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                 //@todo: ConversionTable should become a separate content model.
 935
 936                 return $this->getNamespace() == NS_MEDIAWIKI &&
 937                         strpos( $this->getText(), 'Conversiontable/' ) === 0;
 938         }
 939
 940         /**
 941          * Does that page contain wikitext, or it is JS, CSS or whatever?
 942          *
 943          * @return Bool
 944          */
 945         public function isWikitextPage() {
 946                 return $this->hasContentModel( CONTENT_MODEL_WIKITEXT );
 947         }
 948
 949         /**
 950          * Could this page contain custom CSS or JavaScript for the global UI.
 951          * This is generally true for pages in the MediaWiki namespace having CONTENT_MODEL_CSS
 952          * or CONTENT_MODEL_JAVASCRIPT.
 953          *
 954          * This method does *not* return true for per-user JS/CSS. Use isCssJsSubpage() for that!
 955          *
 956          * Note that this method should not return true for pages that contain and show "inactive" CSS or JS.
 957          *
 958          * @return Bool
 959          */
 960         public function isCssOrJsPage() {
 961                 $isCssOrJsPage = NS_MEDIAWIKI == $this->mNamespace
 962                         && ( $this->hasContentModel( CONTENT_MODEL_CSS )
 963                                 || $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
 964
 965                 #NOTE: this hook is also called in ContentHandler::getDefaultModel. It's called here again to make sure
 966                 #      hook funktions can force this method to return true even outside the mediawiki namespace.
 967
 968                 wfRunHooks( 'TitleIsCssOrJsPage', array( $this, &$isCssOrJsPage ) );
 969
 970                 return $isCssOrJsPage;
 971         }
 972
 973         /**
 974          * Is this a .css or .js subpage of a user page?
 975          * @return Bool
 976          */
 977         public function isCssJsSubpage() {
 978                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
 979                                 && ( $this->hasContentModel( CONTENT_MODEL_CSS )
 980                                         || $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) ) );
 981         }
 982
 983         /**
 984          * Trim down a .css or .js subpage title to get the corresponding skin name
 985          *
 986          * @return string containing skin name from .css or .js subpage title
 987          */
 988         public function getSkinFromCssJsSubpage() {
 989                 $subpage = explode( '/', $this->mTextform );
 990                 $subpage = $subpage[ count( $subpage ) - 1 ];
 991                 $lastdot = strrpos( $subpage, '.' );
 992                 if ( $lastdot === false )
 993                         return $subpage; # Never happens: only called for names ending in '.css' or '.js'
 994                 return substr( $subpage, 0, $lastdot );
 995         }
 996
 997         /**
 998          * Is this a .css subpage of a user page?
 999          *
1000          * @return Bool
1001          */
1002         public function isCssSubpage() {
1003                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
1004                         && $this->hasContentModel( CONTENT_MODEL_CSS ) );
1005         }
1006
1007         /**
1008          * Is this a .js subpage of a user page?
1009          *
1010          * @return Bool
1011          */
1012         public function isJsSubpage() {
1013                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
1014                         && $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
1015         }
1016
1017         /**
1018          * Is this a talk page of some sort?
1019          *
1020          * @return Bool
1021          */
1022         public function isTalkPage() {
1023                 return MWNamespace::isTalk( $this->getNamespace() );
1024         }
1025
1026         /**
1027          * Get a Title object associated with the talk page of this article
1028          *
1029          * @return Title the object for the talk page
1030          */
1031         public function getTalkPage() {
1032                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1033         }
1034
1035         /**
1036          * Get a title object associated with the subject page of this
1037          * talk page
1038          *
1039          * @return Title the object for the subject page
1040          */
1041         public function getSubjectPage() {
1042                 // Is this the same title?
1043                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
1044                 if ( $this->getNamespace() == $subjectNS ) {
1045                         return $this;
1046                 }
1047                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
1048         }
1049
1050         /**
1051          * Get the default namespace index, for when there is no namespace
1052          *
1053          * @return Int Default namespace index
1054          */
1055         public function getDefaultNamespace() {
1056                 return $this->mDefaultNamespace;
1057         }
1058
1059         /**
1060          * Get title for search index
1061          *
1062          * @return String a stripped-down title string ready for the
1063          *  search index
1064          */
1065         public function getIndexTitle() {
1066                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
1067         }
1068
1069         /**
1070          * Get the Title fragment (i.e.\ the bit after the #) in text form
1071          *
1072          * @return String Title fragment
1073          */
1074         public function getFragment() {
1075                 return $this->mFragment;
1076         }
1077
1078         /**
1079          * Get the fragment in URL form, including the "#" character if there is one
1080          * @return String Fragment in URL form
1081          */
1082         public function getFragmentForURL() {
1083                 if ( $this->mFragment == '' ) {
1084                         return '';
1085                 } else {
1086                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
1087                 }
1088         }
1089
1090         /**
1091          * Set the fragment for this title. Removes the first character from the
1092          * specified fragment before setting, so it assumes you're passing it with
1093          * an initial "#".
1094          *
1095          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
1096          * Still in active use privately.
1097          *
1098          * @param $fragment String text
1099          */
1100         public function setFragment( $fragment ) {
1101                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
1102         }
1103
1104         /**
1105          * Prefix some arbitrary text with the namespace or interwiki prefix
1106          * of this object
1107          *
1108          * @param $name String the text
1109          * @return String the prefixed text
1110          * @private
1111          */
1112         private function prefix( $name ) {
1113                 $p = '';
1114                 if ( $this->mInterwiki != '' ) {
1115                         $p = $this->mInterwiki . ':';
1116                 }
1117
1118                 if ( 0 != $this->mNamespace ) {
1119                         $p .= $this->getNsText() . ':';
1120                 }
1121                 return $p . $name;
1122         }
1123
1124         /**
1125          * Get the prefixed database key form
1126          *
1127          * @return String the prefixed title, with underscores and
1128          *  any interwiki and namespace prefixes
1129          */
1130         public function getPrefixedDBkey() {
1131                 $s = $this->prefix( $this->mDbkeyform );
1132                 $s = str_replace( ' ', '_', $s );
1133                 return $s;
1134         }
1135
1136         /**
1137          * Get the prefixed title with spaces.
1138          * This is the form usually used for display
1139          *
1140          * @return String the prefixed title, with spaces
1141          */
1142         public function getPrefixedText() {
1143                 // @todo FIXME: Bad usage of empty() ?
1144                 if ( empty( $this->mPrefixedText ) ) {
1145                         $s = $this->prefix( $this->mTextform );
1146                         $s = str_replace( '_', ' ', $s );
1147                         $this->mPrefixedText = $s;
1148                 }
1149                 return $this->mPrefixedText;
1150         }
1151
1152         /**
1153          * Return a string representation of this title
1154          *
1155          * @return String representation of this title
1156          */
1157         public function __toString() {
1158                 return $this->getPrefixedText();
1159         }
1160
1161         /**
1162          * Get the prefixed title with spaces, plus any fragment
1163          * (part beginning with '#')
1164          *
1165          * @return String the prefixed title, with spaces and the fragment, including '#'
1166          */
1167         public function getFullText() {
1168                 $text = $this->getPrefixedText();
1169                 if ( $this->mFragment != '' ) {
1170                         $text .= '#' . $this->mFragment;
1171                 }
1172                 return $text;
1173         }
1174
1175         /**
1176          * Get the base page name, i.e. the leftmost part before any slashes
1177          *
1178          * @return String Base name
1179          */
1180         public function getBaseText() {
1181                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1182                         return $this->getText();
1183                 }
1184
1185                 $parts = explode( '/', $this->getText() );
1186                 # Don't discard the real title if there's no subpage involved
1187                 if ( count( $parts ) > 1 ) {
1188                         unset( $parts[count( $parts ) - 1] );
1189                 }
1190                 return implode( '/', $parts );
1191         }
1192
1193         /**
1194          * Get the lowest-level subpage name, i.e. the rightmost part after any slashes
1195          *
1196          * @return String Subpage name
1197          */
1198         public function getSubpageText() {
1199                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1200                         return( $this->mTextform );
1201                 }
1202                 $parts = explode( '/', $this->mTextform );
1203                 return( $parts[count( $parts ) - 1] );
1204         }
1205
1206         /**
1207          * Get the HTML-escaped displayable text form.
1208          * Used for the title field in <a> tags.
1209          *
1210          * @return String the text, including any prefixes
1211          */
1212         public function getEscapedText() {
1213                 wfDeprecated( __METHOD__, '1.19' );
1214                 return htmlspecialchars( $this->getPrefixedText() );
1215         }
1216
1217         /**
1218          * Get a URL-encoded form of the subpage text
1219          *
1220          * @return String URL-encoded subpage name
1221          */
1222         public function getSubpageUrlForm() {
1223                 $text = $this->getSubpageText();
1224                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
1225                 return( $text );
1226         }
1227
1228         /**
1229          * Get a URL-encoded title (not an actual URL) including interwiki
1230          *
1231          * @return String the URL-encoded form
1232          */
1233         public function getPrefixedURL() {
1234                 $s = $this->prefix( $this->mDbkeyform );
1235                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
1236                 return $s;
1237         }
1238
1239         /**
1240          * Helper to fix up the get{Local,Full,Link,Canonical}URL args
1241          * get{Canonical,Full,Link,Local}URL methods accepted an optional
1242          * second argument named variant. This was deprecated in favor
1243          * of passing an array of option with a "variant" key
1244          * Once $query2 is removed for good, this helper can be dropped
1245          * andthe wfArrayToCGI moved to getLocalURL();
1246          *
1247          * @since 1.19 (r105919)
1248          * @param $query
1249          * @param $query2 bool
1250          * @return String
1251          */
1252         private static function fixUrlQueryArgs( $query, $query2 = false ) {
1253                 if( $query2 !== false ) {
1254                         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" );
1255                 }
1256                 if ( is_array( $query ) ) {
1257                         $query = wfArrayToCGI( $query );
1258                 }
1259                 if ( $query2 ) {
1260                         if ( is_string( $query2 ) ) {
1261                                 // $query2 is a string, we will consider this to be
1262                                 // a deprecated $variant argument and add it to the query
1263                                 $query2 = wfArrayToCGI( array( 'variant' => $query2 ) );
1264                         } else {
1265                                 $query2 = wfArrayToCGI( $query2 );
1266                         }
1267                         // If we have $query content add a & to it first
1268                         if ( $query ) {
1269                                 $query .= '&';
1270                         }
1271                         // Now append the queries together
1272                         $query .= $query2;
1273                 }
1274                 return $query;
1275         }
1276
1277         /**
1278          * Get a real URL referring to this title, with interwiki link and
1279          * fragment
1280          *
1281          * See getLocalURL for the arguments.
1282          *
1283          * @see self::getLocalURL
1284          * @see wfExpandUrl
1285          * @param $proto Protocol type to use in URL
1286          * @return String the URL
1287          */
1288         public function getFullURL( $query = '', $query2 = false, $proto = PROTO_RELATIVE ) {
1289                 $query = self::fixUrlQueryArgs( $query, $query2 );
1290
1291                 # Hand off all the decisions on urls to getLocalURL
1292                 $url = $this->getLocalURL( $query );
1293
1294                 # Expand the url to make it a full url. Note that getLocalURL has the
1295                 # potential to output full urls for a variety of reasons, so we use
1296                 # wfExpandUrl instead of simply prepending $wgServer
1297                 $url = wfExpandUrl( $url, $proto );
1298
1299                 # Finally, add the fragment.
1300                 $url .= $this->getFragmentForURL();
1301
1302                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
1303                 return $url;
1304         }
1305
1306         /**
1307          * Get a URL with no fragment or server name.  If this page is generated
1308          * with action=render, $wgServer is prepended.
1309          *
1310
1311          * @param $query string|array an optional query string,
1312          *   not used for interwiki     links. Can be specified as an associative array as well,
1313          *   e.g., array( 'action' => 'edit' ) (keys and values will be URL-escaped).
1314          *   Some query patterns will trigger various shorturl path replacements.
1315          * @param $query2 Mixed: An optional secondary query array. This one MUST
1316          *   be an array. If a string is passed it will be interpreted as a deprecated
1317          *   variant argument and urlencoded into a variant= argument.
1318          *   This second query argument will be added to the $query
1319          *   The second parameter is deprecated since 1.19. Pass it as a key,value
1320          *   pair in the first parameter array instead.
1321          *
1322          * @return String the URL
1323          */
1324         public function getLocalURL( $query = '', $query2 = false ) {
1325                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
1326
1327                 $query = self::fixUrlQueryArgs( $query, $query2 );
1328
1329                 $interwiki = Interwiki::fetch( $this->mInterwiki );
1330                 if ( $interwiki ) {
1331                         $namespace = $this->getNsText();
1332                         if ( $namespace != '' ) {
1333                                 # Can this actually happen? Interwikis shouldn't be parsed.
1334                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
1335                                 $namespace .= ':';
1336                         }
1337                         $url = $interwiki->getURL( $namespace . $this->getDBkey() );
1338                         $url = wfAppendQuery( $url, $query );
1339                 } else {
1340                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
1341                         if ( $query == '' ) {
1342                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
1343                                 wfRunHooks( 'GetLocalURL::Article', array( &$this, &$url ) );
1344                         } else {
1345                                 global $wgVariantArticlePath, $wgActionPaths;
1346                                 $url = false;
1347                                 $matches = array();
1348
1349                                 if ( !empty( $wgActionPaths ) &&
1350                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
1351                                 {
1352                                         $action = urldecode( $matches[2] );
1353                                         if ( isset( $wgActionPaths[$action] ) ) {
1354                                                 $query = $matches[1];
1355                                                 if ( isset( $matches[4] ) ) {
1356                                                         $query .= $matches[4];
1357                                                 }
1358                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
1359                                                 if ( $query != '' ) {
1360                                                         $url = wfAppendQuery( $url, $query );
1361                                                 }
1362                                         }
1363                                 }
1364
1365                                 if ( $url === false &&
1366                                         $wgVariantArticlePath &&
1367                                         $this->getPageLanguage()->hasVariants() &&
1368                                         preg_match( '/^variant=([^&]*)$/', $query, $matches ) )
1369                                 {
1370                                         $variant = urldecode( $matches[1] );
1371                                         if ( $this->getPageLanguage()->hasVariant( $variant ) ) {
1372                                                 // Only do the variant replacement if the given variant is a valid
1373                                                 // variant for the page's language.
1374                                                 $url = str_replace( '$2', urlencode( $variant ), $wgVariantArticlePath );
1375                                                 $url = str_replace( '$1', $dbkey, $url );
1376                                         }
1377                                 }
1378
1379                                 if ( $url === false ) {
1380                                         if ( $query == '-' ) {
1381                                                 $query = '';
1382                                         }
1383                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
1384                                 }
1385                         }
1386
1387                         wfRunHooks( 'GetLocalURL::Internal', array( &$this, &$url, $query ) );
1388
1389                         // @todo FIXME: This causes breakage in various places when we
1390                         // actually expected a local URL and end up with dupe prefixes.
1391                         if ( $wgRequest->getVal( 'action' ) == 'render' ) {
1392                                 $url = $wgServer . $url;
1393                         }
1394                 }
1395                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
1396                 return $url;
1397         }
1398
1399         /**
1400          * Get a URL that's the simplest URL that will be valid to link, locally,
1401          * to the current Title.  It includes the fragment, but does not include
1402          * the server unless action=render is used (or the link is external).  If
1403          * there's a fragment but the prefixed text is empty, we just return a link
1404          * to the fragment.
1405          *
1406          * The result obviously should not be URL-escaped, but does need to be
1407          * HTML-escaped if it's being output in HTML.
1408          *
1409          * See getLocalURL for the arguments.
1410          *
1411          * @see self::getLocalURL
1412          * @return String the URL
1413          */
1414         public function getLinkURL( $query = '', $query2 = false ) {
1415                 wfProfileIn( __METHOD__ );
1416                 if ( $this->isExternal() ) {
1417                         $ret = $this->getFullURL( $query, $query2 );
1418                 } elseif ( $this->getPrefixedText() === '' && $this->getFragment() !== '' ) {
1419                         $ret = $this->getFragmentForURL();
1420                 } else {
1421                         $ret = $this->getLocalURL( $query, $query2 ) . $this->getFragmentForURL();
1422                 }
1423                 wfProfileOut( __METHOD__ );
1424                 return $ret;
1425         }
1426
1427         /**
1428          * Get an HTML-escaped version of the URL form, suitable for
1429          * using in a link, without a server name or fragment
1430          *
1431          * See getLocalURL for the arguments.
1432          *
1433          * @see self::getLocalURL
1434          * @param $query string
1435          * @param $query2 bool|string
1436          * @return String the URL
1437          */
1438         public function escapeLocalURL( $query = '', $query2 = false ) {
1439                 wfDeprecated( __METHOD__, '1.19' );
1440                 return htmlspecialchars( $this->getLocalURL( $query, $query2 ) );
1441         }
1442
1443         /**
1444          * Get an HTML-escaped version of the URL form, suitable for
1445          * using in a link, including the server name and fragment
1446          *
1447          * See getLocalURL for the arguments.
1448          *
1449          * @see self::getLocalURL
1450          * @return String the URL
1451          */
1452         public function escapeFullURL( $query = '', $query2 = false ) {
1453                 wfDeprecated( __METHOD__, '1.19' );
1454                 return htmlspecialchars( $this->getFullURL( $query, $query2 ) );
1455         }
1456
1457         /**
1458          * Get the URL form for an internal link.
1459          * - Used in various Squid-related code, in case we have a different
1460          * internal hostname for the server from the exposed one.
1461          *
1462          * This uses $wgInternalServer to qualify the path, or $wgServer
1463          * if $wgInternalServer is not set. If the server variable used is
1464          * protocol-relative, the URL will be expanded to http://
1465          *
1466          * See getLocalURL for the arguments.
1467          *
1468          * @see self::getLocalURL
1469          * @return String the URL
1470          */
1471         public function getInternalURL( $query = '', $query2 = false ) {
1472                 global $wgInternalServer, $wgServer;
1473                 $query = self::fixUrlQueryArgs( $query, $query2 );
1474                 $server = $wgInternalServer !== false ? $wgInternalServer : $wgServer;
1475                 $url = wfExpandUrl( $server . $this->getLocalURL( $query ), PROTO_HTTP );
1476                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
1477                 return $url;
1478         }
1479
1480         /**
1481          * Get the URL for a canonical link, for use in things like IRC and
1482          * e-mail notifications. Uses $wgCanonicalServer and the
1483          * GetCanonicalURL hook.
1484          *
1485          * NOTE: Unlike getInternalURL(), the canonical URL includes the fragment
1486          *
1487          * See getLocalURL for the arguments.
1488          *
1489          * @see self::getLocalURL
1490          * @return string The URL
1491          * @since 1.18
1492          */
1493         public function getCanonicalURL( $query = '', $query2 = false ) {
1494                 $query = self::fixUrlQueryArgs( $query, $query2 );
1495                 $url = wfExpandUrl( $this->getLocalURL( $query ) . $this->getFragmentForURL(), PROTO_CANONICAL );
1496                 wfRunHooks( 'GetCanonicalURL', array( &$this, &$url, $query ) );
1497                 return $url;
1498         }
1499
1500         /**
1501          * HTML-escaped version of getCanonicalURL()
1502          *
1503          * See getLocalURL for the arguments.
1504          *
1505          * @see self::getLocalURL
1506          * @since 1.18
1507          * @return string
1508          */
1509         public function escapeCanonicalURL( $query = '', $query2 = false ) {
1510                 wfDeprecated( __METHOD__, '1.19' );
1511                 return htmlspecialchars( $this->getCanonicalURL( $query, $query2 ) );
1512         }
1513
1514         /**
1515          * Get the edit URL for this Title
1516          *
1517          * @return String the URL, or a null string if this is an
1518          *  interwiki link
1519          */
1520         public function getEditURL() {
1521                 if ( $this->mInterwiki != '' ) {
1522                         return '';
1523                 }
1524                 $s = $this->getLocalURL( 'action=edit' );
1525
1526                 return $s;
1527         }
1528
1529         /**
1530          * Is $wgUser watching this page?
1531          *
1532          * @deprecated in 1.20; use User::isWatched() instead.
1533          * @return Bool
1534          */
1535         public function userIsWatching() {
1536                 global $wgUser;
1537
1538                 if ( is_null( $this->mWatched ) ) {
1539                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn() ) {
1540                                 $this->mWatched = false;
1541                         } else {
1542                                 $this->mWatched = $wgUser->isWatched( $this );
1543                         }
1544                 }
1545                 return $this->mWatched;
1546         }
1547
1548         /**
1549          * Can $wgUser read this page?
1550          *
1551          * @deprecated in 1.19; use userCan(), quickUserCan() or getUserPermissionsErrors() instead
1552          * @return Bool
1553          * @todo fold these checks into userCan()
1554          */
1555         public function userCanRead() {
1556                 wfDeprecated( __METHOD__, '1.19' );
1557                 return $this->userCan( 'read' );
1558         }
1559
1560         /**
1561          * Can $user perform $action on this page?
1562          * This skips potentially expensive cascading permission checks
1563          * as well as avoids expensive error formatting
1564          *
1565          * Suitable for use for nonessential UI controls in common cases, but
1566          * _not_ for functional access control.
1567          *
1568          * May provide false positives, but should never provide a false negative.
1569          *
1570          * @param $action String action that permission needs to be checked for
1571          * @param $user User to check (since 1.19); $wgUser will be used if not
1572          *              provided.
1573          * @return Bool
1574          */
1575         public function quickUserCan( $action, $user = null ) {
1576                 return $this->userCan( $action, $user, false );
1577         }
1578
1579         /**
1580          * Can $user perform $action on this page?
1581          *
1582          * @param $action String action that permission needs to be checked for
1583          * @param $user User to check (since 1.19); $wgUser will be used if not
1584          *   provided.
1585          * @param $doExpensiveQueries Bool Set this to false to avoid doing
1586          *   unnecessary queries.
1587          * @return Bool
1588          */
1589         public function userCan( $action, $user = null, $doExpensiveQueries = true ) {
1590                 if ( !$user instanceof User ) {
1591                         global $wgUser;
1592                         $user = $wgUser;
1593                 }
1594                 return !count( $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries, true ) );
1595         }
1596
1597         /**
1598          * Can $user perform $action on this page?
1599          *
1600          * @todo FIXME: This *does not* check throttles (User::pingLimiter()).
1601          *
1602          * @param $action String action that permission needs to be checked for
1603          * @param $user User to check
1604          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary
1605          *   queries by skipping checks for cascading protections and user blocks.
1606          * @param $ignoreErrors Array of Strings Set this to a list of message keys
1607          *   whose corresponding errors may be ignored.
1608          * @return Array of arguments to wfMessage to explain permissions problems.
1609          */
1610         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1611                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1612
1613                 // Remove the errors being ignored.
1614                 foreach ( $errors as $index => $error ) {
1615                         $error_key = is_array( $error ) ? $error[0] : $error;
1616
1617                         if ( in_array( $error_key, $ignoreErrors ) ) {
1618                                 unset( $errors[$index] );
1619                         }
1620                 }
1621
1622                 return $errors;
1623         }
1624
1625         /**
1626          * Permissions checks that fail most often, and which are easiest to test.
1627          *
1628          * @param $action String the action to check
1629          * @param $user User user to check
1630          * @param $errors Array list of current errors
1631          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1632          * @param $short Boolean short circuit on first error
1633          *
1634          * @return Array list of errors
1635          */
1636         private function checkQuickPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1637                 if ( $action == 'create' ) {
1638                         if ( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1639                                  ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1640                                 $errors[] = $user->isAnon() ? array( 'nocreatetext' ) : array( 'nocreate-loggedin' );
1641                         }
1642                 } elseif ( $action == 'move' ) {
1643                         if ( !$user->isAllowed( 'move-rootuserpages' )
1644                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1645                                 // Show user page-specific message only if the user can move other pages
1646                                 $errors[] = array( 'cant-move-user-page' );
1647                         }
1648
1649                         // Check if user is allowed to move files if it's a file
1650                         if ( $this->mNamespace == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1651                                 $errors[] = array( 'movenotallowedfile' );
1652                         }
1653
1654                         if ( !$user->isAllowed( 'move' ) ) {
1655                                 // User can't move anything
1656                                 global $wgGroupPermissions;
1657                                 $userCanMove = false;
1658                                 if ( isset( $wgGroupPermissions['user']['move'] ) ) {
1659                                         $userCanMove = $wgGroupPermissions['user']['move'];
1660                                 }
1661                                 $autoconfirmedCanMove = false;
1662                                 if ( isset( $wgGroupPermissions['autoconfirmed']['move'] ) ) {
1663                                         $autoconfirmedCanMove = $wgGroupPermissions['autoconfirmed']['move'];
1664                                 }
1665                                 if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
1666                                         // custom message if logged-in users without any special rights can move
1667                                         $errors[] = array( 'movenologintext' );
1668                                 } else {
1669                                         $errors[] = array( 'movenotallowed' );
1670                                 }
1671                         }
1672                 } elseif ( $action == 'move-target' ) {
1673                         if ( !$user->isAllowed( 'move' ) ) {
1674                                 // User can't move anything
1675                                 $errors[] = array( 'movenotallowed' );
1676                         } elseif ( !$user->isAllowed( 'move-rootuserpages' )
1677                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1678                                 // Show user page-specific message only if the user can move other pages
1679                                 $errors[] = array( 'cant-move-to-user-page' );
1680                         }
1681                 } elseif ( !$user->isAllowed( $action ) ) {
1682                         $errors[] = $this->missingPermissionError( $action, $short );
1683                 }
1684
1685                 return $errors;
1686         }
1687
1688         /**
1689          * Add the resulting error code to the errors array
1690          *
1691          * @param $errors Array list of current errors
1692          * @param $result Mixed result of errors
1693          *
1694          * @return Array list of errors
1695          */
1696         private function resultToError( $errors, $result ) {
1697                 if ( is_array( $result ) && count( $result ) && !is_array( $result[0] ) ) {
1698                         // A single array representing an error
1699                         $errors[] = $result;
1700                 } elseif ( is_array( $result ) && is_array( $result[0] ) ) {
1701                         // A nested array representing multiple errors
1702                         $errors = array_merge( $errors, $result );
1703                 } elseif ( $result !== '' && is_string( $result ) ) {
1704                         // A string representing a message-id
1705                         $errors[] = array( $result );
1706                 } elseif ( $result === false ) {
1707                         // a generic "We don't want them to do that"
1708                         $errors[] = array( 'badaccess-group0' );
1709                 }
1710                 return $errors;
1711         }
1712
1713         /**
1714          * Check various permission hooks
1715          *
1716          * @param $action String the action to check
1717          * @param $user User user to check
1718          * @param $errors Array list of current errors
1719          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1720          * @param $short Boolean short circuit on first error
1721          *
1722          * @return Array list of errors
1723          */
1724         private function checkPermissionHooks( $action, $user, $errors, $doExpensiveQueries, $short ) {
1725                 // Use getUserPermissionsErrors instead
1726                 $result = '';
1727                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1728                         return $result ? array() : array( array( 'badaccess-group0' ) );
1729                 }
1730                 // Check getUserPermissionsErrors hook
1731                 if ( !wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1732                         $errors = $this->resultToError( $errors, $result );
1733                 }
1734                 // Check getUserPermissionsErrorsExpensive hook
1735                 if ( $doExpensiveQueries && !( $short && count( $errors ) > 0 ) &&
1736                          !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) ) ) {
1737                         $errors = $this->resultToError( $errors, $result );
1738                 }
1739
1740                 return $errors;
1741         }
1742
1743         /**
1744          * Check permissions on special pages & namespaces
1745          *
1746          * @param $action String the action to check
1747          * @param $user User user to check
1748          * @param $errors Array list of current errors
1749          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1750          * @param $short Boolean short circuit on first error
1751          *
1752          * @return Array list of errors
1753          */
1754         private function checkSpecialsAndNSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1755                 # Only 'createaccount' and 'execute' can be performed on
1756                 # special pages, which don't actually exist in the DB.
1757                 $specialOKActions = array( 'createaccount', 'execute', 'read' );
1758                 if ( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions ) ) {
1759                         $errors[] = array( 'ns-specialprotected' );
1760                 }
1761
1762                 # Check $wgNamespaceProtection for restricted namespaces
1763                 if ( $this->isNamespaceProtected( $user ) ) {
1764                         $ns = $this->mNamespace == NS_MAIN ?
1765                                 wfMessage( 'nstab-main' )->text() : $this->getNsText();
1766                         $errors[] = $this->mNamespace == NS_MEDIAWIKI ?
1767                                 array( 'protectedinterface' ) : array( 'namespaceprotected',  $ns );
1768                 }
1769
1770                 return $errors;
1771         }
1772
1773         /**
1774          * Check CSS/JS sub-page permissions
1775          *
1776          * @param $action String the action to check
1777          * @param $user User user to check
1778          * @param $errors Array list of current errors
1779          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1780          * @param $short Boolean short circuit on first error
1781          *
1782          * @return Array list of errors
1783          */
1784         private function checkCSSandJSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1785                 # Protect css/js subpages of user pages
1786                 # XXX: this might be better using restrictions
1787                 # XXX: right 'editusercssjs' is deprecated, for backward compatibility only
1788                 if ( $action != 'patrol' && !$user->isAllowed( 'editusercssjs' )
1789                                 && !preg_match( '/^' . preg_quote( $user->getName(), '/' ) . '\//', $this->mTextform ) ) {
1790                         if ( $this->isCssSubpage() && !$user->isAllowed( 'editusercss' ) ) {
1791                                 $errors[] = array( 'customcssprotected' );
1792                         } elseif ( $this->isJsSubpage() && !$user->isAllowed( 'edituserjs' ) ) {
1793                                 $errors[] = array( 'customjsprotected' );
1794                         }
1795                 }
1796
1797                 return $errors;
1798         }
1799
1800         /**
1801          * Check against page_restrictions table requirements on this
1802          * page. The user must possess all required rights for this
1803          * action.
1804          *
1805          * @param $action String the action to check
1806          * @param $user User user to check
1807          * @param $errors Array list of current errors
1808          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1809          * @param $short Boolean short circuit on first error
1810          *
1811          * @return Array list of errors
1812          */
1813         private function checkPageRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1814                 foreach ( $this->getRestrictions( $action ) as $right ) {
1815                         // Backwards compatibility, rewrite sysop -> protect
1816                         if ( $right == 'sysop' ) {
1817                                 $right = 'protect';
1818                         }
1819                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1820                                 // Users with 'editprotected' permission can edit protected pages
1821                                 // without cascading option turned on.
1822                                 if ( $action != 'edit' || !$user->isAllowed( 'editprotected' )
1823                                         || $this->mCascadeRestriction )
1824                                 {
1825                                         $errors[] = array( 'protectedpagetext', $right );
1826                                 }
1827                         }
1828                 }
1829
1830                 return $errors;
1831         }
1832
1833         /**
1834          * Check restrictions on cascading pages.
1835          *
1836          * @param $action String the action to check
1837          * @param $user User to check
1838          * @param $errors Array list of current errors
1839          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1840          * @param $short Boolean short circuit on first error
1841          *
1842          * @return Array list of errors
1843          */
1844         private function checkCascadingSourcesRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1845                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1846                         # We /could/ use the protection level on the source page, but it's
1847                         # fairly ugly as we have to establish a precedence hierarchy for pages
1848                         # included by multiple cascade-protected pages. So just restrict
1849                         # it to people with 'protect' permission, as they could remove the
1850                         # protection anyway.
1851                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1852                         # Cascading protection depends on more than this page...
1853                         # Several cascading protected pages may include this page...
1854                         # Check each cascading level
1855                         # This is only for protection restrictions, not for all actions
1856                         if ( isset( $restrictions[$action] ) ) {
1857                                 foreach ( $restrictions[$action] as $right ) {
1858                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1859                                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1860                                                 $pages = '';
1861                                                 foreach ( $cascadingSources as $page )
1862                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1863                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1864                                         }
1865                                 }
1866                         }
1867                 }
1868
1869                 return $errors;
1870         }
1871
1872         /**
1873          * Check action permissions not already checked in checkQuickPermissions
1874          *
1875          * @param $action String the action to check
1876          * @param $user User to check
1877          * @param $errors Array list of current errors
1878          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1879          * @param $short Boolean short circuit on first error
1880          *
1881          * @return Array list of errors
1882          */
1883         private function checkActionPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1884                 global $wgDeleteRevisionsLimit, $wgLang;
1885
1886                 if ( $action == 'protect' ) {
1887                         if ( count( $this->getUserPermissionsErrorsInternal( 'edit', $user, $doExpensiveQueries, true ) ) ) {
1888                                 // If they can't edit, they shouldn't protect.
1889                                 $errors[] = array( 'protect-cantedit' );
1890                         }
1891                 } elseif ( $action == 'create' ) {
1892                         $title_protection = $this->getTitleProtection();
1893                         if( $title_protection ) {
1894                                 if( $title_protection['pt_create_perm'] == 'sysop' ) {
1895                                         $title_protection['pt_create_perm'] = 'protect'; // B/C
1896                                 }
1897                                 if( $title_protection['pt_create_perm'] == '' ||
1898                                         !$user->isAllowed( $title_protection['pt_create_perm'] ) )
1899                                 {
1900                                         $errors[] = array( 'titleprotected', User::whoIs( $title_protection['pt_user'] ), $title_protection['pt_reason'] );
1901                                 }
1902                         }
1903                 } elseif ( $action == 'move' ) {
1904                         // Check for immobile pages
1905                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1906                                 // Specific message for this case
1907                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1908                         } elseif ( !$this->isMovable() ) {
1909                                 // Less specific message for rarer cases
1910                                 $errors[] = array( 'immobile-source-page' );
1911                         }
1912                 } elseif ( $action == 'move-target' ) {
1913                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1914                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1915                         } elseif ( !$this->isMovable() ) {
1916                                 $errors[] = array( 'immobile-target-page' );
1917                         }
1918                 } elseif ( $action == 'delete' ) {
1919                         if ( $doExpensiveQueries && $wgDeleteRevisionsLimit
1920                                 && !$this->userCan( 'bigdelete', $user ) && $this->isBigDeletion() )
1921                         {
1922                                 $errors[] = array( 'delete-toobig', $wgLang->formatNum( $wgDeleteRevisionsLimit ) );
1923                         }
1924                 }
1925                 return $errors;
1926         }
1927
1928         /**
1929          * Check that the user isn't blocked from editting.
1930          *
1931          * @param $action String the action to check
1932          * @param $user User to check
1933          * @param $errors Array list of current errors
1934          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1935          * @param $short Boolean short circuit on first error
1936          *
1937          * @return Array list of errors
1938          */
1939         private function checkUserBlock( $action, $user, $errors, $doExpensiveQueries, $short ) {
1940                 // Account creation blocks handled at userlogin.
1941                 // Unblocking handled in SpecialUnblock
1942                 if( !$doExpensiveQueries || in_array( $action, array( 'createaccount', 'unblock' ) ) ) {
1943                         return $errors;
1944                 }
1945
1946                 global $wgContLang, $wgLang, $wgEmailConfirmToEdit;
1947
1948                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() ) {
1949                         $errors[] = array( 'confirmedittext' );
1950                 }
1951
1952                 if ( ( $action == 'edit' || $action == 'create' ) && !$user->isBlockedFrom( $this ) ) {
1953                         // Don't block the user from editing their own talk page unless they've been
1954                         // explicitly blocked from that too.
1955                 } elseif( $user->isBlocked() && $user->mBlock->prevents( $action ) !== false ) {
1956                         $block = $user->getBlock();
1957
1958                         // This is from OutputPage::blockedPage
1959                         // Copied at r23888 by werdna
1960
1961                         $id = $user->blockedBy();
1962                         $reason = $user->blockedFor();
1963                         if ( $reason == '' ) {
1964                                 $reason = wfMessage( 'blockednoreason' )->text();
1965                         }
1966                         $ip = $user->getRequest()->getIP();
1967
1968                         if ( is_numeric( $id ) ) {
1969                                 $name = User::whoIs( $id );
1970                         } else {
1971                                 $name = $id;
1972                         }
1973
1974                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1975                         $blockid = $block->getId();
1976                         $blockExpiry = $block->getExpiry();
1977                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $block->mTimestamp ), true );
1978                         if ( $blockExpiry == 'infinity' ) {
1979                                 $blockExpiry = wfMessage( 'infiniteblock' )->text();
1980                         } else {
1981                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1982                         }
1983
1984                         $intended = strval( $block->getTarget() );
1985
1986                         $errors[] = array( ( $block->mAuto ? 'autoblockedtext' : 'blockedtext' ), $link, $reason, $ip, $name,
1987                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
1988                 }
1989
1990                 return $errors;
1991         }
1992
1993         /**
1994          * Check that the user is allowed to read this page.
1995          *
1996          * @param $action String the action to check
1997          * @param $user User to check
1998          * @param $errors Array list of current errors
1999          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
2000          * @param $short Boolean short circuit on first error
2001          *
2002          * @return Array list of errors
2003          */
2004         private function checkReadPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
2005                 global $wgWhitelistRead, $wgGroupPermissions, $wgRevokePermissions;
2006                 static $useShortcut = null;
2007
2008                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
2009                 if ( is_null( $useShortcut ) ) {
2010                         $useShortcut = true;
2011                         if ( empty( $wgGroupPermissions['*']['read'] ) ) {
2012                                 # Not a public wiki, so no shortcut
2013                                 $useShortcut = false;
2014                         } elseif ( !empty( $wgRevokePermissions ) ) {
2015                                 /**
2016                                  * Iterate through each group with permissions being revoked (key not included since we don't care
2017                                  * what the group name is), then check if the read permission is being revoked. If it is, then
2018                                  * we don't use the shortcut below since the user might not be able to read, even though anon
2019                                  * reading is allowed.
2020                                  */
2021                                 foreach ( $wgRevokePermissions as $perms ) {
2022                                         if ( !empty( $perms['read'] ) ) {
2023                                                 # We might be removing the read right from the user, so no shortcut
2024                                                 $useShortcut = false;
2025                                                 break;
2026                                         }
2027                                 }
2028                         }
2029                 }
2030
2031                 $whitelisted = false;
2032                 if ( $useShortcut ) {
2033                         # Shortcut for public wikis, allows skipping quite a bit of code
2034                         $whitelisted = true;
2035                 } elseif ( $user->isAllowed( 'read' ) ) {
2036                         # If the user is allowed to read pages, he is allowed to read all pages
2037                         $whitelisted = true;
2038                 } elseif ( $this->isSpecial( 'Userlogin' )
2039                         || $this->isSpecial( 'ChangePassword' )
2040                         || $this->isSpecial( 'PasswordReset' )
2041                 ) {
2042                         # Always grant access to the login page.
2043                         # Even anons need to be able to log in.
2044                         $whitelisted = true;
2045                 } elseif ( is_array( $wgWhitelistRead ) && count( $wgWhitelistRead ) ) {
2046                         # Time to check the whitelist
2047                         # Only do these checks is there's something to check against
2048                         $name = $this->getPrefixedText();
2049                         $dbName = $this->getPrefixedDBKey();
2050
2051                         // Check for explicit whitelisting with and without underscores
2052                         if ( in_array( $name, $wgWhitelistRead, true ) || in_array( $dbName, $wgWhitelistRead, true ) ) {
2053                                 $whitelisted = true;
2054                         } elseif ( $this->getNamespace() == NS_MAIN ) {
2055                                 # Old settings might have the title prefixed with
2056                                 # a colon for main-namespace pages
2057                                 if ( in_array( ':' . $name, $wgWhitelistRead ) ) {
2058                                         $whitelisted = true;
2059                                 }
2060                         } elseif ( $this->isSpecialPage() ) {
2061                                 # If it's a special page, ditch the subpage bit and check again
2062                                 $name = $this->getDBkey();
2063                                 list( $name, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $name );
2064                                 if ( $name !== false ) {
2065                                         $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
2066                                         if ( in_array( $pure, $wgWhitelistRead, true ) ) {
2067                                                 $whitelisted = true;
2068                                         }
2069                                 }
2070                         }
2071                 }
2072
2073                 if ( !$whitelisted ) {
2074                         # If the title is not whitelisted, give extensions a chance to do so...
2075                         wfRunHooks( 'TitleReadWhitelist', array( $this, $user, &$whitelisted ) );
2076                         if ( !$whitelisted ) {
2077                                 $errors[] = $this->missingPermissionError( $action, $short );
2078                         }
2079                 }
2080
2081                 return $errors;
2082         }
2083
2084         /**
2085          * Get a description array when the user doesn't have the right to perform
2086          * $action (i.e. when User::isAllowed() returns false)
2087          *
2088          * @param $action String the action to check
2089          * @param $short Boolean short circuit on first error
2090          * @return Array list of errors
2091          */
2092         private function missingPermissionError( $action, $short ) {
2093                 // We avoid expensive display logic for quickUserCan's and such
2094                 if ( $short ) {
2095                         return array( 'badaccess-group0' );
2096                 }
2097
2098                 $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
2099                         User::getGroupsWithPermission( $action ) );
2100
2101                 if ( count( $groups ) ) {
2102                         global $wgLang;
2103                         return array(
2104                                 'badaccess-groups',
2105                                 $wgLang->commaList( $groups ),
2106                                 count( $groups )
2107                         );
2108                 } else {
2109                         return array( 'badaccess-group0' );
2110                 }
2111         }
2112
2113         /**
2114          * Can $user perform $action on this page? This is an internal function,
2115          * which checks ONLY that previously checked by userCan (i.e. it leaves out
2116          * checks on wfReadOnly() and blocks)
2117          *
2118          * @param $action String action that permission needs to be checked for
2119          * @param $user User to check
2120          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary queries.
2121          * @param $short Bool Set this to true to stop after the first permission error.
2122          * @return Array of arrays of the arguments to wfMessage to explain permissions problems.
2123          */
2124         protected function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true, $short = false ) {
2125                 wfProfileIn( __METHOD__ );
2126
2127                 # Read has special handling
2128                 if ( $action == 'read' ) {
2129                         $checks = array(
2130                                 'checkPermissionHooks',
2131                                 'checkReadPermissions',
2132                         );
2133                 } else {
2134                         $checks = array(
2135                                 'checkQuickPermissions',
2136                                 'checkPermissionHooks',
2137                                 'checkSpecialsAndNSPermissions',
2138                                 'checkCSSandJSPermissions',
2139                                 'checkPageRestrictions',
2140                                 'checkCascadingSourcesRestrictions',
2141                                 'checkActionPermissions',
2142                                 'checkUserBlock'
2143                         );
2144                 }
2145
2146                 $errors = array();
2147                 while( count( $checks ) > 0 &&
2148                                 !( $short && count( $errors ) > 0 ) ) {
2149                         $method = array_shift( $checks );
2150                         $errors = $this->$method( $action, $user, $errors, $doExpensiveQueries, $short );
2151                 }
2152
2153                 wfProfileOut( __METHOD__ );
2154                 return $errors;
2155         }
2156
2157         /**
2158          * Protect css subpages of user pages: can $wgUser edit
2159          * this page?
2160          *
2161          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2162          * @return Bool
2163          */
2164         public function userCanEditCssSubpage() {
2165                 global $wgUser;
2166                 wfDeprecated( __METHOD__, '1.19' );
2167                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'editusercss' ) )
2168                         || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2169         }
2170
2171         /**
2172          * Protect js subpages of user pages: can $wgUser edit
2173          * this page?
2174          *
2175          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2176          * @return Bool
2177          */
2178         public function userCanEditJsSubpage() {
2179                 global $wgUser;
2180                 wfDeprecated( __METHOD__, '1.19' );
2181                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'edituserjs' ) )
2182                            || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2183         }
2184
2185         /**
2186          * Get a filtered list of all restriction types supported by this wiki.
2187          * @param bool $exists True to get all restriction types that apply to
2188          * titles that do exist, False for all restriction types that apply to
2189          * titles that do not exist
2190          * @return array
2191          */
2192         public static function getFilteredRestrictionTypes( $exists = true ) {
2193                 global $wgRestrictionTypes;
2194                 $types = $wgRestrictionTypes;
2195                 if ( $exists ) {
2196                         # Remove the create restriction for existing titles
2197                         $types = array_diff( $types, array( 'create' ) );
2198                 } else {
2199                         # Only the create and upload restrictions apply to non-existing titles
2200                         $types = array_intersect( $types, array( 'create', 'upload' ) );
2201                 }
2202                 return $types;
2203         }
2204
2205         /**
2206          * Returns restriction types for the current Title
2207          *
2208          * @return array applicable restriction types
2209          */
2210         public function getRestrictionTypes() {
2211                 if ( $this->isSpecialPage() ) {
2212                         return array();
2213                 }
2214
2215                 $types = self::getFilteredRestrictionTypes( $this->exists() );
2216
2217                 if ( $this->getNamespace() != NS_FILE ) {
2218                         # Remove the upload restriction for non-file titles
2219                         $types = array_diff( $types, array( 'upload' ) );
2220                 }
2221
2222                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
2223
2224                 wfDebug( __METHOD__ . ': applicable restrictions to [[' .
2225                         $this->getPrefixedText() . ']] are {' . implode( ',', $types ) . "}\n" );
2226
2227                 return $types;
2228         }
2229
2230         /**
2231          * Is this title subject to title protection?
2232          * Title protection is the one applied against creation of such title.
2233          *
2234          * @return Mixed An associative array representing any existent title
2235          *   protection, or false if there's none.
2236          */
2237         private function getTitleProtection() {
2238                 // Can't protect pages in special namespaces
2239                 if ( $this->getNamespace() < 0 ) {
2240                         return false;
2241                 }
2242
2243                 // Can't protect pages that exist.
2244                 if ( $this->exists() ) {
2245                         return false;
2246                 }
2247
2248                 if ( !isset( $this->mTitleProtection ) ) {
2249                         $dbr = wfGetDB( DB_SLAVE );
2250                         $res = $dbr->select( 'protected_titles', '*',
2251                                 array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2252                                 __METHOD__ );
2253
2254                         // fetchRow returns false if there are no rows.
2255                         $this->mTitleProtection = $dbr->fetchRow( $res );
2256                 }
2257                 return $this->mTitleProtection;
2258         }
2259
2260         /**
2261          * Update the title protection status
2262          *
2263          * @deprecated in 1.19; will be removed in 1.20. Use WikiPage::doUpdateRestrictions() instead.
2264          * @param $create_perm String Permission required for creation
2265          * @param $reason String Reason for protection
2266          * @param $expiry String Expiry timestamp
2267          * @return boolean true
2268          */
2269         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
2270                 wfDeprecated( __METHOD__, '1.19' );
2271
2272                 global $wgUser;
2273
2274                 $limit = array( 'create' => $create_perm );
2275                 $expiry = array( 'create' => $expiry );
2276
2277                 $page = WikiPage::factory( $this );
2278                 $status = $page->doUpdateRestrictions( $limit, $expiry, false, $reason, $wgUser );
2279
2280                 return $status->isOK();
2281         }
2282
2283         /**
2284          * Remove any title protection due to page existing
2285          */
2286         public function deleteTitleProtection() {
2287                 $dbw = wfGetDB( DB_MASTER );
2288
2289                 $dbw->delete(
2290                         'protected_titles',
2291                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2292                         __METHOD__
2293                 );
2294                 $this->mTitleProtection = false;
2295         }
2296
2297         /**
2298          * Is this page "semi-protected" - the *only* protection is autoconfirm?
2299          *
2300          * @param $action String Action to check (default: edit)
2301          * @return Bool
2302          */
2303         public function isSemiProtected( $action = 'edit' ) {
2304                 if ( $this->exists() ) {
2305                         $restrictions = $this->getRestrictions( $action );
2306                         if ( count( $restrictions ) > 0 ) {
2307                                 foreach ( $restrictions as $restriction ) {
2308                                         if ( strtolower( $restriction ) != 'autoconfirmed' ) {
2309                                                 return false;
2310                                         }
2311                                 }
2312                         } else {
2313                                 # Not protected
2314                                 return false;
2315                         }
2316                         return true;
2317                 } else {
2318                         # If it doesn't exist, it can't be protected
2319                         return false;
2320                 }
2321         }
2322
2323         /**
2324          * Does the title correspond to a protected article?
2325          *
2326          * @param $action String the action the page is protected from,
2327          * by default checks all actions.
2328          * @return Bool
2329          */
2330         public function isProtected( $action = '' ) {
2331                 global $wgRestrictionLevels;
2332
2333                 $restrictionTypes = $this->getRestrictionTypes();
2334
2335                 # Special pages have inherent protection
2336                 if( $this->isSpecialPage() ) {
2337                         return true;
2338                 }
2339
2340                 # Check regular protection levels
2341                 foreach ( $restrictionTypes as $type ) {
2342                         if ( $action == $type || $action == '' ) {
2343                                 $r = $this->getRestrictions( $type );
2344                                 foreach ( $wgRestrictionLevels as $level ) {
2345                                         if ( in_array( $level, $r ) && $level != '' ) {
2346                                                 return true;
2347                                         }
2348                                 }
2349                         }
2350                 }
2351
2352                 return false;
2353         }
2354
2355         /**
2356          * Determines if $user is unable to edit this page because it has been protected
2357          * by $wgNamespaceProtection.
2358          *
2359          * @param $user User object to check permissions
2360          * @return Bool
2361          */
2362         public function isNamespaceProtected( User $user ) {
2363                 global $wgNamespaceProtection;
2364
2365                 if ( isset( $wgNamespaceProtection[$this->mNamespace] ) ) {
2366                         foreach ( (array)$wgNamespaceProtection[$this->mNamespace] as $right ) {
2367                                 if ( $right != '' && !$user->isAllowed( $right ) ) {
2368                                         return true;
2369                                 }
2370                         }
2371                 }
2372                 return false;
2373         }
2374
2375         /**
2376          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
2377          *
2378          * @return Bool If the page is subject to cascading restrictions.
2379          */
2380         public function isCascadeProtected() {
2381                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
2382                 return ( $sources > 0 );
2383         }
2384
2385         /**
2386          * Cascading protection: Get the source of any cascading restrictions on this page.
2387          *
2388          * @param $getPages Bool Whether or not to retrieve the actual pages
2389          *        that the restrictions have come from.
2390          * @return Mixed Array of Title objects of the pages from which cascading restrictions
2391          *     have come, false for none, or true if such restrictions exist, but $getPages
2392          *     was not set.  The restriction array is an array of each type, each of which
2393          *     contains a array of unique groups.
2394          */
2395         public function getCascadeProtectionSources( $getPages = true ) {
2396                 global $wgContLang;
2397                 $pagerestrictions = array();
2398
2399                 if ( isset( $this->mCascadeSources ) && $getPages ) {
2400                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
2401                 } elseif ( isset( $this->mHasCascadingRestrictions ) && !$getPages ) {
2402                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
2403                 }
2404
2405                 wfProfileIn( __METHOD__ );
2406
2407                 $dbr = wfGetDB( DB_SLAVE );
2408
2409                 if ( $this->getNamespace() == NS_FILE ) {
2410                         $tables = array( 'imagelinks', 'page_restrictions' );
2411                         $where_clauses = array(
2412                                 'il_to' => $this->getDBkey(),
2413                                 'il_from=pr_page',
2414                                 'pr_cascade' => 1
2415                         );
2416                 } else {
2417                         $tables = array( 'templatelinks', 'page_restrictions' );
2418                         $where_clauses = array(
2419                                 'tl_namespace' => $this->getNamespace(),
2420                                 'tl_title' => $this->getDBkey(),
2421                                 'tl_from=pr_page',
2422                                 'pr_cascade' => 1
2423                         );
2424                 }
2425
2426                 if ( $getPages ) {
2427                         $cols = array( 'pr_page', 'page_namespace', 'page_title',
2428                                                    'pr_expiry', 'pr_type', 'pr_level' );
2429                         $where_clauses[] = 'page_id=pr_page';
2430                         $tables[] = 'page';
2431                 } else {
2432                         $cols = array( 'pr_expiry' );
2433                 }
2434
2435                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
2436
2437                 $sources = $getPages ? array() : false;
2438                 $now = wfTimestampNow();
2439                 $purgeExpired = false;
2440
2441                 foreach ( $res as $row ) {
2442                         $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2443                         if ( $expiry > $now ) {
2444                                 if ( $getPages ) {
2445                                         $page_id = $row->pr_page;
2446                                         $page_ns = $row->page_namespace;
2447                                         $page_title = $row->page_title;
2448                                         $sources[$page_id] = Title::makeTitle( $page_ns, $page_title );
2449                                         # Add groups needed for each restriction type if its not already there
2450                                         # Make sure this restriction type still exists
2451
2452                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
2453                                                 $pagerestrictions[$row->pr_type] = array();
2454                                         }
2455
2456                                         if ( isset( $pagerestrictions[$row->pr_type] ) &&
2457                                                  !in_array( $row->pr_level, $pagerestrictions[$row->pr_type] ) ) {
2458                                                 $pagerestrictions[$row->pr_type][] = $row->pr_level;
2459                                         }
2460                                 } else {
2461                                         $sources = true;
2462                                 }
2463                         } else {
2464                                 // Trigger lazy purge of expired restrictions from the db
2465                                 $purgeExpired = true;
2466                         }
2467                 }
2468                 if ( $purgeExpired ) {
2469                         Title::purgeExpiredRestrictions();
2470                 }
2471
2472                 if ( $getPages ) {
2473                         $this->mCascadeSources = $sources;
2474                         $this->mCascadingRestrictions = $pagerestrictions;
2475                 } else {
2476                         $this->mHasCascadingRestrictions = $sources;
2477                 }
2478
2479                 wfProfileOut( __METHOD__ );
2480                 return array( $sources, $pagerestrictions );
2481         }
2482
2483         /**
2484          * Accessor/initialisation for mRestrictions
2485          *
2486          * @param $action String action that permission needs to be checked for
2487          * @return Array of Strings the array of groups allowed to edit this article
2488          */
2489         public function getRestrictions( $action ) {
2490                 if ( !$this->mRestrictionsLoaded ) {
2491                         $this->loadRestrictions();
2492                 }
2493                 return isset( $this->mRestrictions[$action] )
2494                                 ? $this->mRestrictions[$action]
2495                                 : array();
2496         }
2497
2498         /**
2499          * Get the expiry time for the restriction against a given action
2500          *
2501          * @param $action
2502          * @return String|Bool 14-char timestamp, or 'infinity' if the page is protected forever
2503          *     or not protected at all, or false if the action is not recognised.
2504          */
2505         public function getRestrictionExpiry( $action ) {
2506                 if ( !$this->mRestrictionsLoaded ) {
2507                         $this->loadRestrictions();
2508                 }
2509                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2510         }
2511
2512         /**
2513          * Returns cascading restrictions for the current article
2514          *
2515          * @return Boolean
2516          */
2517         function areRestrictionsCascading() {
2518                 if ( !$this->mRestrictionsLoaded ) {
2519                         $this->loadRestrictions();
2520                 }
2521
2522                 return $this->mCascadeRestriction;
2523         }
2524
2525         /**
2526          * Loads a string into mRestrictions array
2527          *
2528          * @param $res Resource restrictions as an SQL result.
2529          * @param $oldFashionedRestrictions String comma-separated list of page
2530          *        restrictions from page table (pre 1.10)
2531          */
2532         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
2533                 $rows = array();
2534
2535                 foreach ( $res as $row ) {
2536                         $rows[] = $row;
2537                 }
2538
2539                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
2540         }
2541
2542         /**
2543          * Compiles list of active page restrictions from both page table (pre 1.10)
2544          * and page_restrictions table for this existing page.
2545          * Public for usage by LiquidThreads.
2546          *
2547          * @param $rows array of db result objects
2548          * @param $oldFashionedRestrictions string comma-separated list of page
2549          *        restrictions from page table (pre 1.10)
2550          */
2551         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
2552                 global $wgContLang;
2553                 $dbr = wfGetDB( DB_SLAVE );
2554
2555                 $restrictionTypes = $this->getRestrictionTypes();
2556
2557                 foreach ( $restrictionTypes as $type ) {
2558                         $this->mRestrictions[$type] = array();
2559                         $this->mRestrictionsExpiry[$type] = $wgContLang->formatExpiry( '', TS_MW );
2560                 }
2561
2562                 $this->mCascadeRestriction = false;
2563
2564                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2565
2566                 if ( $oldFashionedRestrictions === null ) {
2567                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2568                                 array( 'page_id' => $this->getArticleID() ), __METHOD__ );
2569                 }
2570
2571                 if ( $oldFashionedRestrictions != '' ) {
2572
2573                         foreach ( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2574                                 $temp = explode( '=', trim( $restrict ) );
2575                                 if ( count( $temp ) == 1 ) {
2576                                         // old old format should be treated as edit/move restriction
2577                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2578                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2579                                 } else {
2580                                         $restriction = trim( $temp[1] );
2581                                         if( $restriction != '' ) { //some old entries are empty
2582                                                 $this->mRestrictions[$temp[0]] = explode( ',', $restriction );
2583                                         }
2584                                 }
2585                         }
2586
2587                         $this->mOldRestrictions = true;
2588
2589                 }
2590
2591                 if ( count( $rows ) ) {
2592                         # Current system - load second to make them override.
2593                         $now = wfTimestampNow();
2594                         $purgeExpired = false;
2595
2596                         # Cycle through all the restrictions.
2597                         foreach ( $rows as $row ) {
2598
2599                                 // Don't take care of restrictions types that aren't allowed
2600                                 if ( !in_array( $row->pr_type, $restrictionTypes ) )
2601                                         continue;
2602
2603                                 // This code should be refactored, now that it's being used more generally,
2604                                 // But I don't really see any harm in leaving it in Block for now -werdna
2605                                 $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2606
2607                                 // Only apply the restrictions if they haven't expired!
2608                                 if ( !$expiry || $expiry > $now ) {
2609                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2610                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2611
2612                                         $this->mCascadeRestriction |= $row->pr_cascade;
2613                                 } else {
2614                                         // Trigger a lazy purge of expired restrictions
2615                                         $purgeExpired = true;
2616                                 }
2617                         }
2618
2619                         if ( $purgeExpired ) {
2620                                 Title::purgeExpiredRestrictions();
2621                         }
2622                 }
2623
2624                 $this->mRestrictionsLoaded = true;
2625         }
2626
2627         /**
2628          * Load restrictions from the page_restrictions table
2629          *
2630          * @param $oldFashionedRestrictions String comma-separated list of page
2631          *        restrictions from page table (pre 1.10)
2632          */
2633         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2634                 global $wgContLang;
2635                 if ( !$this->mRestrictionsLoaded ) {
2636                         if ( $this->exists() ) {
2637                                 $dbr = wfGetDB( DB_SLAVE );
2638
2639                                 $res = $dbr->select(
2640                                         'page_restrictions',
2641                                         '*',
2642                                         array( 'pr_page' => $this->getArticleID() ),
2643                                         __METHOD__
2644                                 );
2645
2646                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2647                         } else {
2648                                 $title_protection = $this->getTitleProtection();
2649
2650                                 if ( $title_protection ) {
2651                                         $now = wfTimestampNow();
2652                                         $expiry = $wgContLang->formatExpiry( $title_protection['pt_expiry'], TS_MW );
2653
2654                                         if ( !$expiry || $expiry > $now ) {
2655                                                 // Apply the restrictions
2656                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2657                                                 $this->mRestrictions['create'] = explode( ',', trim( $title_protection['pt_create_perm'] ) );
2658                                         } else { // Get rid of the old restrictions
2659                                                 Title::purgeExpiredRestrictions();
2660                                                 $this->mTitleProtection = false;
2661                                         }
2662                                 } else {
2663                                         $this->mRestrictionsExpiry['create'] = $wgContLang->formatExpiry( '', TS_MW );
2664                                 }
2665                                 $this->mRestrictionsLoaded = true;
2666                         }
2667                 }
2668         }
2669
2670         /**
2671          * Flush the protection cache in this object and force reload from the database.
2672          * This is used when updating protection from WikiPage::doUpdateRestrictions().
2673          */
2674         public function flushRestrictions() {
2675                 $this->mRestrictionsLoaded = false;
2676                 $this->mTitleProtection = null;
2677         }
2678
2679         /**
2680          * Purge expired restrictions from the page_restrictions table
2681          */
2682         static function purgeExpiredRestrictions() {
2683                 $dbw = wfGetDB( DB_MASTER );
2684                 $dbw->delete(
2685                         'page_restrictions',
2686                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2687                         __METHOD__
2688                 );
2689
2690                 $dbw->delete(
2691                         'protected_titles',
2692                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2693                         __METHOD__
2694                 );
2695         }
2696
2697         /**
2698          * Does this have subpages?  (Warning, usually requires an extra DB query.)
2699          *
2700          * @return Bool
2701          */
2702         public function hasSubpages() {
2703                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
2704                         # Duh
2705                         return false;
2706                 }
2707
2708                 # We dynamically add a member variable for the purpose of this method
2709                 # alone to cache the result.  There's no point in having it hanging
2710                 # around uninitialized in every Title object; therefore we only add it
2711                 # if needed and don't declare it statically.
2712                 if ( isset( $this->mHasSubpages ) ) {
2713                         return $this->mHasSubpages;
2714                 }
2715
2716                 $subpages = $this->getSubpages( 1 );
2717                 if ( $subpages instanceof TitleArray ) {
2718                         return $this->mHasSubpages = (bool)$subpages->count();
2719                 }
2720                 return $this->mHasSubpages = false;
2721         }
2722
2723         /**
2724          * Get all subpages of this page.
2725          *
2726          * @param $limit Int maximum number of subpages to fetch; -1 for no limit
2727          * @return mixed TitleArray, or empty array if this page's namespace
2728          *  doesn't allow subpages
2729          */
2730         public function getSubpages( $limit = -1 ) {
2731                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
2732                         return array();
2733                 }
2734
2735                 $dbr = wfGetDB( DB_SLAVE );
2736                 $conds['page_namespace'] = $this->getNamespace();
2737                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
2738                 $options = array();
2739                 if ( $limit > -1 ) {
2740                         $options['LIMIT'] = $limit;
2741                 }
2742                 return $this->mSubpages = TitleArray::newFromResult(
2743                         $dbr->select( 'page',
2744                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
2745                                 $conds,
2746                                 __METHOD__,
2747                                 $options
2748                         )
2749                 );
2750         }
2751
2752         /**
2753          * Is there a version of this page in the deletion archive?
2754          *
2755          * @return Int the number of archived revisions
2756          */
2757         public function isDeleted() {
2758                 if ( $this->getNamespace() < 0 ) {
2759                         $n = 0;
2760                 } else {
2761                         $dbr = wfGetDB( DB_SLAVE );
2762
2763                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2764                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2765                                 __METHOD__
2766                         );
2767                         if ( $this->getNamespace() == NS_FILE ) {
2768                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2769                                         array( 'fa_name' => $this->getDBkey() ),
2770                                         __METHOD__
2771                                 );
2772                         }
2773                 }
2774                 return (int)$n;
2775         }
2776
2777         /**
2778          * Is there a version of this page in the deletion archive?
2779          *
2780          * @return Boolean
2781          */
2782         public function isDeletedQuick() {
2783                 if ( $this->getNamespace() < 0 ) {
2784                         return false;
2785                 }
2786                 $dbr = wfGetDB( DB_SLAVE );
2787                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2788                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2789                         __METHOD__
2790                 );
2791                 if ( !$deleted && $this->getNamespace() == NS_FILE ) {
2792                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2793                                 array( 'fa_name' => $this->getDBkey() ),
2794                                 __METHOD__
2795                         );
2796                 }
2797                 return $deleted;
2798         }
2799
2800         /**
2801          * Get the article ID for this Title from the link cache,
2802          * adding it if necessary
2803          *
2804          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select
2805          *  for update
2806          * @return Int the ID
2807          */
2808         public function getArticleID( $flags = 0 ) {
2809                 if ( $this->getNamespace() < 0 ) {
2810                         return $this->mArticleID = 0;
2811                 }
2812                 $linkCache = LinkCache::singleton();
2813                 if ( $flags & self::GAID_FOR_UPDATE ) {
2814                         $oldUpdate = $linkCache->forUpdate( true );
2815                         $linkCache->clearLink( $this );
2816                         $this->mArticleID = $linkCache->addLinkObj( $this );
2817                         $linkCache->forUpdate( $oldUpdate );
2818                 } else {
2819                         if ( -1 == $this->mArticleID ) {
2820                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2821                         }
2822                 }
2823                 return $this->mArticleID;
2824         }
2825
2826         /**
2827          * Is this an article that is a redirect page?
2828          * Uses link cache, adding it if necessary
2829          *
2830          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2831          * @return Bool
2832          */
2833         public function isRedirect( $flags = 0 ) {
2834                 if ( !is_null( $this->mRedirect ) ) {
2835                         return $this->mRedirect;
2836                 }
2837                 # Calling getArticleID() loads the field from cache as needed
2838                 if ( !$this->getArticleID( $flags ) ) {
2839                         return $this->mRedirect = false;
2840                 }
2841
2842                 $linkCache = LinkCache::singleton();
2843                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2844                 if ( $cached === null ) { # check the assumption that the cache actually knows about this title
2845                         # XXX: this does apparently happen, see https://bugzilla.wikimedia.org/show_bug.cgi?id=37209
2846                         #      as a stop gap, perhaps log this, but don't throw an exception?
2847                         throw new MWException( "LinkCache doesn't currently know about this title: " . $this->getPrefixedDBkey() );
2848                 }
2849
2850                 $this->mRedirect = (bool)$cached;
2851
2852                 return $this->mRedirect;
2853         }
2854
2855         /**
2856          * What is the length of this page?
2857          * Uses link cache, adding it if necessary
2858          *
2859          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2860          * @return Int
2861          */
2862         public function getLength( $flags = 0 ) {
2863                 if ( $this->mLength != -1 ) {
2864                         return $this->mLength;
2865                 }
2866                 # Calling getArticleID() loads the field from cache as needed
2867                 if ( !$this->getArticleID( $flags ) ) {
2868                         return $this->mLength = 0;
2869                 }
2870                 $linkCache = LinkCache::singleton();
2871                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'length' );
2872                 if ( $cached === null ) { # check the assumption that the cache actually knows about this title
2873                         # XXX: this does apparently happen, see https://bugzilla.wikimedia.org/show_bug.cgi?id=37209
2874                         #      as a stop gap, perhaps log this, but don't throw an exception?
2875                         throw new MWException( "LinkCache doesn't currently know about this title: " . $this->getPrefixedDBkey() );
2876                 }
2877
2878                 $this->mLength = intval( $cached );
2879
2880                 return $this->mLength;
2881         }
2882
2883         /**
2884          * What is the page_latest field for this page?
2885          *
2886          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2887          * @return Int or 0 if the page doesn't exist
2888          */
2889         public function getLatestRevID( $flags = 0 ) {
2890                 if ( !( $flags & Title::GAID_FOR_UPDATE ) && $this->mLatestID !== false ) {
2891                         return intval( $this->mLatestID );
2892                 }
2893                 # Calling getArticleID() loads the field from cache as needed
2894                 if ( !$this->getArticleID( $flags ) ) {
2895                         return $this->mLatestID = 0;
2896                 }
2897                 $linkCache = LinkCache::singleton();
2898                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'revision' );
2899                 if ( $cached === null ) { # check the assumption that the cache actually knows about this title
2900                         # XXX: this does apparently happen, see https://bugzilla.wikimedia.org/show_bug.cgi?id=37209
2901                         #      as a stop gap, perhaps log this, but don't throw an exception?
2902                         throw new MWException( "LinkCache doesn't currently know about this title: " . $this->getPrefixedDBkey() );
2903                 }
2904
2905                 $this->mLatestID = intval( $cached );
2906
2907                 return $this->mLatestID;
2908         }
2909
2910         /**
2911          * This clears some fields in this object, and clears any associated
2912          * keys in the "bad links" section of the link cache.
2913          *
2914          * - This is called from WikiPage::doEdit() and WikiPage::insertOn() to allow
2915          * loading of the new page_id. It's also called from
2916          * WikiPage::doDeleteArticleReal()
2917          *
2918          * @param $newid Int the new Article ID
2919          */
2920         public function resetArticleID( $newid ) {
2921                 $linkCache = LinkCache::singleton();
2922                 $linkCache->clearLink( $this );
2923
2924                 if ( $newid === false ) {
2925                         $this->mArticleID = -1;
2926                 } else {
2927                         $this->mArticleID = intval( $newid );
2928                 }
2929                 $this->mRestrictionsLoaded = false;
2930                 $this->mRestrictions = array();
2931                 $this->mRedirect = null;
2932                 $this->mLength = -1;
2933                 $this->mLatestID = false;
2934                 $this->mContentModel = false;
2935                 $this->mEstimateRevisions = null;
2936         }
2937
2938         /**
2939          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
2940          *
2941          * @param $text String containing title to capitalize
2942          * @param $ns int namespace index, defaults to NS_MAIN
2943          * @return String containing capitalized title
2944          */
2945         public static function capitalize( $text, $ns = NS_MAIN ) {
2946                 global $wgContLang;
2947
2948                 if ( MWNamespace::isCapitalized( $ns ) ) {
2949                         return $wgContLang->ucfirst( $text );
2950                 } else {
2951                         return $text;
2952                 }
2953         }
2954
2955         /**
2956          * Secure and split - main initialisation function for this object
2957          *
2958          * Assumes that mDbkeyform has been set, and is urldecoded
2959          * and uses underscores, but not otherwise munged.  This function
2960          * removes illegal characters, splits off the interwiki and
2961          * namespace prefixes, sets the other forms, and canonicalizes
2962          * everything.
2963          *
2964          * @return Bool true on success
2965          */
2966         private function secureAndSplit() {
2967                 global $wgContLang, $wgLocalInterwiki;
2968
2969                 # Initialisation
2970                 $this->mInterwiki = $this->mFragment = '';
2971                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2972
2973                 $dbkey = $this->mDbkeyform;
2974
2975                 # Strip Unicode bidi override characters.
2976                 # Sometimes they slip into cut-n-pasted page titles, where the
2977                 # override chars get included in list displays.
2978                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
2979
2980                 # Clean up whitespace
2981                 # Note: use of the /u option on preg_replace here will cause
2982                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
2983                 # conveniently disabling them.
2984                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
2985                 $dbkey = trim( $dbkey, '_' );
2986
2987                 if ( $dbkey == '' ) {
2988                         return false;
2989                 }
2990
2991                 if ( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2992                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2993                         return false;
2994                 }
2995
2996                 $this->mDbkeyform = $dbkey;
2997
2998                 # Initial colon indicates main namespace rather than specified default
2999                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
3000                 if ( ':' == $dbkey[0] ) {
3001                         $this->mNamespace = NS_MAIN;
3002                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
3003                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
3004                 }
3005
3006                 # Namespace or interwiki prefix
3007                 $firstPass = true;
3008                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
3009                 do {
3010                         $m = array();
3011                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
3012                                 $p = $m[1];
3013                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
3014                                         # Ordinary namespace
3015                                         $dbkey = $m[2];
3016                                         $this->mNamespace = $ns;
3017                                         # For Talk:X pages, check if X has a "namespace" prefix
3018                                         if ( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
3019                                                 if ( $wgContLang->getNsIndex( $x[1] ) ) {
3020                                                         # Disallow Talk:File:x type titles...
3021                                                         return false;
3022                                                 } elseif ( Interwiki::isValidInterwiki( $x[1] ) ) {
3023                                                         # Disallow Talk:Interwiki:x type titles...
3024                                                         return false;
3025                                                 }
3026                                         }
3027                                 } elseif ( Interwiki::isValidInterwiki( $p ) ) {
3028                                         if ( !$firstPass ) {
3029                                                 # Can't make a local interwiki link to an interwiki link.
3030                                                 # That's just crazy!
3031                                                 return false;
3032                                         }
3033
3034                                         # Interwiki link
3035                                         $dbkey = $m[2];
3036                                         $this->mInterwiki = $wgContLang->lc( $p );
3037
3038                                         # Redundant interwiki prefix to the local wiki
3039                                         if ( $wgLocalInterwiki !== false
3040                                                 && 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) )
3041                                         {
3042                                                 if ( $dbkey == '' ) {
3043                                                         # Can't have an empty self-link
3044                                                         return false;
3045                                                 }
3046                                                 $this->mInterwiki = '';
3047                                                 $firstPass = false;
3048                                                 # Do another namespace split...
3049                                                 continue;
3050                                         }
3051
3052                                         # If there's an initial colon after the interwiki, that also
3053                                         # resets the default namespace
3054                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
3055                                                 $this->mNamespace = NS_MAIN;
3056                                                 $dbkey = substr( $dbkey, 1 );
3057                                         }
3058                                 }
3059                                 # If there's no recognized interwiki or namespace,
3060                                 # then let the colon expression be part of the title.
3061                         }
3062                         break;
3063                 } while ( true );
3064
3065                 # We already know that some pages won't be in the database!
3066                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
3067                         $this->mArticleID = 0;
3068                 }
3069                 $fragment = strstr( $dbkey, '#' );
3070                 if ( false !== $fragment ) {
3071                         $this->setFragment( $fragment );
3072                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
3073                         # remove whitespace again: prevents "Foo_bar_#"
3074                         # becoming "Foo_bar_"
3075                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
3076                 }
3077
3078                 # Reject illegal characters.
3079                 $rxTc = self::getTitleInvalidRegex();
3080                 if ( preg_match( $rxTc, $dbkey ) ) {
3081                         return false;
3082                 }
3083
3084                 # Pages with "/./" or "/../" appearing in the URLs will often be un-
3085                 # reachable due to the way web browsers deal with 'relative' URLs.
3086                 # Also, they conflict with subpage syntax.  Forbid them explicitly.
3087                 if ( strpos( $dbkey, '.' ) !== false &&
3088                          ( $dbkey === '.' || $dbkey === '..' ||
3089                            strpos( $dbkey, './' ) === 0  ||
3090                            strpos( $dbkey, '../' ) === 0 ||
3091                            strpos( $dbkey, '/./' ) !== false ||
3092                            strpos( $dbkey, '/../' ) !== false  ||
3093                            substr( $dbkey, -2 ) == '/.' ||
3094                            substr( $dbkey, -3 ) == '/..' ) )
3095                 {
3096                         return false;
3097                 }
3098
3099                 # Magic tilde sequences? Nu-uh!
3100                 if ( strpos( $dbkey, '~~~' ) !== false ) {
3101                         return false;
3102                 }
3103
3104                 # Limit the size of titles to 255 bytes. This is typically the size of the
3105                 # underlying database field. We make an exception for special pages, which
3106                 # don't need to be stored in the database, and may edge over 255 bytes due
3107                 # to subpage syntax for long titles, e.g. [[Special:Block/Long name]]
3108                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
3109                   strlen( $dbkey ) > 512 )
3110                 {
3111                         return false;
3112                 }
3113
3114                 # Normally, all wiki links are forced to have an initial capital letter so [[foo]]
3115                 # and [[Foo]] point to the same place.  Don't force it for interwikis, since the
3116                 # other site might be case-sensitive.
3117                 $this->mUserCaseDBKey = $dbkey;
3118                 if ( $this->mInterwiki == '' ) {
3119                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
3120                 }
3121
3122                 # Can't make a link to a namespace alone... "empty" local links can only be
3123                 # self-links with a fragment identifier.
3124                 if ( $dbkey == '' && $this->mInterwiki == '' && $this->mNamespace != NS_MAIN ) {
3125                         return false;
3126                 }
3127
3128                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
3129                 // IP names are not allowed for accounts, and can only be referring to
3130                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
3131                 // there are numerous ways to present the same IP. Having sp:contribs scan
3132                 // them all is silly and having some show the edits and others not is
3133                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
3134                 $dbkey = ( $this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK )
3135                         ? IP::sanitizeIP( $dbkey )
3136                         : $dbkey;
3137
3138                 // Any remaining initial :s are illegal.
3139                 if ( $dbkey !== '' && ':' == $dbkey[0] ) {
3140                         return false;
3141                 }
3142
3143                 # Fill fields
3144                 $this->mDbkeyform = $dbkey;
3145                 $this->mUrlform = wfUrlencode( $dbkey );
3146
3147                 $this->mTextform = str_replace( '_', ' ', $dbkey );
3148
3149                 return true;
3150         }
3151
3152         /**
3153          * Get an array of Title objects linking to this Title
3154          * Also stores the IDs in the link cache.
3155          *
3156          * WARNING: do not use this function on arbitrary user-supplied titles!
3157          * On heavily-used templates it will max out the memory.
3158          *
3159          * @param $options Array: may be FOR UPDATE
3160          * @param $table String: table name
3161          * @param $prefix String: fields prefix
3162          * @return Array of Title objects linking here
3163          */
3164         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3165                 if ( count( $options ) > 0 ) {
3166                         $db = wfGetDB( DB_MASTER );
3167                 } else {
3168                         $db = wfGetDB( DB_SLAVE );
3169                 }
3170
3171                 $res = $db->select(
3172                         array( 'page', $table ),
3173                         self::getSelectFields(),
3174                         array(
3175                                 "{$prefix}_from=page_id",
3176                                 "{$prefix}_namespace" => $this->getNamespace(),
3177                                 "{$prefix}_title"     => $this->getDBkey() ),
3178                         __METHOD__,
3179                         $options
3180                 );
3181
3182                 $retVal = array();
3183                 if ( $res->numRows() ) {
3184                         $linkCache = LinkCache::singleton();
3185                         foreach ( $res as $row ) {
3186                                 $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title );
3187                                 if ( $titleObj ) {
3188                                         $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3189                                         $retVal[] = $titleObj;
3190                                 }
3191                         }
3192                 }
3193                 return $retVal;
3194         }
3195
3196         /**
3197          * Get an array of Title objects using this Title as a template
3198          * Also stores the IDs in the link cache.
3199          *
3200          * WARNING: do not use this function on arbitrary user-supplied titles!
3201          * On heavily-used templates it will max out the memory.
3202          *
3203          * @param $options Array: may be FOR UPDATE
3204          * @return Array of Title the Title objects linking here
3205          */
3206         public function getTemplateLinksTo( $options = array() ) {
3207                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
3208         }
3209
3210         /**
3211          * Get an array of Title objects linked from this Title
3212          * Also stores the IDs in the link cache.
3213          *
3214          * WARNING: do not use this function on arbitrary user-supplied titles!
3215          * On heavily-used templates it will max out the memory.
3216          *
3217          * @param $options Array: may be FOR UPDATE
3218          * @param $table String: table name
3219          * @param $prefix String: fields prefix
3220          * @return Array of Title objects linking here
3221          */
3222         public function getLinksFrom( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3223                 global $wgContentHandlerUseDB;
3224
3225                 $id = $this->getArticleID();
3226
3227                 # If the page doesn't exist; there can't be any link from this page
3228                 if ( !$id ) {
3229                         return array();
3230                 }
3231
3232                 if ( count( $options ) > 0 ) {
3233                         $db = wfGetDB( DB_MASTER );
3234                 } else {
3235                         $db = wfGetDB( DB_SLAVE );
3236                 }
3237
3238                 $namespaceFiled = "{$prefix}_namespace";
3239                 $titleField = "{$prefix}_title";
3240
3241                 $fields = array( $namespaceFiled, $titleField, 'page_id', 'page_len', 'page_is_redirect', 'page_latest' );
3242                 if ( $wgContentHandlerUseDB ) $fields[] = 'page_content_model';
3243
3244                 $res = $db->select(
3245                         array( $table, 'page' ),
3246                         $fields,
3247                         array( "{$prefix}_from" => $id ),
3248                         __METHOD__,
3249                         $options,
3250                         array( 'page' => array( 'LEFT JOIN', array( "page_namespace=$namespaceFiled", "page_title=$titleField" ) ) )
3251                 );
3252
3253                 $retVal = array();
3254                 if ( $res->numRows() ) {
3255                         $linkCache = LinkCache::singleton();
3256                         foreach ( $res as $row ) {
3257                                 $titleObj = Title::makeTitle( $row->$namespaceFiled, $row->$titleField );
3258                                 if ( $titleObj ) {
3259                                         if ( $row->page_id ) {
3260                                                 $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3261                                         } else {
3262                                                 $linkCache->addBadLinkObj( $titleObj );
3263                                         }
3264                                         $retVal[] = $titleObj;
3265                                 }
3266                         }
3267                 }
3268                 return $retVal;
3269         }
3270
3271         /**
3272          * Get an array of Title objects used on this Title as a template
3273          * Also stores the IDs in the link cache.
3274          *
3275          * WARNING: do not use this function on arbitrary user-supplied titles!
3276          * On heavily-used templates it will max out the memory.
3277          *
3278          * @param $options Array: may be FOR UPDATE
3279          * @return Array of Title the Title objects used here
3280          */
3281         public function getTemplateLinksFrom( $options = array() ) {
3282                 return $this->getLinksFrom( $options, 'templatelinks', 'tl' );
3283         }
3284
3285         /**
3286          * Get an array of Title objects referring to non-existent articles linked from this page
3287          *
3288          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
3289          * @return Array of Title the Title objects
3290          */
3291         public function getBrokenLinksFrom() {
3292                 if ( $this->getArticleID() == 0 ) {
3293                         # All links from article ID 0 are false positives
3294                         return array();
3295                 }
3296
3297                 $dbr = wfGetDB( DB_SLAVE );
3298                 $res = $dbr->select(
3299                         array( 'page', 'pagelinks' ),
3300                         array( 'pl_namespace', 'pl_title' ),
3301                         array(
3302                                 'pl_from' => $this->getArticleID(),
3303                                 'page_namespace IS NULL'
3304                         ),
3305                         __METHOD__, array(),
3306                         array(
3307                                 'page' => array(
3308                                         'LEFT JOIN',
3309                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
3310                                 )
3311                         )
3312                 );
3313
3314                 $retVal = array();
3315                 foreach ( $res as $row ) {
3316                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
3317                 }
3318                 return $retVal;
3319         }
3320
3321
3322         /**
3323          * Get a list of URLs to purge from the Squid cache when this
3324          * page changes
3325          *
3326          * @return Array of String the URLs
3327          */
3328         public function getSquidURLs() {
3329                 $urls = array(
3330                         $this->getInternalURL(),
3331                         $this->getInternalURL( 'action=history' )
3332                 );
3333
3334                 $pageLang = $this->getPageLanguage();
3335                 if ( $pageLang->hasVariants() ) {
3336                         $variants = $pageLang->getVariants();
3337                         foreach ( $variants as $vCode ) {
3338                                 $urls[] = $this->getInternalURL( '', $vCode );
3339                         }
3340                 }
3341
3342                 return $urls;
3343         }
3344
3345         /**
3346          * Purge all applicable Squid URLs
3347          */
3348         public function purgeSquid() {
3349                 global $wgUseSquid;
3350                 if ( $wgUseSquid ) {
3351                         $urls = $this->getSquidURLs();
3352                         $u = new SquidUpdate( $urls );
3353                         $u->doUpdate();
3354                 }
3355         }
3356
3357         /**
3358          * Move this page without authentication
3359          *
3360          * @param $nt Title the new page Title
3361          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3362          */
3363         public function moveNoAuth( &$nt ) {
3364                 return $this->moveTo( $nt, false );
3365         }
3366
3367         /**
3368          * Check whether a given move operation would be valid.
3369          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
3370          *
3371          * @param $nt Title the new title
3372          * @param $auth Bool indicates whether $wgUser's permissions
3373          *  should be checked
3374          * @param $reason String is the log summary of the move, used for spam checking
3375          * @return Mixed True on success, getUserPermissionsErrors()-like array on failure
3376          */
3377         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
3378                 global $wgUser;
3379
3380                 $errors = array();
3381                 if ( !$nt ) {
3382                         // Normally we'd add this to $errors, but we'll get
3383                         // lots of syntax errors if $nt is not an object
3384                         return array( array( 'badtitletext' ) );
3385                 }
3386                 if ( $this->equals( $nt ) ) {
3387                         $errors[] = array( 'selfmove' );
3388                 }
3389                 if ( !$this->isMovable() ) {
3390                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
3391                 }
3392                 if ( $nt->getInterwiki() != '' ) {
3393                         $errors[] = array( 'immobile-target-namespace-iw' );
3394                 }
3395                 if ( !$nt->isMovable() ) {
3396                         $errors[] = array( 'immobile-target-namespace', $nt->getNsText() );
3397                 }
3398
3399                 $oldid = $this->getArticleID();
3400                 $newid = $nt->getArticleID();
3401
3402                 if ( strlen( $nt->getDBkey() ) < 1 ) {
3403                         $errors[] = array( 'articleexists' );
3404                 }
3405                 if ( ( $this->getDBkey() == '' ) ||
3406                          ( !$oldid ) ||
3407                          ( $nt->getDBkey() == '' ) ) {
3408                         $errors[] = array( 'badarticleerror' );
3409                 }
3410
3411                 // Image-specific checks
3412                 if ( $this->getNamespace() == NS_FILE ) {
3413                         $errors = array_merge( $errors, $this->validateFileMoveOperation( $nt ) );
3414                 }
3415
3416                 if ( $nt->getNamespace() == NS_FILE && $this->getNamespace() != NS_FILE ) {
3417                         $errors[] = array( 'nonfile-cannot-move-to-file' );
3418                 }
3419
3420                 if ( $auth ) {
3421                         $errors = wfMergeErrorArrays( $errors,
3422                                 $this->getUserPermissionsErrors( 'move', $wgUser ),
3423                                 $this->getUserPermissionsErrors( 'edit', $wgUser ),
3424                                 $nt->getUserPermissionsErrors( 'move-target', $wgUser ),
3425                                 $nt->getUserPermissionsErrors( 'edit', $wgUser ) );
3426                 }
3427
3428                 $match = EditPage::matchSummarySpamRegex( $reason );
3429                 if ( $match !== false ) {
3430                         // This is kind of lame, won't display nice
3431                         $errors[] = array( 'spamprotectiontext' );
3432                 }
3433
3434                 $err = null;
3435                 if ( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
3436                         $errors[] = array( 'hookaborted', $err );
3437                 }
3438
3439                 # The move is allowed only if (1) the target doesn't exist, or
3440                 # (2) the target is a redirect to the source, and has no history
3441                 # (so we can undo bad moves right after they're done).
3442
3443                 if ( 0 != $newid ) { # Target exists; check for validity
3444                         if ( !$this->isValidMoveTarget( $nt ) ) {
3445                                 $errors[] = array( 'articleexists' );
3446                         }
3447                 } else {
3448                         $tp = $nt->getTitleProtection();
3449                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
3450                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
3451                                 $errors[] = array( 'cantmove-titleprotected' );
3452                         }
3453                 }
3454                 if ( empty( $errors ) ) {
3455                         return true;
3456                 }
3457                 return $errors;
3458         }
3459
3460         /**
3461          * Check if the requested move target is a valid file move target
3462          * @param Title $nt Target title
3463          * @return array List of errors
3464          */
3465         protected function validateFileMoveOperation( $nt ) {
3466                 global $wgUser;
3467
3468                 $errors = array();
3469
3470                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is not allowed until below
3471
3472                 $file = wfLocalFile( $this );
3473                 if ( $file->exists() ) {
3474                         if ( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
3475                                 $errors[] = array( 'imageinvalidfilename' );
3476                         }
3477                         if ( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
3478                                 $errors[] = array( 'imagetypemismatch' );
3479                         }
3480                 }
3481
3482                 if ( $nt->getNamespace() != NS_FILE ) {
3483                         $errors[] = array( 'imagenocrossnamespace' );
3484                         // From here we want to do checks on a file object, so if we can't
3485                         // create one, we must return.
3486                         return $errors;
3487                 }
3488
3489                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is allowed below here
3490
3491                 $destFile = wfLocalFile( $nt );
3492                 if ( !$wgUser->isAllowed( 'reupload-shared' ) && !$destFile->exists() && wfFindFile( $nt ) ) {
3493                         $errors[] = array( 'file-exists-sharedrepo' );
3494                 }
3495
3496                 return $errors;
3497         }
3498
3499         /**
3500          * Move a title to a new location
3501          *
3502          * @param $nt Title the new title
3503          * @param $auth Bool indicates whether $wgUser's permissions
3504          *  should be checked
3505          * @param $reason String the reason for the move
3506          * @param $createRedirect Bool Whether to create a redirect from the old title to the new title.
3507          *  Ignored if the user doesn't have the suppressredirect right.
3508          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3509          */
3510         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
3511                 global $wgUser;
3512                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
3513                 if ( is_array( $err ) ) {
3514                         // Auto-block user's IP if the account was "hard" blocked
3515                         $wgUser->spreadAnyEditBlock();
3516                         return $err;
3517                 }
3518                 // Check suppressredirect permission
3519                 if ( $auth && !$wgUser->isAllowed( 'suppressredirect' ) ) {
3520                         $createRedirect = true;
3521                 }
3522
3523                 // If it is a file, move it first.
3524                 // It is done before all other moving stuff is done because it's hard to revert.
3525                 $dbw = wfGetDB( DB_MASTER );
3526                 if ( $this->getNamespace() == NS_FILE ) {
3527                         $file = wfLocalFile( $this );
3528                         if ( $file->exists() ) {
3529                                 $status = $file->move( $nt );
3530                                 if ( !$status->isOk() ) {
3531                                         return $status->getErrorsArray();
3532                                 }
3533                         }
3534                         // Clear RepoGroup process cache
3535                         RepoGroup::singleton()->clearCache( $this );
3536                         RepoGroup::singleton()->clearCache( $nt ); # clear false negative cache
3537                 }
3538
3539                 $dbw->begin( __METHOD__ ); # If $file was a LocalFile, its transaction would have closed our own.
3540                 $pageid = $this->getArticleID( self::GAID_FOR_UPDATE );
3541                 $protected = $this->isProtected();
3542
3543                 // Do the actual move
3544                 $this->moveToInternal( $nt, $reason, $createRedirect );
3545
3546                 // Refresh the sortkey for this row.  Be careful to avoid resetting
3547                 // cl_timestamp, which may disturb time-based lists on some sites.
3548                 $prefixes = $dbw->select(
3549                         'categorylinks',
3550                         array( 'cl_sortkey_prefix', 'cl_to' ),
3551                         array( 'cl_from' => $pageid ),
3552                         __METHOD__
3553                 );
3554                 foreach ( $prefixes as $prefixRow ) {
3555                         $prefix = $prefixRow->cl_sortkey_prefix;
3556                         $catTo = $prefixRow->cl_to;
3557                         $dbw->update( 'categorylinks',
3558                                 array(
3559                                         'cl_sortkey' => Collation::singleton()->getSortKey(
3560                                                 $nt->getCategorySortkey( $prefix ) ),
3561                                         'cl_timestamp=cl_timestamp' ),
3562                                 array(
3563                                         'cl_from' => $pageid,
3564                                         'cl_to' => $catTo ),
3565                                 __METHOD__
3566                         );
3567                 }
3568
3569                 $redirid = $this->getArticleID();
3570
3571                 if ( $protected ) {
3572                         # Protect the redirect title as the title used to be...
3573                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
3574                                 array(
3575                                         'pr_page'    => $redirid,
3576                                         'pr_type'    => 'pr_type',
3577                                         'pr_level'   => 'pr_level',
3578                                         'pr_cascade' => 'pr_cascade',
3579                                         'pr_user'    => 'pr_user',
3580                                         'pr_expiry'  => 'pr_expiry'
3581                                 ),
3582                                 array( 'pr_page' => $pageid ),
3583                                 __METHOD__,
3584                                 array( 'IGNORE' )
3585                         );
3586                         # Update the protection log
3587                         $log = new LogPage( 'protect' );
3588                         $comment = wfMessage(
3589                                 'prot_1movedto2',
3590                                 $this->getPrefixedText(),
3591                                 $nt->getPrefixedText()
3592                         )->inContentLanguage()->text();
3593                         if ( $reason ) {
3594                                 $comment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
3595                         }
3596                         // @todo FIXME: $params?
3597                         $log->addEntry( 'move_prot', $nt, $comment, array( $this->getPrefixedText() ) );
3598                 }
3599
3600                 # Update watchlists
3601                 $oldnamespace = $this->getNamespace() & ~1;
3602                 $newnamespace = $nt->getNamespace() & ~1;
3603                 $oldtitle = $this->getDBkey();
3604                 $newtitle = $nt->getDBkey();
3605
3606                 if ( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
3607                         WatchedItem::duplicateEntries( $this, $nt );
3608                 }
3609
3610                 $dbw->commit( __METHOD__ );
3611
3612                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3613                 return true;
3614         }
3615
3616         /**
3617          * Move page to a title which is either a redirect to the
3618          * source page or nonexistent
3619          *
3620          * @param $nt Title the page to move to, which should be a redirect or nonexistent
3621          * @param $reason String The reason for the move
3622          * @param $createRedirect Bool Whether to leave a redirect at the old title. Does not check
3623          *   if the user has the suppressredirect right
3624          * @throws MWException
3625          */
3626         private function moveToInternal( &$nt, $reason = '', $createRedirect = true ) {
3627                 global $wgUser, $wgContLang;
3628
3629                 if ( $nt->exists() ) {
3630                         $moveOverRedirect = true;
3631                         $logType = 'move_redir';
3632                 } else {
3633                         $moveOverRedirect = false;
3634                         $logType = 'move';
3635                 }
3636
3637                 $redirectSuppressed = !$createRedirect;
3638
3639                 $logEntry = new ManualLogEntry( 'move', $logType );
3640                 $logEntry->setPerformer( $wgUser );
3641                 $logEntry->setTarget( $this );
3642                 $logEntry->setComment( $reason );
3643                 $logEntry->setParameters( array(
3644                         '4::target' => $nt->getPrefixedText(),
3645                         '5::noredir' => $redirectSuppressed ? '1': '0',
3646                 ) );
3647
3648                 $formatter = LogFormatter::newFromEntry( $logEntry );
3649                 $formatter->setContext( RequestContext::newExtraneousContext( $this ) );
3650                 $comment = $formatter->getPlainActionText();
3651                 if ( $reason ) {
3652                         $comment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
3653                 }
3654                 # Truncate for whole multibyte characters.
3655                 $comment = $wgContLang->truncate( $comment, 255 );
3656
3657                 $oldid = $this->getArticleID();
3658
3659                 $dbw = wfGetDB( DB_MASTER );
3660
3661                 $newpage = WikiPage::factory( $nt );
3662
3663                 if ( $moveOverRedirect ) {
3664                         $newid = $nt->getArticleID();
3665
3666                         # Delete the old redirect. We don't save it to history since
3667                         # by definition if we've got here it's rather uninteresting.
3668                         # We have to remove it so that the next step doesn't trigger
3669                         # a conflict on the unique namespace+title index...
3670                         $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3671
3672                         $newpage->doDeleteUpdates( $newid );
3673                 }
3674
3675                 # Save a null revision in the page's history notifying of the move
3676                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3677                 if ( !is_object( $nullRevision ) ) {
3678                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3679                 }
3680                 $nullRevId = $nullRevision->insertOn( $dbw );
3681
3682                 # Change the name of the target page:
3683                 $dbw->update( 'page',
3684                         /* SET */ array(
3685                                 'page_namespace' => $nt->getNamespace(),
3686                                 'page_title'     => $nt->getDBkey(),
3687                         ),
3688                         /* WHERE */ array( 'page_id' => $oldid ),
3689                         __METHOD__
3690                 );
3691
3692                 $this->resetArticleID( 0 );
3693                 $nt->resetArticleID( $oldid );
3694
3695                 $newpage->updateRevisionOn( $dbw, $nullRevision );
3696
3697                 wfRunHooks( 'NewRevisionFromEditComplete',
3698                         array( $newpage, $nullRevision, $nullRevision->getParentId(), $wgUser ) );
3699
3700                 $newpage->doEditUpdates( $nullRevision, $wgUser, array( 'changed' => false ) );
3701
3702                 if ( !$moveOverRedirect ) {
3703                         WikiPage::onArticleCreate( $nt );
3704                 }
3705
3706                 # Recreate the redirect, this time in the other direction.
3707                 if ( $redirectSuppressed ) {
3708                         WikiPage::onArticleDelete( $this );
3709                 } else {
3710                         $mwRedir = MagicWord::get( 'redirect' );
3711                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3712                         $redirectArticle = WikiPage::factory( $this );
3713                         $newid = $redirectArticle->insertOn( $dbw );
3714                         if ( $newid ) { // sanity
3715                                 $redirectRevision = new Revision( array(
3716                                         'page'    => $newid,
3717                                         'comment' => $comment,
3718                                         'text'    => $redirectText ) );
3719                                 $redirectRevision->insertOn( $dbw );
3720                                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3721
3722                                 wfRunHooks( 'NewRevisionFromEditComplete',
3723                                         array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3724
3725                                 $redirectArticle->doEditUpdates( $redirectRevision, $wgUser, array( 'created' => true ) );
3726                         }
3727                 }
3728
3729                 # Log the move
3730                 $logid = $logEntry->insert();
3731                 $logEntry->publish( $logid );
3732         }
3733
3734         /**
3735          * Move this page's subpages to be subpages of $nt
3736          *
3737          * @param $nt Title Move target
3738          * @param $auth bool Whether $wgUser's permissions should be checked
3739          * @param $reason string The reason for the move
3740          * @param $createRedirect bool Whether to create redirects from the old subpages to
3741          *     the new ones Ignored if the user doesn't have the 'suppressredirect' right
3742          * @return mixed array with old page titles as keys, and strings (new page titles) or
3743          *     arrays (errors) as values, or an error array with numeric indices if no pages
3744          *     were moved
3745          */
3746         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3747                 global $wgMaximumMovedPages;
3748                 // Check permissions
3749                 if ( !$this->userCan( 'move-subpages' ) ) {
3750                         return array( 'cant-move-subpages' );
3751                 }
3752                 // Do the source and target namespaces support subpages?
3753                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
3754                         return array( 'namespace-nosubpages',
3755                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3756                 }
3757                 if ( !MWNamespace::hasSubpages( $nt->getNamespace() ) ) {
3758                         return array( 'namespace-nosubpages',
3759                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3760                 }
3761
3762                 $subpages = $this->getSubpages( $wgMaximumMovedPages + 1 );
3763                 $retval = array();
3764                 $count = 0;
3765                 foreach ( $subpages as $oldSubpage ) {
3766                         $count++;
3767                         if ( $count > $wgMaximumMovedPages ) {
3768                                 $retval[$oldSubpage->getPrefixedTitle()] =
3769                                                 array( 'movepage-max-pages',
3770                                                         $wgMaximumMovedPages );
3771                                 break;
3772                         }
3773
3774                         // We don't know whether this function was called before
3775                         // or after moving the root page, so check both
3776                         // $this and $nt
3777                         if ( $oldSubpage->getArticleID() == $this->getArticleID() ||
3778                                         $oldSubpage->getArticleID() == $nt->getArticleID() )
3779                         {
3780                                 // When moving a page to a subpage of itself,
3781                                 // don't move it twice
3782                                 continue;
3783                         }
3784                         $newPageName = preg_replace(
3785                                         '#^' . preg_quote( $this->getDBkey(), '#' ) . '#',
3786                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3787                                         $oldSubpage->getDBkey() );
3788                         if ( $oldSubpage->isTalkPage() ) {
3789                                 $newNs = $nt->getTalkPage()->getNamespace();
3790                         } else {
3791                                 $newNs = $nt->getSubjectPage()->getNamespace();
3792                         }
3793                         # Bug 14385: we need makeTitleSafe because the new page names may
3794                         # be longer than 255 characters.
3795                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3796
3797                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3798                         if ( $success === true ) {
3799                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3800                         } else {
3801                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3802                         }
3803                 }
3804                 return $retval;
3805         }
3806
3807         /**
3808          * Checks if this page is just a one-rev redirect.
3809          * Adds lock, so don't use just for light purposes.
3810          *
3811          * @return Bool
3812          */
3813         public function isSingleRevRedirect() {
3814                 global $wgContentHandlerUseDB;
3815
3816                 $dbw = wfGetDB( DB_MASTER );
3817
3818                 # Is it a redirect?
3819                 $fields = array( 'page_is_redirect', 'page_latest', 'page_id' );
3820                 if ( $wgContentHandlerUseDB ) $fields[] = 'page_content_model';
3821
3822                 $row = $dbw->selectRow( 'page',
3823                         $fields,
3824                         $this->pageCond(),
3825                         __METHOD__,
3826                         array( 'FOR UPDATE' )
3827                 );
3828                 # Cache some fields we may want
3829                 $this->mArticleID = $row ? intval( $row->page_id ) : 0;
3830                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3831                 $this->mLatestID = $row ? intval( $row->page_latest ) : false;
3832                 $this->mContentModel = $row && isset( $row->page_content_model ) ? strval( $row->page_content_model ) : false;
3833                 if ( !$this->mRedirect ) {
3834                         return false;
3835                 }
3836                 # Does the article have a history?
3837                 $row = $dbw->selectField( array( 'page', 'revision' ),
3838                         'rev_id',
3839                         array( 'page_namespace' => $this->getNamespace(),
3840                                 'page_title' => $this->getDBkey(),
3841                                 'page_id=rev_page',
3842                                 'page_latest != rev_id'
3843                         ),
3844                         __METHOD__,
3845                         array( 'FOR UPDATE' )
3846                 );
3847                 # Return true if there was no history
3848                 return ( $row === false );
3849         }
3850
3851         /**
3852          * Checks if $this can be moved to a given Title
3853          * - Selects for update, so don't call it unless you mean business
3854          *
3855          * @param $nt Title the new title to check
3856          * @return Bool
3857          */
3858         public function isValidMoveTarget( $nt ) {
3859                 # Is it an existing file?
3860                 if ( $nt->getNamespace() == NS_FILE ) {
3861                         $file = wfLocalFile( $nt );
3862                         if ( $file->exists() ) {
3863                                 wfDebug( __METHOD__ . ": file exists\n" );
3864                                 return false;
3865                         }
3866                 }
3867                 # Is it a redirect with no history?
3868                 if ( !$nt->isSingleRevRedirect() ) {
3869                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3870                         return false;
3871                 }
3872                 # Get the article text
3873                 $rev = Revision::newFromTitle( $nt, false, Revision::READ_LATEST );
3874                 if( !is_object( $rev ) ){
3875                         return false;
3876                 }
3877                 $content = $rev->getContent();
3878                 # Does the redirect point to the source?
3879                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3880                 $redirTitle = $content->getRedirectTarget();
3881
3882                 if ( $redirTitle ) {
3883                         if ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3884                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) {
3885                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3886                                 return false;
3887                         } else {
3888                                 return true;
3889                         }
3890                 } else {
3891                         # Fail safe (not a redirect after all. strange.)
3892                         wfDebug( __METHOD__ . ": failsafe: database sais " . $nt->getPrefixedDBkey() .
3893                                                 " is a redirect, but it doesn't contain a valid redirect.\n" );
3894                         return false;
3895                 }
3896         }
3897
3898         /**
3899          * Get categories to which this Title belongs and return an array of
3900          * categories' names.
3901          *
3902          * @return Array of parents in the form:
3903          *        $parent => $currentarticle
3904          */
3905         public function getParentCategories() {
3906                 global $wgContLang;
3907
3908                 $data = array();
3909
3910                 $titleKey = $this->getArticleID();
3911
3912                 if ( $titleKey === 0 ) {
3913                         return $data;
3914                 }
3915
3916                 $dbr = wfGetDB( DB_SLAVE );
3917
3918                 $res = $dbr->select( 'categorylinks', '*',
3919                         array(
3920                                 'cl_from' => $titleKey,
3921                         ),
3922                         __METHOD__,
3923                         array()
3924                 );
3925
3926                 if ( $dbr->numRows( $res ) > 0 ) {
3927                         foreach ( $res as $row ) {
3928                                 // $data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
3929                                 $data[$wgContLang->getNSText( NS_CATEGORY ) . ':' . $row->cl_to] = $this->getFullText();
3930                         }
3931                 }
3932                 return $data;
3933         }
3934
3935         /**
3936          * Get a tree of parent categories
3937          *
3938          * @param $children Array with the children in the keys, to check for circular refs
3939          * @return Array Tree of parent categories
3940          */
3941         public function getParentCategoryTree( $children = array() ) {
3942                 $stack = array();
3943                 $parents = $this->getParentCategories();
3944
3945                 if ( $parents ) {
3946                         foreach ( $parents as $parent => $current ) {
3947                                 if ( array_key_exists( $parent, $children ) ) {
3948                                         # Circular reference
3949                                         $stack[$parent] = array();
3950                                 } else {
3951                                         $nt = Title::newFromText( $parent );
3952                                         if ( $nt ) {
3953                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array( $parent => 1 ) );
3954                                         }
3955                                 }
3956                         }
3957                 }
3958
3959                 return $stack;
3960         }
3961
3962         /**
3963          * Get an associative array for selecting this title from
3964          * the "page" table
3965          *
3966          * @return Array suitable for the $where parameter of DB::select()
3967          */
3968         public function pageCond() {
3969                 if ( $this->mArticleID > 0 ) {
3970                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
3971                         return array( 'page_id' => $this->mArticleID );
3972                 } else {
3973                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
3974                 }
3975         }
3976
3977         /**
3978          * Get the revision ID of the previous revision
3979          *
3980          * @param $revId Int Revision ID. Get the revision that was before this one.
3981          * @param $flags Int Title::GAID_FOR_UPDATE
3982          * @return Int|Bool Old revision ID, or FALSE if none exists
3983          */
3984         public function getPreviousRevisionID( $revId, $flags = 0 ) {
3985                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3986                 $revId = $db->selectField( 'revision', 'rev_id',
3987                         array(
3988                                 'rev_page' => $this->getArticleID( $flags ),
3989                                 'rev_id < ' . intval( $revId )
3990                         ),
3991                         __METHOD__,
3992                         array( 'ORDER BY' => 'rev_id DESC' )
3993                 );
3994
3995                 if ( $revId === false ) {
3996                         return false;
3997                 } else {
3998                         return intval( $revId );
3999                 }
4000         }
4001
4002         /**
4003          * Get the revision ID of the next revision
4004          *
4005          * @param $revId Int Revision ID. Get the revision that was after this one.
4006          * @param $flags Int Title::GAID_FOR_UPDATE
4007          * @return Int|Bool Next revision ID, or FALSE if none exists
4008          */
4009         public function getNextRevisionID( $revId, $flags = 0 ) {
4010                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4011                 $revId = $db->selectField( 'revision', 'rev_id',
4012                         array(
4013                                 'rev_page' => $this->getArticleID( $flags ),
4014                                 'rev_id > ' . intval( $revId )
4015                         ),
4016                         __METHOD__,
4017                         array( 'ORDER BY' => 'rev_id' )
4018                 );
4019
4020                 if ( $revId === false ) {
4021                         return false;
4022                 } else {
4023                         return intval( $revId );
4024                 }
4025         }
4026
4027         /**
4028          * Get the first revision of the page
4029          *
4030          * @param $flags Int Title::GAID_FOR_UPDATE
4031          * @return Revision|Null if page doesn't exist
4032          */
4033         public function getFirstRevision( $flags = 0 ) {
4034                 $pageId = $this->getArticleID( $flags );
4035                 if ( $pageId ) {
4036                         $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4037                         $row = $db->selectRow( 'revision', Revision::selectFields(),
4038                                 array( 'rev_page' => $pageId ),
4039                                 __METHOD__,
4040                                 array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
4041                         );
4042                         if ( $row ) {
4043                                 return new Revision( $row );
4044                         }
4045                 }
4046                 return null;
4047         }
4048
4049         /**
4050          * Get the oldest revision timestamp of this page
4051          *
4052          * @param $flags Int Title::GAID_FOR_UPDATE
4053          * @return String: MW timestamp
4054          */
4055         public function getEarliestRevTime( $flags = 0 ) {
4056                 $rev = $this->getFirstRevision( $flags );
4057                 return $rev ? $rev->getTimestamp() : null;
4058         }
4059
4060         /**
4061          * Check if this is a new page
4062          *
4063          * @return bool
4064          */
4065         public function isNewPage() {
4066                 $dbr = wfGetDB( DB_SLAVE );
4067                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
4068         }
4069
4070         /**
4071          * Check whether the number of revisions of this page surpasses $wgDeleteRevisionsLimit
4072          *
4073          * @return bool
4074          */
4075         public function isBigDeletion() {
4076                 global $wgDeleteRevisionsLimit;
4077
4078                 if ( !$wgDeleteRevisionsLimit ) {
4079                         return false;
4080                 }
4081
4082                 $revCount = $this->estimateRevisionCount();
4083                 return $revCount > $wgDeleteRevisionsLimit;
4084         }
4085
4086         /**
4087          * Get the  approximate revision count of this page.
4088          *
4089          * @return int
4090          */
4091         public function estimateRevisionCount() {
4092                 if ( !$this->exists() ) {
4093                         return 0;
4094                 }
4095
4096                 if ( $this->mEstimateRevisions === null ) {
4097                         $dbr = wfGetDB( DB_SLAVE );
4098                         $this->mEstimateRevisions = $dbr->estimateRowCount( 'revision', '*',
4099                                 array( 'rev_page' => $this->getArticleID() ), __METHOD__ );
4100                 }
4101
4102                 return $this->mEstimateRevisions;
4103         }
4104
4105         /**
4106          * Get the number of revisions between the given revision.
4107          * Used for diffs and other things that really need it.
4108          *
4109          * @param $old int|Revision Old revision or rev ID (first before range)
4110          * @param $new int|Revision New revision or rev ID (first after range)
4111          * @return Int Number of revisions between these revisions.
4112          */
4113         public function countRevisionsBetween( $old, $new ) {
4114                 if ( !( $old instanceof Revision ) ) {
4115                         $old = Revision::newFromTitle( $this, (int)$old );
4116                 }
4117                 if ( !( $new instanceof Revision ) ) {
4118                         $new = Revision::newFromTitle( $this, (int)$new );
4119                 }
4120                 if ( !$old || !$new ) {
4121                         return 0; // nothing to compare
4122                 }
4123                 $dbr = wfGetDB( DB_SLAVE );
4124                 return (int)$dbr->selectField( 'revision', 'count(*)',
4125                         array(
4126                                 'rev_page' => $this->getArticleID(),
4127                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4128                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4129                         ),
4130                         __METHOD__
4131                 );
4132         }
4133
4134         /**
4135          * Get the number of authors between the given revisions or revision IDs.
4136          * Used for diffs and other things that really need it.
4137          *
4138          * @param $old int|Revision Old revision or rev ID (first before range by default)
4139          * @param $new int|Revision New revision or rev ID (first after range by default)
4140          * @param $limit int Maximum number of authors
4141          * @param $options string|array (Optional): Single option, or an array of options:
4142          *     'include_old' Include $old in the range; $new is excluded.
4143          *     'include_new' Include $new in the range; $old is excluded.
4144          *     'include_both' Include both $old and $new in the range.
4145          *     Unknown option values are ignored.
4146          * @return int Number of revision authors in the range; zero if not both revisions exist
4147          */
4148         public function countAuthorsBetween( $old, $new, $limit, $options = array() ) {
4149                 if ( !( $old instanceof Revision ) ) {
4150                         $old = Revision::newFromTitle( $this, (int)$old );
4151                 }
4152                 if ( !( $new instanceof Revision ) ) {
4153                         $new = Revision::newFromTitle( $this, (int)$new );
4154                 }
4155                 // XXX: what if Revision objects are passed in, but they don't refer to this title?
4156                 // Add $old->getPage() != $new->getPage() || $old->getPage() != $this->getArticleID()
4157                 // in the sanity check below?
4158                 if ( !$old || !$new ) {
4159                         return 0; // nothing to compare
4160                 }
4161                 $old_cmp = '>';
4162                 $new_cmp = '<';
4163                 $options = (array) $options;
4164                 if ( in_array( 'include_old', $options ) ) {
4165                         $old_cmp = '>=';
4166                 }
4167                 if ( in_array( 'include_new', $options ) ) {
4168                         $new_cmp = '<=';
4169                 }
4170                 if ( in_array( 'include_both', $options ) ) {
4171                         $old_cmp = '>=';
4172                         $new_cmp = '<=';
4173                 }
4174                 // No DB query needed if $old and $new are the same or successive revisions:
4175                 if ( $old->getId() === $new->getId() ) {
4176                         return ( $old_cmp === '>' && $new_cmp === '<' ) ? 0 : 1;
4177                 } else if ( $old->getId() === $new->getParentId() ) {
4178                         if ( $old_cmp === '>' || $new_cmp === '<' ) {
4179                                 return ( $old_cmp === '>' && $new_cmp === '<' ) ? 0 : 1;
4180                         }
4181                         return ( $old->getRawUserText() === $new->getRawUserText() ) ? 1 : 2;
4182                 }
4183                 $dbr = wfGetDB( DB_SLAVE );
4184                 $res = $dbr->select( 'revision', 'DISTINCT rev_user_text',
4185                         array(
4186                                 'rev_page' => $this->getArticleID(),
4187                                 "rev_timestamp $old_cmp " . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4188                                 "rev_timestamp $new_cmp " . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4189                         ), __METHOD__,
4190                         array( 'LIMIT' => $limit + 1 ) // add one so caller knows it was truncated
4191                 );
4192                 return (int)$dbr->numRows( $res );
4193         }
4194
4195         /**
4196          * Compare with another title.
4197          *
4198          * @param $title Title
4199          * @return Bool
4200          */
4201         public function equals( Title $title ) {
4202                 // Note: === is necessary for proper matching of number-like titles.
4203                 return $this->getInterwiki() === $title->getInterwiki()
4204                         && $this->getNamespace() == $title->getNamespace()
4205                         && $this->getDBkey() === $title->getDBkey();
4206         }
4207
4208         /**
4209          * Check if this title is a subpage of another title
4210          *
4211          * @param $title Title
4212          * @return Bool
4213          */
4214         public function isSubpageOf( Title $title ) {
4215                 return $this->getInterwiki() === $title->getInterwiki()
4216                         && $this->getNamespace() == $title->getNamespace()
4217                         && strpos( $this->getDBkey(), $title->getDBkey() . '/' ) === 0;
4218         }
4219
4220         /**
4221          * Check if page exists.  For historical reasons, this function simply
4222          * checks for the existence of the title in the page table, and will
4223          * thus return false for interwiki links, special pages and the like.
4224          * If you want to know if a title can be meaningfully viewed, you should
4225          * probably call the isKnown() method instead.
4226          *
4227          * @return Bool
4228          */
4229         public function exists() {
4230                 return $this->getArticleID() != 0;
4231         }
4232
4233         /**
4234          * Should links to this title be shown as potentially viewable (i.e. as
4235          * "bluelinks"), even if there's no record by this title in the page
4236          * table?
4237          *
4238          * This function is semi-deprecated for public use, as well as somewhat
4239          * misleadingly named.  You probably just want to call isKnown(), which
4240          * calls this function internally.
4241          *
4242          * (ISSUE: Most of these checks are cheap, but the file existence check
4243          * can potentially be quite expensive.  Including it here fixes a lot of
4244          * existing code, but we might want to add an optional parameter to skip
4245          * it and any other expensive checks.)
4246          *
4247          * @return Bool
4248          */
4249         public function isAlwaysKnown() {
4250                 $isKnown = null;
4251
4252                 /**
4253                  * Allows overriding default behaviour for determining if a page exists.
4254                  * If $isKnown is kept as null, regular checks happen. If it's
4255                  * a boolean, this value is returned by the isKnown method.
4256                  *
4257                  * @since 1.20
4258                  *
4259                  * @param Title $title
4260                  * @param boolean|null $isKnown
4261                  */
4262                 wfRunHooks( 'TitleIsAlwaysKnown', array( $this, &$isKnown ) );
4263
4264                 if ( !is_null( $isKnown ) ) {
4265                         return $isKnown;
4266                 }
4267
4268                 if ( $this->mInterwiki != '' ) {
4269                         return true;  // any interwiki link might be viewable, for all we know
4270                 }
4271
4272                 switch( $this->mNamespace ) {
4273                         case NS_MEDIA:
4274                         case NS_FILE:
4275                                 // file exists, possibly in a foreign repo
4276                                 return (bool)wfFindFile( $this );
4277                         case NS_SPECIAL:
4278                                 // valid special page
4279                                 return SpecialPageFactory::exists( $this->getDBkey() );
4280                         case NS_MAIN:
4281                                 // selflink, possibly with fragment
4282                                 return $this->mDbkeyform == '';
4283                         case NS_MEDIAWIKI:
4284                                 // known system message
4285                                 return $this->hasSourceText() !== false;
4286                         default:
4287                                 return false;
4288                 }
4289         }
4290
4291         /**
4292          * Does this title refer to a page that can (or might) be meaningfully
4293          * viewed?  In particular, this function may be used to determine if
4294          * links to the title should be rendered as "bluelinks" (as opposed to
4295          * "redlinks" to non-existent pages).
4296          * Adding something else to this function will cause inconsistency
4297          * since LinkHolderArray calls isAlwaysKnown() and does its own
4298          * page existence check.
4299          *
4300          * @return Bool
4301          */
4302         public function isKnown() {
4303                 return $this->isAlwaysKnown() || $this->exists();
4304         }
4305
4306         /**
4307          * Does this page have source text?
4308          *
4309          * @return Boolean
4310          */
4311         public function hasSourceText() {
4312                 if ( $this->exists() ) {
4313                         return true;
4314                 }
4315
4316                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
4317                         // If the page doesn't exist but is a known system message, default
4318                         // message content will be displayed, same for language subpages-
4319                         // Use always content language to avoid loading hundreds of languages
4320                         // to get the link color.
4321                         global $wgContLang;
4322                         list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4323                         $message = wfMessage( $name )->inLanguage( $wgContLang )->useDatabase( false );
4324                         return $message->exists();
4325                 }
4326
4327                 return false;
4328         }
4329
4330         /**
4331          * Get the default message text or false if the message doesn't exist
4332          *
4333          * @return String or false
4334          */
4335         public function getDefaultMessageText() {
4336                 global $wgContLang;
4337
4338                 if ( $this->getNamespace() != NS_MEDIAWIKI ) { // Just in case
4339                         return false;
4340                 }
4341
4342                 list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4343                 $message = wfMessage( $name )->inLanguage( $lang )->useDatabase( false );
4344
4345                 if ( $message->exists() ) {
4346                         return $message->plain();
4347                 } else {
4348                         return false;
4349                 }
4350         }
4351
4352         /**
4353          * Updates page_touched for this page; called from LinksUpdate.php
4354          *
4355          * @return Bool true if the update succeded
4356          */
4357         public function invalidateCache() {
4358                 if ( wfReadOnly() ) {
4359                         return false;
4360                 }
4361                 $dbw = wfGetDB( DB_MASTER );
4362                 $success = $dbw->update(
4363                         'page',
4364                         array( 'page_touched' => $dbw->timestamp() ),
4365                         $this->pageCond(),
4366                         __METHOD__
4367                 );
4368                 HTMLFileCache::clearFileCache( $this );
4369                 return $success;
4370         }
4371
4372         /**
4373          * Update page_touched timestamps and send squid purge messages for
4374          * pages linking to this title. May be sent to the job queue depending
4375          * on the number of links. Typically called on create and delete.
4376          */
4377         public function touchLinks() {
4378                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
4379                 $u->doUpdate();
4380
4381                 if ( $this->getNamespace() == NS_CATEGORY ) {
4382                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
4383                         $u->doUpdate();
4384                 }
4385         }
4386
4387         /**
4388          * Get the last touched timestamp
4389          *
4390          * @param $db DatabaseBase: optional db
4391          * @return String last-touched timestamp
4392          */
4393         public function getTouched( $db = null ) {
4394                 $db = isset( $db ) ? $db : wfGetDB( DB_SLAVE );
4395                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
4396                 return $touched;
4397         }
4398
4399         /**
4400          * Get the timestamp when this page was updated since the user last saw it.
4401          *
4402          * @param $user User
4403          * @return String|Null
4404          */
4405         public function getNotificationTimestamp( $user = null ) {
4406                 global $wgUser, $wgShowUpdatedMarker;
4407                 // Assume current user if none given
4408                 if ( !$user ) {
4409                         $user = $wgUser;
4410                 }
4411                 // Check cache first
4412                 $uid = $user->getId();
4413                 // avoid isset here, as it'll return false for null entries
4414                 if ( array_key_exists( $uid, $this->mNotificationTimestamp ) ) {
4415                         return $this->mNotificationTimestamp[$uid];
4416                 }
4417                 if ( !$uid || !$wgShowUpdatedMarker ) {
4418                         return $this->mNotificationTimestamp[$uid] = false;
4419                 }
4420                 // Don't cache too much!
4421                 if ( count( $this->mNotificationTimestamp ) >= self::CACHE_MAX ) {
4422                         $this->mNotificationTimestamp = array();
4423                 }
4424                 $dbr = wfGetDB( DB_SLAVE );
4425                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
4426                         'wl_notificationtimestamp',
4427                         array(
4428                                 'wl_user' => $user->getId(),
4429                                 'wl_namespace' => $this->getNamespace(),
4430                                 'wl_title' => $this->getDBkey(),
4431                         ),
4432                         __METHOD__
4433                 );
4434                 return $this->mNotificationTimestamp[$uid];
4435         }
4436
4437         /**
4438          * Generate strings used for xml 'id' names in monobook tabs
4439          *
4440          * @param $prepend string defaults to 'nstab-'
4441          * @return String XML 'id' name
4442          */
4443         public function getNamespaceKey( $prepend = 'nstab-' ) {
4444                 global $wgContLang;
4445                 // Gets the subject namespace if this title
4446                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
4447                 // Checks if cononical namespace name exists for namespace
4448                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
4449                         // Uses canonical namespace name
4450                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
4451                 } else {
4452                         // Uses text of namespace
4453                         $namespaceKey = $this->getSubjectNsText();
4454                 }
4455                 // Makes namespace key lowercase
4456                 $namespaceKey = $wgContLang->lc( $namespaceKey );
4457                 // Uses main
4458                 if ( $namespaceKey == '' ) {
4459                         $namespaceKey = 'main';
4460                 }
4461                 // Changes file to image for backwards compatibility
4462                 if ( $namespaceKey == 'file' ) {
4463                         $namespaceKey = 'image';
4464                 }
4465                 return $prepend . $namespaceKey;
4466         }
4467
4468         /**
4469          * Get all extant redirects to this Title
4470          *
4471          * @param $ns Int|Null Single namespace to consider; NULL to consider all namespaces
4472          * @return Array of Title redirects to this title
4473          */
4474         public function getRedirectsHere( $ns = null ) {
4475                 $redirs = array();
4476
4477                 $dbr = wfGetDB( DB_SLAVE );
4478                 $where = array(
4479                         'rd_namespace' => $this->getNamespace(),
4480                         'rd_title' => $this->getDBkey(),
4481                         'rd_from = page_id'
4482                 );
4483                 if ( $this->isExternal() ) {
4484                         $where['rd_interwiki'] = $this->getInterwiki();
4485                 } else {
4486                         $where[] = 'rd_interwiki = ' . $dbr->addQuotes( '' ) . ' OR rd_interwiki IS NULL';
4487                 }
4488                 if ( !is_null( $ns ) ) {
4489                         $where['page_namespace'] = $ns;
4490                 }
4491
4492                 $res = $dbr->select(
4493                         array( 'redirect', 'page' ),
4494                         array( 'page_namespace', 'page_title' ),
4495                         $where,
4496                         __METHOD__
4497                 );
4498
4499                 foreach ( $res as $row ) {
4500                         $redirs[] = self::newFromRow( $row );
4501                 }
4502                 return $redirs;
4503         }
4504
4505         /**
4506          * Check if this Title is a valid redirect target
4507          *
4508          * @return Bool
4509          */
4510         public function isValidRedirectTarget() {
4511                 global $wgInvalidRedirectTargets;
4512
4513                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
4514                 if ( $this->isSpecial( 'Userlogout' ) ) {
4515                         return false;
4516                 }
4517
4518                 foreach ( $wgInvalidRedirectTargets as $target ) {
4519                         if ( $this->isSpecial( $target ) ) {
4520                                 return false;
4521                         }
4522                 }
4523
4524                 return true;
4525         }
4526
4527         /**
4528          * Get a backlink cache object
4529          *
4530          * @return BacklinkCache
4531          */
4532         public function getBacklinkCache() {
4533                 return BacklinkCache::get( $this );
4534         }
4535
4536         /**
4537          * Whether the magic words __INDEX__ and __NOINDEX__ function for  this page.
4538          *
4539          * @return Boolean
4540          */
4541         public function canUseNoindex() {
4542                 global $wgContentNamespaces, $wgExemptFromUserRobotsControl;
4543
4544                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
4545                         ? $wgContentNamespaces
4546                         : $wgExemptFromUserRobotsControl;
4547
4548                 return !in_array( $this->mNamespace, $bannedNamespaces );
4549
4550         }
4551
4552         /**
4553          * Returns the raw sort key to be used for categories, with the specified
4554          * prefix.  This will be fed to Collation::getSortKey() to get a
4555          * binary sortkey that can be used for actual sorting.
4556          *
4557          * @param $prefix string The prefix to be used, specified using
4558          *   {{defaultsort:}} or like [[Category:Foo|prefix]].  Empty for no
4559          *   prefix.
4560          * @return string
4561          */
4562         public function getCategorySortkey( $prefix = '' ) {
4563                 $unprefixed = $this->getText();
4564
4565                 // Anything that uses this hook should only depend
4566                 // on the Title object passed in, and should probably
4567                 // tell the users to run updateCollations.php --force
4568                 // in order to re-sort existing category relations.
4569                 wfRunHooks( 'GetDefaultSortkey', array( $this, &$unprefixed ) );
4570                 if ( $prefix !== '' ) {
4571                         # Separate with a line feed, so the unprefixed part is only used as
4572                         # a tiebreaker when two pages have the exact same prefix.
4573                         # In UCA, tab is the only character that can sort above LF
4574                         # so we strip both of them from the original prefix.
4575                         $prefix = strtr( $prefix, "\n\t", '  ' );
4576                         return "$prefix\n$unprefixed";
4577                 }
4578                 return $unprefixed;
4579         }
4580
4581         /**
4582          * Get the language in which the content of this page is written in
4583          * wikitext. Defaults to $wgContLang, but in certain cases it can be
4584          * e.g. $wgLang (such as special pages, which are in the user language).
4585          *
4586          * @since 1.18
4587          * @return Language
4588          */
4589         public function getPageLanguage() {
4590                 global $wgLang;
4591                 if ( $this->isSpecialPage() ) {
4592                         // special pages are in the user language
4593                         return $wgLang;
4594                 }
4595
4596                 //TODO: use the LinkCache to cache this! Note that this may depend on user settings, so the cache should be only per-request.
4597                 //NOTE: ContentHandler::getPageLanguage() may need to load the content to determine the page language!
4598                 $contentHandler = ContentHandler::getForTitle( $this );
4599                 $pageLang = $contentHandler->getPageLanguage( $this );
4600
4601                 // Hook at the end because we don't want to override the above stuff
4602                 wfRunHooks( 'PageContentLanguage', array( $this, &$pageLang, $wgLang ) );
4603                 return wfGetLangObj( $pageLang );
4604         }
4605
4606         /**
4607          * Get the language in which the content of this page is written when
4608          * viewed by user. Defaults to $wgContLang, but in certain cases it can be
4609          * e.g. $wgLang (such as special pages, which are in the user language).
4610          *
4611          * @since 1.20
4612          * @return Language
4613          */
4614         public function getPageViewLanguage() {
4615                 global $wgLang;
4616
4617                 if ( $this->isSpecialPage() ) {
4618                         // If the user chooses a variant, the content is actually
4619                         // in a language whose code is the variant code.
4620                         $variant = $wgLang->getPreferredVariant();
4621                         if ( $wgLang->getCode() !== $variant ) {
4622                                 return Language::factory( $variant );
4623                         }
4624
4625                         return $wgLang;
4626                 }
4627
4628                 //NOTE: can't be cached persistently, depends on user settings
4629                 //NOTE: ContentHandler::getPageViewLanguage() may need to load the content to determine the page language!
4630                 $contentHandler = ContentHandler::getForTitle( $this );
4631                 $pageLang = $contentHandler->getPageViewLanguage( $this );
4632                 return $pageLang;
4633         }
4634 }