292                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2293                         __METHOD__
2294                 );
2295                 $this->mTitleProtection = false;
2296         }
2297
2298         /**
2299          * Is this page "semi-protected" - the *only* protection is autoconfirm?
2300          *
2301          * @param $action String Action to check (default: edit)
2302          * @return Bool
2303          */
2304         public function isSemiProtected( $action = 'edit' ) {
2305                 if ( $this->exists() ) {
2306                         $restrictions = $this->getRestrictions( $action );
2307                         if ( count( $restrictions ) > 0 ) {
2308                                 foreach ( $restrictions as $restriction ) {
2309                                         if ( strtolower( $restriction ) != 'autoconfirmed' ) {
2310                                                 return false;
2311                                         }
2312                                 }
2313                         } else {
2314                                 # Not protected
2315                                 return false;
2316                         }
2317                         return true;
2318                 } else {
2319                         # If it doesn't exist, it can't be protected
2320                         return false;
2321                 }
2322         }
2323
2324         /**
2325          * Does the title correspond to a protected article?
2326          *
2327          * @param $action String the action the page is protected from,
2328          * by default checks all actions.
2329          * @return Bool
2330          */
2331         public function isProtected( $action = '' ) {
2332                 global $wgRestrictionLevels;
2333
2334                 $restrictionTypes = $this->getRestrictionTypes();
2335
2336                 # Special pages have inherent protection
2337                 if( $this->isSpecialPage() ) {
2338                         return true;
2339                 }
2340
2341                 # Check regular protection levels
2342                 foreach ( $restrictionTypes as $type ) {
2343                         if ( $action == $type || $action == '' ) {
2344                                 $r = $this->getRestrictions( $type );
2345                                 foreach ( $wgRestrictionLevels as $level ) {
2346                                         if ( in_array( $level, $r ) && $level != '' ) {
2347                                                 return true;
2348                                         }
2349                                 }
2350                         }
2351                 }
2352
2353                 return false;
2354         }
2355
2356         /**
2357          * Determines if $user is unable to edit this page because it has been protected
2358          * by $wgNamespaceProtection.
2359          *
2360          * @param $user User object to check permissions
2361          * @return Bool
2362          */
2363         public function isNamespaceProtected( User $user ) {
2364                 global $wgNamespaceProtection;
2365
2366                 if ( isset( $wgNamespaceProtection[$this->mNamespace] ) ) {
2367                         foreach ( (array)$wgNamespaceProtection[$this->mNamespace] as $right ) {
2368                                 if ( $right != '' && !$user->isAllowed( $right ) ) {
2369                                         return true;
2370                                 }
2371                         }
2372                 }
2373                 return false;
2374         }
2375
2376         /**
2377          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
2378          *
2379          * @return Bool If the page is subject to cascading restrictions.
2380          */
2381         public function isCascadeProtected() {
2382                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
2383                 return ( $sources > 0 );
2384         }
2385
2386         /**
2387          * Cascading protection: Get the source of any cascading restrictions on this page.
2388          *
2389          * @param $getPages Bool Whether or not to retrieve the actual pages
2390          *        that the restrictions have come from.
2391          * @return Mixed Array of Title objects of the pages from which cascading restrictions
2392          *     have come, false for none, or true if such restrictions exist, but $getPages
2393          *     was not set.  The restriction array is an array of each type, each of which
2394          *     contains a array of unique groups.
2395          */
2396         public function getCascadeProtectionSources( $getPages = true ) {
2397                 global $wgContLang;
2398                 $pagerestrictions = array();
2399
2400                 if ( isset( $this->mCascadeSources ) && $getPages ) {
2401                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
2402                 } elseif ( isset( $this->mHasCascadingRestrictions ) && !$getPages ) {
2403                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
2404                 }
2405
2406                 wfProfileIn( __METHOD__ );
2407
2408                 $dbr = wfGetDB( DB_SLAVE );
2409
2410                 if ( $this->getNamespace() == NS_FILE ) {
2411                         $tables = array( 'imagelinks', 'page_restrictions' );
2412                         $where_clauses = array(
2413                                 'il_to' => $this->getDBkey(),
2414                                 'il_from=pr_page',
2415                                 'pr_cascade' => 1
2416                         );
2417                 } else {
2418                         $tables = array( 'templatelinks', 'page_restrictions' );
2419                         $where_clauses = array(
2420                                 'tl_namespace' => $this->getNamespace(),
2421                                 'tl_title' => $this->getDBkey(),
2422                                 'tl_from=pr_page',
2423                                 'pr_cascade' => 1
2424                         );
2425                 }
2426
2427                 if ( $getPages ) {
2428                         $cols = array( 'pr_page', 'page_namespace', 'page_title',
2429                                                    'pr_expiry', 'pr_type', 'pr_level' );
2430                         $where_clauses[] = 'page_id=pr_page';
2431                         $tables[] = 'page';
2432                 } else {
2433                         $cols = array( 'pr_expiry' );
2434                 }
2435
2436                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
2437
2438                 $sources = $getPages ? array() : false;
2439                 $now = wfTimestampNow();
2440                 $purgeExpired = false;
2441
2442                 foreach ( $res as $row ) {
2443                         $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2444                         if ( $expiry > $now ) {
2445                                 if ( $getPages ) {
2446                                         $page_id = $row->pr_page;
2447                                         $page_ns = $row->page_namespace;
2448                                         $page_title = $row->page_title;
2449                                         $sources[$page_id] = Title::makeTitle( $page_ns, $page_title );
2450                                         # Add groups needed for each restriction type if its not already there
2451                                         # Make sure this restriction type still exists
2452
2453                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
2454                                                 $pagerestrictions[$row->pr_type] = array();
2455                                         }
2456
2457                                         if ( isset( $pagerestrictions[$row->pr_type] ) &&
2458                                                  !in_array( $row->pr_level, $pagerestrictions[$row->pr_type] ) ) {
2459                                                 $pagerestrictions[$row->pr_type][] = $row->pr_level;
2460                                         }
2461                                 } else {
2462                                         $sources = true;
2463                                 }
2464                         } else {
2465                                 // Trigger lazy purge of expired restrictions from the db
2466                                 $purgeExpired = true;
2467                         }
2468                 }
2469                 if ( $purgeExpired ) {
2470                         Title::purgeExpiredRestrictions();
2471                 }
2472
2473                 if ( $getPages ) {
2474                         $this->mCascadeSources = $sources;
2475                         $this->mCascadingRestrictions = $pagerestrictions;
2476                 } else {
2477                         $this->mHasCascadingRestrictions = $sources;
2478                 }
2479
2480                 wfProfileOut( __METHOD__ );
2481                 return array( $sources, $pagerestrictions );
2482         }
2483
2484         /**
2485          * Accessor/initialisation for mRestrictions
2486          *
2487          * @param $action String action that permission needs to be checked for
2488          * @return Array of Strings the array of groups allowed to edit this article
2489          */
2490         public function getRestrictions( $action ) {
2491                 if ( !$this->mRestrictionsLoaded ) {
2492                         $this->loadRestrictions();
2493                 }
2494                 return isset( $this->mRestrictions[$action] )
2495                                 ? $this->mRestrictions[$action]
2496                                 : array();
2497         }
2498
2499         /**
2500          * Get the expiry time for the restriction against a given action
2501          *
2502          * @return String|Bool 14-char timestamp, or 'infinity' if the page is protected forever
2503          *      or not protected at all, or false if the action is not recognised.
2504          */
2505         public function getRestrictionExpiry( $action ) {
2506                 if ( !$this->mRestrictionsLoaded ) {
2507                         $this->loadRestrictions();
2508                 }
2509                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2510         }
2511
2512         /**
2513          * Returns cascading restrictions for the current article
2514          *
2515          * @return Boolean
2516          */
2517         function areRestrictionsCascading() {
2518                 if ( !$this->mRestrictionsLoaded ) {
2519                         $this->loadRestrictions();
2520                 }
2521
2522                 return $this->mCascadeRestriction;
2523         }
2524
2525         /**
2526          * Loads a string into mRestrictions array
2527          *
2528          * @param $res Resource restrictions as an SQL result.
2529          * @param $oldFashionedRestrictions String comma-separated list of page
2530          *        restrictions from page table (pre 1.10)
2531          */
2532         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
2533                 $rows = array();
2534
2535                 foreach ( $res as $row ) {
2536                         $rows[] = $row;
2537                 }
2538
2539                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
2540         }
2541
2542         /**
2543          * Compiles list of active page restrictions from both page table (pre 1.10)
2544          * and page_restrictions table for this existing page.
2545          * Public for usage by LiquidThreads.
2546          *
2547          * @param $rows array of db result objects
2548          * @param $oldFashionedRestrictions string comma-separated list of page
2549          *        restrictions from page table (pre 1.10)
2550          */
2551         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
2552                 global $wgContLang;
2553                 $dbr = wfGetDB( DB_SLAVE );
2554
2555                 $restrictionTypes = $this->getRestrictionTypes();
2556
2557                 foreach ( $restrictionTypes as $type ) {
2558                         $this->mRestrictions[$type] = array();
2559                         $this->mRestrictionsExpiry[$type] = $wgContLang->formatExpiry( '', TS_MW );
2560                 }
2561
2562                 $this->mCascadeRestriction = false;
2563
2564                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2565
2566                 if ( $oldFashionedRestrictions === null ) {
2567                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2568                                 array( 'page_id' => $this->getArticleId() ), __METHOD__ );
2569                 }
2570
2571                 if ( $oldFashionedRestrictions != '' ) {
2572
2573                         foreach ( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2574                                 $temp = explode( '=', trim( $restrict ) );
2575                                 if ( count( $temp ) == 1 ) {
2576                                         // old old format should be treated as edit/move restriction
2577                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2578                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2579                                 } else {
2580                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
2581                                 }
2582                         }
2583
2584                         $this->mOldRestrictions = true;
2585
2586                 }
2587
2588                 if ( count( $rows ) ) {
2589                         # Current system - load second to make them override.
2590                         $now = wfTimestampNow();
2591                         $purgeExpired = false;
2592
2593                         # Cycle through all the restrictions.
2594                         foreach ( $rows as $row ) {
2595
2596                                 // Don't take care of restrictions types that aren't allowed
2597                                 if ( !in_array( $row->pr_type, $restrictionTypes ) )
2598                                         continue;
2599
2600                                 // This code should be refactored, now that it's being used more generally,
2601                                 // But I don't really see any harm in leaving it in Block for now -werdna
2602                                 $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2603
2604                                 // Only apply the restrictions if they haven't expired!
2605                                 if ( !$expiry || $expiry > $now ) {
2606                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2607                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2608
2609                                         $this->mCascadeRestriction |= $row->pr_cascade;
2610                                 } else {
2611                                         // Trigger a lazy purge of expired restrictions
2612                                         $purgeExpired = true;
2613                                 }
2614                         }
2615
2616                         if ( $purgeExpired ) {
2617                                 Title::purgeExpiredRestrictions();
2618                         }
2619                 }
2620
2621                 $this->mRestrictionsLoaded = true;
2622         }
2623
2624         /**
2625          * Load restrictions from the page_restrictions table
2626          *
2627          * @param $oldFashionedRestrictions String comma-separated list of page
2628          *        restrictions from page table (pre 1.10)
2629          */
2630         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2631                 global $wgContLang;
2632                 if ( !$this->mRestrictionsLoaded ) {
2633                         if ( $this->exists() ) {
2634                                 $dbr = wfGetDB( DB_SLAVE );
2635
2636                                 $res = $dbr->select(
2637                                         'page_restrictions',
2638                                         '*',
2639                                         array( 'pr_page' => $this->getArticleId() ),
2640                                         __METHOD__
2641                                 );
2642
2643                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2644                         } else {
2645                                 $title_protection = $this->getTitleProtection();
2646
2647                                 if ( $title_protection ) {
2648                                         $now = wfTimestampNow();
2649                                         $expiry = $wgContLang->formatExpiry( $title_protection['pt_expiry'], TS_MW );
2650
2651                                         if ( !$expiry || $expiry > $now ) {
2652                                                 // Apply the restrictions
2653                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2654                                                 $this->mRestrictions['create'] = explode( ',', trim( $title_protection['pt_create_perm'] ) );
2655                                         } else { // Get rid of the old restrictions
2656                                                 Title::purgeExpiredRestrictions();
2657                                                 $this->mTitleProtection = false;
2658                                         }
2659                                 } else {
2660                                         $this->mRestrictionsExpiry['create'] = $wgContLang->formatExpiry( '', TS_MW );
2661                                 }
2662                                 $this->mRestrictionsLoaded = true;
2663                         }
2664                 }
2665         }
2666
2667         /**
2668          * Flush the protection cache in this object and force reload from the database.
2669          * This is used when updating protection from WikiPage::doUpdateRestrictions().
2670          */
2671         public function flushRestrictions() {
2672                 $this->mRestrictionsLoaded = false;
2673                 $this->mTitleProtection = null;
2674         }
2675
2676         /**
2677          * Purge expired restrictions from the page_restrictions table
2678          */
2679         static function purgeExpiredRestrictions() {
2680                 $dbw = wfGetDB( DB_MASTER );
2681                 $dbw->delete(
2682                         'page_restrictions',
2683                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2684                         __METHOD__
2685                 );
2686
2687                 $dbw->delete(
2688                         'protected_titles',
2689                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2690                         __METHOD__
2691                 );
2692         }
2693
2694         /**
2695          * Does this have subpages?  (Warning, usually requires an extra DB query.)
2696          *
2697          * @return Bool
2698          */
2699         public function hasSubpages() {
2700                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
2701                         # Duh
2702                         return false;
2703                 }
2704
2705                 # We dynamically add a member variable for the purpose of this method
2706                 # alone to cache the result.  There's no point in having it hanging
2707                 # around uninitialized in every Title object; therefore we only add it
2708                 # if needed and don't declare it statically.
2709                 if ( isset( $this->mHasSubpages ) ) {
2710                         return $this->mHasSubpages;
2711                 }
2712
2713                 $subpages = $this->getSubpages( 1 );
2714                 if ( $subpages instanceof TitleArray ) {
2715                         return $this->mHasSubpages = (bool)$subpages->count();
2716                 }
2717                 return $this->mHasSubpages = false;
2718         }
2719
2720         /**
2721          * Get all subpages of this page.
2722          *
2723          * @param $limit Int maximum number of subpages to fetch; -1 for no limit
2724          * @return mixed TitleArray, or empty array if this page's namespace
2725          *  doesn't allow subpages
2726          */
2727         public function getSubpages( $limit = -1 ) {
2728                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
2729                         return array();
2730                 }
2731
2732                 $dbr = wfGetDB( DB_SLAVE );
2733                 $conds['page_namespace'] = $this->getNamespace();
2734                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
2735                 $options = array();
2736                 if ( $limit > -1 ) {
2737                         $options['LIMIT'] = $limit;
2738                 }
2739                 return $this->mSubpages = TitleArray::newFromResult(
2740                         $dbr->select( 'page',
2741                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
2742                                 $conds,
2743                                 __METHOD__,
2744                                 $options
2745                         )
2746                 );
2747         }
2748
2749         /**
2750          * Is there a version of this page in the deletion archive?
2751          *
2752          * @return Int the number of archived revisions
2753          */
2754         public function isDeleted() {
2755                 if ( $this->getNamespace() < 0 ) {
2756                         $n = 0;
2757                 } else {
2758                         $dbr = wfGetDB( DB_SLAVE );
2759
2760                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2761                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2762                                 __METHOD__
2763                         );
2764                         if ( $this->getNamespace() == NS_FILE ) {
2765                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2766                                         array( 'fa_name' => $this->getDBkey() ),
2767                                         __METHOD__
2768                                 );
2769                         }
2770                 }
2771                 return (int)$n;
2772         }
2773
2774         /**
2775          * Is there a version of this page in the deletion archive?
2776          *
2777          * @return Boolean
2778          */
2779         public function isDeletedQuick() {
2780                 if ( $this->getNamespace() < 0 ) {
2781                         return false;
2782                 }
2783                 $dbr = wfGetDB( DB_SLAVE );
2784                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2785                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2786                         __METHOD__
2787                 );
2788                 if ( !$deleted && $this->getNamespace() == NS_FILE ) {
2789                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2790                                 array( 'fa_name' => $this->getDBkey() ),
2791                                 __METHOD__
2792                         );
2793                 }
2794                 return $deleted;
2795         }
2796
2797         /**
2798          * Get the article ID for this Title from the link cache,
2799          * adding it if necessary
2800          *
2801          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select
2802          *  for update
2803          * @return Int the ID
2804          */
2805         public function getArticleID( $flags = 0 ) {
2806                 if ( $this->getNamespace() < 0 ) {
2807                         return $this->mArticleID = 0;
2808                 }
2809                 $linkCache = LinkCache::singleton();
2810                 if ( $flags & self::GAID_FOR_UPDATE ) {
2811                         $oldUpdate = $linkCache->forUpdate( true );
2812                         $linkCache->clearLink( $this );
2813                         $this->mArticleID = $linkCache->addLinkObj( $this );
2814                         $linkCache->forUpdate( $oldUpdate );
2815                 } else {
2816                         if ( -1 == $this->mArticleID ) {
2817                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2818                         }
2819                 }
2820                 return $this->mArticleID;
2821         }
2822
2823         /**
2824          * Is this an article that is a redirect page?
2825          * Uses link cache, adding it if necessary
2826          *
2827          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2828          * @return Bool
2829          */
2830         public function isRedirect( $flags = 0 ) {
2831                 if ( !is_null( $this->mRedirect ) ) {
2832                         return $this->mRedirect;
2833                 }
2834                 # Calling getArticleID() loads the field from cache as needed
2835                 if ( !$this->getArticleID( $flags ) ) {
2836                         return $this->mRedirect = false;
2837                 }
2838                 $linkCache = LinkCache::singleton();
2839                 $this->mRedirect = (bool)$linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2840
2841                 return $this->mRedirect;
2842         }
2843
2844         /**
2845          * What is the length of this page?
2846          * Uses link cache, adding it if necessary
2847          *
2848          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2849          * @return Int
2850          */
2851         public function getLength( $flags = 0 ) {
2852                 if ( $this->mLength != -1 ) {
2853                         return $this->mLength;
2854                 }
2855                 # Calling getArticleID() loads the field from cache as needed
2856                 if ( !$this->getArticleID( $flags ) ) {
2857                         return $this->mLength = 0;
2858                 }
2859                 $linkCache = LinkCache::singleton();
2860                 $this->mLength = intval( $linkCache->getGoodLinkFieldObj( $this, 'length' ) );
2861
2862                 return $this->mLength;
2863         }
2864
2865         /**
2866          * What is the page_latest field for this page?
2867          *
2868          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2869          * @return Int or 0 if the page doesn't exist
2870          */
2871         public function getLatestRevID( $flags = 0 ) {
2872                 if ( $this->mLatestID !== false ) {
2873                         return intval( $this->mLatestID );
2874                 }
2875                 # Calling getArticleID() loads the field from cache as needed
2876                 if ( !$this->getArticleID( $flags ) ) {
2877                         return $this->mLatestID = 0;
2878                 }
2879                 $linkCache = LinkCache::singleton();
2880                 $this->mLatestID = intval( $linkCache->getGoodLinkFieldObj( $this, 'revision' ) );
2881
2882                 return $this->mLatestID;
2883         }
2884
2885         /**
2886          * This clears some fields in this object, and clears any associated
2887          * keys in the "bad links" section of the link cache.
2888          *
2889          * - This is called from WikiPage::doEdit() and WikiPage::insertOn() to allow
2890          * loading of the new page_id. It's also called from
2891          * WikiPage::doDeleteArticle()
2892          *
2893          * @param $newid Int the new Article ID
2894          */
2895         public function resetArticleID( $newid ) {
2896                 $linkCache = LinkCache::singleton();
2897                 $linkCache->clearLink( $this );
2898
2899                 if ( $newid === false ) {
2900                         $this->mArticleID = -1;
2901                 } else {
2902                         $this->mArticleID = intval( $newid );
2903                 }
2904                 $this->mRestrictionsLoaded = false;
2905                 $this->mRestrictions = array();
2906                 $this->mRedirect = null;
2907                 $this->mLength = -1;
2908                 $this->mLatestID = false;
2909                 $this->mEstimateRevisions = null;
2910         }
2911
2912         /**
2913          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
2914          *
2915          * @param $text String containing title to capitalize
2916          * @param $ns int namespace index, defaults to NS_MAIN
2917          * @return String containing capitalized title
2918          */
2919         public static function capitalize( $text, $ns = NS_MAIN ) {
2920                 global $wgContLang;
2921
2922                 if ( MWNamespace::isCapitalized( $ns ) ) {
2923                         return $wgContLang->ucfirst( $text );
2924                 } else {
2925                         return $text;
2926                 }
2927         }
2928
2929         /**
2930          * Secure and split - main initialisation function for this object
2931          *
2932          * Assumes that mDbkeyform has been set, and is urldecoded
2933          * and uses underscores, but not otherwise munged.  This function
2934          * removes illegal characters, splits off the interwiki and
2935          * namespace prefixes, sets the other forms, and canonicalizes
2936          * everything.
2937          *
2938          * @return Bool true on success
2939          */
2940         private function secureAndSplit() {
2941                 global $wgContLang, $wgLocalInterwiki;
2942
2943                 # Initialisation
2944                 $this->mInterwiki = $this->mFragment = '';
2945                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2946
2947                 $dbkey = $this->mDbkeyform;
2948
2949                 # Strip Unicode bidi override characters.
2950                 # Sometimes they slip into cut-n-pasted page titles, where the
2951                 # override chars get included in list displays.
2952                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
2953
2954                 # Clean up whitespace
2955                 # Note: use of the /u option on preg_replace here will cause
2956                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
2957                 # conveniently disabling them.
2958                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
2959                 $dbkey = trim( $dbkey, '_' );
2960
2961                 if ( $dbkey == '' ) {
2962                         return false;
2963                 }
2964
2965                 if ( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2966                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2967                         return false;
2968                 }
2969
2970                 $this->mDbkeyform = $dbkey;
2971
2972                 # Initial colon indicates main namespace rather than specified default
2973                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
2974                 if ( ':' == $dbkey[0] ) {
2975                         $this->mNamespace = NS_MAIN;
2976                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
2977                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
2978                 }
2979
2980                 # Namespace or interwiki prefix
2981                 $firstPass = true;
2982                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
2983                 do {
2984                         $m = array();
2985                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
2986                                 $p = $m[1];
2987                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
2988                                         # Ordinary namespace
2989                                         $dbkey = $m[2];
2990                                         $this->mNamespace = $ns;
2991                                         # For Talk:X pages, check if X has a "namespace" prefix
2992                                         if ( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
2993                                                 if ( $wgContLang->getNsIndex( $x[1] ) ) {
2994                                                         # Disallow Talk:File:x type titles...
2995                                                         return false;
2996                                                 } elseif ( Interwiki::isValidInterwiki( $x[1] ) ) {
2997                                                         # Disallow Talk:Interwiki:x type titles...
2998                                                         return false;
2999                                                 }
3000                                         }
3001                                 } elseif ( Interwiki::isValidInterwiki( $p ) ) {
3002                                         if ( !$firstPass ) {
3003                                                 # Can't make a local interwiki link to an interwiki link.
3004                                                 # That's just crazy!
3005                                                 return false;
3006                                         }
3007
3008                                         # Interwiki link
3009                                         $dbkey = $m[2];
3010                                         $this->mInterwiki = $wgContLang->lc( $p );
3011
3012                                         # Redundant interwiki prefix to the local wiki
3013                                         if ( $wgLocalInterwiki !== false
3014                                                 && 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) )
3015                                         {
3016                                                 if ( $dbkey == '' ) {
3017                                                         # Can't have an empty self-link
3018                                                         return false;
3019                                                 }
3020                                                 $this->mInterwiki = '';
3021                                                 $firstPass = false;
3022                                                 # Do another namespace split...
3023                                                 continue;
3024                                         }
3025
3026                                         # If there's an initial colon after the interwiki, that also
3027                                         # resets the default namespace
3028                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
3029                                                 $this->mNamespace = NS_MAIN;
3030                                                 $dbkey = substr( $dbkey, 1 );
3031                                         }
3032                                 }
3033                                 # If there's no recognized interwiki or namespace,
3034                                 # then let the colon expression be part of the title.
3035                         }
3036                         break;
3037                 } while ( true );
3038
3039                 # We already know that some pages won't be in the database!
3040                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
3041                         $this->mArticleID = 0;
3042                 }
3043                 $fragment = strstr( $dbkey, '#' );
3044                 if ( false !== $fragment ) {
3045                         $this->setFragment( $fragment );
3046                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
3047                         # remove whitespace again: prevents "Foo_bar_#"
3048                         # becoming "Foo_bar_"
3049                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
3050                 }
3051
3052                 # Reject illegal characters.
3053                 $rxTc = self::getTitleInvalidRegex();
3054                 if ( preg_match( $rxTc, $dbkey ) ) {
3055                         return false;
3056                 }
3057
3058                 # Pages with "/./" or "/../" appearing in the URLs will often be un-
3059                 # reachable due to the way web browsers deal with 'relative' URLs.
3060                 # Also, they conflict with subpage syntax.  Forbid them explicitly.
3061                 if ( strpos( $dbkey, '.' ) !== false &&
3062                          ( $dbkey === '.' || $dbkey === '..' ||
3063                            strpos( $dbkey, './' ) === 0  ||
3064                            strpos( $dbkey, '../' ) === 0 ||
3065                            strpos( $dbkey, '/./' ) !== false ||
3066                            strpos( $dbkey, '/../' ) !== false  ||
3067                            substr( $dbkey, -2 ) == '/.' ||
3068                            substr( $dbkey, -3 ) == '/..' ) )
3069                 {
3070                         return false;
3071                 }
3072
3073                 # Magic tilde sequences? Nu-uh!
3074                 if ( strpos( $dbkey, '~~~' ) !== false ) {
3075                         return false;
3076                 }
3077
3078                 # Limit the size of titles to 255 bytes. This is typically the size of the
3079                 # underlying database field. We make an exception for special pages, which
3080                 # don't need to be stored in the database, and may edge over 255 bytes due
3081                 # to subpage syntax for long titles, e.g. [[Special:Block/Long name]]
3082                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
3083                   strlen( $dbkey ) > 512 )
3084                 {
3085                         return false;
3086                 }
3087
3088                 # Normally, all wiki links are forced to have an initial capital letter so [[foo]]
3089                 # and [[Foo]] point to the same place.  Don't force it for interwikis, since the
3090                 # other site might be case-sensitive.
3091                 $this->mUserCaseDBKey = $dbkey;
3092                 if ( $this->mInterwiki == '' ) {
3093                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
3094                 }
3095
3096                 # Can't make a link to a namespace alone... "empty" local links can only be
3097                 # self-links with a fragment identifier.
3098                 if ( $dbkey == '' && $this->mInterwiki == '' && $this->mNamespace != NS_MAIN ) {
3099                         return false;
3100                 }
3101
3102                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
3103                 // IP names are not allowed for accounts, and can only be referring to
3104                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
3105                 // there are numerous ways to present the same IP. Having sp:contribs scan
3106                 // them all is silly and having some show the edits and others not is
3107                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
3108                 $dbkey = ( $this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK )
3109                         ? IP::sanitizeIP( $dbkey )
3110                         : $dbkey;
3111
3112                 // Any remaining initial :s are illegal.
3113                 if ( $dbkey !== '' && ':' == $dbkey[0] ) {
3114                         return false;
3115                 }
3116
3117                 # Fill fields
3118                 $this->mDbkeyform = $dbkey;
3119                 $this->mUrlform = wfUrlencode( $dbkey );
3120
3121                 $this->mTextform = str_replace( '_', ' ', $dbkey );
3122
3123                 return true;
3124         }
3125
3126         /**
3127          * Get an array of Title objects linking to this Title
3128          * Also stores the IDs in the link cache.
3129          *
3130          * WARNING: do not use this function on arbitrary user-supplied titles!
3131          * On heavily-used templates it will max out the memory.
3132          *
3133          * @param $options Array: may be FOR UPDATE
3134          * @param $table String: table name
3135          * @param $prefix String: fields prefix
3136          * @return Array of Title objects linking here
3137          */
3138         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3139                 if ( count( $options ) > 0 ) {
3140                         $db = wfGetDB( DB_MASTER );
3141                 } else {
3142                         $db = wfGetDB( DB_SLAVE );
3143                 }
3144
3145                 $res = $db->select(
3146                         array( 'page', $table ),
3147                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ),
3148                         array(
3149                                 "{$prefix}_from=page_id",
3150                                 "{$prefix}_namespace" => $this->getNamespace(),
3151                                 "{$prefix}_title"     => $this->getDBkey() ),
3152                         __METHOD__,
3153                         $options
3154                 );
3155
3156                 $retVal = array();
3157                 if ( $res->numRows() ) {
3158                         $linkCache = LinkCache::singleton();
3159                         foreach ( $res as $row ) {
3160                                 $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title );
3161                                 if ( $titleObj ) {
3162                                         $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3163                                         $retVal[] = $titleObj;
3164                                 }
3165                         }
3166                 }
3167                 return $retVal;
3168         }
3169
3170         /**
3171          * Get an array of Title objects using this Title as a template
3172          * Also stores the IDs in the link cache.
3173          *
3174          * WARNING: do not use this function on arbitrary user-supplied titles!
3175          * On heavily-used templates it will max out the memory.
3176          *
3177          * @param $options Array: may be FOR UPDATE
3178          * @return Array of Title the Title objects linking here
3179          */
3180         public function getTemplateLinksTo( $options = array() ) {
3181                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
3182         }
3183
3184         /**
3185          * Get an array of Title objects linked from this Title
3186          * Also stores the IDs in the link cache.
3187          *
3188          * WARNING: do not use this function on arbitrary user-supplied titles!
3189          * On heavily-used templates it will max out the memory.
3190          *
3191          * @param $options Array: may be FOR UPDATE
3192          * @param $table String: table name
3193          * @param $prefix String: fields prefix
3194          * @return Array of Title objects linking here
3195          */
3196         public function getLinksFrom( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3197                 $id = $this->getArticleId();
3198
3199                 # If the page doesn't exist; there can't be any link from this page
3200                 if ( !$id ) {
3201                         return array();
3202                 }
3203
3204                 if ( count( $options ) > 0 ) {
3205                         $db = wfGetDB( DB_MASTER );
3206                 } else {
3207                         $db = wfGetDB( DB_SLAVE );
3208                 }
3209
3210                 $namespaceFiled = "{$prefix}_namespace";
3211                 $titleField = "{$prefix}_title";
3212
3213                 $res = $db->select(
3214                         array( $table, 'page' ),
3215                         array( $namespaceFiled, $titleField, 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ),
3216                         array( "{$prefix}_from" => $id ),
3217                         __METHOD__,
3218                         $options,
3219                         array( 'page' => array( 'LEFT JOIN', array( "page_namespace=$namespaceFiled", "page_title=$titleField" ) ) )
3220                 );
3221
3222                 $retVal = array();
3223                 if ( $res->numRows() ) {
3224                         $linkCache = LinkCache::singleton();
3225                         foreach ( $res as $row ) {
3226                                 $titleObj = Title::makeTitle( $row->$namespaceFiled, $row->$titleField );
3227                                 if ( $titleObj ) {
3228                                         if ( $row->page_id ) {
3229                                                 $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3230                                         } else {
3231                                                 $linkCache->addBadLinkObj( $titleObj );
3232                                         }
3233                                         $retVal[] = $titleObj;
3234                                 }
3235                         }
3236                 }
3237                 return $retVal;
3238         }
3239
3240         /**
3241          * Get an array of Title objects used on this Title as a template
3242          * Also stores the IDs in the link cache.
3243          *
3244          * WARNING: do not use this function on arbitrary user-supplied titles!
3245          * On heavily-used templates it will max out the memory.
3246          *
3247          * @param $options Array: may be FOR UPDATE
3248          * @return Array of Title the Title objects used here
3249          */
3250         public function getTemplateLinksFrom( $options = array() ) {
3251                 return $this->getLinksFrom( $options, 'templatelinks', 'tl' );
3252         }
3253
3254         /**
3255          * Get an array of Title objects referring to non-existent articles linked from this page
3256          *
3257          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
3258          * @return Array of Title the Title objects
3259          */
3260         public function getBrokenLinksFrom() {
3261                 if ( $this->getArticleId() == 0 ) {
3262                         # All links from article ID 0 are false positives
3263                         return array();
3264                 }
3265
3266                 $dbr = wfGetDB( DB_SLAVE );
3267                 $res = $dbr->select(
3268                         array( 'page', 'pagelinks' ),
3269                         array( 'pl_namespace', 'pl_title' ),
3270                         array(
3271                                 'pl_from' => $this->getArticleId(),
3272                                 'page_namespace IS NULL'
3273                         ),
3274                         __METHOD__, array(),
3275                         array(
3276                                 'page' => array(
3277                                         'LEFT JOIN',
3278                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
3279                                 )
3280                         )
3281                 );
3282
3283                 $retVal = array();
3284                 foreach ( $res as $row ) {
3285                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
3286                 }
3287                 return $retVal;
3288         }
3289
3290
3291         /**
3292          * Get a list of URLs to purge from the Squid cache when this
3293          * page changes
3294          *
3295          * @return Array of String the URLs
3296          */
3297         public function getSquidURLs() {
3298                 global $wgContLang;
3299
3300                 $urls = array(
3301                         $this->getInternalURL(),
3302                         $this->getInternalURL( 'action=history' )
3303                 );
3304
3305                 // purge variant urls as well
3306                 if ( $wgContLang->hasVariants() ) {
3307                         $variants = $wgContLang->getVariants();
3308                         foreach ( $variants as $vCode ) {
3309                                 $urls[] = $this->getInternalURL( '', $vCode );
3310                         }
3311                 }
3312
3313                 return $urls;
3314         }
3315
3316         /**
3317          * Purge all applicable Squid URLs
3318          */
3319         public function purgeSquid() {
3320                 global $wgUseSquid;
3321                 if ( $wgUseSquid ) {
3322                         $urls = $this->getSquidURLs();
3323                         $u = new SquidUpdate( $urls );
3324                         $u->doUpdate();
3325                 }
3326         }
3327
3328         /**
3329          * Move this page without authentication
3330          *
3331          * @param $nt Title the new page Title
3332          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3333          */
3334         public function moveNoAuth( &$nt ) {
3335                 return $this->moveTo( $nt, false );
3336         }
3337
3338         /**
3339          * Check whether a given move operation would be valid.
3340          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
3341          *
3342          * @param $nt Title the new title
3343          * @param $auth Bool indicates whether $wgUser's permissions
3344          *  should be checked
3345          * @param $reason String is the log summary of the move, used for spam checking
3346          * @return Mixed True on success, getUserPermissionsErrors()-like array on failure
3347          */
3348         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
3349                 global $wgUser;
3350
3351                 $errors = array();
3352                 if ( !$nt ) {
3353                         // Normally we'd add this to $errors, but we'll get
3354                         // lots of syntax errors if $nt is not an object
3355                         return array( array( 'badtitletext' ) );
3356                 }
3357                 if ( $this->equals( $nt ) ) {
3358                         $errors[] = array( 'selfmove' );
3359                 }
3360                 if ( !$this->isMovable() ) {
3361                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
3362                 }
3363                 if ( $nt->getInterwiki() != '' ) {
3364                         $errors[] = array( 'immobile-target-namespace-iw' );
3365                 }
3366                 if ( !$nt->isMovable() ) {
3367                         $errors[] = array( 'immobile-target-namespace', $nt->getNsText() );
3368                 }
3369
3370                 $oldid = $this->getArticleID();
3371                 $newid = $nt->getArticleID();
3372
3373                 if ( strlen( $nt->getDBkey() ) < 1 ) {
3374                         $errors[] = array( 'articleexists' );
3375                 }
3376                 if ( ( $this->getDBkey() == '' ) ||
3377                          ( !$oldid ) ||
3378                          ( $nt->getDBkey() == '' ) ) {
3379                         $errors[] = array( 'badarticleerror' );
3380                 }
3381
3382                 // Image-specific checks
3383                 if ( $this->getNamespace() == NS_FILE ) {
3384                         $errors = array_merge( $errors, $this->validateFileMoveOperation( $nt ) );
3385                 }
3386
3387                 if ( $nt->getNamespace() == NS_FILE && $this->getNamespace() != NS_FILE ) {
3388                         $errors[] = array( 'nonfile-cannot-move-to-file' );
3389                 }
3390
3391                 if ( $auth ) {
3392                         $errors = wfMergeErrorArrays( $errors,
3393                                 $this->getUserPermissionsErrors( 'move', $wgUser ),
3394                                 $this->getUserPermissionsErrors( 'edit', $wgUser ),
3395                                 $nt->getUserPermissionsErrors( 'move-target', $wgUser ),
3396                                 $nt->getUserPermissionsErrors( 'edit', $wgUser ) );
3397                 }
3398
3399                 $match = EditPage::matchSummarySpamRegex( $reason );
3400                 if ( $match !== false ) {
3401                         // This is kind of lame, won't display nice
3402                         $errors[] = array( 'spamprotectiontext' );
3403                 }
3404
3405                 $err = null;
3406                 if ( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
3407                         $errors[] = array( 'hookaborted', $err );
3408                 }
3409
3410                 # The move is allowed only if (1) the target doesn't exist, or
3411                 # (2) the target is a redirect to the source, and has no history
3412                 # (so we can undo bad moves right after they're done).
3413
3414                 if ( 0 != $newid ) { # Target exists; check for validity
3415                         if ( !$this->isValidMoveTarget( $nt ) ) {
3416                                 $errors[] = array( 'articleexists' );
3417                         }
3418                 } else {
3419                         $tp = $nt->getTitleProtection();
3420                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
3421                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
3422                                 $errors[] = array( 'cantmove-titleprotected' );
3423                         }
3424                 }
3425                 if ( empty( $errors ) ) {
3426                         return true;
3427                 }
3428                 return $errors;
3429         }
3430
3431         /**
3432          * Check if the requested move target is a valid file move target
3433          * @param Title $nt Target title
3434          * @return array List of errors
3435          */
3436         protected function validateFileMoveOperation( $nt ) {
3437                 global $wgUser;
3438
3439                 $errors = array();
3440
3441                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is not allowed until below
3442
3443                 $file = wfLocalFile( $this );
3444                 if ( $file->exists() ) {
3445                         if ( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
3446                                 $errors[] = array( 'imageinvalidfilename' );
3447                         }
3448                         if ( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
3449                                 $errors[] = array( 'imagetypemismatch' );
3450                         }
3451                 }
3452
3453                 if ( $nt->getNamespace() != NS_FILE ) {
3454                         $errors[] = array( 'imagenocrossnamespace' );
3455                         // From here we want to do checks on a file object, so if we can't
3456                         // create one, we must return.
3457                         return $errors;
3458                 }
3459
3460                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is allowed below here
3461
3462                 $destFile = wfLocalFile( $nt );
3463                 if ( !$wgUser->isAllowed( 'reupload-shared' ) && !$destFile->exists() && wfFindFile( $nt ) ) {
3464                         $errors[] = array( 'file-exists-sharedrepo' );
3465                 }
3466
3467                 return $errors;
3468         }
3469
3470         /**
3471          * Move a title to a new location
3472          *
3473          * @param $nt Title the new title
3474          * @param $auth Bool indicates whether $wgUser's permissions
3475          *  should be checked
3476          * @param $reason String the reason for the move
3477          * @param $createRedirect Bool Whether to create a redirect from the old title to the new title.
3478          *  Ignored if the user doesn't have the suppressredirect right.
3479          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3480          */
3481         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
3482                 global $wgUser;
3483                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
3484                 if ( is_array( $err ) ) {
3485                         // Auto-block user's IP if the account was "hard" blocked
3486                         $wgUser->spreadAnyEditBlock();
3487                         return $err;
3488                 }
3489
3490                 // If it is a file, move it first.
3491                 // It is done before all other moving stuff is done because it's hard to revert.
3492                 $dbw = wfGetDB( DB_MASTER );
3493                 if ( $this->getNamespace() == NS_FILE ) {
3494                         $file = wfLocalFile( $this );
3495                         if ( $file->exists() ) {
3496                                 $status = $file->move( $nt );
3497                                 if ( !$status->isOk() ) {
3498                                         return $status->getErrorsArray();
3499                                 }
3500                         }
3501                         // Clear RepoGroup process cache
3502                         RepoGroup::singleton()->clearCache( $this );
3503                         RepoGroup::singleton()->clearCache( $nt ); # clear false negative cache
3504                 }
3505
3506                 $dbw->begin(); # If $file was a LocalFile, its transaction would have closed our own.
3507                 $pageid = $this->getArticleID( self::GAID_FOR_UPDATE );
3508                 $protected = $this->isProtected();
3509
3510                 // Do the actual move
3511                 $err = $this->moveToInternal( $nt, $reason, $createRedirect );
3512                 if ( is_array( $err ) ) {
3513                         # @todo FIXME: What about the File we have already moved?
3514                         $dbw->rollback();
3515                         return $err;
3516                 }
3517
3518                 // Refresh the sortkey for this row.  Be careful to avoid resetting
3519                 // cl_timestamp, which may disturb time-based lists on some sites.
3520                 $prefixes = $dbw->select(
3521                         'categorylinks',
3522                         array( 'cl_sortkey_prefix', 'cl_to' ),
3523                         array( 'cl_from' => $pageid ),
3524                         __METHOD__
3525                 );
3526                 foreach ( $prefixes as $prefixRow ) {
3527                         $prefix = $prefixRow->cl_sortkey_prefix;
3528                         $catTo = $prefixRow->cl_to;
3529                         $dbw->update( 'categorylinks',
3530                                 array(
3531                                         'cl_sortkey' => Collation::singleton()->getSortKey(
3532                                                 $nt->getCategorySortkey( $prefix ) ),
3533                                         'cl_timestamp=cl_timestamp' ),
3534                                 array(
3535                                         'cl_from' => $pageid,
3536                                         'cl_to' => $catTo ),
3537                                 __METHOD__
3538                         );
3539                 }
3540
3541                 $redirid = $this->getArticleID();
3542
3543                 if ( $protected ) {
3544                         # Protect the redirect title as the title used to be...
3545                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
3546                                 array(
3547                                         'pr_page'    => $redirid,
3548                                         'pr_type'    => 'pr_type',
3549                                         'pr_level'   => 'pr_level',
3550                                         'pr_cascade' => 'pr_cascade',
3551                                         'pr_user'    => 'pr_user',
3552                                         'pr_expiry'  => 'pr_expiry'
3553                                 ),
3554                                 array( 'pr_page' => $pageid ),
3555                                 __METHOD__,
3556                                 array( 'IGNORE' )
3557                         );
3558                         # Update the protection log
3559                         $log = new LogPage( 'protect' );
3560                         $comment = wfMsgForContent( 'prot_1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
3561                         if ( $reason ) {
3562                                 $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3563                         }
3564                         // @todo FIXME: $params?
3565                         $log->addEntry( 'move_prot', $nt, $comment, array( $this->getPrefixedText() ) );
3566                 }
3567
3568                 # Update watchlists
3569                 $oldnamespace = $this->getNamespace() & ~1;
3570                 $newnamespace = $nt->getNamespace() & ~1;
3571                 $oldtitle = $this->getDBkey();
3572                 $newtitle = $nt->getDBkey();
3573
3574                 if ( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
3575                         WatchedItem::duplicateEntries( $this, $nt );
3576                 }
3577
3578                 $dbw->commit();
3579
3580                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3581                 return true;
3582         }
3583
3584         /**
3585          * Move page to a title which is either a redirect to the
3586          * source page or nonexistent
3587          *
3588          * @param $nt Title the page to move to, which should be a redirect or nonexistent
3589          * @param $reason String The reason for the move
3590          * @param $createRedirect Bool Whether to leave a redirect at the old title.  Ignored
3591          *   if the user doesn't have the suppressredirect right
3592          */
3593         private function moveToInternal( &$nt, $reason = '', $createRedirect = true ) {
3594                 global $wgUser, $wgContLang;
3595
3596                 if ( $nt->exists() ) {
3597                         $moveOverRedirect = true;
3598                         $logType = 'move_redir';
3599                 } else {
3600                         $moveOverRedirect = false;
3601                         $logType = 'move';
3602                 }
3603
3604                 $redirectSuppressed = !$createRedirect && $wgUser->isAllowed( 'suppressredirect' );
3605
3606                 $logEntry = new ManualLogEntry( 'move', $logType );
3607                 $logEntry->setPerformer( $wgUser );
3608                 $logEntry->setTarget( $this );
3609                 $logEntry->setComment( $reason );
3610                 $logEntry->setParameters( array(
3611                         '4::target' => $nt->getPrefixedText(),
3612                         '5::noredir' => $redirectSuppressed ? '1': '0',
3613                 ) );
3614
3615                 $formatter = LogFormatter::newFromEntry( $logEntry );
3616                 $formatter->setContext( RequestContext::newExtraneousContext( $this ) );
3617                 $comment = $formatter->getPlainActionText();
3618                 if ( $reason ) {
3619                         $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3620                 }
3621                 # Truncate for whole multibyte characters.
3622                 $comment = $wgContLang->truncate( $comment, 255 );
3623
3624                 $oldid = $this->getArticleID();
3625                 $latest = $this->getLatestRevID();
3626
3627                 $dbw = wfGetDB( DB_MASTER );
3628
3629                 $newpage = WikiPage::factory( $nt );
3630
3631                 if ( $moveOverRedirect ) {
3632                         $newid = $nt->getArticleID();
3633
3634                         # Delete the old redirect. We don't save it to history since
3635                         # by definition if we've got here it's rather uninteresting.
3636                         # We have to remove it so that the next step doesn't trigger
3637                         # a conflict on the unique namespace+title index...
3638                         $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3639
3640                         $newpage->doDeleteUpdates( $newid );
3641                 }
3642
3643                 # Save a null revision in the page's history notifying of the move
3644                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3645                 if ( !is_object( $nullRevision ) ) {
3646                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3647                 }
3648                 $nullRevId = $nullRevision->insertOn( $dbw );
3649
3650                 # Change the name of the target page:
3651                 $dbw->update( 'page',
3652                         /* SET */ array(
3653                                 'page_namespace' => $nt->getNamespace(),
3654                                 'page_title'     => $nt->getDBkey(),
3655                         ),
3656                         /* WHERE */ array( 'page_id' => $oldid ),
3657                         __METHOD__
3658                 );
3659
3660                 $this->resetArticleID( 0 );
3661                 $nt->resetArticleID( $oldid );
3662
3663                 $newpage->updateRevisionOn( $dbw, $nullRevision );
3664
3665                 wfRunHooks( 'NewRevisionFromEditComplete',
3666                         array( $newpage, $nullRevision, $latest, $wgUser ) );
3667
3668                 $newpage->doEditUpdates( $nullRevision, $wgUser, array( 'changed' => false ) );
3669
3670                 # Recreate the redirect, this time in the other direction.
3671                 if ( $redirectSuppressed ) {
3672                         WikiPage::onArticleDelete( $this );
3673                 } else {
3674                         $mwRedir = MagicWord::get( 'redirect' );
3675                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3676                         $redirectArticle = WikiPage::factory( $this );
3677                         $newid = $redirectArticle->insertOn( $dbw );
3678                         if ( $newid ) { // sanity
3679                                 $redirectRevision = new Revision( array(
3680                                         'page'    => $newid,
3681                                         'comment' => $comment,
3682                                         'text'    => $redirectText ) );
3683                                 $redirectRevision->insertOn( $dbw );
3684                                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3685
3686                                 wfRunHooks( 'NewRevisionFromEditComplete',
3687                                         array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3688
3689                                 $redirectArticle->doEditUpdates( $redirectRevision, $wgUser, array( 'created' => true ) );
3690                         }
3691                 }
3692
3693                 # Log the move
3694                 $logid = $logEntry->insert();
3695                 $logEntry->publish( $logid );
3696         }
3697
3698         /**
3699          * Move this page's subpages to be subpages of $nt
3700          *
3701          * @param $nt Title Move target
3702          * @param $auth bool Whether $wgUser's permissions should be checked
3703          * @param $reason string The reason for the move
3704          * @param $createRedirect bool Whether to create redirects from the old subpages to
3705          *     the new ones Ignored if the user doesn't have the 'suppressredirect' right
3706          * @return mixed array with old page titles as keys, and strings (new page titles) or
3707          *     arrays (errors) as values, or an error array with numeric indices if no pages
3708          *     were moved
3709          */
3710         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3711                 global $wgMaximumMovedPages;
3712                 // Check permissions
3713                 if ( !$this->userCan( 'move-subpages' ) ) {
3714                         return array( 'cant-move-subpages' );
3715                 }
3716                 // Do the source and target namespaces support subpages?
3717                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
3718                         return array( 'namespace-nosubpages',
3719                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3720                 }
3721                 if ( !MWNamespace::hasSubpages( $nt->getNamespace() ) ) {
3722                         return array( 'namespace-nosubpages',
3723                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3724                 }
3725
3726                 $subpages = $this->getSubpages( $wgMaximumMovedPages + 1 );
3727                 $retval = array();
3728                 $count = 0;
3729                 foreach ( $subpages as $oldSubpage ) {
3730                         $count++;
3731                         if ( $count > $wgMaximumMovedPages ) {
3732                                 $retval[$oldSubpage->getPrefixedTitle()] =
3733                                                 array( 'movepage-max-pages',
3734                                                         $wgMaximumMovedPages );
3735                                 break;
3736                         }
3737
3738                         // We don't know whether this function was called before
3739                         // or after moving the root page, so check both
3740                         // $this and $nt
3741                         if ( $oldSubpage->getArticleId() == $this->getArticleId() ||
3742                                         $oldSubpage->getArticleID() == $nt->getArticleId() )
3743                         {
3744                                 // When moving a page to a subpage of itself,
3745                                 // don't move it twice
3746                                 continue;
3747                         }
3748                         $newPageName = preg_replace(
3749                                         '#^' . preg_quote( $this->getDBkey(), '#' ) . '#',
3750                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3751                                         $oldSubpage->getDBkey() );
3752                         if ( $oldSubpage->isTalkPage() ) {
3753                                 $newNs = $nt->getTalkPage()->getNamespace();
3754                         } else {
3755                                 $newNs = $nt->getSubjectPage()->getNamespace();
3756                         }
3757                         # Bug 14385: we need makeTitleSafe because the new page names may
3758                         # be longer than 255 characters.
3759                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3760
3761                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3762                         if ( $success === true ) {
3763                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3764                         } else {
3765                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3766                         }
3767                 }
3768                 return $retval;
3769         }
3770
3771         /**
3772          * Checks if this page is just a one-rev redirect.
3773          * Adds lock, so don't use just for light purposes.
3774          *
3775          * @return Bool
3776          */
3777         public function isSingleRevRedirect() {
3778                 $dbw = wfGetDB( DB_MASTER );
3779                 # Is it a redirect?
3780                 $row = $dbw->selectRow( 'page',
3781                         array( 'page_is_redirect', 'page_latest', 'page_id' ),
3782                         $this->pageCond(),
3783                         __METHOD__,
3784                         array( 'FOR UPDATE' )
3785                 );
3786                 # Cache some fields we may want
3787                 $this->mArticleID = $row ? intval( $row->page_id ) : 0;
3788                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3789                 $this->mLatestID = $row ? intval( $row->page_latest ) : false;
3790                 if ( !$this->mRedirect ) {
3791                         return false;
3792                 }
3793                 # Does the article have a history?
3794                 $row = $dbw->selectField( array( 'page', 'revision' ),
3795                         'rev_id',
3796                         array( 'page_namespace' => $this->getNamespace(),
3797                                 'page_title' => $this->getDBkey(),
3798                                 'page_id=rev_page',
3799                                 'page_latest != rev_id'
3800                         ),
3801                         __METHOD__,
3802                         array( 'FOR UPDATE' )
3803                 );
3804                 # Return true if there was no history
3805                 return ( $row === false );
3806         }
3807
3808         /**
3809          * Checks if $this can be moved to a given Title
3810          * - Selects for update, so don't call it unless you mean business
3811          *
3812          * @param $nt Title the new title to check
3813          * @return Bool
3814          */
3815         public function isValidMoveTarget( $nt ) {
3816                 # Is it an existing file?
3817                 if ( $nt->getNamespace() == NS_FILE ) {
3818                         $file = wfLocalFile( $nt );
3819                         if ( $file->exists() ) {
3820                                 wfDebug( __METHOD__ . ": file exists\n" );
3821                                 return false;
3822                         }
3823                 }
3824                 # Is it a redirect with no history?
3825                 if ( !$nt->isSingleRevRedirect() ) {
3826                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3827                         return false;
3828                 }
3829                 # Get the article text
3830                 $rev = Revision::newFromTitle( $nt );
3831                 if( !is_object( $rev ) ){
3832                         return false;
3833                 }
3834                 $text = $rev->getText();
3835                 # Does the redirect point to the source?
3836                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3837                 $m = array();
3838                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
3839                         $redirTitle = Title::newFromText( $m[1] );
3840                         if ( !is_object( $redirTitle ) ||
3841                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3842                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
3843                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3844                                 return false;
3845                         }
3846                 } else {
3847                         # Fail safe
3848                         wfDebug( __METHOD__ . ": failsafe\n" );
3849                         return false;
3850                 }
3851                 return true;
3852         }
3853
3854         /**
3855          * Get categories to which this Title belongs and return an array of
3856          * categories' names.
3857          *
3858          * @return Array of parents in the form:
3859          *        $parent => $currentarticle
3860          */
3861         public function getParentCategories() {
3862                 global $wgContLang;
3863
3864                 $data = array();
3865
3866                 $titleKey = $this->getArticleId();
3867
3868                 if ( $titleKey === 0 ) {
3869                         return $data;
3870                 }
3871
3872                 $dbr = wfGetDB( DB_SLAVE );
3873
3874                 $res = $dbr->select( 'categorylinks', '*',
3875                         array(
3876                                 'cl_from' => $titleKey,
3877                         ),
3878                         __METHOD__,
3879                         array()
3880                 );
3881
3882                 if ( $dbr->numRows( $res ) > 0 ) {
3883                         foreach ( $res as $row ) {
3884                                 // $data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
3885                                 $data[$wgContLang->getNSText( NS_CATEGORY ) . ':' . $row->cl_to] = $this->getFullText();
3886                         }
3887                 }
3888                 return $data;
3889         }
3890
3891         /**
3892          * Get a tree of parent categories
3893          *
3894          * @param $children Array with the children in the keys, to check for circular refs
3895          * @return Array Tree of parent categories
3896          */
3897         public function getParentCategoryTree( $children = array() ) {
3898                 $stack = array();
3899                 $parents = $this->getParentCategories();
3900
3901                 if ( $parents ) {
3902                         foreach ( $parents as $parent => $current ) {
3903                                 if ( array_key_exists( $parent, $children ) ) {
3904                                         # Circular reference
3905                                         $stack[$parent] = array();
3906                                 } else {
3907                                         $nt = Title::newFromText( $parent );
3908                                         if ( $nt ) {
3909                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array( $parent => 1 ) );
3910                                         }
3911                                 }
3912                         }
3913                 }
3914
3915                 return $stack;
3916         }
3917
3918         /**
3919          * Get an associative array for selecting this title from
3920          * the "page" table
3921          *
3922          * @return Array suitable for the $where parameter of DB::select()
3923          */
3924         public function pageCond() {
3925                 if ( $this->mArticleID > 0 ) {
3926                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
3927                         return array( 'page_id' => $this->mArticleID );
3928                 } else {
3929                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
3930                 }
3931         }
3932
3933         /**
3934          * Get the revision ID of the previous revision
3935          *
3936          * @param $revId Int Revision ID. Get the revision that was before this one.
3937          * @param $flags Int Title::GAID_FOR_UPDATE
3938          * @return Int|Bool Old revision ID, or FALSE if none exists
3939          */
3940         public function getPreviousRevisionID( $revId, $flags = 0 ) {
3941                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3942                 return $db->selectField( 'revision', 'rev_id',
3943                         array(
3944                                 'rev_page' => $this->getArticleId( $flags ),
3945                                 'rev_id < ' . intval( $revId )
3946                         ),
3947                         __METHOD__,
3948                         array( 'ORDER BY' => 'rev_id DESC' )
3949                 );
3950         }
3951
3952         /**
3953          * Get the revision ID of the next revision
3954          *
3955          * @param $revId Int Revision ID. Get the revision that was after this one.
3956          * @param $flags Int Title::GAID_FOR_UPDATE
3957          * @return Int|Bool Next revision ID, or FALSE if none exists
3958          */
3959         public function getNextRevisionID( $revId, $flags = 0 ) {
3960                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3961                 return $db->selectField( 'revision', 'rev_id',
3962                         array(
3963                                 'rev_page' => $this->getArticleId( $flags ),
3964                                 'rev_id > ' . intval( $revId )
3965                         ),
3966                         __METHOD__,
3967                         array( 'ORDER BY' => 'rev_id' )
3968                 );
3969         }
3970
3971         /**
3972          * Get the first revision of the page
3973          *
3974          * @param $flags Int Title::GAID_FOR_UPDATE
3975          * @return Revision|Null if page doesn't exist
3976          */
3977         public function getFirstRevision( $flags = 0 ) {
3978                 $pageId = $this->getArticleId( $flags );
3979                 if ( $pageId ) {
3980                         $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3981                         $row = $db->selectRow( 'revision', '*',
3982                                 array( 'rev_page' => $pageId ),
3983                                 __METHOD__,
3984                                 array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
3985                         );
3986                         if ( $row ) {
3987                                 return new Revision( $row );
3988                         }
3989                 }
3990                 return null;
3991         }
3992
3993         /**
3994          * Get the oldest revision timestamp of this page
3995          *
3996          * @param $flags Int Title::GAID_FOR_UPDATE
3997          * @return String: MW timestamp
3998          */
3999         public function getEarliestRevTime( $flags = 0 ) {
4000                 $rev = $this->getFirstRevision( $flags );
4001                 return $rev ? $rev->getTimestamp() : null;
4002         }
4003
4004         /**
4005          * Check if this is a new page
4006          *
4007          * @return bool
4008          */
4009         public function isNewPage() {
4010                 $dbr = wfGetDB( DB_SLAVE );
4011                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
4012         }
4013
4014         /**
4015          * Check whether the number of revisions of this page surpasses $wgDeleteRevisionsLimit
4016          *
4017          * @return bool
4018          */
4019         public function isBigDeletion() {
4020                 global $wgDeleteRevisionsLimit;
4021
4022                 if ( !$wgDeleteRevisionsLimit ) {
4023                         return false;
4024                 }
4025
4026                 $revCount = $this->estimateRevisionCount();
4027                 return $revCount > $wgDeleteRevisionsLimit;
4028         }
4029
4030         /**
4031          * Get the  approximate revision count of this page.
4032          *
4033          * @return int
4034          */
4035         public function estimateRevisionCount() {
4036                 if ( !$this->exists() ) {
4037                         return 0;
4038                 }
4039
4040                 if ( $this->mEstimateRevisions === null ) {
4041                         $dbr = wfGetDB( DB_SLAVE );
4042                         $this->mEstimateRevisions = $dbr->estimateRowCount( 'revision', '*',
4043                                 array( 'rev_page' => $this->getArticleId() ), __METHOD__ );
4044                 }
4045
4046                 return $this->mEstimateRevisions;
4047         }
4048
4049         /**
4050          * Get the number of revisions between the given revision.
4051          * Used for diffs and other things that really need it.
4052          *
4053          * @param $old int|Revision Old revision or rev ID (first before range)
4054          * @param $new int|Revision New revision or rev ID (first after range)
4055          * @return Int Number of revisions between these revisions.
4056          */
4057         public function countRevisionsBetween( $old, $new ) {
4058                 if ( !( $old instanceof Revision ) ) {
4059                         $old = Revision::newFromTitle( $this, (int)$old );
4060                 }
4061                 if ( !( $new instanceof Revision ) ) {
4062                         $new = Revision::newFromTitle( $this, (int)$new );
4063                 }
4064                 if ( !$old || !$new ) {
4065                         return 0; // nothing to compare
4066                 }
4067                 $dbr = wfGetDB( DB_SLAVE );
4068                 return (int)$dbr->selectField( 'revision', 'count(*)',
4069                         array(
4070                                 'rev_page' => $this->getArticleId(),
4071                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4072                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4073                         ),
4074                         __METHOD__
4075                 );
4076         }
4077
4078         /**
4079          * Get the number of authors between the given revision IDs.
4080          * Used for diffs and other things that really need it.
4081          *
4082          * @param $old int|Revision Old revision or rev ID (first before range)
4083          * @param $new int|Revision New revision or rev ID (first after range)
4084          * @param $limit Int Maximum number of authors
4085          * @return Int Number of revision authors between these revisions.
4086          */
4087         public function countAuthorsBetween( $old, $new, $limit ) {
4088                 if ( !( $old instanceof Revision ) ) {
4089                         $old = Revision::newFromTitle( $this, (int)$old );
4090                 }
4091                 if ( !( $new instanceof Revision ) ) {
4092                         $new = Revision::newFromTitle( $this, (int)$new );
4093                 }
4094                 if ( !$old || !$new ) {
4095                         return 0; // nothing to compare
4096                 }
4097                 $dbr = wfGetDB( DB_SLAVE );
4098                 $res = $dbr->select( 'revision', 'DISTINCT rev_user_text',
4099                         array(
4100                                 'rev_page' => $this->getArticleID(),
4101                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4102                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4103                         ), __METHOD__,
4104                         array( 'LIMIT' => $limit + 1 ) // add one so caller knows it was truncated
4105                 );
4106                 return (int)$dbr->numRows( $res );
4107         }
4108
4109         /**
4110          * Compare with another title.
4111          *
4112          * @param $title Title
4113          * @return Bool
4114          */
4115         public function equals( Title $title ) {
4116                 // Note: === is necessary for proper matching of number-like titles.
4117                 return $this->getInterwiki() === $title->getInterwiki()
4118                         && $this->getNamespace() == $title->getNamespace()
4119                         && $this->getDBkey() === $title->getDBkey();
4120         }
4121
4122         /**
4123          * Check if this title is a subpage of another title
4124          *
4125          * @param $title Title
4126          * @return Bool
4127          */
4128         public function isSubpageOf( Title $title ) {
4129                 return $this->getInterwiki() === $title->getInterwiki()
4130                         && $this->getNamespace() == $title->getNamespace()
4131                         && strpos( $this->getDBkey(), $title->getDBkey() . '/' ) === 0;
4132         }
4133
4134         /**
4135          * Check if page exists.  For historical reasons, this function simply
4136          * checks for the existence of the title in the page table, and will
4137          * thus return false for interwiki links, special pages and the like.
4138          * If you want to know if a title can be meaningfully viewed, you should
4139          * probably call the isKnown() method instead.
4140          *
4141          * @return Bool
4142          */
4143         public function exists() {
4144                 return $this->getArticleId() != 0;
4145         }
4146
4147         /**
4148          * Should links to this title be shown as potentially viewable (i.e. as
4149          * "bluelinks"), even if there's no record by this title in the page
4150          * table?
4151          *
4152          * This function is semi-deprecated for public use, as well as somewhat
4153          * misleadingly named.  You probably just want to call isKnown(), which
4154          * calls this function internally.
4155          *
4156          * (ISSUE: Most of these checks are cheap, but the file existence check
4157          * can potentially be quite expensive.  Including it here fixes a lot of
4158          * existing code, but we might want to add an optional parameter to skip
4159          * it and any other expensive checks.)
4160          *
4161          * @return Bool
4162          */
4163         public function isAlwaysKnown() {
4164                 if ( $this->mInterwiki != '' ) {
4165                         return true;  // any interwiki link might be viewable, for all we know
4166                 }
4167                 switch( $this->mNamespace ) {
4168                         case NS_MEDIA:
4169                         case NS_FILE:
4170                                 // file exists, possibly in a foreign repo
4171                                 return (bool)wfFindFile( $this );
4172                         case NS_SPECIAL:
4173                                 // valid special page
4174                                 return SpecialPageFactory::exists( $this->getDBkey() );
4175                         case NS_MAIN:
4176                                 // selflink, possibly with fragment
4177                                 return $this->mDbkeyform == '';
4178                         case NS_MEDIAWIKI:
4179                                 // known system message
4180                                 return $this->hasSourceText() !== false;
4181                         default:
4182                                 return false;
4183                 }
4184         }
4185
4186         /**
4187          * Does this title refer to a page that can (or might) be meaningfully
4188          * viewed?  In particular, this function may be used to determine if
4189          * links to the title should be rendered as "bluelinks" (as opposed to
4190          * "redlinks" to non-existent pages).
4191          *
4192          * @return Bool
4193          */
4194         public function isKnown() {
4195                 return $this->isAlwaysKnown() || $this->exists();
4196         }
4197
4198         /**
4199          * Does this page have source text?
4200          *
4201          * @return Boolean
4202          */
4203         public function hasSourceText() {
4204                 if ( $this->exists() ) {
4205                         return true;
4206                 }
4207
4208                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
4209                         // If the page doesn't exist but is a known system message, default
4210                         // message content will be displayed, same for language subpages-
4211                         // Use always content language to avoid loading hundreds of languages
4212                         // to get the link color.
4213                         global $wgContLang;
4214                         list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4215                         $message = wfMessage( $name )->inLanguage( $wgContLang )->useDatabase( false );
4216                         return $message->exists();
4217                 }
4218
4219                 return false;
4220         }
4221
4222         /**
4223          * Get the default message text or false if the message doesn't exist
4224          *
4225          * @return String or false
4226          */
4227         public function getDefaultMessageText() {
4228                 global $wgContLang;
4229
4230                 if ( $this->getNamespace() != NS_MEDIAWIKI ) { // Just in case
4231                         return false;
4232                 }
4233
4234                 list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4235                 $message = wfMessage( $name )->inLanguage( $lang )->useDatabase( false );
4236
4237                 if ( $message->exists() ) {
4238                         return $message->plain();
4239                 } else {
4240                         return false;
4241                 }
4242         }
4243
4244         /**
4245          * Updates page_touched for this page; called from LinksUpdate.php
4246          *
4247          * @return Bool true if the update succeded
4248          */
4249         public function invalidateCache() {
4250                 if ( wfReadOnly() ) {
4251                         return false;
4252                 }
4253                 $dbw = wfGetDB( DB_MASTER );
4254                 $success = $dbw->update(
4255                         'page',
4256                         array( 'page_touched' => $dbw->timestamp() ),
4257                         $this->pageCond(),
4258                         __METHOD__
4259                 );
4260                 HTMLFileCache::clearFileCache( $this );
4261                 return $success;
4262         }
4263
4264         /**
4265          * Update page_touched timestamps and send squid purge messages for
4266          * pages linking to this title. May be sent to the job queue depending
4267          * on the number of links. Typically called on create and delete.
4268          */
4269         public function touchLinks() {
4270                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
4271                 $u->doUpdate();
4272
4273                 if ( $this->getNamespace() == NS_CATEGORY ) {
4274                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
4275                         $u->doUpdate();
4276                 }
4277         }
4278
4279         /**
4280          * Get the last touched timestamp
4281          *
4282          * @param $db DatabaseBase: optional db
4283          * @return String last-touched timestamp
4284          */
4285         public function getTouched( $db = null ) {
4286                 $db = isset( $db ) ? $db : wfGetDB( DB_SLAVE );
4287                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
4288                 return $touched;
4289         }
4290
4291         /**
4292          * Get the timestamp when this page was updated since the user last saw it.
4293          *
4294          * @param $user User
4295          * @return String|Null
4296          */
4297         public function getNotificationTimestamp( $user = null ) {
4298                 global $wgUser, $wgShowUpdatedMarker;
4299                 // Assume current user if none given
4300                 if ( !$user ) {
4301                         $user = $wgUser;
4302                 }
4303                 // Check cache first
4304                 $uid = $user->getId();
4305                 // avoid isset here, as it'll return false for null entries
4306                 if ( array_key_exists( $uid, $this->mNotificationTimestamp ) ) {
4307                         return $this->mNotificationTimestamp[$uid];
4308                 }
4309                 if ( !$uid || !$wgShowUpdatedMarker ) {
4310                         return $this->mNotificationTimestamp[$uid] = false;
4311                 }
4312                 // Don't cache too much!
4313                 if ( count( $this->mNotificationTimestamp ) >= self::CACHE_MAX ) {
4314                         $this->mNotificationTimestamp = array();
4315                 }
4316                 $dbr = wfGetDB( DB_SLAVE );
4317                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
4318                         'wl_notificationtimestamp',
4319                         array( 'wl_namespace' => $this->getNamespace(),
4320                                 'wl_title' => $this->getDBkey(),
4321                                 'wl_user' => $user->getId()
4322                         ),
4323                         __METHOD__
4324                 );
4325                 return $this->mNotificationTimestamp[$uid];
4326         }
4327
4328         /**
4329          * Generate strings used for xml 'id' names in monobook tabs
4330          *
4331          * @param $prepend string defaults to 'nstab-'
4332          * @return String XML 'id' name
4333          */
4334         public function getNamespaceKey( $prepend = 'nstab-' ) {
4335                 global $wgContLang;
4336                 // Gets the subject namespace if this title
4337                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
4338                 // Checks if cononical namespace name exists for namespace
4339                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
4340                         // Uses canonical namespace name
4341                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
4342                 } else {
4343                         // Uses text of namespace
4344                         $namespaceKey = $this->getSubjectNsText();
4345                 }
4346                 // Makes namespace key lowercase
4347                 $namespaceKey = $wgContLang->lc( $namespaceKey );
4348                 // Uses main
4349                 if ( $namespaceKey == '' ) {
4350                         $namespaceKey = 'main';
4351                 }
4352                 // Changes file to image for backwards compatibility
4353                 if ( $namespaceKey == 'file' ) {
4354                         $namespaceKey = 'image';
4355                 }
4356                 return $prepend . $namespaceKey;
4357         }
4358
4359         /**
4360          * Get all extant redirects to this Title
4361          *
4362          * @param $ns Int|Null Single namespace to consider; NULL to consider all namespaces
4363          * @return Array of Title redirects to this title
4364          */
4365         public function getRedirectsHere( $ns = null ) {
4366                 $redirs = array();
4367
4368                 $dbr = wfGetDB( DB_SLAVE );
4369                 $where = array(
4370                         'rd_namespace' => $this->getNamespace(),
4371                         'rd_title' => $this->getDBkey(),
4372                         'rd_from = page_id'
4373                 );
4374                 if ( !is_null( $ns ) ) {
4375                         $where['page_namespace'] = $ns;
4376                 }
4377
4378                 $res = $dbr->select(
4379                         array( 'redirect', 'page' ),
4380                         array( 'page_namespace', 'page_title' ),
4381                         $where,
4382                         __METHOD__
4383                 );
4384
4385                 foreach ( $res as $row ) {
4386                         $redirs[] = self::newFromRow( $row );
4387                 }
4388                 return $redirs;
4389         }
4390
4391         /**
4392          * Check if this Title is a valid redirect target
4393          *
4394          * @return Bool
4395          */
4396         public function isValidRedirectTarget() {
4397                 global $wgInvalidRedirectTargets;
4398
4399                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
4400                 if ( $this->isSpecial( 'Userlogout' ) ) {
4401                         return false;
4402                 }
4403
4404                 foreach ( $wgInvalidRedirectTargets as $target ) {
4405                         if ( $this->isSpecial( $target ) ) {
4406                                 return false;
4407                         }
4408                 }
4409
4410                 return true;
4411         }
4412
4413         /**
4414          * Get a backlink cache object
4415          *
4416          * @return BacklinkCache
4417          */
4418         function getBacklinkCache() {
4419                 if ( is_null( $this->mBacklinkCache ) ) {
4420                         $this->mBacklinkCache = new BacklinkCache( $this );
4421                 }
4422                 return $this->mBacklinkCache;
4423         }
4424
4425         /**
4426          * Whether the magic words __INDEX__ and __NOINDEX__ function for  this page.
4427          *
4428          * @return Boolean
4429          */
4430         public function canUseNoindex() {
4431                 global $wgContentNamespaces, $wgExemptFromUserRobotsControl;
4432
4433                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
4434                         ? $wgContentNamespaces
4435                         : $wgExemptFromUserRobotsControl;
4436
4437                 return !in_array( $this->mNamespace, $bannedNamespaces );
4438
4439         }
4440
4441         /**
4442          * Returns the raw sort key to be used for categories, with the specified
4443          * prefix.  This will be fed to Collation::getSortKey() to get a
4444          * binary sortkey that can be used for actual sorting.
4445          *
4446          * @param $prefix string The prefix to be used, specified using
4447          *   {{defaultsort:}} or like [[Category:Foo|prefix]].  Empty for no
4448          *   prefix.
4449          * @return string
4450          */
4451         public function getCategorySortkey( $prefix = '' ) {
4452                 $unprefixed = $this->getText();
4453
4454                 // Anything that uses this hook should only depend
4455                 // on the Title object passed in, and should probably
4456                 // tell the users to run updateCollations.php --force
4457                 // in order to re-sort existing category relations.
4458                 wfRunHooks( 'GetDefaultSortkey', array( $this, &$unprefixed ) );
4459                 if ( $prefix !== '' ) {
4460                         # Separate with a line feed, so the unprefixed part is only used as
4461                         # a tiebreaker when two pages have the exact same prefix.
4462                         # In UCA, tab is the only character that can sort above LF
4463                         # so we strip both of them from the original prefix.
4464                         $prefix = strtr( $prefix, "\n\t", '  ' );
4465                         return "$prefix\n$unprefixed";
4466                 }
4467                 return $unprefixed;
4468         }
4469
4470         /**
4471          * Get the language in which the content of this page is written.
4472          * Defaults to $wgContLang, but in certain cases it can be e.g.
4473          * $wgLang (such as special pages, which are in the user language).
4474          *
4475          * @since 1.18
4476          * @return object Language
4477          */
4478         public function getPageLanguage() {
4479                 global $wgLang;
4480                 if ( $this->isSpecialPage() ) {
4481                         // special pages are in the user language
4482                         return $wgLang;
4483                 } elseif ( $this->isCssOrJsPage() ) {
4484                         // css/js should always be LTR and is, in fact, English
4485                         return wfGetLangObj( 'en' );
4486                 } elseif ( $this->getNamespace() == NS_MEDIAWIKI ) {
4487                         // Parse mediawiki messages with correct target language
4488                         list( /* $unused */, $lang ) = MessageCache::singleton()->figureMessage( $this->getText() );
4489                         return wfGetLangObj( $lang );
4490                 }
4491                 global $wgContLang;
4492                 // If nothing special, it should be in the wiki content language
4493                 $pageLang = $wgContLang;
4494                 // Hook at the end because we don't want to override the above stuff
4495                 wfRunHooks( 'PageContentLanguage', array( $this, &$pageLang, $wgLang ) );
4496                 return wfGetLangObj( $pageLang );
4497         }
4498 }