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          * Trim down a .css or .js subpage title to get the corresponding skin name
 971          *
 972          * @return string containing skin name from .css or .js subpage title
 973          */
 974         public function getSkinFromCssJsSubpage() {
 975                 $subpage = explode( '/', $this->mTextform );
 976                 $subpage = $subpage[ count( $subpage ) - 1 ];
 977                 $lastdot = strrpos( $subpage, '.' );
 978                 if ( $lastdot === false )
 979                         return $subpage; # Never happens: only called for names ending in '.css' or '.js'
 980                 return substr( $subpage, 0, $lastdot );
 981         }
 982
 983         /**
 984          * Is this a .css subpage of a user page?
 985          *
 986          * @return Bool
 987          */
 988         public function isCssSubpage() {
 989                 return ( NS_USER == $this->mNamespace && preg_match( "/\\/.*\\.css$/", $this->mTextform ) );
 990         }
 991
 992         /**
 993          * Is this a .js subpage of a user page?
 994          *
 995          * @return Bool
 996          */
 997         public function isJsSubpage() {
 998                 return ( NS_USER == $this->mNamespace && preg_match( "/\\/.*\\.js$/", $this->mTextform ) );
 999         }
1000
1001         /**
1002          * Is this a talk page of some sort?
1003          *
1004          * @return Bool
1005          */
1006         public function isTalkPage() {
1007                 return MWNamespace::isTalk( $this->getNamespace() );
1008         }
1009
1010         /**
1011          * Get a Title object associated with the talk page of this article
1012          *
1013          * @return Title the object for the talk page
1014          */
1015         public function getTalkPage() {
1016                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1017         }
1018
1019         /**
1020          * Get a title object associated with the subject page of this
1021          * talk page
1022          *
1023          * @return Title the object for the subject page
1024          */
1025         public function getSubjectPage() {
1026                 // Is this the same title?
1027                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
1028                 if ( $this->getNamespace() == $subjectNS ) {
1029                         return $this;
1030                 }
1031                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
1032         }
1033
1034         /**
1035          * Get the default namespace index, for when there is no namespace
1036          *
1037          * @return Int Default namespace index
1038          */
1039         public function getDefaultNamespace() {
1040                 return $this->mDefaultNamespace;
1041         }
1042
1043         /**
1044          * Get title for search index
1045          *
1046          * @return String a stripped-down title string ready for the
1047          *  search index
1048          */
1049         public function getIndexTitle() {
1050                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
1051         }
1052
1053         /**
1054          * Get the Title fragment (i.e.\ the bit after the #) in text form
1055          *
1056          * @return String Title fragment
1057          */
1058         public function getFragment() {
1059                 return $this->mFragment;
1060         }
1061
1062         /**
1063          * Get the fragment in URL form, including the "#" character if there is one
1064          * @return String Fragment in URL form
1065          */
1066         public function getFragmentForURL() {
1067                 if ( $this->mFragment == '' ) {
1068                         return '';
1069                 } else {
1070                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
1071                 }
1072         }
1073
1074         /**
1075          * Set the fragment for this title. Removes the first character from the
1076          * specified fragment before setting, so it assumes you're passing it with
1077          * an initial "#".
1078          *
1079          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
1080          * Still in active use privately.
1081          *
1082          * @param $fragment String text
1083          */
1084         public function setFragment( $fragment ) {
1085                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
1086         }
1087
1088         /**
1089          * Prefix some arbitrary text with the namespace or interwiki prefix
1090          * of this object
1091          *
1092          * @param $name String the text
1093          * @return String the prefixed text
1094          * @private
1095          */
1096         private function prefix( $name ) {
1097                 $p = '';
1098                 if ( $this->mInterwiki != '' ) {
1099                         $p = $this->mInterwiki . ':';
1100                 }
1101
1102                 if ( 0 != $this->mNamespace ) {
1103                         $p .= $this->getNsText() . ':';
1104                 }
1105                 return $p . $name;
1106         }
1107
1108         /**
1109          * Get the prefixed database key form
1110          *
1111          * @return String the prefixed title, with underscores and
1112          *  any interwiki and namespace prefixes
1113          */
1114         public function getPrefixedDBkey() {
1115                 $s = $this->prefix( $this->mDbkeyform );
1116                 $s = str_replace( ' ', '_', $s );
1117                 return $s;
1118         }
1119
1120         /**
1121          * Get the prefixed title with spaces.
1122          * This is the form usually used for display
1123          *
1124          * @return String the prefixed title, with spaces
1125          */
1126         public function getPrefixedText() {
1127                 // @todo FIXME: Bad usage of empty() ?
1128                 if ( empty( $this->mPrefixedText ) ) {
1129                         $s = $this->prefix( $this->mTextform );
1130                         $s = str_replace( '_', ' ', $s );
1131                         $this->mPrefixedText = $s;
1132                 }
1133                 return $this->mPrefixedText;
1134         }
1135
1136         /**
1137          * Return a string representation of this title
1138          *
1139          * @return String representation of this title
1140          */
1141         public function __toString() {
1142                 return $this->getPrefixedText();
1143         }
1144
1145         /**
1146          * Get the prefixed title with spaces, plus any fragment
1147          * (part beginning with '#')
1148          *
1149          * @return String the prefixed title, with spaces and the fragment, including '#'
1150          */
1151         public function getFullText() {
1152                 $text = $this->getPrefixedText();
1153                 if ( $this->mFragment != '' ) {
1154                         $text .= '#' . $this->mFragment;
1155                 }
1156                 return $text;
1157         }
1158
1159         /**
1160          * Get the base page name, i.e. the leftmost part before any slashes
1161          *
1162          * @return String Base name
1163          */
1164         public function getBaseText() {
1165                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1166                         return $this->getText();
1167                 }
1168
1169                 $parts = explode( '/', $this->getText() );
1170                 # Don't discard the real title if there's no subpage involved
1171                 if ( count( $parts ) > 1 ) {
1172                         unset( $parts[count( $parts ) - 1] );
1173                 }
1174                 return implode( '/', $parts );
1175         }
1176
1177         /**
1178          * Get the lowest-level subpage name, i.e. the rightmost part after any slashes
1179          *
1180          * @return String Subpage name
1181          */
1182         public function getSubpageText() {
1183                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1184                         return( $this->mTextform );
1185                 }
1186                 $parts = explode( '/', $this->mTextform );
1187                 return( $parts[count( $parts ) - 1] );
1188         }
1189
1190         /**
1191          * Get the HTML-escaped displayable text form.
1192          * Used for the title field in <a> tags.
1193          *
1194          * @return String the text, including any prefixes
1195          */
1196         public function getEscapedText() {
1197                 wfDeprecated( __METHOD__, '1.19' );
1198                 return htmlspecialchars( $this->getPrefixedText() );
1199         }
1200
1201         /**
1202          * Get a URL-encoded form of the subpage text
1203          *
1204          * @return String URL-encoded subpage name
1205          */
1206         public function getSubpageUrlForm() {
1207                 $text = $this->getSubpageText();
1208                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
1209                 return( $text );
1210         }
1211
1212         /**
1213          * Get a URL-encoded title (not an actual URL) including interwiki
1214          *
1215          * @return String the URL-encoded form
1216          */
1217         public function getPrefixedURL() {
1218                 $s = $this->prefix( $this->mDbkeyform );
1219                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
1220                 return $s;
1221         }
1222
1223         /**
1224          * Helper to fix up the get{Local,Full,Link,Canonical}URL args
1225          */
1226         private static function fixUrlQueryArgs( $query, $query2 ) {
1227                 if ( is_array( $query ) ) {
1228                         $query = wfArrayToCGI( $query );
1229                 }
1230                 if ( $query2 ) {
1231                         if ( is_string( $query2 ) ) {
1232                                 // $query2 is a string, we will consider this to be
1233                                 // a deprecated $variant argument and add it to the query
1234                                 $query2 = wfArrayToCGI( array( 'variant' => $query2 ) );
1235                         } else {
1236                                 $query2 = wfArrayToCGI( $query2 );
1237                         }
1238                         // If we have $query content add a & to it first
1239                         if ( $query ) {
1240                                 $query .= '&';
1241                         }
1242                         // Now append the queries together
1243                         $query .= $query2;
1244                 }
1245                 return $query;
1246         }
1247
1248         /**
1249          * Get a real URL referring to this title, with interwiki link and
1250          * fragment
1251          *
1252          * See getLocalURL for the arguments.
1253          *
1254          * @see self::getLocalURL
1255          * @return String the URL
1256          */
1257         public function getFullURL( $query = '', $query2 = false ) {
1258                 $query = self::fixUrlQueryArgs( $query, $query2 );
1259
1260                 # Hand off all the decisions on urls to getLocalURL
1261                 $url = $this->getLocalURL( $query );
1262
1263                 # Expand the url to make it a full url. Note that getLocalURL has the
1264                 # potential to output full urls for a variety of reasons, so we use
1265                 # wfExpandUrl instead of simply prepending $wgServer
1266                 $url = wfExpandUrl( $url, PROTO_RELATIVE );
1267
1268                 # Finally, add the fragment.
1269                 $url .= $this->getFragmentForURL();
1270
1271                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
1272                 return $url;
1273         }
1274
1275         /**
1276          * Get a URL with no fragment or server name.  If this page is generated
1277          * with action=render, $wgServer is prepended.
1278          *
1279
1280          * @param $query \twotypes{\string,\array} an optional query string,
1281          *   not used for interwiki     links. Can be specified as an associative array as well,
1282          *   e.g., array( 'action' => 'edit' ) (keys and values will be URL-escaped).
1283          *   Some query patterns will trigger various shorturl path replacements.
1284          * @param $query2 Mixed: An optional secondary query array. This one MUST
1285          *   be an array. If a string is passed it will be interpreted as a deprecated
1286          *   variant argument and urlencoded into a variant= argument.
1287          *   This second query argument will be added to the $query
1288          * @return String the URL
1289          */
1290         public function getLocalURL( $query = '', $query2 = false ) {
1291                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
1292
1293                 $query = self::fixUrlQueryArgs( $query, $query2 );
1294
1295                 $interwiki = Interwiki::fetch( $this->mInterwiki );
1296                 if ( $interwiki ) {
1297                         $namespace = $this->getNsText();
1298                         if ( $namespace != '' ) {
1299                                 # Can this actually happen? Interwikis shouldn't be parsed.
1300                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
1301                                 $namespace .= ':';
1302                         }
1303                         $url = $interwiki->getURL( $namespace . $this->getDBkey() );
1304                         $url = wfAppendQuery( $url, $query );
1305                 } else {
1306                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
1307                         if ( $query == '' ) {
1308                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
1309                                 wfRunHooks( 'GetLocalURL::Article', array( &$this, &$url ) );
1310                         } else {
1311                                 global $wgVariantArticlePath, $wgActionPaths;
1312                                 $url = false;
1313                                 $matches = array();
1314
1315                                 if ( !empty( $wgActionPaths ) &&
1316                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
1317                                 {
1318                                         $action = urldecode( $matches[2] );
1319                                         if ( isset( $wgActionPaths[$action] ) ) {
1320                                                 $query = $matches[1];
1321                                                 if ( isset( $matches[4] ) ) {
1322                                                         $query .= $matches[4];
1323                                                 }
1324                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
1325                                                 if ( $query != '' ) {
1326                                                         $url = wfAppendQuery( $url, $query );
1327                                                 }
1328                                         }
1329                                 }
1330
1331                                 if ( $url === false &&
1332                                         $wgVariantArticlePath &&
1333                                         $this->getPageLanguage()->hasVariants() &&
1334                                         preg_match( '/^variant=([^&]*)$/', $query, $matches ) )
1335                                 {
1336                                         $variant = urldecode( $matches[1] );
1337                                         if ( $this->getPageLanguage()->hasVariant( $variant ) ) {
1338                                                 // Only do the variant replacement if the given variant is a valid
1339                                                 // variant for the page's language.
1340                                                 $url = str_replace( '$2', urlencode( $variant ), $wgVariantArticlePath );
1341                                                 $url = str_replace( '$1', $dbkey, $url );
1342                                         }
1343                                 }
1344
1345                                 if ( $url === false ) {
1346                                         if ( $query == '-' ) {
1347                                                 $query = '';
1348                                         }
1349                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
1350                                 }
1351                         }
1352
1353                         wfRunHooks( 'GetLocalURL::Internal', array( &$this, &$url, $query ) );
1354
1355                         // @todo FIXME: This causes breakage in various places when we
1356                         // actually expected a local URL and end up with dupe prefixes.
1357                         if ( $wgRequest->getVal( 'action' ) == 'render' ) {
1358                                 $url = $wgServer . $url;
1359                         }
1360                 }
1361                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
1362                 return $url;
1363         }
1364
1365         /**
1366          * Get a URL that's the simplest URL that will be valid to link, locally,
1367          * to the current Title.  It includes the fragment, but does not include
1368          * the server unless action=render is used (or the link is external).  If
1369          * there's a fragment but the prefixed text is empty, we just return a link
1370          * to the fragment.
1371          *
1372          * The result obviously should not be URL-escaped, but does need to be
1373          * HTML-escaped if it's being output in HTML.
1374          *
1375          * See getLocalURL for the arguments.
1376          *
1377          * @see self::getLocalURL
1378          * @return String the URL
1379          */
1380         public function getLinkURL( $query = '', $query2 = false ) {
1381                 wfProfileIn( __METHOD__ );
1382                 if ( $this->isExternal() ) {
1383                         $ret = $this->getFullURL( $query, $query2 );
1384                 } elseif ( $this->getPrefixedText() === '' && $this->getFragment() !== '' ) {
1385                         $ret = $this->getFragmentForURL();
1386                 } else {
1387                         $ret = $this->getLocalURL( $query, $query2 ) . $this->getFragmentForURL();
1388                 }
1389                 wfProfileOut( __METHOD__ );
1390                 return $ret;
1391         }
1392
1393         /**
1394          * Get an HTML-escaped version of the URL form, suitable for
1395          * using in a link, without a server name or fragment
1396          *
1397          * See getLocalURL for the arguments.
1398          *
1399          * @see self::getLocalURL
1400          * @return String the URL
1401          */
1402         public function escapeLocalURL( $query = '', $query2 = false ) {
1403                 wfDeprecated( __METHOD__, '1.19' );
1404                 return htmlspecialchars( $this->getLocalURL( $query, $query2 ) );
1405         }
1406
1407         /**
1408          * Get an HTML-escaped version of the URL form, suitable for
1409          * using in a link, including the server name and fragment
1410          *
1411          * See getLocalURL for the arguments.
1412          *
1413          * @see self::getLocalURL
1414          * @return String the URL
1415          */
1416         public function escapeFullURL( $query = '', $query2 = false ) {
1417                 wfDeprecated( __METHOD__, '1.19' );
1418                 return htmlspecialchars( $this->getFullURL( $query, $query2 ) );
1419         }
1420
1421         /**
1422          * Get the URL form for an internal link.
1423          * - Used in various Squid-related code, in case we have a different
1424          * internal hostname for the server from the exposed one.
1425          *
1426          * This uses $wgInternalServer to qualify the path, or $wgServer
1427          * if $wgInternalServer is not set. If the server variable used is
1428          * protocol-relative, the URL will be expanded to http://
1429          *
1430          * See getLocalURL for the arguments.
1431          *
1432          * @see self::getLocalURL
1433          * @return String the URL
1434          */
1435         public function getInternalURL( $query = '', $query2 = false ) {
1436                 global $wgInternalServer, $wgServer;
1437                 $query = self::fixUrlQueryArgs( $query, $query2 );
1438                 $server = $wgInternalServer !== false ? $wgInternalServer : $wgServer;
1439                 $url = wfExpandUrl( $server . $this->getLocalURL( $query ), PROTO_HTTP );
1440                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
1441                 return $url;
1442         }
1443
1444         /**
1445          * Get the URL for a canonical link, for use in things like IRC and
1446          * e-mail notifications. Uses $wgCanonicalServer and the
1447          * GetCanonicalURL hook.
1448          *
1449          * NOTE: Unlike getInternalURL(), the canonical URL includes the fragment
1450          *
1451          * See getLocalURL for the arguments.
1452          *
1453          * @see self::getLocalURL
1454          * @return string The URL
1455          * @since 1.18
1456          */
1457         public function getCanonicalURL( $query = '', $query2 = false ) {
1458                 $query = self::fixUrlQueryArgs( $query, $query2 );
1459                 $url = wfExpandUrl( $this->getLocalURL( $query ) . $this->getFragmentForURL(), PROTO_CANONICAL );
1460                 wfRunHooks( 'GetCanonicalURL', array( &$this, &$url, $query ) );
1461                 return $url;
1462         }
1463
1464         /**
1465          * HTML-escaped version of getCanonicalURL()
1466          *
1467          * See getLocalURL for the arguments.
1468          *
1469          * @see self::getLocalURL
1470          * @since 1.18
1471          */
1472         public function escapeCanonicalURL( $query = '', $query2 = false ) {
1473                 wfDeprecated( __METHOD__, '1.19' );
1474                 return htmlspecialchars( $this->getCanonicalURL( $query, $query2 ) );
1475         }
1476
1477         /**
1478          * Get the edit URL for this Title
1479          *
1480          * @return String the URL, or a null string if this is an
1481          *  interwiki link
1482          */
1483         public function getEditURL() {
1484                 if ( $this->mInterwiki != '' ) {
1485                         return '';
1486                 }
1487                 $s = $this->getLocalURL( 'action=edit' );
1488
1489                 return $s;
1490         }
1491
1492         /**
1493          * Is $wgUser watching this page?
1494          *
1495          * @return Bool
1496          */
1497         public function userIsWatching() {
1498                 global $wgUser;
1499
1500                 if ( is_null( $this->mWatched ) ) {
1501                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn() ) {
1502                                 $this->mWatched = false;
1503                         } else {
1504                                 $this->mWatched = $wgUser->isWatched( $this );
1505                         }
1506                 }
1507                 return $this->mWatched;
1508         }
1509
1510         /**
1511          * Can $wgUser read this page?
1512          *
1513          * @deprecated in 1.19; use userCan(), quickUserCan() or getUserPermissionsErrors() instead
1514          * @return Bool
1515          * @todo fold these checks into userCan()
1516          */
1517         public function userCanRead() {
1518                 wfDeprecated( __METHOD__, '1.19' );
1519                 return $this->userCan( 'read' );
1520         }
1521
1522         /**
1523          * Can $user perform $action on this page?
1524          * This skips potentially expensive cascading permission checks
1525          * as well as avoids expensive error formatting
1526          *
1527          * Suitable for use for nonessential UI controls in common cases, but
1528          * _not_ for functional access control.
1529          *
1530          * May provide false positives, but should never provide a false negative.
1531          *
1532          * @param $action String action that permission needs to be checked for
1533          * @param $user User to check (since 1.19); $wgUser will be used if not
1534          *              provided.
1535          * @return Bool
1536          */
1537         public function quickUserCan( $action, $user = null ) {
1538                 return $this->userCan( $action, $user, false );
1539         }
1540
1541         /**
1542          * Can $user perform $action on this page?
1543          *
1544          * @param $action String action that permission needs to be checked for
1545          * @param $user User to check (since 1.19); $wgUser will be used if not
1546          *   provided.
1547          * @param $doExpensiveQueries Bool Set this to false to avoid doing
1548          *   unnecessary queries.
1549          * @return Bool
1550          */
1551         public function userCan( $action, $user = null, $doExpensiveQueries = true ) {
1552                 if ( !$user instanceof User ) {
1553                         global $wgUser;
1554                         $user = $wgUser;
1555                 }
1556                 return !count( $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries, true ) );
1557         }
1558
1559         /**
1560          * Can $user perform $action on this page?
1561          *
1562          * @todo FIXME: This *does not* check throttles (User::pingLimiter()).
1563          *
1564          * @param $action String action that permission needs to be checked for
1565          * @param $user User to check
1566          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary
1567          *   queries by skipping checks for cascading protections and user blocks.
1568          * @param $ignoreErrors Array of Strings Set this to a list of message keys
1569          *   whose corresponding errors may be ignored.
1570          * @return Array of arguments to wfMsg to explain permissions problems.
1571          */
1572         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1573                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1574
1575                 // Remove the errors being ignored.
1576                 foreach ( $errors as $index => $error ) {
1577                         $error_key = is_array( $error ) ? $error[0] : $error;
1578
1579                         if ( in_array( $error_key, $ignoreErrors ) ) {
1580                                 unset( $errors[$index] );
1581                         }
1582                 }
1583
1584                 return $errors;
1585         }
1586
1587         /**
1588          * Permissions checks that fail most often, and which are easiest to test.
1589          *
1590          * @param $action String the action to check
1591          * @param $user User user to check
1592          * @param $errors Array list of current errors
1593          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1594          * @param $short Boolean short circuit on first error
1595          *
1596          * @return Array list of errors
1597          */
1598         private function checkQuickPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1599                 if ( $action == 'create' ) {
1600                         if ( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1601                                  ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1602                                 $errors[] = $user->isAnon() ? array( 'nocreatetext' ) : array( 'nocreate-loggedin' );
1603                         }
1604                 } elseif ( $action == 'move' ) {
1605                         if ( !$user->isAllowed( 'move-rootuserpages' )
1606                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1607                                 // Show user page-specific message only if the user can move other pages
1608                                 $errors[] = array( 'cant-move-user-page' );
1609                         }
1610
1611                         // Check if user is allowed to move files if it's a file
1612                         if ( $this->mNamespace == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1613                                 $errors[] = array( 'movenotallowedfile' );
1614                         }
1615
1616                         if ( !$user->isAllowed( 'move' ) ) {
1617                                 // User can't move anything
1618                                 global $wgGroupPermissions;
1619                                 $userCanMove = false;
1620                                 if ( isset( $wgGroupPermissions['user']['move'] ) ) {
1621                                         $userCanMove = $wgGroupPermissions['user']['move'];
1622                                 }
1623                                 $autoconfirmedCanMove = false;
1624                                 if ( isset( $wgGroupPermissions['autoconfirmed']['move'] ) ) {
1625                                         $autoconfirmedCanMove = $wgGroupPermissions['autoconfirmed']['move'];
1626                                 }
1627                                 if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
1628                                         // custom message if logged-in users without any special rights can move
1629                                         $errors[] = array( 'movenologintext' );
1630                                 } else {
1631                                         $errors[] = array( 'movenotallowed' );
1632                                 }
1633                         }
1634                 } elseif ( $action == 'move-target' ) {
1635                         if ( !$user->isAllowed( 'move' ) ) {
1636                                 // User can't move anything
1637                                 $errors[] = array( 'movenotallowed' );
1638                         } elseif ( !$user->isAllowed( 'move-rootuserpages' )
1639                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1640                                 // Show user page-specific message only if the user can move other pages
1641                                 $errors[] = array( 'cant-move-to-user-page' );
1642                         }
1643                 } elseif ( !$user->isAllowed( $action ) ) {
1644                         $errors[] = $this->missingPermissionError( $action, $short );
1645                 }
1646
1647                 return $errors;
1648         }
1649
1650         /**
1651          * Add the resulting error code to the errors array
1652          *
1653          * @param $errors Array list of current errors
1654          * @param $result Mixed result of errors
1655          *
1656          * @return Array list of errors
1657          */
1658         private function resultToError( $errors, $result ) {
1659                 if ( is_array( $result ) && count( $result ) && !is_array( $result[0] ) ) {
1660                         // A single array representing an error
1661                         $errors[] = $result;
1662                 } elseif ( is_array( $result ) && is_array( $result[0] ) ) {
1663                         // A nested array representing multiple errors
1664                         $errors = array_merge( $errors, $result );
1665                 } elseif ( $result !== '' && is_string( $result ) ) {
1666                         // A string representing a message-id
1667                         $errors[] = array( $result );
1668                 } elseif ( $result === false ) {
1669                         // a generic "We don't want them to do that"
1670                         $errors[] = array( 'badaccess-group0' );
1671                 }
1672                 return $errors;
1673         }
1674
1675         /**
1676          * Check various permission hooks
1677          *
1678          * @param $action String the action to check
1679          * @param $user User user to check
1680          * @param $errors Array list of current errors
1681          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1682          * @param $short Boolean short circuit on first error
1683          *
1684          * @return Array list of errors
1685          */
1686         private function checkPermissionHooks( $action, $user, $errors, $doExpensiveQueries, $short ) {
1687                 // Use getUserPermissionsErrors instead
1688                 $result = '';
1689                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1690                         return $result ? array() : array( array( 'badaccess-group0' ) );
1691                 }
1692                 // Check getUserPermissionsErrors hook
1693                 if ( !wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1694                         $errors = $this->resultToError( $errors, $result );
1695                 }
1696                 // Check getUserPermissionsErrorsExpensive hook
1697                 if ( $doExpensiveQueries && !( $short && count( $errors ) > 0 ) &&
1698                          !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) ) ) {
1699                         $errors = $this->resultToError( $errors, $result );
1700                 }
1701
1702                 return $errors;
1703         }
1704
1705         /**
1706          * Check permissions on special pages & namespaces
1707          *
1708          * @param $action String the action to check
1709          * @param $user User user to check
1710          * @param $errors Array list of current errors
1711          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1712          * @param $short Boolean short circuit on first error
1713          *
1714          * @return Array list of errors
1715          */
1716         private function checkSpecialsAndNSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1717                 # Only 'createaccount' and 'execute' can be performed on
1718                 # special pages, which don't actually exist in the DB.
1719                 $specialOKActions = array( 'createaccount', 'execute', 'read' );
1720                 if ( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions ) ) {
1721                         $errors[] = array( 'ns-specialprotected' );
1722                 }
1723
1724                 # Check $wgNamespaceProtection for restricted namespaces
1725                 if ( $this->isNamespaceProtected( $user ) ) {
1726                         $ns = $this->mNamespace == NS_MAIN ?
1727                                 wfMsg( 'nstab-main' ) : $this->getNsText();
1728                         $errors[] = $this->mNamespace == NS_MEDIAWIKI ?
1729                                 array( 'protectedinterface' ) : array( 'namespaceprotected',  $ns );
1730                 }
1731
1732                 return $errors;
1733         }
1734
1735         /**
1736          * Check CSS/JS sub-page permissions
1737          *
1738          * @param $action String the action to check
1739          * @param $user User user to check
1740          * @param $errors Array list of current errors
1741          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1742          * @param $short Boolean short circuit on first error
1743          *
1744          * @return Array list of errors
1745          */
1746         private function checkCSSandJSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1747                 # Protect css/js subpages of user pages
1748                 # XXX: this might be better using restrictions
1749                 # XXX: right 'editusercssjs' is deprecated, for backward compatibility only
1750                 if ( $action != 'patrol' && !$user->isAllowed( 'editusercssjs' )
1751                                 && !preg_match( '/^' . preg_quote( $user->getName(), '/' ) . '\//', $this->mTextform ) ) {
1752                         if ( $this->isCssSubpage() && !$user->isAllowed( 'editusercss' ) ) {
1753                                 $errors[] = array( 'customcssprotected' );
1754                         } elseif ( $this->isJsSubpage() && !$user->isAllowed( 'edituserjs' ) ) {
1755                                 $errors[] = array( 'customjsprotected' );
1756                         }
1757                 }
1758
1759                 return $errors;
1760         }
1761
1762         /**
1763          * Check against page_restrictions table requirements on this
1764          * page. The user must possess all required rights for this
1765          * action.
1766          *
1767          * @param $action String the action to check
1768          * @param $user User user to check
1769          * @param $errors Array list of current errors
1770          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1771          * @param $short Boolean short circuit on first error
1772          *
1773          * @return Array list of errors
1774          */
1775         private function checkPageRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1776                 foreach ( $this->getRestrictions( $action ) as $right ) {
1777                         // Backwards compatibility, rewrite sysop -> protect
1778                         if ( $right == 'sysop' ) {
1779                                 $right = 'protect';
1780                         }
1781                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1782                                 // Users with 'editprotected' permission can edit protected pages
1783                                 // without cascading option turned on.
1784                                 if ( $action != 'edit' || !$user->isAllowed( 'editprotected' )
1785                                         || $this->mCascadeRestriction )
1786                                 {
1787                                         $errors[] = array( 'protectedpagetext', $right );
1788                                 }
1789                         }
1790                 }
1791
1792                 return $errors;
1793         }
1794
1795         /**
1796          * Check restrictions on cascading pages.
1797          *
1798          * @param $action String the action to check
1799          * @param $user User to check
1800          * @param $errors Array list of current errors
1801          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1802          * @param $short Boolean short circuit on first error
1803          *
1804          * @return Array list of errors
1805          */
1806         private function checkCascadingSourcesRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1807                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1808                         # We /could/ use the protection level on the source page, but it's
1809                         # fairly ugly as we have to establish a precedence hierarchy for pages
1810                         # included by multiple cascade-protected pages. So just restrict
1811                         # it to people with 'protect' permission, as they could remove the
1812                         # protection anyway.
1813                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1814                         # Cascading protection depends on more than this page...
1815                         # Several cascading protected pages may include this page...
1816                         # Check each cascading level
1817                         # This is only for protection restrictions, not for all actions
1818                         if ( isset( $restrictions[$action] ) ) {
1819                                 foreach ( $restrictions[$action] as $right ) {
1820                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1821                                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1822                                                 $pages = '';
1823                                                 foreach ( $cascadingSources as $page )
1824                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1825                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1826                                         }
1827                                 }
1828                         }
1829                 }
1830
1831                 return $errors;
1832         }
1833
1834         /**
1835          * Check action permissions not already checked in checkQuickPermissions
1836          *
1837          * @param $action String the action to check
1838          * @param $user User to check
1839          * @param $errors Array list of current errors
1840          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1841          * @param $short Boolean short circuit on first error
1842          *
1843          * @return Array list of errors
1844          */
1845         private function checkActionPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1846                 if ( $action == 'protect' ) {
1847                         if ( count( $this->getUserPermissionsErrorsInternal( 'edit', $user, $doExpensiveQueries, true ) ) ) {
1848                                 // If they can't edit, they shouldn't protect.
1849                                 $errors[] = array( 'protect-cantedit' );
1850                         }
1851                 } elseif ( $action == 'create' ) {
1852                         $title_protection = $this->getTitleProtection();
1853                         if( $title_protection ) {
1854                                 if( $title_protection['pt_create_perm'] == 'sysop' ) {
1855                                         $title_protection['pt_create_perm'] = 'protect'; // B/C
1856                                 }
1857                                 if( $title_protection['pt_create_perm'] == '' ||
1858                                         !$user->isAllowed( $title_protection['pt_create_perm'] ) )
1859                                 {
1860                                         $errors[] = array( 'titleprotected', User::whoIs( $title_protection['pt_user'] ), $title_protection['pt_reason'] );
1861                                 }
1862                         }
1863                 } elseif ( $action == 'move' ) {
1864                         // Check for immobile pages
1865                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1866                                 // Specific message for this case
1867                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1868                         } elseif ( !$this->isMovable() ) {
1869                                 // Less specific message for rarer cases
1870                                 $errors[] = array( 'immobile-source-page' );
1871                         }
1872                 } elseif ( $action == 'move-target' ) {
1873                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1874                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1875                         } elseif ( !$this->isMovable() ) {
1876                                 $errors[] = array( 'immobile-target-page' );
1877                         }
1878                 }
1879                 return $errors;
1880         }
1881
1882         /**
1883          * Check that the user isn't blocked from editting.
1884          *
1885          * @param $action String the action to check
1886          * @param $user User to check
1887          * @param $errors Array list of current errors
1888          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1889          * @param $short Boolean short circuit on first error
1890          *
1891          * @return Array list of errors
1892          */
1893         private function checkUserBlock( $action, $user, $errors, $doExpensiveQueries, $short ) {
1894                 // Account creation blocks handled at userlogin.
1895                 // Unblocking handled in SpecialUnblock
1896                 if( !$doExpensiveQueries || in_array( $action, array( 'createaccount', 'unblock' ) ) ) {
1897                         return $errors;
1898                 }
1899
1900                 global $wgContLang, $wgLang, $wgEmailConfirmToEdit;
1901
1902                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() ) {
1903                         $errors[] = array( 'confirmedittext' );
1904                 }
1905
1906                 if ( ( $action == 'edit' || $action == 'create' ) && !$user->isBlockedFrom( $this ) ) {
1907                         // Don't block the user from editing their own talk page unless they've been
1908                         // explicitly blocked from that too.
1909                 } elseif( $user->isBlocked() && $user->mBlock->prevents( $action ) !== false ) {
1910                         $block = $user->mBlock;
1911
1912                         // This is from OutputPage::blockedPage
1913                         // Copied at r23888 by werdna
1914
1915                         $id = $user->blockedBy();
1916                         $reason = $user->blockedFor();
1917                         if ( $reason == '' ) {
1918                                 $reason = wfMsg( 'blockednoreason' );
1919                         }
1920                         $ip = $user->getRequest()->getIP();
1921
1922                         if ( is_numeric( $id ) ) {
1923                                 $name = User::whoIs( $id );
1924                         } else {
1925                                 $name = $id;
1926                         }
1927
1928                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1929                         $blockid = $block->getId();
1930                         $blockExpiry = $user->mBlock->mExpiry;
1931                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $user->mBlock->mTimestamp ), true );
1932                         if ( $blockExpiry == 'infinity' ) {
1933                                 $blockExpiry = wfMessage( 'infiniteblock' )->text();
1934                         } else {
1935                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1936                         }
1937
1938                         $intended = strval( $user->mBlock->getTarget() );
1939
1940                         $errors[] = array( ( $block->mAuto ? 'autoblockedtext' : 'blockedtext' ), $link, $reason, $ip, $name,
1941                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
1942                 }
1943
1944                 return $errors;
1945         }
1946
1947         /**
1948          * Check that the user is allowed to read this page.
1949          *
1950          * @param $action String the action to check
1951          * @param $user User to check
1952          * @param $errors Array list of current errors
1953          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1954          * @param $short Boolean short circuit on first error
1955          *
1956          * @return Array list of errors
1957          */
1958         private function checkReadPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1959                 static $useShortcut = null;
1960
1961                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
1962                 if ( is_null( $useShortcut ) ) {
1963                         global $wgGroupPermissions, $wgRevokePermissions;
1964                         $useShortcut = true;
1965                         if ( empty( $wgGroupPermissions['*']['read'] ) ) {
1966                                 # Not a public wiki, so no shortcut
1967                                 $useShortcut = false;
1968                         } elseif ( !empty( $wgRevokePermissions ) ) {
1969                                 /**
1970                                  * Iterate through each group with permissions being revoked (key not included since we don't care
1971                                  * what the group name is), then check if the read permission is being revoked. If it is, then
1972                                  * we don't use the shortcut below since the user might not be able to read, even though anon
1973                                  * reading is allowed.
1974                                  */
1975                                 foreach ( $wgRevokePermissions as $perms ) {
1976                                         if ( !empty( $perms['read'] ) ) {
1977                                                 # We might be removing the read right from the user, so no shortcut
1978                                                 $useShortcut = false;
1979                                                 break;
1980                                         }
1981                                 }
1982                         }
1983                 }
1984
1985                 # Shortcut for public wikis, allows skipping quite a bit of code
1986                 if ( $useShortcut ) {
1987                         return $errors;
1988                 }
1989
1990                 # If the user is allowed to read pages, he is allowed to read all pages
1991                 if ( $user->isAllowed( 'read' ) ) {
1992                         return $errors;
1993                 }
1994
1995                 # Always grant access to the login page.
1996                 # Even anons need to be able to log in.
1997                 if ( $this->isSpecial( 'Userlogin' )
1998                         || $this->isSpecial( 'ChangePassword' )
1999                         || $this->isSpecial( 'PasswordReset' )
2000                 ) {
2001                         return $errors;
2002                 }
2003
2004                 # Time to check the whitelist
2005                 global $wgWhitelistRead;
2006
2007                 # Only to these checks is there's something to check against
2008                 if ( is_array( $wgWhitelistRead ) && count( $wgWhitelistRead ) ) {
2009                         # Check for explicit whitelisting
2010                         $name = $this->getPrefixedText();
2011                         $dbName = $this->getPrefixedDBKey();
2012
2013                         // Check with and without underscores
2014                         if ( in_array( $name, $wgWhitelistRead, true ) || in_array( $dbName, $wgWhitelistRead, true ) ) {
2015                                 return $errors;
2016                         }
2017
2018                         # Old settings might have the title prefixed with
2019                         # a colon for main-namespace pages
2020                         if ( $this->getNamespace() == NS_MAIN ) {
2021                                 if ( in_array( ':' . $name, $wgWhitelistRead ) ) {
2022                                         return $errors;
2023                                 }
2024                         }
2025
2026                         # If it's a special page, ditch the subpage bit and check again
2027                         if ( $this->isSpecialPage() ) {
2028                                 $name = $this->getDBkey();
2029                                 list( $name, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $name );
2030                                 if ( $name !== false ) {
2031                                         $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
2032                                         if ( in_array( $pure, $wgWhitelistRead, true ) ) {
2033                                                 return $errors;
2034                                         }
2035                                 }
2036                         }
2037                 }
2038
2039                 $errors[] = $this->missingPermissionError( $action, $short );
2040                 return $errors;
2041         }
2042
2043         /**
2044          * Get a description array when the user doesn't have the right to perform
2045          * $action (i.e. when User::isAllowed() returns false)
2046          *
2047          * @param $action String the action to check
2048          * @param $short Boolean short circuit on first error
2049          * @return Array list of errors
2050          */
2051         private function missingPermissionError( $action, $short ) {
2052                 // We avoid expensive display logic for quickUserCan's and such
2053                 if ( $short ) {
2054                         return array( 'badaccess-group0' );
2055                 }
2056
2057                 $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
2058                         User::getGroupsWithPermission( $action ) );
2059
2060                 if ( count( $groups ) ) {
2061                         global $wgLang;
2062                         return array(
2063                                 'badaccess-groups',
2064                                 $wgLang->commaList( $groups ),
2065                                 count( $groups )
2066                         );
2067                 } else {
2068                         return array( 'badaccess-group0' );
2069                 }
2070         }
2071
2072         /**
2073          * Can $user perform $action on this page? This is an internal function,
2074          * which checks ONLY that previously checked by userCan (i.e. it leaves out
2075          * checks on wfReadOnly() and blocks)
2076          *
2077          * @param $action String action that permission needs to be checked for
2078          * @param $user User to check
2079          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary queries.
2080          * @param $short Bool Set this to true to stop after the first permission error.
2081          * @return Array of arrays of the arguments to wfMsg to explain permissions problems.
2082          */
2083         protected function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true, $short = false ) {
2084                 wfProfileIn( __METHOD__ );
2085
2086                 # Read has special handling
2087                 if ( $action == 'read' ) {
2088                         $checks = array(
2089                                 'checkPermissionHooks',
2090                                 'checkReadPermissions',
2091                         );
2092                 } else {
2093                         $checks = array(
2094                                 'checkQuickPermissions',
2095                                 'checkPermissionHooks',
2096                                 'checkSpecialsAndNSPermissions',
2097                                 'checkCSSandJSPermissions',
2098                                 'checkPageRestrictions',
2099                                 'checkCascadingSourcesRestrictions',
2100                                 'checkActionPermissions',
2101                                 'checkUserBlock'
2102                         );
2103                 }
2104
2105                 $errors = array();
2106                 while( count( $checks ) > 0 &&
2107                                 !( $short && count( $errors ) > 0 ) ) {
2108                         $method = array_shift( $checks );
2109                         $errors = $this->$method( $action, $user, $errors, $doExpensiveQueries, $short );
2110                 }
2111
2112                 wfProfileOut( __METHOD__ );
2113                 return $errors;
2114         }
2115
2116         /**
2117          * Protect css subpages of user pages: can $wgUser edit
2118          * this page?
2119          *
2120          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2121          * @return Bool
2122          */
2123         public function userCanEditCssSubpage() {
2124                 global $wgUser;
2125                 wfDeprecated( __METHOD__, '1.19' );
2126                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'editusercss' ) )
2127                         || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2128         }
2129
2130         /**
2131          * Protect js subpages of user pages: can $wgUser edit
2132          * this page?
2133          *
2134          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2135          * @return Bool
2136          */
2137         public function userCanEditJsSubpage() {
2138                 global $wgUser;
2139                 wfDeprecated( __METHOD__, '1.19' );
2140                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'edituserjs' ) )
2141                            || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2142         }
2143
2144         /**
2145          * Get a filtered list of all restriction types supported by this wiki.
2146          * @param bool $exists True to get all restriction types that apply to
2147          * titles that do exist, False for all restriction types that apply to
2148          * titles that do not exist
2149          * @return array
2150          */
2151         public static function getFilteredRestrictionTypes( $exists = true ) {
2152                 global $wgRestrictionTypes;
2153                 $types = $wgRestrictionTypes;
2154                 if ( $exists ) {
2155                         # Remove the create restriction for existing titles
2156                         $types = array_diff( $types, array( 'create' ) );
2157                 } else {
2158                         # Only the create and upload restrictions apply to non-existing titles
2159                         $types = array_intersect( $types, array( 'create', 'upload' ) );
2160                 }
2161                 return $types;
2162         }
2163
2164         /**
2165          * Returns restriction types for the current Title
2166          *
2167          * @return array applicable restriction types
2168          */
2169         public function getRestrictionTypes() {
2170                 if ( $this->isSpecialPage() ) {
2171                         return array();
2172                 }
2173
2174                 $types = self::getFilteredRestrictionTypes( $this->exists() );
2175
2176                 if ( $this->getNamespace() != NS_FILE ) {
2177                         # Remove the upload restriction for non-file titles
2178                         $types = array_diff( $types, array( 'upload' ) );
2179                 }
2180
2181                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
2182
2183                 wfDebug( __METHOD__ . ': applicable restrictions to [[' .
2184                         $this->getPrefixedText() . ']] are {' . implode( ',', $types ) . "}\n" );
2185
2186                 return $types;
2187         }
2188
2189         /**
2190          * Is this title subject to title protection?
2191          * Title protection is the one applied against creation of such title.
2192          *
2193          * @return Mixed An associative array representing any existent title
2194          *   protection, or false if there's none.
2195          */
2196         private function getTitleProtection() {
2197                 // Can't protect pages in special namespaces
2198                 if ( $this->getNamespace() < 0 ) {
2199                         return false;
2200                 }
2201
2202                 // Can't protect pages that exist.
2203                 if ( $this->exists() ) {
2204                         return false;
2205                 }
2206
2207                 if ( !isset( $this->mTitleProtection ) ) {
2208                         $dbr = wfGetDB( DB_SLAVE );
2209                         $res = $dbr->select( 'protected_titles', '*',
2210                                 array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2211                                 __METHOD__ );
2212
2213                         // fetchRow returns false if there are no rows.
2214                         $this->mTitleProtection = $dbr->fetchRow( $res );
2215                 }
2216                 return $this->mTitleProtection;
2217         }
2218
2219         /**
2220          * Update the title protection status
2221          *
2222          * @param $create_perm String Permission required for creation
2223          * @param $reason String Reason for protection
2224          * @param $expiry String Expiry timestamp
2225          * @return boolean true
2226          */
2227         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
2228                 global $wgUser, $wgContLang;
2229
2230                 if ( $create_perm == implode( ',', $this->getRestrictions( 'create' ) )
2231                         && $expiry == $this->mRestrictionsExpiry['create'] ) {
2232                         // No change
2233                         return true;
2234                 }
2235
2236                 list ( $namespace, $title ) = array( $this->getNamespace(), $this->getDBkey() );
2237
2238                 $dbw = wfGetDB( DB_MASTER );
2239
2240                 $encodedExpiry = $dbw->encodeExpiry( $expiry );
2241
2242                 $expiry_description = '';
2243                 if ( $encodedExpiry != $dbw->getInfinity() ) {
2244                         $expiry_description = ' (' . wfMsgForContent( 'protect-expiring', $wgContLang->timeanddate( $expiry ),
2245                                 $wgContLang->date( $expiry ) , $wgContLang->time( $expiry ) ) . ')';
2246                 } else {
2247                         $expiry_description .= ' (' . wfMsgForContent( 'protect-expiry-indefinite' ) . ')';
2248                 }
2249
2250                 # Update protection table
2251                 if ( $create_perm != '' ) {
2252                         $this->mTitleProtection = array(
2253                                         'pt_namespace' => $namespace,
2254                                         'pt_title' => $title,
2255                                         'pt_create_perm' => $create_perm,
2256                                         'pt_timestamp' => $dbw->encodeExpiry( wfTimestampNow() ),
2257                                         'pt_expiry' => $encodedExpiry,
2258                                         'pt_user' => $wgUser->getId(),
2259                                         'pt_reason' => $reason,
2260                                 );
2261                         $dbw->replace( 'protected_titles', array( array( 'pt_namespace', 'pt_title' ) ),
2262                                 $this->mTitleProtection, __METHOD__     );
2263                 } else {
2264                         $dbw->delete( 'protected_titles', array( 'pt_namespace' => $namespace,
2265                                 'pt_title' => $title ), __METHOD__ );
2266                         $this->mTitleProtection = false;
2267                 }
2268
2269                 # Update the protection log
2270                 if ( $dbw->affectedRows() ) {
2271                         $log = new LogPage( 'protect' );
2272
2273                         if ( $create_perm ) {
2274                                 $params = array( "[create=$create_perm] $expiry_description", '' );
2275                                 $log->addEntry( ( isset( $this->mRestrictions['create'] ) && $this->mRestrictions['create'] ) ? 'modify' : 'protect', $this, trim( $reason ), $params );
2276                         } else {
2277                                 $log->addEntry( 'unprotect', $this, $reason );
2278                         }
2279                 }
2280
2281                 return true;
2282         }
2283
2284         /**
2285          * Remove any title protection due to page existing
2286          */
2287         public function deleteTitleProtection() {
2288                 $dbw = wfGetDB( DB_MASTER );
2289
2290                 $dbw->delete(
2291                         'protected_titles',
2292                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2293                         __METHOD__
2294                 );
2295                 $this->mTitleProtection = false;
2296         }
2297
2298         /**
2299          * Is this page "semi-protected" - the *only* protection is autoconfirm?
2300          *
2301          * @param $action String Action to check (default: edit)
2302          * @return Bool
2303          */
2304         public function isSemiProtected( $action = 'edit' ) {
2305                 if ( $this->exists() ) {
2306                         $restrictions = $this->getRestrictions( $action );
2307                         if ( count( $restrictions ) > 0 ) {
2308                                 foreach ( $restrictions as $restriction ) {
2309                                         if ( strtolower( $restriction ) != 'autoconfirmed' ) {
2310                                                 return false;
2311                                         }
2312                                 }
2313                         } else {
2314                                 # Not protected
2315                                 return false;
2316                         }
2317                         return true;
2318                 } else {
2319                         # If it doesn't exist, it can't be protected
2320                         return false;
2321                 }
2322         }
2323
2324         /**
2325          * Does the title correspond to a protected article?
2326          *
2327          * @param $action String the action the page is protected from,
2328          * by default checks all actions.
2329          * @return Bool
2330          */
2331         public function isProtected( $action = '' ) {
2332                 global $wgRestrictionLevels;
2333
2334                 $restrictionTypes = $this->getRestrictionTypes();
2335
2336                 # Special pages have inherent protection
2337                 if( $this->isSpecialPage() ) {
2338                         return true;
2339                 }
2340
2341                 # Check regular protection levels
2342                 foreach ( $restrictionTypes as $type ) {
2343                         if ( $action == $type || $action == '' ) {
2344                                 $r = $this->getRestrictions( $type );
2345                                 foreach ( $wgRestrictionLevels as $level ) {
2346                                         if ( in_array( $level, $r ) && $level != '' ) {
2347                                                 return true;
2348                                         }
2349                                 }
2350                         }
2351                 }
2352
2353                 return false;
2354         }
2355
2356         /**
2357          * Determines if $user is unable to edit this page because it has been protected
2358          * by $wgNamespaceProtection.
2359          *
2360          * @param $user User object to check permissions
2361          * @return Bool
2362          */
2363         public function isNamespaceProtected( User $user ) {
2364                 global $wgNamespaceProtection;
2365
2366                 if ( isset( $wgNamespaceProtection[$this->mNamespace] ) ) {
2367                         foreach ( (array)$wgNamespaceProtection[$this->mNamespace] as $right ) {
2368                                 if ( $right != '' && !$user->isAllowed( $right ) ) {
2369                                         return true;
2370                                 }
2371                         }
2372                 }
2373                 return false;
2374         }
2375
2376         /**
2377          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
2378          *
2379          * @return Bool If the page is subject to cascading restrictions.
2380          */
2381         public function isCascadeProtected() {
2382                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
2383                 return ( $sources > 0 );
2384         }
2385
2386         /**
2387          * Cascading protection: Get the source of any cascading restrictions on this page.
2388          *
2389          * @param $getPages Bool Whether or not to retrieve the actual pages
2390          *        that the restrictions have come from.
2391          * @return Mixed Array of Title objects of the pages from which cascading restrictions
2392          *     have come, false for none, or true if such restrictions exist, but $getPages
2393          *     was not set.  The restriction array is an array of each type, each of which
2394          *     contains a array of unique groups.
2395          */
2396         public function getCascadeProtectionSources( $getPages = true ) {
2397                 global $wgContLang;
2398                 $pagerestrictions = array();
2399
2400                 if ( isset( $this->mCascadeSources ) && $getPages ) {
2401                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
2402                 } elseif ( isset( $this->mHasCascadingRestrictions ) && !$getPages ) {
2403                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
2404                 }
2405
2406                 wfProfileIn( __METHOD__ );
2407
2408                 $dbr = wfGetDB( DB_SLAVE );
2409
2410                 if ( $this->getNamespace() == NS_FILE ) {
2411                         $tables = array( 'imagelinks', 'page_restrictions' );
2412                         $where_clauses = array(
2413                                 'il_to' => $this->getDBkey(),
2414                                 'il_from=pr_page',
2415                                 'pr_cascade' => 1
2416                         );
2417                 } else {
2418                         $tables = array( 'templatelinks', 'page_restrictions' );
2419                         $where_clauses = array(
2420                                 'tl_namespace' => $this->getNamespace(),
2421                                 'tl_title' => $this->getDBkey(),
2422                                 'tl_from=pr_page',
2423                                 'pr_cascade' => 1
2424                         );
2425                 }
2426
2427                 if ( $getPages ) {
2428                         $cols = array( 'pr_page', 'page_namespace', 'page_title',
2429                                                    'pr_expiry', 'pr_type', 'pr_level' );
2430                         $where_clauses[] = 'page_id=pr_page';
2431                         $tables[] = 'page';
2432                 } else {
2433                         $cols = array( 'pr_expiry' );
2434                 }
2435
2436                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
2437
2438                 $sources = $getPages ? array() : false;
2439                 $now = wfTimestampNow();
2440                 $purgeExpired = false;
2441
2442                 foreach ( $res as $row ) {
2443                         $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2444                         if ( $expiry > $now ) {
2445                                 if ( $getPages ) {
2446                                         $page_id = $row->pr_page;
2447                                         $page_ns = $row->page_namespace;
2448                                         $page_title = $row->page_title;
2449                                         $sources[$page_id] = Title::makeTitle( $page_ns, $page_title );
2450                                         # Add groups needed for each restriction type if its not already there
2451                                         # Make sure this restriction type still exists
2452
2453                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
2454                                                 $pagerestrictions[$row->pr_type] = array();
2455                                         }
2456
2457                                         if ( isset( $pagerestrictions[$row->pr_type] ) &&
2458                                                  !in_array( $row->pr_level, $pagerestrictions[$row->pr_type] ) ) {
2459                                                 $pagerestrictions[$row->pr_type][] = $row->pr_level;
2460                                         }
2461                                 } else {
2462                                         $sources = true;
2463                                 }
2464                         } else {
2465                                 // Trigger lazy purge of expired restrictions from the db
2466                                 $purgeExpired = true;
2467                         }
2468                 }
2469                 if ( $purgeExpired ) {
2470                         Title::purgeExpiredRestrictions();
2471                 }
2472
2473                 if ( $getPages ) {
2474                         $this->mCascadeSources = $sources;
2475                         $this->mCascadingRestrictions = $pagerestrictions;
2476                 } else {
2477                         $this->mHasCascadingRestrictions = $sources;
2478                 }
2479
2480                 wfProfileOut( __METHOD__ );
2481                 return array( $sources, $pagerestrictions );
2482         }
2483
2484         /**
2485          * Accessor/initialisation for mRestrictions
2486          *
2487          * @param $action String action that permission needs to be checked for
2488          * @return Array of Strings the array of groups allowed to edit this article
2489          */
2490         public function getRestrictions( $action ) {
2491                 if ( !$this->mRestrictionsLoaded ) {
2492                         $this->loadRestrictions();
2493                 }
2494                 return isset( $this->mRestrictions[$action] )
2495                                 ? $this->mRestrictions[$action]
2496                                 : array();
2497         }
2498
2499         /**
2500          * Get the expiry time for the restriction against a given action
2501          *
2502          * @return String|Bool 14-char timestamp, or 'infinity' if the page is protected forever
2503          *      or not protected at all, or false if the action is not recognised.
2504          */
2505         public function getRestrictionExpiry( $action ) {
2506                 if ( !$this->mRestrictionsLoaded ) {
2507                         $this->loadRestrictions();
2508                 }
2509                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2510         }
2511
2512         /**
2513          * Returns cascading restrictions for the current article
2514          *
2515          * @return Boolean
2516          */
2517         function areRestrictionsCascading() {
2518                 if ( !$this->mRestrictionsLoaded ) {
2519                         $this->loadRestrictions();
2520                 }
2521
2522                 return $this->mCascadeRestriction;
2523         }
2524
2525         /**
2526          * Loads a string into mRestrictions array
2527          *
2528          * @param $res Resource restrictions as an SQL result.
2529          * @param $oldFashionedRestrictions String comma-separated list of page
2530          *        restrictions from page table (pre 1.10)
2531          */
2532         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
2533                 $rows = array();
2534
2535                 foreach ( $res as $row ) {
2536                         $rows[] = $row;
2537                 }
2538
2539                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
2540         }
2541
2542         /**
2543          * Compiles list of active page restrictions from both page table (pre 1.10)
2544          * and page_restrictions table for this existing page.
2545          * Public for usage by LiquidThreads.
2546          *
2547          * @param $rows array of db result objects
2548          * @param $oldFashionedRestrictions string comma-separated list of page
2549          *        restrictions from page table (pre 1.10)
2550          */
2551         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
2552                 global $wgContLang;
2553                 $dbr = wfGetDB( DB_SLAVE );
2554
2555                 $restrictionTypes = $this->getRestrictionTypes();
2556
2557                 foreach ( $restrictionTypes as $type ) {
2558                         $this->mRestrictions[$type] = array();
2559                         $this->mRestrictionsExpiry[$type] = $wgContLang->formatExpiry( '', TS_MW );
2560                 }
2561
2562                 $this->mCascadeRestriction = false;
2563
2564                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2565
2566                 if ( $oldFashionedRestrictions === null ) {
2567                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2568                                 array( 'page_id' => $this->getArticleId() ), __METHOD__ );
2569                 }
2570
2571                 if ( $oldFashionedRestrictions != '' ) {
2572
2573                         foreach ( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2574                                 $temp = explode( '=', trim( $restrict ) );
2575                                 if ( count( $temp ) == 1 ) {
2576                                         // old old format should be treated as edit/move restriction
2577                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2578                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2579                                 } else {
2580                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
2581                                 }
2582                         }
2583
2584                         $this->mOldRestrictions = true;
2585
2586                 }
2587
2588                 if ( count( $rows ) ) {
2589                         # Current system - load second to make them override.
2590                         $now = wfTimestampNow();
2591                         $purgeExpired = false;
2592
2593                         # Cycle through all the restrictions.
2594                         foreach ( $rows as $row ) {
2595
2596                                 // Don't take care of restrictions types that aren't allowed
2597                                 if ( !in_array( $row->pr_type, $restrictionTypes ) )
2598                                         continue;
2599
2600                                 // This code should be refactored, now that it's being used more generally,
2601                                 // But I don't really see any harm in leaving it in Block for now -werdna
2602                                 $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2603
2604                                 // Only apply the restrictions if they haven't expired!
2605                                 if ( !$expiry || $expiry > $now ) {
2606                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2607                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2608
2609                                         $this->mCascadeRestriction |= $row->pr_cascade;
2610                                 } else {
2611                                         // Trigger a lazy purge of expired restrictions
2612                                         $purgeExpired = true;
2613                                 }
2614                         }
2615
2616                         if ( $purgeExpired ) {
2617                                 Title::purgeExpiredRestrictions();
2618                         }
2619                 }
2620
2621                 $this->mRestrictionsLoaded = true;
2622         }
2623
2624         /**
2625          * Load restrictions from the page_restrictions table
2626          *
2627          * @param $oldFashionedRestrictions String comma-separated list of page
2628          *        restrictions from page table (pre 1.10)
2629          */
2630         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2631                 global $wgContLang;
2632                 if ( !$this->mRestrictionsLoaded ) {
2633                         if ( $this->exists() ) {
2634                                 $dbr = wfGetDB( DB_SLAVE );
2635
2636                                 $res = $dbr->select(
2637                                         'page_restrictions',
2638                                         '*',
2639                                         array( 'pr_page' => $this->getArticleId() ),
2640                                         __METHOD__
2641                                 );
2642
2643                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2644                         } else {
2645                                 $title_protection = $this->getTitleProtection();
2646
2647                                 if ( $title_protection ) {
2648                                         $now = wfTimestampNow();
2649                                         $expiry = $wgContLang->formatExpiry( $title_protection['pt_expiry'], TS_MW );
2650
2651                                         if ( !$expiry || $expiry > $now ) {
2652                                                 // Apply the restrictions
2653                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2654                                                 $this->mRestrictions['create'] = explode( ',', trim( $title_protection['pt_create_perm'] ) );
2655                                         } else { // Get rid of the old restrictions
2656                                                 Title::purgeExpiredRestrictions();
2657                                                 $this->mTitleProtection = false;
2658                                         }
2659                                 } else {
2660                                         $this->mRestrictionsExpiry['create'] = $wgContLang->formatExpiry( '', TS_MW );
2661                                 }
2662                                 $this->mRestrictionsLoaded = true;
2663                         }
2664                 }
2665         }
2666
2667         /**
2668          * Purge expired restrictions from the page_restrictions table
2669          */
2670         static function purgeExpiredRestrictions() {
2671                 $dbw = wfGetDB( DB_MASTER );
2672                 $dbw->delete(
2673                         'page_restrictions',
2674                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2675                         __METHOD__
2676                 );
2677
2678                 $dbw->delete(
2679                         'protected_titles',
2680                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2681                         __METHOD__
2682                 );
2683         }
2684
2685         /**
2686          * Does this have subpages?  (Warning, usually requires an extra DB query.)
2687          *
2688          * @return Bool
2689          */
2690         public function hasSubpages() {
2691                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
2692                         # Duh
2693                         return false;
2694                 }
2695
2696                 # We dynamically add a member variable for the purpose of this method
2697                 # alone to cache the result.  There's no point in having it hanging
2698                 # around uninitialized in every Title object; therefore we only add it
2699                 # if needed and don't declare it statically.
2700                 if ( isset( $this->mHasSubpages ) ) {
2701                         return $this->mHasSubpages;
2702                 }
2703
2704                 $subpages = $this->getSubpages( 1 );
2705                 if ( $subpages instanceof TitleArray ) {
2706                         return $this->mHasSubpages = (bool)$subpages->count();
2707                 }
2708                 return $this->mHasSubpages = false;
2709         }
2710
2711         /**
2712          * Get all subpages of this page.
2713          *
2714          * @param $limit Int maximum number of subpages to fetch; -1 for no limit
2715          * @return mixed TitleArray, or empty array if this page's namespace
2716          *  doesn't allow subpages
2717          */
2718         public function getSubpages( $limit = -1 ) {
2719                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
2720                         return array();
2721                 }
2722
2723                 $dbr = wfGetDB( DB_SLAVE );
2724                 $conds['page_namespace'] = $this->getNamespace();
2725                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
2726                 $options = array();
2727                 if ( $limit > -1 ) {
2728                         $options['LIMIT'] = $limit;
2729                 }
2730                 return $this->mSubpages = TitleArray::newFromResult(
2731                         $dbr->select( 'page',
2732                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
2733                                 $conds,
2734                                 __METHOD__,
2735                                 $options
2736                         )
2737                 );
2738         }
2739
2740         /**
2741          * Is there a version of this page in the deletion archive?
2742          *
2743          * @return Int the number of archived revisions
2744          */
2745         public function isDeleted() {
2746                 if ( $this->getNamespace() < 0 ) {
2747                         $n = 0;
2748                 } else {
2749                         $dbr = wfGetDB( DB_SLAVE );
2750
2751                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2752                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2753                                 __METHOD__
2754                         );
2755                         if ( $this->getNamespace() == NS_FILE ) {
2756                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2757                                         array( 'fa_name' => $this->getDBkey() ),
2758                                         __METHOD__
2759                                 );
2760                         }
2761                 }
2762                 return (int)$n;
2763         }
2764
2765         /**
2766          * Is there a version of this page in the deletion archive?
2767          *
2768          * @return Boolean
2769          */
2770         public function isDeletedQuick() {
2771                 if ( $this->getNamespace() < 0 ) {
2772                         return false;
2773                 }
2774                 $dbr = wfGetDB( DB_SLAVE );
2775                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2776                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2777                         __METHOD__
2778                 );
2779                 if ( !$deleted && $this->getNamespace() == NS_FILE ) {
2780                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2781                                 array( 'fa_name' => $this->getDBkey() ),
2782                                 __METHOD__
2783                         );
2784                 }
2785                 return $deleted;
2786         }
2787
2788         /**
2789          * Get the number of views of this page
2790          *
2791          * @return int The view count for the page
2792          */
2793         public function getCount() {
2794                 if ( $this->mCounter == -1 ) {
2795                         if ( $this->exists() ) {
2796                                 $dbr = wfGetDB( DB_SLAVE );
2797                                 $this->mCounter = $dbr->selectField( 'page',
2798                                         'page_counter',
2799                                         array( 'page_id' => $this->getArticleID() ),
2800                                         __METHOD__
2801                                 );
2802                         } else {
2803                                 $this->mCounter = 0;
2804                         }
2805                 }
2806
2807                 return $this->mCounter;
2808         }
2809
2810         /**
2811          * Get the article ID for this Title from the link cache,
2812          * adding it if necessary
2813          *
2814          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select
2815          *  for update
2816          * @return Int the ID
2817          */
2818         public function getArticleID( $flags = 0 ) {
2819                 if ( $this->getNamespace() < 0 ) {
2820                         return $this->mArticleID = 0;
2821                 }
2822                 $linkCache = LinkCache::singleton();
2823                 if ( $flags & self::GAID_FOR_UPDATE ) {
2824                         $oldUpdate = $linkCache->forUpdate( true );
2825                         $linkCache->clearLink( $this );
2826                         $this->mArticleID = $linkCache->addLinkObj( $this );
2827                         $linkCache->forUpdate( $oldUpdate );
2828                 } else {
2829                         if ( -1 == $this->mArticleID ) {
2830                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2831                         }
2832                 }
2833                 return $this->mArticleID;
2834         }
2835
2836         /**
2837          * Is this an article that is a redirect page?
2838          * Uses link cache, adding it if necessary
2839          *
2840          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2841          * @return Bool
2842          */
2843         public function isRedirect( $flags = 0 ) {
2844                 if ( !is_null( $this->mRedirect ) ) {
2845                         return $this->mRedirect;
2846                 }
2847                 # Calling getArticleID() loads the field from cache as needed
2848                 if ( !$this->getArticleID( $flags ) ) {
2849                         return $this->mRedirect = false;
2850                 }
2851                 $linkCache = LinkCache::singleton();
2852                 $this->mRedirect = (bool)$linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2853
2854                 return $this->mRedirect;
2855         }
2856
2857         /**
2858          * What is the length of this page?
2859          * Uses link cache, adding it if necessary
2860          *
2861          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2862          * @return Int
2863          */
2864         public function getLength( $flags = 0 ) {
2865                 if ( $this->mLength != -1 ) {
2866                         return $this->mLength;
2867                 }
2868                 # Calling getArticleID() loads the field from cache as needed
2869                 if ( !$this->getArticleID( $flags ) ) {
2870                         return $this->mLength = 0;
2871                 }
2872                 $linkCache = LinkCache::singleton();
2873                 $this->mLength = intval( $linkCache->getGoodLinkFieldObj( $this, 'length' ) );
2874
2875                 return $this->mLength;
2876         }
2877
2878         /**
2879          * What is the page_latest field for this page?
2880          *
2881          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2882          * @return Int or 0 if the page doesn't exist
2883          */
2884         public function getLatestRevID( $flags = 0 ) {
2885                 if ( $this->mLatestID !== false ) {
2886                         return intval( $this->mLatestID );
2887                 }
2888                 # Calling getArticleID() loads the field from cache as needed
2889                 if ( !$this->getArticleID( $flags ) ) {
2890                         return $this->mLatestID = 0;
2891                 }
2892                 $linkCache = LinkCache::singleton();
2893                 $this->mLatestID = intval( $linkCache->getGoodLinkFieldObj( $this, 'revision' ) );
2894
2895                 return $this->mLatestID;
2896         }
2897
2898         /**
2899          * This clears some fields in this object, and clears any associated
2900          * keys in the "bad links" section of the link cache.
2901          *
2902          * - This is called from Article::doEdit() and Article::insertOn() to allow
2903          * loading of the new page_id. It's also called from
2904          * Article::doDeleteArticle()
2905          *
2906          * @param $newid Int the new Article ID
2907          */
2908         public function resetArticleID( $newid ) {
2909                 $linkCache = LinkCache::singleton();
2910                 $linkCache->clearLink( $this );
2911
2912                 if ( $newid === false ) {
2913                         $this->mArticleID = -1;
2914                 } else {
2915                         $this->mArticleID = intval( $newid );
2916                 }
2917                 $this->mRestrictionsLoaded = false;
2918                 $this->mRestrictions = array();
2919                 $this->mRedirect = null;
2920                 $this->mLength = -1;
2921                 $this->mLatestID = false;
2922                 $this->mCounter = -1;
2923         }
2924
2925         /**
2926          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
2927          *
2928          * @param $text String containing title to capitalize
2929          * @param $ns int namespace index, defaults to NS_MAIN
2930          * @return String containing capitalized title
2931          */
2932         public static function capitalize( $text, $ns = NS_MAIN ) {
2933                 global $wgContLang;
2934
2935                 if ( MWNamespace::isCapitalized( $ns ) ) {
2936                         return $wgContLang->ucfirst( $text );
2937                 } else {
2938                         return $text;
2939                 }
2940         }
2941
2942         /**
2943          * Secure and split - main initialisation function for this object
2944          *
2945          * Assumes that mDbkeyform has been set, and is urldecoded
2946          * and uses underscores, but not otherwise munged.  This function
2947          * removes illegal characters, splits off the interwiki and
2948          * namespace prefixes, sets the other forms, and canonicalizes
2949          * everything.
2950          *
2951          * @return Bool true on success
2952          */
2953         private function secureAndSplit() {
2954                 global $wgContLang, $wgLocalInterwiki;
2955
2956                 # Initialisation
2957                 $this->mInterwiki = $this->mFragment = '';
2958                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2959
2960                 $dbkey = $this->mDbkeyform;
2961
2962                 # Strip Unicode bidi override characters.
2963                 # Sometimes they slip into cut-n-pasted page titles, where the
2964                 # override chars get included in list displays.
2965                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
2966
2967                 # Clean up whitespace
2968                 # Note: use of the /u option on preg_replace here will cause
2969                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
2970                 # conveniently disabling them.
2971                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
2972                 $dbkey = trim( $dbkey, '_' );
2973
2974                 if ( $dbkey == '' ) {
2975                         return false;
2976                 }
2977
2978                 if ( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2979                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2980                         return false;
2981                 }
2982
2983                 $this->mDbkeyform = $dbkey;
2984
2985                 # Initial colon indicates main namespace rather than specified default
2986                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
2987                 if ( ':' == $dbkey[0] ) {
2988                         $this->mNamespace = NS_MAIN;
2989                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
2990                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
2991                 }
2992
2993                 # Namespace or interwiki prefix
2994                 $firstPass = true;
2995                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
2996                 do {
2997                         $m = array();
2998                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
2999                                 $p = $m[1];
3000                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
3001                                         # Ordinary namespace
3002                                         $dbkey = $m[2];
3003                                         $this->mNamespace = $ns;
3004                                         # For Talk:X pages, check if X has a "namespace" prefix
3005                                         if ( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
3006                                                 if ( $wgContLang->getNsIndex( $x[1] ) ) {
3007                                                         # Disallow Talk:File:x type titles...
3008                                                         return false;
3009                                                 } elseif ( Interwiki::isValidInterwiki( $x[1] ) ) {
3010                                                         # Disallow Talk:Interwiki:x type titles...
3011                                                         return false;
3012                                                 }
3013                                         }
3014                                 } elseif ( Interwiki::isValidInterwiki( $p ) ) {
3015                                         if ( !$firstPass ) {
3016                                                 # Can't make a local interwiki link to an interwiki link.
3017                                                 # That's just crazy!
3018                                                 return false;
3019                                         }
3020
3021                                         # Interwiki link
3022                                         $dbkey = $m[2];
3023                                         $this->mInterwiki = $wgContLang->lc( $p );
3024
3025                                         # Redundant interwiki prefix to the local wiki
3026                                         if ( $wgLocalInterwiki !== false
3027                                                 && 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) )
3028                                         {
3029                                                 if ( $dbkey == '' ) {
3030                                                         # Can't have an empty self-link
3031                                                         return false;
3032                                                 }
3033                                                 $this->mInterwiki = '';
3034                                                 $firstPass = false;
3035                                                 # Do another namespace split...
3036                                                 continue;
3037                                         }
3038
3039                                         # If there's an initial colon after the interwiki, that also
3040                                         # resets the default namespace
3041                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
3042                                                 $this->mNamespace = NS_MAIN;
3043                                                 $dbkey = substr( $dbkey, 1 );
3044                                         }
3045                                 }
3046                                 # If there's no recognized interwiki or namespace,
3047                                 # then let the colon expression be part of the title.
3048                         }
3049                         break;
3050                 } while ( true );
3051
3052                 # We already know that some pages won't be in the database!
3053                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
3054                         $this->mArticleID = 0;
3055                 }
3056                 $fragment = strstr( $dbkey, '#' );
3057                 if ( false !== $fragment ) {
3058                         $this->setFragment( $fragment );
3059                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
3060                         # remove whitespace again: prevents "Foo_bar_#"
3061                         # becoming "Foo_bar_"
3062                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
3063                 }
3064
3065                 # Reject illegal characters.
3066                 $rxTc = self::getTitleInvalidRegex();
3067                 if ( preg_match( $rxTc, $dbkey ) ) {
3068                         return false;
3069                 }
3070
3071                 # Pages with "/./" or "/../" appearing in the URLs will often be un-
3072                 # reachable due to the way web browsers deal with 'relative' URLs.
3073                 # Also, they conflict with subpage syntax.  Forbid them explicitly.
3074                 if ( strpos( $dbkey, '.' ) !== false &&
3075                          ( $dbkey === '.' || $dbkey === '..' ||
3076                            strpos( $dbkey, './' ) === 0  ||
3077                            strpos( $dbkey, '../' ) === 0 ||
3078                            strpos( $dbkey, '/./' ) !== false ||
3079                            strpos( $dbkey, '/../' ) !== false  ||
3080                            substr( $dbkey, -2 ) == '/.' ||
3081                            substr( $dbkey, -3 ) == '/..' ) )
3082                 {
3083                         return false;
3084                 }
3085
3086                 # Magic tilde sequences? Nu-uh!
3087                 if ( strpos( $dbkey, '~~~' ) !== false ) {
3088                         return false;
3089                 }
3090
3091                 # Limit the size of titles to 255 bytes. This is typically the size of the
3092                 # underlying database field. We make an exception for special pages, which
3093                 # don't need to be stored in the database, and may edge over 255 bytes due
3094                 # to subpage syntax for long titles, e.g. [[Special:Block/Long name]]
3095                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
3096                   strlen( $dbkey ) > 512 )
3097                 {
3098                         return false;
3099                 }
3100
3101                 # Normally, all wiki links are forced to have an initial capital letter so [[foo]]
3102                 # and [[Foo]] point to the same place.  Don't force it for interwikis, since the
3103                 # other site might be case-sensitive.
3104                 $this->mUserCaseDBKey = $dbkey;
3105                 if ( $this->mInterwiki == '' ) {
3106                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
3107                 }
3108
3109                 # Can't make a link to a namespace alone... "empty" local links can only be
3110                 # self-links with a fragment identifier.
3111                 if ( $dbkey == '' && $this->mInterwiki == '' && $this->mNamespace != NS_MAIN ) {
3112                         return false;
3113                 }
3114
3115                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
3116                 // IP names are not allowed for accounts, and can only be referring to
3117                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
3118                 // there are numerous ways to present the same IP. Having sp:contribs scan
3119                 // them all is silly and having some show the edits and others not is
3120                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
3121                 $dbkey = ( $this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK )
3122                         ? IP::sanitizeIP( $dbkey )
3123                         : $dbkey;
3124
3125                 // Any remaining initial :s are illegal.
3126                 if ( $dbkey !== '' && ':' == $dbkey[0] ) {
3127                         return false;
3128                 }
3129
3130                 # Fill fields
3131                 $this->mDbkeyform = $dbkey;
3132                 $this->mUrlform = wfUrlencode( $dbkey );
3133
3134                 $this->mTextform = str_replace( '_', ' ', $dbkey );
3135
3136                 return true;
3137         }
3138
3139         /**
3140          * Get an array of Title objects linking to this Title
3141          * Also stores the IDs in the link cache.
3142          *
3143          * WARNING: do not use this function on arbitrary user-supplied titles!
3144          * On heavily-used templates it will max out the memory.
3145          *
3146          * @param $options Array: may be FOR UPDATE
3147          * @param $table String: table name
3148          * @param $prefix String: fields prefix
3149          * @return Array of Title objects linking here
3150          */
3151         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3152                 $linkCache = LinkCache::singleton();
3153
3154                 if ( count( $options ) > 0 ) {
3155                         $db = wfGetDB( DB_MASTER );
3156                 } else {
3157                         $db = wfGetDB( DB_SLAVE );
3158                 }
3159
3160                 $res = $db->select(
3161                         array( 'page', $table ),
3162                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ),
3163                         array(
3164                                 "{$prefix}_from=page_id",
3165                                 "{$prefix}_namespace" => $this->getNamespace(),
3166                                 "{$prefix}_title"     => $this->getDBkey() ),
3167                         __METHOD__,
3168                         $options
3169                 );
3170
3171                 $retVal = array();
3172                 if ( $db->numRows( $res ) ) {
3173                         foreach ( $res as $row ) {
3174                                 $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title );
3175                                 if ( $titleObj ) {
3176                                         $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3177                                         $retVal[] = $titleObj;
3178                                 }
3179                         }
3180                 }
3181                 return $retVal;
3182         }
3183
3184         /**
3185          * Get an array of Title objects using this Title as a template
3186          * Also stores the IDs in the link cache.
3187          *
3188          * WARNING: do not use this function on arbitrary user-supplied titles!
3189          * On heavily-used templates it will max out the memory.
3190          *
3191          * @param $options Array: may be FOR UPDATE
3192          * @return Array of Title the Title objects linking here
3193          */
3194         public function getTemplateLinksTo( $options = array() ) {
3195                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
3196         }
3197
3198         /**
3199          * Get an array of Title objects referring to non-existent articles linked from this page
3200          *
3201          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
3202          * @return Array of Title the Title objects
3203          */
3204         public function getBrokenLinksFrom() {
3205                 if ( $this->getArticleId() == 0 ) {
3206                         # All links from article ID 0 are false positives
3207                         return array();
3208                 }
3209
3210                 $dbr = wfGetDB( DB_SLAVE );
3211                 $res = $dbr->select(
3212                         array( 'page', 'pagelinks' ),
3213                         array( 'pl_namespace', 'pl_title' ),
3214                         array(
3215                                 'pl_from' => $this->getArticleId(),
3216                                 'page_namespace IS NULL'
3217                         ),
3218                         __METHOD__, array(),
3219                         array(
3220                                 'page' => array(
3221                                         'LEFT JOIN',
3222                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
3223                                 )
3224                         )
3225                 );
3226
3227                 $retVal = array();
3228                 foreach ( $res as $row ) {
3229                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
3230                 }
3231                 return $retVal;
3232         }
3233
3234
3235         /**
3236          * Get a list of URLs to purge from the Squid cache when this
3237          * page changes
3238          *
3239          * @return Array of String the URLs
3240          */
3241         public function getSquidURLs() {
3242                 global $wgContLang;
3243
3244                 $urls = array(
3245                         $this->getInternalURL(),
3246                         $this->getInternalURL( 'action=history' )
3247                 );
3248
3249                 // purge variant urls as well
3250                 if ( $wgContLang->hasVariants() ) {
3251                         $variants = $wgContLang->getVariants();
3252                         foreach ( $variants as $vCode ) {
3253                                 $urls[] = $this->getInternalURL( '', $vCode );
3254                         }
3255                 }
3256
3257                 return $urls;
3258         }
3259
3260         /**
3261          * Purge all applicable Squid URLs
3262          */
3263         public function purgeSquid() {
3264                 global $wgUseSquid;
3265                 if ( $wgUseSquid ) {
3266                         $urls = $this->getSquidURLs();
3267                         $u = new SquidUpdate( $urls );
3268                         $u->doUpdate();
3269                 }
3270         }
3271
3272         /**
3273          * Move this page without authentication
3274          *
3275          * @param $nt Title the new page Title
3276          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3277          */
3278         public function moveNoAuth( &$nt ) {
3279                 return $this->moveTo( $nt, false );
3280         }
3281
3282         /**
3283          * Check whether a given move operation would be valid.
3284          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
3285          *
3286          * @param $nt Title the new title
3287          * @param $auth Bool indicates whether $wgUser's permissions
3288          *  should be checked
3289          * @param $reason String is the log summary of the move, used for spam checking
3290          * @return Mixed True on success, getUserPermissionsErrors()-like array on failure
3291          */
3292         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
3293                 global $wgUser;
3294
3295                 $errors = array();
3296                 if ( !$nt ) {
3297                         // Normally we'd add this to $errors, but we'll get
3298                         // lots of syntax errors if $nt is not an object
3299                         return array( array( 'badtitletext' ) );
3300                 }
3301                 if ( $this->equals( $nt ) ) {
3302                         $errors[] = array( 'selfmove' );
3303                 }
3304                 if ( !$this->isMovable() ) {
3305                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
3306                 }
3307                 if ( $nt->getInterwiki() != '' ) {
3308                         $errors[] = array( 'immobile-target-namespace-iw' );
3309                 }
3310                 if ( !$nt->isMovable() ) {
3311                         $errors[] = array( 'immobile-target-namespace', $nt->getNsText() );
3312                 }
3313
3314                 $oldid = $this->getArticleID();
3315                 $newid = $nt->getArticleID();
3316
3317                 if ( strlen( $nt->getDBkey() ) < 1 ) {
3318                         $errors[] = array( 'articleexists' );
3319                 }
3320                 if ( ( $this->getDBkey() == '' ) ||
3321                          ( !$oldid ) ||
3322                          ( $nt->getDBkey() == '' ) ) {
3323                         $errors[] = array( 'badarticleerror' );
3324                 }
3325
3326                 // Image-specific checks
3327                 if ( $this->getNamespace() == NS_FILE ) {
3328                         $errors = array_merge( $errors, $this->validateFileMoveOperation( $nt ) );
3329                 }
3330
3331                 if ( $nt->getNamespace() == NS_FILE && $this->getNamespace() != NS_FILE ) {
3332                         $errors[] = array( 'nonfile-cannot-move-to-file' );
3333                 }
3334
3335                 if ( $auth ) {
3336                         $errors = wfMergeErrorArrays( $errors,
3337                                 $this->getUserPermissionsErrors( 'move', $wgUser ),
3338                                 $this->getUserPermissionsErrors( 'edit', $wgUser ),
3339                                 $nt->getUserPermissionsErrors( 'move-target', $wgUser ),
3340                                 $nt->getUserPermissionsErrors( 'edit', $wgUser ) );
3341                 }
3342
3343                 $match = EditPage::matchSummarySpamRegex( $reason );
3344                 if ( $match !== false ) {
3345                         // This is kind of lame, won't display nice
3346                         $errors[] = array( 'spamprotectiontext' );
3347                 }
3348
3349                 $err = null;
3350                 if ( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
3351                         $errors[] = array( 'hookaborted', $err );
3352                 }
3353
3354                 # The move is allowed only if (1) the target doesn't exist, or
3355                 # (2) the target is a redirect to the source, and has no history
3356                 # (so we can undo bad moves right after they're done).
3357
3358                 if ( 0 != $newid ) { # Target exists; check for validity
3359                         if ( !$this->isValidMoveTarget( $nt ) ) {
3360                                 $errors[] = array( 'articleexists' );
3361                         }
3362                 } else {
3363                         $tp = $nt->getTitleProtection();
3364                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
3365                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
3366                                 $errors[] = array( 'cantmove-titleprotected' );
3367                         }
3368                 }
3369                 if ( empty( $errors ) ) {
3370                         return true;
3371                 }
3372                 return $errors;
3373         }
3374
3375         /**
3376          * Check if the requested move target is a valid file move target
3377          * @param Title $nt Target title
3378          * @return array List of errors
3379          */
3380         protected function validateFileMoveOperation( $nt ) {
3381                 global $wgUser;
3382
3383                 $errors = array();
3384
3385                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is not allowed until below
3386
3387                 $file = wfLocalFile( $this );
3388                 if ( $file->exists() ) {
3389                         if ( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
3390                                 $errors[] = array( 'imageinvalidfilename' );
3391                         }
3392                         if ( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
3393                                 $errors[] = array( 'imagetypemismatch' );
3394                         }
3395                 }
3396
3397                 if ( $nt->getNamespace() != NS_FILE ) {
3398                         $errors[] = array( 'imagenocrossnamespace' );
3399                         // From here we want to do checks on a file object, so if we can't
3400                         // create one, we must return.
3401                         return $errors;
3402                 }
3403
3404                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is allowed below here
3405
3406                 $destFile = wfLocalFile( $nt );
3407                 if ( !$wgUser->isAllowed( 'reupload-shared' ) && !$destFile->exists() && wfFindFile( $nt ) ) {
3408                         $errors[] = array( 'file-exists-sharedrepo' );
3409                 }
3410
3411                 return $errors;
3412         }
3413
3414         /**
3415          * Move a title to a new location
3416          *
3417          * @param $nt Title the new title
3418          * @param $auth Bool indicates whether $wgUser's permissions
3419          *  should be checked
3420          * @param $reason String the reason for the move
3421          * @param $createRedirect Bool Whether to create a redirect from the old title to the new title.
3422          *  Ignored if the user doesn't have the suppressredirect right.
3423          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3424          */
3425         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
3426                 global $wgUser;
3427                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
3428                 if ( is_array( $err ) ) {
3429                         // Auto-block user's IP if the account was "hard" blocked
3430                         $wgUser->spreadAnyEditBlock();
3431                         return $err;
3432                 }
3433
3434                 // If it is a file, move it first.
3435                 // It is done before all other moving stuff is done because it's hard to revert.
3436                 $dbw = wfGetDB( DB_MASTER );
3437                 if ( $this->getNamespace() == NS_FILE ) {
3438                         $file = wfLocalFile( $this );
3439                         if ( $file->exists() ) {
3440                                 $status = $file->move( $nt );
3441                                 if ( !$status->isOk() ) {
3442                                         return $status->getErrorsArray();
3443                                 }
3444                         }
3445                 }
3446                 // Clear RepoGroup process cache
3447                 RepoGroup::singleton()->clearCache( $this );
3448                 RepoGroup::singleton()->clearCache( $nt ); # clear false negative cache
3449
3450                 $dbw->begin(); # If $file was a LocalFile, its transaction would have closed our own.
3451                 $pageid = $this->getArticleID( self::GAID_FOR_UPDATE );
3452                 $protected = $this->isProtected();
3453                 $pageCountChange = ( $createRedirect ? 1 : 0 ) - ( $nt->exists() ? 1 : 0 );
3454
3455                 // Do the actual move
3456                 $err = $this->moveToInternal( $nt, $reason, $createRedirect );
3457                 if ( is_array( $err ) ) {
3458                         # @todo FIXME: What about the File we have already moved?
3459                         $dbw->rollback();
3460                         return $err;
3461                 }
3462
3463                 $redirid = $this->getArticleID();
3464
3465                 // Refresh the sortkey for this row.  Be careful to avoid resetting
3466                 // cl_timestamp, which may disturb time-based lists on some sites.
3467                 $prefixes = $dbw->select(
3468                         'categorylinks',
3469                         array( 'cl_sortkey_prefix', 'cl_to' ),
3470                         array( 'cl_from' => $pageid ),
3471                         __METHOD__
3472                 );
3473                 foreach ( $prefixes as $prefixRow ) {
3474                         $prefix = $prefixRow->cl_sortkey_prefix;
3475                         $catTo = $prefixRow->cl_to;
3476                         $dbw->update( 'categorylinks',
3477                                 array(
3478                                         'cl_sortkey' => Collation::singleton()->getSortKey(
3479                                                 $nt->getCategorySortkey( $prefix ) ),
3480                                         'cl_timestamp=cl_timestamp' ),
3481                                 array(
3482                                         'cl_from' => $pageid,
3483                                         'cl_to' => $catTo ),
3484                                 __METHOD__
3485                         );
3486                 }
3487
3488                 if ( $protected ) {
3489                         # Protect the redirect title as the title used to be...
3490                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
3491                                 array(
3492                                         'pr_page'    => $redirid,
3493                                         'pr_type'    => 'pr_type',
3494                                         'pr_level'   => 'pr_level',
3495                                         'pr_cascade' => 'pr_cascade',
3496                                         'pr_user'    => 'pr_user',
3497                                         'pr_expiry'  => 'pr_expiry'
3498                                 ),
3499                                 array( 'pr_page' => $pageid ),
3500                                 __METHOD__,
3501                                 array( 'IGNORE' )
3502                         );
3503                         # Update the protection log
3504                         $log = new LogPage( 'protect' );
3505                         $comment = wfMsgForContent( 'prot_1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
3506                         if ( $reason ) {
3507                                 $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3508                         }
3509                         // @todo FIXME: $params?
3510                         $log->addEntry( 'move_prot', $nt, $comment, array( $this->getPrefixedText() ) );
3511                 }
3512
3513                 # Update watchlists
3514                 $oldnamespace = $this->getNamespace() & ~1;
3515                 $newnamespace = $nt->getNamespace() & ~1;
3516                 $oldtitle = $this->getDBkey();
3517                 $newtitle = $nt->getDBkey();
3518
3519                 if ( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
3520                         WatchedItem::duplicateEntries( $this, $nt );
3521                 }
3522
3523                 # Update search engine
3524                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
3525                 $u->doUpdate();
3526                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
3527                 $u->doUpdate();
3528
3529                 $dbw->commit();
3530
3531                 # Update site_stats
3532                 if ( $this->isContentPage() && !$nt->isContentPage() ) {
3533                         # No longer a content page
3534                         # Not viewed, edited, removing
3535                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange );
3536                 } elseif ( !$this->isContentPage() && $nt->isContentPage() ) {
3537                         # Now a content page
3538                         # Not viewed, edited, adding
3539                         $u = new SiteStatsUpdate( 0, 1, + 1, $pageCountChange );
3540                 } elseif ( $pageCountChange ) {
3541                         # Redirect added
3542                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
3543                 } else {
3544                         # Nothing special
3545                         $u = false;
3546                 }
3547                 if ( $u ) {
3548                         $u->doUpdate();
3549                 }
3550
3551                 # Update message cache for interface messages
3552                 if ( $this->getNamespace() == NS_MEDIAWIKI ) {
3553                         # @bug 17860: old article can be deleted, if this the case,
3554                         # delete it from message cache
3555                         if ( $this->getArticleID() === 0 ) {
3556                                 MessageCache::singleton()->replace( $this->getDBkey(), false );
3557                         } else {
3558                                 $rev = Revision::newFromTitle( $this );
3559                                 MessageCache::singleton()->replace( $this->getDBkey(), $rev->getText() );
3560                         }
3561                 }
3562                 if ( $nt->getNamespace() == NS_MEDIAWIKI ) {
3563                         $rev = Revision::newFromTitle( $nt );
3564                         MessageCache::singleton()->replace( $nt->getDBkey(), $rev->getText() );
3565                 }
3566
3567                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3568                 return true;
3569         }
3570
3571         /**
3572          * Move page to a title which is either a redirect to the
3573          * source page or nonexistent
3574          *
3575          * @param $nt Title the page to move to, which should be a redirect or nonexistent
3576          * @param $reason String The reason for the move
3577          * @param $createRedirect Bool Whether to leave a redirect at the old title.  Ignored
3578          *   if the user doesn't have the suppressredirect right
3579          */
3580         private function moveToInternal( &$nt, $reason = '', $createRedirect = true ) {
3581                 global $wgUser, $wgContLang;
3582
3583                 if ( $nt->exists() ) {
3584                         $moveOverRedirect = true;
3585                         $logType = 'move_redir';
3586                 } else {
3587                         $moveOverRedirect = false;
3588                         $logType = 'move';
3589                 }
3590
3591                 $redirectSuppressed = !$createRedirect && $wgUser->isAllowed( 'suppressredirect' );
3592
3593                 $logEntry = new ManualLogEntry( 'move', $logType );
3594                 $logEntry->setPerformer( $wgUser );
3595                 $logEntry->setTarget( $this );
3596                 $logEntry->setComment( $reason );
3597                 $logEntry->setParameters( array(
3598                         '4::target' => $nt->getPrefixedText(),
3599                         '5::noredir' => $redirectSuppressed ? '1': '0',
3600                 ) );
3601
3602                 $formatter = LogFormatter::newFromEntry( $logEntry );
3603                 $formatter->setContext( RequestContext::newExtraneousContext( $this ) );
3604                 $comment = $formatter->getPlainActionText();
3605                 if ( $reason ) {
3606                         $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3607                 }
3608                 # Truncate for whole multibyte characters.
3609                 $comment = $wgContLang->truncate( $comment, 255 );
3610
3611                 $oldid = $this->getArticleID();
3612                 $latest = $this->getLatestRevID();
3613
3614                 $dbw = wfGetDB( DB_MASTER );
3615
3616                 if ( $moveOverRedirect ) {
3617                         $rcts = $dbw->timestamp( $nt->getEarliestRevTime() );
3618
3619                         $newid = $nt->getArticleID();
3620                         $newns = $nt->getNamespace();
3621                         $newdbk = $nt->getDBkey();
3622
3623                         # Delete the old redirect. We don't save it to history since
3624                         # by definition if we've got here it's rather uninteresting.
3625                         # We have to remove it so that the next step doesn't trigger
3626                         # a conflict on the unique namespace+title index...
3627                         $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3628                         if ( !$dbw->cascadingDeletes() ) {
3629                                 $dbw->delete( 'revision', array( 'rev_page' => $newid ), __METHOD__ );
3630
3631                                 $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
3632                                 $dbw->delete( 'imagelinks', array( 'il_from' => $newid ), __METHOD__ );
3633                                 $dbw->delete( 'categorylinks', array( 'cl_from' => $newid ), __METHOD__ );
3634                                 $dbw->delete( 'templatelinks', array( 'tl_from' => $newid ), __METHOD__ );
3635                                 $dbw->delete( 'externallinks', array( 'el_from' => $newid ), __METHOD__ );
3636                                 $dbw->delete( 'langlinks', array( 'll_from' => $newid ), __METHOD__ );
3637                                 $dbw->delete( 'iwlinks', array( 'iwl_from' => $newid ), __METHOD__ );
3638                                 $dbw->delete( 'redirect', array( 'rd_from' => $newid ), __METHOD__ );
3639                                 $dbw->delete( 'page_props', array( 'pp_page' => $newid ), __METHOD__ );
3640                         }
3641                         // If the target page was recently created, it may have an entry in recentchanges still
3642                         $dbw->delete( 'recentchanges',
3643                                 array( 'rc_timestamp' => $rcts, 'rc_namespace' => $newns, 'rc_title' => $newdbk, 'rc_new' => 1 ),
3644                                 __METHOD__
3645                         );
3646                 }
3647
3648                 # Save a null revision in the page's history notifying of the move
3649                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3650                 if ( !is_object( $nullRevision ) ) {
3651                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3652                 }
3653                 $nullRevId = $nullRevision->insertOn( $dbw );
3654
3655                 $now = wfTimestampNow();
3656                 # Change the name of the target page:
3657                 $dbw->update( 'page',
3658                         /* SET */ array(
3659                                 'page_touched'   => $dbw->timestamp( $now ),
3660                                 'page_namespace' => $nt->getNamespace(),
3661                                 'page_title'     => $nt->getDBkey(),
3662                                 'page_latest'    => $nullRevId,
3663                         ),
3664                         /* WHERE */ array( 'page_id' => $oldid ),
3665                         __METHOD__
3666                 );
3667                 $nt->resetArticleID( $oldid );
3668
3669                 $article = WikiPage::factory( $nt );
3670                 wfRunHooks( 'NewRevisionFromEditComplete',
3671                         array( $article, $nullRevision, $latest, $wgUser ) );
3672                 $article->setCachedLastEditTime( $now );
3673
3674                 # Recreate the redirect, this time in the other direction.
3675                 if ( $createRedirect || !$wgUser->isAllowed( 'suppressredirect' ) ) {
3676                         $mwRedir = MagicWord::get( 'redirect' );
3677                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3678                         $redirectArticle = WikiPage::factory( $this );
3679                         $newid = $redirectArticle->insertOn( $dbw );
3680                         if ( $newid ) { // sanity
3681                                 $redirectRevision = new Revision( array(
3682                                         'page'    => $newid,
3683                                         'comment' => $comment,
3684                                         'text'    => $redirectText ) );
3685                                 $redirectRevision->insertOn( $dbw );
3686                                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3687
3688                                 wfRunHooks( 'NewRevisionFromEditComplete',
3689                                         array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3690
3691                                 # Now, we record the link from the redirect to the new title.
3692                                 # It should have no other outgoing links...
3693                                 $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
3694                                 $dbw->insert( 'pagelinks',
3695                                         array(
3696                                                 'pl_from'      => $newid,
3697                                                 'pl_namespace' => $nt->getNamespace(),
3698                                                 'pl_title'     => $nt->getDBkey() ),
3699                                         __METHOD__ );
3700                         }
3701                 } else {
3702                         $this->resetArticleID( 0 );
3703                 }
3704
3705                 # Log the move
3706                 $logid = $logEntry->insert();
3707                 $logEntry->publish( $logid );
3708
3709                 # Purge caches for old and new titles
3710                 if ( $moveOverRedirect ) {
3711                         # A simple purge is enough when moving over a redirect
3712                         $nt->purgeSquid();
3713                 } else {
3714                         # Purge caches as per article creation, including any pages that link to this title
3715                         Article::onArticleCreate( $nt );
3716                 }
3717                 $this->purgeSquid();
3718         }
3719
3720         /**
3721          * Move this page's subpages to be subpages of $nt
3722          *
3723          * @param $nt Title Move target
3724          * @param $auth bool Whether $wgUser's permissions should be checked
3725          * @param $reason string The reason for the move
3726          * @param $createRedirect bool Whether to create redirects from the old subpages to
3727          *     the new ones Ignored if the user doesn't have the 'suppressredirect' right
3728          * @return mixed array with old page titles as keys, and strings (new page titles) or
3729          *     arrays (errors) as values, or an error array with numeric indices if no pages
3730          *     were moved
3731          */
3732         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3733                 global $wgMaximumMovedPages;
3734                 // Check permissions
3735                 if ( !$this->userCan( 'move-subpages' ) ) {
3736                         return array( 'cant-move-subpages' );
3737                 }
3738                 // Do the source and target namespaces support subpages?
3739                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
3740                         return array( 'namespace-nosubpages',
3741                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3742                 }
3743                 if ( !MWNamespace::hasSubpages( $nt->getNamespace() ) ) {
3744                         return array( 'namespace-nosubpages',
3745                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3746                 }
3747
3748                 $subpages = $this->getSubpages( $wgMaximumMovedPages + 1 );
3749                 $retval = array();
3750                 $count = 0;
3751                 foreach ( $subpages as $oldSubpage ) {
3752                         $count++;
3753                         if ( $count > $wgMaximumMovedPages ) {
3754                                 $retval[$oldSubpage->getPrefixedTitle()] =
3755                                                 array( 'movepage-max-pages',
3756                                                         $wgMaximumMovedPages );
3757                                 break;
3758                         }
3759
3760                         // We don't know whether this function was called before
3761                         // or after moving the root page, so check both
3762                         // $this and $nt
3763                         if ( $oldSubpage->getArticleId() == $this->getArticleId() ||
3764                                         $oldSubpage->getArticleID() == $nt->getArticleId() )
3765                         {
3766                                 // When moving a page to a subpage of itself,
3767                                 // don't move it twice
3768                                 continue;
3769                         }
3770                         $newPageName = preg_replace(
3771                                         '#^' . preg_quote( $this->getDBkey(), '#' ) . '#',
3772                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3773                                         $oldSubpage->getDBkey() );
3774                         if ( $oldSubpage->isTalkPage() ) {
3775                                 $newNs = $nt->getTalkPage()->getNamespace();
3776                         } else {
3777                                 $newNs = $nt->getSubjectPage()->getNamespace();
3778                         }
3779                         # Bug 14385: we need makeTitleSafe because the new page names may
3780                         # be longer than 255 characters.
3781                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3782
3783                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3784                         if ( $success === true ) {
3785                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3786                         } else {
3787                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3788                         }
3789                 }
3790                 return $retval;
3791         }
3792
3793         /**
3794          * Checks if this page is just a one-rev redirect.
3795          * Adds lock, so don't use just for light purposes.
3796          *
3797          * @return Bool
3798          */
3799         public function isSingleRevRedirect() {
3800                 $dbw = wfGetDB( DB_MASTER );
3801                 # Is it a redirect?
3802                 $row = $dbw->selectRow( 'page',
3803                         array( 'page_is_redirect', 'page_latest', 'page_id' ),
3804                         $this->pageCond(),
3805                         __METHOD__,
3806                         array( 'FOR UPDATE' )
3807                 );
3808                 # Cache some fields we may want
3809                 $this->mArticleID = $row ? intval( $row->page_id ) : 0;
3810                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3811                 $this->mLatestID = $row ? intval( $row->page_latest ) : false;
3812                 if ( !$this->mRedirect ) {
3813                         return false;
3814                 }
3815                 # Does the article have a history?
3816                 $row = $dbw->selectField( array( 'page', 'revision' ),
3817                         'rev_id',
3818                         array( 'page_namespace' => $this->getNamespace(),
3819                                 'page_title' => $this->getDBkey(),
3820                                 'page_id=rev_page',
3821                                 'page_latest != rev_id'
3822                         ),
3823                         __METHOD__,
3824                         array( 'FOR UPDATE' )
3825                 );
3826                 # Return true if there was no history
3827                 return ( $row === false );
3828         }
3829
3830         /**
3831          * Checks if $this can be moved to a given Title
3832          * - Selects for update, so don't call it unless you mean business
3833          *
3834          * @param $nt Title the new title to check
3835          * @return Bool
3836          */
3837         public function isValidMoveTarget( $nt ) {
3838                 # Is it an existing file?
3839                 if ( $nt->getNamespace() == NS_FILE ) {
3840                         $file = wfLocalFile( $nt );
3841                         if ( $file->exists() ) {
3842                                 wfDebug( __METHOD__ . ": file exists\n" );
3843                                 return false;
3844                         }
3845                 }
3846                 # Is it a redirect with no history?
3847                 if ( !$nt->isSingleRevRedirect() ) {
3848                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3849                         return false;
3850                 }
3851                 # Get the article text
3852                 $rev = Revision::newFromTitle( $nt );
3853                 if( !is_object( $rev ) ){
3854                         return false;
3855                 }
3856                 $text = $rev->getText();
3857                 # Does the redirect point to the source?
3858                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3859                 $m = array();
3860                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
3861                         $redirTitle = Title::newFromText( $m[1] );
3862                         if ( !is_object( $redirTitle ) ||
3863                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3864                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
3865                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3866                                 return false;
3867                         }
3868                 } else {
3869                         # Fail safe
3870                         wfDebug( __METHOD__ . ": failsafe\n" );
3871                         return false;
3872                 }
3873                 return true;
3874         }
3875
3876         /**
3877          * Get categories to which this Title belongs and return an array of
3878          * categories' names.
3879          *
3880          * @return Array of parents in the form:
3881          *        $parent => $currentarticle
3882          */
3883         public function getParentCategories() {
3884                 global $wgContLang;
3885
3886                 $data = array();
3887
3888                 $titleKey = $this->getArticleId();
3889
3890                 if ( $titleKey === 0 ) {
3891                         return $data;
3892                 }
3893
3894                 $dbr = wfGetDB( DB_SLAVE );
3895
3896                 $res = $dbr->select( 'categorylinks', '*',
3897                         array(
3898                                 'cl_from' => $titleKey,
3899                         ),
3900                         __METHOD__,
3901                         array()
3902                 );
3903
3904                 if ( $dbr->numRows( $res ) > 0 ) {
3905                         foreach ( $res as $row ) {
3906                                 // $data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
3907                                 $data[$wgContLang->getNSText( NS_CATEGORY ) . ':' . $row->cl_to] = $this->getFullText();
3908                         }
3909                 }
3910                 return $data;
3911         }
3912
3913         /**
3914          * Get a tree of parent categories
3915          *
3916          * @param $children Array with the children in the keys, to check for circular refs
3917          * @return Array Tree of parent categories
3918          */
3919         public function getParentCategoryTree( $children = array() ) {
3920                 $stack = array();
3921                 $parents = $this->getParentCategories();
3922
3923                 if ( $parents ) {
3924                         foreach ( $parents as $parent => $current ) {
3925                                 if ( array_key_exists( $parent, $children ) ) {
3926                                         # Circular reference
3927                                         $stack[$parent] = array();
3928                                 } else {
3929                                         $nt = Title::newFromText( $parent );
3930                                         if ( $nt ) {
3931                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array( $parent => 1 ) );
3932                                         }
3933                                 }
3934                         }
3935                 }
3936
3937                 return $stack;
3938         }
3939
3940         /**
3941          * Get an associative array for selecting this title from
3942          * the "page" table
3943          *
3944          * @return Array suitable for the $where parameter of DB::select()
3945          */
3946         public function pageCond() {
3947                 if ( $this->mArticleID > 0 ) {
3948                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
3949                         return array( 'page_id' => $this->mArticleID );
3950                 } else {
3951                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
3952                 }
3953         }
3954
3955         /**
3956          * Get the revision ID of the previous revision
3957          *
3958          * @param $revId Int Revision ID. Get the revision that was before this one.
3959          * @param $flags Int Title::GAID_FOR_UPDATE
3960          * @return Int|Bool Old revision ID, or FALSE if none exists
3961          */
3962         public function getPreviousRevisionID( $revId, $flags = 0 ) {
3963                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3964                 return $db->selectField( 'revision', 'rev_id',
3965                         array(
3966                                 'rev_page' => $this->getArticleId( $flags ),
3967                                 'rev_id < ' . intval( $revId )
3968                         ),
3969                         __METHOD__,
3970                         array( 'ORDER BY' => 'rev_id DESC' )
3971                 );
3972         }
3973
3974         /**
3975          * Get the revision ID of the next revision
3976          *
3977          * @param $revId Int Revision ID. Get the revision that was after this one.
3978          * @param $flags Int Title::GAID_FOR_UPDATE
3979          * @return Int|Bool Next revision ID, or FALSE if none exists
3980          */
3981         public function getNextRevisionID( $revId, $flags = 0 ) {
3982                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3983                 return $db->selectField( 'revision', 'rev_id',
3984                         array(
3985                                 'rev_page' => $this->getArticleId( $flags ),
3986                                 'rev_id > ' . intval( $revId )
3987                         ),
3988                         __METHOD__,
3989                         array( 'ORDER BY' => 'rev_id' )
3990                 );
3991         }
3992
3993         /**
3994          * Get the first revision of the page
3995          *
3996          * @param $flags Int Title::GAID_FOR_UPDATE
3997          * @return Revision|Null if page doesn't exist
3998          */
3999         public function getFirstRevision( $flags = 0 ) {
4000                 $pageId = $this->getArticleId( $flags );
4001                 if ( $pageId ) {
4002                         $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4003                         $row = $db->selectRow( 'revision', '*',
4004                                 array( 'rev_page' => $pageId ),
4005                                 __METHOD__,
4006                                 array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
4007                         );
4008                         if ( $row ) {
4009                                 return new Revision( $row );
4010                         }
4011                 }
4012                 return null;
4013         }
4014
4015         /**
4016          * Get the oldest revision timestamp of this page
4017          *
4018          * @param $flags Int Title::GAID_FOR_UPDATE
4019          * @return String: MW timestamp
4020          */
4021         public function getEarliestRevTime( $flags = 0 ) {
4022                 $rev = $this->getFirstRevision( $flags );
4023                 return $rev ? $rev->getTimestamp() : null;
4024         }
4025
4026         /**
4027          * Check if this is a new page
4028          *
4029          * @return bool
4030          */
4031         public function isNewPage() {
4032                 $dbr = wfGetDB( DB_SLAVE );
4033                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
4034         }
4035
4036         /**
4037          * Get the number of revisions between the given revision.
4038          * Used for diffs and other things that really need it.
4039          *
4040          * @param $old int|Revision Old revision or rev ID (first before range)
4041          * @param $new int|Revision New revision or rev ID (first after range)
4042          * @return Int Number of revisions between these revisions.
4043          */
4044         public function countRevisionsBetween( $old, $new ) {
4045                 if ( !( $old instanceof Revision ) ) {
4046                         $old = Revision::newFromTitle( $this, (int)$old );
4047                 }
4048                 if ( !( $new instanceof Revision ) ) {
4049                         $new = Revision::newFromTitle( $this, (int)$new );
4050                 }
4051                 if ( !$old || !$new ) {
4052                         return 0; // nothing to compare
4053                 }
4054                 $dbr = wfGetDB( DB_SLAVE );
4055                 return (int)$dbr->selectField( 'revision', 'count(*)',
4056                         array(
4057                                 'rev_page' => $this->getArticleId(),
4058                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4059                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4060                         ),
4061                         __METHOD__
4062                 );
4063         }
4064
4065         /**
4066          * Get the number of authors between the given revision IDs.
4067          * Used for diffs and other things that really need it.
4068          *
4069          * @param $old int|Revision Old revision or rev ID (first before range)
4070          * @param $new int|Revision New revision or rev ID (first after range)
4071          * @param $limit Int Maximum number of authors
4072          * @return Int Number of revision authors between these revisions.
4073          */
4074         public function countAuthorsBetween( $old, $new, $limit ) {
4075                 if ( !( $old instanceof Revision ) ) {
4076                         $old = Revision::newFromTitle( $this, (int)$old );
4077                 }
4078                 if ( !( $new instanceof Revision ) ) {
4079                         $new = Revision::newFromTitle( $this, (int)$new );
4080                 }
4081                 if ( !$old || !$new ) {
4082                         return 0; // nothing to compare
4083                 }
4084                 $dbr = wfGetDB( DB_SLAVE );
4085                 $res = $dbr->select( 'revision', 'DISTINCT rev_user_text',
4086                         array(
4087                                 'rev_page' => $this->getArticleID(),
4088                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4089                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4090                         ), __METHOD__,
4091                         array( 'LIMIT' => $limit + 1 ) // add one so caller knows it was truncated
4092                 );
4093                 return (int)$dbr->numRows( $res );
4094         }
4095
4096         /**
4097          * Compare with another title.
4098          *
4099          * @param $title Title
4100          * @return Bool
4101          */
4102         public function equals( Title $title ) {
4103                 // Note: === is necessary for proper matching of number-like titles.
4104                 return $this->getInterwiki() === $title->getInterwiki()
4105                         && $this->getNamespace() == $title->getNamespace()
4106                         && $this->getDBkey() === $title->getDBkey();
4107         }
4108
4109         /**
4110          * Check if this title is a subpage of another title
4111          *
4112          * @param $title Title
4113          * @return Bool
4114          */
4115         public function isSubpageOf( Title $title ) {
4116                 return $this->getInterwiki() === $title->getInterwiki()
4117                         && $this->getNamespace() == $title->getNamespace()
4118                         && strpos( $this->getDBkey(), $title->getDBkey() . '/' ) === 0;
4119         }
4120
4121         /**
4122          * Check if page exists.  For historical reasons, this function simply
4123          * checks for the existence of the title in the page table, and will
4124          * thus return false for interwiki links, special pages and the like.
4125          * If you want to know if a title can be meaningfully viewed, you should
4126          * probably call the isKnown() method instead.
4127          *
4128          * @return Bool
4129          */
4130         public function exists() {
4131                 return $this->getArticleId() != 0;
4132         }
4133
4134         /**
4135          * Should links to this title be shown as potentially viewable (i.e. as
4136          * "bluelinks"), even if there's no record by this title in the page
4137          * table?
4138          *
4139          * This function is semi-deprecated for public use, as well as somewhat
4140          * misleadingly named.  You probably just want to call isKnown(), which
4141          * calls this function internally.
4142          *
4143          * (ISSUE: Most of these checks are cheap, but the file existence check
4144          * can potentially be quite expensive.  Including it here fixes a lot of
4145          * existing code, but we might want to add an optional parameter to skip
4146          * it and any other expensive checks.)
4147          *
4148          * @return Bool
4149          */
4150         public function isAlwaysKnown() {
4151                 if ( $this->mInterwiki != '' ) {
4152                         return true;  // any interwiki link might be viewable, for all we know
4153                 }
4154                 switch( $this->mNamespace ) {
4155                         case NS_MEDIA:
4156                         case NS_FILE:
4157                                 // file exists, possibly in a foreign repo
4158                                 return (bool)wfFindFile( $this );
4159                         case NS_SPECIAL:
4160                                 // valid special page
4161                                 return SpecialPageFactory::exists( $this->getDBkey() );
4162                         case NS_MAIN:
4163                                 // selflink, possibly with fragment
4164                                 return $this->mDbkeyform == '';
4165                         case NS_MEDIAWIKI:
4166                                 // known system message
4167                                 return $this->hasSourceText() !== false;
4168                         default:
4169                                 return false;
4170                 }
4171         }
4172
4173         /**
4174          * Does this title refer to a page that can (or might) be meaningfully
4175          * viewed?  In particular, this function may be used to determine if
4176          * links to the title should be rendered as "bluelinks" (as opposed to
4177          * "redlinks" to non-existent pages).
4178          *
4179          * @return Bool
4180          */
4181         public function isKnown() {
4182                 return $this->isAlwaysKnown() || $this->exists();
4183         }
4184
4185         /**
4186          * Does this page have source text?
4187          *
4188          * @return Boolean
4189          */
4190         public function hasSourceText() {
4191                 if ( $this->exists() ) {
4192                         return true;
4193                 }
4194
4195                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
4196                         // If the page doesn't exist but is a known system message, default
4197                         // message content will be displayed, same for language subpages-
4198                         // Use always content language to avoid loading hundreds of languages
4199                         // to get the link color.
4200                         global $wgContLang;
4201                         list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4202                         $message = wfMessage( $name )->inLanguage( $wgContLang )->useDatabase( false );
4203                         return $message->exists();
4204                 }
4205
4206                 return false;
4207         }
4208
4209         /**
4210          * Get the default message text or false if the message doesn't exist
4211          *
4212          * @return String or false
4213          */
4214         public function getDefaultMessageText() {
4215                 global $wgContLang;
4216
4217                 if ( $this->getNamespace() != NS_MEDIAWIKI ) { // Just in case
4218                         return false;
4219                 }
4220
4221                 list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4222                 $message = wfMessage( $name )->inLanguage( $lang )->useDatabase( false );
4223
4224                 if ( $message->exists() ) {
4225                         return $message->plain();
4226                 } else {
4227                         return false;
4228                 }
4229         }
4230
4231         /**
4232          * Updates page_touched for this page; called from LinksUpdate.php
4233          *
4234          * @return Bool true if the update succeded
4235          */
4236         public function invalidateCache() {
4237                 if ( wfReadOnly() ) {
4238                         return false;
4239                 }
4240                 $dbw = wfGetDB( DB_MASTER );
4241                 $success = $dbw->update(
4242                         'page',
4243                         array( 'page_touched' => $dbw->timestamp() ),
4244                         $this->pageCond(),
4245                         __METHOD__
4246                 );
4247                 HTMLFileCache::clearFileCache( $this );
4248                 return $success;
4249         }
4250
4251         /**
4252          * Update page_touched timestamps and send squid purge messages for
4253          * pages linking to this title. May be sent to the job queue depending
4254          * on the number of links. Typically called on create and delete.
4255          */
4256         public function touchLinks() {
4257                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
4258                 $u->doUpdate();
4259
4260                 if ( $this->getNamespace() == NS_CATEGORY ) {
4261                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
4262                         $u->doUpdate();
4263                 }
4264         }
4265
4266         /**
4267          * Get the last touched timestamp
4268          *
4269          * @param $db DatabaseBase: optional db
4270          * @return String last-touched timestamp
4271          */
4272         public function getTouched( $db = null ) {
4273                 $db = isset( $db ) ? $db : wfGetDB( DB_SLAVE );
4274                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
4275                 return $touched;
4276         }
4277
4278         /**
4279          * Get the timestamp when this page was updated since the user last saw it.
4280          *
4281          * @param $user User
4282          * @return String|Null
4283          */
4284         public function getNotificationTimestamp( $user = null ) {
4285                 global $wgUser, $wgShowUpdatedMarker;
4286                 // Assume current user if none given
4287                 if ( !$user ) {
4288                         $user = $wgUser;
4289                 }
4290                 // Check cache first
4291                 $uid = $user->getId();
4292                 // avoid isset here, as it'll return false for null entries
4293                 if ( array_key_exists( $uid, $this->mNotificationTimestamp ) ) {
4294                         return $this->mNotificationTimestamp[$uid];
4295                 }
4296                 if ( !$uid || !$wgShowUpdatedMarker ) {
4297                         return $this->mNotificationTimestamp[$uid] = false;
4298                 }
4299                 // Don't cache too much!
4300                 if ( count( $this->mNotificationTimestamp ) >= self::CACHE_MAX ) {
4301                         $this->mNotificationTimestamp = array();
4302                 }
4303                 $dbr = wfGetDB( DB_SLAVE );
4304                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
4305                         'wl_notificationtimestamp',
4306                         array( 'wl_namespace' => $this->getNamespace(),
4307                                 'wl_title' => $this->getDBkey(),
4308                                 'wl_user' => $user->getId()
4309                         ),
4310                         __METHOD__
4311                 );
4312                 return $this->mNotificationTimestamp[$uid];
4313         }
4314
4315         /**
4316          * Generate strings used for xml 'id' names in monobook tabs
4317          *
4318          * @param $prepend string defaults to 'nstab-'
4319          * @return String XML 'id' name
4320          */
4321         public function getNamespaceKey( $prepend = 'nstab-' ) {
4322                 global $wgContLang;
4323                 // Gets the subject namespace if this title
4324                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
4325                 // Checks if cononical namespace name exists for namespace
4326                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
4327                         // Uses canonical namespace name
4328                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
4329                 } else {
4330                         // Uses text of namespace
4331                         $namespaceKey = $this->getSubjectNsText();
4332                 }
4333                 // Makes namespace key lowercase
4334                 $namespaceKey = $wgContLang->lc( $namespaceKey );
4335                 // Uses main
4336                 if ( $namespaceKey == '' ) {
4337                         $namespaceKey = 'main';
4338                 }
4339                 // Changes file to image for backwards compatibility
4340                 if ( $namespaceKey == 'file' ) {
4341                         $namespaceKey = 'image';
4342                 }
4343                 return $prepend . $namespaceKey;
4344         }
4345
4346         /**
4347          * Get all extant redirects to this Title
4348          *
4349          * @param $ns Int|Null Single namespace to consider; NULL to consider all namespaces
4350          * @return Array of Title redirects to this title
4351          */
4352         public function getRedirectsHere( $ns = null ) {
4353                 $redirs = array();
4354
4355                 $dbr = wfGetDB( DB_SLAVE );
4356                 $where = array(
4357                         'rd_namespace' => $this->getNamespace(),
4358                         'rd_title' => $this->getDBkey(),
4359                         'rd_from = page_id'
4360                 );
4361                 if ( !is_null( $ns ) ) {
4362                         $where['page_namespace'] = $ns;
4363                 }
4364
4365                 $res = $dbr->select(
4366                         array( 'redirect', 'page' ),
4367                         array( 'page_namespace', 'page_title' ),
4368                         $where,
4369                         __METHOD__
4370                 );
4371
4372                 foreach ( $res as $row ) {
4373                         $redirs[] = self::newFromRow( $row );
4374                 }
4375                 return $redirs;
4376         }
4377
4378         /**
4379          * Check if this Title is a valid redirect target
4380          *
4381          * @return Bool
4382          */
4383         public function isValidRedirectTarget() {
4384                 global $wgInvalidRedirectTargets;
4385
4386                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
4387                 if ( $this->isSpecial( 'Userlogout' ) ) {
4388                         return false;
4389                 }
4390
4391                 foreach ( $wgInvalidRedirectTargets as $target ) {
4392                         if ( $this->isSpecial( $target ) ) {
4393                                 return false;
4394                         }
4395                 }
4396
4397                 return true;
4398         }
4399
4400         /**
4401          * Get a backlink cache object
4402          *
4403          * @return BacklinkCache
4404          */
4405         function getBacklinkCache() {
4406                 if ( is_null( $this->mBacklinkCache ) ) {
4407                         $this->mBacklinkCache = new BacklinkCache( $this );
4408                 }
4409                 return $this->mBacklinkCache;
4410         }
4411
4412         /**
4413          * Whether the magic words __INDEX__ and __NOINDEX__ function for  this page.
4414          *
4415          * @return Boolean
4416          */
4417         public function canUseNoindex() {
4418                 global $wgContentNamespaces, $wgExemptFromUserRobotsControl;
4419
4420                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
4421                         ? $wgContentNamespaces
4422                         : $wgExemptFromUserRobotsControl;
4423
4424                 return !in_array( $this->mNamespace, $bannedNamespaces );
4425
4426         }
4427
4428         /**
4429          * Returns the raw sort key to be used for categories, with the specified
4430          * prefix.  This will be fed to Collation::getSortKey() to get a
4431          * binary sortkey that can be used for actual sorting.
4432          *
4433          * @param $prefix string The prefix to be used, specified using
4434          *   {{defaultsort:}} or like [[Category:Foo|prefix]].  Empty for no
4435          *   prefix.
4436          * @return string
4437          */
4438         public function getCategorySortkey( $prefix = '' ) {
4439                 $unprefixed = $this->getText();
4440
4441                 // Anything that uses this hook should only depend
4442                 // on the Title object passed in, and should probably
4443                 // tell the users to run updateCollations.php --force
4444                 // in order to re-sort existing category relations.
4445                 wfRunHooks( 'GetDefaultSortkey', array( $this, &$unprefixed ) );
4446                 if ( $prefix !== '' ) {
4447                         # Separate with a line feed, so the unprefixed part is only used as
4448                         # a tiebreaker when two pages have the exact same prefix.
4449                         # In UCA, tab is the only character that can sort above LF
4450                         # so we strip both of them from the original prefix.
4451                         $prefix = strtr( $prefix, "\n\t", '  ' );
4452                         return "$prefix\n$unprefixed";
4453                 }
4454                 return $unprefixed;
4455         }
4456
4457         /**
4458          * Get the language in which the content of this page is written.
4459          * Defaults to $wgContLang, but in certain cases it can be e.g.
4460          * $wgLang (such as special pages, which are in the user language).
4461          *
4462          * @since 1.18
4463          * @return object Language
4464          */
4465         public function getPageLanguage() {
4466                 global $wgLang;
4467                 if ( $this->isSpecialPage() ) {
4468                         // special pages are in the user language
4469                         return $wgLang;
4470                 } elseif ( $this->isCssOrJsPage() ) {
4471                         // css/js should always be LTR and is, in fact, English
4472                         return wfGetLangObj( 'en' );
4473                 } elseif ( $this->getNamespace() == NS_MEDIAWIKI ) {
4474                         // Parse mediawiki messages with correct target language
4475                         list( /* $unused */, $lang ) = MessageCache::singleton()->figureMessage( $this->getText() );
4476                         return wfGetLangObj( $lang );
4477                 }
4478                 global $wgContLang;
4479                 // If nothing special, it should be in the wiki content language
4480                 $pageLang = $wgContLang;
4481                 // Hook at the end because we don't want to override the above stuff
4482                 wfRunHooks( 'PageContentLanguage', array( $this, &$pageLang, $wgLang ) );
4483                 return wfGetLangObj( $pageLang );
4484         }
4485 }