includes/Title.php

   1 <?php
   2 /**
   3  * Representation a title within %MediaWiki.
   4  *
   5  * See title.txt
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  20  * http://www.gnu.org/copyleft/gpl.html
  21  *
  22  * @file
  23  */
  24
  25 /**
  26  * Represents a title within MediaWiki.
  27  * Optionally may contain an interwiki designation or namespace.
  28  * @note This class can fetch various kinds of data from the database;
  29  *       however, it does so inefficiently.
  30  *
  31  * @internal documentation reviewed 15 Mar 2010
  32  */
  33 class Title {
  34         /** @name Static cache variables */
  35         // @{
  36         static private $titleCache = array();
  37         // @}
  38
  39         /**
  40          * Title::newFromText maintains a cache to avoid expensive re-normalization of
  41          * commonly used titles. On a batch operation this can become a memory leak
  42          * if not bounded. After hitting this many titles reset the cache.
  43          */
  44         const CACHE_MAX = 1000;
  45
  46         /**
  47          * Used to be GAID_FOR_UPDATE define. Used with getArticleID() and friends
  48          * to use the master DB
  49          */
  50         const GAID_FOR_UPDATE = 1;
  51
  52         /**
  53          * @name Private member variables
  54          * Please use the accessor functions instead.
  55          * @private
  56          */
  57         // @{
  58
  59         var $mTextform = '';              // /< Text form (spaces not underscores) of the main part
  60         var $mUrlform = '';               // /< URL-encoded form of the main part
  61         var $mDbkeyform = '';             // /< Main part with underscores
  62         var $mUserCaseDBKey;              // /< DB key with the initial letter in the case specified by the user
  63         var $mNamespace = NS_MAIN;        // /< Namespace index, i.e. one of the NS_xxxx constants
  64         var $mInterwiki = '';             // /< Interwiki prefix (or null string)
  65         var $mFragment;                   // /< Title fragment (i.e. the bit after the #)
  66         var $mArticleID = -1;             // /< Article ID, fetched from the link cache on demand
  67         var $mLatestID = false;           // /< ID of most recent revision
  68         var $mContentModel = false;       // /< ID of the page's content model, i.e. one of the CONTENT_MODEL_XXX constants
  69         private $mEstimateRevisions;      // /< Estimated number of revisions; null of not loaded
  70         var $mRestrictions = array();     // /< Array of groups allowed to edit this article
  71         var $mOldRestrictions = false;
  72         var $mCascadeRestriction;         ///< Cascade restrictions on this page to included templates and images?
  73         var $mCascadingRestrictions;      // Caching the results of getCascadeProtectionSources
  74         var $mRestrictionsExpiry = array(); ///< When do the restrictions on this page expire?
  75         var $mHasCascadingRestrictions;   ///< Are cascading restrictions in effect on this page?
  76         var $mCascadeSources;             ///< Where are the cascading restrictions coming from on this page?
  77         var $mRestrictionsLoaded = false; ///< Boolean for initialisation on demand
  78         var $mPrefixedText;               ///< Text form including namespace/interwiki, initialised on demand
  79         var $mTitleProtection;            ///< Cached value for getTitleProtection (create protection)
  80         # Don't change the following default, NS_MAIN is hardcoded in several
  81         # places.  See bug 696.
  82         var $mDefaultNamespace = NS_MAIN; // /< Namespace index when there is no namespace
  83                                                                           # Zero except in {{transclusion}} tags
  84         var $mWatched = null;             // /< Is $wgUser watching this page? null if unfilled, accessed through userIsWatching()
  85         var $mLength = -1;                // /< The page length, 0 for special pages
  86         var $mRedirect = null;            // /< Is the article at this title a redirect?
  87         var $mNotificationTimestamp = array(); // /< Associative array of user ID -> timestamp/false
  88         var $mHasSubpage;                 // /< Whether a page has any subpages
  89         // @}
  90
  91
  92         /**
  93          * Constructor
  94          */
  95         /*protected*/ function __construct() { }
  96
  97         /**
  98          * Create a new Title from a prefixed DB key
  99          *
 100          * @param $key String the database key, which has underscores
 101          *      instead of spaces, possibly including namespace and
 102          *      interwiki prefixes
 103          * @return Title, or NULL on an error
 104          */
 105         public static function newFromDBkey( $key ) {
 106                 $t = new Title();
 107                 $t->mDbkeyform = $key;
 108                 if ( $t->secureAndSplit() ) {
 109                         return $t;
 110                 } else {
 111                         return null;
 112                 }
 113         }
 114
 115         /**
 116          * Create a new Title from text, such as what one would find in a link. De-
 117          * codes any HTML entities in the text.
 118          *
 119          * @param $text String the link text; spaces, prefixes, and an
 120          *   initial ':' indicating the main namespace are accepted.
 121          * @param $defaultNamespace Int the namespace to use if none is speci-
 122          *   fied by a prefix.  If you want to force a specific namespace even if
 123          *   $text might begin with a namespace prefix, use makeTitle() or
 124          *   makeTitleSafe().
 125          * @throws MWException
 126          * @return Title|null - Title or null on an error.
 127          */
 128         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 129                 if ( is_object( $text ) ) {
 130                         throw new MWException( 'Title::newFromText given an object' );
 131                 }
 132
 133                 /**
 134                  * Wiki pages often contain multiple links to the same page.
 135                  * Title normalization and parsing can become expensive on
 136                  * pages with many links, so we can save a little time by
 137                  * caching them.
 138                  *
 139                  * In theory these are value objects and won't get changed...
 140                  */
 141                 if ( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 142                         return Title::$titleCache[$text];
 143                 }
 144
 145                 # Convert things like &eacute; &#257; or &#x3017; into normalized (bug 14952) text
 146                 $filteredText = Sanitizer::decodeCharReferencesAndNormalize( $text );
 147
 148                 $t = new Title();
 149                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 150                 $t->mDefaultNamespace = $defaultNamespace;
 151
 152                 static $cachedcount = 0 ;
 153                 if ( $t->secureAndSplit() ) {
 154                         if ( $defaultNamespace == NS_MAIN ) {
 155                                 if ( $cachedcount >= self::CACHE_MAX ) {
 156                                         # Avoid memory leaks on mass operations...
 157                                         Title::$titleCache = array();
 158                                         $cachedcount = 0;
 159                                 }
 160                                 $cachedcount++;
 161                                 Title::$titleCache[$text] =& $t;
 162                         }
 163                         return $t;
 164                 } else {
 165                         $ret = null;
 166                         return $ret;
 167                 }
 168         }
 169
 170         /**
 171          * THIS IS NOT THE FUNCTION YOU WANT. Use Title::newFromText().
 172          *
 173          * Example of wrong and broken code:
 174          * $title = Title::newFromURL( $wgRequest->getVal( 'title' ) );
 175          *
 176          * Example of right code:
 177          * $title = Title::newFromText( $wgRequest->getVal( 'title' ) );
 178          *
 179          * Create a new Title from URL-encoded text. Ensures that
 180          * the given title's length does not exceed the maximum.
 181          *
 182          * @param $url String the title, as might be taken from a URL
 183          * @return Title the new object, or NULL on an error
 184          */
 185         public static function newFromURL( $url ) {
 186                 $t = new Title();
 187
 188                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 189                 # but some URLs used it as a space replacement and they still come
 190                 # from some external search tools.
 191                 if ( strpos( self::legalChars(), '+' ) === false ) {
 192                         $url = str_replace( '+', ' ', $url );
 193                 }
 194
 195                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 196                 if ( $t->secureAndSplit() ) {
 197                         return $t;
 198                 } else {
 199                         return null;
 200                 }
 201         }
 202
 203         /**
 204          * Returns a list of fields that are to be selected for initializing Title objects or LinkCache entries.
 205          * Uses $wgContentHandlerUseDB to determine whether to include page_content_model.
 206          *
 207          * @return array
 208          */
 209         protected static function getSelectFields() {
 210                 global $wgContentHandlerUseDB;
 211
 212                 $fields = array(
 213                         'page_namespace', 'page_title', 'page_id',
 214                         'page_len', 'page_is_redirect', 'page_latest',
 215                 );
 216
 217                 if ( $wgContentHandlerUseDB ) {
 218                         $fields[] = 'page_content_model';
 219                 }
 220
 221                 return $fields;
 222         }
 223
 224         /**
 225          * Create a new Title from an article ID
 226          *
 227          * @param $id Int the page_id corresponding to the Title to create
 228          * @param $flags Int use Title::GAID_FOR_UPDATE to use master
 229          * @return Title the new object, or NULL on an error
 230          */
 231         public static function newFromID( $id, $flags = 0 ) {
 232                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
 233                 $row = $db->selectRow(
 234                         'page',
 235                         self::getSelectFields(),
 236                         array( 'page_id' => $id ),
 237                         __METHOD__
 238                 );
 239                 if ( $row !== false ) {
 240                         $title = Title::newFromRow( $row );
 241                 } else {
 242                         $title = null;
 243                 }
 244                 return $title;
 245         }
 246
 247         /**
 248          * Make an array of titles from an array of IDs
 249          *
 250          * @param $ids Array of Int Array of IDs
 251          * @return Array of Titles
 252          */
 253         public static function newFromIDs( $ids ) {
 254                 if ( !count( $ids ) ) {
 255                         return array();
 256                 }
 257                 $dbr = wfGetDB( DB_SLAVE );
 258
 259                 $res = $dbr->select(
 260                         'page',
 261                         self::getSelectFields(),
 262                         array( 'page_id' => $ids ),
 263                         __METHOD__
 264                 );
 265
 266                 $titles = array();
 267                 foreach ( $res as $row ) {
 268                         $titles[] = Title::newFromRow( $row );
 269                 }
 270                 return $titles;
 271         }
 272
 273         /**
 274          * Make a Title object from a DB row
 275          *
 276          * @param $row Object database row (needs at least page_title,page_namespace)
 277          * @return Title corresponding Title
 278          */
 279         public static function newFromRow( $row ) {
 280                 $t = self::makeTitle( $row->page_namespace, $row->page_title );
 281                 $t->loadFromRow( $row );
 282                 return $t;
 283         }
 284
 285         /**
 286          * Load Title object fields from a DB row.
 287          * If false is given, the title will be treated as non-existing.
 288          *
 289          * @param $row Object|bool database row
 290          */
 291         public function loadFromRow( $row ) {
 292                 if ( $row ) { // page found
 293                         if ( isset( $row->page_id ) )
 294                                 $this->mArticleID = (int)$row->page_id;
 295                         if ( isset( $row->page_len ) )
 296                                 $this->mLength = (int)$row->page_len;
 297                         if ( isset( $row->page_is_redirect ) )
 298                                 $this->mRedirect = (bool)$row->page_is_redirect;
 299                         if ( isset( $row->page_latest ) )
 300                                 $this->mLatestID = (int)$row->page_latest;
 301                         if ( isset( $row->page_content_model ) )
 302                                 $this->mContentModel = strval( $row->page_content_model );
 303                         else
 304                                 $this->mContentModel = false; # initialized lazily in getContentModel()
 305                 } else { // page not found
 306                         $this->mArticleID = 0;
 307                         $this->mLength = 0;
 308                         $this->mRedirect = false;
 309                         $this->mLatestID = 0;
 310                         $this->mContentModel = false; # initialized lazily in getContentModel()
 311                 }
 312         }
 313
 314         /**
 315          * Create a new Title from a namespace index and a DB key.
 316          * It's assumed that $ns and $title are *valid*, for instance when
 317          * they came directly from the database or a special page name.
 318          * For convenience, spaces are converted to underscores so that
 319          * eg user_text fields can be used directly.
 320          *
 321          * @param $ns Int the namespace of the article
 322          * @param $title String the unprefixed database key form
 323          * @param $fragment String the link fragment (after the "#")
 324          * @param $interwiki String the interwiki prefix
 325          * @return Title the new object
 326          */
 327         public static function &makeTitle( $ns, $title, $fragment = '', $interwiki = '' ) {
 328                 $t = new Title();
 329                 $t->mInterwiki = $interwiki;
 330                 $t->mFragment = $fragment;
 331                 $t->mNamespace = $ns = intval( $ns );
 332                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 333                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 334                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 335                 $t->mTextform = str_replace( '_', ' ', $title );
 336                 $t->mContentModel = false; # initialized lazily in getContentModel()
 337                 return $t;
 338         }
 339
 340         /**
 341          * Create a new Title from a namespace index and a DB key.
 342          * The parameters will be checked for validity, which is a bit slower
 343          * than makeTitle() but safer for user-provided data.
 344          *
 345          * @param $ns Int the namespace of the article
 346          * @param $title String database key form
 347          * @param $fragment String the link fragment (after the "#")
 348          * @param $interwiki String interwiki prefix
 349          * @return Title the new object, or NULL on an error
 350          */
 351         public static function makeTitleSafe( $ns, $title, $fragment = '', $interwiki = '' ) {
 352                 if ( !MWNamespace::exists( $ns ) ) {
 353                         return null;
 354                 }
 355
 356                 $t = new Title();
 357                 $t->mDbkeyform = Title::makeName( $ns, $title, $fragment, $interwiki );
 358                 if ( $t->secureAndSplit() ) {
 359                         return $t;
 360                 } else {
 361                         return null;
 362                 }
 363         }
 364
 365         /**
 366          * Create a new Title for the Main Page
 367          *
 368          * @return Title the new object
 369          */
 370         public static function newMainPage() {
 371                 $title = Title::newFromText( wfMessage( 'mainpage' )->inContentLanguage()->text() );
 372                 // Don't give fatal errors if the message is broken
 373                 if ( !$title ) {
 374                         $title = Title::newFromText( 'Main Page' );
 375                 }
 376                 return $title;
 377         }
 378
 379         /**
 380          * Extract a redirect destination from a string and return the
 381          * Title, or null if the text doesn't contain a valid redirect
 382          * This will only return the very next target, useful for
 383          * the redirect table and other checks that don't need full recursion
 384          *
 385          * @param $text String: Text with possible redirect
 386          * @return Title: The corresponding Title
 387          * @deprecated since 1.WD, use Content::getRedirectTarget instead.
 388          */
 389         public static function newFromRedirect( $text ) {
 390                 $content = ContentHandler::makeContent( $text, null, CONTENT_MODEL_WIKITEXT );
 391                 return $content->getRedirectTarget();
 392         }
 393
 394         /**
 395          * Extract a redirect destination from a string and return the
 396          * Title, or null if the text doesn't contain a valid redirect
 397          * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
 398          * in order to provide (hopefully) the Title of the final destination instead of another redirect
 399          *
 400          * @param $text String Text with possible redirect
 401          * @return Title
 402          * @deprecated since 1.WD, use Content::getUltimateRedirectTarget instead.
 403          */
 404         public static function newFromRedirectRecurse( $text ) {
 405                 $content = ContentHandler::makeContent( $text, null, CONTENT_MODEL_WIKITEXT );
 406                 return $content->getUltimateRedirectTarget();
 407         }
 408
 409         /**
 410          * Extract a redirect destination from a string and return an
 411          * array of Titles, or null if the text doesn't contain a valid redirect
 412          * The last element in the array is the final destination after all redirects
 413          * have been resolved (up to $wgMaxRedirects times)
 414          *
 415          * @param $text String Text with possible redirect
 416          * @return Array of Titles, with the destination last
 417          * @deprecated since 1.WD, use Content::getRedirectChain instead.
 418          */
 419         public static function newFromRedirectArray( $text ) {
 420                 $content = ContentHandler::makeContent( $text, null, CONTENT_MODEL_WIKITEXT );
 421                 return $content->getRedirectChain();
 422         }
 423
 424         /**
 425          * Get the prefixed DB key associated with an ID
 426          *
 427          * @param $id Int the page_id of the article
 428          * @return Title an object representing the article, or NULL if no such article was found
 429          */
 430         public static function nameOf( $id ) {
 431                 $dbr = wfGetDB( DB_SLAVE );
 432
 433                 $s = $dbr->selectRow(
 434                         'page',
 435                         array( 'page_namespace', 'page_title' ),
 436                         array( 'page_id' => $id ),
 437                         __METHOD__
 438                 );
 439                 if ( $s === false ) {
 440                         return null;
 441                 }
 442
 443                 $n = self::makeName( $s->page_namespace, $s->page_title );
 444                 return $n;
 445         }
 446
 447         /**
 448          * Get a regex character class describing the legal characters in a link
 449          *
 450          * @return String the list of characters, not delimited
 451          */
 452         public static function legalChars() {
 453                 global $wgLegalTitleChars;
 454                 return $wgLegalTitleChars;
 455         }
 456
 457         /**
 458          * Returns a simple regex that will match on characters and sequences invalid in titles.
 459          * Note that this doesn't pick up many things that could be wrong with titles, but that
 460          * replacing this regex with something valid will make many titles valid.
 461          *
 462          * @return String regex string
 463          */
 464         static function getTitleInvalidRegex() {
 465                 static $rxTc = false;
 466                 if ( !$rxTc ) {
 467                         # Matching titles will be held as illegal.
 468                         $rxTc = '/' .
 469                                 # Any character not allowed is forbidden...
 470                                 '[^' . self::legalChars() . ']' .
 471                                 # URL percent encoding sequences interfere with the ability
 472                                 # to round-trip titles -- you can't link to them consistently.
 473                                 '|%[0-9A-Fa-f]{2}' .
 474                                 # XML/HTML character references produce similar issues.
 475                                 '|&[A-Za-z0-9\x80-\xff]+;' .
 476                                 '|&#[0-9]+;' .
 477                                 '|&#x[0-9A-Fa-f]+;' .
 478                                 '/S';
 479                 }
 480
 481                 return $rxTc;
 482         }
 483
 484         /**
 485          * Get a string representation of a title suitable for
 486          * including in a search index
 487          *
 488          * @param $ns Int a namespace index
 489          * @param $title String text-form main part
 490          * @return String a stripped-down title string ready for the search index
 491          */
 492         public static function indexTitle( $ns, $title ) {
 493                 global $wgContLang;
 494
 495                 $lc = SearchEngine::legalSearchChars() . '&#;';
 496                 $t = $wgContLang->normalizeForSearch( $title );
 497                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 498                 $t = $wgContLang->lc( $t );
 499
 500                 # Handle 's, s'
 501                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 502                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 503
 504                 $t = preg_replace( "/\\s+/", ' ', $t );
 505
 506                 if ( $ns == NS_FILE ) {
 507                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 508                 }
 509                 return trim( $t );
 510         }
 511
 512         /**
 513          * Make a prefixed DB key from a DB key and a namespace index
 514          *
 515          * @param $ns Int numerical representation of the namespace
 516          * @param $title String the DB key form the title
 517          * @param $fragment String The link fragment (after the "#")
 518          * @param $interwiki String The interwiki prefix
 519          * @return String the prefixed form of the title
 520          */
 521         public static function makeName( $ns, $title, $fragment = '', $interwiki = '' ) {
 522                 global $wgContLang;
 523
 524                 $namespace = $wgContLang->getNsText( $ns );
 525                 $name = $namespace == '' ? $title : "$namespace:$title";
 526                 if ( strval( $interwiki ) != '' ) {
 527                         $name = "$interwiki:$name";
 528                 }
 529                 if ( strval( $fragment ) != '' ) {
 530                         $name .= '#' . $fragment;
 531                 }
 532                 return $name;
 533         }
 534
 535         /**
 536          * Escape a text fragment, say from a link, for a URL
 537          *
 538          * @param $fragment string containing a URL or link fragment (after the "#")
 539          * @return String: escaped string
 540          */
 541         static function escapeFragmentForURL( $fragment ) {
 542                 # Note that we don't urlencode the fragment.  urlencoded Unicode
 543                 # fragments appear not to work in IE (at least up to 7) or in at least
 544                 # one version of Opera 9.x.  The W3C validator, for one, doesn't seem
 545                 # to care if they aren't encoded.
 546                 return Sanitizer::escapeId( $fragment, 'noninitial' );
 547         }
 548
 549         /**
 550          * Callback for usort() to do title sorts by (namespace, title)
 551          *
 552          * @param $a Title
 553          * @param $b Title
 554          *
 555          * @return Integer: result of string comparison, or namespace comparison
 556          */
 557         public static function compare( $a, $b ) {
 558                 if ( $a->getNamespace() == $b->getNamespace() ) {
 559                         return strcmp( $a->getText(), $b->getText() );
 560                 } else {
 561                         return $a->getNamespace() - $b->getNamespace();
 562                 }
 563         }
 564
 565         /**
 566          * Determine whether the object refers to a page within
 567          * this project.
 568          *
 569          * @return Bool TRUE if this is an in-project interwiki link or a wikilink, FALSE otherwise
 570          */
 571         public function isLocal() {
 572                 if ( $this->mInterwiki != '' ) {
 573                         return Interwiki::fetch( $this->mInterwiki )->isLocal();
 574                 } else {
 575                         return true;
 576                 }
 577         }
 578
 579         /**
 580          * Is this Title interwiki?
 581          *
 582          * @return Bool
 583          */
 584         public function isExternal() {
 585                 return ( $this->mInterwiki != '' );
 586         }
 587
 588         /**
 589          * Get the interwiki prefix (or null string)
 590          *
 591          * @return String Interwiki prefix
 592          */
 593         public function getInterwiki() {
 594                 return $this->mInterwiki;
 595         }
 596
 597         /**
 598          * Determine whether the object refers to a page within
 599          * this project and is transcludable.
 600          *
 601          * @return Bool TRUE if this is transcludable
 602          */
 603         public function isTrans() {
 604                 if ( $this->mInterwiki == '' ) {
 605                         return false;
 606                 }
 607
 608                 return Interwiki::fetch( $this->mInterwiki )->isTranscludable();
 609         }
 610
 611         /**
 612          * Returns the DB name of the distant wiki which owns the object.
 613          *
 614          * @return String the DB name
 615          */
 616         public function getTransWikiID() {
 617                 if ( $this->mInterwiki == '' ) {
 618                         return false;
 619                 }
 620
 621                 return Interwiki::fetch( $this->mInterwiki )->getWikiID();
 622         }
 623
 624         /**
 625          * Get the text form (spaces not underscores) of the main part
 626          *
 627          * @return String Main part of the title
 628          */
 629         public function getText() {
 630                 return $this->mTextform;
 631         }
 632
 633         /**
 634          * Get the URL-encoded form of the main part
 635          *
 636          * @return String Main part of the title, URL-encoded
 637          */
 638         public function getPartialURL() {
 639                 return $this->mUrlform;
 640         }
 641
 642         /**
 643          * Get the main part with underscores
 644          *
 645          * @return String: Main part of the title, with underscores
 646          */
 647         public function getDBkey() {
 648                 return $this->mDbkeyform;
 649         }
 650
 651         /**
 652          * Get the DB key with the initial letter case as specified by the user
 653          *
 654          * @return String DB key
 655          */
 656         function getUserCaseDBKey() {
 657                 return $this->mUserCaseDBKey;
 658         }
 659
 660         /**
 661          * Get the namespace index, i.e. one of the NS_xxxx constants.
 662          *
 663          * @return Integer: Namespace index
 664          */
 665         public function getNamespace() {
 666                 return $this->mNamespace;
 667         }
 668
 669         /**
 670          * Get the page's content model id, see the CONTENT_MODEL_XXX constants.
 671          *
 672          * @return String: Content model id
 673          */
 674         public function getContentModel() {
 675                 if ( !$this->mContentModel ) {
 676                         $linkCache = LinkCache::singleton();
 677                         $this->mContentModel = $linkCache->getGoodLinkFieldObj( $this, 'model' );
 678                 }
 679
 680                 if ( !$this->mContentModel ) {
 681                         $this->mContentModel = ContentHandler::getDefaultModelFor( $this );
 682                 }
 683
 684                 if( !$this->mContentModel ) {
 685                         throw new MWException( "failed to determin content model!" );
 686                 }
 687
 688                 return $this->mContentModel;
 689         }
 690
 691         /**
 692          * Convenience method for checking a title's content model name
 693          *
 694          * @param int $id
 695          * @return Boolean true if $this->getContentModel() == $id
 696          */
 697         public function hasContentModel( $id ) {
 698                 return $this->getContentModel() == $id;
 699         }
 700
 701         /**
 702          * Get the namespace text
 703          *
 704          * @return String: Namespace text
 705          */
 706         public function getNsText() {
 707                 global $wgContLang;
 708
 709                 if ( $this->mInterwiki != '' ) {
 710                         // This probably shouldn't even happen. ohh man, oh yuck.
 711                         // But for interwiki transclusion it sometimes does.
 712                         // Shit. Shit shit shit.
 713                         //
 714                         // Use the canonical namespaces if possible to try to
 715                         // resolve a foreign namespace.
 716                         if ( MWNamespace::exists( $this->mNamespace ) ) {
 717                                 return MWNamespace::getCanonicalName( $this->mNamespace );
 718                         }
 719                 }
 720
 721                 if ( $wgContLang->needsGenderDistinction() &&
 722                                 MWNamespace::hasGenderDistinction( $this->mNamespace ) ) {
 723                         $gender = GenderCache::singleton()->getGenderOf( $this->getText(), __METHOD__ );
 724                         return $wgContLang->getGenderNsText( $this->mNamespace, $gender );
 725                 }
 726
 727                 return $wgContLang->getNsText( $this->mNamespace );
 728         }
 729
 730         /**
 731          * Get the namespace text of the subject (rather than talk) page
 732          *
 733          * @return String Namespace text
 734          */
 735         public function getSubjectNsText() {
 736                 global $wgContLang;
 737                 return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
 738         }
 739
 740         /**
 741          * Get the namespace text of the talk page
 742          *
 743          * @return String Namespace text
 744          */
 745         public function getTalkNsText() {
 746                 global $wgContLang;
 747                 return( $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) ) );
 748         }
 749
 750         /**
 751          * Could this title have a corresponding talk page?
 752          *
 753          * @return Bool TRUE or FALSE
 754          */
 755         public function canTalk() {
 756                 return( MWNamespace::canTalk( $this->mNamespace ) );
 757         }
 758
 759         /**
 760          * Is this in a namespace that allows actual pages?
 761          *
 762          * @return Bool
 763          * @internal note -- uses hardcoded namespace index instead of constants
 764          */
 765         public function canExist() {
 766                 return $this->mNamespace >= NS_MAIN;
 767         }
 768
 769         /**
 770          * Can this title be added to a user's watchlist?
 771          *
 772          * @return Bool TRUE or FALSE
 773          */
 774         public function isWatchable() {
 775                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
 776         }
 777
 778         /**
 779          * Returns true if this is a special page.
 780          *
 781          * @return boolean
 782          */
 783         public function isSpecialPage() {
 784                 return $this->getNamespace() == NS_SPECIAL;
 785         }
 786
 787         /**
 788          * Returns true if this title resolves to the named special page
 789          *
 790          * @param $name String The special page name
 791          * @return boolean
 792          */
 793         public function isSpecial( $name ) {
 794                 if ( $this->isSpecialPage() ) {
 795                         list( $thisName, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $this->getDBkey() );
 796                         if ( $name == $thisName ) {
 797                                 return true;
 798                         }
 799                 }
 800                 return false;
 801         }
 802
 803         /**
 804          * If the Title refers to a special page alias which is not the local default, resolve
 805          * the alias, and localise the name as necessary.  Otherwise, return $this
 806          *
 807          * @return Title
 808          */
 809         public function fixSpecialName() {
 810                 if ( $this->isSpecialPage() ) {
 811                         list( $canonicalName, $par ) = SpecialPageFactory::resolveAlias( $this->mDbkeyform );
 812                         if ( $canonicalName ) {
 813                                 $localName = SpecialPageFactory::getLocalNameFor( $canonicalName, $par );
 814                                 if ( $localName != $this->mDbkeyform ) {
 815                                         return Title::makeTitle( NS_SPECIAL, $localName );
 816                                 }
 817                         }
 818                 }
 819                 return $this;
 820         }
 821
 822         /**
 823          * Returns true if the title is inside the specified namespace.
 824          *
 825          * Please make use of this instead of comparing to getNamespace()
 826          * This function is much more resistant to changes we may make
 827          * to namespaces than code that makes direct comparisons.
 828          * @param $ns int The namespace
 829          * @return bool
 830          * @since 1.19
 831          */
 832         public function inNamespace( $ns ) {
 833                 return MWNamespace::equals( $this->getNamespace(), $ns );
 834         }
 835
 836         /**
 837          * Returns true if the title is inside one of the specified namespaces.
 838          *
 839          * @param ...$namespaces The namespaces to check for
 840          * @return bool
 841          * @since 1.19
 842          */
 843         public function inNamespaces( /* ... */ ) {
 844                 $namespaces = func_get_args();
 845                 if ( count( $namespaces ) > 0 && is_array( $namespaces[0] ) ) {
 846                         $namespaces = $namespaces[0];
 847                 }
 848
 849                 foreach ( $namespaces as $ns ) {
 850                         if ( $this->inNamespace( $ns ) ) {
 851                                 return true;
 852                         }
 853                 }
 854
 855                 return false;
 856         }
 857
 858         /**
 859          * Returns true if the title has the same subject namespace as the
 860          * namespace specified.
 861          * For example this method will take NS_USER and return true if namespace
 862          * is either NS_USER or NS_USER_TALK since both of them have NS_USER
 863          * as their subject namespace.
 864          *
 865          * This is MUCH simpler than individually testing for equivilance
 866          * against both NS_USER and NS_USER_TALK, and is also forward compatible.
 867          * @since 1.19
 868          * @param $ns int
 869          * @return bool
 870          */
 871         public function hasSubjectNamespace( $ns ) {
 872                 return MWNamespace::subjectEquals( $this->getNamespace(), $ns );
 873         }
 874
 875         /**
 876          * Is this Title in a namespace which contains content?
 877          * In other words, is this a content page, for the purposes of calculating
 878          * statistics, etc?
 879          *
 880          * @return Boolean
 881          */
 882         public function isContentPage() {
 883                 return MWNamespace::isContent( $this->getNamespace() );
 884         }
 885
 886         /**
 887          * Would anybody with sufficient privileges be able to move this page?
 888          * Some pages just aren't movable.
 889          *
 890          * @return Bool TRUE or FALSE
 891          */
 892         public function isMovable() {
 893                 if ( !MWNamespace::isMovable( $this->getNamespace() ) || $this->getInterwiki() != '' ) {
 894                         // Interwiki title or immovable namespace. Hooks don't get to override here
 895                         return false;
 896                 }
 897
 898                 $result = true;
 899                 wfRunHooks( 'TitleIsMovable', array( $this, &$result ) );
 900                 return $result;
 901         }
 902
 903         /**
 904          * Is this the mainpage?
 905          * @note Title::newFromText seams to be sufficiently optimized by the title
 906          * cache that we don't need to over-optimize by doing direct comparisons and
 907          * acidentally creating new bugs where $title->equals( Title::newFromText() )
 908          * ends up reporting something differently than $title->isMainPage();
 909          *
 910          * @since 1.18
 911          * @return Bool
 912          */
 913         public function isMainPage() {
 914                 return $this->equals( Title::newMainPage() );
 915         }
 916
 917         /**
 918          * Is this a subpage?
 919          *
 920          * @return Bool
 921          */
 922         public function isSubpage() {
 923                 return MWNamespace::hasSubpages( $this->mNamespace )
 924                         ? strpos( $this->getText(), '/' ) !== false
 925                         : false;
 926         }
 927
 928         /**
 929          * Is this a conversion table for the LanguageConverter?
 930          *
 931          * @return Bool
 932          */
 933         public function isConversionTable() {
 934                 return $this->getNamespace() == NS_MEDIAWIKI &&
 935                         strpos( $this->getText(), 'Conversiontable/' ) === 0;
 936         }
 937
 938         /**
 939          * Does that page contain wikitext, or it is JS, CSS or whatever?
 940          *
 941          * @return Bool
 942          */
 943         public function isWikitextPage() {
 944                 return $this->hasContentModel( CONTENT_MODEL_WIKITEXT );
 945         }
 946
 947         /**
 948          * Could this page contain custom CSS or JavaScript for the global UI.
 949          * This is generally true for pages in the MediaWiki namespace having CONTENT_MODEL_CSS
 950          * or CONTENT_MODEL_JAVASCRIPT.
 951          *
 952          * This method does *not* return true for per-user JS/CSS. Use isCssJsSubpage() for that!
 953          *
 954          * Note that this method should not return true for pages that contain and show "inactive" CSS or JS.
 955          *
 956          * @return Bool
 957          */
 958         public function isCssOrJsPage() {
 959                 $isCssOrJsPage = NS_MEDIAWIKI == $this->mNamespace
 960                         && ( $this->hasContentModel( CONTENT_MODEL_CSS )
 961                                 || $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
 962
 963                 #NOTE: this hook is also called in ContentHandler::getDefaultModel. It's called here again to make sure
 964                 #      hook funktions can force this method to return true even outside the mediawiki namespace.
 965
 966                 wfRunHooks( 'TitleIsCssOrJsPage', array( $this, &$isCssOrJsPage ) );
 967
 968                 return $isCssOrJsPage;
 969         }
 970
 971         /**
 972          * Is this a .css or .js subpage of a user page?
 973          * @return Bool
 974          */
 975         public function isCssJsSubpage() {
 976                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
 977                                 && ( $this->hasContentModel( CONTENT_MODEL_CSS )
 978                                         || $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) ) );
 979         }
 980
 981         /**
 982          * Trim down a .css or .js subpage title to get the corresponding skin name
 983          *
 984          * @return string containing skin name from .css or .js subpage title
 985          */
 986         public function getSkinFromCssJsSubpage() {
 987                 $subpage = explode( '/', $this->mTextform );
 988                 $subpage = $subpage[ count( $subpage ) - 1 ];
 989                 $lastdot = strrpos( $subpage, '.' );
 990                 if ( $lastdot === false )
 991                         return $subpage; # Never happens: only called for names ending in '.css' or '.js'
 992                 return substr( $subpage, 0, $lastdot );
 993         }
 994
 995         /**
 996          * Is this a .css subpage of a user page?
 997          *
 998          * @return Bool
 999          */
1000         public function isCssSubpage() {
1001                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
1002                         && $this->hasContentModel( CONTENT_MODEL_CSS ) );
1003         }
1004
1005         /**
1006          * Is this a .js subpage of a user page?
1007          *
1008          * @return Bool
1009          */
1010         public function isJsSubpage() {
1011                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
1012                         && $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
1013         }
1014
1015         /**
1016          * Is this a talk page of some sort?
1017          *
1018          * @return Bool
1019          */
1020         public function isTalkPage() {
1021                 return MWNamespace::isTalk( $this->getNamespace() );
1022         }
1023
1024         /**
1025          * Get a Title object associated with the talk page of this article
1026          *
1027          * @return Title the object for the talk page
1028          */
1029         public function getTalkPage() {
1030                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1031         }
1032
1033         /**
1034          * Get a title object associated with the subject page of this
1035          * talk page
1036          *
1037          * @return Title the object for the subject page
1038          */
1039         public function getSubjectPage() {
1040                 // Is this the same title?
1041                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
1042                 if ( $this->getNamespace() == $subjectNS ) {
1043                         return $this;
1044                 }
1045                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
1046         }
1047
1048         /**
1049          * Get the default namespace index, for when there is no namespace
1050          *
1051          * @return Int Default namespace index
1052          */
1053         public function getDefaultNamespace() {
1054                 return $this->mDefaultNamespace;
1055         }
1056
1057         /**
1058          * Get title for search index
1059          *
1060          * @return String a stripped-down title string ready for the
1061          *  search index
1062          */
1063         public function getIndexTitle() {
1064                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
1065         }
1066
1067         /**
1068          * Get the Title fragment (i.e.\ the bit after the #) in text form
1069          *
1070          * @return String Title fragment
1071          */
1072         public function getFragment() {
1073                 return $this->mFragment;
1074         }
1075
1076         /**
1077          * Get the fragment in URL form, including the "#" character if there is one
1078          * @return String Fragment in URL form
1079          */
1080         public function getFragmentForURL() {
1081                 if ( $this->mFragment == '' ) {
1082                         return '';
1083                 } else {
1084                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
1085                 }
1086         }
1087
1088         /**
1089          * Set the fragment for this title. Removes the first character from the
1090          * specified fragment before setting, so it assumes you're passing it with
1091          * an initial "#".
1092          *
1093          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
1094          * Still in active use privately.
1095          *
1096          * @param $fragment String text
1097          */
1098         public function setFragment( $fragment ) {
1099                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
1100         }
1101
1102         /**
1103          * Prefix some arbitrary text with the namespace or interwiki prefix
1104          * of this object
1105          *
1106          * @param $name String the text
1107          * @return String the prefixed text
1108          * @private
1109          */
1110         private function prefix( $name ) {
1111                 $p = '';
1112                 if ( $this->mInterwiki != '' ) {
1113                         $p = $this->mInterwiki . ':';
1114                 }
1115
1116                 if ( 0 != $this->mNamespace ) {
1117                         $p .= $this->getNsText() . ':';
1118                 }
1119                 return $p . $name;
1120         }
1121
1122         /**
1123          * Get the prefixed database key form
1124          *
1125          * @return String the prefixed title, with underscores and
1126          *  any interwiki and namespace prefixes
1127          */
1128         public function getPrefixedDBkey() {
1129                 $s = $this->prefix( $this->mDbkeyform );
1130                 $s = str_replace( ' ', '_', $s );
1131                 return $s;
1132         }
1133
1134         /**
1135          * Get the prefixed title with spaces.
1136          * This is the form usually used for display
1137          *
1138          * @return String the prefixed title, with spaces
1139          */
1140         public function getPrefixedText() {
1141                 // @todo FIXME: Bad usage of empty() ?
1142                 if ( empty( $this->mPrefixedText ) ) {
1143                         $s = $this->prefix( $this->mTextform );
1144                         $s = str_replace( '_', ' ', $s );
1145                         $this->mPrefixedText = $s;
1146                 }
1147                 return $this->mPrefixedText;
1148         }
1149
1150         /**
1151          * Return a string representation of this title
1152          *
1153          * @return String representation of this title
1154          */
1155         public function __toString() {
1156                 return $this->getPrefixedText();
1157         }
1158
1159         /**
1160          * Get the prefixed title with spaces, plus any fragment
1161          * (part beginning with '#')
1162          *
1163          * @return String the prefixed title, with spaces and the fragment, including '#'
1164          */
1165         public function getFullText() {
1166                 $text = $this->getPrefixedText();
1167                 if ( $this->mFragment != '' ) {
1168                         $text .= '#' . $this->mFragment;
1169                 }
1170                 return $text;
1171         }
1172
1173         /**
1174          * Get the base page name, i.e. the leftmost part before any slashes
1175          *
1176          * @return String Base name
1177          */
1178         public function getBaseText() {
1179                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1180                         return $this->getText();
1181                 }
1182
1183                 $parts = explode( '/', $this->getText() );
1184                 # Don't discard the real title if there's no subpage involved
1185                 if ( count( $parts ) > 1 ) {
1186                         unset( $parts[count( $parts ) - 1] );
1187                 }
1188                 return implode( '/', $parts );
1189         }
1190
1191         /**
1192          * Get the lowest-level subpage name, i.e. the rightmost part after any slashes
1193          *
1194          * @return String Subpage name
1195          */
1196         public function getSubpageText() {
1197                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1198                         return( $this->mTextform );
1199                 }
1200                 $parts = explode( '/', $this->mTextform );
1201                 return( $parts[count( $parts ) - 1] );
1202         }
1203
1204         /**
1205          * Get the HTML-escaped displayable text form.
1206          * Used for the title field in <a> tags.
1207          *
1208          * @return String the text, including any prefixes
1209          */
1210         public function getEscapedText() {
1211                 wfDeprecated( __METHOD__, '1.19' );
1212                 return htmlspecialchars( $this->getPrefixedText() );
1213         }
1214
1215         /**
1216          * Get a URL-encoded form of the subpage text
1217          *
1218          * @return String URL-encoded subpage name
1219          */
1220         public function getSubpageUrlForm() {
1221                 $text = $this->getSubpageText();
1222                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
1223                 return( $text );
1224         }
1225
1226         /**
1227          * Get a URL-encoded title (not an actual URL) including interwiki
1228          *
1229          * @return String the URL-encoded form
1230          */
1231         public function getPrefixedURL() {
1232                 $s = $this->prefix( $this->mDbkeyform );
1233                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
1234                 return $s;
1235         }
1236
1237         /**
1238          * Helper to fix up the get{Local,Full,Link,Canonical}URL args
1239          * get{Canonical,Full,Link,Local}URL methods accepted an optional
1240          * second argument named variant. This was deprecated in favor
1241          * of passing an array of option with a "variant" key
1242          * Once $query2 is removed for good, this helper can be dropped
1243          * andthe wfArrayToCGI moved to getLocalURL();
1244          *
1245          * @since 1.19 (r105919)
1246          * @param $query
1247          * @param $query2 bool
1248          * @return String
1249          */
1250         private static function fixUrlQueryArgs( $query, $query2 = false ) {
1251                 if( $query2 !== false ) {
1252                         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" );
1253                 }
1254                 if ( is_array( $query ) ) {
1255                         $query = wfArrayToCGI( $query );
1256                 }
1257                 if ( $query2 ) {
1258                         if ( is_string( $query2 ) ) {
1259                                 // $query2 is a string, we will consider this to be
1260                                 // a deprecated $variant argument and add it to the query
1261                                 $query2 = wfArrayToCGI( array( 'variant' => $query2 ) );
1262                         } else {
1263                                 $query2 = wfArrayToCGI( $query2 );
1264                         }
1265                         // If we have $query content add a & to it first
1266                         if ( $query ) {
1267                                 $query .= '&';
1268                         }
1269                         // Now append the queries together
1270                         $query .= $query2;
1271                 }
1272                 return $query;
1273         }
1274
1275         /**
1276          * Get a real URL referring to this title, with interwiki link and
1277          * fragment
1278          *
1279          * See getLocalURL for the arguments.
1280          *
1281          * @see self::getLocalURL
1282          * @see wfExpandUrl
1283          * @param $proto Protocol type to use in URL
1284          * @return String the URL
1285          */
1286         public function getFullURL( $query = '', $query2 = false, $proto = PROTO_RELATIVE ) {
1287                 $query = self::fixUrlQueryArgs( $query, $query2 );
1288
1289                 # Hand off all the decisions on urls to getLocalURL
1290                 $url = $this->getLocalURL( $query );
1291
1292                 # Expand the url to make it a full url. Note that getLocalURL has the
1293                 # potential to output full urls for a variety of reasons, so we use
1294                 # wfExpandUrl instead of simply prepending $wgServer
1295                 $url = wfExpandUrl( $url, $proto );
1296
1297                 # Finally, add the fragment.
1298                 $url .= $this->getFragmentForURL();
1299
1300                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
1301                 return $url;
1302         }
1303
1304         /**
1305          * Get a URL with no fragment or server name.  If this page is generated
1306          * with action=render, $wgServer is prepended.
1307          *
1308
1309          * @param $query string|array an optional query string,
1310          *   not used for interwiki     links. Can be specified as an associative array as well,
1311          *   e.g., array( 'action' => 'edit' ) (keys and values will be URL-escaped).
1312          *   Some query patterns will trigger various shorturl path replacements.
1313          * @param $query2 Mixed: An optional secondary query array. This one MUST
1314          *   be an array. If a string is passed it will be interpreted as a deprecated
1315          *   variant argument and urlencoded into a variant= argument.
1316          *   This second query argument will be added to the $query
1317          *   The second parameter is deprecated since 1.19. Pass it as a key,value
1318          *   pair in the first parameter array instead.
1319          *
1320          * @return String the URL
1321          */
1322         public function getLocalURL( $query = '', $query2 = false ) {
1323                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
1324
1325                 $query = self::fixUrlQueryArgs( $query, $query2 );
1326
1327                 $interwiki = Interwiki::fetch( $this->mInterwiki );
1328                 if ( $interwiki ) {
1329                         $namespace = $this->getNsText();
1330                         if ( $namespace != '' ) {
1331                                 # Can this actually happen? Interwikis shouldn't be parsed.
1332                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
1333                                 $namespace .= ':';
1334                         }
1335                         $url = $interwiki->getURL( $namespace . $this->getDBkey() );
1336                         $url = wfAppendQuery( $url, $query );
1337                 } else {
1338                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
1339                         if ( $query == '' ) {
1340                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
1341                                 wfRunHooks( 'GetLocalURL::Article', array( &$this, &$url ) );
1342                         } else {
1343                                 global $wgVariantArticlePath, $wgActionPaths;
1344                                 $url = false;
1345                                 $matches = array();
1346
1347                                 if ( !empty( $wgActionPaths ) &&
1348                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
1349                                 {
1350                                         $action = urldecode( $matches[2] );
1351                                         if ( isset( $wgActionPaths[$action] ) ) {
1352                                                 $query = $matches[1];
1353                                                 if ( isset( $matches[4] ) ) {
1354                                                         $query .= $matches[4];
1355                                                 }
1356                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
1357                                                 if ( $query != '' ) {
1358                                                         $url = wfAppendQuery( $url, $query );
1359                                                 }
1360                                         }
1361                                 }
1362
1363                                 if ( $url === false &&
1364                                         $wgVariantArticlePath &&
1365                                         $this->getPageLanguage()->hasVariants() &&
1366                                         preg_match( '/^variant=([^&]*)$/', $query, $matches ) )
1367                                 {
1368                                         $variant = urldecode( $matches[1] );
1369                                         if ( $this->getPageLanguage()->hasVariant( $variant ) ) {
1370                                                 // Only do the variant replacement if the given variant is a valid
1371                                                 // variant for the page's language.
1372                                                 $url = str_replace( '$2', urlencode( $variant ), $wgVariantArticlePath );
1373                                                 $url = str_replace( '$1', $dbkey, $url );
1374                                         }
1375                                 }
1376
1377                                 if ( $url === false ) {
1378                                         if ( $query == '-' ) {
1379                                                 $query = '';
1380                                         }
1381                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
1382                                 }
1383                         }
1384
1385                         wfRunHooks( 'GetLocalURL::Internal', array( &$this, &$url, $query ) );
1386
1387                         // @todo FIXME: This causes breakage in various places when we
1388                         // actually expected a local URL and end up with dupe prefixes.
1389                         if ( $wgRequest->getVal( 'action' ) == 'render' ) {
1390                                 $url = $wgServer . $url;
1391                         }
1392                 }
1393                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
1394                 return $url;
1395         }
1396
1397         /**
1398          * Get a URL that's the simplest URL that will be valid to link, locally,
1399          * to the current Title.  It includes the fragment, but does not include
1400          * the server unless action=render is used (or the link is external).  If
1401          * there's a fragment but the prefixed text is empty, we just return a link
1402          * to the fragment.
1403          *
1404          * The result obviously should not be URL-escaped, but does need to be
1405          * HTML-escaped if it's being output in HTML.
1406          *
1407          * See getLocalURL for the arguments.
1408          *
1409          * @see self::getLocalURL
1410          * @return String the URL
1411          */
1412         public function getLinkURL( $query = '', $query2 = false ) {
1413                 wfProfileIn( __METHOD__ );
1414                 if ( $this->isExternal() ) {
1415                         $ret = $this->getFullURL( $query, $query2 );
1416                 } elseif ( $this->getPrefixedText() === '' && $this->getFragment() !== '' ) {
1417                         $ret = $this->getFragmentForURL();
1418                 } else {
1419                         $ret = $this->getLocalURL( $query, $query2 ) . $this->getFragmentForURL();
1420                 }
1421                 wfProfileOut( __METHOD__ );
1422                 return $ret;
1423         }
1424
1425         /**
1426          * Get an HTML-escaped version of the URL form, suitable for
1427          * using in a link, without a server name or fragment
1428          *
1429          * See getLocalURL for the arguments.
1430          *
1431          * @see self::getLocalURL
1432          * @param $query string
1433          * @param $query2 bool|string
1434          * @return String the URL
1435          */
1436         public function escapeLocalURL( $query = '', $query2 = false ) {
1437                 wfDeprecated( __METHOD__, '1.19' );
1438                 return htmlspecialchars( $this->getLocalURL( $query, $query2 ) );
1439         }
1440
1441         /**
1442          * Get an HTML-escaped version of the URL form, suitable for
1443          * using in a link, including the server name and fragment
1444          *
1445          * See getLocalURL for the arguments.
1446          *
1447          * @see self::getLocalURL
1448          * @return String the URL
1449          */
1450         public function escapeFullURL( $query = '', $query2 = false ) {
1451                 wfDeprecated( __METHOD__, '1.19' );
1452                 return htmlspecialchars( $this->getFullURL( $query, $query2 ) );
1453         }
1454
1455         /**
1456          * Get the URL form for an internal link.
1457          * - Used in various Squid-related code, in case we have a different
1458          * internal hostname for the server from the exposed one.
1459          *
1460          * This uses $wgInternalServer to qualify the path, or $wgServer
1461          * if $wgInternalServer is not set. If the server variable used is
1462          * protocol-relative, the URL will be expanded to http://
1463          *
1464          * See getLocalURL for the arguments.
1465          *
1466          * @see self::getLocalURL
1467          * @return String the URL
1468          */
1469         public function getInternalURL( $query = '', $query2 = false ) {
1470                 global $wgInternalServer, $wgServer;
1471                 $query = self::fixUrlQueryArgs( $query, $query2 );
1472                 $server = $wgInternalServer !== false ? $wgInternalServer : $wgServer;
1473                 $url = wfExpandUrl( $server . $this->getLocalURL( $query ), PROTO_HTTP );
1474                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
1475                 return $url;
1476         }
1477
1478         /**
1479          * Get the URL for a canonical link, for use in things like IRC and
1480          * e-mail notifications. Uses $wgCanonicalServer and the
1481          * GetCanonicalURL hook.
1482          *
1483          * NOTE: Unlike getInternalURL(), the canonical URL includes the fragment
1484          *
1485          * See getLocalURL for the arguments.
1486          *
1487          * @see self::getLocalURL
1488          * @return string The URL
1489          * @since 1.18
1490          */
1491         public function getCanonicalURL( $query = '', $query2 = false ) {
1492                 $query = self::fixUrlQueryArgs( $query, $query2 );
1493                 $url = wfExpandUrl( $this->getLocalURL( $query ) . $this->getFragmentForURL(), PROTO_CANONICAL );
1494                 wfRunHooks( 'GetCanonicalURL', array( &$this, &$url, $query ) );
1495                 return $url;
1496         }
1497
1498         /**
1499          * HTML-escaped version of getCanonicalURL()
1500          *
1501          * See getLocalURL for the arguments.
1502          *
1503          * @see self::getLocalURL
1504          * @since 1.18
1505          * @return string
1506          */
1507         public function escapeCanonicalURL( $query = '', $query2 = false ) {
1508                 wfDeprecated( __METHOD__, '1.19' );
1509                 return htmlspecialchars( $this->getCanonicalURL( $query, $query2 ) );
1510         }
1511
1512         /**
1513          * Get the edit URL for this Title
1514          *
1515          * @return String the URL, or a null string if this is an
1516          *  interwiki link
1517          */
1518         public function getEditURL() {
1519                 if ( $this->mInterwiki != '' ) {
1520                         return '';
1521                 }
1522                 $s = $this->getLocalURL( 'action=edit' );
1523
1524                 return $s;
1525         }
1526
1527         /**
1528          * Is $wgUser watching this page?
1529          *
1530          * @deprecated in 1.20; use User::isWatched() instead.
1531          * @return Bool
1532          */
1533         public function userIsWatching() {
1534                 global $wgUser;
1535
1536                 if ( is_null( $this->mWatched ) ) {
1537                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn() ) {
1538                                 $this->mWatched = false;
1539                         } else {
1540                                 $this->mWatched = $wgUser->isWatched( $this );
1541                         }
1542                 }
1543                 return $this->mWatched;
1544         }
1545
1546         /**
1547          * Can $wgUser read this page?
1548          *
1549          * @deprecated in 1.19; use userCan(), quickUserCan() or getUserPermissionsErrors() instead
1550          * @return Bool
1551          * @todo fold these checks into userCan()
1552          */
1553         public function userCanRead() {
1554                 wfDeprecated( __METHOD__, '1.19' );
1555                 return $this->userCan( 'read' );
1556         }
1557
1558         /**
1559          * Can $user perform $action on this page?
1560          * This skips potentially expensive cascading permission checks
1561          * as well as avoids expensive error formatting
1562          *
1563          * Suitable for use for nonessential UI controls in common cases, but
1564          * _not_ for functional access control.
1565          *
1566          * May provide false positives, but should never provide a false negative.
1567          *
1568          * @param $action String action that permission needs to be checked for
1569          * @param $user User to check (since 1.19); $wgUser will be used if not
1570          *              provided.
1571          * @return Bool
1572          */
1573         public function quickUserCan( $action, $user = null ) {
1574                 return $this->userCan( $action, $user, false );
1575         }
1576
1577         /**
1578          * Can $user perform $action on this page?
1579          *
1580          * @param $action String action that permission needs to be checked for
1581          * @param $user User to check (since 1.19); $wgUser will be used if not
1582          *   provided.
1583          * @param $doExpensiveQueries Bool Set this to false to avoid doing
1584          *   unnecessary queries.
1585          * @return Bool
1586          */
1587         public function userCan( $action, $user = null, $doExpensiveQueries = true ) {
1588                 if ( !$user instanceof User ) {
1589                         global $wgUser;
1590                         $user = $wgUser;
1591                 }
1592                 return !count( $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries, true ) );
1593         }
1594
1595         /**
1596          * Can $user perform $action on this page?
1597          *
1598          * @todo FIXME: This *does not* check throttles (User::pingLimiter()).
1599          *
1600          * @param $action String action that permission needs to be checked for
1601          * @param $user User to check
1602          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary
1603          *   queries by skipping checks for cascading protections and user blocks.
1604          * @param $ignoreErrors Array of Strings Set this to a list of message keys
1605          *   whose corresponding errors may be ignored.
1606          * @return Array of arguments to wfMessage to explain permissions problems.
1607          */
1608         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1609                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1610
1611                 // Remove the errors being ignored.
1612                 foreach ( $errors as $index => $error ) {
1613                         $error_key = is_array( $error ) ? $error[0] : $error;
1614
1615                         if ( in_array( $error_key, $ignoreErrors ) ) {
1616                                 unset( $errors[$index] );
1617                         }
1618                 }
1619
1620                 return $errors;
1621         }
1622
1623         /**
1624          * Permissions checks that fail most often, and which are easiest to test.
1625          *
1626          * @param $action String the action to check
1627          * @param $user User user to check
1628          * @param $errors Array list of current errors
1629          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1630          * @param $short Boolean short circuit on first error
1631          *
1632          * @return Array list of errors
1633          */
1634         private function checkQuickPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1635                 if ( $action == 'create' ) {
1636                         if ( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1637                                  ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1638                                 $errors[] = $user->isAnon() ? array( 'nocreatetext' ) : array( 'nocreate-loggedin' );
1639                         }
1640                 } elseif ( $action == 'move' ) {
1641                         if ( !$user->isAllowed( 'move-rootuserpages' )
1642                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1643                                 // Show user page-specific message only if the user can move other pages
1644                                 $errors[] = array( 'cant-move-user-page' );
1645                         }
1646
1647                         // Check if user is allowed to move files if it's a file
1648                         if ( $this->mNamespace == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1649                                 $errors[] = array( 'movenotallowedfile' );
1650                         }
1651
1652                         if ( !$user->isAllowed( 'move' ) ) {
1653                                 // User can't move anything
1654                                 global $wgGroupPermissions;
1655                                 $userCanMove = false;
1656                                 if ( isset( $wgGroupPermissions['user']['move'] ) ) {
1657                                         $userCanMove = $wgGroupPermissions['user']['move'];
1658                                 }
1659                                 $autoconfirmedCanMove = false;
1660                                 if ( isset( $wgGroupPermissions['autoconfirmed']['move'] ) ) {
1661                                         $autoconfirmedCanMove = $wgGroupPermissions['autoconfirmed']['move'];
1662                                 }
1663                                 if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
1664                                         // custom message if logged-in users without any special rights can move
1665                                         $errors[] = array( 'movenologintext' );
1666                                 } else {
1667                                         $errors[] = array( 'movenotallowed' );
1668                                 }
1669                         }
1670                 } elseif ( $action == 'move-target' ) {
1671                         if ( !$user->isAllowed( 'move' ) ) {
1672                                 // User can't move anything
1673                                 $errors[] = array( 'movenotallowed' );
1674                         } elseif ( !$user->isAllowed( 'move-rootuserpages' )
1675                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1676                                 // Show user page-specific message only if the user can move other pages
1677                                 $errors[] = array( 'cant-move-to-user-page' );
1678                         }
1679                 } elseif ( !$user->isAllowed( $action ) ) {
1680                         $errors[] = $this->missingPermissionError( $action, $short );
1681                 }
1682
1683                 return $errors;
1684         }
1685
1686         /**
1687          * Add the resulting error code to the errors array
1688          *
1689          * @param $errors Array list of current errors
1690          * @param $result Mixed result of errors
1691          *
1692          * @return Array list of errors
1693          */
1694         private function resultToError( $errors, $result ) {
1695                 if ( is_array( $result ) && count( $result ) && !is_array( $result[0] ) ) {
1696                         // A single array representing an error
1697                         $errors[] = $result;
1698                 } elseif ( is_array( $result ) && is_array( $result[0] ) ) {
1699                         // A nested array representing multiple errors
1700                         $errors = array_merge( $errors, $result );
1701                 } elseif ( $result !== '' && is_string( $result ) ) {
1702                         // A string representing a message-id
1703                         $errors[] = array( $result );
1704                 } elseif ( $result === false ) {
1705                         // a generic "We don't want them to do that"
1706                         $errors[] = array( 'badaccess-group0' );
1707                 }
1708                 return $errors;
1709         }
1710
1711         /**
1712          * Check various permission hooks
1713          *
1714          * @param $action String the action to check
1715          * @param $user User user to check
1716          * @param $errors Array list of current errors
1717          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1718          * @param $short Boolean short circuit on first error
1719          *
1720          * @return Array list of errors
1721          */
1722         private function checkPermissionHooks( $action, $user, $errors, $doExpensiveQueries, $short ) {
1723                 // Use getUserPermissionsErrors instead
1724                 $result = '';
1725                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1726                         return $result ? array() : array( array( 'badaccess-group0' ) );
1727                 }
1728                 // Check getUserPermissionsErrors hook
1729                 if ( !wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1730                         $errors = $this->resultToError( $errors, $result );
1731                 }
1732                 // Check getUserPermissionsErrorsExpensive hook
1733                 if ( $doExpensiveQueries && !( $short && count( $errors ) > 0 ) &&
1734                          !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) ) ) {
1735                         $errors = $this->resultToError( $errors, $result );
1736                 }
1737
1738                 return $errors;
1739         }
1740
1741         /**
1742          * Check permissions on special pages & namespaces
1743          *
1744          * @param $action String the action to check
1745          * @param $user User user to check
1746          * @param $errors Array list of current errors
1747          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1748          * @param $short Boolean short circuit on first error
1749          *
1750          * @return Array list of errors
1751          */
1752         private function checkSpecialsAndNSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1753                 # Only 'createaccount' and 'execute' can be performed on
1754                 # special pages, which don't actually exist in the DB.
1755                 $specialOKActions = array( 'createaccount', 'execute', 'read' );
1756                 if ( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions ) ) {
1757                         $errors[] = array( 'ns-specialprotected' );
1758                 }
1759
1760                 # Check $wgNamespaceProtection for restricted namespaces
1761                 if ( $this->isNamespaceProtected( $user ) ) {
1762                         $ns = $this->mNamespace == NS_MAIN ?
1763                                 wfMessage( 'nstab-main' )->text() : $this->getNsText();
1764                         $errors[] = $this->mNamespace == NS_MEDIAWIKI ?
1765                                 array( 'protectedinterface' ) : array( 'namespaceprotected',  $ns );
1766                 }
1767
1768                 return $errors;
1769         }
1770
1771         /**
1772          * Check CSS/JS sub-page permissions
1773          *
1774          * @param $action String the action to check
1775          * @param $user User user to check
1776          * @param $errors Array list of current errors
1777          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1778          * @param $short Boolean short circuit on first error
1779          *
1780          * @return Array list of errors
1781          */
1782         private function checkCSSandJSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1783                 # Protect css/js subpages of user pages
1784                 # XXX: this might be better using restrictions
1785                 # XXX: right 'editusercssjs' is deprecated, for backward compatibility only
1786                 if ( $action != 'patrol' && !$user->isAllowed( 'editusercssjs' )
1787                                 && !preg_match( '/^' . preg_quote( $user->getName(), '/' ) . '\//', $this->mTextform ) ) {
1788                         if ( $this->isCssSubpage() && !$user->isAllowed( 'editusercss' ) ) {
1789                                 $errors[] = array( 'customcssprotected' );
1790                         } elseif ( $this->isJsSubpage() && !$user->isAllowed( 'edituserjs' ) ) {
1791                                 $errors[] = array( 'customjsprotected' );
1792                         }
1793                 }
1794
1795                 return $errors;
1796         }
1797
1798         /**
1799          * Check against page_restrictions table requirements on this
1800          * page. The user must possess all required rights for this
1801          * action.
1802          *
1803          * @param $action String the action to check
1804          * @param $user User user to check
1805          * @param $errors Array list of current errors
1806          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1807          * @param $short Boolean short circuit on first error
1808          *
1809          * @return Array list of errors
1810          */
1811         private function checkPageRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1812                 foreach ( $this->getRestrictions( $action ) as $right ) {
1813                         // Backwards compatibility, rewrite sysop -> protect
1814                         if ( $right == 'sysop' ) {
1815                                 $right = 'protect';
1816                         }
1817                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1818                                 // Users with 'editprotected' permission can edit protected pages
1819                                 // without cascading option turned on.
1820                                 if ( $action != 'edit' || !$user->isAllowed( 'editprotected' )
1821                                         || $this->mCascadeRestriction )
1822                                 {
1823                                         $errors[] = array( 'protectedpagetext', $right );
1824                                 }
1825                         }
1826                 }
1827
1828                 return $errors;
1829         }
1830
1831         /**
1832          * Check restrictions on cascading pages.
1833          *
1834          * @param $action String the action to check
1835          * @param $user User to check
1836          * @param $errors Array list of current errors
1837          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1838          * @param $short Boolean short circuit on first error
1839          *
1840          * @return Array list of errors
1841          */
1842         private function checkCascadingSourcesRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1843                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1844                         # We /could/ use the protection level on the source page, but it's
1845                         # fairly ugly as we have to establish a precedence hierarchy for pages
1846                         # included by multiple cascade-protected pages. So just restrict
1847                         # it to people with 'protect' permission, as they could remove the
1848                         # protection anyway.
1849                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1850                         # Cascading protection depends on more than this page...
1851                         # Several cascading protected pages may include this page...
1852                         # Check each cascading level
1853                         # This is only for protection restrictions, not for all actions
1854                         if ( isset( $restrictions[$action] ) ) {
1855                                 foreach ( $restrictions[$action] as $right ) {
1856                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1857                                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1858                                                 $pages = '';
1859                                                 foreach ( $cascadingSources as $page )
1860                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1861                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1862                                         }
1863                                 }
1864                         }
1865                 }
1866
1867                 return $errors;
1868         }
1869
1870         /**
1871          * Check action permissions not already checked in checkQuickPermissions
1872          *
1873          * @param $action String the action to check
1874          * @param $user User to check
1875          * @param $errors Array list of current errors
1876          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1877          * @param $short Boolean short circuit on first error
1878          *
1879          * @return Array list of errors
1880          */
1881         private function checkActionPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1882                 global $wgDeleteRevisionsLimit, $wgLang;
1883
1884                 if ( $action == 'protect' ) {
1885                         if ( count( $this->getUserPermissionsErrorsInternal( 'edit', $user, $doExpensiveQueries, true ) ) ) {
1886                                 // If they can't edit, they shouldn't protect.
1887                                 $errors[] = array( 'protect-cantedit' );
1888                         }
1889                 } elseif ( $action == 'create' ) {
1890                         $title_protection = $this->getTitleProtection();
1891                         if( $title_protection ) {
1892                                 if( $title_protection['pt_create_perm'] == 'sysop' ) {
1893                                         $title_protection['pt_create_perm'] = 'protect'; // B/C
1894                                 }
1895                                 if( $title_protection['pt_create_perm'] == '' ||
1896                                         !$user->isAllowed( $title_protection['pt_create_perm'] ) )
1897                                 {
1898                                         $errors[] = array( 'titleprotected', User::whoIs( $title_protection['pt_user'] ), $title_protection['pt_reason'] );
1899                                 }
1900                         }
1901                 } elseif ( $action == 'move' ) {
1902                         // Check for immobile pages
1903                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1904                                 // Specific message for this case
1905                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1906                         } elseif ( !$this->isMovable() ) {
1907                                 // Less specific message for rarer cases
1908                                 $errors[] = array( 'immobile-source-page' );
1909                         }
1910                 } elseif ( $action == 'move-target' ) {
1911                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1912                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1913                         } elseif ( !$this->isMovable() ) {
1914                                 $errors[] = array( 'immobile-target-page' );
1915                         }
1916                 } elseif ( $action == 'delete' ) {
1917                         if ( $doExpensiveQueries && $wgDeleteRevisionsLimit
1918                                 && !$this->userCan( 'bigdelete', $user ) && $this->isBigDeletion() )
1919                         {
1920                                 $errors[] = array( 'delete-toobig', $wgLang->formatNum( $wgDeleteRevisionsLimit ) );
1921                         }
1922                 }
1923                 return $errors;
1924         }
1925
1926         /**
1927          * Check that the user isn't blocked from editting.
1928          *
1929          * @param $action String the action to check
1930          * @param $user User to check
1931          * @param $errors Array list of current errors
1932          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1933          * @param $short Boolean short circuit on first error
1934          *
1935          * @return Array list of errors
1936          */
1937         private function checkUserBlock( $action, $user, $errors, $doExpensiveQueries, $short ) {
1938                 // Account creation blocks handled at userlogin.
1939                 // Unblocking handled in SpecialUnblock
1940                 if( !$doExpensiveQueries || in_array( $action, array( 'createaccount', 'unblock' ) ) ) {
1941                         return $errors;
1942                 }
1943
1944                 global $wgContLang, $wgLang, $wgEmailConfirmToEdit;
1945
1946                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() ) {
1947                         $errors[] = array( 'confirmedittext' );
1948                 }
1949
1950                 if ( ( $action == 'edit' || $action == 'create' ) && !$user->isBlockedFrom( $this ) ) {
1951                         // Don't block the user from editing their own talk page unless they've been
1952                         // explicitly blocked from that too.
1953                 } elseif( $user->isBlocked() && $user->mBlock->prevents( $action ) !== false ) {
1954                         $block = $user->getBlock();
1955
1956                         // This is from OutputPage::blockedPage
1957                         // Copied at r23888 by werdna
1958
1959                         $id = $user->blockedBy();
1960                         $reason = $user->blockedFor();
1961                         if ( $reason == '' ) {
1962                                 $reason = wfMessage( 'blockednoreason' )->text();
1963                         }
1964                         $ip = $user->getRequest()->getIP();
1965
1966                         if ( is_numeric( $id ) ) {
1967                                 $name = User::whoIs( $id );
1968                         } else {
1969                                 $name = $id;
1970                         }
1971
1972                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1973                         $blockid = $block->getId();
1974                         $blockExpiry = $block->getExpiry();
1975                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $block->mTimestamp ), true );
1976                         if ( $blockExpiry == 'infinity' ) {
1977                                 $blockExpiry = wfMessage( 'infiniteblock' )->text();
1978                         } else {
1979                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1980                         }
1981
1982                         $intended = strval( $block->getTarget() );
1983
1984                         $errors[] = array( ( $block->mAuto ? 'autoblockedtext' : 'blockedtext' ), $link, $reason, $ip, $name,
1985                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
1986                 }
1987
1988                 return $errors;
1989         }
1990
1991         /**
1992          * Check that the user is allowed to read this page.
1993          *
1994          * @param $action String the action to check
1995          * @param $user User to check
1996          * @param $errors Array list of current errors
1997          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1998          * @param $short Boolean short circuit on first error
1999          *
2000          * @return Array list of errors
2001          */
2002         private function checkReadPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
2003                 global $wgWhitelistRead, $wgGroupPermissions, $wgRevokePermissions;
2004                 static $useShortcut = null;
2005
2006                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
2007                 if ( is_null( $useShortcut ) ) {
2008                         $useShortcut = true;
2009                         if ( empty( $wgGroupPermissions['*']['read'] ) ) {
2010                                 # Not a public wiki, so no shortcut
2011                                 $useShortcut = false;
2012                         } elseif ( !empty( $wgRevokePermissions ) ) {
2013                                 /**
2014                                  * Iterate through each group with permissions being revoked (key not included since we don't care
2015                                  * what the group name is), then check if the read permission is being revoked. If it is, then
2016                                  * we don't use the shortcut below since the user might not be able to read, even though anon
2017                                  * reading is allowed.
2018                                  */
2019                                 foreach ( $wgRevokePermissions as $perms ) {
2020                                         if ( !empty( $perms['read'] ) ) {
2021                                                 # We might be removing the read right from the user, so no shortcut
2022                                                 $useShortcut = false;
2023                                                 break;
2024                                         }
2025                                 }
2026                         }
2027                 }
2028
2029                 $whitelisted = false;
2030                 if ( $useShortcut ) {
2031                         # Shortcut for public wikis, allows skipping quite a bit of code
2032                         $whitelisted = true;
2033                 } elseif ( $user->isAllowed( 'read' ) ) {
2034                         # If the user is allowed to read pages, he is allowed to read all pages
2035                         $whitelisted = true;
2036                 } elseif ( $this->isSpecial( 'Userlogin' )
2037                         || $this->isSpecial( 'ChangePassword' )
2038                         || $this->isSpecial( 'PasswordReset' )
2039                 ) {
2040                         # Always grant access to the login page.
2041                         # Even anons need to be able to log in.
2042                         $whitelisted = true;
2043                 } elseif ( is_array( $wgWhitelistRead ) && count( $wgWhitelistRead ) ) {
2044                         # Time to check the whitelist
2045                         # Only do these checks is there's something to check against
2046                         $name = $this->getPrefixedText();
2047                         $dbName = $this->getPrefixedDBKey();
2048
2049                         // Check for explicit whitelisting with and without underscores
2050                         if ( in_array( $name, $wgWhitelistRead, true ) || in_array( $dbName, $wgWhitelistRead, true ) ) {
2051                                 $whitelisted = true;
2052                         } elseif ( $this->getNamespace() == NS_MAIN ) {
2053                                 # Old settings might have the title prefixed with
2054                                 # a colon for main-namespace pages
2055                                 if ( in_array( ':' . $name, $wgWhitelistRead ) ) {
2056                                         $whitelisted = true;
2057                                 }
2058                         } elseif ( $this->isSpecialPage() ) {
2059                                 # If it's a special page, ditch the subpage bit and check again
2060                                 $name = $this->getDBkey();
2061                                 list( $name, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $name );
2062                                 if ( $name !== false ) {
2063                                         $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
2064                                         if ( in_array( $pure, $wgWhitelistRead, true ) ) {
2065                                                 $whitelisted = true;
2066                                         }
2067                                 }
2068                         }
2069                 }
2070
2071                 if ( !$whitelisted ) {
2072                         # If the title is not whitelisted, give extensions a chance to do so...
2073                         wfRunHooks( 'TitleReadWhitelist', array( $this, $user, &$whitelisted ) );
2074                         if ( !$whitelisted ) {
2075                                 $errors[] = $this->missingPermissionError( $action, $short );
2076                         }
2077                 }
2078
2079                 return $errors;
2080         }
2081
2082         /**
2083          * Get a description array when the user doesn't have the right to perform
2084          * $action (i.e. when User::isAllowed() returns false)
2085          *
2086          * @param $action String the action to check
2087          * @param $short Boolean short circuit on first error
2088          * @return Array list of errors
2089          */
2090         private function missingPermissionError( $action, $short ) {
2091                 // We avoid expensive display logic for quickUserCan's and such
2092                 if ( $short ) {
2093                         return array( 'badaccess-group0' );
2094                 }
2095
2096                 $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
2097                         User::getGroupsWithPermission( $action ) );
2098
2099                 if ( count( $groups ) ) {
2100                         global $wgLang;
2101                         return array(
2102                                 'badaccess-groups',
2103                                 $wgLang->commaList( $groups ),
2104                                 count( $groups )
2105                         );
2106                 } else {
2107                         return array( 'badaccess-group0' );
2108                 }
2109         }
2110
2111         /**
2112          * Can $user perform $action on this page? This is an internal function,
2113          * which checks ONLY that previously checked by userCan (i.e. it leaves out
2114          * checks on wfReadOnly() and blocks)
2115          *
2116          * @param $action String action that permission needs to be checked for
2117          * @param $user User to check
2118          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary queries.
2119          * @param $short Bool Set this to true to stop after the first permission error.
2120          * @return Array of arrays of the arguments to wfMessage to explain permissions problems.
2121          */
2122         protected function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true, $short = false ) {
2123                 wfProfileIn( __METHOD__ );
2124
2125                 # Read has special handling
2126                 if ( $action == 'read' ) {
2127                         $checks = array(
2128                                 'checkPermissionHooks',
2129                                 'checkReadPermissions',
2130                         );
2131                 } else {
2132                         $checks = array(
2133                                 'checkQuickPermissions',
2134                                 'checkPermissionHooks',
2135                                 'checkSpecialsAndNSPermissions',
2136                                 'checkCSSandJSPermissions',
2137                                 'checkPageRestrictions',
2138                                 'checkCascadingSourcesRestrictions',
2139                                 'checkActionPermissions',
2140                                 'checkUserBlock'
2141                         );
2142                 }
2143
2144                 $errors = array();
2145                 while( count( $checks ) > 0 &&
2146                                 !( $short && count( $errors ) > 0 ) ) {
2147                         $method = array_shift( $checks );
2148                         $errors = $this->$method( $action, $user, $errors, $doExpensiveQueries, $short );
2149                 }
2150
2151                 wfProfileOut( __METHOD__ );
2152                 return $errors;
2153         }
2154
2155         /**
2156          * Protect css subpages of user pages: can $wgUser edit
2157          * this page?
2158          *
2159          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2160          * @return Bool
2161          */
2162         public function userCanEditCssSubpage() {
2163                 global $wgUser;
2164                 wfDeprecated( __METHOD__, '1.19' );
2165                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'editusercss' ) )
2166                         || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2167         }
2168
2169         /**
2170          * Protect js subpages of user pages: can $wgUser edit
2171          * this page?
2172          *
2173          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2174          * @return Bool
2175          */
2176         public function userCanEditJsSubpage() {
2177                 global $wgUser;
2178                 wfDeprecated( __METHOD__, '1.19' );
2179                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'edituserjs' ) )
2180                            || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2181         }
2182
2183         /**
2184          * Get a filtered list of all restriction types supported by this wiki.
2185          * @param bool $exists True to get all restriction types that apply to
2186          * titles that do exist, False for all restriction types that apply to
2187          * titles that do not exist
2188          * @return array
2189          */
2190         public static function getFilteredRestrictionTypes( $exists = true ) {
2191                 global $wgRestrictionTypes;
2192                 $types = $wgRestrictionTypes;
2193                 if ( $exists ) {
2194                         # Remove the create restriction for existing titles
2195                         $types = array_diff( $types, array( 'create' ) );
2196                 } else {
2197                         # Only the create and upload restrictions apply to non-existing titles
2198                         $types = array_intersect( $types, array( 'create', 'upload' ) );
2199                 }
2200                 return $types;
2201         }
2202
2203         /**
2204          * Returns restriction types for the current Title
2205          *
2206          * @return array applicable restriction types
2207          */
2208         public function getRestrictionTypes() {
2209                 if ( $this->isSpecialPage() ) {
2210                         return array();
2211                 }
2212
2213                 $types = self::getFilteredRestrictionTypes( $this->exists() );
2214
2215                 if ( $this->getNamespace() != NS_FILE ) {
2216                         # Remove the upload restriction for non-file titles
2217                         $types = array_diff( $types, array( 'upload' ) );
2218                 }
2219
2220                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
2221
2222                 wfDebug( __METHOD__ . ': applicable restrictions to [[' .
2223                         $this->getPrefixedText() . ']] are {' . implode( ',', $types ) . "}\n" );
2224
2225                 return $types;
2226         }
2227
2228         /**
2229          * Is this title subject to title protection?
2230          * Title protection is the one applied against creation of such title.
2231          *
2232          * @return Mixed An associative array representing any existent title
2233          *   protection, or false if there's none.
2234          */
2235         private function getTitleProtection() {
2236                 // Can't protect pages in special namespaces
2237                 if ( $this->getNamespace() < 0 ) {
2238                         return false;
2239                 }
2240
2241                 // Can't protect pages that exist.
2242                 if ( $this->exists() ) {
2243                         return false;
2244                 }
2245
2246                 if ( !isset( $this->mTitleProtection ) ) {
2247                         $dbr = wfGetDB( DB_SLAVE );
2248                         $res = $dbr->select( 'protected_titles', '*',
2249                                 array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2250                                 __METHOD__ );
2251
2252                         // fetchRow returns false if there are no rows.
2253                         $this->mTitleProtection = $dbr->fetchRow( $res );
2254                 }
2255                 return $this->mTitleProtection;
2256         }
2257
2258         /**
2259          * Update the title protection status
2260          *
2261          * @deprecated in 1.19; will be removed in 1.20. Use WikiPage::doUpdateRestrictions() instead.
2262          * @param $create_perm String Permission required for creation
2263          * @param $reason String Reason for protection
2264          * @param $expiry String Expiry timestamp
2265          * @return boolean true
2266          */
2267         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
2268                 wfDeprecated( __METHOD__, '1.19' );
2269
2270                 global $wgUser;
2271
2272                 $limit = array( 'create' => $create_perm );
2273                 $expiry = array( 'create' => $expiry );
2274
2275                 $page = WikiPage::factory( $this );
2276                 $status = $page->doUpdateRestrictions( $limit, $expiry, false, $reason, $wgUser );
2277
2278                 return $status->isOK();
2279         }
2280
2281         /**
2282          * Remove any title protection due to page existing
2283          */
2284         public function deleteTitleProtection() {
2285                 $dbw = wfGetDB( DB_MASTER );
2286
2287                 $dbw->delete(
2288                         'protected_titles',
2289                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2290                         __METHOD__
2291                 );
2292                 $this->mTitleProtection = false;
2293         }
2294
2295         /**
2296          * Is this page "semi-protected" - the *only* protection is autoconfirm?
2297          *
2298          * @param $action String Action to check (default: edit)
2299          * @return Bool
2300          */
2301         public function isSemiProtected( $action = 'edit' ) {
2302                 if ( $this->exists() ) {
2303                         $restrictions = $this->getRestrictions( $action );
2304                         if ( count( $restrictions ) > 0 ) {
2305                                 foreach ( $restrictions as $restriction ) {
2306                                         if ( strtolower( $restriction ) != 'autoconfirmed' ) {
2307                                                 return false;
2308                                         }
2309                                 }
2310                         } else {
2311                                 # Not protected
2312                                 return false;
2313                         }
2314                         return true;
2315                 } else {
2316                         # If it doesn't exist, it can't be protected
2317                         return false;
2318                 }
2319         }
2320
2321         /**
2322          * Does the title correspond to a protected article?
2323          *
2324          * @param $action String the action the page is protected from,
2325          * by default checks all actions.
2326          * @return Bool
2327          */
2328         public function isProtected( $action = '' ) {
2329                 global $wgRestrictionLevels;
2330
2331                 $restrictionTypes = $this->getRestrictionTypes();
2332
2333                 # Special pages have inherent protection
2334                 if( $this->isSpecialPage() ) {
2335                         return true;
2336                 }
2337
2338                 # Check regular protection levels
2339                 foreach ( $restrictionTypes as $type ) {
2340                         if ( $action == $type || $action == '' ) {
2341                                 $r = $this->getRestrictions( $type );
2342                                 foreach ( $wgRestrictionLevels as $level ) {
2343                                         if ( in_array( $level, $r ) && $level != '' ) {
2344                                                 return true;
2345                                         }
2346                                 }
2347                         }
2348                 }
2349
2350                 return false;
2351         }
2352
2353         /**
2354          * Determines if $user is unable to edit this page because it has been protected
2355          * by $wgNamespaceProtection.
2356          *
2357          * @param $user User object to check permissions
2358          * @return Bool
2359          */
2360         public function isNamespaceProtected( User $user ) {
2361                 global $wgNamespaceProtection;
2362
2363                 if ( isset( $wgNamespaceProtection[$this->mNamespace] ) ) {
2364                         foreach ( (array)$wgNamespaceProtection[$this->mNamespace] as $right ) {
2365                                 if ( $right != '' && !$user->isAllowed( $right ) ) {
2366                                         return true;
2367                                 }
2368                         }
2369                 }
2370                 return false;
2371         }
2372
2373         /**
2374          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
2375          *
2376          * @return Bool If the page is subject to cascading restrictions.
2377          */
2378         public function isCascadeProtected() {
2379                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
2380                 return ( $sources > 0 );
2381         }
2382
2383         /**
2384          * Cascading protection: Get the source of any cascading restrictions on this page.
2385          *
2386          * @param $getPages Bool Whether or not to retrieve the actual pages
2387          *        that the restrictions have come from.
2388          * @return Mixed Array of Title objects of the pages from which cascading restrictions
2389          *     have come, false for none, or true if such restrictions exist, but $getPages
2390          *     was not set.  The restriction array is an array of each type, each of which
2391          *     contains a array of unique groups.
2392          */
2393         public function getCascadeProtectionSources( $getPages = true ) {
2394                 global $wgContLang;
2395                 $pagerestrictions = array();
2396
2397                 if ( isset( $this->mCascadeSources ) && $getPages ) {
2398                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
2399                 } elseif ( isset( $this->mHasCascadingRestrictions ) && !$getPages ) {
2400                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
2401                 }
2402
2403                 wfProfileIn( __METHOD__ );
2404
2405                 $dbr = wfGetDB( DB_SLAVE );
2406
2407                 if ( $this->getNamespace() == NS_FILE ) {
2408                         $tables = array( 'imagelinks', 'page_restrictions' );
2409                         $where_clauses = array(
2410                                 'il_to' => $this->getDBkey(),
2411                                 'il_from=pr_page',
2412                                 'pr_cascade' => 1
2413                         );
2414                 } else {
2415                         $tables = array( 'templatelinks', 'page_restrictions' );
2416                         $where_clauses = array(
2417                                 'tl_namespace' => $this->getNamespace(),
2418                                 'tl_title' => $this->getDBkey(),
2419                                 'tl_from=pr_page',
2420                                 'pr_cascade' => 1
2421                         );
2422                 }
2423
2424                 if ( $getPages ) {
2425                         $cols = array( 'pr_page', 'page_namespace', 'page_title',
2426                                                    'pr_expiry', 'pr_type', 'pr_level' );
2427                         $where_clauses[] = 'page_id=pr_page';
2428                         $tables[] = 'page';
2429                 } else {
2430                         $cols = array( 'pr_expiry' );
2431                 }
2432
2433                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
2434
2435                 $sources = $getPages ? array() : false;
2436                 $now = wfTimestampNow();
2437                 $purgeExpired = false;
2438
2439                 foreach ( $res as $row ) {
2440                         $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2441                         if ( $expiry > $now ) {
2442                                 if ( $getPages ) {
2443                                         $page_id = $row->pr_page;
2444                                         $page_ns = $row->page_namespace;
2445                                         $page_title = $row->page_title;
2446                                         $sources[$page_id] = Title::makeTitle( $page_ns, $page_title );
2447                                         # Add groups needed for each restriction type if its not already there
2448                                         # Make sure this restriction type still exists
2449
2450                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
2451                                                 $pagerestrictions[$row->pr_type] = array();
2452                                         }
2453
2454                                         if ( isset( $pagerestrictions[$row->pr_type] ) &&
2455                                                  !in_array( $row->pr_level, $pagerestrictions[$row->pr_type] ) ) {
2456                                                 $pagerestrictions[$row->pr_type][] = $row->pr_level;
2457                                         }
2458                                 } else {
2459                                         $sources = true;
2460                                 }
2461                         } else {
2462                                 // Trigger lazy purge of expired restrictions from the db
2463                                 $purgeExpired = true;
2464                         }
2465                 }
2466                 if ( $purgeExpired ) {
2467                         Title::purgeExpiredRestrictions();
2468                 }
2469
2470                 if ( $getPages ) {
2471                         $this->mCascadeSources = $sources;
2472                         $this->mCascadingRestrictions = $pagerestrictions;
2473                 } else {
2474                         $this->mHasCascadingRestrictions = $sources;
2475                 }
2476
2477                 wfProfileOut( __METHOD__ );
2478                 return array( $sources, $pagerestrictions );
2479         }
2480
2481         /**
2482          * Accessor/initialisation for mRestrictions
2483          *
2484          * @param $action String action that permission needs to be checked for
2485          * @return Array of Strings the array of groups allowed to edit this article
2486          */
2487         public function getRestrictions( $action ) {
2488                 if ( !$this->mRestrictionsLoaded ) {
2489                         $this->loadRestrictions();
2490                 }
2491                 return isset( $this->mRestrictions[$action] )
2492                                 ? $this->mRestrictions[$action]
2493                                 : array();
2494         }
2495
2496         /**
2497          * Get the expiry time for the restriction against a given action
2498          *
2499          * @param $action
2500          * @return String|Bool 14-char timestamp, or 'infinity' if the page is protected forever
2501          *     or not protected at all, or false if the action is not recognised.
2502          */
2503         public function getRestrictionExpiry( $action ) {
2504                 if ( !$this->mRestrictionsLoaded ) {
2505                         $this->loadRestrictions();
2506                 }
2507                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2508         }
2509
2510         /**
2511          * Returns cascading restrictions for the current article
2512          *
2513          * @return Boolean
2514          */
2515         function areRestrictionsCascading() {
2516                 if ( !$this->mRestrictionsLoaded ) {
2517                         $this->loadRestrictions();
2518                 }
2519
2520                 return $this->mCascadeRestriction;
2521         }
2522
2523         /**
2524          * Loads a string into mRestrictions array
2525          *
2526          * @param $res Resource restrictions as an SQL result.
2527          * @param $oldFashionedRestrictions String comma-separated list of page
2528          *        restrictions from page table (pre 1.10)
2529          */
2530         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
2531                 $rows = array();
2532
2533                 foreach ( $res as $row ) {
2534                         $rows[] = $row;
2535                 }
2536
2537                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
2538         }
2539
2540         /**
2541          * Compiles list of active page restrictions from both page table (pre 1.10)
2542          * and page_restrictions table for this existing page.
2543          * Public for usage by LiquidThreads.
2544          *
2545          * @param $rows array of db result objects
2546          * @param $oldFashionedRestrictions string comma-separated list of page
2547          *        restrictions from page table (pre 1.10)
2548          */
2549         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
2550                 global $wgContLang;
2551                 $dbr = wfGetDB( DB_SLAVE );
2552
2553                 $restrictionTypes = $this->getRestrictionTypes();
2554
2555                 foreach ( $restrictionTypes as $type ) {
2556                         $this->mRestrictions[$type] = array();
2557                         $this->mRestrictionsExpiry[$type] = $wgContLang->formatExpiry( '', TS_MW );
2558                 }
2559
2560                 $this->mCascadeRestriction = false;
2561
2562                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2563
2564                 if ( $oldFashionedRestrictions === null ) {
2565                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2566                                 array( 'page_id' => $this->getArticleID() ), __METHOD__ );
2567                 }
2568
2569                 if ( $oldFashionedRestrictions != '' ) {
2570
2571                         foreach ( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2572                                 $temp = explode( '=', trim( $restrict ) );
2573                                 if ( count( $temp ) == 1 ) {
2574                                         // old old format should be treated as edit/move restriction
2575                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2576                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2577                                 } else {
2578                                         $restriction = trim( $temp[1] );
2579                                         if( $restriction != '' ) { //some old entries are empty
2580                                                 $this->mRestrictions[$temp[0]] = explode( ',', $restriction );
2581                                         }
2582                                 }
2583                         }
2584
2585                         $this->mOldRestrictions = true;
2586
2587                 }
2588
2589                 if ( count( $rows ) ) {
2590                         # Current system - load second to make them override.
2591                         $now = wfTimestampNow();
2592                         $purgeExpired = false;
2593
2594                         # Cycle through all the restrictions.
2595                         foreach ( $rows as $row ) {
2596
2597                                 // Don't take care of restrictions types that aren't allowed
2598                                 if ( !in_array( $row->pr_type, $restrictionTypes ) )
2599                                         continue;
2600
2601                                 // This code should be refactored, now that it's being used more generally,
2602                                 // But I don't really see any harm in leaving it in Block for now -werdna
2603                                 $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2604
2605                                 // Only apply the restrictions if they haven't expired!
2606                                 if ( !$expiry || $expiry > $now ) {
2607                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2608                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2609
2610                                         $this->mCascadeRestriction |= $row->pr_cascade;
2611                                 } else {
2612                                         // Trigger a lazy purge of expired restrictions
2613                                         $purgeExpired = true;
2614                                 }
2615                         }
2616
2617                         if ( $purgeExpired ) {
2618                                 Title::purgeExpiredRestrictions();
2619                         }
2620                 }
2621
2622                 $this->mRestrictionsLoaded = true;
2623         }
2624
2625         /**
2626          * Load restrictions from the page_restrictions table
2627          *
2628          * @param $oldFashionedRestrictions String comma-separated list of page
2629          *        restrictions from page table (pre 1.10)
2630          */
2631         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2632                 global $wgContLang;
2633                 if ( !$this->mRestrictionsLoaded ) {
2634                         if ( $this->exists() ) {
2635                                 $dbr = wfGetDB( DB_SLAVE );
2636
2637                                 $res = $dbr->select(
2638                                         'page_restrictions',
2639                                         '*',
2640                                         array( 'pr_page' => $this->getArticleID() ),
2641                                         __METHOD__
2642                                 );
2643
2644                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2645                         } else {
2646                                 $title_protection = $this->getTitleProtection();
2647
2648                                 if ( $title_protection ) {
2649                                         $now = wfTimestampNow();
2650                                         $expiry = $wgContLang->formatExpiry( $title_protection['pt_expiry'], TS_MW );
2651
2652                                         if ( !$expiry || $expiry > $now ) {
2653                                                 // Apply the restrictions
2654                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2655                                                 $this->mRestrictions['create'] = explode( ',', trim( $title_protection['pt_create_perm'] ) );
2656                                         } else { // Get rid of the old restrictions
2657                                                 Title::purgeExpiredRestrictions();
2658                                                 $this->mTitleProtection = false;
2659                                         }
2660                                 } else {
2661                                         $this->mRestrictionsExpiry['create'] = $wgContLang->formatExpiry( '', TS_MW );
2662                                 }
2663                                 $this->mRestrictionsLoaded = true;
2664                         }
2665                 }
2666         }
2667
2668         /**
2669          * Flush the protection cache in this object and force reload from the database.
2670          * This is used when updating protection from WikiPage::doUpdateRestrictions().
2671          */
2672         public function flushRestrictions() {
2673                 $this->mRestrictionsLoaded = false;
2674                 $this->mTitleProtection = null;
2675         }
2676
2677         /**
2678          * Purge expired restrictions from the page_restrictions table
2679          */
2680         static function purgeExpiredRestrictions() {
2681                 $dbw = wfGetDB( DB_MASTER );
2682                 $dbw->delete(
2683                         'page_restrictions',
2684                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2685                         __METHOD__
2686                 );
2687
2688                 $dbw->delete(
2689                         'protected_titles',
2690                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2691                         __METHOD__
2692                 );
2693         }
2694
2695         /**
2696          * Does this have subpages?  (Warning, usually requires an extra DB query.)
2697          *
2698          * @return Bool
2699          */
2700         public function hasSubpages() {
2701                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
2702                         # Duh
2703                         return false;
2704                 }
2705
2706                 # We dynamically add a member variable for the purpose of this method
2707                 # alone to cache the result.  There's no point in having it hanging
2708                 # around uninitialized in every Title object; therefore we only add it
2709                 # if needed and don't declare it statically.
2710                 if ( isset( $this->mHasSubpages ) ) {
2711                         return $this->mHasSubpages;
2712                 }
2713
2714                 $subpages = $this->getSubpages( 1 );
2715                 if ( $subpages instanceof TitleArray ) {
2716                         return $this->mHasSubpages = (bool)$subpages->count();
2717                 }
2718                 return $this->mHasSubpages = false;
2719         }
2720
2721         /**
2722          * Get all subpages of this page.
2723          *
2724          * @param $limit Int maximum number of subpages to fetch; -1 for no limit
2725          * @return mixed TitleArray, or empty array if this page's namespace
2726          *  doesn't allow subpages
2727          */
2728         public function getSubpages( $limit = -1 ) {
2729                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
2730                         return array();
2731                 }
2732
2733                 $dbr = wfGetDB( DB_SLAVE );
2734                 $conds['page_namespace'] = $this->getNamespace();
2735                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
2736                 $options = array();
2737                 if ( $limit > -1 ) {
2738                         $options['LIMIT'] = $limit;
2739                 }
2740                 return $this->mSubpages = TitleArray::newFromResult(
2741                         $dbr->select( 'page',
2742                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
2743                                 $conds,
2744                                 __METHOD__,
2745                                 $options
2746                         )
2747                 );
2748         }
2749
2750         /**
2751          * Is there a version of this page in the deletion archive?
2752          *
2753          * @return Int the number of archived revisions
2754          */
2755         public function isDeleted() {
2756                 if ( $this->getNamespace() < 0 ) {
2757                         $n = 0;
2758                 } else {
2759                         $dbr = wfGetDB( DB_SLAVE );
2760
2761                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2762                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2763                                 __METHOD__
2764                         );
2765                         if ( $this->getNamespace() == NS_FILE ) {
2766                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2767                                         array( 'fa_name' => $this->getDBkey() ),
2768                                         __METHOD__
2769                                 );
2770                         }
2771                 }
2772                 return (int)$n;
2773         }
2774
2775         /**
2776          * Is there a version of this page in the deletion archive?
2777          *
2778          * @return Boolean
2779          */
2780         public function isDeletedQuick() {
2781                 if ( $this->getNamespace() < 0 ) {
2782                         return false;
2783                 }
2784                 $dbr = wfGetDB( DB_SLAVE );
2785                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2786                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2787                         __METHOD__
2788                 );
2789                 if ( !$deleted && $this->getNamespace() == NS_FILE ) {
2790                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2791                                 array( 'fa_name' => $this->getDBkey() ),
2792                                 __METHOD__
2793                         );
2794                 }
2795                 return $deleted;
2796         }
2797
2798         /**
2799          * Get the article ID for this Title from the link cache,
2800          * adding it if necessary
2801          *
2802          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select
2803          *  for update
2804          * @return Int the ID
2805          */
2806         public function getArticleID( $flags = 0 ) {
2807                 if ( $this->getNamespace() < 0 ) {
2808                         return $this->mArticleID = 0;
2809                 }
2810                 $linkCache = LinkCache::singleton();
2811                 if ( $flags & self::GAID_FOR_UPDATE ) {
2812                         $oldUpdate = $linkCache->forUpdate( true );
2813                         $linkCache->clearLink( $this );
2814                         $this->mArticleID = $linkCache->addLinkObj( $this );
2815                         $linkCache->forUpdate( $oldUpdate );
2816                 } else {
2817                         if ( -1 == $this->mArticleID ) {
2818                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2819                         }
2820                 }
2821                 return $this->mArticleID;
2822         }
2823
2824         /**
2825          * Is this an article that is a redirect page?
2826          * Uses link cache, adding it if necessary
2827          *
2828          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2829          * @return Bool
2830          */
2831         public function isRedirect( $flags = 0 ) {
2832                 if ( !is_null( $this->mRedirect ) ) {
2833                         return $this->mRedirect;
2834                 }
2835                 # Calling getArticleID() loads the field from cache as needed
2836                 if ( !$this->getArticleID( $flags ) ) {
2837                         return $this->mRedirect = false;
2838                 }
2839
2840                 $linkCache = LinkCache::singleton();
2841                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2842                 if ( $cached === null ) { # check the assumption that the cache actually knows about this title
2843                         # XXX: this does apparently happen, see https://bugzilla.wikimedia.org/show_bug.cgi?id=37209
2844                         #      as a stop gap, perhaps log this, but don't throw an exception?
2845                         throw new MWException( "LinkCache doesn't currently know about this title: " . $this->getPrefixedDBkey() );
2846                 }
2847
2848                 $this->mRedirect = (bool)$cached;
2849
2850                 return $this->mRedirect;
2851         }
2852
2853         /**
2854          * What is the length of this page?
2855          * Uses link cache, adding it if necessary
2856          *
2857          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2858          * @return Int
2859          */
2860         public function getLength( $flags = 0 ) {
2861                 if ( $this->mLength != -1 ) {
2862                         return $this->mLength;
2863                 }
2864                 # Calling getArticleID() loads the field from cache as needed
2865                 if ( !$this->getArticleID( $flags ) ) {
2866                         return $this->mLength = 0;
2867                 }
2868                 $linkCache = LinkCache::singleton();
2869                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'length' );
2870                 if ( $cached === null ) { # check the assumption that the cache actually knows about this title
2871                         # XXX: this does apparently happen, see https://bugzilla.wikimedia.org/show_bug.cgi?id=37209
2872                         #      as a stop gap, perhaps log this, but don't throw an exception?
2873                         throw new MWException( "LinkCache doesn't currently know about this title: " . $this->getPrefixedDBkey() );
2874                 }
2875
2876                 $this->mLength = intval( $cached );
2877
2878                 return $this->mLength;
2879         }
2880
2881         /**
2882          * What is the page_latest field for this page?
2883          *
2884          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2885          * @return Int or 0 if the page doesn't exist
2886          */
2887         public function getLatestRevID( $flags = 0 ) {
2888                 if ( !( $flags & Title::GAID_FOR_UPDATE ) && $this->mLatestID !== false ) {
2889                         return intval( $this->mLatestID );
2890                 }
2891                 # Calling getArticleID() loads the field from cache as needed
2892                 if ( !$this->getArticleID( $flags ) ) {
2893                         return $this->mLatestID = 0;
2894                 }
2895                 $linkCache = LinkCache::singleton();
2896                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'revision' );
2897                 if ( $cached === null ) { # check the assumption that the cache actually knows about this title
2898                         # XXX: this does apparently happen, see https://bugzilla.wikimedia.org/show_bug.cgi?id=37209
2899                         #      as a stop gap, perhaps log this, but don't throw an exception?
2900                         throw new MWException( "LinkCache doesn't currently know about this title: " . $this->getPrefixedDBkey() );
2901                 }
2902
2903                 $this->mLatestID = intval( $cached );
2904
2905                 return $this->mLatestID;
2906         }
2907
2908         /**
2909          * This clears some fields in this object, and clears any associated
2910          * keys in the "bad links" section of the link cache.
2911          *
2912          * - This is called from WikiPage::doEdit() and WikiPage::insertOn() to allow
2913          * loading of the new page_id. It's also called from
2914          * WikiPage::doDeleteArticleReal()
2915          *
2916          * @param $newid Int the new Article ID
2917          */
2918         public function resetArticleID( $newid ) {
2919                 $linkCache = LinkCache::singleton();
2920                 $linkCache->clearLink( $this );
2921
2922                 if ( $newid === false ) {
2923                         $this->mArticleID = -1;
2924                 } else {
2925                         $this->mArticleID = intval( $newid );
2926                 }
2927                 $this->mRestrictionsLoaded = false;
2928                 $this->mRestrictions = array();
2929                 $this->mRedirect = null;
2930                 $this->mLength = -1;
2931                 $this->mLatestID = false;
2932                 $this->mContentModel = false;
2933                 $this->mEstimateRevisions = null;
2934         }
2935
2936         /**
2937          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
2938          *
2939          * @param $text String containing title to capitalize
2940          * @param $ns int namespace index, defaults to NS_MAIN
2941          * @return String containing capitalized title
2942          */
2943         public static function capitalize( $text, $ns = NS_MAIN ) {
2944                 global $wgContLang;
2945
2946                 if ( MWNamespace::isCapitalized( $ns ) ) {
2947                         return $wgContLang->ucfirst( $text );
2948                 } else {
2949                         return $text;
2950                 }
2951         }
2952
2953         /**
2954          * Secure and split - main initialisation function for this object
2955          *
2956          * Assumes that mDbkeyform has been set, and is urldecoded
2957          * and uses underscores, but not otherwise munged.  This function
2958          * removes illegal characters, splits off the interwiki and
2959          * namespace prefixes, sets the other forms, and canonicalizes
2960          * everything.
2961          *
2962          * @return Bool true on success
2963          */
2964         private function secureAndSplit() {
2965                 global $wgContLang, $wgLocalInterwiki;
2966
2967                 # Initialisation
2968                 $this->mInterwiki = $this->mFragment = '';
2969                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2970
2971                 $dbkey = $this->mDbkeyform;
2972
2973                 # Strip Unicode bidi override characters.
2974                 # Sometimes they slip into cut-n-pasted page titles, where the
2975                 # override chars get included in list displays.
2976                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
2977
2978                 # Clean up whitespace
2979                 # Note: use of the /u option on preg_replace here will cause
2980                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
2981                 # conveniently disabling them.
2982                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
2983                 $dbkey = trim( $dbkey, '_' );
2984
2985                 if ( $dbkey == '' ) {
2986                         return false;
2987                 }
2988
2989                 if ( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2990                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2991                         return false;
2992                 }
2993
2994                 $this->mDbkeyform = $dbkey;
2995
2996                 # Initial colon indicates main namespace rather than specified default
2997                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
2998                 if ( ':' == $dbkey[0] ) {
2999                         $this->mNamespace = NS_MAIN;
3000                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
3001                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
3002                 }
3003
3004                 # Namespace or interwiki prefix
3005                 $firstPass = true;
3006                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
3007                 do {
3008                         $m = array();
3009                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
3010                                 $p = $m[1];
3011                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
3012                                         # Ordinary namespace
3013                                         $dbkey = $m[2];
3014                                         $this->mNamespace = $ns;
3015                                         # For Talk:X pages, check if X has a "namespace" prefix
3016                                         if ( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
3017                                                 if ( $wgContLang->getNsIndex( $x[1] ) ) {
3018                                                         # Disallow Talk:File:x type titles...
3019                                                         return false;
3020                                                 } elseif ( Interwiki::isValidInterwiki( $x[1] ) ) {
3021                                                         # Disallow Talk:Interwiki:x type titles...
3022                                                         return false;
3023                                                 }
3024                                         }
3025                                 } elseif ( Interwiki::isValidInterwiki( $p ) ) {
3026                                         if ( !$firstPass ) {
3027                                                 # Can't make a local interwiki link to an interwiki link.
3028                                                 # That's just crazy!
3029                                                 return false;
3030                                         }
3031
3032                                         # Interwiki link
3033                                         $dbkey = $m[2];
3034                                         $this->mInterwiki = $wgContLang->lc( $p );
3035
3036                                         # Redundant interwiki prefix to the local wiki
3037                                         if ( $wgLocalInterwiki !== false
3038                                                 && 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) )
3039                                         {
3040                                                 if ( $dbkey == '' ) {
3041                                                         # Can't have an empty self-link
3042                                                         return false;
3043                                                 }
3044                                                 $this->mInterwiki = '';
3045                                                 $firstPass = false;
3046                                                 # Do another namespace split...
3047                                                 continue;
3048                                         }
3049
3050                                         # If there's an initial colon after the interwiki, that also
3051                                         # resets the default namespace
3052                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
3053                                                 $this->mNamespace = NS_MAIN;
3054                                                 $dbkey = substr( $dbkey, 1 );
3055                                         }
3056                                 }
3057                                 # If there's no recognized interwiki or namespace,
3058                                 # then let the colon expression be part of the title.
3059                         }
3060                         break;
3061                 } while ( true );
3062
3063                 # We already know that some pages won't be in the database!
3064                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
3065                         $this->mArticleID = 0;
3066                 }
3067                 $fragment = strstr( $dbkey, '#' );
3068                 if ( false !== $fragment ) {
3069                         $this->setFragment( $fragment );
3070                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
3071                         # remove whitespace again: prevents "Foo_bar_#"
3072                         # becoming "Foo_bar_"
3073                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
3074                 }
3075
3076                 # Reject illegal characters.
3077                 $rxTc = self::getTitleInvalidRegex();
3078                 if ( preg_match( $rxTc, $dbkey ) ) {
3079                         return false;
3080                 }
3081
3082                 # Pages with "/./" or "/../" appearing in the URLs will often be un-
3083                 # reachable due to the way web browsers deal with 'relative' URLs.
3084                 # Also, they conflict with subpage syntax.  Forbid them explicitly.
3085                 if ( strpos( $dbkey, '.' ) !== false &&
3086                          ( $dbkey === '.' || $dbkey === '..' ||
3087                            strpos( $dbkey, './' ) === 0  ||
3088                            strpos( $dbkey, '../' ) === 0 ||
3089                            strpos( $dbkey, '/./' ) !== false ||
3090                            strpos( $dbkey, '/../' ) !== false  ||
3091                            substr( $dbkey, -2 ) == '/.' ||
3092                            substr( $dbkey, -3 ) == '/..' ) )
3093                 {
3094                         return false;
3095                 }
3096
3097                 # Magic tilde sequences? Nu-uh!
3098                 if ( strpos( $dbkey, '~~~' ) !== false ) {
3099                         return false;
3100                 }
3101
3102                 # Limit the size of titles to 255 bytes. This is typically the size of the
3103                 # underlying database field. We make an exception for special pages, which
3104                 # don't need to be stored in the database, and may edge over 255 bytes due
3105                 # to subpage syntax for long titles, e.g. [[Special:Block/Long name]]
3106                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
3107                   strlen( $dbkey ) > 512 )
3108                 {
3109                         return false;
3110                 }
3111
3112                 # Normally, all wiki links are forced to have an initial capital letter so [[foo]]
3113                 # and [[Foo]] point to the same place.  Don't force it for interwikis, since the
3114                 # other site might be case-sensitive.
3115                 $this->mUserCaseDBKey = $dbkey;
3116                 if ( $this->mInterwiki == '' ) {
3117                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
3118                 }
3119
3120                 # Can't make a link to a namespace alone... "empty" local links can only be
3121                 # self-links with a fragment identifier.
3122                 if ( $dbkey == '' && $this->mInterwiki == '' && $this->mNamespace != NS_MAIN ) {
3123                         return false;
3124                 }
3125
3126                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
3127                 // IP names are not allowed for accounts, and can only be referring to
3128                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
3129                 // there are numerous ways to present the same IP. Having sp:contribs scan
3130                 // them all is silly and having some show the edits and others not is
3131                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
3132                 $dbkey = ( $this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK )
3133                         ? IP::sanitizeIP( $dbkey )
3134                         : $dbkey;
3135
3136                 // Any remaining initial :s are illegal.
3137                 if ( $dbkey !== '' && ':' == $dbkey[0] ) {
3138                         return false;
3139                 }
3140
3141                 # Fill fields
3142                 $this->mDbkeyform = $dbkey;
3143                 $this->mUrlform = wfUrlencode( $dbkey );
3144
3145                 $this->mTextform = str_replace( '_', ' ', $dbkey );
3146
3147                 return true;
3148         }
3149
3150         /**
3151          * Get an array of Title objects linking to this Title
3152          * Also stores the IDs in the link cache.
3153          *
3154          * WARNING: do not use this function on arbitrary user-supplied titles!
3155          * On heavily-used templates it will max out the memory.
3156          *
3157          * @param $options Array: may be FOR UPDATE
3158          * @param $table String: table name
3159          * @param $prefix String: fields prefix
3160          * @return Array of Title objects linking here
3161          */
3162         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3163                 if ( count( $options ) > 0 ) {
3164                         $db = wfGetDB( DB_MASTER );
3165                 } else {
3166                         $db = wfGetDB( DB_SLAVE );
3167                 }
3168
3169                 $res = $db->select(
3170                         array( 'page', $table ),
3171                         self::getSelectFields(),
3172                         array(
3173                                 "{$prefix}_from=page_id",
3174                                 "{$prefix}_namespace" => $this->getNamespace(),
3175                                 "{$prefix}_title"     => $this->getDBkey() ),
3176                         __METHOD__,
3177                         $options
3178                 );
3179
3180                 $retVal = array();
3181                 if ( $res->numRows() ) {
3182                         $linkCache = LinkCache::singleton();
3183                         foreach ( $res as $row ) {
3184                                 $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title );
3185                                 if ( $titleObj ) {
3186                                         $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3187                                         $retVal[] = $titleObj;
3188                                 }
3189                         }
3190                 }
3191                 return $retVal;
3192         }
3193
3194         /**
3195          * Get an array of Title objects using this Title as a template
3196          * Also stores the IDs in the link cache.
3197          *
3198          * WARNING: do not use this function on arbitrary user-supplied titles!
3199          * On heavily-used templates it will max out the memory.
3200          *
3201          * @param $options Array: may be FOR UPDATE
3202          * @return Array of Title the Title objects linking here
3203          */
3204         public function getTemplateLinksTo( $options = array() ) {
3205                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
3206         }
3207
3208         /**
3209          * Get an array of Title objects linked from this Title
3210          * Also stores the IDs in the link cache.
3211          *
3212          * WARNING: do not use this function on arbitrary user-supplied titles!
3213          * On heavily-used templates it will max out the memory.
3214          *
3215          * @param $options Array: may be FOR UPDATE
3216          * @param $table String: table name
3217          * @param $prefix String: fields prefix
3218          * @return Array of Title objects linking here
3219          */
3220         public function getLinksFrom( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3221                 global $wgContentHandlerUseDB;
3222
3223                 $id = $this->getArticleID();
3224
3225                 # If the page doesn't exist; there can't be any link from this page
3226                 if ( !$id ) {
3227                         return array();
3228                 }
3229
3230                 if ( count( $options ) > 0 ) {
3231                         $db = wfGetDB( DB_MASTER );
3232                 } else {
3233                         $db = wfGetDB( DB_SLAVE );
3234                 }
3235
3236                 $namespaceFiled = "{$prefix}_namespace";
3237                 $titleField = "{$prefix}_title";
3238
3239                 $fields = array( $namespaceFiled, $titleField, 'page_id', 'page_len', 'page_is_redirect', 'page_latest' );
3240                 if ( $wgContentHandlerUseDB ) $fields[] = 'page_content_model';
3241
3242                 $res = $db->select(
3243                         array( $table, 'page' ),
3244                         $fields,
3245                         array( "{$prefix}_from" => $id ),
3246                         __METHOD__,
3247                         $options,
3248                         array( 'page' => array( 'LEFT JOIN', array( "page_namespace=$namespaceFiled", "page_title=$titleField" ) ) )
3249                 );
3250
3251                 $retVal = array();
3252                 if ( $res->numRows() ) {
3253                         $linkCache = LinkCache::singleton();
3254                         foreach ( $res as $row ) {
3255                                 $titleObj = Title::makeTitle( $row->$namespaceFiled, $row->$titleField );
3256                                 if ( $titleObj ) {
3257                                         if ( $row->page_id ) {
3258                                                 $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3259                                         } else {
3260                                                 $linkCache->addBadLinkObj( $titleObj );
3261                                         }
3262                                         $retVal[] = $titleObj;
3263                                 }
3264                         }
3265                 }
3266                 return $retVal;
3267         }
3268
3269         /**
3270          * Get an array of Title objects used on this Title as a template
3271          * Also stores the IDs in the link cache.
3272          *
3273          * WARNING: do not use this function on arbitrary user-supplied titles!
3274          * On heavily-used templates it will max out the memory.
3275          *
3276          * @param $options Array: may be FOR UPDATE
3277          * @return Array of Title the Title objects used here
3278          */
3279         public function getTemplateLinksFrom( $options = array() ) {
3280                 return $this->getLinksFrom( $options, 'templatelinks', 'tl' );
3281         }
3282
3283         /**
3284          * Get an array of Title objects referring to non-existent articles linked from this page
3285          *
3286          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
3287          * @return Array of Title the Title objects
3288          */
3289         public function getBrokenLinksFrom() {
3290                 if ( $this->getArticleID() == 0 ) {
3291                         # All links from article ID 0 are false positives
3292                         return array();
3293                 }
3294
3295                 $dbr = wfGetDB( DB_SLAVE );
3296                 $res = $dbr->select(
3297                         array( 'page', 'pagelinks' ),
3298                         array( 'pl_namespace', 'pl_title' ),
3299                         array(
3300                                 'pl_from' => $this->getArticleID(),
3301                                 'page_namespace IS NULL'
3302                         ),
3303                         __METHOD__, array(),
3304                         array(
3305                                 'page' => array(
3306                                         'LEFT JOIN',
3307                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
3308                                 )
3309                         )
3310                 );
3311
3312                 $retVal = array();
3313                 foreach ( $res as $row ) {
3314                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
3315                 }
3316                 return $retVal;
3317         }
3318
3319
3320         /**
3321          * Get a list of URLs to purge from the Squid cache when this
3322          * page changes
3323          *
3324          * @return Array of String the URLs
3325          */
3326         public function getSquidURLs() {
3327                 $urls = array(
3328                         $this->getInternalURL(),
3329                         $this->getInternalURL( 'action=history' )
3330                 );
3331
3332                 $pageLang = $this->getPageLanguage();
3333                 if ( $pageLang->hasVariants() ) {
3334                         $variants = $pageLang->getVariants();
3335                         foreach ( $variants as $vCode ) {
3336                                 $urls[] = $this->getInternalURL( '', $vCode );
3337                         }
3338                 }
3339
3340                 return $urls;
3341         }
3342
3343         /**
3344          * Purge all applicable Squid URLs
3345          */
3346         public function purgeSquid() {
3347                 global $wgUseSquid;
3348                 if ( $wgUseSquid ) {
3349                         $urls = $this->getSquidURLs();
3350                         $u = new SquidUpdate( $urls );
3351                         $u->doUpdate();
3352                 }
3353         }
3354
3355         /**
3356          * Move this page without authentication
3357          *
3358          * @param $nt Title the new page Title
3359          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3360          */
3361         public function moveNoAuth( &$nt ) {
3362                 return $this->moveTo( $nt, false );
3363         }
3364
3365         /**
3366          * Check whether a given move operation would be valid.
3367          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
3368          *
3369          * @param $nt Title the new title
3370          * @param $auth Bool indicates whether $wgUser's permissions
3371          *  should be checked
3372          * @param $reason String is the log summary of the move, used for spam checking
3373          * @return Mixed True on success, getUserPermissionsErrors()-like array on failure
3374          */
3375         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
3376                 global $wgUser;
3377
3378                 $errors = array();
3379                 if ( !$nt ) {
3380                         // Normally we'd add this to $errors, but we'll get
3381                         // lots of syntax errors if $nt is not an object
3382                         return array( array( 'badtitletext' ) );
3383                 }
3384                 if ( $this->equals( $nt ) ) {
3385                         $errors[] = array( 'selfmove' );
3386                 }
3387                 if ( !$this->isMovable() ) {
3388                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
3389                 }
3390                 if ( $nt->getInterwiki() != '' ) {
3391                         $errors[] = array( 'immobile-target-namespace-iw' );
3392                 }
3393                 if ( !$nt->isMovable() ) {
3394                         $errors[] = array( 'immobile-target-namespace', $nt->getNsText() );
3395                 }
3396
3397                 $oldid = $this->getArticleID();
3398                 $newid = $nt->getArticleID();
3399
3400                 if ( strlen( $nt->getDBkey() ) < 1 ) {
3401                         $errors[] = array( 'articleexists' );
3402                 }
3403                 if ( ( $this->getDBkey() == '' ) ||
3404                          ( !$oldid ) ||
3405                          ( $nt->getDBkey() == '' ) ) {
3406                         $errors[] = array( 'badarticleerror' );
3407                 }
3408
3409                 // Image-specific checks
3410                 if ( $this->getNamespace() == NS_FILE ) {
3411                         $errors = array_merge( $errors, $this->validateFileMoveOperation( $nt ) );
3412                 }
3413
3414                 if ( $nt->getNamespace() == NS_FILE && $this->getNamespace() != NS_FILE ) {
3415                         $errors[] = array( 'nonfile-cannot-move-to-file' );
3416                 }
3417
3418                 if ( $auth ) {
3419                         $errors = wfMergeErrorArrays( $errors,
3420                                 $this->getUserPermissionsErrors( 'move', $wgUser ),
3421                                 $this->getUserPermissionsErrors( 'edit', $wgUser ),
3422                                 $nt->getUserPermissionsErrors( 'move-target', $wgUser ),
3423                                 $nt->getUserPermissionsErrors( 'edit', $wgUser ) );
3424                 }
3425
3426                 $match = EditPage::matchSummarySpamRegex( $reason );
3427                 if ( $match !== false ) {
3428                         // This is kind of lame, won't display nice
3429                         $errors[] = array( 'spamprotectiontext' );
3430                 }
3431
3432                 $err = null;
3433                 if ( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
3434                         $errors[] = array( 'hookaborted', $err );
3435                 }
3436
3437                 # The move is allowed only if (1) the target doesn't exist, or
3438                 # (2) the target is a redirect to the source, and has no history
3439                 # (so we can undo bad moves right after they're done).
3440
3441                 if ( 0 != $newid ) { # Target exists; check for validity
3442                         if ( !$this->isValidMoveTarget( $nt ) ) {
3443                                 $errors[] = array( 'articleexists' );
3444                         }
3445                 } else {
3446                         $tp = $nt->getTitleProtection();
3447                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
3448                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
3449                                 $errors[] = array( 'cantmove-titleprotected' );
3450                         }
3451                 }
3452                 if ( empty( $errors ) ) {
3453                         return true;
3454                 }
3455                 return $errors;
3456         }
3457
3458         /**
3459          * Check if the requested move target is a valid file move target
3460          * @param Title $nt Target title
3461          * @return array List of errors
3462          */
3463         protected function validateFileMoveOperation( $nt ) {
3464                 global $wgUser;
3465
3466                 $errors = array();
3467
3468                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is not allowed until below
3469
3470                 $file = wfLocalFile( $this );
3471                 if ( $file->exists() ) {
3472                         if ( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
3473                                 $errors[] = array( 'imageinvalidfilename' );
3474                         }
3475                         if ( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
3476                                 $errors[] = array( 'imagetypemismatch' );
3477                         }
3478                 }
3479
3480                 if ( $nt->getNamespace() != NS_FILE ) {
3481                         $errors[] = array( 'imagenocrossnamespace' );
3482                         // From here we want to do checks on a file object, so if we can't
3483                         // create one, we must return.
3484                         return $errors;
3485                 }
3486
3487                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is allowed below here
3488
3489                 $destFile = wfLocalFile( $nt );
3490                 if ( !$wgUser->isAllowed( 'reupload-shared' ) && !$destFile->exists() && wfFindFile( $nt ) ) {
3491                         $errors[] = array( 'file-exists-sharedrepo' );
3492                 }
3493
3494                 return $errors;
3495         }
3496
3497         /**
3498          * Move a title to a new location
3499          *
3500          * @param $nt Title the new title
3501          * @param $auth Bool indicates whether $wgUser's permissions
3502          *  should be checked
3503          * @param $reason String the reason for the move
3504          * @param $createRedirect Bool Whether to create a redirect from the old title to the new title.
3505          *  Ignored if the user doesn't have the suppressredirect right.
3506          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3507          */
3508         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
3509                 global $wgUser;
3510                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
3511                 if ( is_array( $err ) ) {
3512                         // Auto-block user's IP if the account was "hard" blocked
3513                         $wgUser->spreadAnyEditBlock();
3514                         return $err;
3515                 }
3516                 // Check suppressredirect permission
3517                 if ( $auth && !$wgUser->isAllowed( 'suppressredirect' ) ) {
3518                         $createRedirect = true;
3519                 }
3520
3521                 // If it is a file, move it first.
3522                 // It is done before all other moving stuff is done because it's hard to revert.
3523                 $dbw = wfGetDB( DB_MASTER );
3524                 if ( $this->getNamespace() == NS_FILE ) {
3525                         $file = wfLocalFile( $this );
3526                         if ( $file->exists() ) {
3527                                 $status = $file->move( $nt );
3528                                 if ( !$status->isOk() ) {
3529                                         return $status->getErrorsArray();
3530                                 }
3531                         }
3532                         // Clear RepoGroup process cache
3533                         RepoGroup::singleton()->clearCache( $this );
3534                         RepoGroup::singleton()->clearCache( $nt ); # clear false negative cache
3535                 }
3536
3537                 $dbw->begin( __METHOD__ ); # If $file was a LocalFile, its transaction would have closed our own.
3538                 $pageid = $this->getArticleID( self::GAID_FOR_UPDATE );
3539                 $protected = $this->isProtected();
3540
3541                 // Do the actual move
3542                 $this->moveToInternal( $nt, $reason, $createRedirect );
3543
3544                 // Refresh the sortkey for this row.  Be careful to avoid resetting
3545                 // cl_timestamp, which may disturb time-based lists on some sites.
3546                 $prefixes = $dbw->select(
3547                         'categorylinks',
3548                         array( 'cl_sortkey_prefix', 'cl_to' ),
3549                         array( 'cl_from' => $pageid ),
3550                         __METHOD__
3551                 );
3552                 foreach ( $prefixes as $prefixRow ) {
3553                         $prefix = $prefixRow->cl_sortkey_prefix;
3554                         $catTo = $prefixRow->cl_to;
3555                         $dbw->update( 'categorylinks',
3556                                 array(
3557                                         'cl_sortkey' => Collation::singleton()->getSortKey(
3558                                                 $nt->getCategorySortkey( $prefix ) ),
3559                                         'cl_timestamp=cl_timestamp' ),
3560                                 array(
3561                                         'cl_from' => $pageid,
3562                                         'cl_to' => $catTo ),
3563                                 __METHOD__
3564                         );
3565                 }
3566
3567                 $redirid = $this->getArticleID();
3568
3569                 if ( $protected ) {
3570                         # Protect the redirect title as the title used to be...
3571                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
3572                                 array(
3573                                         'pr_page'    => $redirid,
3574                                         'pr_type'    => 'pr_type',
3575                                         'pr_level'   => 'pr_level',
3576                                         'pr_cascade' => 'pr_cascade',
3577                                         'pr_user'    => 'pr_user',
3578                                         'pr_expiry'  => 'pr_expiry'
3579                                 ),
3580                                 array( 'pr_page' => $pageid ),
3581                                 __METHOD__,
3582                                 array( 'IGNORE' )
3583                         );
3584                         # Update the protection log
3585                         $log = new LogPage( 'protect' );
3586                         $comment = wfMessage(
3587                                 'prot_1movedto2',
3588                                 $this->getPrefixedText(),
3589                                 $nt->getPrefixedText()
3590                         )->inContentLanguage()->text();
3591                         if ( $reason ) {
3592                                 $comment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
3593                         }
3594                         // @todo FIXME: $params?
3595                         $log->addEntry( 'move_prot', $nt, $comment, array( $this->getPrefixedText() ) );
3596                 }
3597
3598                 # Update watchlists
3599                 $oldnamespace = $this->getNamespace() & ~1;
3600                 $newnamespace = $nt->getNamespace() & ~1;
3601                 $oldtitle = $this->getDBkey();
3602                 $newtitle = $nt->getDBkey();
3603
3604                 if ( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
3605                         WatchedItem::duplicateEntries( $this, $nt );
3606                 }
3607
3608                 $dbw->commit( __METHOD__ );
3609
3610                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3611                 return true;
3612         }
3613
3614         /**
3615          * Move page to a title which is either a redirect to the
3616          * source page or nonexistent
3617          *
3618          * @param $nt Title the page to move to, which should be a redirect or nonexistent
3619          * @param $reason String The reason for the move
3620          * @param $createRedirect Bool Whether to leave a redirect at the old title. Does not check
3621          *   if the user has the suppressredirect right
3622          * @throws MWException
3623          */
3624         private function moveToInternal( &$nt, $reason = '', $createRedirect = true ) {
3625                 global $wgUser, $wgContLang;
3626
3627                 if ( $nt->exists() ) {
3628                         $moveOverRedirect = true;
3629                         $logType = 'move_redir';
3630                 } else {
3631                         $moveOverRedirect = false;
3632                         $logType = 'move';
3633                 }
3634
3635                 $redirectSuppressed = !$createRedirect;
3636
3637                 $logEntry = new ManualLogEntry( 'move', $logType );
3638                 $logEntry->setPerformer( $wgUser );
3639                 $logEntry->setTarget( $this );
3640                 $logEntry->setComment( $reason );
3641                 $logEntry->setParameters( array(
3642                         '4::target' => $nt->getPrefixedText(),
3643                         '5::noredir' => $redirectSuppressed ? '1': '0',
3644                 ) );
3645
3646                 $formatter = LogFormatter::newFromEntry( $logEntry );
3647                 $formatter->setContext( RequestContext::newExtraneousContext( $this ) );
3648                 $comment = $formatter->getPlainActionText();
3649                 if ( $reason ) {
3650                         $comment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
3651                 }
3652                 # Truncate for whole multibyte characters.
3653                 $comment = $wgContLang->truncate( $comment, 255 );
3654
3655                 $oldid = $this->getArticleID();
3656
3657                 $dbw = wfGetDB( DB_MASTER );
3658
3659                 $newpage = WikiPage::factory( $nt );
3660
3661                 if ( $moveOverRedirect ) {
3662                         $newid = $nt->getArticleID();
3663
3664                         # Delete the old redirect. We don't save it to history since
3665                         # by definition if we've got here it's rather uninteresting.
3666                         # We have to remove it so that the next step doesn't trigger
3667                         # a conflict on the unique namespace+title index...
3668                         $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3669
3670                         $newpage->doDeleteUpdates( $newid );
3671                 }
3672
3673                 # Save a null revision in the page's history notifying of the move
3674                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3675                 if ( !is_object( $nullRevision ) ) {
3676                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3677                 }
3678                 $nullRevId = $nullRevision->insertOn( $dbw );
3679
3680                 # Change the name of the target page:
3681                 $dbw->update( 'page',
3682                         /* SET */ array(
3683                                 'page_namespace' => $nt->getNamespace(),
3684                                 'page_title'     => $nt->getDBkey(),
3685                         ),
3686                         /* WHERE */ array( 'page_id' => $oldid ),
3687                         __METHOD__
3688                 );
3689
3690                 $this->resetArticleID( 0 );
3691                 $nt->resetArticleID( $oldid );
3692
3693                 $newpage->updateRevisionOn( $dbw, $nullRevision );
3694
3695                 wfRunHooks( 'NewRevisionFromEditComplete',
3696                         array( $newpage, $nullRevision, $nullRevision->getParentId(), $wgUser ) );
3697
3698                 $newpage->doEditUpdates( $nullRevision, $wgUser, array( 'changed' => false ) );
3699
3700                 if ( !$moveOverRedirect ) {
3701                         WikiPage::onArticleCreate( $nt );
3702                 }
3703
3704                 # Recreate the redirect, this time in the other direction.
3705                 if ( $redirectSuppressed ) {
3706                         WikiPage::onArticleDelete( $this );
3707                 } else {
3708                         $mwRedir = MagicWord::get( 'redirect' );
3709                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3710                         $redirectArticle = WikiPage::factory( $this );
3711                         $newid = $redirectArticle->insertOn( $dbw );
3712                         if ( $newid ) { // sanity
3713                                 $redirectRevision = new Revision( array(
3714                                         'page'    => $newid,
3715                                         'comment' => $comment,
3716                                         'text'    => $redirectText ) );
3717                                 $redirectRevision->insertOn( $dbw );
3718                                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3719
3720                                 wfRunHooks( 'NewRevisionFromEditComplete',
3721                                         array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3722
3723                                 $redirectArticle->doEditUpdates( $redirectRevision, $wgUser, array( 'created' => true ) );
3724                         }
3725                 }
3726
3727                 # Log the move
3728                 $logid = $logEntry->insert();
3729                 $logEntry->publish( $logid );
3730         }
3731
3732         /**
3733          * Move this page's subpages to be subpages of $nt
3734          *
3735          * @param $nt Title Move target
3736          * @param $auth bool Whether $wgUser's permissions should be checked
3737          * @param $reason string The reason for the move
3738          * @param $createRedirect bool Whether to create redirects from the old subpages to
3739          *     the new ones Ignored if the user doesn't have the 'suppressredirect' right
3740          * @return mixed array with old page titles as keys, and strings (new page titles) or
3741          *     arrays (errors) as values, or an error array with numeric indices if no pages
3742          *     were moved
3743          */
3744         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3745                 global $wgMaximumMovedPages;
3746                 // Check permissions
3747                 if ( !$this->userCan( 'move-subpages' ) ) {
3748                         return array( 'cant-move-subpages' );
3749                 }
3750                 // Do the source and target namespaces support subpages?
3751                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
3752                         return array( 'namespace-nosubpages',
3753                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3754                 }
3755                 if ( !MWNamespace::hasSubpages( $nt->getNamespace() ) ) {
3756                         return array( 'namespace-nosubpages',
3757                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3758                 }
3759
3760                 $subpages = $this->getSubpages( $wgMaximumMovedPages + 1 );
3761                 $retval = array();
3762                 $count = 0;
3763                 foreach ( $subpages as $oldSubpage ) {
3764                         $count++;
3765                         if ( $count > $wgMaximumMovedPages ) {
3766                                 $retval[$oldSubpage->getPrefixedTitle()] =
3767                                                 array( 'movepage-max-pages',
3768                                                         $wgMaximumMovedPages );
3769                                 break;
3770                         }
3771
3772                         // We don't know whether this function was called before
3773                         // or after moving the root page, so check both
3774                         // $this and $nt
3775                         if ( $oldSubpage->getArticleID() == $this->getArticleID() ||
3776                                         $oldSubpage->getArticleID() == $nt->getArticleID() )
3777                         {
3778                                 // When moving a page to a subpage of itself,
3779                                 // don't move it twice
3780                                 continue;
3781                         }
3782                         $newPageName = preg_replace(
3783                                         '#^' . preg_quote( $this->getDBkey(), '#' ) . '#',
3784                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3785                                         $oldSubpage->getDBkey() );
3786                         if ( $oldSubpage->isTalkPage() ) {
3787                                 $newNs = $nt->getTalkPage()->getNamespace();
3788                         } else {
3789                                 $newNs = $nt->getSubjectPage()->getNamespace();
3790                         }
3791                         # Bug 14385: we need makeTitleSafe because the new page names may
3792                         # be longer than 255 characters.
3793                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3794
3795                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3796                         if ( $success === true ) {
3797                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3798                         } else {
3799                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3800                         }
3801                 }
3802                 return $retval;
3803         }
3804
3805         /**
3806          * Checks if this page is just a one-rev redirect.
3807          * Adds lock, so don't use just for light purposes.
3808          *
3809          * @return Bool
3810          */
3811         public function isSingleRevRedirect() {
3812                 global $wgContentHandlerUseDB;
3813
3814                 $dbw = wfGetDB( DB_MASTER );
3815
3816                 # Is it a redirect?
3817                 $fields = array( 'page_is_redirect', 'page_latest', 'page_id' );
3818                 if ( $wgContentHandlerUseDB ) $fields[] = 'page_content_model';
3819
3820                 $row = $dbw->selectRow( 'page',
3821                         $fields,
3822                         $this->pageCond(),
3823                         __METHOD__,
3824                         array( 'FOR UPDATE' )
3825                 );
3826                 # Cache some fields we may want
3827                 $this->mArticleID = $row ? intval( $row->page_id ) : 0;
3828                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3829                 $this->mLatestID = $row ? intval( $row->page_latest ) : false;
3830                 $this->mContentModel = $row && isset( $row->page_content_model ) ? strval( $row->page_content_model ) : false;
3831                 if ( !$this->mRedirect ) {
3832                         return false;
3833                 }
3834                 # Does the article have a history?
3835                 $row = $dbw->selectField( array( 'page', 'revision' ),
3836                         'rev_id',
3837                         array( 'page_namespace' => $this->getNamespace(),
3838                                 'page_title' => $this->getDBkey(),
3839                                 'page_id=rev_page',
3840                                 'page_latest != rev_id'
3841                         ),
3842                         __METHOD__,
3843                         array( 'FOR UPDATE' )
3844                 );
3845                 # Return true if there was no history
3846                 return ( $row === false );
3847         }
3848
3849         /**
3850          * Checks if $this can be moved to a given Title
3851          * - Selects for update, so don't call it unless you mean business
3852          *
3853          * @param $nt Title the new title to check
3854          * @return Bool
3855          */
3856         public function isValidMoveTarget( $nt ) {
3857                 # Is it an existing file?
3858                 if ( $nt->getNamespace() == NS_FILE ) {
3859                         $file = wfLocalFile( $nt );
3860                         if ( $file->exists() ) {
3861                                 wfDebug( __METHOD__ . ": file exists\n" );
3862                                 return false;
3863                         }
3864                 }
3865                 # Is it a redirect with no history?
3866                 if ( !$nt->isSingleRevRedirect() ) {
3867                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3868                         return false;
3869                 }
3870                 # Get the article text
3871                 $rev = Revision::newFromTitle( $nt, false, Revision::READ_LATEST );
3872                 if( !is_object( $rev ) ){
3873                         return false;
3874                 }
3875                 $content = $rev->getContent();
3876                 # Does the redirect point to the source?
3877                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3878                 $redirTitle = $content->getRedirectTarget();
3879
3880                 if ( $redirTitle ) {
3881                         if ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3882                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) {
3883                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3884                                 return false;
3885                         } else {
3886                                 return true;
3887                         }
3888                 } else {
3889                         # Fail safe (not a redirect after all. strange.)
3890                         wfDebug( __METHOD__ . ": failsafe: database sais " . $nt->getPrefixedDBkey() .
3891                                                 " is a redirect, but it doesn't contain a valid redirect.\n" );
3892                         return false;
3893                 }
3894         }
3895
3896         /**
3897          * Get categories to which this Title belongs and return an array of
3898          * categories' names.
3899          *
3900          * @return Array of parents in the form:
3901          *        $parent => $currentarticle
3902          */
3903         public function getParentCategories() {
3904                 global $wgContLang;
3905
3906                 $data = array();
3907
3908                 $titleKey = $this->getArticleID();
3909
3910                 if ( $titleKey === 0 ) {
3911                         return $data;
3912                 }
3913
3914                 $dbr = wfGetDB( DB_SLAVE );
3915
3916                 $res = $dbr->select( 'categorylinks', '*',
3917                         array(
3918                                 'cl_from' => $titleKey,
3919                         ),
3920                         __METHOD__,
3921                         array()
3922                 );
3923
3924                 if ( $dbr->numRows( $res ) > 0 ) {
3925                         foreach ( $res as $row ) {
3926                                 // $data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
3927                                 $data[$wgContLang->getNSText( NS_CATEGORY ) . ':' . $row->cl_to] = $this->getFullText();
3928                         }
3929                 }
3930                 return $data;
3931         }
3932
3933         /**
3934          * Get a tree of parent categories
3935          *
3936          * @param $children Array with the children in the keys, to check for circular refs
3937          * @return Array Tree of parent categories
3938          */
3939         public function getParentCategoryTree( $children = array() ) {
3940                 $stack = array();
3941                 $parents = $this->getParentCategories();
3942
3943                 if ( $parents ) {
3944                         foreach ( $parents as $parent => $current ) {
3945                                 if ( array_key_exists( $parent, $children ) ) {
3946                                         # Circular reference
3947                                         $stack[$parent] = array();
3948                                 } else {
3949                                         $nt = Title::newFromText( $parent );
3950                                         if ( $nt ) {
3951                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array( $parent => 1 ) );
3952                                         }
3953                                 }
3954                         }
3955                 }
3956
3957                 return $stack;
3958         }
3959
3960         /**
3961          * Get an associative array for selecting this title from
3962          * the "page" table
3963          *
3964          * @return Array suitable for the $where parameter of DB::select()
3965          */
3966         public function pageCond() {
3967                 if ( $this->mArticleID > 0 ) {
3968                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
3969                         return array( 'page_id' => $this->mArticleID );
3970                 } else {
3971                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
3972                 }
3973         }
3974
3975         /**
3976          * Get the revision ID of the previous revision
3977          *
3978          * @param $revId Int Revision ID. Get the revision that was before this one.
3979          * @param $flags Int Title::GAID_FOR_UPDATE
3980          * @return Int|Bool Old revision ID, or FALSE if none exists
3981          */
3982         public function getPreviousRevisionID( $revId, $flags = 0 ) {
3983                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3984                 $revId = $db->selectField( 'revision', 'rev_id',
3985                         array(
3986                                 'rev_page' => $this->getArticleID( $flags ),
3987                                 'rev_id < ' . intval( $revId )
3988                         ),
3989                         __METHOD__,
3990                         array( 'ORDER BY' => 'rev_id DESC' )
3991                 );
3992
3993                 if ( $revId === false ) {
3994                         return false;
3995                 } else {
3996                         return intval( $revId );
3997                 }
3998         }
3999
4000         /**
4001          * Get the revision ID of the next revision
4002          *
4003          * @param $revId Int Revision ID. Get the revision that was after this one.
4004          * @param $flags Int Title::GAID_FOR_UPDATE
4005          * @return Int|Bool Next revision ID, or FALSE if none exists
4006          */
4007         public function getNextRevisionID( $revId, $flags = 0 ) {
4008                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4009                 $revId = $db->selectField( 'revision', 'rev_id',
4010                         array(
4011                                 'rev_page' => $this->getArticleID( $flags ),
4012                                 'rev_id > ' . intval( $revId )
4013                         ),
4014                         __METHOD__,
4015                         array( 'ORDER BY' => 'rev_id' )
4016                 );
4017
4018                 if ( $revId === false ) {
4019                         return false;
4020                 } else {
4021                         return intval( $revId );
4022                 }
4023         }
4024
4025         /**
4026          * Get the first revision of the page
4027          *
4028          * @param $flags Int Title::GAID_FOR_UPDATE
4029          * @return Revision|Null if page doesn't exist
4030          */
4031         public function getFirstRevision( $flags = 0 ) {
4032                 $pageId = $this->getArticleID( $flags );
4033                 if ( $pageId ) {
4034                         $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4035                         $row = $db->selectRow( 'revision', Revision::selectFields(),
4036                                 array( 'rev_page' => $pageId ),
4037                                 __METHOD__,
4038                                 array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
4039                         );
4040                         if ( $row ) {
4041                                 return new Revision( $row );
4042                         }
4043                 }
4044                 return null;
4045         }
4046
4047         /**
4048          * Get the oldest revision timestamp of this page
4049          *
4050          * @param $flags Int Title::GAID_FOR_UPDATE
4051          * @return String: MW timestamp
4052          */
4053         public function getEarliestRevTime( $flags = 0 ) {
4054                 $rev = $this->getFirstRevision( $flags );
4055                 return $rev ? $rev->getTimestamp() : null;
4056         }
4057
4058         /**
4059          * Check if this is a new page
4060          *
4061          * @return bool
4062          */
4063         public function isNewPage() {
4064                 $dbr = wfGetDB( DB_SLAVE );
4065                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
4066         }
4067
4068         /**
4069          * Check whether the number of revisions of this page surpasses $wgDeleteRevisionsLimit
4070          *
4071          * @return bool
4072          */
4073         public function isBigDeletion() {
4074                 global $wgDeleteRevisionsLimit;
4075
4076                 if ( !$wgDeleteRevisionsLimit ) {
4077                         return false;
4078                 }
4079
4080                 $revCount = $this->estimateRevisionCount();
4081                 return $revCount > $wgDeleteRevisionsLimit;
4082         }
4083
4084         /**
4085          * Get the  approximate revision count of this page.
4086          *
4087          * @return int
4088          */
4089         public function estimateRevisionCount() {
4090                 if ( !$this->exists() ) {
4091                         return 0;
4092                 }
4093
4094                 if ( $this->mEstimateRevisions === null ) {
4095                         $dbr = wfGetDB( DB_SLAVE );
4096                         $this->mEstimateRevisions = $dbr->estimateRowCount( 'revision', '*',
4097                                 array( 'rev_page' => $this->getArticleID() ), __METHOD__ );
4098                 }
4099
4100                 return $this->mEstimateRevisions;
4101         }
4102
4103         /**
4104          * Get the number of revisions between the given revision.
4105          * Used for diffs and other things that really need it.
4106          *
4107          * @param $old int|Revision Old revision or rev ID (first before range)
4108          * @param $new int|Revision New revision or rev ID (first after range)
4109          * @return Int Number of revisions between these revisions.
4110          */
4111         public function countRevisionsBetween( $old, $new ) {
4112                 if ( !( $old instanceof Revision ) ) {
4113                         $old = Revision::newFromTitle( $this, (int)$old );
4114                 }
4115                 if ( !( $new instanceof Revision ) ) {
4116                         $new = Revision::newFromTitle( $this, (int)$new );
4117                 }
4118                 if ( !$old || !$new ) {
4119                         return 0; // nothing to compare
4120                 }
4121                 $dbr = wfGetDB( DB_SLAVE );
4122                 return (int)$dbr->selectField( 'revision', 'count(*)',
4123                         array(
4124                                 'rev_page' => $this->getArticleID(),
4125                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4126                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4127                         ),
4128                         __METHOD__
4129                 );
4130         }
4131
4132         /**
4133          * Get the number of authors between the given revisions or revision IDs.
4134          * Used for diffs and other things that really need it.
4135          *
4136          * @param $old int|Revision Old revision or rev ID (first before range by default)
4137          * @param $new int|Revision New revision or rev ID (first after range by default)
4138          * @param $limit int Maximum number of authors
4139          * @param $options string|array (Optional): Single option, or an array of options:
4140          *     'include_old' Include $old in the range; $new is excluded.
4141          *     'include_new' Include $new in the range; $old is excluded.
4142          *     'include_both' Include both $old and $new in the range.
4143          *     Unknown option values are ignored.
4144          * @return int Number of revision authors in the range; zero if not both revisions exist
4145          */
4146         public function countAuthorsBetween( $old, $new, $limit, $options = array() ) {
4147                 if ( !( $old instanceof Revision ) ) {
4148                         $old = Revision::newFromTitle( $this, (int)$old );
4149                 }
4150                 if ( !( $new instanceof Revision ) ) {
4151                         $new = Revision::newFromTitle( $this, (int)$new );
4152                 }
4153                 // XXX: what if Revision objects are passed in, but they don't refer to this title?
4154                 // Add $old->getPage() != $new->getPage() || $old->getPage() != $this->getArticleID()
4155                 // in the sanity check below?
4156                 if ( !$old || !$new ) {
4157                         return 0; // nothing to compare
4158                 }
4159                 $old_cmp = '>';
4160                 $new_cmp = '<';
4161                 $options = (array) $options;
4162                 if ( in_array( 'include_old', $options ) ) {
4163                         $old_cmp = '>=';
4164                 }
4165                 if ( in_array( 'include_new', $options ) ) {
4166                         $new_cmp = '<=';
4167                 }
4168                 if ( in_array( 'include_both', $options ) ) {
4169                         $old_cmp = '>=';
4170                         $new_cmp = '<=';
4171                 }
4172                 // No DB query needed if $old and $new are the same or successive revisions:
4173                 if ( $old->getId() === $new->getId() ) {
4174                         return ( $old_cmp === '>' && $new_cmp === '<' ) ? 0 : 1;
4175                 } else if ( $old->getId() === $new->getParentId() ) {
4176                         if ( $old_cmp === '>' || $new_cmp === '<' ) {
4177                                 return ( $old_cmp === '>' && $new_cmp === '<' ) ? 0 : 1;
4178                         }
4179                         return ( $old->getRawUserText() === $new->getRawUserText() ) ? 1 : 2;
4180                 }
4181                 $dbr = wfGetDB( DB_SLAVE );
4182                 $res = $dbr->select( 'revision', 'DISTINCT rev_user_text',
4183                         array(
4184                                 'rev_page' => $this->getArticleID(),
4185                                 "rev_timestamp $old_cmp " . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4186                                 "rev_timestamp $new_cmp " . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4187                         ), __METHOD__,
4188                         array( 'LIMIT' => $limit + 1 ) // add one so caller knows it was truncated
4189                 );
4190                 return (int)$dbr->numRows( $res );
4191         }
4192
4193         /**
4194          * Compare with another title.
4195          *
4196          * @param $title Title
4197          * @return Bool
4198          */
4199         public function equals( Title $title ) {
4200                 // Note: === is necessary for proper matching of number-like titles.
4201                 return $this->getInterwiki() === $title->getInterwiki()
4202                         && $this->getNamespace() == $title->getNamespace()
4203                         && $this->getDBkey() === $title->getDBkey();
4204         }
4205
4206         /**
4207          * Check if this title is a subpage of another title
4208          *
4209          * @param $title Title
4210          * @return Bool
4211          */
4212         public function isSubpageOf( Title $title ) {
4213                 return $this->getInterwiki() === $title->getInterwiki()
4214                         && $this->getNamespace() == $title->getNamespace()
4215                         && strpos( $this->getDBkey(), $title->getDBkey() . '/' ) === 0;
4216         }
4217
4218         /**
4219          * Check if page exists.  For historical reasons, this function simply
4220          * checks for the existence of the title in the page table, and will
4221          * thus return false for interwiki links, special pages and the like.
4222          * If you want to know if a title can be meaningfully viewed, you should
4223          * probably call the isKnown() method instead.
4224          *
4225          * @return Bool
4226          */
4227         public function exists() {
4228                 return $this->getArticleID() != 0;
4229         }
4230
4231         /**
4232          * Should links to this title be shown as potentially viewable (i.e. as
4233          * "bluelinks"), even if there's no record by this title in the page
4234          * table?
4235          *
4236          * This function is semi-deprecated for public use, as well as somewhat
4237          * misleadingly named.  You probably just want to call isKnown(), which
4238          * calls this function internally.
4239          *
4240          * (ISSUE: Most of these checks are cheap, but the file existence check
4241          * can potentially be quite expensive.  Including it here fixes a lot of
4242          * existing code, but we might want to add an optional parameter to skip
4243          * it and any other expensive checks.)
4244          *
4245          * @return Bool
4246          */
4247         public function isAlwaysKnown() {
4248                 $isKnown = null;
4249
4250                 /**
4251                  * Allows overriding default behaviour for determining if a page exists.
4252                  * If $isKnown is kept as null, regular checks happen. If it's
4253                  * a boolean, this value is returned by the isKnown method.
4254                  *
4255                  * @since 1.20
4256                  *
4257                  * @param Title $title
4258                  * @param boolean|null $isKnown
4259                  */
4260                 wfRunHooks( 'TitleIsAlwaysKnown', array( $this, &$isKnown ) );
4261
4262                 if ( !is_null( $isKnown ) ) {
4263                         return $isKnown;
4264                 }
4265
4266                 if ( $this->mInterwiki != '' ) {
4267                         return true;  // any interwiki link might be viewable, for all we know
4268                 }
4269
4270                 switch( $this->mNamespace ) {
4271                         case NS_MEDIA:
4272                         case NS_FILE:
4273                                 // file exists, possibly in a foreign repo
4274                                 return (bool)wfFindFile( $this );
4275                         case NS_SPECIAL:
4276                                 // valid special page
4277                                 return SpecialPageFactory::exists( $this->getDBkey() );
4278                         case NS_MAIN:
4279                                 // selflink, possibly with fragment
4280                                 return $this->mDbkeyform == '';
4281                         case NS_MEDIAWIKI:
4282                                 // known system message
4283                                 return $this->hasSourceText() !== false;
4284                         default:
4285                                 return false;
4286                 }
4287         }
4288
4289         /**
4290          * Does this title refer to a page that can (or might) be meaningfully
4291          * viewed?  In particular, this function may be used to determine if
4292          * links to the title should be rendered as "bluelinks" (as opposed to
4293          * "redlinks" to non-existent pages).
4294          * Adding something else to this function will cause inconsistency
4295          * since LinkHolderArray calls isAlwaysKnown() and does its own
4296          * page existence check.
4297          *
4298          * @return Bool
4299          */
4300         public function isKnown() {
4301                 return $this->isAlwaysKnown() || $this->exists();
4302         }
4303
4304         /**
4305          * Does this page have source text?
4306          *
4307          * @return Boolean
4308          */
4309         public function hasSourceText() {
4310                 if ( $this->exists() ) {
4311                         return true;
4312                 }
4313
4314                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
4315                         // If the page doesn't exist but is a known system message, default
4316                         // message content will be displayed, same for language subpages-
4317                         // Use always content language to avoid loading hundreds of languages
4318                         // to get the link color.
4319                         global $wgContLang;
4320                         list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4321                         $message = wfMessage( $name )->inLanguage( $wgContLang )->useDatabase( false );
4322                         return $message->exists();
4323                 }
4324
4325                 return false;
4326         }
4327
4328         /**
4329          * Get the default message text or false if the message doesn't exist
4330          *
4331          * @return String or false
4332          */
4333         public function getDefaultMessageText() {
4334                 global $wgContLang;
4335
4336                 if ( $this->getNamespace() != NS_MEDIAWIKI ) { // Just in case
4337                         return false;
4338                 }
4339
4340                 list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4341                 $message = wfMessage( $name )->inLanguage( $lang )->useDatabase( false );
4342
4343                 if ( $message->exists() ) {
4344                         return $message->plain();
4345                 } else {
4346                         return false;
4347                 }
4348         }
4349
4350         /**
4351          * Updates page_touched for this page; called from LinksUpdate.php
4352          *
4353          * @return Bool true if the update succeded
4354          */
4355         public function invalidateCache() {
4356                 if ( wfReadOnly() ) {
4357                         return false;
4358                 }
4359                 $dbw = wfGetDB( DB_MASTER );
4360                 $success = $dbw->update(
4361                         'page',
4362                         array( 'page_touched' => $dbw->timestamp() ),
4363                         $this->pageCond(),
4364                         __METHOD__
4365                 );
4366                 HTMLFileCache::clearFileCache( $this );
4367                 return $success;
4368         }
4369
4370         /**
4371          * Update page_touched timestamps and send squid purge messages for
4372          * pages linking to this title. May be sent to the job queue depending
4373          * on the number of links. Typically called on create and delete.
4374          */
4375         public function touchLinks() {
4376                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
4377                 $u->doUpdate();
4378
4379                 if ( $this->getNamespace() == NS_CATEGORY ) {
4380                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
4381                         $u->doUpdate();
4382                 }
4383         }
4384
4385         /**
4386          * Get the last touched timestamp
4387          *
4388          * @param $db DatabaseBase: optional db
4389          * @return String last-touched timestamp
4390          */
4391         public function getTouched( $db = null ) {
4392                 $db = isset( $db ) ? $db : wfGetDB( DB_SLAVE );
4393                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
4394                 return $touched;
4395         }
4396
4397         /**
4398          * Get the timestamp when this page was updated since the user last saw it.
4399          *
4400          * @param $user User
4401          * @return String|Null
4402          */
4403         public function getNotificationTimestamp( $user = null ) {
4404                 global $wgUser, $wgShowUpdatedMarker;
4405                 // Assume current user if none given
4406                 if ( !$user ) {
4407                         $user = $wgUser;
4408                 }
4409                 // Check cache first
4410                 $uid = $user->getId();
4411                 // avoid isset here, as it'll return false for null entries
4412                 if ( array_key_exists( $uid, $this->mNotificationTimestamp ) ) {
4413                         return $this->mNotificationTimestamp[$uid];
4414                 }
4415                 if ( !$uid || !$wgShowUpdatedMarker ) {
4416                         return $this->mNotificationTimestamp[$uid] = false;
4417                 }
4418                 // Don't cache too much!
4419                 if ( count( $this->mNotificationTimestamp ) >= self::CACHE_MAX ) {
4420                         $this->mNotificationTimestamp = array();
4421                 }
4422                 $dbr = wfGetDB( DB_SLAVE );
4423                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
4424                         'wl_notificationtimestamp',
4425                         array(
4426                                 'wl_user' => $user->getId(),
4427                                 'wl_namespace' => $this->getNamespace(),
4428                                 'wl_title' => $this->getDBkey(),
4429                         ),
4430                         __METHOD__
4431                 );
4432                 return $this->mNotificationTimestamp[$uid];
4433         }
4434
4435         /**
4436          * Generate strings used for xml 'id' names in monobook tabs
4437          *
4438          * @param $prepend string defaults to 'nstab-'
4439          * @return String XML 'id' name
4440          */
4441         public function getNamespaceKey( $prepend = 'nstab-' ) {
4442                 global $wgContLang;
4443                 // Gets the subject namespace if this title
4444                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
4445                 // Checks if cononical namespace name exists for namespace
4446                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
4447                         // Uses canonical namespace name
4448                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
4449                 } else {
4450                         // Uses text of namespace
4451                         $namespaceKey = $this->getSubjectNsText();
4452                 }
4453                 // Makes namespace key lowercase
4454                 $namespaceKey = $wgContLang->lc( $namespaceKey );
4455                 // Uses main
4456                 if ( $namespaceKey == '' ) {
4457                         $namespaceKey = 'main';
4458                 }
4459                 // Changes file to image for backwards compatibility
4460                 if ( $namespaceKey == 'file' ) {
4461                         $namespaceKey = 'image';
4462                 }
4463                 return $prepend . $namespaceKey;
4464         }
4465
4466         /**
4467          * Get all extant redirects to this Title
4468          *
4469          * @param $ns Int|Null Single namespace to consider; NULL to consider all namespaces
4470          * @return Array of Title redirects to this title
4471          */
4472         public function getRedirectsHere( $ns = null ) {
4473                 $redirs = array();
4474
4475                 $dbr = wfGetDB( DB_SLAVE );
4476                 $where = array(
4477                         'rd_namespace' => $this->getNamespace(),
4478                         'rd_title' => $this->getDBkey(),
4479                         'rd_from = page_id'
4480                 );
4481                 if ( $this->isExternal() ) {
4482                         $where['rd_interwiki'] = $this->getInterwiki();
4483                 } else {
4484                         $where[] = 'rd_interwiki = ' . $dbr->addQuotes( '' ) . ' OR rd_interwiki IS NULL';
4485                 }
4486                 if ( !is_null( $ns ) ) {
4487                         $where['page_namespace'] = $ns;
4488                 }
4489
4490                 $res = $dbr->select(
4491                         array( 'redirect', 'page' ),
4492                         array( 'page_namespace', 'page_title' ),
4493                         $where,
4494                         __METHOD__
4495                 );
4496
4497                 foreach ( $res as $row ) {
4498                         $redirs[] = self::newFromRow( $row );
4499                 }
4500                 return $redirs;
4501         }
4502
4503         /**
4504          * Check if this Title is a valid redirect target
4505          *
4506          * @return Bool
4507          */
4508         public function isValidRedirectTarget() {
4509                 global $wgInvalidRedirectTargets;
4510
4511                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
4512                 if ( $this->isSpecial( 'Userlogout' ) ) {
4513                         return false;
4514                 }
4515
4516                 foreach ( $wgInvalidRedirectTargets as $target ) {
4517                         if ( $this->isSpecial( $target ) ) {
4518                                 return false;
4519                         }
4520                 }
4521
4522                 return true;
4523         }
4524
4525         /**
4526          * Get a backlink cache object
4527          *
4528          * @return BacklinkCache
4529          */
4530         public function getBacklinkCache() {
4531                 return BacklinkCache::get( $this );
4532         }
4533
4534         /**
4535          * Whether the magic words __INDEX__ and __NOINDEX__ function for  this page.
4536          *
4537          * @return Boolean
4538          */
4539         public function canUseNoindex() {
4540                 global $wgContentNamespaces, $wgExemptFromUserRobotsControl;
4541
4542                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
4543                         ? $wgContentNamespaces
4544                         : $wgExemptFromUserRobotsControl;
4545
4546                 return !in_array( $this->mNamespace, $bannedNamespaces );
4547
4548         }
4549
4550         /**
4551          * Returns the raw sort key to be used for categories, with the specified
4552          * prefix.  This will be fed to Collation::getSortKey() to get a
4553          * binary sortkey that can be used for actual sorting.
4554          *
4555          * @param $prefix string The prefix to be used, specified using
4556          *   {{defaultsort:}} or like [[Category:Foo|prefix]].  Empty for no
4557          *   prefix.
4558          * @return string
4559          */
4560         public function getCategorySortkey( $prefix = '' ) {
4561                 $unprefixed = $this->getText();
4562
4563                 // Anything that uses this hook should only depend
4564                 // on the Title object passed in, and should probably
4565                 // tell the users to run updateCollations.php --force
4566                 // in order to re-sort existing category relations.
4567                 wfRunHooks( 'GetDefaultSortkey', array( $this, &$unprefixed ) );
4568                 if ( $prefix !== '' ) {
4569                         # Separate with a line feed, so the unprefixed part is only used as
4570                         # a tiebreaker when two pages have the exact same prefix.
4571                         # In UCA, tab is the only character that can sort above LF
4572                         # so we strip both of them from the original prefix.
4573                         $prefix = strtr( $prefix, "\n\t", '  ' );
4574                         return "$prefix\n$unprefixed";
4575                 }
4576                 return $unprefixed;
4577         }
4578
4579         /**
4580          * Get the language in which the content of this page is written in
4581          * wikitext. Defaults to $wgContLang, but in certain cases it can be
4582          * e.g. $wgLang (such as special pages, which are in the user language).
4583          *
4584          * @since 1.18
4585          * @return Language
4586          */
4587         public function getPageLanguage() {
4588                 global $wgLang;
4589                 if ( $this->isSpecialPage() ) {
4590                         // special pages are in the user language
4591                         return $wgLang;
4592                 }
4593
4594                 //TODO: use the LinkCache to cache this! Note that this may depend on user settings, so the cache should be only per-request.
4595                 //NOTE: ContentHandler::getPageLanguage() may need to load the content to determine the page language!
4596                 $contentHandler = ContentHandler::getForTitle( $this );
4597                 $pageLang = $contentHandler->getPageLanguage( $this );
4598
4599                 // Hook at the end because we don't want to override the above stuff
4600                 wfRunHooks( 'PageContentLanguage', array( $this, &$pageLang, $wgLang ) );
4601                 return wfGetLangObj( $pageLang );
4602         }
4603
4604         /**
4605          * Get the language in which the content of this page is written when
4606          * viewed by user. Defaults to $wgContLang, but in certain cases it can be
4607          * e.g. $wgLang (such as special pages, which are in the user language).
4608          *
4609          * @since 1.20
4610          * @return Language
4611          */
4612         public function getPageViewLanguage() {
4613                 global $wgLang;
4614
4615                 if ( $this->isSpecialPage() ) {
4616                         // If the user chooses a variant, the content is actually
4617                         // in a language whose code is the variant code.
4618                         $variant = $wgLang->getPreferredVariant();
4619                         if ( $wgLang->getCode() !== $variant ) {
4620                                 return Language::factory( $variant );
4621                         }
4622
4623                         return $wgLang;
4624                 }
4625
4626                 //NOTE: can't be cached persistently, depends on user settings
4627                 //NOTE: ContentHandler::getPageViewLanguage() may need to load the content to determine the page language!
4628                 $contentHandler = ContentHandler::getForTitle( $this );
4629                 $pageLang = $contentHandler->getPageViewLanguage( $this );
4630                 return $pageLang;
4631         }
4632 }