includes/Title.php

   1 <?php
   2 /**
   3  * See title.txt
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 /**
  24  * Represents a title within MediaWiki.
  25  * Optionally may contain an interwiki designation or namespace.
  26  * @note This class can fetch various kinds of data from the database;
  27  *       however, it does so inefficiently.
  28  *
  29  * @internal documentation reviewed 15 Mar 2010
  30  */
  31 class Title {
  32         /** @name Static cache variables */
  33         // @{
  34         static private $titleCache = array();
  35         // @}
  36
  37         /**
  38          * Title::newFromText maintains a cache to avoid expensive re-normalization of
  39          * commonly used titles. On a batch operation this can become a memory leak
  40          * if not bounded. After hitting this many titles reset the cache.
  41          */
  42         const CACHE_MAX = 1000;
  43
  44         /**
  45          * Used to be GAID_FOR_UPDATE define. Used with getArticleID() and friends
  46          * to use the master DB
  47          */
  48         const GAID_FOR_UPDATE = 1;
  49
  50         /**
  51          * @name Private member variables
  52          * Please use the accessor functions instead.
  53          * @private
  54          */
  55         // @{
  56
  57         var $mTextform = '';              // /< Text form (spaces not underscores) of the main part
  58         var $mUrlform = '';               // /< URL-encoded form of the main part
  59         var $mDbkeyform = '';             // /< Main part with underscores
  60         var $mUserCaseDBKey;              // /< DB key with the initial letter in the case specified by the user
  61         var $mNamespace = NS_MAIN;        // /< Namespace index, i.e. one of the NS_xxxx constants
  62         var $mInterwiki = '';             // /< Interwiki prefix (or null string)
  63         var $mFragment;                   // /< Title fragment (i.e. the bit after the #)
  64         var $mArticleID = -1;             // /< Article ID, fetched from the link cache on demand
  65         var $mLatestID = false;           // /< ID of most recent revision
  66         var $mCounter = -1;               // /< Number of times this page has been viewed (-1 means "not loaded")
  67         var $mRestrictions = array();     // /< Array of groups allowed to edit this article
  68         var $mOldRestrictions = false;
  69         var $mCascadeRestriction;         ///< Cascade restrictions on this page to included templates and images?
  70         var $mCascadingRestrictions;      // Caching the results of getCascadeProtectionSources
  71         var $mRestrictionsExpiry = array(); ///< When do the restrictions on this page expire?
  72         var $mHasCascadingRestrictions;   ///< Are cascading restrictions in effect on this page?
  73         var $mCascadeSources;             ///< Where are the cascading restrictions coming from on this page?
  74         var $mRestrictionsLoaded = false; ///< Boolean for initialisation on demand
  75         var $mPrefixedText;               ///< Text form including namespace/interwiki, initialised on demand
  76         var $mTitleProtection;            ///< Cached value for getTitleProtection (create protection)
  77         # Don't change the following default, NS_MAIN is hardcoded in several
  78         # places.  See bug 696.
  79         var $mDefaultNamespace = NS_MAIN; // /< Namespace index when there is no namespace
  80                                                                           # Zero except in {{transclusion}} tags
  81         var $mWatched = null;             // /< Is $wgUser watching this page? null if unfilled, accessed through userIsWatching()
  82         var $mLength = -1;                // /< The page length, 0 for special pages
  83         var $mRedirect = null;            // /< Is the article at this title a redirect?
  84         var $mNotificationTimestamp = array(); // /< Associative array of user ID -> timestamp/false
  85         var $mBacklinkCache = null;       // /< Cache of links to this title
  86         // @}
  87
  88
  89         /**
  90          * Constructor
  91          */
  92         /*protected*/ function __construct() { }
  93
  94         /**
  95          * Create a new Title from a prefixed DB key
  96          *
  97          * @param $key String the database key, which has underscores
  98          *      instead of spaces, possibly including namespace and
  99          *      interwiki prefixes
 100          * @return Title, or NULL on an error
 101          */
 102         public static function newFromDBkey( $key ) {
 103                 $t = new Title();
 104                 $t->mDbkeyform = $key;
 105                 if ( $t->secureAndSplit() ) {
 106                         return $t;
 107                 } else {
 108                         return null;
 109                 }
 110         }
 111
 112         /**
 113          * Create a new Title from text, such as what one would find in a link. De-
 114          * codes any HTML entities in the text.
 115          *
 116          * @param $text String the link text; spaces, prefixes, and an
 117          *   initial ':' indicating the main namespace are accepted.
 118          * @param $defaultNamespace Int the namespace to use if none is speci-
 119          *   fied by a prefix.  If you want to force a specific namespace even if
 120          *   $text might begin with a namespace prefix, use makeTitle() or
 121          *   makeTitleSafe().
 122          * @return Title, or null on an error.
 123          */
 124         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 125                 if ( is_object( $text ) ) {
 126                         throw new MWException( 'Title::newFromText given an object' );
 127                 }
 128
 129                 /**
 130                  * Wiki pages often contain multiple links to the same page.
 131                  * Title normalization and parsing can become expensive on
 132                  * pages with many links, so we can save a little time by
 133                  * caching them.
 134                  *
 135                  * In theory these are value objects and won't get changed...
 136                  */
 137                 if ( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 138                         return Title::$titleCache[$text];
 139                 }
 140
 141                 # Convert things like &eacute; &#257; or &#x3017; into normalized (bug 14952) text
 142                 $filteredText = Sanitizer::decodeCharReferencesAndNormalize( $text );
 143
 144                 $t = new Title();
 145                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 146                 $t->mDefaultNamespace = $defaultNamespace;
 147
 148                 static $cachedcount = 0 ;
 149                 if ( $t->secureAndSplit() ) {
 150                         if ( $defaultNamespace == NS_MAIN ) {
 151                                 if ( $cachedcount >= self::CACHE_MAX ) {
 152                                         # Avoid memory leaks on mass operations...
 153                                         Title::$titleCache = array();
 154                                         $cachedcount = 0;
 155                                 }
 156                                 $cachedcount++;
 157                                 Title::$titleCache[$text] =& $t;
 158                         }
 159                         return $t;
 160                 } else {
 161                         $ret = null;
 162                         return $ret;
 163                 }
 164         }
 165
 166         /**
 167          * THIS IS NOT THE FUNCTION YOU WANT. Use Title::newFromText().
 168          *
 169          * Example of wrong and broken code:
 170          * $title = Title::newFromURL( $wgRequest->getVal( 'title' ) );
 171          *
 172          * Example of right code:
 173          * $title = Title::newFromText( $wgRequest->getVal( 'title' ) );
 174          *
 175          * Create a new Title from URL-encoded text. Ensures that
 176          * the given title's length does not exceed the maximum.
 177          *
 178          * @param $url String the title, as might be taken from a URL
 179          * @return Title the new object, or NULL on an error
 180          */
 181         public static function newFromURL( $url ) {
 182                 global $wgLegalTitleChars;
 183                 $t = new Title();
 184
 185                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 186                 # but some URLs used it as a space replacement and they still come
 187                 # from some external search tools.
 188                 if ( strpos( $wgLegalTitleChars, '+' ) === false ) {
 189                         $url = str_replace( '+', ' ', $url );
 190                 }
 191
 192                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 193                 if ( $t->secureAndSplit() ) {
 194                         return $t;
 195                 } else {
 196                         return null;
 197                 }
 198         }
 199
 200         /**
 201          * Create a new Title from an article ID
 202          *
 203          * @param $id Int the page_id corresponding to the Title to create
 204          * @param $flags Int use Title::GAID_FOR_UPDATE to use master
 205          * @return Title the new object, or NULL on an error
 206          */
 207         public static function newFromID( $id, $flags = 0 ) {
 208                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
 209                 $row = $db->selectRow( 'page', '*', array( 'page_id' => $id ), __METHOD__ );
 210                 if ( $row !== false ) {
 211                         $title = Title::newFromRow( $row );
 212                 } else {
 213                         $title = null;
 214                 }
 215                 return $title;
 216         }
 217
 218         /**
 219          * Make an array of titles from an array of IDs
 220          *
 221          * @param $ids Array of Int Array of IDs
 222          * @return Array of Titles
 223          */
 224         public static function newFromIDs( $ids ) {
 225                 if ( !count( $ids ) ) {
 226                         return array();
 227                 }
 228                 $dbr = wfGetDB( DB_SLAVE );
 229
 230                 $res = $dbr->select(
 231                         'page',
 232                         array(
 233                                 'page_namespace', 'page_title', 'page_id',
 234                                 'page_len', 'page_is_redirect', 'page_latest',
 235                         ),
 236                         array( 'page_id' => $ids ),
 237                         __METHOD__
 238                 );
 239
 240                 $titles = array();
 241                 foreach ( $res as $row ) {
 242                         $titles[] = Title::newFromRow( $row );
 243                 }
 244                 return $titles;
 245         }
 246
 247         /**
 248          * Make a Title object from a DB row
 249          *
 250          * @param $row Object database row (needs at least page_title,page_namespace)
 251          * @return Title corresponding Title
 252          */
 253         public static function newFromRow( $row ) {
 254                 $t = self::makeTitle( $row->page_namespace, $row->page_title );
 255                 $t->loadFromRow( $row );
 256                 return $t;
 257         }
 258
 259         /**
 260          * Load Title object fields from a DB row.
 261          * If false is given, the title will be treated as non-existing.
 262          *
 263          * @param $row Object|false database row
 264          * @return void
 265          */
 266         public function loadFromRow( $row ) {
 267                 if ( $row ) { // page found
 268                         if ( isset( $row->page_id ) )
 269                                 $this->mArticleID = (int)$row->page_id;
 270                         if ( isset( $row->page_len ) )
 271                                 $this->mLength = (int)$row->page_len;
 272                         if ( isset( $row->page_is_redirect ) )
 273                                 $this->mRedirect = (bool)$row->page_is_redirect;
 274                         if ( isset( $row->page_latest ) )
 275                                 $this->mLatestID = (int)$row->page_latest;
 276                         if ( isset( $row->page_counter ) )
 277                                 $this->mCounter = (int)$row->page_counter;
 278                 } else { // page not found
 279                         $this->mArticleID = 0;
 280                         $this->mLength = 0;
 281                         $this->mRedirect = false;
 282                         $this->mLatestID = 0;
 283                         $this->mCounter = 0;
 284                 }
 285         }
 286
 287         /**
 288          * Create a new Title from a namespace index and a DB key.
 289          * It's assumed that $ns and $title are *valid*, for instance when
 290          * they came directly from the database or a special page name.
 291          * For convenience, spaces are converted to underscores so that
 292          * eg user_text fields can be used directly.
 293          *
 294          * @param $ns Int the namespace of the article
 295          * @param $title String the unprefixed database key form
 296          * @param $fragment String the link fragment (after the "#")
 297          * @param $interwiki String the interwiki prefix
 298          * @return Title the new object
 299          */
 300         public static function &makeTitle( $ns, $title, $fragment = '', $interwiki = '' ) {
 301                 $t = new Title();
 302                 $t->mInterwiki = $interwiki;
 303                 $t->mFragment = $fragment;
 304                 $t->mNamespace = $ns = intval( $ns );
 305                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 306                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 307                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 308                 $t->mTextform = str_replace( '_', ' ', $title );
 309                 return $t;
 310         }
 311
 312         /**
 313          * Create a new Title from a namespace index and a DB key.
 314          * The parameters will be checked for validity, which is a bit slower
 315          * than makeTitle() but safer for user-provided data.
 316          *
 317          * @param $ns Int the namespace of the article
 318          * @param $title String database key form
 319          * @param $fragment String the link fragment (after the "#")
 320          * @param $interwiki String interwiki prefix
 321          * @return Title the new object, or NULL on an error
 322          */
 323         public static function makeTitleSafe( $ns, $title, $fragment = '', $interwiki = '' ) {
 324                 $t = new Title();
 325                 $t->mDbkeyform = Title::makeName( $ns, $title, $fragment, $interwiki );
 326                 if ( $t->secureAndSplit() ) {
 327                         return $t;
 328                 } else {
 329                         return null;
 330                 }
 331         }
 332
 333         /**
 334          * Create a new Title for the Main Page
 335          *
 336          * @return Title the new object
 337          */
 338         public static function newMainPage() {
 339                 $title = Title::newFromText( wfMsgForContent( 'mainpage' ) );
 340                 // Don't give fatal errors if the message is broken
 341                 if ( !$title ) {
 342                         $title = Title::newFromText( 'Main Page' );
 343                 }
 344                 return $title;
 345         }
 346
 347         /**
 348          * Extract a redirect destination from a string and return the
 349          * Title, or null if the text doesn't contain a valid redirect
 350          * This will only return the very next target, useful for
 351          * the redirect table and other checks that don't need full recursion
 352          *
 353          * @param $text String: Text with possible redirect
 354          * @return Title: The corresponding Title
 355          */
 356         public static function newFromRedirect( $text ) {
 357                 return self::newFromRedirectInternal( $text );
 358         }
 359
 360         /**
 361          * Extract a redirect destination from a string and return the
 362          * Title, or null if the text doesn't contain a valid redirect
 363          * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
 364          * in order to provide (hopefully) the Title of the final destination instead of another redirect
 365          *
 366          * @param $text String Text with possible redirect
 367          * @return Title
 368          */
 369         public static function newFromRedirectRecurse( $text ) {
 370                 $titles = self::newFromRedirectArray( $text );
 371                 return $titles ? array_pop( $titles ) : null;
 372         }
 373
 374         /**
 375          * Extract a redirect destination from a string and return an
 376          * array of Titles, or null if the text doesn't contain a valid redirect
 377          * The last element in the array is the final destination after all redirects
 378          * have been resolved (up to $wgMaxRedirects times)
 379          *
 380          * @param $text String Text with possible redirect
 381          * @return Array of Titles, with the destination last
 382          */
 383         public static function newFromRedirectArray( $text ) {
 384                 global $wgMaxRedirects;
 385                 $title = self::newFromRedirectInternal( $text );
 386                 if ( is_null( $title ) ) {
 387                         return null;
 388                 }
 389                 // recursive check to follow double redirects
 390                 $recurse = $wgMaxRedirects;
 391                 $titles = array( $title );
 392                 while ( --$recurse > 0 ) {
 393                         if ( $title->isRedirect() ) {
 394                                 $page = WikiPage::factory( $title );
 395                                 $newtitle = $page->getRedirectTarget();
 396                         } else {
 397                                 break;
 398                         }
 399                         // Redirects to some special pages are not permitted
 400                         if ( $newtitle instanceOf Title && $newtitle->isValidRedirectTarget() ) {
 401                                 // the new title passes the checks, so make that our current title so that further recursion can be checked
 402                                 $title = $newtitle;
 403                                 $titles[] = $newtitle;
 404                         } else {
 405                                 break;
 406                         }
 407                 }
 408                 return $titles;
 409         }
 410
 411         /**
 412          * Really extract the redirect destination
 413          * Do not call this function directly, use one of the newFromRedirect* functions above
 414          *
 415          * @param $text String Text with possible redirect
 416          * @return Title
 417          */
 418         protected static function newFromRedirectInternal( $text ) {
 419                 global $wgMaxRedirects;
 420                 if ( $wgMaxRedirects < 1 ) {
 421                         //redirects are disabled, so quit early
 422                         return null;
 423                 }
 424                 $redir = MagicWord::get( 'redirect' );
 425                 $text = trim( $text );
 426                 if ( $redir->matchStartAndRemove( $text ) ) {
 427                         // Extract the first link and see if it's usable
 428                         // Ensure that it really does come directly after #REDIRECT
 429                         // Some older redirects included a colon, so don't freak about that!
 430                         $m = array();
 431                         if ( preg_match( '!^\s*:?\s*\[{2}(.*?)(?:\|.*?)?\]{2}!', $text, $m ) ) {
 432                                 // Strip preceding colon used to "escape" categories, etc.
 433                                 // and URL-decode links
 434                                 if ( strpos( $m[1], '%' ) !== false ) {
 435                                         // Match behavior of inline link parsing here;
 436                                         $m[1] = rawurldecode( ltrim( $m[1], ':' ) );
 437                                 }
 438                                 $title = Title::newFromText( $m[1] );
 439                                 // If the title is a redirect to bad special pages or is invalid, return null
 440                                 if ( !$title instanceof Title || !$title->isValidRedirectTarget() ) {
 441                                         return null;
 442                                 }
 443                                 return $title;
 444                         }
 445                 }
 446                 return null;
 447         }
 448
 449         /**
 450          * Get the prefixed DB key associated with an ID
 451          *
 452          * @param $id Int the page_id of the article
 453          * @return Title an object representing the article, or NULL if no such article was found
 454          */
 455         public static function nameOf( $id ) {
 456                 $dbr = wfGetDB( DB_SLAVE );
 457
 458                 $s = $dbr->selectRow(
 459                         'page',
 460                         array( 'page_namespace', 'page_title' ),
 461                         array( 'page_id' => $id ),
 462                         __METHOD__
 463                 );
 464                 if ( $s === false ) {
 465                         return null;
 466                 }
 467
 468                 $n = self::makeName( $s->page_namespace, $s->page_title );
 469                 return $n;
 470         }
 471
 472         /**
 473          * Get a regex character class describing the legal characters in a link
 474          *
 475          * @return String the list of characters, not delimited
 476          */
 477         public static function legalChars() {
 478                 global $wgLegalTitleChars;
 479                 return $wgLegalTitleChars;
 480         }
 481
 482         /**
 483          * Returns a simple regex that will match on characters and sequences invalid in titles.
 484          * Note that this doesn't pick up many things that could be wrong with titles, but that
 485          * replacing this regex with something valid will make many titles valid.
 486          *
 487          * @return String regex string
 488          */
 489         static function getTitleInvalidRegex() {
 490                 static $rxTc = false;
 491                 if ( !$rxTc ) {
 492                         # Matching titles will be held as illegal.
 493                         $rxTc = '/' .
 494                                 # Any character not allowed is forbidden...
 495                                 '[^' . self::legalChars() . ']' .
 496                                 # URL percent encoding sequences interfere with the ability
 497                                 # to round-trip titles -- you can't link to them consistently.
 498                                 '|%[0-9A-Fa-f]{2}' .
 499                                 # XML/HTML character references produce similar issues.
 500                                 '|&[A-Za-z0-9\x80-\xff]+;' .
 501                                 '|&#[0-9]+;' .
 502                                 '|&#x[0-9A-Fa-f]+;' .
 503                                 '/S';
 504                 }
 505
 506                 return $rxTc;
 507         }
 508
 509         /**
 510          * Get a string representation of a title suitable for
 511          * including in a search index
 512          *
 513          * @param $ns Int a namespace index
 514          * @param $title String text-form main part
 515          * @return String a stripped-down title string ready for the search index
 516          */
 517         public static function indexTitle( $ns, $title ) {
 518                 global $wgContLang;
 519
 520                 $lc = SearchEngine::legalSearchChars() . '&#;';
 521                 $t = $wgContLang->normalizeForSearch( $title );
 522                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 523                 $t = $wgContLang->lc( $t );
 524
 525                 # Handle 's, s'
 526                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 527                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 528
 529                 $t = preg_replace( "/\\s+/", ' ', $t );
 530
 531                 if ( $ns == NS_FILE ) {
 532                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 533                 }
 534                 return trim( $t );
 535         }
 536
 537         /**
 538          * Make a prefixed DB key from a DB key and a namespace index
 539          *
 540          * @param $ns Int numerical representation of the namespace
 541          * @param $title String the DB key form the title
 542          * @param $fragment String The link fragment (after the "#")
 543          * @param $interwiki String The interwiki prefix
 544          * @return String the prefixed form of the title
 545          */
 546         public static function makeName( $ns, $title, $fragment = '', $interwiki = '' ) {
 547                 global $wgContLang;
 548
 549                 $namespace = $wgContLang->getNsText( $ns );
 550                 $name = $namespace == '' ? $title : "$namespace:$title";
 551                 if ( strval( $interwiki ) != '' ) {
 552                         $name = "$interwiki:$name";
 553                 }
 554                 if ( strval( $fragment ) != '' ) {
 555                         $name .= '#' . $fragment;
 556                 }
 557                 return $name;
 558         }
 559
 560         /**
 561          * Escape a text fragment, say from a link, for a URL
 562          *
 563          * @param $fragment string containing a URL or link fragment (after the "#")
 564          * @return String: escaped string
 565          */
 566         static function escapeFragmentForURL( $fragment ) {
 567                 # Note that we don't urlencode the fragment.  urlencoded Unicode
 568                 # fragments appear not to work in IE (at least up to 7) or in at least
 569                 # one version of Opera 9.x.  The W3C validator, for one, doesn't seem
 570                 # to care if they aren't encoded.
 571                 return Sanitizer::escapeId( $fragment, 'noninitial' );
 572         }
 573
 574         /**
 575          * Callback for usort() to do title sorts by (namespace, title)
 576          *
 577          * @param $a Title
 578          * @param $b Title
 579          *
 580          * @return Integer: result of string comparison, or namespace comparison
 581          */
 582         public static function compare( $a, $b ) {
 583                 if ( $a->getNamespace() == $b->getNamespace() ) {
 584                         return strcmp( $a->getText(), $b->getText() );
 585                 } else {
 586                         return $a->getNamespace() - $b->getNamespace();
 587                 }
 588         }
 589
 590         /**
 591          * Determine whether the object refers to a page within
 592          * this project.
 593          *
 594          * @return Bool TRUE if this is an in-project interwiki link or a wikilink, FALSE otherwise
 595          */
 596         public function isLocal() {
 597                 if ( $this->mInterwiki != '' ) {
 598                         return Interwiki::fetch( $this->mInterwiki )->isLocal();
 599                 } else {
 600                         return true;
 601                 }
 602         }
 603
 604         /**
 605          * Is this Title interwiki?
 606          *
 607          * @return Bool
 608          */
 609         public function isExternal() {
 610                 return ( $this->mInterwiki != '' );
 611         }
 612
 613         /**
 614          * Get the interwiki prefix (or null string)
 615          *
 616          * @return String Interwiki prefix
 617          */
 618         public function getInterwiki() {
 619                 return $this->mInterwiki;
 620         }
 621
 622         /**
 623          * Determine whether the object refers to a page within
 624          * this project and is transcludable.
 625          *
 626          * @return Bool TRUE if this is transcludable
 627          */
 628         public function isTrans() {
 629                 if ( $this->mInterwiki == '' ) {
 630                         return false;
 631                 }
 632
 633                 return Interwiki::fetch( $this->mInterwiki )->isTranscludable();
 634         }
 635
 636         /**
 637          * Returns the DB name of the distant wiki which owns the object.
 638          *
 639          * @return String the DB name
 640          */
 641         public function getTransWikiID() {
 642                 if ( $this->mInterwiki == '' ) {
 643                         return false;
 644                 }
 645
 646                 return Interwiki::fetch( $this->mInterwiki )->getWikiID();
 647         }
 648
 649         /**
 650          * Get the text form (spaces not underscores) of the main part
 651          *
 652          * @return String Main part of the title
 653          */
 654         public function getText() {
 655                 return $this->mTextform;
 656         }
 657
 658         /**
 659          * Get the URL-encoded form of the main part
 660          *
 661          * @return String Main part of the title, URL-encoded
 662          */
 663         public function getPartialURL() {
 664                 return $this->mUrlform;
 665         }
 666
 667         /**
 668          * Get the main part with underscores
 669          *
 670          * @return String: Main part of the title, with underscores
 671          */
 672         public function getDBkey() {
 673                 return $this->mDbkeyform;
 674         }
 675
 676         /**
 677          * Get the DB key with the initial letter case as specified by the user
 678          *
 679          * @return String DB key
 680          */
 681         function getUserCaseDBKey() {
 682                 return $this->mUserCaseDBKey;
 683         }
 684
 685         /**
 686          * Get the namespace index, i.e. one of the NS_xxxx constants.
 687          *
 688          * @return Integer: Namespace index
 689          */
 690         public function getNamespace() {
 691                 return $this->mNamespace;
 692         }
 693
 694         /**
 695          * Get the namespace text
 696          *
 697          * @return String: Namespace text
 698          */
 699         public function getNsText() {
 700                 global $wgContLang;
 701
 702                 if ( $this->mInterwiki != '' ) {
 703                         // This probably shouldn't even happen. ohh man, oh yuck.
 704                         // But for interwiki transclusion it sometimes does.
 705                         // Shit. Shit shit shit.
 706                         //
 707                         // Use the canonical namespaces if possible to try to
 708                         // resolve a foreign namespace.
 709                         if ( MWNamespace::exists( $this->mNamespace ) ) {
 710                                 return MWNamespace::getCanonicalName( $this->mNamespace );
 711                         }
 712                 }
 713
 714                 // Strip off subpages
 715                 $pagename = $this->getText();
 716                 if ( strpos( $pagename, '/' ) !== false ) {
 717                         list( $username , ) = explode( '/', $pagename, 2 );
 718                 } else {
 719                         $username = $pagename;
 720                 }
 721
 722                 if ( $wgContLang->needsGenderDistinction() &&
 723                                 MWNamespace::hasGenderDistinction( $this->mNamespace ) ) {
 724                         $gender = GenderCache::singleton()->getGenderOf( $username, __METHOD__ );
 725                         return $wgContLang->getGenderNsText( $this->mNamespace, $gender );
 726                 }
 727
 728                 return $wgContLang->getNsText( $this->mNamespace );
 729         }
 730
 731         /**
 732          * Get the namespace text of the subject (rather than talk) page
 733          *
 734          * @return String Namespace text
 735          */
 736         public function getSubjectNsText() {
 737                 global $wgContLang;
 738                 return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
 739         }
 740
 741         /**
 742          * Get the namespace text of the talk page
 743          *
 744          * @return String Namespace text
 745          */
 746         public function getTalkNsText() {
 747                 global $wgContLang;
 748                 return( $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) ) );
 749         }
 750
 751         /**
 752          * Could this title have a corresponding talk page?
 753          *
 754          * @return Bool TRUE or FALSE
 755          */
 756         public function canTalk() {
 757                 return( MWNamespace::canTalk( $this->mNamespace ) );
 758         }
 759
 760         /**
 761          * Is this in a namespace that allows actual pages?
 762          *
 763          * @return Bool
 764          * @internal note -- uses hardcoded namespace index instead of constants
 765          */
 766         public function canExist() {
 767                 return $this->mNamespace >= 0 && $this->mNamespace != NS_MEDIA;
 768         }
 769
 770         /**
 771          * Can this title be added to a user's watchlist?
 772          *
 773          * @return Bool TRUE or FALSE
 774          */
 775         public function isWatchable() {
 776                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
 777         }
 778
 779         /**
 780          * Returns true if this is a special page.
 781          *
 782          * @return boolean
 783          */
 784         public function isSpecialPage() {
 785                 return $this->getNamespace() == NS_SPECIAL;
 786         }
 787
 788         /**
 789          * Returns true if this title resolves to the named special page
 790          *
 791          * @param $name String The special page name
 792          * @return boolean
 793          */
 794         public function isSpecial( $name ) {
 795                 if ( $this->isSpecialPage() ) {
 796                         list( $thisName, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $this->getDBkey() );
 797                         if ( $name == $thisName ) {
 798                                 return true;
 799                         }
 800                 }
 801                 return false;
 802         }
 803
 804         /**
 805          * If the Title refers to a special page alias which is not the local default, resolve
 806          * the alias, and localise the name as necessary.  Otherwise, return $this
 807          *
 808          * @return Title
 809          */
 810         public function fixSpecialName() {
 811                 if ( $this->isSpecialPage() ) {
 812                         list( $canonicalName, $par ) = SpecialPageFactory::resolveAlias( $this->mDbkeyform );
 813                         if ( $canonicalName ) {
 814                                 $localName = SpecialPageFactory::getLocalNameFor( $canonicalName, $par );
 815                                 if ( $localName != $this->mDbkeyform ) {
 816                                         return Title::makeTitle( NS_SPECIAL, $localName );
 817                                 }
 818                         }
 819                 }
 820                 return $this;
 821         }
 822
 823         /**
 824          * Returns true if the title is inside the specified namespace.
 825          *
 826          * Please make use of this instead of comparing to getNamespace()
 827          * This function is much more resistant to changes we may make
 828          * to namespaces than code that makes direct comparisons.
 829          * @param $ns int The namespace
 830          * @return bool
 831          * @since 1.19
 832          */
 833         public function inNamespace( $ns ) {
 834                 return MWNamespace::equals( $this->getNamespace(), $ns );
 835         }
 836
 837         /**
 838          * Returns true if the title is inside one of the specified namespaces.
 839          *
 840          * @param ...$namespaces The namespaces to check for
 841          * @return bool
 842          * @since 1.19
 843          */
 844         public function inNamespaces( /* ... */ ) {
 845                 $namespaces = func_get_args();
 846                 if ( count( $namespaces ) > 0 && is_array( $namespaces[0] ) ) {
 847                         $namespaces = $namespaces[0];
 848                 }
 849
 850                 foreach ( $namespaces as $ns ) {
 851                         if ( $this->inNamespace( $ns ) ) {
 852                                 return true;
 853                         }
 854                 }
 855
 856                 return false;
 857         }
 858
 859         /**
 860          * Returns true if the title has the same subject namespace as the
 861          * namespace specified.
 862          * For example this method will take NS_USER and return true if namespace
 863          * is either NS_USER or NS_USER_TALK since both of them have NS_USER
 864          * as their subject namespace.
 865          *
 866          * This is MUCH simpler than individually testing for equivilance
 867          * against both NS_USER and NS_USER_TALK, and is also forward compatible.
 868          * @since 1.19
 869          */
 870         public function hasSubjectNamespace( $ns ) {
 871                 return MWNamespace::subjectEquals( $this->getNamespace(), $ns );
 872         }
 873
 874         /**
 875          * Is this Title in a namespace which contains content?
 876          * In other words, is this a content page, for the purposes of calculating
 877          * statistics, etc?
 878          *
 879          * @return Boolean
 880          */
 881         public function isContentPage() {
 882                 return MWNamespace::isContent( $this->getNamespace() );
 883         }
 884
 885         /**
 886          * Would anybody with sufficient privileges be able to move this page?
 887          * Some pages just aren't movable.
 888          *
 889          * @return Bool TRUE or FALSE
 890          */
 891         public function isMovable() {
 892                 if ( !MWNamespace::isMovable( $this->getNamespace() ) || $this->getInterwiki() != '' ) {
 893                         // Interwiki title or immovable namespace. Hooks don't get to override here
 894                         return false;
 895                 }
 896
 897                 $result = true;
 898                 wfRunHooks( 'TitleIsMovable', array( $this, &$result ) );
 899                 return $result;
 900         }
 901
 902         /**
 903          * Is this the mainpage?
 904          * @note Title::newFromText seams to be sufficiently optimized by the title
 905          * cache that we don't need to over-optimize by doing direct comparisons and
 906          * acidentally creating new bugs where $title->equals( Title::newFromText() )
 907          * ends up reporting something differently than $title->isMainPage();
 908          *
 909          * @since 1.18
 910          * @return Bool
 911          */
 912         public function isMainPage() {
 913                 return $this->equals( Title::newMainPage() );
 914         }
 915
 916         /**
 917          * Is this a subpage?
 918          *
 919          * @return Bool
 920          */
 921         public function isSubpage() {
 922                 return MWNamespace::hasSubpages( $this->mNamespace )
 923                         ? strpos( $this->getText(), '/' ) !== false
 924                         : false;
 925         }
 926
 927         /**
 928          * Is this a conversion table for the LanguageConverter?
 929          *
 930          * @return Bool
 931          */
 932         public function isConversionTable() {
 933                 return $this->getNamespace() == NS_MEDIAWIKI &&
 934                         strpos( $this->getText(), 'Conversiontable' ) !== false;
 935         }
 936
 937         /**
 938          * Does that page contain wikitext, or it is JS, CSS or whatever?
 939          *
 940          * @return Bool
 941          */
 942         public function isWikitextPage() {
 943                 $retval = !$this->isCssOrJsPage() && !$this->isCssJsSubpage();
 944                 wfRunHooks( 'TitleIsWikitextPage', array( $this, &$retval ) );
 945                 return $retval;
 946         }
 947
 948         /**
 949          * Could this page contain custom CSS or JavaScript, based
 950          * on the title?
 951          *
 952          * @return Bool
 953          */
 954         public function isCssOrJsPage() {
 955                 $retval = $this->mNamespace == NS_MEDIAWIKI
 956                         && preg_match( '!\.(?:css|js)$!u', $this->mTextform ) > 0;
 957                 wfRunHooks( 'TitleIsCssOrJsPage', array( $this, &$retval ) );
 958                 return $retval;
 959         }
 960
 961         /**
 962          * Is this a .css or .js subpage of a user page?
 963          * @return Bool
 964          */
 965         public function isCssJsSubpage() {
 966                 return ( NS_USER == $this->mNamespace and preg_match( "/\\/.*\\.(?:css|js)$/", $this->mTextform ) );
 967         }
 968
 969         /**
 970          * Is this a *valid* .css or .js subpage of a user page?
 971          *
 972          * @return Bool
 973          * @deprecated since 1.17
 974          */
 975         public function isValidCssJsSubpage() {
 976                 return $this->isCssJsSubpage();
 977         }
 978
 979         /**
 980          * Trim down a .css or .js subpage title to get the corresponding skin name
 981          *
 982          * @return string containing skin name from .css or .js subpage title
 983          */
 984         public function getSkinFromCssJsSubpage() {
 985                 $subpage = explode( '/', $this->mTextform );
 986                 $subpage = $subpage[ count( $subpage ) - 1 ];
 987                 $lastdot = strrpos( $subpage, '.' );
 988                 if ( $lastdot === false )
 989                         return $subpage; # Never happens: only called for names ending in '.css' or '.js'
 990                 return substr( $subpage, 0, $lastdot );
 991         }
 992
 993         /**
 994          * Is this a .css subpage of a user page?
 995          *
 996          * @return Bool
 997          */
 998         public function isCssSubpage() {
 999                 return ( NS_USER == $this->mNamespace && preg_match( "/\\/.*\\.css$/", $this->mTextform ) );
1000         }
1001
1002         /**
1003          * Is this a .js subpage of a user page?
1004          *
1005          * @return Bool
1006          */
1007         public function isJsSubpage() {
1008                 return ( NS_USER == $this->mNamespace && preg_match( "/\\/.*\\.js$/", $this->mTextform ) );
1009         }
1010
1011         /**
1012          * Is this a talk page of some sort?
1013          *
1014          * @return Bool
1015          */
1016         public function isTalkPage() {
1017                 return MWNamespace::isTalk( $this->getNamespace() );
1018         }
1019
1020         /**
1021          * Get a Title object associated with the talk page of this article
1022          *
1023          * @return Title the object for the talk page
1024          */
1025         public function getTalkPage() {
1026                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1027         }
1028
1029         /**
1030          * Get a title object associated with the subject page of this
1031          * talk page
1032          *
1033          * @return Title the object for the subject page
1034          */
1035         public function getSubjectPage() {
1036                 // Is this the same title?
1037                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
1038                 if ( $this->getNamespace() == $subjectNS ) {
1039                         return $this;
1040                 }
1041                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
1042         }
1043
1044         /**
1045          * Get the default namespace index, for when there is no namespace
1046          *
1047          * @return Int Default namespace index
1048          */
1049         public function getDefaultNamespace() {
1050                 return $this->mDefaultNamespace;
1051         }
1052
1053         /**
1054          * Get title for search index
1055          *
1056          * @return String a stripped-down title string ready for the
1057          *  search index
1058          */
1059         public function getIndexTitle() {
1060                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
1061         }
1062
1063         /**
1064          * Get the Title fragment (i.e.\ the bit after the #) in text form
1065          *
1066          * @return String Title fragment
1067          */
1068         public function getFragment() {
1069                 return $this->mFragment;
1070         }
1071
1072         /**
1073          * Get the fragment in URL form, including the "#" character if there is one
1074          * @return String Fragment in URL form
1075          */
1076         public function getFragmentForURL() {
1077                 if ( $this->mFragment == '' ) {
1078                         return '';
1079                 } else {
1080                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
1081                 }
1082         }
1083
1084         /**
1085          * Set the fragment for this title. Removes the first character from the
1086          * specified fragment before setting, so it assumes you're passing it with
1087          * an initial "#".
1088          *
1089          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
1090          * Still in active use privately.
1091          *
1092          * @param $fragment String text
1093          */
1094         public function setFragment( $fragment ) {
1095                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
1096         }
1097
1098         /**
1099          * Prefix some arbitrary text with the namespace or interwiki prefix
1100          * of this object
1101          *
1102          * @param $name String the text
1103          * @return String the prefixed text
1104          * @private
1105          */
1106         private function prefix( $name ) {
1107                 $p = '';
1108                 if ( $this->mInterwiki != '' ) {
1109                         $p = $this->mInterwiki . ':';
1110                 }
1111
1112                 if ( 0 != $this->mNamespace ) {
1113                         $p .= $this->getNsText() . ':';
1114                 }
1115                 return $p . $name;
1116         }
1117
1118         /**
1119          * Get the prefixed database key form
1120          *
1121          * @return String the prefixed title, with underscores and
1122          *  any interwiki and namespace prefixes
1123          */
1124         public function getPrefixedDBkey() {
1125                 $s = $this->prefix( $this->mDbkeyform );
1126                 $s = str_replace( ' ', '_', $s );
1127                 return $s;
1128         }
1129
1130         /**
1131          * Get the prefixed title with spaces.
1132          * This is the form usually used for display
1133          *
1134          * @return String the prefixed title, with spaces
1135          */
1136         public function getPrefixedText() {
1137                 // @todo FIXME: Bad usage of empty() ?
1138                 if ( empty( $this->mPrefixedText ) ) {
1139                         $s = $this->prefix( $this->mTextform );
1140                         $s = str_replace( '_', ' ', $s );
1141                         $this->mPrefixedText = $s;
1142                 }
1143                 return $this->mPrefixedText;
1144         }
1145
1146         /**
1147          * Return a string representation of this title
1148          *
1149          * @return String representation of this title
1150          */
1151         public function __toString() {
1152                 return $this->getPrefixedText();
1153         }
1154
1155         /**
1156          * Get the prefixed title with spaces, plus any fragment
1157          * (part beginning with '#')
1158          *
1159          * @return String the prefixed title, with spaces and the fragment, including '#'
1160          */
1161         public function getFullText() {
1162                 $text = $this->getPrefixedText();
1163                 if ( $this->mFragment != '' ) {
1164                         $text .= '#' . $this->mFragment;
1165                 }
1166                 return $text;
1167         }
1168
1169         /**
1170          * Get the base page name, i.e. the leftmost part before any slashes
1171          *
1172          * @return String Base name
1173          */
1174         public function getBaseText() {
1175                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1176                         return $this->getText();
1177                 }
1178
1179                 $parts = explode( '/', $this->getText() );
1180                 # Don't discard the real title if there's no subpage involved
1181                 if ( count( $parts ) > 1 ) {
1182                         unset( $parts[count( $parts ) - 1] );
1183                 }
1184                 return implode( '/', $parts );
1185         }
1186
1187         /**
1188          * Get the lowest-level subpage name, i.e. the rightmost part after any slashes
1189          *
1190          * @return String Subpage name
1191          */
1192         public function getSubpageText() {
1193                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1194                         return( $this->mTextform );
1195                 }
1196                 $parts = explode( '/', $this->mTextform );
1197                 return( $parts[count( $parts ) - 1] );
1198         }
1199
1200         /**
1201          * Get the HTML-escaped displayable text form.
1202          * Used for the title field in <a> tags.
1203          *
1204          * @return String the text, including any prefixes
1205          */
1206         public function getEscapedText() {
1207                 wfDeprecated( __METHOD__, '1.19' );
1208                 return htmlspecialchars( $this->getPrefixedText() );
1209         }
1210
1211         /**
1212          * Get a URL-encoded form of the subpage text
1213          *
1214          * @return String URL-encoded subpage name
1215          */
1216         public function getSubpageUrlForm() {
1217                 $text = $this->getSubpageText();
1218                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
1219                 return( $text );
1220         }
1221
1222         /**
1223          * Get a URL-encoded title (not an actual URL) including interwiki
1224          *
1225          * @return String the URL-encoded form
1226          */
1227         public function getPrefixedURL() {
1228                 $s = $this->prefix( $this->mDbkeyform );
1229                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
1230                 return $s;
1231         }
1232
1233         /**
1234          * Helper to fix up the get{Local,Full,Link,Canonical}URL args
1235          */
1236         private static function fixUrlQueryArgs( $query, $query2 ) {
1237                 if ( is_array( $query ) ) {
1238                         $query = wfArrayToCGI( $query );
1239                 }
1240                 if ( $query2 ) {
1241                         if ( is_string( $query2 ) ) {
1242                                 // $query2 is a string, we will consider this to be
1243                                 // a deprecated $variant argument and add it to the query
1244                                 $query2 = wfArrayToCGI( array( 'variant' => $query2 ) );
1245                         } else {
1246                                 $query2 = wfArrayToCGI( $query2 );
1247                         }
1248                         // If we have $query content add a & to it first
1249                         if ( $query ) {
1250                                 $query .= '&';
1251                         }
1252                         // Now append the queries together
1253                         $query .= $query2;
1254                 }
1255                 return $query;
1256         }
1257
1258         /**
1259          * Get a real URL referring to this title, with interwiki link and
1260          * fragment
1261          *
1262          * @param $query \twotypes{\string,\array} an optional query string, not used for interwiki
1263          *   links. Can be specified as an associative array as well, e.g.,
1264          *   array( 'action' => 'edit' ) (keys and values will be URL-escaped).
1265          * @param $variant String language variant of url (for sr, zh..)
1266          * @return String the URL
1267          */
1268         public function getFullURL( $query = '', $query2 = false ) {
1269                 $query = self::fixUrlQueryArgs( $query, $query2 );
1270
1271                 # Hand off all the decisions on urls to getLocalURL
1272                 $url = $this->getLocalURL( $query );
1273
1274                 # Expand the url to make it a full url. Note that getLocalURL has the
1275                 # potential to output full urls for a variety of reasons, so we use
1276                 # wfExpandUrl instead of simply prepending $wgServer
1277                 $url = wfExpandUrl( $url, PROTO_RELATIVE );
1278
1279                 # Finally, add the fragment.
1280                 $url .= $this->getFragmentForURL();
1281
1282                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
1283                 return $url;
1284         }
1285
1286         /**
1287          * Get a URL with no fragment or server name.  If this page is generated
1288          * with action=render, $wgServer is prepended.
1289          *
1290          * @param $query Mixed: an optional query string; if not specified,
1291          *   $wgArticlePath will be used.  Can be specified as an associative array
1292          *   as well, e.g., array( 'action' => 'edit' ) (keys and values will be
1293          *   URL-escaped).
1294          * @param $variant String language variant of url (for sr, zh..)
1295          * @return String the URL
1296          */
1297         public function getLocalURL( $query = '', $query2 = false ) {
1298                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
1299
1300                 $query = self::fixUrlQueryArgs( $query, $query2 );
1301
1302                 $interwiki = Interwiki::fetch( $this->mInterwiki );
1303                 if ( $interwiki ) {
1304                         $namespace = $this->getNsText();
1305                         if ( $namespace != '' ) {
1306                                 # Can this actually happen? Interwikis shouldn't be parsed.
1307                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
1308                                 $namespace .= ':';
1309                         }
1310                         $url = $interwiki->getURL( $namespace . $this->getDBkey() );
1311                         $url = wfAppendQuery( $url, $query );
1312                 } else {
1313                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
1314                         if ( $query == '' ) {
1315                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
1316                                 wfRunHooks( 'GetLocalURL::Article', array( &$this, &$url ) );
1317                         } else {
1318                                 global $wgVariantArticlePath, $wgActionPaths;
1319                                 $url = false;
1320                                 $matches = array();
1321
1322                                 if ( !empty( $wgActionPaths ) &&
1323                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
1324                                 {
1325                                         $action = urldecode( $matches[2] );
1326                                         if ( isset( $wgActionPaths[$action] ) ) {
1327                                                 $query = $matches[1];
1328                                                 if ( isset( $matches[4] ) ) {
1329                                                         $query .= $matches[4];
1330                                                 }
1331                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
1332                                                 if ( $query != '' ) {
1333                                                         $url = wfAppendQuery( $url, $query );
1334                                                 }
1335                                         }
1336                                 }
1337
1338                                 if ( $url === false &&
1339                                         $wgVariantArticlePath &&
1340                                         $this->getPageLanguage()->hasVariants() &&
1341                                         preg_match( '/^variant=([^&]*)$/', $query, $matches ) )
1342                                 {
1343                                         $variant = urldecode( $matches[1] );
1344                                         if ( $this->getPageLanguage()->hasVariant( $variant ) ) {
1345                                                 // Only do the variant replacement if the given variant is a valid
1346                                                 // variant for the page's language.
1347                                                 $url = str_replace( '$2', urlencode( $variant ), $wgVariantArticlePath );
1348                                                 $url = str_replace( '$1', $dbkey, $url );
1349                                         }
1350                                 }
1351
1352                                 if ( $url === false ) {
1353                                         if ( $query == '-' ) {
1354                                                 $query = '';
1355                                         }
1356                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
1357                                 }
1358                         }
1359
1360                         wfRunHooks( 'GetLocalURL::Internal', array( &$this, &$url, $query ) );
1361
1362                         // @todo FIXME: This causes breakage in various places when we
1363                         // actually expected a local URL and end up with dupe prefixes.
1364                         if ( $wgRequest->getVal( 'action' ) == 'render' ) {
1365                                 $url = $wgServer . $url;
1366                         }
1367                 }
1368                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
1369                 return $url;
1370         }
1371
1372         /**
1373          * Get a URL that's the simplest URL that will be valid to link, locally,
1374          * to the current Title.  It includes the fragment, but does not include
1375          * the server unless action=render is used (or the link is external).  If
1376          * there's a fragment but the prefixed text is empty, we just return a link
1377          * to the fragment.
1378          *
1379          * The result obviously should not be URL-escaped, but does need to be
1380          * HTML-escaped if it's being output in HTML.
1381          *
1382          * @param $query Array of Strings An associative array of key => value pairs for the
1383          *   query string.  Keys and values will be escaped.
1384          * @param $variant String language variant of URL (for sr, zh..).  Ignored
1385          *   for external links.  Default is "false" (same variant as current page,
1386          *   for anonymous users).
1387          * @return String the URL
1388          */
1389         public function getLinkURL( $query = '', $query2 = false ) {
1390                 wfProfileIn( __METHOD__ );
1391                 if ( $this->isExternal() ) {
1392                         $ret = $this->getFullURL( $query, $query2 );
1393                 } elseif ( $this->getPrefixedText() === '' && $this->getFragment() !== '' ) {
1394                         $ret = $this->getFragmentForURL();
1395                 } else {
1396                         $ret = $this->getLocalURL( $query, $query2 ) . $this->getFragmentForURL();
1397                 }
1398                 wfProfileOut( __METHOD__ );
1399                 return $ret;
1400         }
1401
1402         /**
1403          * Get an HTML-escaped version of the URL form, suitable for
1404          * using in a link, without a server name or fragment
1405          *
1406          * @param $query String an optional query string
1407          * @return String the URL
1408          */
1409         public function escapeLocalURL( $query = '', $query2 = false ) {
1410                 wfDeprecated( __METHOD__, '1.19' );
1411                 return htmlspecialchars( $this->getLocalURL( $query, $query2 ) );
1412         }
1413
1414         /**
1415          * Get an HTML-escaped version of the URL form, suitable for
1416          * using in a link, including the server name and fragment
1417          *
1418          * @param $query String an optional query string
1419          * @return String the URL
1420          */
1421         public function escapeFullURL( $query = '', $query2 = false ) {
1422                 wfDeprecated( __METHOD__, '1.19' );
1423                 return htmlspecialchars( $this->getFullURL( $query, $query2 ) );
1424         }
1425
1426         /**
1427          * Get the URL form for an internal link.
1428          * - Used in various Squid-related code, in case we have a different
1429          * internal hostname for the server from the exposed one.
1430          *
1431          * This uses $wgInternalServer to qualify the path, or $wgServer
1432          * if $wgInternalServer is not set. If the server variable used is
1433          * protocol-relative, the URL will be expanded to http://
1434          *
1435          * @param $query String an optional query string
1436          * @param $variant String language variant of url (for sr, zh..)
1437          * @return String the URL
1438          */
1439         public function getInternalURL( $query = '', $query2 = false ) {
1440                 global $wgInternalServer, $wgServer;
1441                 $query = self::fixUrlQueryArgs( $query, $query2 );
1442                 $server = $wgInternalServer !== false ? $wgInternalServer : $wgServer;
1443                 $url = wfExpandUrl( $server . $this->getLocalURL( $query ), PROTO_HTTP );
1444                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
1445                 return $url;
1446         }
1447
1448         /**
1449          * Get the URL for a canonical link, for use in things like IRC and
1450          * e-mail notifications. Uses $wgCanonicalServer and the
1451          * GetCanonicalURL hook.
1452          *
1453          * NOTE: Unlike getInternalURL(), the canonical URL includes the fragment
1454          *
1455          * @param $query string An optional query string
1456          * @param $variant string Language variant of URL (for sr, zh, ...)
1457          * @return string The URL
1458          * @since 1.18
1459          */
1460         public function getCanonicalURL( $query = '', $query2 = false ) {
1461                 $query = self::fixUrlQueryArgs( $query, $query2 );
1462                 $url = wfExpandUrl( $this->getLocalURL( $query, $variant ) . $this->getFragmentForURL(), PROTO_CANONICAL );
1463                 wfRunHooks( 'GetCanonicalURL', array( &$this, &$url, $query ) );
1464                 return $url;
1465         }
1466
1467         /**
1468          * HTML-escaped version of getCanonicalURL()
1469          * @since 1.18
1470          */
1471         public function escapeCanonicalURL( $query = '', $query2 = false ) {
1472                 wfDeprecated( __METHOD__, '1.19' );
1473                 return htmlspecialchars( $this->getCanonicalURL( $query, $query2 ) );
1474         }
1475
1476         /**
1477          * Get the edit URL for this Title
1478          *
1479          * @return String the URL, or a null string if this is an
1480          *  interwiki link
1481          */
1482         public function getEditURL() {
1483                 if ( $this->mInterwiki != '' ) {
1484                         return '';
1485                 }
1486                 $s = $this->getLocalURL( 'action=edit' );
1487
1488                 return $s;
1489         }
1490
1491         /**
1492          * Is $wgUser watching this page?
1493          *
1494          * @return Bool
1495          */
1496         public function userIsWatching() {
1497                 global $wgUser;
1498
1499                 if ( is_null( $this->mWatched ) ) {
1500                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn() ) {
1501                                 $this->mWatched = false;
1502                         } else {
1503                                 $this->mWatched = $wgUser->isWatched( $this );
1504                         }
1505                 }
1506                 return $this->mWatched;
1507         }
1508
1509         /**
1510          * Can $wgUser read this page?
1511          *
1512          * @deprecated in 1.19; use userCan(), quickUserCan() or getUserPermissionsErrors() instead
1513          * @return Bool
1514          * @todo fold these checks into userCan()
1515          */
1516         public function userCanRead() {
1517                 return $this->userCan( 'read' );
1518         }
1519
1520         /**
1521          * Can $user perform $action on this page?
1522          * This skips potentially expensive cascading permission checks
1523          * as well as avoids expensive error formatting
1524          *
1525          * Suitable for use for nonessential UI controls in common cases, but
1526          * _not_ for functional access control.
1527          *
1528          * May provide false positives, but should never provide a false negative.
1529          *
1530          * @param $action String action that permission needs to be checked for
1531          * @param $user User to check (since 1.19); $wgUser will be used if not
1532          *              provided.
1533          * @return Bool
1534          */
1535         public function quickUserCan( $action, $user = null ) {
1536                 return $this->userCan( $action, $user, false );
1537         }
1538
1539         /**
1540          * Can $user perform $action on this page?
1541          *
1542          * @param $action String action that permission needs to be checked for
1543          * @param $user User to check (since 1.19); $wgUser will be used if not
1544          *   provided.
1545          * @param $doExpensiveQueries Bool Set this to false to avoid doing
1546          *   unnecessary queries.
1547          * @return Bool
1548          */
1549         public function userCan( $action, $user = null, $doExpensiveQueries = true ) {
1550                 if ( !$user instanceof User ) {
1551                         global $wgUser;
1552                         $user = $wgUser;
1553                 }
1554                 return !count( $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries, true ) );
1555         }
1556
1557         /**
1558          * Can $user perform $action on this page?
1559          *
1560          * @todo FIXME: This *does not* check throttles (User::pingLimiter()).
1561          *
1562          * @param $action String action that permission needs to be checked for
1563          * @param $user User to check
1564          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary
1565          *   queries by skipping checks for cascading protections and user blocks.
1566          * @param $ignoreErrors Array of Strings Set this to a list of message keys
1567          *   whose corresponding errors may be ignored.
1568          * @return Array of arguments to wfMsg to explain permissions problems.
1569          */
1570         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1571                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1572
1573                 // Remove the errors being ignored.
1574                 foreach ( $errors as $index => $error ) {
1575                         $error_key = is_array( $error ) ? $error[0] : $error;
1576
1577                         if ( in_array( $error_key, $ignoreErrors ) ) {
1578                                 unset( $errors[$index] );
1579                         }
1580                 }
1581
1582                 return $errors;
1583         }
1584
1585         /**
1586          * Permissions checks that fail most often, and which are easiest to test.
1587          *
1588          * @param $action String the action to check
1589          * @param $user User user to check
1590          * @param $errors Array list of current errors
1591          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1592          * @param $short Boolean short circuit on first error
1593          *
1594          * @return Array list of errors
1595          */
1596         private function checkQuickPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1597                 if ( $action == 'create' ) {
1598                         if ( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1599                                  ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1600                                 $errors[] = $user->isAnon() ? array( 'nocreatetext' ) : array( 'nocreate-loggedin' );
1601                         }
1602                 } elseif ( $action == 'move' ) {
1603                         if ( !$user->isAllowed( 'move-rootuserpages' )
1604                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1605                                 // Show user page-specific message only if the user can move other pages
1606                                 $errors[] = array( 'cant-move-user-page' );
1607                         }
1608
1609                         // Check if user is allowed to move files if it's a file
1610                         if ( $this->mNamespace == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1611                                 $errors[] = array( 'movenotallowedfile' );
1612                         }
1613
1614                         if ( !$user->isAllowed( 'move' ) ) {
1615                                 // User can't move anything
1616                                 global $wgGroupPermissions;
1617                                 $userCanMove = false;
1618                                 if ( isset( $wgGroupPermissions['user']['move'] ) ) {
1619                                         $userCanMove = $wgGroupPermissions['user']['move'];
1620                                 }
1621                                 $autoconfirmedCanMove = false;
1622                                 if ( isset( $wgGroupPermissions['autoconfirmed']['move'] ) ) {
1623                                         $autoconfirmedCanMove = $wgGroupPermissions['autoconfirmed']['move'];
1624                                 }
1625                                 if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
1626                                         // custom message if logged-in users without any special rights can move
1627                                         $errors[] = array( 'movenologintext' );
1628                                 } else {
1629                                         $errors[] = array( 'movenotallowed' );
1630                                 }
1631                         }
1632                 } elseif ( $action == 'move-target' ) {
1633                         if ( !$user->isAllowed( 'move' ) ) {
1634                                 // User can't move anything
1635                                 $errors[] = array( 'movenotallowed' );
1636                         } elseif ( !$user->isAllowed( 'move-rootuserpages' )
1637                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1638                                 // Show user page-specific message only if the user can move other pages
1639                                 $errors[] = array( 'cant-move-to-user-page' );
1640                         }
1641                 } elseif ( !$user->isAllowed( $action ) ) {
1642                         $errors[] = $this->missingPermissionError( $action, $short );
1643                 }
1644
1645                 return $errors;
1646         }
1647
1648         /**
1649          * Add the resulting error code to the errors array
1650          *
1651          * @param $errors Array list of current errors
1652          * @param $result Mixed result of errors
1653          *
1654          * @return Array list of errors
1655          */
1656         private function resultToError( $errors, $result ) {
1657                 if ( is_array( $result ) && count( $result ) && !is_array( $result[0] ) ) {
1658                         // A single array representing an error
1659                         $errors[] = $result;
1660                 } elseif ( is_array( $result ) && is_array( $result[0] ) ) {
1661                         // A nested array representing multiple errors
1662                         $errors = array_merge( $errors, $result );
1663                 } elseif ( $result !== '' && is_string( $result ) ) {
1664                         // A string representing a message-id
1665                         $errors[] = array( $result );
1666                 } elseif ( $result === false ) {
1667                         // a generic "We don't want them to do that"
1668                         $errors[] = array( 'badaccess-group0' );
1669                 }
1670                 return $errors;
1671         }
1672
1673         /**
1674          * Check various permission hooks
1675          *
1676          * @param $action String the action to check
1677          * @param $user User user to check
1678          * @param $errors Array list of current errors
1679          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1680          * @param $short Boolean short circuit on first error
1681          *
1682          * @return Array list of errors
1683          */
1684         private function checkPermissionHooks( $action, $user, $errors, $doExpensiveQueries, $short ) {
1685                 // Use getUserPermissionsErrors instead
1686                 $result = '';
1687                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1688                         return $result ? array() : array( array( 'badaccess-group0' ) );
1689                 }
1690                 // Check getUserPermissionsErrors hook
1691                 if ( !wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1692                         $errors = $this->resultToError( $errors, $result );
1693                 }
1694                 // Check getUserPermissionsErrorsExpensive hook
1695                 if ( $doExpensiveQueries && !( $short && count( $errors ) > 0 ) &&
1696                          !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) ) ) {
1697                         $errors = $this->resultToError( $errors, $result );
1698                 }
1699
1700                 return $errors;
1701         }
1702
1703         /**
1704          * Check permissions on special pages & namespaces
1705          *
1706          * @param $action String the action to check
1707          * @param $user User user to check
1708          * @param $errors Array list of current errors
1709          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1710          * @param $short Boolean short circuit on first error
1711          *
1712          * @return Array list of errors
1713          */
1714         private function checkSpecialsAndNSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1715                 # Only 'createaccount' and 'execute' can be performed on
1716                 # special pages, which don't actually exist in the DB.
1717                 $specialOKActions = array( 'createaccount', 'execute', 'read' );
1718                 if ( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions ) ) {
1719                         $errors[] = array( 'ns-specialprotected' );
1720                 }
1721
1722                 # Check $wgNamespaceProtection for restricted namespaces
1723                 if ( $this->isNamespaceProtected( $user ) ) {
1724                         $ns = $this->mNamespace == NS_MAIN ?
1725                                 wfMsg( 'nstab-main' ) : $this->getNsText();
1726                         $errors[] = $this->mNamespace == NS_MEDIAWIKI ?
1727                                 array( 'protectedinterface' ) : array( 'namespaceprotected',  $ns );
1728                 }
1729
1730                 return $errors;
1731         }
1732
1733         /**
1734          * Check CSS/JS sub-page permissions
1735          *
1736          * @param $action String the action to check
1737          * @param $user User user to check
1738          * @param $errors Array list of current errors
1739          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1740          * @param $short Boolean short circuit on first error
1741          *
1742          * @return Array list of errors
1743          */
1744         private function checkCSSandJSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1745                 # Protect css/js subpages of user pages
1746                 # XXX: this might be better using restrictions
1747                 # XXX: right 'editusercssjs' is deprecated, for backward compatibility only
1748                 if ( $action != 'patrol' && !$user->isAllowed( 'editusercssjs' )
1749                                 && !preg_match( '/^' . preg_quote( $user->getName(), '/' ) . '\//', $this->mTextform ) ) {
1750                         if ( $this->isCssSubpage() && !$user->isAllowed( 'editusercss' ) ) {
1751                                 $errors[] = array( 'customcssprotected' );
1752                         } elseif ( $this->isJsSubpage() && !$user->isAllowed( 'edituserjs' ) ) {
1753                                 $errors[] = array( 'customjsprotected' );
1754                         }
1755                 }
1756
1757                 return $errors;
1758         }
1759
1760         /**
1761          * Check against page_restrictions table requirements on this
1762          * page. The user must possess all required rights for this
1763          * action.
1764          *
1765          * @param $action String the action to check
1766          * @param $user User user to check
1767          * @param $errors Array list of current errors
1768          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1769          * @param $short Boolean short circuit on first error
1770          *
1771          * @return Array list of errors
1772          */
1773         private function checkPageRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1774                 foreach ( $this->getRestrictions( $action ) as $right ) {
1775                         // Backwards compatibility, rewrite sysop -> protect
1776                         if ( $right == 'sysop' ) {
1777                                 $right = 'protect';
1778                         }
1779                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1780                                 // Users with 'editprotected' permission can edit protected pages
1781                                 // without cascading option turned on.
1782                                 if ( $action != 'edit' || !$user->isAllowed( 'editprotected' )
1783                                         || $this->mCascadeRestriction )
1784                                 {
1785                                         $errors[] = array( 'protectedpagetext', $right );
1786                                 }
1787                         }
1788                 }
1789
1790                 return $errors;
1791         }
1792
1793         /**
1794          * Check restrictions on cascading pages.
1795          *
1796          * @param $action String the action to check
1797          * @param $user User to check
1798          * @param $errors Array list of current errors
1799          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1800          * @param $short Boolean short circuit on first error
1801          *
1802          * @return Array list of errors
1803          */
1804         private function checkCascadingSourcesRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1805                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1806                         # We /could/ use the protection level on the source page, but it's
1807                         # fairly ugly as we have to establish a precedence hierarchy for pages
1808                         # included by multiple cascade-protected pages. So just restrict
1809                         # it to people with 'protect' permission, as they could remove the
1810                         # protection anyway.
1811                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1812                         # Cascading protection depends on more than this page...
1813                         # Several cascading protected pages may include this page...
1814                         # Check each cascading level
1815                         # This is only for protection restrictions, not for all actions
1816                         if ( isset( $restrictions[$action] ) ) {
1817                                 foreach ( $restrictions[$action] as $right ) {
1818                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1819                                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1820                                                 $pages = '';
1821                                                 foreach ( $cascadingSources as $page )
1822                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1823                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1824                                         }
1825                                 }
1826                         }
1827                 }
1828
1829                 return $errors;
1830         }
1831
1832         /**
1833          * Check action permissions not already checked in checkQuickPermissions
1834          *
1835          * @param $action String the action to check
1836          * @param $user User to check
1837          * @param $errors Array list of current errors
1838          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1839          * @param $short Boolean short circuit on first error
1840          *
1841          * @return Array list of errors
1842          */
1843         private function checkActionPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1844                 if ( $action == 'protect' ) {
1845                         if ( count( $this->getUserPermissionsErrorsInternal( 'edit', $user, $doExpensiveQueries, true ) ) ) {
1846                                 // If they can't edit, they shouldn't protect.
1847                                 $errors[] = array( 'protect-cantedit' );
1848                         }
1849                 } elseif ( $action == 'create' ) {
1850                         $title_protection = $this->getTitleProtection();
1851                         if( $title_protection ) {
1852                                 if( $title_protection['pt_create_perm'] == 'sysop' ) {
1853                                         $title_protection['pt_create_perm'] = 'protect'; // B/C
1854                                 }
1855                                 if( $title_protection['pt_create_perm'] == '' ||
1856                                         !$user->isAllowed( $title_protection['pt_create_perm'] ) )
1857                                 {
1858                                         $errors[] = array( 'titleprotected', User::whoIs( $title_protection['pt_user'] ), $title_protection['pt_reason'] );
1859                                 }
1860                         }
1861                 } elseif ( $action == 'move' ) {
1862                         // Check for immobile pages
1863                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1864                                 // Specific message for this case
1865                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1866                         } elseif ( !$this->isMovable() ) {
1867                                 // Less specific message for rarer cases
1868                                 $errors[] = array( 'immobile-source-page' );
1869                         }
1870                 } elseif ( $action == 'move-target' ) {
1871                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1872                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1873                         } elseif ( !$this->isMovable() ) {
1874                                 $errors[] = array( 'immobile-target-page' );
1875                         }
1876                 }
1877                 return $errors;
1878         }
1879
1880         /**
1881          * Check that the user isn't blocked from editting.
1882          *
1883          * @param $action String the action to check
1884          * @param $user User to check
1885          * @param $errors Array list of current errors
1886          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1887          * @param $short Boolean short circuit on first error
1888          *
1889          * @return Array list of errors
1890          */
1891         private function checkUserBlock( $action, $user, $errors, $doExpensiveQueries, $short ) {
1892                 // Account creation blocks handled at userlogin.
1893                 // Unblocking handled in SpecialUnblock
1894                 if( !$doExpensiveQueries || in_array( $action, array( 'createaccount', 'unblock' ) ) ) {
1895                         return $errors;
1896                 }
1897
1898                 global $wgContLang, $wgLang, $wgEmailConfirmToEdit;
1899
1900                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() ) {
1901                         $errors[] = array( 'confirmedittext' );
1902                 }
1903
1904                 if ( ( $action == 'edit' || $action == 'create' ) && !$user->isBlockedFrom( $this ) ) {
1905                         // Don't block the user from editing their own talk page unless they've been
1906                         // explicitly blocked from that too.
1907                 } elseif( $user->isBlocked() && $user->mBlock->prevents( $action ) !== false ) {
1908                         $block = $user->mBlock;
1909
1910                         // This is from OutputPage::blockedPage
1911                         // Copied at r23888 by werdna
1912
1913                         $id = $user->blockedBy();
1914                         $reason = $user->blockedFor();
1915                         if ( $reason == '' ) {
1916                                 $reason = wfMsg( 'blockednoreason' );
1917                         }
1918                         $ip = $user->getRequest()->getIP();
1919
1920                         if ( is_numeric( $id ) ) {
1921                                 $name = User::whoIs( $id );
1922                         } else {
1923                                 $name = $id;
1924                         }
1925
1926                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1927                         $blockid = $block->getId();
1928                         $blockExpiry = $user->mBlock->mExpiry;
1929                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $user->mBlock->mTimestamp ), true );
1930                         if ( $blockExpiry == 'infinity' ) {
1931                                 $blockExpiry = wfMessage( 'infiniteblock' )->text();
1932                         } else {
1933                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1934                         }
1935
1936                         $intended = strval( $user->mBlock->getTarget() );
1937
1938                         $errors[] = array( ( $block->mAuto ? 'autoblockedtext' : 'blockedtext' ), $link, $reason, $ip, $name,
1939                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
1940                 }
1941
1942                 return $errors;
1943         }
1944
1945         /**
1946          * Check that the user is allowed to read this page.
1947          *
1948          * @param $action String the action to check
1949          * @param $user User to check
1950          * @param $errors Array list of current errors
1951          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1952          * @param $short Boolean short circuit on first error
1953          *
1954          * @return Array list of errors
1955          */
1956         private function checkReadPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1957                 static $useShortcut = null;
1958
1959                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
1960                 if ( is_null( $useShortcut ) ) {
1961                         global $wgGroupPermissions, $wgRevokePermissions;
1962                         $useShortcut = true;
1963                         if ( empty( $wgGroupPermissions['*']['read'] ) ) {
1964                                 # Not a public wiki, so no shortcut
1965                                 $useShortcut = false;
1966                         } elseif ( !empty( $wgRevokePermissions ) ) {
1967                                 /**
1968                                  * Iterate through each group with permissions being revoked (key not included since we don't care
1969                                  * what the group name is), then check if the read permission is being revoked. If it is, then
1970                                  * we don't use the shortcut below since the user might not be able to read, even though anon
1971                                  * reading is allowed.
1972                                  */
1973                                 foreach ( $wgRevokePermissions as $perms ) {
1974                                         if ( !empty( $perms['read'] ) ) {
1975                                                 # We might be removing the read right from the user, so no shortcut
1976                                                 $useShortcut = false;
1977                                                 break;
1978                                         }
1979                                 }
1980                         }
1981                 }
1982
1983                 # Shortcut for public wikis, allows skipping quite a bit of code
1984                 if ( $useShortcut ) {
1985                         return $errors;
1986                 }
1987
1988                 # If the user is allowed to read pages, he is allowed to read all pages
1989                 if ( $user->isAllowed( 'read' ) ) {
1990                         return $errors;
1991                 }
1992
1993                 # Always grant access to the login page.
1994                 # Even anons need to be able to log in.
1995                 if ( $this->isSpecial( 'Userlogin' )
1996                         || $this->isSpecial( 'ChangePassword' )
1997                         || $this->isSpecial( 'PasswordReset' )
1998                 ) {
1999                         return $errors;
2000                 }
2001
2002                 # Time to check the whitelist
2003                 global $wgWhitelistRead;
2004
2005                 # Only to these checks is there's something to check against
2006                 if ( is_array( $wgWhitelistRead ) && count( $wgWhitelistRead ) ) {
2007                         # Check for explicit whitelisting
2008                         $name = $this->getPrefixedText();
2009                         $dbName = $this->getPrefixedDBKey();
2010
2011                         // Check with and without underscores
2012                         if ( in_array( $name, $wgWhitelistRead, true ) || in_array( $dbName, $wgWhitelistRead, true ) ) {
2013                                 return $errors;
2014                         }
2015
2016                         # Old settings might have the title prefixed with
2017                         # a colon for main-namespace pages
2018                         if ( $this->getNamespace() == NS_MAIN ) {
2019                                 if ( in_array( ':' . $name, $wgWhitelistRead ) ) {
2020                                         return $errors;
2021                                 }
2022                         }
2023
2024                         # If it's a special page, ditch the subpage bit and check again
2025                         if ( $this->isSpecialPage() ) {
2026                                 $name = $this->getDBkey();
2027                                 list( $name, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $name );
2028                                 if ( $name !== false ) {
2029                                         $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
2030                                         if ( in_array( $pure, $wgWhitelistRead, true ) ) {
2031                                                 return $errors;
2032                                         }
2033                                 }
2034                         }
2035                 }
2036
2037                 $errors[] = $this->missingPermissionError( $action, $short );
2038                 return $errors;
2039         }
2040
2041         /**
2042          * Get a description array when the user doesn't have the right to perform
2043          * $action (i.e. when User::isAllowed() returns false)
2044          *
2045          * @param $action String the action to check
2046          * @param $short Boolean short circuit on first error
2047          * @return Array list of errors
2048          */
2049         private function missingPermissionError( $action, $short ) {
2050                 // We avoid expensive display logic for quickUserCan's and such
2051                 if ( $short ) {
2052                         return array( 'badaccess-group0' );
2053                 }
2054
2055                 $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
2056                         User::getGroupsWithPermission( $action ) );
2057
2058                 if ( count( $groups ) ) {
2059                         global $wgLang;
2060                         return array(
2061                                 'badaccess-groups',
2062                                 $wgLang->commaList( $groups ),
2063                                 count( $groups )
2064                         );
2065                 } else {
2066                         return array( 'badaccess-group0' );
2067                 }
2068         }
2069
2070         /**
2071          * Can $user perform $action on this page? This is an internal function,
2072          * which checks ONLY that previously checked by userCan (i.e. it leaves out
2073          * checks on wfReadOnly() and blocks)
2074          *
2075          * @param $action String action that permission needs to be checked for
2076          * @param $user User to check
2077          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary queries.
2078          * @param $short Bool Set this to true to stop after the first permission error.
2079          * @return Array of arrays of the arguments to wfMsg to explain permissions problems.
2080          */
2081         protected function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true, $short = false ) {
2082                 wfProfileIn( __METHOD__ );
2083
2084                 # Read has special handling
2085                 if ( $action == 'read' ) {
2086                         $checks = array(
2087                                 'checkPermissionHooks',
2088                                 'checkReadPermissions',
2089                         );
2090                 } else {
2091                         $checks = array(
2092                                 'checkQuickPermissions',
2093                                 'checkPermissionHooks',
2094                                 'checkSpecialsAndNSPermissions',
2095                                 'checkCSSandJSPermissions',
2096                                 'checkPageRestrictions',
2097                                 'checkCascadingSourcesRestrictions',
2098                                 'checkActionPermissions',
2099                                 'checkUserBlock'
2100                         );
2101                 }
2102
2103                 $errors = array();
2104                 while( count( $checks ) > 0 &&
2105                                 !( $short && count( $errors ) > 0 ) ) {
2106                         $method = array_shift( $checks );
2107                         $errors = $this->$method( $action, $user, $errors, $doExpensiveQueries, $short );
2108                 }
2109
2110                 wfProfileOut( __METHOD__ );
2111                 return $errors;
2112         }
2113
2114         /**
2115          * Protect css subpages of user pages: can $wgUser edit
2116          * this page?
2117          *
2118          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2119          * @return Bool
2120          */
2121         public function userCanEditCssSubpage() {
2122                 global $wgUser;
2123                 wfDeprecated( __METHOD__ );
2124                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'editusercss' ) )
2125                         || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2126         }
2127
2128         /**
2129          * Protect js subpages of user pages: can $wgUser edit
2130          * this page?
2131          *
2132          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2133          * @return Bool
2134          */
2135         public function userCanEditJsSubpage() {
2136                 global $wgUser;
2137                 wfDeprecated( __METHOD__ );
2138                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'edituserjs' ) )
2139                            || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2140         }
2141
2142         /**
2143          * Get a filtered list of all restriction types supported by this wiki.
2144          * @param bool $exists True to get all restriction types that apply to
2145          * titles that do exist, False for all restriction types that apply to
2146          * titles that do not exist
2147          * @return array
2148          */
2149         public static function getFilteredRestrictionTypes( $exists = true ) {
2150                 global $wgRestrictionTypes;
2151                 $types = $wgRestrictionTypes;
2152                 if ( $exists ) {
2153                         # Remove the create restriction for existing titles
2154                         $types = array_diff( $types, array( 'create' ) );
2155                 } else {
2156                         # Only the create and upload restrictions apply to non-existing titles
2157                         $types = array_intersect( $types, array( 'create', 'upload' ) );
2158                 }
2159                 return $types;
2160         }
2161
2162         /**
2163          * Returns restriction types for the current Title
2164          *
2165          * @return array applicable restriction types
2166          */
2167         public function getRestrictionTypes() {
2168                 if ( $this->isSpecialPage() ) {
2169                         return array();
2170                 }
2171
2172                 $types = self::getFilteredRestrictionTypes( $this->exists() );
2173
2174                 if ( $this->getNamespace() != NS_FILE ) {
2175                         # Remove the upload restriction for non-file titles
2176                         $types = array_diff( $types, array( 'upload' ) );
2177                 }
2178
2179                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
2180
2181                 wfDebug( __METHOD__ . ': applicable restrictions to [[' .
2182                         $this->getPrefixedText() . ']] are {' . implode( ',', $types ) . "}\n" );
2183
2184                 return $types;
2185         }
2186
2187         /**
2188          * Is this title subject to title protection?
2189          * Title protection is the one applied against creation of such title.
2190          *
2191          * @return Mixed An associative array representing any existent title
2192          *   protection, or false if there's none.
2193          */
2194         private function getTitleProtection() {
2195                 // Can't protect pages in special namespaces
2196                 if ( $this->getNamespace() < 0 ) {
2197                         return false;
2198                 }
2199
2200                 // Can't protect pages that exist.
2201                 if ( $this->exists() ) {
2202                         return false;
2203                 }
2204
2205                 if ( !isset( $this->mTitleProtection ) ) {
2206                         $dbr = wfGetDB( DB_SLAVE );
2207                         $res = $dbr->select( 'protected_titles', '*',
2208                                 array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2209                                 __METHOD__ );
2210
2211                         // fetchRow returns false if there are no rows.
2212                         $this->mTitleProtection = $dbr->fetchRow( $res );
2213                 }
2214                 return $this->mTitleProtection;
2215         }
2216
2217         /**
2218          * Update the title protection status
2219          *
2220          * @param $create_perm String Permission required for creation
2221          * @param $reason String Reason for protection
2222          * @param $expiry String Expiry timestamp
2223          * @return boolean true
2224          */
2225         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
2226                 global $wgUser, $wgContLang;
2227
2228                 if ( $create_perm == implode( ',', $this->getRestrictions( 'create' ) )
2229                         && $expiry == $this->mRestrictionsExpiry['create'] ) {
2230                         // No change
2231                         return true;
2232                 }
2233
2234                 list ( $namespace, $title ) = array( $this->getNamespace(), $this->getDBkey() );
2235
2236                 $dbw = wfGetDB( DB_MASTER );
2237
2238                 $encodedExpiry = $dbw->encodeExpiry( $expiry );
2239
2240                 $expiry_description = '';
2241                 if ( $encodedExpiry != $dbw->getInfinity() ) {
2242                         $expiry_description = ' (' . wfMsgForContent( 'protect-expiring', $wgContLang->timeanddate( $expiry ),
2243                                 $wgContLang->date( $expiry ) , $wgContLang->time( $expiry ) ) . ')';
2244                 } else {
2245                         $expiry_description .= ' (' . wfMsgForContent( 'protect-expiry-indefinite' ) . ')';
2246                 }
2247
2248                 # Update protection table
2249                 if ( $create_perm != '' ) {
2250                         $this->mTitleProtection = array(
2251                                         'pt_namespace' => $namespace,
2252                                         'pt_title' => $title,
2253                                         'pt_create_perm' => $create_perm,
2254                                         'pt_timestamp' => $dbw->encodeExpiry( wfTimestampNow() ),
2255                                         'pt_expiry' => $encodedExpiry,
2256                                         'pt_user' => $wgUser->getId(),
2257                                         'pt_reason' => $reason,
2258                                 );
2259                         $dbw->replace( 'protected_titles', array( array( 'pt_namespace', 'pt_title' ) ),
2260                                 $this->mTitleProtection, __METHOD__     );
2261                 } else {
2262                         $dbw->delete( 'protected_titles', array( 'pt_namespace' => $namespace,
2263                                 'pt_title' => $title ), __METHOD__ );
2264                         $this->mTitleProtection = false;
2265                 }
2266
2267                 # Update the protection log
2268                 if ( $dbw->affectedRows() ) {
2269                         $log = new LogPage( 'protect' );
2270
2271                         if ( $create_perm ) {
2272                                 $params = array( "[create=$create_perm] $expiry_description", '' );
2273                                 $log->addEntry( ( isset( $this->mRestrictions['create'] ) && $this->mRestrictions['create'] ) ? 'modify' : 'protect', $this, trim( $reason ), $params );
2274                         } else {
2275                                 $log->addEntry( 'unprotect', $this, $reason );
2276                         }
2277                 }
2278
2279                 return true;
2280         }
2281
2282         /**
2283          * Remove any title protection due to page existing
2284          */
2285         public function deleteTitleProtection() {
2286                 $dbw = wfGetDB( DB_MASTER );
2287
2288                 $dbw->delete(
2289                         'protected_titles',
2290                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2291                         __METHOD__
2292                 );
2293                 $this->mTitleProtection = false;
2294         }
2295
2296         /**
2297          * Is this page "semi-protected" - the *only* protection is autoconfirm?
2298          *
2299          * @param $action String Action to check (default: edit)
2300          * @return Bool
2301          */
2302         public function isSemiProtected( $action = 'edit' ) {
2303                 if ( $this->exists() ) {
2304                         $restrictions = $this->getRestrictions( $action );
2305                         if ( count( $restrictions ) > 0 ) {
2306                                 foreach ( $restrictions as $restriction ) {
2307                                         if ( strtolower( $restriction ) != 'autoconfirmed' ) {
2308                                                 return false;
2309                                         }
2310                                 }
2311                         } else {
2312                                 # Not protected
2313                                 return false;
2314                         }
2315                         return true;
2316                 } else {
2317                         # If it doesn't exist, it can't be protected
2318                         return false;
2319                 }
2320         }
2321
2322         /**
2323          * Does the title correspond to a protected article?
2324          *
2325          * @param $action String the action the page is protected from,
2326          * by default checks all actions.
2327          * @return Bool
2328          */
2329         public function isProtected( $action = '' ) {
2330                 global $wgRestrictionLevels;
2331
2332                 $restrictionTypes = $this->getRestrictionTypes();
2333
2334                 # Special pages have inherent protection
2335                 if( $this->isSpecialPage() ) {
2336                         return true;
2337                 }
2338
2339                 # Check regular protection levels
2340                 foreach ( $restrictionTypes as $type ) {
2341                         if ( $action == $type || $action == '' ) {
2342                                 $r = $this->getRestrictions( $type );
2343                                 foreach ( $wgRestrictionLevels as $level ) {
2344                                         if ( in_array( $level, $r ) && $level != '' ) {
2345                                                 return true;
2346                                         }
2347                                 }
2348                         }
2349                 }
2350
2351                 return false;
2352         }
2353
2354         /**
2355          * Determines if $user is unable to edit this page because it has been protected
2356          * by $wgNamespaceProtection.
2357          *
2358          * @param $user User object to check permissions
2359          * @return Bool
2360          */
2361         public function isNamespaceProtected( User $user ) {
2362                 global $wgNamespaceProtection;
2363
2364                 if ( isset( $wgNamespaceProtection[$this->mNamespace] ) ) {
2365                         foreach ( (array)$wgNamespaceProtection[$this->mNamespace] as $right ) {
2366                                 if ( $right != '' && !$user->isAllowed( $right ) ) {
2367                                         return true;
2368                                 }
2369                         }
2370                 }
2371                 return false;
2372         }
2373
2374         /**
2375          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
2376          *
2377          * @return Bool If the page is subject to cascading restrictions.
2378          */
2379         public function isCascadeProtected() {
2380                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
2381                 return ( $sources > 0 );
2382         }
2383
2384         /**
2385          * Cascading protection: Get the source of any cascading restrictions on this page.
2386          *
2387          * @param $getPages Bool Whether or not to retrieve the actual pages
2388          *        that the restrictions have come from.
2389          * @return Mixed Array of Title objects of the pages from which cascading restrictions
2390          *     have come, false for none, or true if such restrictions exist, but $getPages
2391          *     was not set.  The restriction array is an array of each type, each of which
2392          *     contains a array of unique groups.
2393          */
2394         public function getCascadeProtectionSources( $getPages = true ) {
2395                 global $wgContLang;
2396                 $pagerestrictions = array();
2397
2398                 if ( isset( $this->mCascadeSources ) && $getPages ) {
2399                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
2400                 } elseif ( isset( $this->mHasCascadingRestrictions ) && !$getPages ) {
2401                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
2402                 }
2403
2404                 wfProfileIn( __METHOD__ );
2405
2406                 $dbr = wfGetDB( DB_SLAVE );
2407
2408                 if ( $this->getNamespace() == NS_FILE ) {
2409                         $tables = array( 'imagelinks', 'page_restrictions' );
2410                         $where_clauses = array(
2411                                 'il_to' => $this->getDBkey(),
2412                                 'il_from=pr_page',
2413                                 'pr_cascade' => 1
2414                         );
2415                 } else {
2416                         $tables = array( 'templatelinks', 'page_restrictions' );
2417                         $where_clauses = array(
2418                                 'tl_namespace' => $this->getNamespace(),
2419                                 'tl_title' => $this->getDBkey(),
2420                                 'tl_from=pr_page',
2421                                 'pr_cascade' => 1
2422                         );
2423                 }
2424
2425                 if ( $getPages ) {
2426                         $cols = array( 'pr_page', 'page_namespace', 'page_title',
2427                                                    'pr_expiry', 'pr_type', 'pr_level' );
2428                         $where_clauses[] = 'page_id=pr_page';
2429                         $tables[] = 'page';
2430                 } else {
2431                         $cols = array( 'pr_expiry' );
2432                 }
2433
2434                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
2435
2436                 $sources = $getPages ? array() : false;
2437                 $now = wfTimestampNow();
2438                 $purgeExpired = false;
2439
2440                 foreach ( $res as $row ) {
2441                         $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2442                         if ( $expiry > $now ) {
2443                                 if ( $getPages ) {
2444                                         $page_id = $row->pr_page;
2445                                         $page_ns = $row->page_namespace;
2446                                         $page_title = $row->page_title;
2447                                         $sources[$page_id] = Title::makeTitle( $page_ns, $page_title );
2448                                         # Add groups needed for each restriction type if its not already there
2449                                         # Make sure this restriction type still exists
2450
2451                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
2452                                                 $pagerestrictions[$row->pr_type] = array();
2453                                         }
2454
2455                                         if ( isset( $pagerestrictions[$row->pr_type] ) &&
2456                                                  !in_array( $row->pr_level, $pagerestrictions[$row->pr_type] ) ) {
2457                                                 $pagerestrictions[$row->pr_type][] = $row->pr_level;
2458                                         }
2459                                 } else {
2460                                         $sources = true;
2461                                 }
2462                         } else {
2463                                 // Trigger lazy purge of expired restrictions from the db
2464                                 $purgeExpired = true;
2465                         }
2466                 }
2467                 if ( $purgeExpired ) {
2468                         Title::purgeExpiredRestrictions();
2469                 }
2470
2471                 if ( $getPages ) {
2472                         $this->mCascadeSources = $sources;
2473                         $this->mCascadingRestrictions = $pagerestrictions;
2474                 } else {
2475                         $this->mHasCascadingRestrictions = $sources;
2476                 }
2477
2478                 wfProfileOut( __METHOD__ );
2479                 return array( $sources, $pagerestrictions );
2480         }
2481
2482         /**
2483          * Accessor/initialisation for mRestrictions
2484          *
2485          * @param $action String action that permission needs to be checked for
2486          * @return Array of Strings the array of groups allowed to edit this article
2487          */
2488         public function getRestrictions( $action ) {
2489                 if ( !$this->mRestrictionsLoaded ) {
2490                         $this->loadRestrictions();
2491                 }
2492                 return isset( $this->mRestrictions[$action] )
2493                                 ? $this->mRestrictions[$action]
2494                                 : array();
2495         }
2496
2497         /**
2498          * Get the expiry time for the restriction against a given action
2499          *
2500          * @return String|Bool 14-char timestamp, or 'infinity' if the page is protected forever
2501          *      or not protected at all, or false if the action is not recognised.
2502          */
2503         public function getRestrictionExpiry( $action ) {
2504                 if ( !$this->mRestrictionsLoaded ) {
2505                         $this->loadRestrictions();
2506                 }
2507                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2508         }
2509
2510         /**
2511          * Returns cascading restrictions for the current article
2512          *
2513          * @return Boolean
2514          */
2515         function areRestrictionsCascading() {
2516                 if ( !$this->mRestrictionsLoaded ) {
2517                         $this->loadRestrictions();
2518                 }
2519
2520                 return $this->mCascadeRestriction;
2521         }
2522
2523         /**
2524          * Loads a string into mRestrictions array
2525          *
2526          * @param $res Resource restrictions as an SQL result.
2527          * @param $oldFashionedRestrictions String comma-separated list of page
2528          *        restrictions from page table (pre 1.10)
2529          */
2530         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
2531                 $rows = array();
2532
2533                 foreach ( $res as $row ) {
2534                         $rows[] = $row;
2535                 }
2536
2537                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
2538         }
2539
2540         /**
2541          * Compiles list of active page restrictions from both page table (pre 1.10)
2542          * and page_restrictions table for this existing page.
2543          * Public for usage by LiquidThreads.
2544          *
2545          * @param $rows array of db result objects
2546          * @param $oldFashionedRestrictions string comma-separated list of page
2547          *        restrictions from page table (pre 1.10)
2548          */
2549         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
2550                 global $wgContLang;
2551                 $dbr = wfGetDB( DB_SLAVE );
2552
2553                 $restrictionTypes = $this->getRestrictionTypes();
2554
2555                 foreach ( $restrictionTypes as $type ) {
2556                         $this->mRestrictions[$type] = array();
2557                         $this->mRestrictionsExpiry[$type] = $wgContLang->formatExpiry( '', TS_MW );
2558                 }
2559
2560                 $this->mCascadeRestriction = false;
2561
2562                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2563
2564                 if ( $oldFashionedRestrictions === null ) {
2565                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2566                                 array( 'page_id' => $this->getArticleId() ), __METHOD__ );
2567                 }
2568
2569                 if ( $oldFashionedRestrictions != '' ) {
2570
2571                         foreach ( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2572                                 $temp = explode( '=', trim( $restrict ) );
2573                                 if ( count( $temp ) == 1 ) {
2574                                         // old old format should be treated as edit/move restriction
2575                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2576                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2577                                 } else {
2578                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
2579                                 }
2580                         }
2581
2582                         $this->mOldRestrictions = true;
2583
2584                 }
2585
2586                 if ( count( $rows ) ) {
2587                         # Current system - load second to make them override.
2588                         $now = wfTimestampNow();
2589                         $purgeExpired = false;
2590
2591                         # Cycle through all the restrictions.
2592                         foreach ( $rows as $row ) {
2593
2594                                 // Don't take care of restrictions types that aren't allowed
2595                                 if ( !in_array( $row->pr_type, $restrictionTypes ) )
2596                                         continue;
2597
2598                                 // This code should be refactored, now that it's being used more generally,
2599                                 // But I don't really see any harm in leaving it in Block for now -werdna
2600                                 $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2601
2602                                 // Only apply the restrictions if they haven't expired!
2603                                 if ( !$expiry || $expiry > $now ) {
2604                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2605                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2606
2607                                         $this->mCascadeRestriction |= $row->pr_cascade;
2608                                 } else {
2609                                         // Trigger a lazy purge of expired restrictions
2610                                         $purgeExpired = true;
2611                                 }
2612                         }
2613
2614                         if ( $purgeExpired ) {
2615                                 Title::purgeExpiredRestrictions();
2616                         }
2617                 }
2618
2619                 $this->mRestrictionsLoaded = true;
2620         }
2621
2622         /**
2623          * Load restrictions from the page_restrictions table
2624          *
2625          * @param $oldFashionedRestrictions String comma-separated list of page
2626          *        restrictions from page table (pre 1.10)
2627          */
2628         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2629                 global $wgContLang;
2630                 if ( !$this->mRestrictionsLoaded ) {
2631                         if ( $this->exists() ) {
2632                                 $dbr = wfGetDB( DB_SLAVE );
2633
2634                                 $res = $dbr->select(
2635                                         'page_restrictions',
2636                                         '*',
2637                                         array( 'pr_page' => $this->getArticleId() ),
2638                                         __METHOD__
2639                                 );
2640
2641                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2642                         } else {
2643                                 $title_protection = $this->getTitleProtection();
2644
2645                                 if ( $title_protection ) {
2646                                         $now = wfTimestampNow();
2647                                         $expiry = $wgContLang->formatExpiry( $title_protection['pt_expiry'], TS_MW );
2648
2649                                         if ( !$expiry || $expiry > $now ) {
2650                                                 // Apply the restrictions
2651                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2652                                                 $this->mRestrictions['create'] = explode( ',', trim( $title_protection['pt_create_perm'] ) );
2653                                         } else { // Get rid of the old restrictions
2654                                                 Title::purgeExpiredRestrictions();
2655                                                 $this->mTitleProtection = false;
2656                                         }
2657                                 } else {
2658                                         $this->mRestrictionsExpiry['create'] = $wgContLang->formatExpiry( '', TS_MW );
2659                                 }
2660                                 $this->mRestrictionsLoaded = true;
2661                         }
2662                 }
2663         }
2664
2665         /**
2666          * Purge expired restrictions from the page_restrictions table
2667          */
2668         static function purgeExpiredRestrictions() {
2669                 $dbw = wfGetDB( DB_MASTER );
2670                 $dbw->delete(
2671                         'page_restrictions',
2672                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2673                         __METHOD__
2674                 );
2675
2676                 $dbw->delete(
2677                         'protected_titles',
2678                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2679                         __METHOD__
2680                 );
2681         }
2682
2683         /**
2684          * Does this have subpages?  (Warning, usually requires an extra DB query.)
2685          *
2686          * @return Bool
2687          */
2688         public function hasSubpages() {
2689                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
2690                         # Duh
2691                         return false;
2692                 }
2693
2694                 # We dynamically add a member variable for the purpose of this method
2695                 # alone to cache the result.  There's no point in having it hanging
2696                 # around uninitialized in every Title object; therefore we only add it
2697                 # if needed and don't declare it statically.
2698                 if ( isset( $this->mHasSubpages ) ) {
2699                         return $this->mHasSubpages;
2700                 }
2701
2702                 $subpages = $this->getSubpages( 1 );
2703                 if ( $subpages instanceof TitleArray ) {
2704                         return $this->mHasSubpages = (bool)$subpages->count();
2705                 }
2706                 return $this->mHasSubpages = false;
2707         }
2708
2709         /**
2710          * Get all subpages of this page.
2711          *
2712          * @param $limit Int maximum number of subpages to fetch; -1 for no limit
2713          * @return mixed TitleArray, or empty array if this page's namespace
2714          *  doesn't allow subpages
2715          */
2716         public function getSubpages( $limit = -1 ) {
2717                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
2718                         return array();
2719                 }
2720
2721                 $dbr = wfGetDB( DB_SLAVE );
2722                 $conds['page_namespace'] = $this->getNamespace();
2723                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
2724                 $options = array();
2725                 if ( $limit > -1 ) {
2726                         $options['LIMIT'] = $limit;
2727                 }
2728                 return $this->mSubpages = TitleArray::newFromResult(
2729                         $dbr->select( 'page',
2730                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
2731                                 $conds,
2732                                 __METHOD__,
2733                                 $options
2734                         )
2735                 );
2736         }
2737
2738         /**
2739          * Is there a version of this page in the deletion archive?
2740          *
2741          * @return Int the number of archived revisions
2742          */
2743         public function isDeleted() {
2744                 if ( $this->getNamespace() < 0 ) {
2745                         $n = 0;
2746                 } else {
2747                         $dbr = wfGetDB( DB_SLAVE );
2748
2749                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2750                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2751                                 __METHOD__
2752                         );
2753                         if ( $this->getNamespace() == NS_FILE ) {
2754                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2755                                         array( 'fa_name' => $this->getDBkey() ),
2756                                         __METHOD__
2757                                 );
2758                         }
2759                 }
2760                 return (int)$n;
2761         }
2762
2763         /**
2764          * Is there a version of this page in the deletion archive?
2765          *
2766          * @return Boolean
2767          */
2768         public function isDeletedQuick() {
2769                 if ( $this->getNamespace() < 0 ) {
2770                         return false;
2771                 }
2772                 $dbr = wfGetDB( DB_SLAVE );
2773                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2774                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2775                         __METHOD__
2776                 );
2777                 if ( !$deleted && $this->getNamespace() == NS_FILE ) {
2778                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2779                                 array( 'fa_name' => $this->getDBkey() ),
2780                                 __METHOD__
2781                         );
2782                 }
2783                 return $deleted;
2784         }
2785
2786         /**
2787          * Get the number of views of this page
2788          *
2789          * @return int The view count for the page
2790          */
2791         public function getCount() {
2792                 if ( $this->mCounter == -1 ) {
2793                         if ( $this->exists() ) {
2794                                 $dbr = wfGetDB( DB_SLAVE );
2795                                 $this->mCounter = $dbr->selectField( 'page',
2796                                         'page_counter',
2797                                         array( 'page_id' => $this->getArticleID() ),
2798                                         __METHOD__
2799                                 );
2800                         } else {
2801                                 $this->mCounter = 0;
2802                         }
2803                 }
2804
2805                 return $this->mCounter;
2806         }
2807
2808         /**
2809          * Get the article ID for this Title from the link cache,
2810          * adding it if necessary
2811          *
2812          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select
2813          *  for update
2814          * @return Int the ID
2815          */
2816         public function getArticleID( $flags = 0 ) {
2817                 if ( $this->getNamespace() < 0 ) {
2818                         return $this->mArticleID = 0;
2819                 }
2820                 $linkCache = LinkCache::singleton();
2821                 if ( $flags & self::GAID_FOR_UPDATE ) {
2822                         $oldUpdate = $linkCache->forUpdate( true );
2823                         $linkCache->clearLink( $this );
2824                         $this->mArticleID = $linkCache->addLinkObj( $this );
2825                         $linkCache->forUpdate( $oldUpdate );
2826                 } else {
2827                         if ( -1 == $this->mArticleID ) {
2828                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2829                         }
2830                 }
2831                 return $this->mArticleID;
2832         }
2833
2834         /**
2835          * Is this an article that is a redirect page?
2836          * Uses link cache, adding it if necessary
2837          *
2838          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2839          * @return Bool
2840          */
2841         public function isRedirect( $flags = 0 ) {
2842                 if ( !is_null( $this->mRedirect ) ) {
2843                         return $this->mRedirect;
2844                 }
2845                 # Calling getArticleID() loads the field from cache as needed
2846                 if ( !$this->getArticleID( $flags ) ) {
2847                         return $this->mRedirect = false;
2848                 }
2849                 $linkCache = LinkCache::singleton();
2850                 $this->mRedirect = (bool)$linkCache->getGoodLinkFieldObj( $this, 'redirect' );
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                 $this->mLength = intval( $linkCache->getGoodLinkFieldObj( $this, 'length' ) );
2872
2873                 return $this->mLength;
2874         }
2875
2876         /**
2877          * What is the page_latest field for this page?
2878          *
2879          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2880          * @return Int or 0 if the page doesn't exist
2881          */
2882         public function getLatestRevID( $flags = 0 ) {
2883                 if ( $this->mLatestID !== false ) {
2884                         return intval( $this->mLatestID );
2885                 }
2886                 # Calling getArticleID() loads the field from cache as needed
2887                 if ( !$this->getArticleID( $flags ) ) {
2888                         return $this->mLatestID = 0;
2889                 }
2890                 $linkCache = LinkCache::singleton();
2891                 $this->mLatestID = intval( $linkCache->getGoodLinkFieldObj( $this, 'revision' ) );
2892
2893                 return $this->mLatestID;
2894         }
2895
2896         /**
2897          * This clears some fields in this object, and clears any associated
2898          * keys in the "bad links" section of the link cache.
2899          *
2900          * - This is called from Article::doEdit() and Article::insertOn() to allow
2901          * loading of the new page_id. It's also called from
2902          * Article::doDeleteArticle()
2903          *
2904          * @param $newid Int the new Article ID
2905          */
2906         public function resetArticleID( $newid ) {
2907                 $linkCache = LinkCache::singleton();
2908                 $linkCache->clearLink( $this );
2909
2910                 if ( $newid === false ) {
2911                         $this->mArticleID = -1;
2912                 } else {
2913                         $this->mArticleID = intval( $newid );
2914                 }
2915                 $this->mRestrictionsLoaded = false;
2916                 $this->mRestrictions = array();
2917                 $this->mRedirect = null;
2918                 $this->mLength = -1;
2919                 $this->mLatestID = false;
2920                 $this->mCounter = -1;
2921         }
2922
2923         /**
2924          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
2925          *
2926          * @param $text String containing title to capitalize
2927          * @param $ns int namespace index, defaults to NS_MAIN
2928          * @return String containing capitalized title
2929          */
2930         public static function capitalize( $text, $ns = NS_MAIN ) {
2931                 global $wgContLang;
2932
2933                 if ( MWNamespace::isCapitalized( $ns ) ) {
2934                         return $wgContLang->ucfirst( $text );
2935                 } else {
2936                         return $text;
2937                 }
2938         }
2939
2940         /**
2941          * Secure and split - main initialisation function for this object
2942          *
2943          * Assumes that mDbkeyform has been set, and is urldecoded
2944          * and uses underscores, but not otherwise munged.  This function
2945          * removes illegal characters, splits off the interwiki and
2946          * namespace prefixes, sets the other forms, and canonicalizes
2947          * everything.
2948          *
2949          * @return Bool true on success
2950          */
2951         private function secureAndSplit() {
2952                 global $wgContLang, $wgLocalInterwiki;
2953
2954                 # Initialisation
2955                 $this->mInterwiki = $this->mFragment = '';
2956                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2957
2958                 $dbkey = $this->mDbkeyform;
2959
2960                 # Strip Unicode bidi override characters.
2961                 # Sometimes they slip into cut-n-pasted page titles, where the
2962                 # override chars get included in list displays.
2963                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
2964
2965                 # Clean up whitespace
2966                 # Note: use of the /u option on preg_replace here will cause
2967                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
2968                 # conveniently disabling them.
2969                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
2970                 $dbkey = trim( $dbkey, '_' );
2971
2972                 if ( $dbkey == '' ) {
2973                         return false;
2974                 }
2975
2976                 if ( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2977                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2978                         return false;
2979                 }
2980
2981                 $this->mDbkeyform = $dbkey;
2982
2983                 # Initial colon indicates main namespace rather than specified default
2984                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
2985                 if ( ':' == $dbkey[0] ) {
2986                         $this->mNamespace = NS_MAIN;
2987                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
2988                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
2989                 }
2990
2991                 # Namespace or interwiki prefix
2992                 $firstPass = true;
2993                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
2994                 do {
2995                         $m = array();
2996                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
2997                                 $p = $m[1];
2998                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
2999                                         # Ordinary namespace
3000                                         $dbkey = $m[2];
3001                                         $this->mNamespace = $ns;
3002                                         # For Talk:X pages, check if X has a "namespace" prefix
3003                                         if ( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
3004                                                 if ( $wgContLang->getNsIndex( $x[1] ) ) {
3005                                                         # Disallow Talk:File:x type titles...
3006                                                         return false;
3007                                                 } elseif ( Interwiki::isValidInterwiki( $x[1] ) ) {
3008                                                         # Disallow Talk:Interwiki:x type titles...
3009                                                         return false;
3010                                                 }
3011                                         }
3012                                 } elseif ( Interwiki::isValidInterwiki( $p ) ) {
3013                                         if ( !$firstPass ) {
3014                                                 # Can't make a local interwiki link to an interwiki link.
3015                                                 # That's just crazy!
3016                                                 return false;
3017                                         }
3018
3019                                         # Interwiki link
3020                                         $dbkey = $m[2];
3021                                         $this->mInterwiki = $wgContLang->lc( $p );
3022
3023                                         # Redundant interwiki prefix to the local wiki
3024                                         if ( $wgLocalInterwiki !== false
3025                                                 && 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) )
3026                                         {
3027                                                 if ( $dbkey == '' ) {
3028                                                         # Can't have an empty self-link
3029                                                         return false;
3030                                                 }
3031                                                 $this->mInterwiki = '';
3032                                                 $firstPass = false;
3033                                                 # Do another namespace split...
3034                                                 continue;
3035                                         }
3036
3037                                         # If there's an initial colon after the interwiki, that also
3038                                         # resets the default namespace
3039                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
3040                                                 $this->mNamespace = NS_MAIN;
3041                                                 $dbkey = substr( $dbkey, 1 );
3042                                         }
3043                                 }
3044                                 # If there's no recognized interwiki or namespace,
3045                                 # then let the colon expression be part of the title.
3046                         }
3047                         break;
3048                 } while ( true );
3049
3050                 # We already know that some pages won't be in the database!
3051                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
3052                         $this->mArticleID = 0;
3053                 }
3054                 $fragment = strstr( $dbkey, '#' );
3055                 if ( false !== $fragment ) {
3056                         $this->setFragment( $fragment );
3057                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
3058                         # remove whitespace again: prevents "Foo_bar_#"
3059                         # becoming "Foo_bar_"
3060                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
3061                 }
3062
3063                 # Reject illegal characters.
3064                 $rxTc = self::getTitleInvalidRegex();
3065                 if ( preg_match( $rxTc, $dbkey ) ) {
3066                         return false;
3067                 }
3068
3069                 # Pages with "/./" or "/../" appearing in the URLs will often be un-
3070                 # reachable due to the way web browsers deal with 'relative' URLs.
3071                 # Also, they conflict with subpage syntax.  Forbid them explicitly.
3072                 if ( strpos( $dbkey, '.' ) !== false &&
3073                          ( $dbkey === '.' || $dbkey === '..' ||
3074                            strpos( $dbkey, './' ) === 0  ||
3075                            strpos( $dbkey, '../' ) === 0 ||
3076                            strpos( $dbkey, '/./' ) !== false ||
3077                            strpos( $dbkey, '/../' ) !== false  ||
3078                            substr( $dbkey, -2 ) == '/.' ||
3079                            substr( $dbkey, -3 ) == '/..' ) )
3080                 {
3081                         return false;
3082                 }
3083
3084                 # Magic tilde sequences? Nu-uh!
3085                 if ( strpos( $dbkey, '~~~' ) !== false ) {
3086                         return false;
3087                 }
3088
3089                 # Limit the size of titles to 255 bytes. This is typically the size of the
3090                 # underlying database field. We make an exception for special pages, which
3091                 # don't need to be stored in the database, and may edge over 255 bytes due
3092                 # to subpage syntax for long titles, e.g. [[Special:Block/Long name]]
3093                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
3094                   strlen( $dbkey ) > 512 )
3095                 {
3096                         return false;
3097                 }
3098
3099                 # Normally, all wiki links are forced to have an initial capital letter so [[foo]]
3100                 # and [[Foo]] point to the same place.  Don't force it for interwikis, since the
3101                 # other site might be case-sensitive.
3102                 $this->mUserCaseDBKey = $dbkey;
3103                 if ( $this->mInterwiki == '' ) {
3104                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
3105                 }
3106
3107                 # Can't make a link to a namespace alone... "empty" local links can only be
3108                 # self-links with a fragment identifier.
3109                 if ( $dbkey == '' && $this->mInterwiki == '' && $this->mNamespace != NS_MAIN ) {
3110                         return false;
3111                 }
3112
3113                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
3114                 // IP names are not allowed for accounts, and can only be referring to
3115                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
3116                 // there are numerous ways to present the same IP. Having sp:contribs scan
3117                 // them all is silly and having some show the edits and others not is
3118                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
3119                 $dbkey = ( $this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK )
3120                         ? IP::sanitizeIP( $dbkey )
3121                         : $dbkey;
3122
3123                 // Any remaining initial :s are illegal.
3124                 if ( $dbkey !== '' && ':' == $dbkey[0] ) {
3125                         return false;
3126                 }
3127
3128                 # Fill fields
3129                 $this->mDbkeyform = $dbkey;
3130                 $this->mUrlform = wfUrlencode( $dbkey );
3131
3132                 $this->mTextform = str_replace( '_', ' ', $dbkey );
3133
3134                 return true;
3135         }
3136
3137         /**
3138          * Get an array of Title objects linking to this Title
3139          * Also stores the IDs in the link cache.
3140          *
3141          * WARNING: do not use this function on arbitrary user-supplied titles!
3142          * On heavily-used templates it will max out the memory.
3143          *
3144          * @param $options Array: may be FOR UPDATE
3145          * @param $table String: table name
3146          * @param $prefix String: fields prefix
3147          * @return Array of Title objects linking here
3148          */
3149         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3150                 $linkCache = LinkCache::singleton();
3151
3152                 if ( count( $options ) > 0 ) {
3153                         $db = wfGetDB( DB_MASTER );
3154                 } else {
3155                         $db = wfGetDB( DB_SLAVE );
3156                 }
3157
3158                 $res = $db->select(
3159                         array( 'page', $table ),
3160                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ),
3161                         array(
3162                                 "{$prefix}_from=page_id",
3163                                 "{$prefix}_namespace" => $this->getNamespace(),
3164                                 "{$prefix}_title"     => $this->getDBkey() ),
3165                         __METHOD__,
3166                         $options
3167                 );
3168
3169                 $retVal = array();
3170                 if ( $db->numRows( $res ) ) {
3171                         foreach ( $res as $row ) {
3172                                 $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title );
3173                                 if ( $titleObj ) {
3174                                         $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3175                                         $retVal[] = $titleObj;
3176                                 }
3177                         }
3178                 }
3179                 return $retVal;
3180         }
3181
3182         /**
3183          * Get an array of Title objects using this Title as a template
3184          * Also stores the IDs in the link cache.
3185          *
3186          * WARNING: do not use this function on arbitrary user-supplied titles!
3187          * On heavily-used templates it will max out the memory.
3188          *
3189          * @param $options Array: may be FOR UPDATE
3190          * @return Array of Title the Title objects linking here
3191          */
3192         public function getTemplateLinksTo( $options = array() ) {
3193                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
3194         }
3195
3196         /**
3197          * Get an array of Title objects referring to non-existent articles linked from this page
3198          *
3199          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
3200          * @return Array of Title the Title objects
3201          */
3202         public function getBrokenLinksFrom() {
3203                 if ( $this->getArticleId() == 0 ) {
3204                         # All links from article ID 0 are false positives
3205                         return array();
3206                 }
3207
3208                 $dbr = wfGetDB( DB_SLAVE );
3209                 $res = $dbr->select(
3210                         array( 'page', 'pagelinks' ),
3211                         array( 'pl_namespace', 'pl_title' ),
3212                         array(
3213                                 'pl_from' => $this->getArticleId(),
3214                                 'page_namespace IS NULL'
3215                         ),
3216                         __METHOD__, array(),
3217                         array(
3218                                 'page' => array(
3219                                         'LEFT JOIN',
3220                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
3221                                 )
3222                         )
3223                 );
3224
3225                 $retVal = array();
3226                 foreach ( $res as $row ) {
3227                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
3228                 }
3229                 return $retVal;
3230         }
3231
3232
3233         /**
3234          * Get a list of URLs to purge from the Squid cache when this
3235          * page changes
3236          *
3237          * @return Array of String the URLs
3238          */
3239         public function getSquidURLs() {
3240                 global $wgContLang;
3241
3242                 $urls = array(
3243                         $this->getInternalURL(),
3244                         $this->getInternalURL( 'action=history' )
3245                 );
3246
3247                 // purge variant urls as well
3248                 if ( $wgContLang->hasVariants() ) {
3249                         $variants = $wgContLang->getVariants();
3250                         foreach ( $variants as $vCode ) {
3251                                 $urls[] = $this->getInternalURL( '', $vCode );
3252                         }
3253                 }
3254
3255                 return $urls;
3256         }
3257
3258         /**
3259          * Purge all applicable Squid URLs
3260          */
3261         public function purgeSquid() {
3262                 global $wgUseSquid;
3263                 if ( $wgUseSquid ) {
3264                         $urls = $this->getSquidURLs();
3265                         $u = new SquidUpdate( $urls );
3266                         $u->doUpdate();
3267                 }
3268         }
3269
3270         /**
3271          * Move this page without authentication
3272          *
3273          * @param $nt Title the new page Title
3274          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3275          */
3276         public function moveNoAuth( &$nt ) {
3277                 return $this->moveTo( $nt, false );
3278         }
3279
3280         /**
3281          * Check whether a given move operation would be valid.
3282          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
3283          *
3284          * @param $nt Title the new title
3285          * @param $auth Bool indicates whether $wgUser's permissions
3286          *  should be checked
3287          * @param $reason String is the log summary of the move, used for spam checking
3288          * @return Mixed True on success, getUserPermissionsErrors()-like array on failure
3289          */
3290         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
3291                 global $wgUser;
3292
3293                 $errors = array();
3294                 if ( !$nt ) {
3295                         // Normally we'd add this to $errors, but we'll get
3296                         // lots of syntax errors if $nt is not an object
3297                         return array( array( 'badtitletext' ) );
3298                 }
3299                 if ( $this->equals( $nt ) ) {
3300                         $errors[] = array( 'selfmove' );
3301                 }
3302                 if ( !$this->isMovable() ) {
3303                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
3304                 }
3305                 if ( $nt->getInterwiki() != '' ) {
3306                         $errors[] = array( 'immobile-target-namespace-iw' );
3307                 }
3308                 if ( !$nt->isMovable() ) {
3309                         $errors[] = array( 'immobile-target-namespace', $nt->getNsText() );
3310                 }
3311
3312                 $oldid = $this->getArticleID();
3313                 $newid = $nt->getArticleID();
3314
3315                 if ( strlen( $nt->getDBkey() ) < 1 ) {
3316                         $errors[] = array( 'articleexists' );
3317                 }
3318                 if ( ( $this->getDBkey() == '' ) ||
3319                          ( !$oldid ) ||
3320                          ( $nt->getDBkey() == '' ) ) {
3321                         $errors[] = array( 'badarticleerror' );
3322                 }
3323
3324                 // Image-specific checks
3325                 if ( $this->getNamespace() == NS_FILE ) {
3326                         $errors = array_merge( $errors, $this->validateFileMoveOperation( $nt ) );
3327                 }
3328
3329                 if ( $nt->getNamespace() == NS_FILE && $this->getNamespace() != NS_FILE ) {
3330                         $errors[] = array( 'nonfile-cannot-move-to-file' );
3331                 }
3332
3333                 if ( $auth ) {
3334                         $errors = wfMergeErrorArrays( $errors,
3335                                 $this->getUserPermissionsErrors( 'move', $wgUser ),
3336                                 $this->getUserPermissionsErrors( 'edit', $wgUser ),
3337                                 $nt->getUserPermissionsErrors( 'move-target', $wgUser ),
3338                                 $nt->getUserPermissionsErrors( 'edit', $wgUser ) );
3339                 }
3340
3341                 $match = EditPage::matchSummarySpamRegex( $reason );
3342                 if ( $match !== false ) {
3343                         // This is kind of lame, won't display nice
3344                         $errors[] = array( 'spamprotectiontext' );
3345                 }
3346
3347                 $err = null;
3348                 if ( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
3349                         $errors[] = array( 'hookaborted', $err );
3350                 }
3351
3352                 # The move is allowed only if (1) the target doesn't exist, or
3353                 # (2) the target is a redirect to the source, and has no history
3354                 # (so we can undo bad moves right after they're done).
3355
3356                 if ( 0 != $newid ) { # Target exists; check for validity
3357                         if ( !$this->isValidMoveTarget( $nt ) ) {
3358                                 $errors[] = array( 'articleexists' );
3359                         }
3360                 } else {
3361                         $tp = $nt->getTitleProtection();
3362                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
3363                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
3364                                 $errors[] = array( 'cantmove-titleprotected' );
3365                         }
3366                 }
3367                 if ( empty( $errors ) ) {
3368                         return true;
3369                 }
3370                 return $errors;
3371         }
3372
3373         /**
3374          * Check if the requested move target is a valid file move target
3375          * @param Title $nt Target title
3376          * @return array List of errors
3377          */
3378         protected function validateFileMoveOperation( $nt ) {
3379                 global $wgUser;
3380
3381                 $errors = array();
3382
3383                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is not allowed until below
3384
3385                 $file = wfLocalFile( $this );
3386                 if ( $file->exists() ) {
3387                         if ( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
3388                                 $errors[] = array( 'imageinvalidfilename' );
3389                         }
3390                         if ( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
3391                                 $errors[] = array( 'imagetypemismatch' );
3392                         }
3393                 }
3394
3395                 if ( $nt->getNamespace() != NS_FILE ) {
3396                         $errors[] = array( 'imagenocrossnamespace' );
3397                         // From here we want to do checks on a file object, so if we can't
3398                         // create one, we must return.
3399                         return $errors;
3400                 }
3401
3402                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is allowed below here
3403
3404                 $destFile = wfLocalFile( $nt );
3405                 if ( !$wgUser->isAllowed( 'reupload-shared' ) && !$destFile->exists() && wfFindFile( $nt ) ) {
3406                         $errors[] = array( 'file-exists-sharedrepo' );
3407                 }
3408
3409                 return $errors;
3410         }
3411
3412         /**
3413          * Move a title to a new location
3414          *
3415          * @param $nt Title the new title
3416          * @param $auth Bool indicates whether $wgUser's permissions
3417          *  should be checked
3418          * @param $reason String the reason for the move
3419          * @param $createRedirect Bool Whether to create a redirect from the old title to the new title.
3420          *  Ignored if the user doesn't have the suppressredirect right.
3421          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3422          */
3423         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
3424                 global $wgUser;
3425                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
3426                 if ( is_array( $err ) ) {
3427                         // Auto-block user's IP if the account was "hard" blocked
3428                         $wgUser->spreadAnyEditBlock();
3429                         return $err;
3430                 }
3431
3432                 // If it is a file, move it first.
3433                 // It is done before all other moving stuff is done because it's hard to revert.
3434                 $dbw = wfGetDB( DB_MASTER );
3435                 if ( $this->getNamespace() == NS_FILE ) {
3436                         $file = wfLocalFile( $this );
3437                         if ( $file->exists() ) {
3438                                 $status = $file->move( $nt );
3439                                 if ( !$status->isOk() ) {
3440                                         return $status->getErrorsArray();
3441                                 }
3442                         }
3443                 }
3444                 // Clear RepoGroup process cache
3445                 RepoGroup::singleton()->clearCache( $this );
3446                 RepoGroup::singleton()->clearCache( $nt ); # clear false negative cache
3447
3448                 $dbw->begin(); # If $file was a LocalFile, its transaction would have closed our own.
3449                 $pageid = $this->getArticleID( self::GAID_FOR_UPDATE );
3450                 $protected = $this->isProtected();
3451                 $pageCountChange = ( $createRedirect ? 1 : 0 ) - ( $nt->exists() ? 1 : 0 );
3452
3453                 // Do the actual move
3454                 $err = $this->moveToInternal( $nt, $reason, $createRedirect );
3455                 if ( is_array( $err ) ) {
3456                         # @todo FIXME: What about the File we have already moved?
3457                         $dbw->rollback();
3458                         return $err;
3459                 }
3460
3461                 $redirid = $this->getArticleID();
3462
3463                 // Refresh the sortkey for this row.  Be careful to avoid resetting
3464                 // cl_timestamp, which may disturb time-based lists on some sites.
3465                 $prefixes = $dbw->select(
3466                         'categorylinks',
3467                         array( 'cl_sortkey_prefix', 'cl_to' ),
3468                         array( 'cl_from' => $pageid ),
3469                         __METHOD__
3470                 );
3471                 foreach ( $prefixes as $prefixRow ) {
3472                         $prefix = $prefixRow->cl_sortkey_prefix;
3473                         $catTo = $prefixRow->cl_to;
3474                         $dbw->update( 'categorylinks',
3475                                 array(
3476                                         'cl_sortkey' => Collation::singleton()->getSortKey(
3477                                                 $nt->getCategorySortkey( $prefix ) ),
3478                                         'cl_timestamp=cl_timestamp' ),
3479                                 array(
3480                                         'cl_from' => $pageid,
3481                                         'cl_to' => $catTo ),
3482                                 __METHOD__
3483                         );
3484                 }
3485
3486                 if ( $protected ) {
3487                         # Protect the redirect title as the title used to be...
3488                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
3489                                 array(
3490                                         'pr_page'    => $redirid,
3491                                         'pr_type'    => 'pr_type',
3492                                         'pr_level'   => 'pr_level',
3493                                         'pr_cascade' => 'pr_cascade',
3494                                         'pr_user'    => 'pr_user',
3495                                         'pr_expiry'  => 'pr_expiry'
3496                                 ),
3497                                 array( 'pr_page' => $pageid ),
3498                                 __METHOD__,
3499                                 array( 'IGNORE' )
3500                         );
3501                         # Update the protection log
3502                         $log = new LogPage( 'protect' );
3503                         $comment = wfMsgForContent( 'prot_1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
3504                         if ( $reason ) {
3505                                 $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3506                         }
3507                         // @todo FIXME: $params?
3508                         $log->addEntry( 'move_prot', $nt, $comment, array( $this->getPrefixedText() ) );
3509                 }
3510
3511                 # Update watchlists
3512                 $oldnamespace = $this->getNamespace() & ~1;
3513                 $newnamespace = $nt->getNamespace() & ~1;
3514                 $oldtitle = $this->getDBkey();
3515                 $newtitle = $nt->getDBkey();
3516
3517                 if ( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
3518                         WatchedItem::duplicateEntries( $this, $nt );
3519                 }
3520
3521                 # Update search engine
3522                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
3523                 $u->doUpdate();
3524                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
3525                 $u->doUpdate();
3526
3527                 $dbw->commit();
3528
3529                 # Update site_stats
3530                 if ( $this->isContentPage() && !$nt->isContentPage() ) {
3531                         # No longer a content page
3532                         # Not viewed, edited, removing
3533                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange );
3534                 } elseif ( !$this->isContentPage() && $nt->isContentPage() ) {
3535                         # Now a content page
3536                         # Not viewed, edited, adding
3537                         $u = new SiteStatsUpdate( 0, 1, + 1, $pageCountChange );
3538                 } elseif ( $pageCountChange ) {
3539                         # Redirect added
3540                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
3541                 } else {
3542                         # Nothing special
3543                         $u = false;
3544                 }
3545                 if ( $u ) {
3546                         $u->doUpdate();
3547                 }
3548
3549                 # Update message cache for interface messages
3550                 if ( $this->getNamespace() == NS_MEDIAWIKI ) {
3551                         # @bug 17860: old article can be deleted, if this the case,
3552                         # delete it from message cache
3553                         if ( $this->getArticleID() === 0 ) {
3554                                 MessageCache::singleton()->replace( $this->getDBkey(), false );
3555                         } else {
3556                                 $rev = Revision::newFromTitle( $this );
3557                                 MessageCache::singleton()->replace( $this->getDBkey(), $rev->getText() );
3558                         }
3559                 }
3560                 if ( $nt->getNamespace() == NS_MEDIAWIKI ) {
3561                         $rev = Revision::newFromTitle( $nt );
3562                         MessageCache::singleton()->replace( $nt->getDBkey(), $rev->getText() );
3563                 }
3564
3565                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3566                 return true;
3567         }
3568
3569         /**
3570          * Move page to a title which is either a redirect to the
3571          * source page or nonexistent
3572          *
3573          * @param $nt Title the page to move to, which should be a redirect or nonexistent
3574          * @param $reason String The reason for the move
3575          * @param $createRedirect Bool Whether to leave a redirect at the old title.  Ignored
3576          *   if the user doesn't have the suppressredirect right
3577          */
3578         private function moveToInternal( &$nt, $reason = '', $createRedirect = true ) {
3579                 global $wgUser, $wgContLang;
3580
3581                 if ( $nt->exists() ) {
3582                         $moveOverRedirect = true;
3583                         $logType = 'move_redir';
3584                 } else {
3585                         $moveOverRedirect = false;
3586                         $logType = 'move';
3587                 }
3588
3589                 $redirectSuppressed = !$createRedirect && $wgUser->isAllowed( 'suppressredirect' );
3590
3591                 $logEntry = new ManualLogEntry( 'move', $logType );
3592                 $logEntry->setPerformer( $wgUser );
3593                 $logEntry->setTarget( $this );
3594                 $logEntry->setComment( $reason );
3595                 $logEntry->setParameters( array(
3596                         '4::target' => $nt->getPrefixedText(),
3597                         '5::noredir' => $redirectSuppressed ? '1': '0',
3598                 ) );
3599
3600                 $formatter = LogFormatter::newFromEntry( $logEntry );
3601                 $formatter->setContext( RequestContext::newExtraneousContext( $this ) );
3602                 $comment = $formatter->getPlainActionText();
3603                 if ( $reason ) {
3604                         $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3605                 }
3606                 # Truncate for whole multibyte characters.
3607                 $comment = $wgContLang->truncate( $comment, 255 );
3608
3609                 $oldid = $this->getArticleID();
3610                 $latest = $this->getLatestRevID();
3611
3612                 $dbw = wfGetDB( DB_MASTER );
3613
3614                 if ( $moveOverRedirect ) {
3615                         $rcts = $dbw->timestamp( $nt->getEarliestRevTime() );
3616
3617                         $newid = $nt->getArticleID();
3618                         $newns = $nt->getNamespace();
3619                         $newdbk = $nt->getDBkey();
3620
3621                         # Delete the old redirect. We don't save it to history since
3622                         # by definition if we've got here it's rather uninteresting.
3623                         # We have to remove it so that the next step doesn't trigger
3624                         # a conflict on the unique namespace+title index...
3625                         $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3626                         if ( !$dbw->cascadingDeletes() ) {
3627                                 $dbw->delete( 'revision', array( 'rev_page' => $newid ), __METHOD__ );
3628
3629                                 $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
3630                                 $dbw->delete( 'imagelinks', array( 'il_from' => $newid ), __METHOD__ );
3631                                 $dbw->delete( 'categorylinks', array( 'cl_from' => $newid ), __METHOD__ );
3632                                 $dbw->delete( 'templatelinks', array( 'tl_from' => $newid ), __METHOD__ );
3633                                 $dbw->delete( 'externallinks', array( 'el_from' => $newid ), __METHOD__ );
3634                                 $dbw->delete( 'langlinks', array( 'll_from' => $newid ), __METHOD__ );
3635                                 $dbw->delete( 'iwlinks', array( 'iwl_from' => $newid ), __METHOD__ );
3636                                 $dbw->delete( 'redirect', array( 'rd_from' => $newid ), __METHOD__ );
3637                                 $dbw->delete( 'page_props', array( 'pp_page' => $newid ), __METHOD__ );
3638                         }
3639                         // If the target page was recently created, it may have an entry in recentchanges still
3640                         $dbw->delete( 'recentchanges',
3641                                 array( 'rc_timestamp' => $rcts, 'rc_namespace' => $newns, 'rc_title' => $newdbk, 'rc_new' => 1 ),
3642                                 __METHOD__
3643                         );
3644                 }
3645
3646                 # Save a null revision in the page's history notifying of the move
3647                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3648                 if ( !is_object( $nullRevision ) ) {
3649                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3650                 }
3651                 $nullRevId = $nullRevision->insertOn( $dbw );
3652
3653                 $now = wfTimestampNow();
3654                 # Change the name of the target page:
3655                 $dbw->update( 'page',
3656                         /* SET */ array(
3657                                 'page_touched'   => $dbw->timestamp( $now ),
3658                                 'page_namespace' => $nt->getNamespace(),
3659                                 'page_title'     => $nt->getDBkey(),
3660                                 'page_latest'    => $nullRevId,
3661                         ),
3662                         /* WHERE */ array( 'page_id' => $oldid ),
3663                         __METHOD__
3664                 );
3665                 $nt->resetArticleID( $oldid );
3666
3667                 $article = WikiPage::factory( $nt );
3668                 wfRunHooks( 'NewRevisionFromEditComplete',
3669                         array( $article, $nullRevision, $latest, $wgUser ) );
3670                 $article->setCachedLastEditTime( $now );
3671
3672                 # Recreate the redirect, this time in the other direction.
3673                 if ( $createRedirect || !$wgUser->isAllowed( 'suppressredirect' ) ) {
3674                         $mwRedir = MagicWord::get( 'redirect' );
3675                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3676                         $redirectArticle = WikiPage::factory( $this );
3677                         $newid = $redirectArticle->insertOn( $dbw );
3678                         if ( $newid ) { // sanity
3679                                 $redirectRevision = new Revision( array(
3680                                         'page'    => $newid,
3681                                         'comment' => $comment,
3682                                         'text'    => $redirectText ) );
3683                                 $redirectRevision->insertOn( $dbw );
3684                                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3685
3686                                 wfRunHooks( 'NewRevisionFromEditComplete',
3687                                         array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3688
3689                                 # Now, we record the link from the redirect to the new title.
3690                                 # It should have no other outgoing links...
3691                                 $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
3692                                 $dbw->insert( 'pagelinks',
3693                                         array(
3694                                                 'pl_from'      => $newid,
3695                                                 'pl_namespace' => $nt->getNamespace(),
3696                                                 'pl_title'     => $nt->getDBkey() ),
3697                                         __METHOD__ );
3698                         }
3699                 } else {
3700                         $this->resetArticleID( 0 );
3701                 }
3702
3703                 # Log the move
3704                 $logid = $logEntry->insert();
3705                 $logEntry->publish( $logid );
3706
3707                 # Purge caches for old and new titles
3708                 if ( $moveOverRedirect ) {
3709                         # A simple purge is enough when moving over a redirect
3710                         $nt->purgeSquid();
3711                 } else {
3712                         # Purge caches as per article creation, including any pages that link to this title
3713                         Article::onArticleCreate( $nt );
3714                 }
3715                 $this->purgeSquid();
3716         }
3717
3718         /**
3719          * Move this page's subpages to be subpages of $nt
3720          *
3721          * @param $nt Title Move target
3722          * @param $auth bool Whether $wgUser's permissions should be checked
3723          * @param $reason string The reason for the move
3724          * @param $createRedirect bool Whether to create redirects from the old subpages to
3725          *     the new ones Ignored if the user doesn't have the 'suppressredirect' right
3726          * @return mixed array with old page titles as keys, and strings (new page titles) or
3727          *     arrays (errors) as values, or an error array with numeric indices if no pages
3728          *     were moved
3729          */
3730         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3731                 global $wgMaximumMovedPages;
3732                 // Check permissions
3733                 if ( !$this->userCan( 'move-subpages' ) ) {
3734                         return array( 'cant-move-subpages' );
3735                 }
3736                 // Do the source and target namespaces support subpages?
3737                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
3738                         return array( 'namespace-nosubpages',
3739                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3740                 }
3741                 if ( !MWNamespace::hasSubpages( $nt->getNamespace() ) ) {
3742                         return array( 'namespace-nosubpages',
3743                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3744                 }
3745
3746                 $subpages = $this->getSubpages( $wgMaximumMovedPages + 1 );
3747                 $retval = array();
3748                 $count = 0;
3749                 foreach ( $subpages as $oldSubpage ) {
3750                         $count++;
3751                         if ( $count > $wgMaximumMovedPages ) {
3752                                 $retval[$oldSubpage->getPrefixedTitle()] =
3753                                                 array( 'movepage-max-pages',
3754                                                         $wgMaximumMovedPages );
3755                                 break;
3756                         }
3757
3758                         // We don't know whether this function was called before
3759                         // or after moving the root page, so check both
3760                         // $this and $nt
3761                         if ( $oldSubpage->getArticleId() == $this->getArticleId() ||
3762                                         $oldSubpage->getArticleID() == $nt->getArticleId() )
3763                         {
3764                                 // When moving a page to a subpage of itself,
3765                                 // don't move it twice
3766                                 continue;
3767                         }
3768                         $newPageName = preg_replace(
3769                                         '#^' . preg_quote( $this->getDBkey(), '#' ) . '#',
3770                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3771                                         $oldSubpage->getDBkey() );
3772                         if ( $oldSubpage->isTalkPage() ) {
3773                                 $newNs = $nt->getTalkPage()->getNamespace();
3774                         } else {
3775                                 $newNs = $nt->getSubjectPage()->getNamespace();
3776                         }
3777                         # Bug 14385: we need makeTitleSafe because the new page names may
3778                         # be longer than 255 characters.
3779                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3780
3781                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3782                         if ( $success === true ) {
3783                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3784                         } else {
3785                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3786                         }
3787                 }
3788                 return $retval;
3789         }
3790
3791         /**
3792          * Checks if this page is just a one-rev redirect.
3793          * Adds lock, so don't use just for light purposes.
3794          *
3795          * @return Bool
3796          */
3797         public function isSingleRevRedirect() {
3798                 $dbw = wfGetDB( DB_MASTER );
3799                 # Is it a redirect?
3800                 $row = $dbw->selectRow( 'page',
3801                         array( 'page_is_redirect', 'page_latest', 'page_id' ),
3802                         $this->pageCond(),
3803                         __METHOD__,
3804                         array( 'FOR UPDATE' )
3805                 );
3806                 # Cache some fields we may want
3807                 $this->mArticleID = $row ? intval( $row->page_id ) : 0;
3808                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3809                 $this->mLatestID = $row ? intval( $row->page_latest ) : false;
3810                 if ( !$this->mRedirect ) {
3811                         return false;
3812                 }
3813                 # Does the article have a history?
3814                 $row = $dbw->selectField( array( 'page', 'revision' ),
3815                         'rev_id',
3816                         array( 'page_namespace' => $this->getNamespace(),
3817                                 'page_title' => $this->getDBkey(),
3818                                 'page_id=rev_page',
3819                                 'page_latest != rev_id'
3820                         ),
3821                         __METHOD__,
3822                         array( 'FOR UPDATE' )
3823                 );
3824                 # Return true if there was no history
3825                 return ( $row === false );
3826         }
3827
3828         /**
3829          * Checks if $this can be moved to a given Title
3830          * - Selects for update, so don't call it unless you mean business
3831          *
3832          * @param $nt Title the new title to check
3833          * @return Bool
3834          */
3835         public function isValidMoveTarget( $nt ) {
3836                 # Is it an existing file?
3837                 if ( $nt->getNamespace() == NS_FILE ) {
3838                         $file = wfLocalFile( $nt );
3839                         if ( $file->exists() ) {
3840                                 wfDebug( __METHOD__ . ": file exists\n" );
3841                                 return false;
3842                         }
3843                 }
3844                 # Is it a redirect with no history?
3845                 if ( !$nt->isSingleRevRedirect() ) {
3846                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3847                         return false;
3848                 }
3849                 # Get the article text
3850                 $rev = Revision::newFromTitle( $nt );
3851                 if( !is_object( $rev ) ){
3852                         return false;
3853                 }
3854                 $text = $rev->getText();
3855                 # Does the redirect point to the source?
3856                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3857                 $m = array();
3858                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
3859                         $redirTitle = Title::newFromText( $m[1] );
3860                         if ( !is_object( $redirTitle ) ||
3861                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3862                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
3863                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3864                                 return false;
3865                         }
3866                 } else {
3867                         # Fail safe
3868                         wfDebug( __METHOD__ . ": failsafe\n" );
3869                         return false;
3870                 }
3871                 return true;
3872         }
3873
3874         /**
3875          * Get categories to which this Title belongs and return an array of
3876          * categories' names.
3877          *
3878          * @return Array of parents in the form:
3879          *        $parent => $currentarticle
3880          */
3881         public function getParentCategories() {
3882                 global $wgContLang;
3883
3884                 $data = array();
3885
3886                 $titleKey = $this->getArticleId();
3887
3888                 if ( $titleKey === 0 ) {
3889                         return $data;
3890                 }
3891
3892                 $dbr = wfGetDB( DB_SLAVE );
3893
3894                 $res = $dbr->select( 'categorylinks', '*',
3895                         array(
3896                                 'cl_from' => $titleKey,
3897                         ),
3898                         __METHOD__,
3899                         array()
3900                 );
3901
3902                 if ( $dbr->numRows( $res ) > 0 ) {
3903                         foreach ( $res as $row ) {
3904                                 // $data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
3905                                 $data[$wgContLang->getNSText( NS_CATEGORY ) . ':' . $row->cl_to] = $this->getFullText();
3906                         }
3907                 }
3908                 return $data;
3909         }
3910
3911         /**
3912          * Get a tree of parent categories
3913          *
3914          * @param $children Array with the children in the keys, to check for circular refs
3915          * @return Array Tree of parent categories
3916          */
3917         public function getParentCategoryTree( $children = array() ) {
3918                 $stack = array();
3919                 $parents = $this->getParentCategories();
3920
3921                 if ( $parents ) {
3922                         foreach ( $parents as $parent => $current ) {
3923                                 if ( array_key_exists( $parent, $children ) ) {
3924                                         # Circular reference
3925                                         $stack[$parent] = array();
3926                                 } else {
3927                                         $nt = Title::newFromText( $parent );
3928                                         if ( $nt ) {
3929                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array( $parent => 1 ) );
3930                                         }
3931                                 }
3932                         }
3933                 }
3934
3935                 return $stack;
3936         }
3937
3938         /**
3939          * Get an associative array for selecting this title from
3940          * the "page" table
3941          *
3942          * @return Array suitable for the $where parameter of DB::select()
3943          */
3944         public function pageCond() {
3945                 if ( $this->mArticleID > 0 ) {
3946                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
3947                         return array( 'page_id' => $this->mArticleID );
3948                 } else {
3949                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
3950                 }
3951         }
3952
3953         /**
3954          * Get the revision ID of the previous revision
3955          *
3956          * @param $revId Int Revision ID. Get the revision that was before this one.
3957          * @param $flags Int Title::GAID_FOR_UPDATE
3958          * @return Int|Bool Old revision ID, or FALSE if none exists
3959          */
3960         public function getPreviousRevisionID( $revId, $flags = 0 ) {
3961                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3962                 return $db->selectField( 'revision', 'rev_id',
3963                         array(
3964                                 'rev_page' => $this->getArticleId( $flags ),
3965                                 'rev_id < ' . intval( $revId )
3966                         ),
3967                         __METHOD__,
3968                         array( 'ORDER BY' => 'rev_id DESC' )
3969                 );
3970         }
3971
3972         /**
3973          * Get the revision ID of the next revision
3974          *
3975          * @param $revId Int Revision ID. Get the revision that was after this one.
3976          * @param $flags Int Title::GAID_FOR_UPDATE
3977          * @return Int|Bool Next revision ID, or FALSE if none exists
3978          */
3979         public function getNextRevisionID( $revId, $flags = 0 ) {
3980                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3981                 return $db->selectField( 'revision', 'rev_id',
3982                         array(
3983                                 'rev_page' => $this->getArticleId( $flags ),
3984                                 'rev_id > ' . intval( $revId )
3985                         ),
3986                         __METHOD__,
3987                         array( 'ORDER BY' => 'rev_id' )
3988                 );
3989         }
3990
3991         /**
3992          * Get the first revision of the page
3993          *
3994          * @param $flags Int Title::GAID_FOR_UPDATE
3995          * @return Revision|Null if page doesn't exist
3996          */
3997         public function getFirstRevision( $flags = 0 ) {
3998                 $pageId = $this->getArticleId( $flags );
3999                 if ( $pageId ) {
4000                         $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4001                         $row = $db->selectRow( 'revision', '*',
4002                                 array( 'rev_page' => $pageId ),
4003                                 __METHOD__,
4004                                 array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
4005                         );
4006                         if ( $row ) {
4007                                 return new Revision( $row );
4008                         }
4009                 }
4010                 return null;
4011         }
4012
4013         /**
4014          * Get the oldest revision timestamp of this page
4015          *
4016          * @param $flags Int Title::GAID_FOR_UPDATE
4017          * @return String: MW timestamp
4018          */
4019         public function getEarliestRevTime( $flags = 0 ) {
4020                 $rev = $this->getFirstRevision( $flags );
4021                 return $rev ? $rev->getTimestamp() : null;
4022         }
4023
4024         /**
4025          * Check if this is a new page
4026          *
4027          * @return bool
4028          */
4029         public function isNewPage() {
4030                 $dbr = wfGetDB( DB_SLAVE );
4031                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
4032         }
4033
4034         /**
4035          * Get the number of revisions between the given revision.
4036          * Used for diffs and other things that really need it.
4037          *
4038          * @param $old int|Revision Old revision or rev ID (first before range)
4039          * @param $new int|Revision New revision or rev ID (first after range)
4040          * @return Int Number of revisions between these revisions.
4041          */
4042         public function countRevisionsBetween( $old, $new ) {
4043                 if ( !( $old instanceof Revision ) ) {
4044                         $old = Revision::newFromTitle( $this, (int)$old );
4045                 }
4046                 if ( !( $new instanceof Revision ) ) {
4047                         $new = Revision::newFromTitle( $this, (int)$new );
4048                 }
4049                 if ( !$old || !$new ) {
4050                         return 0; // nothing to compare
4051                 }
4052                 $dbr = wfGetDB( DB_SLAVE );
4053                 return (int)$dbr->selectField( 'revision', 'count(*)',
4054                         array(
4055                                 'rev_page' => $this->getArticleId(),
4056                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4057                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4058                         ),
4059                         __METHOD__
4060                 );
4061         }
4062
4063         /**
4064          * Get the number of authors between the given revision IDs.
4065          * Used for diffs and other things that really need it.
4066          *
4067          * @param $old int|Revision Old revision or rev ID (first before range)
4068          * @param $new int|Revision New revision or rev ID (first after range)
4069          * @param $limit Int Maximum number of authors
4070          * @return Int Number of revision authors between these revisions.
4071          */
4072         public function countAuthorsBetween( $old, $new, $limit ) {
4073                 if ( !( $old instanceof Revision ) ) {
4074                         $old = Revision::newFromTitle( $this, (int)$old );
4075                 }
4076                 if ( !( $new instanceof Revision ) ) {
4077                         $new = Revision::newFromTitle( $this, (int)$new );
4078                 }
4079                 if ( !$old || !$new ) {
4080                         return 0; // nothing to compare
4081                 }
4082                 $dbr = wfGetDB( DB_SLAVE );
4083                 $res = $dbr->select( 'revision', 'DISTINCT rev_user_text',
4084                         array(
4085                                 'rev_page' => $this->getArticleID(),
4086                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4087                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4088                         ), __METHOD__,
4089                         array( 'LIMIT' => $limit + 1 ) // add one so caller knows it was truncated
4090                 );
4091                 return (int)$dbr->numRows( $res );
4092         }
4093
4094         /**
4095          * Compare with another title.
4096          *
4097          * @param $title Title
4098          * @return Bool
4099          */
4100         public function equals( Title $title ) {
4101                 // Note: === is necessary for proper matching of number-like titles.
4102                 return $this->getInterwiki() === $title->getInterwiki()
4103                         && $this->getNamespace() == $title->getNamespace()
4104                         && $this->getDBkey() === $title->getDBkey();
4105         }
4106
4107         /**
4108          * Check if this title is a subpage of another title
4109          *
4110          * @param $title Title
4111          * @return Bool
4112          */
4113         public function isSubpageOf( Title $title ) {
4114                 return $this->getInterwiki() === $title->getInterwiki()
4115                         && $this->getNamespace() == $title->getNamespace()
4116                         && strpos( $this->getDBkey(), $title->getDBkey() . '/' ) === 0;
4117         }
4118
4119         /**
4120          * Check if page exists.  For historical reasons, this function simply
4121          * checks for the existence of the title in the page table, and will
4122          * thus return false for interwiki links, special pages and the like.
4123          * If you want to know if a title can be meaningfully viewed, you should
4124          * probably call the isKnown() method instead.
4125          *
4126          * @return Bool
4127          */
4128         public function exists() {
4129                 return $this->getArticleId() != 0;
4130         }
4131
4132         /**
4133          * Should links to this title be shown as potentially viewable (i.e. as
4134          * "bluelinks"), even if there's no record by this title in the page
4135          * table?
4136          *
4137          * This function is semi-deprecated for public use, as well as somewhat
4138          * misleadingly named.  You probably just want to call isKnown(), which
4139          * calls this function internally.
4140          *
4141          * (ISSUE: Most of these checks are cheap, but the file existence check
4142          * can potentially be quite expensive.  Including it here fixes a lot of
4143          * existing code, but we might want to add an optional parameter to skip
4144          * it and any other expensive checks.)
4145          *
4146          * @return Bool
4147          */
4148         public function isAlwaysKnown() {
4149                 if ( $this->mInterwiki != '' ) {
4150                         return true;  // any interwiki link might be viewable, for all we know
4151                 }
4152                 switch( $this->mNamespace ) {
4153                         case NS_MEDIA:
4154                         case NS_FILE:
4155                                 // file exists, possibly in a foreign repo
4156                                 return (bool)wfFindFile( $this );
4157                         case NS_SPECIAL:
4158                                 // valid special page
4159                                 return SpecialPageFactory::exists( $this->getDBkey() );
4160                         case NS_MAIN:
4161                                 // selflink, possibly with fragment
4162                                 return $this->mDbkeyform == '';
4163                         case NS_MEDIAWIKI:
4164                                 // known system message
4165                                 return $this->hasSourceText() !== false;
4166                         default:
4167                                 return false;
4168                 }
4169         }
4170
4171         /**
4172          * Does this title refer to a page that can (or might) be meaningfully
4173          * viewed?  In particular, this function may be used to determine if
4174          * links to the title should be rendered as "bluelinks" (as opposed to
4175          * "redlinks" to non-existent pages).
4176          *
4177          * @return Bool
4178          */
4179         public function isKnown() {
4180                 return $this->isAlwaysKnown() || $this->exists();
4181         }
4182
4183         /**
4184          * Does this page have source text?
4185          *
4186          * @return Boolean
4187          */
4188         public function hasSourceText() {
4189                 if ( $this->exists() ) {
4190                         return true;
4191                 }
4192
4193                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
4194                         // If the page doesn't exist but is a known system message, default
4195                         // message content will be displayed, same for language subpages-
4196                         // Use always content language to avoid loading hundreds of languages
4197                         // to get the link color.
4198                         global $wgContLang;
4199                         list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4200                         $message = wfMessage( $name )->inLanguage( $wgContLang )->useDatabase( false );
4201                         return $message->exists();
4202                 }
4203
4204                 return false;
4205         }
4206
4207         /**
4208          * Get the default message text or false if the message doesn't exist
4209          *
4210          * @return String or false
4211          */
4212         public function getDefaultMessageText() {
4213                 global $wgContLang;
4214
4215                 if ( $this->getNamespace() != NS_MEDIAWIKI ) { // Just in case
4216                         return false;
4217                 }
4218
4219                 list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4220                 $message = wfMessage( $name )->inLanguage( $lang )->useDatabase( false );
4221
4222                 if ( $message->exists() ) {
4223                         return $message->plain();
4224                 } else {
4225                         return false;
4226                 }
4227         }
4228
4229         /**
4230          * Updates page_touched for this page; called from LinksUpdate.php
4231          *
4232          * @return Bool true if the update succeded
4233          */
4234         public function invalidateCache() {
4235                 if ( wfReadOnly() ) {
4236                         return false;
4237                 }
4238                 $dbw = wfGetDB( DB_MASTER );
4239                 $success = $dbw->update(
4240                         'page',
4241                         array( 'page_touched' => $dbw->timestamp() ),
4242                         $this->pageCond(),
4243                         __METHOD__
4244                 );
4245                 HTMLFileCache::clearFileCache( $this );
4246                 return $success;
4247         }
4248
4249         /**
4250          * Update page_touched timestamps and send squid purge messages for
4251          * pages linking to this title. May be sent to the job queue depending
4252          * on the number of links. Typically called on create and delete.
4253          */
4254         public function touchLinks() {
4255                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
4256                 $u->doUpdate();
4257
4258                 if ( $this->getNamespace() == NS_CATEGORY ) {
4259                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
4260                         $u->doUpdate();
4261                 }
4262         }
4263
4264         /**
4265          * Get the last touched timestamp
4266          *
4267          * @param $db DatabaseBase: optional db
4268          * @return String last-touched timestamp
4269          */
4270         public function getTouched( $db = null ) {
4271                 $db = isset( $db ) ? $db : wfGetDB( DB_SLAVE );
4272                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
4273                 return $touched;
4274         }
4275
4276         /**
4277          * Get the timestamp when this page was updated since the user last saw it.
4278          *
4279          * @param $user User
4280          * @return String|Null
4281          */
4282         public function getNotificationTimestamp( $user = null ) {
4283                 global $wgUser, $wgShowUpdatedMarker;
4284                 // Assume current user if none given
4285                 if ( !$user ) {
4286                         $user = $wgUser;
4287                 }
4288                 // Check cache first
4289                 $uid = $user->getId();
4290                 // avoid isset here, as it'll return false for null entries
4291                 if ( array_key_exists( $uid, $this->mNotificationTimestamp ) ) {
4292                         return $this->mNotificationTimestamp[$uid];
4293                 }
4294                 if ( !$uid || !$wgShowUpdatedMarker ) {
4295                         return $this->mNotificationTimestamp[$uid] = false;
4296                 }
4297                 // Don't cache too much!
4298                 if ( count( $this->mNotificationTimestamp ) >= self::CACHE_MAX ) {
4299                         $this->mNotificationTimestamp = array();
4300                 }
4301                 $dbr = wfGetDB( DB_SLAVE );
4302                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
4303                         'wl_notificationtimestamp',
4304                         array( 'wl_namespace' => $this->getNamespace(),
4305                                 'wl_title' => $this->getDBkey(),
4306                                 'wl_user' => $user->getId()
4307                         ),
4308                         __METHOD__
4309                 );
4310                 return $this->mNotificationTimestamp[$uid];
4311         }
4312
4313         /**
4314          * Generate strings used for xml 'id' names in monobook tabs
4315          *
4316          * @param $prepend string defaults to 'nstab-'
4317          * @return String XML 'id' name
4318          */
4319         public function getNamespaceKey( $prepend = 'nstab-' ) {
4320                 global $wgContLang;
4321                 // Gets the subject namespace if this title
4322                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
4323                 // Checks if cononical namespace name exists for namespace
4324                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
4325                         // Uses canonical namespace name
4326                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
4327                 } else {
4328                         // Uses text of namespace
4329                         $namespaceKey = $this->getSubjectNsText();
4330                 }
4331                 // Makes namespace key lowercase
4332                 $namespaceKey = $wgContLang->lc( $namespaceKey );
4333                 // Uses main
4334                 if ( $namespaceKey == '' ) {
4335                         $namespaceKey = 'main';
4336                 }
4337                 // Changes file to image for backwards compatibility
4338                 if ( $namespaceKey == 'file' ) {
4339                         $namespaceKey = 'image';
4340                 }
4341                 return $prepend . $namespaceKey;
4342         }
4343
4344         /**
4345          * Get all extant redirects to this Title
4346          *
4347          * @param $ns Int|Null Single namespace to consider; NULL to consider all namespaces
4348          * @return Array of Title redirects to this title
4349          */
4350         public function getRedirectsHere( $ns = null ) {
4351                 $redirs = array();
4352
4353                 $dbr = wfGetDB( DB_SLAVE );
4354                 $where = array(
4355                         'rd_namespace' => $this->getNamespace(),
4356                         'rd_title' => $this->getDBkey(),
4357                         'rd_from = page_id'
4358                 );
4359                 if ( !is_null( $ns ) ) {
4360                         $where['page_namespace'] = $ns;
4361                 }
4362
4363                 $res = $dbr->select(
4364                         array( 'redirect', 'page' ),
4365                         array( 'page_namespace', 'page_title' ),
4366                         $where,
4367                         __METHOD__
4368                 );
4369
4370                 foreach ( $res as $row ) {
4371                         $redirs[] = self::newFromRow( $row );
4372                 }
4373                 return $redirs;
4374         }
4375
4376         /**
4377          * Check if this Title is a valid redirect target
4378          *
4379          * @return Bool
4380          */
4381         public function isValidRedirectTarget() {
4382                 global $wgInvalidRedirectTargets;
4383
4384                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
4385                 if ( $this->isSpecial( 'Userlogout' ) ) {
4386                         return false;
4387                 }
4388
4389                 foreach ( $wgInvalidRedirectTargets as $target ) {
4390                         if ( $this->isSpecial( $target ) ) {
4391                                 return false;
4392                         }
4393                 }
4394
4395                 return true;
4396         }
4397
4398         /**
4399          * Get a backlink cache object
4400          *
4401          * @return BacklinkCache
4402          */
4403         function getBacklinkCache() {
4404                 if ( is_null( $this->mBacklinkCache ) ) {
4405                         $this->mBacklinkCache = new BacklinkCache( $this );
4406                 }
4407                 return $this->mBacklinkCache;
4408         }
4409
4410         /**
4411          * Whether the magic words __INDEX__ and __NOINDEX__ function for  this page.
4412          *
4413          * @return Boolean
4414          */
4415         public function canUseNoindex() {
4416                 global $wgContentNamespaces, $wgExemptFromUserRobotsControl;
4417
4418                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
4419                         ? $wgContentNamespaces
4420                         : $wgExemptFromUserRobotsControl;
4421
4422                 return !in_array( $this->mNamespace, $bannedNamespaces );
4423
4424         }
4425
4426         /**
4427          * Returns the raw sort key to be used for categories, with the specified
4428          * prefix.  This will be fed to Collation::getSortKey() to get a
4429          * binary sortkey that can be used for actual sorting.
4430          *
4431          * @param $prefix string The prefix to be used, specified using
4432          *   {{defaultsort:}} or like [[Category:Foo|prefix]].  Empty for no
4433          *   prefix.
4434          * @return string
4435          */
4436         public function getCategorySortkey( $prefix = '' ) {
4437                 $unprefixed = $this->getText();
4438
4439                 // Anything that uses this hook should only depend
4440                 // on the Title object passed in, and should probably
4441                 // tell the users to run updateCollations.php --force
4442                 // in order to re-sort existing category relations.
4443                 wfRunHooks( 'GetDefaultSortkey', array( $this, &$unprefixed ) );
4444                 if ( $prefix !== '' ) {
4445                         # Separate with a line feed, so the unprefixed part is only used as
4446                         # a tiebreaker when two pages have the exact same prefix.
4447                         # In UCA, tab is the only character that can sort above LF
4448                         # so we strip both of them from the original prefix.
4449                         $prefix = strtr( $prefix, "\n\t", '  ' );
4450                         return "$prefix\n$unprefixed";
4451                 }
4452                 return $unprefixed;
4453         }
4454
4455         /**
4456          * Get the language in which the content of this page is written.
4457          * Defaults to $wgContLang, but in certain cases it can be e.g.
4458          * $wgLang (such as special pages, which are in the user language).
4459          *
4460          * @since 1.18
4461          * @return object Language
4462          */
4463         public function getPageLanguage() {
4464                 global $wgLang;
4465                 if ( $this->isSpecialPage() ) {
4466                         // special pages are in the user language
4467                         return $wgLang;
4468                 } elseif ( $this->isCssOrJsPage() ) {
4469                         // css/js should always be LTR and is, in fact, English
4470                         return wfGetLangObj( 'en' );
4471                 } elseif ( $this->getNamespace() == NS_MEDIAWIKI ) {
4472                         // Parse mediawiki messages with correct target language
4473                         list( /* $unused */, $lang ) = MessageCache::singleton()->figureMessage( $this->getText() );
4474                         return wfGetLangObj( $lang );
4475                 }
4476                 global $wgContLang;
4477                 // If nothing special, it should be in the wiki content language
4478                 $pageLang = $wgContLang;
4479                 // Hook at the end because we don't want to override the above stuff
4480                 wfRunHooks( 'PageContentLanguage', array( $this, &$pageLang, $wgLang ) );
4481                 return wfGetLangObj( $pageLang );
4482         }
4483 }