includes/Title.php

   1 <?php
   2 /**
   3  * See title.txt
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 /**
  24  * Represents a title within MediaWiki.
  25  * Optionally may contain an interwiki designation or namespace.
  26  * @note This class can fetch various kinds of data from the database;
  27  *       however, it does so inefficiently.
  28  *
  29  * @internal documentation reviewed 15 Mar 2010
  30  */
  31 class Title {
  32         /** @name Static cache variables */
  33         // @{
  34         static private $titleCache = array();
  35         // @}
  36
  37         /**
  38          * Title::newFromText maintains a cache to avoid expensive re-normalization of
  39          * commonly used titles. On a batch operation this can become a memory leak
  40          * if not bounded. After hitting this many titles reset the cache.
  41          */
  42         const CACHE_MAX = 1000;
  43
  44         /**
  45          * Used to be GAID_FOR_UPDATE define. Used with getArticleID() and friends
  46          * to use the master DB
  47          */
  48         const GAID_FOR_UPDATE = 1;
  49
  50         /**
  51          * @name Private member variables
  52          * Please use the accessor functions instead.
  53          * @private
  54          */
  55         // @{
  56
  57         var $mTextform = '';              // /< Text form (spaces not underscores) of the main part
  58         var $mUrlform = '';               // /< URL-encoded form of the main part
  59         var $mDbkeyform = '';             // /< Main part with underscores
  60         var $mUserCaseDBKey;              // /< DB key with the initial letter in the case specified by the user
  61         var $mNamespace = NS_MAIN;        // /< Namespace index, i.e. one of the NS_xxxx constants
  62         var $mInterwiki = '';             // /< Interwiki prefix (or null string)
  63         var $mFragment;                   // /< Title fragment (i.e. the bit after the #)
  64         var $mArticleID = -1;             // /< Article ID, fetched from the link cache on demand
  65         var $mLatestID = false;           // /< ID of most recent revision
  66         private $mEstimateRevisions;      // /< Estimated number of revisions; null of not loaded
  67         var $mRestrictions = array();     // /< Array of groups allowed to edit this article
  68         var $mOldRestrictions = false;
  69         var $mCascadeRestriction;         ///< Cascade restrictions on this page to included templates and images?
  70         var $mCascadingRestrictions;      // Caching the results of getCascadeProtectionSources
  71         var $mRestrictionsExpiry = array(); ///< When do the restrictions on this page expire?
  72         var $mHasCascadingRestrictions;   ///< Are cascading restrictions in effect on this page?
  73         var $mCascadeSources;             ///< Where are the cascading restrictions coming from on this page?
  74         var $mRestrictionsLoaded = false; ///< Boolean for initialisation on demand
  75         var $mPrefixedText;               ///< Text form including namespace/interwiki, initialised on demand
  76         var $mTitleProtection;            ///< Cached value for getTitleProtection (create protection)
  77         # Don't change the following default, NS_MAIN is hardcoded in several
  78         # places.  See bug 696.
  79         var $mDefaultNamespace = NS_MAIN; // /< Namespace index when there is no namespace
  80                                                                           # Zero except in {{transclusion}} tags
  81         var $mWatched = null;             // /< Is $wgUser watching this page? null if unfilled, accessed through userIsWatching()
  82         var $mLength = -1;                // /< The page length, 0 for special pages
  83         var $mRedirect = null;            // /< Is the article at this title a redirect?
  84         var $mNotificationTimestamp = array(); // /< Associative array of user ID -> timestamp/false
  85         var $mBacklinkCache = null;       // /< Cache of links to this title
  86         // @}
  87
  88
  89         /**
  90          * Constructor
  91          */
  92         /*protected*/ function __construct() { }
  93
  94         /**
  95          * Create a new Title from a prefixed DB key
  96          *
  97          * @param $key String the database key, which has underscores
  98          *      instead of spaces, possibly including namespace and
  99          *      interwiki prefixes
 100          * @return Title, or NULL on an error
 101          */
 102         public static function newFromDBkey( $key ) {
 103                 $t = new Title();
 104                 $t->mDbkeyform = $key;
 105                 if ( $t->secureAndSplit() ) {
 106                         return $t;
 107                 } else {
 108                         return null;
 109                 }
 110         }
 111
 112         /**
 113          * Create a new Title from text, such as what one would find in a link. De-
 114          * codes any HTML entities in the text.
 115          *
 116          * @param $text String the link text; spaces, prefixes, and an
 117          *   initial ':' indicating the main namespace are accepted.
 118          * @param $defaultNamespace Int the namespace to use if none is speci-
 119          *   fied by a prefix.  If you want to force a specific namespace even if
 120          *   $text might begin with a namespace prefix, use makeTitle() or
 121          *   makeTitleSafe().
 122          * @return Title, or null on an error.
 123          */
 124         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 125                 if ( is_object( $text ) ) {
 126                         throw new MWException( 'Title::newFromText given an object' );
 127                 }
 128
 129                 /**
 130                  * Wiki pages often contain multiple links to the same page.
 131                  * Title normalization and parsing can become expensive on
 132                  * pages with many links, so we can save a little time by
 133                  * caching them.
 134                  *
 135                  * In theory these are value objects and won't get changed...
 136                  */
 137                 if ( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 138                         return Title::$titleCache[$text];
 139                 }
 140
 141                 # Convert things like &eacute; &#257; or &#x3017; into normalized (bug 14952) text
 142                 $filteredText = Sanitizer::decodeCharReferencesAndNormalize( $text );
 143
 144                 $t = new Title();
 145                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 146                 $t->mDefaultNamespace = $defaultNamespace;
 147
 148                 static $cachedcount = 0 ;
 149                 if ( $t->secureAndSplit() ) {
 150                         if ( $defaultNamespace == NS_MAIN ) {
 151                                 if ( $cachedcount >= self::CACHE_MAX ) {
 152                                         # Avoid memory leaks on mass operations...
 153                                         Title::$titleCache = array();
 154                                         $cachedcount = 0;
 155                                 }
 156                                 $cachedcount++;
 157                                 Title::$titleCache[$text] =& $t;
 158                         }
 159                         return $t;
 160                 } else {
 161                         $ret = null;
 162                         return $ret;
 163                 }
 164         }
 165
 166         /**
 167          * THIS IS NOT THE FUNCTION YOU WANT. Use Title::newFromText().
 168          *
 169          * Example of wrong and broken code:
 170          * $title = Title::newFromURL( $wgRequest->getVal( 'title' ) );
 171          *
 172          * Example of right code:
 173          * $title = Title::newFromText( $wgRequest->getVal( 'title' ) );
 174          *
 175          * Create a new Title from URL-encoded text. Ensures that
 176          * the given title's length does not exceed the maximum.
 177          *
 178          * @param $url String the title, as might be taken from a URL
 179          * @return Title the new object, or NULL on an error
 180          */
 181         public static function newFromURL( $url ) {
 182                 global $wgLegalTitleChars;
 183                 $t = new Title();
 184
 185                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 186                 # but some URLs used it as a space replacement and they still come
 187                 # from some external search tools.
 188                 if ( strpos( $wgLegalTitleChars, '+' ) === false ) {
 189                         $url = str_replace( '+', ' ', $url );
 190                 }
 191
 192                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 193                 if ( $t->secureAndSplit() ) {
 194                         return $t;
 195                 } else {
 196                         return null;
 197                 }
 198         }
 199
 200         /**
 201          * Create a new Title from an article ID
 202          *
 203          * @param $id Int the page_id corresponding to the Title to create
 204          * @param $flags Int use Title::GAID_FOR_UPDATE to use master
 205          * @return Title the new object, or NULL on an error
 206          */
 207         public static function newFromID( $id, $flags = 0 ) {
 208                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
 209                 $row = $db->selectRow( 'page', '*', array( 'page_id' => $id ), __METHOD__ );
 210                 if ( $row !== false ) {
 211                         $title = Title::newFromRow( $row );
 212                 } else {
 213                         $title = null;
 214                 }
 215                 return $title;
 216         }
 217
 218         /**
 219          * Make an array of titles from an array of IDs
 220          *
 221          * @param $ids Array of Int Array of IDs
 222          * @return Array of Titles
 223          */
 224         public static function newFromIDs( $ids ) {
 225                 if ( !count( $ids ) ) {
 226                         return array();
 227                 }
 228                 $dbr = wfGetDB( DB_SLAVE );
 229
 230                 $res = $dbr->select(
 231                         'page',
 232                         array(
 233                                 'page_namespace', 'page_title', 'page_id',
 234                                 'page_len', 'page_is_redirect', 'page_latest',
 235                         ),
 236                         array( 'page_id' => $ids ),
 237                         __METHOD__
 238                 );
 239
 240                 $titles = array();
 241                 foreach ( $res as $row ) {
 242                         $titles[] = Title::newFromRow( $row );
 243                 }
 244                 return $titles;
 245         }
 246
 247         /**
 248          * Make a Title object from a DB row
 249          *
 250          * @param $row Object database row (needs at least page_title,page_namespace)
 251          * @return Title corresponding Title
 252          */
 253         public static function newFromRow( $row ) {
 254                 $t = self::makeTitle( $row->page_namespace, $row->page_title );
 255                 $t->loadFromRow( $row );
 256                 return $t;
 257         }
 258
 259         /**
 260          * Load Title object fields from a DB row.
 261          * If false is given, the title will be treated as non-existing.
 262          *
 263          * @param $row Object|false database row
 264          * @return void
 265          */
 266         public function loadFromRow( $row ) {
 267                 if ( $row ) { // page found
 268                         if ( isset( $row->page_id ) )
 269                                 $this->mArticleID = (int)$row->page_id;
 270                         if ( isset( $row->page_len ) )
 271                                 $this->mLength = (int)$row->page_len;
 272                         if ( isset( $row->page_is_redirect ) )
 273                                 $this->mRedirect = (bool)$row->page_is_redirect;
 274                         if ( isset( $row->page_latest ) )
 275                                 $this->mLatestID = (int)$row->page_latest; # FIXME: whene3ver page_latest is updated, also update page_content_model
 276             if ( isset( $row->page_content_model ) )
 277                 $this->mContentModelName = $row->page_content_model;
 278             else
 279                 $this->mContentModelName = null; # initialized lazily in getContentModelName()
 280                 } else { // page not found
 281                         $this->mArticleID = 0;
 282                         $this->mLength = 0;
 283                         $this->mRedirect = false;
 284                         $this->mLatestID = 0;
 285             $this->mContentModelName = null; # initialized lazily in getContentModelName()
 286                 }
 287         }
 288
 289         /**
 290          * Create a new Title from a namespace index and a DB key.
 291          * It's assumed that $ns and $title are *valid*, for instance when
 292          * they came directly from the database or a special page name.
 293          * For convenience, spaces are converted to underscores so that
 294          * eg user_text fields can be used directly.
 295          *
 296          * @param $ns Int the namespace of the article
 297          * @param $title String the unprefixed database key form
 298          * @param $fragment String the link fragment (after the "#")
 299          * @param $interwiki String the interwiki prefix
 300          * @return Title the new object
 301          */
 302         public static function &makeTitle( $ns, $title, $fragment = '', $interwiki = '' ) {
 303                 $t = new Title();
 304                 $t->mInterwiki = $interwiki;
 305                 $t->mFragment = $fragment;
 306                 $t->mNamespace = $ns = intval( $ns );
 307                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 308                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 309                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 310                 $t->mTextform = str_replace( '_', ' ', $title );
 311         $t->mContentModelName = null; # initialized lazily in getContentModelName()
 312                 return $t;
 313         }
 314
 315         /**
 316          * Create a new Title from a namespace index and a DB key.
 317          * The parameters will be checked for validity, which is a bit slower
 318          * than makeTitle() but safer for user-provided data.
 319          *
 320          * @param $ns Int the namespace of the article
 321          * @param $title String database key form
 322          * @param $fragment String the link fragment (after the "#")
 323          * @param $interwiki String interwiki prefix
 324          * @return Title the new object, or NULL on an error
 325          */
 326         public static function makeTitleSafe( $ns, $title, $fragment = '', $interwiki = '' ) {
 327                 $t = new Title();
 328                 $t->mDbkeyform = Title::makeName( $ns, $title, $fragment, $interwiki );
 329                 if ( $t->secureAndSplit() ) {
 330                         return $t;
 331                 } else {
 332                         return null;
 333                 }
 334         }
 335
 336         /**
 337          * Create a new Title for the Main Page
 338          *
 339          * @return Title the new object
 340          */
 341         public static function newMainPage() {
 342                 $title = Title::newFromText( wfMsgForContent( 'mainpage' ) );
 343                 // Don't give fatal errors if the message is broken
 344                 if ( !$title ) {
 345                         $title = Title::newFromText( 'Main Page' );
 346                 }
 347                 return $title;
 348         }
 349
 350         /**
 351          * Extract a redirect destination from a string and return the
 352          * Title, or null if the text doesn't contain a valid redirect
 353          * This will only return the very next target, useful for
 354          * the redirect table and other checks that don't need full recursion
 355          *
 356          * @param $text String: Text with possible redirect
 357          * @return Title: The corresponding Title
 358          */
 359         public static function newFromRedirect( $text ) {
 360                 return self::newFromRedirectInternal( $text );
 361         }
 362
 363         /**
 364          * Extract a redirect destination from a string and return the
 365          * Title, or null if the text doesn't contain a valid redirect
 366          * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
 367          * in order to provide (hopefully) the Title of the final destination instead of another redirect
 368          *
 369          * @param $text String Text with possible redirect
 370          * @return Title
 371          */
 372         public static function newFromRedirectRecurse( $text ) {
 373                 $titles = self::newFromRedirectArray( $text );
 374                 return $titles ? array_pop( $titles ) : null;
 375         }
 376
 377         /**
 378          * Extract a redirect destination from a string and return an
 379          * array of Titles, or null if the text doesn't contain a valid redirect
 380          * The last element in the array is the final destination after all redirects
 381          * have been resolved (up to $wgMaxRedirects times)
 382          *
 383          * @param $text String Text with possible redirect
 384          * @return Array of Titles, with the destination last
 385          */
 386         public static function newFromRedirectArray( $text ) {
 387                 global $wgMaxRedirects;
 388                 $title = self::newFromRedirectInternal( $text );
 389                 if ( is_null( $title ) ) {
 390                         return null;
 391                 }
 392                 // recursive check to follow double redirects
 393                 $recurse = $wgMaxRedirects;
 394                 $titles = array( $title );
 395                 while ( --$recurse > 0 ) {
 396                         if ( $title->isRedirect() ) {
 397                                 $page = WikiPage::factory( $title );
 398                                 $newtitle = $page->getRedirectTarget();
 399                         } else {
 400                                 break;
 401                         }
 402                         // Redirects to some special pages are not permitted
 403                         if ( $newtitle instanceOf Title && $newtitle->isValidRedirectTarget() ) {
 404                                 // the new title passes the checks, so make that our current title so that further recursion can be checked
 405                                 $title = $newtitle;
 406                                 $titles[] = $newtitle;
 407                         } else {
 408                                 break;
 409                         }
 410                 }
 411                 return $titles;
 412         }
 413
 414         /**
 415          * Really extract the redirect destination
 416          * Do not call this function directly, use one of the newFromRedirect* functions above
 417          *
 418          * @param $text String Text with possible redirect
 419          * @return Title
 420          */
 421         protected static function newFromRedirectInternal( $text ) {
 422                 global $wgMaxRedirects;
 423                 if ( $wgMaxRedirects < 1 ) {
 424                         //redirects are disabled, so quit early
 425                         return null;
 426                 }
 427                 $redir = MagicWord::get( 'redirect' );
 428                 $text = trim( $text );
 429                 if ( $redir->matchStartAndRemove( $text ) ) {
 430                         // Extract the first link and see if it's usable
 431                         // Ensure that it really does come directly after #REDIRECT
 432                         // Some older redirects included a colon, so don't freak about that!
 433                         $m = array();
 434                         if ( preg_match( '!^\s*:?\s*\[{2}(.*?)(?:\|.*?)?\]{2}!', $text, $m ) ) {
 435                                 // Strip preceding colon used to "escape" categories, etc.
 436                                 // and URL-decode links
 437                                 if ( strpos( $m[1], '%' ) !== false ) {
 438                                         // Match behavior of inline link parsing here;
 439                                         $m[1] = rawurldecode( ltrim( $m[1], ':' ) );
 440                                 }
 441                                 $title = Title::newFromText( $m[1] );
 442                                 // If the title is a redirect to bad special pages or is invalid, return null
 443                                 if ( !$title instanceof Title || !$title->isValidRedirectTarget() ) {
 444                                         return null;
 445                                 }
 446                                 return $title;
 447                         }
 448                 }
 449                 return null;
 450         }
 451
 452         /**
 453          * Get the prefixed DB key associated with an ID
 454          *
 455          * @param $id Int the page_id of the article
 456          * @return Title an object representing the article, or NULL if no such article was found
 457          */
 458         public static function nameOf( $id ) {
 459                 $dbr = wfGetDB( DB_SLAVE );
 460
 461                 $s = $dbr->selectRow(
 462                         'page',
 463                         array( 'page_namespace', 'page_title' ),
 464                         array( 'page_id' => $id ),
 465                         __METHOD__
 466                 );
 467                 if ( $s === false ) {
 468                         return null;
 469                 }
 470
 471                 $n = self::makeName( $s->page_namespace, $s->page_title );
 472                 return $n;
 473         }
 474
 475         /**
 476          * Get a regex character class describing the legal characters in a link
 477          *
 478          * @return String the list of characters, not delimited
 479          */
 480         public static function legalChars() {
 481                 global $wgLegalTitleChars;
 482                 return $wgLegalTitleChars;
 483         }
 484
 485         /**
 486          * Returns a simple regex that will match on characters and sequences invalid in titles.
 487          * Note that this doesn't pick up many things that could be wrong with titles, but that
 488          * replacing this regex with something valid will make many titles valid.
 489          *
 490          * @return String regex string
 491          */
 492         static function getTitleInvalidRegex() {
 493                 static $rxTc = false;
 494                 if ( !$rxTc ) {
 495                         # Matching titles will be held as illegal.
 496                         $rxTc = '/' .
 497                                 # Any character not allowed is forbidden...
 498                                 '[^' . self::legalChars() . ']' .
 499                                 # URL percent encoding sequences interfere with the ability
 500                                 # to round-trip titles -- you can't link to them consistently.
 501                                 '|%[0-9A-Fa-f]{2}' .
 502                                 # XML/HTML character references produce similar issues.
 503                                 '|&[A-Za-z0-9\x80-\xff]+;' .
 504                                 '|&#[0-9]+;' .
 505                                 '|&#x[0-9A-Fa-f]+;' .
 506                                 '/S';
 507                 }
 508
 509                 return $rxTc;
 510         }
 511
 512         /**
 513          * Get a string representation of a title suitable for
 514          * including in a search index
 515          *
 516          * @param $ns Int a namespace index
 517          * @param $title String text-form main part
 518          * @return String a stripped-down title string ready for the search index
 519          */
 520         public static function indexTitle( $ns, $title ) {
 521                 global $wgContLang;
 522
 523                 $lc = SearchEngine::legalSearchChars() . '&#;';
 524                 $t = $wgContLang->normalizeForSearch( $title );
 525                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 526                 $t = $wgContLang->lc( $t );
 527
 528                 # Handle 's, s'
 529                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 530                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 531
 532                 $t = preg_replace( "/\\s+/", ' ', $t );
 533
 534                 if ( $ns == NS_FILE ) {
 535                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 536                 }
 537                 return trim( $t );
 538         }
 539
 540         /**
 541          * Make a prefixed DB key from a DB key and a namespace index
 542          *
 543          * @param $ns Int numerical representation of the namespace
 544          * @param $title String the DB key form the title
 545          * @param $fragment String The link fragment (after the "#")
 546          * @param $interwiki String The interwiki prefix
 547          * @return String the prefixed form of the title
 548          */
 549         public static function makeName( $ns, $title, $fragment = '', $interwiki = '' ) {
 550                 global $wgContLang;
 551
 552                 $namespace = $wgContLang->getNsText( $ns );
 553                 $name = $namespace == '' ? $title : "$namespace:$title";
 554                 if ( strval( $interwiki ) != '' ) {
 555                         $name = "$interwiki:$name";
 556                 }
 557                 if ( strval( $fragment ) != '' ) {
 558                         $name .= '#' . $fragment;
 559                 }
 560                 return $name;
 561         }
 562
 563         /**
 564          * Escape a text fragment, say from a link, for a URL
 565          *
 566          * @param $fragment string containing a URL or link fragment (after the "#")
 567          * @return String: escaped string
 568          */
 569         static function escapeFragmentForURL( $fragment ) {
 570                 # Note that we don't urlencode the fragment.  urlencoded Unicode
 571                 # fragments appear not to work in IE (at least up to 7) or in at least
 572                 # one version of Opera 9.x.  The W3C validator, for one, doesn't seem
 573                 # to care if they aren't encoded.
 574                 return Sanitizer::escapeId( $fragment, 'noninitial' );
 575         }
 576
 577         /**
 578          * Callback for usort() to do title sorts by (namespace, title)
 579          *
 580          * @param $a Title
 581          * @param $b Title
 582          *
 583          * @return Integer: result of string comparison, or namespace comparison
 584          */
 585         public static function compare( $a, $b ) {
 586                 if ( $a->getNamespace() == $b->getNamespace() ) {
 587                         return strcmp( $a->getText(), $b->getText() );
 588                 } else {
 589                         return $a->getNamespace() - $b->getNamespace();
 590                 }
 591         }
 592
 593         /**
 594          * Determine whether the object refers to a page within
 595          * this project.
 596          *
 597          * @return Bool TRUE if this is an in-project interwiki link or a wikilink, FALSE otherwise
 598          */
 599         public function isLocal() {
 600                 if ( $this->mInterwiki != '' ) {
 601                         return Interwiki::fetch( $this->mInterwiki )->isLocal();
 602                 } else {
 603                         return true;
 604                 }
 605         }
 606
 607         /**
 608          * Is this Title interwiki?
 609          *
 610          * @return Bool
 611          */
 612         public function isExternal() {
 613                 return ( $this->mInterwiki != '' );
 614         }
 615
 616         /**
 617          * Get the interwiki prefix (or null string)
 618          *
 619          * @return String Interwiki prefix
 620          */
 621         public function getInterwiki() {
 622                 return $this->mInterwiki;
 623         }
 624
 625         /**
 626          * Determine whether the object refers to a page within
 627          * this project and is transcludable.
 628          *
 629          * @return Bool TRUE if this is transcludable
 630          */
 631         public function isTrans() {
 632                 if ( $this->mInterwiki == '' ) {
 633                         return false;
 634                 }
 635
 636                 return Interwiki::fetch( $this->mInterwiki )->isTranscludable();
 637         }
 638
 639         /**
 640          * Returns the DB name of the distant wiki which owns the object.
 641          *
 642          * @return String the DB name
 643          */
 644         public function getTransWikiID() {
 645                 if ( $this->mInterwiki == '' ) {
 646                         return false;
 647                 }
 648
 649                 return Interwiki::fetch( $this->mInterwiki )->getWikiID();
 650         }
 651
 652         /**
 653          * Get the text form (spaces not underscores) of the main part
 654          *
 655          * @return String Main part of the title
 656          */
 657         public function getText() {
 658                 return $this->mTextform;
 659         }
 660
 661         /**
 662          * Get the URL-encoded form of the main part
 663          *
 664          * @return String Main part of the title, URL-encoded
 665          */
 666         public function getPartialURL() {
 667                 return $this->mUrlform;
 668         }
 669
 670         /**
 671          * Get the main part with underscores
 672          *
 673          * @return String: Main part of the title, with underscores
 674          */
 675         public function getDBkey() {
 676                 return $this->mDbkeyform;
 677         }
 678
 679         /**
 680          * Get the DB key with the initial letter case as specified by the user
 681          *
 682          * @return String DB key
 683          */
 684         function getUserCaseDBKey() {
 685                 return $this->mUserCaseDBKey;
 686         }
 687
 688         /**
 689          * Get the namespace index, i.e. one of the NS_xxxx constants.
 690          *
 691          * @return Integer: Namespace index
 692          */
 693         public function getNamespace() {
 694                 return $this->mNamespace;
 695         }
 696
 697     /**
 698      * Get the page's content model name
 699      *
 700      * @return Integer: Namespace index
 701      */
 702     public function getContentModelName() {
 703         if ( empty( $this->mContentModelName ) ) {
 704             $this->mContentModelName = ContentHandler::getDefaultModelFor( $this );
 705         }
 706
 707         return $this->mContentModelName;
 708     }
 709
 710     /**
 711      * Conveniance method for checking a title's content model name
 712      *
 713      * @param $name
 714      * @return true if $this->getContentModelName() == $name
 715      */
 716     public function hasContentModel( $name ) {
 717         return $this->getContentModelName() == $name;
 718     }
 719
 720         /**
 721          * Get the namespace text
 722          *
 723          * @return String: Namespace text
 724          */
 725         public function getNsText() {
 726                 global $wgContLang;
 727
 728                 if ( $this->mInterwiki != '' ) {
 729                         // This probably shouldn't even happen. ohh man, oh yuck.
 730                         // But for interwiki transclusion it sometimes does.
 731                         // Shit. Shit shit shit.
 732                         //
 733                         // Use the canonical namespaces if possible to try to
 734                         // resolve a foreign namespace.
 735                         if ( MWNamespace::exists( $this->mNamespace ) ) {
 736                                 return MWNamespace::getCanonicalName( $this->mNamespace );
 737                         }
 738                 }
 739
 740                 // Strip off subpages
 741                 $pagename = $this->getText();
 742                 if ( strpos( $pagename, '/' ) !== false ) {
 743                         list( $username , ) = explode( '/', $pagename, 2 );
 744                 } else {
 745                         $username = $pagename;
 746                 }
 747
 748                 if ( $wgContLang->needsGenderDistinction() &&
 749                                 MWNamespace::hasGenderDistinction( $this->mNamespace ) ) {
 750                         $gender = GenderCache::singleton()->getGenderOf( $username, __METHOD__ );
 751                         return $wgContLang->getGenderNsText( $this->mNamespace, $gender );
 752                 }
 753
 754                 return $wgContLang->getNsText( $this->mNamespace );
 755         }
 756
 757         /**
 758          * Get the namespace text of the subject (rather than talk) page
 759          *
 760          * @return String Namespace text
 761          */
 762         public function getSubjectNsText() {
 763                 global $wgContLang;
 764                 return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
 765         }
 766
 767         /**
 768          * Get the namespace text of the talk page
 769          *
 770          * @return String Namespace text
 771          */
 772         public function getTalkNsText() {
 773                 global $wgContLang;
 774                 return( $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) ) );
 775         }
 776
 777         /**
 778          * Could this title have a corresponding talk page?
 779          *
 780          * @return Bool TRUE or FALSE
 781          */
 782         public function canTalk() {
 783                 return( MWNamespace::canTalk( $this->mNamespace ) );
 784         }
 785
 786         /**
 787          * Is this in a namespace that allows actual pages?
 788          *
 789          * @return Bool
 790          * @internal note -- uses hardcoded namespace index instead of constants
 791          */
 792         public function canExist() {
 793                 return $this->mNamespace >= NS_MAIN;
 794         }
 795
 796         /**
 797          * Can this title be added to a user's watchlist?
 798          *
 799          * @return Bool TRUE or FALSE
 800          */
 801         public function isWatchable() {
 802                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
 803         }
 804
 805         /**
 806          * Returns true if this is a special page.
 807          *
 808          * @return boolean
 809          */
 810         public function isSpecialPage() {
 811                 return $this->getNamespace() == NS_SPECIAL;
 812         }
 813
 814         /**
 815          * Returns true if this title resolves to the named special page
 816          *
 817          * @param $name String The special page name
 818          * @return boolean
 819          */
 820         public function isSpecial( $name ) {
 821                 if ( $this->isSpecialPage() ) {
 822                         list( $thisName, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $this->getDBkey() );
 823                         if ( $name == $thisName ) {
 824                                 return true;
 825                         }
 826                 }
 827                 return false;
 828         }
 829
 830         /**
 831          * If the Title refers to a special page alias which is not the local default, resolve
 832          * the alias, and localise the name as necessary.  Otherwise, return $this
 833          *
 834          * @return Title
 835          */
 836         public function fixSpecialName() {
 837                 if ( $this->isSpecialPage() ) {
 838                         list( $canonicalName, $par ) = SpecialPageFactory::resolveAlias( $this->mDbkeyform );
 839                         if ( $canonicalName ) {
 840                                 $localName = SpecialPageFactory::getLocalNameFor( $canonicalName, $par );
 841                                 if ( $localName != $this->mDbkeyform ) {
 842                                         return Title::makeTitle( NS_SPECIAL, $localName );
 843                                 }
 844                         }
 845                 }
 846                 return $this;
 847         }
 848
 849         /**
 850          * Returns true if the title is inside the specified namespace.
 851          *
 852          * Please make use of this instead of comparing to getNamespace()
 853          * This function is much more resistant to changes we may make
 854          * to namespaces than code that makes direct comparisons.
 855          * @param $ns int The namespace
 856          * @return bool
 857          * @since 1.19
 858          */
 859         public function inNamespace( $ns ) {
 860                 return MWNamespace::equals( $this->getNamespace(), $ns );
 861         }
 862
 863         /**
 864          * Returns true if the title is inside one of the specified namespaces.
 865          *
 866          * @param ...$namespaces The namespaces to check for
 867          * @return bool
 868          * @since 1.19
 869          */
 870         public function inNamespaces( /* ... */ ) {
 871                 $namespaces = func_get_args();
 872                 if ( count( $namespaces ) > 0 && is_array( $namespaces[0] ) ) {
 873                         $namespaces = $namespaces[0];
 874                 }
 875
 876                 foreach ( $namespaces as $ns ) {
 877                         if ( $this->inNamespace( $ns ) ) {
 878                                 return true;
 879                         }
 880                 }
 881
 882                 return false;
 883         }
 884
 885         /**
 886          * Returns true if the title has the same subject namespace as the
 887          * namespace specified.
 888          * For example this method will take NS_USER and return true if namespace
 889          * is either NS_USER or NS_USER_TALK since both of them have NS_USER
 890          * as their subject namespace.
 891          *
 892          * This is MUCH simpler than individually testing for equivilance
 893          * against both NS_USER and NS_USER_TALK, and is also forward compatible.
 894          * @since 1.19
 895          */
 896         public function hasSubjectNamespace( $ns ) {
 897                 return MWNamespace::subjectEquals( $this->getNamespace(), $ns );
 898         }
 899
 900         /**
 901          * Is this Title in a namespace which contains content?
 902          * In other words, is this a content page, for the purposes of calculating
 903          * statistics, etc?
 904          *
 905          * @return Boolean
 906          */
 907         public function isContentPage() {
 908                 return MWNamespace::isContent( $this->getNamespace() );
 909         }
 910
 911         /**
 912          * Would anybody with sufficient privileges be able to move this page?
 913          * Some pages just aren't movable.
 914          *
 915          * @return Bool TRUE or FALSE
 916          */
 917         public function isMovable() {
 918                 if ( !MWNamespace::isMovable( $this->getNamespace() ) || $this->getInterwiki() != '' ) {
 919                         // Interwiki title or immovable namespace. Hooks don't get to override here
 920                         return false;
 921                 }
 922
 923                 $result = true;
 924                 wfRunHooks( 'TitleIsMovable', array( $this, &$result ) );
 925                 return $result;
 926         }
 927
 928         /**
 929          * Is this the mainpage?
 930          * @note Title::newFromText seams to be sufficiently optimized by the title
 931          * cache that we don't need to over-optimize by doing direct comparisons and
 932          * acidentally creating new bugs where $title->equals( Title::newFromText() )
 933          * ends up reporting something differently than $title->isMainPage();
 934          *
 935          * @since 1.18
 936          * @return Bool
 937          */
 938         public function isMainPage() {
 939                 return $this->equals( Title::newMainPage() );
 940         }
 941
 942         /**
 943          * Is this a subpage?
 944          *
 945          * @return Bool
 946          */
 947         public function isSubpage() {
 948                 return MWNamespace::hasSubpages( $this->mNamespace )
 949                         ? strpos( $this->getText(), '/' ) !== false
 950                         : false;
 951         }
 952
 953         /**
 954          * Is this a conversion table for the LanguageConverter?
 955          *
 956          * @return Bool
 957          */
 958         public function isConversionTable() {
 959                 return $this->getNamespace() == NS_MEDIAWIKI &&
 960                         strpos( $this->getText(), 'Conversiontable' ) !== false;
 961         }
 962
 963         /**
 964          * Does that page contain wikitext, or it is JS, CSS or whatever?
 965          *
 966          * @return Bool
 967          */
 968         public function isWikitextPage() {
 969                 return $this->hasContentModel( CONTENT_MODEL_WIKITEXT );
 970         }
 971
 972         /**
 973          * Could this page contain custom CSS or JavaScript for the global UI.
 974      * This is generally true for pages in the MediaWiki namespace having CONTENT_MODEL_CSS
 975      * or CONTENT_MODEL_JAVASCRIPT.
 976      *
 977      * Note that this method should not return true for pages that contain and show "inactive" CSS or JS.
 978          *
 979          * @return Bool
 980          */
 981         public function isCssOrJsPage() {
 982         $isCssOrJsPage = NS_MEDIAWIKI == $this->mNamespace
 983             && ( $this->hasContentModel( CONTENT_MODEL_CSS )
 984                 || $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
 985
 986         #NOTE: this hook is also called in ContentHandler::getDefaultModel. It's called here again to make sure
 987         #      hook funktions can force this method to return true even outside the mediawiki namespace.
 988
 989         wfRunHooks( 'TitleIsCssOrJsPage', array( $this, &$isCssOrJsPage ) );
 990
 991         return $isCssOrJsPage;
 992         }
 993
 994         /**
 995          * Is this a .css or .js subpage of a user page?
 996          * @return Bool
 997          */
 998         public function isCssJsSubpage() {
 999                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
1000             && $this->isCssOrJsPage() );
1001         }
1002
1003         /**
1004          * Trim down a .css or .js subpage title to get the corresponding skin name
1005          *
1006          * @return string containing skin name from .css or .js subpage title
1007          */
1008         public function getSkinFromCssJsSubpage() {
1009                 $subpage = explode( '/', $this->mTextform );
1010                 $subpage = $subpage[ count( $subpage ) - 1 ];
1011                 $lastdot = strrpos( $subpage, '.' );
1012                 if ( $lastdot === false )
1013                         return $subpage; # Never happens: only called for names ending in '.css' or '.js'
1014                 return substr( $subpage, 0, $lastdot );
1015         }
1016
1017         /**
1018          * Is this a .css subpage of a user page?
1019          *
1020          * @return Bool
1021          */
1022         public function isCssSubpage() {
1023         return ( NS_USER == $this->mNamespace && $this->isSubpage()
1024             && $this->hasContentModel( CONTENT_MODEL_CSS ) );
1025         }
1026
1027         /**
1028          * Is this a .js subpage of a user page?
1029          *
1030          * @return Bool
1031          */
1032         public function isJsSubpage() {
1033         return ( NS_USER == $this->mNamespace && $this->isSubpage()
1034             && $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
1035         }
1036
1037         /**
1038          * Is this a talk page of some sort?
1039          *
1040          * @return Bool
1041          */
1042         public function isTalkPage() {
1043                 return MWNamespace::isTalk( $this->getNamespace() );
1044         }
1045
1046         /**
1047          * Get a Title object associated with the talk page of this article
1048          *
1049          * @return Title the object for the talk page
1050          */
1051         public function getTalkPage() {
1052                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1053         }
1054
1055         /**
1056          * Get a title object associated with the subject page of this
1057          * talk page
1058          *
1059          * @return Title the object for the subject page
1060          */
1061         public function getSubjectPage() {
1062                 // Is this the same title?
1063                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
1064                 if ( $this->getNamespace() == $subjectNS ) {
1065                         return $this;
1066                 }
1067                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
1068         }
1069
1070         /**
1071          * Get the default namespace index, for when there is no namespace
1072          *
1073          * @return Int Default namespace index
1074          */
1075         public function getDefaultNamespace() {
1076                 return $this->mDefaultNamespace;
1077         }
1078
1079         /**
1080          * Get title for search index
1081          *
1082          * @return String a stripped-down title string ready for the
1083          *  search index
1084          */
1085         public function getIndexTitle() {
1086                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
1087         }
1088
1089         /**
1090          * Get the Title fragment (i.e.\ the bit after the #) in text form
1091          *
1092          * @return String Title fragment
1093          */
1094         public function getFragment() {
1095                 return $this->mFragment;
1096         }
1097
1098         /**
1099          * Get the fragment in URL form, including the "#" character if there is one
1100          * @return String Fragment in URL form
1101          */
1102         public function getFragmentForURL() {
1103                 if ( $this->mFragment == '' ) {
1104                         return '';
1105                 } else {
1106                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
1107                 }
1108         }
1109
1110         /**
1111          * Set the fragment for this title. Removes the first character from the
1112          * specified fragment before setting, so it assumes you're passing it with
1113          * an initial "#".
1114          *
1115          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
1116          * Still in active use privately.
1117          *
1118          * @param $fragment String text
1119          */
1120         public function setFragment( $fragment ) {
1121                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
1122         }
1123
1124         /**
1125          * Prefix some arbitrary text with the namespace or interwiki prefix
1126          * of this object
1127          *
1128          * @param $name String the text
1129          * @return String the prefixed text
1130          * @private
1131          */
1132         private function prefix( $name ) {
1133                 $p = '';
1134                 if ( $this->mInterwiki != '' ) {
1135                         $p = $this->mInterwiki . ':';
1136                 }
1137
1138                 if ( 0 != $this->mNamespace ) {
1139                         $p .= $this->getNsText() . ':';
1140                 }
1141                 return $p . $name;
1142         }
1143
1144         /**
1145          * Get the prefixed database key form
1146          *
1147          * @return String the prefixed title, with underscores and
1148          *  any interwiki and namespace prefixes
1149          */
1150         public function getPrefixedDBkey() {
1151                 $s = $this->prefix( $this->mDbkeyform );
1152                 $s = str_replace( ' ', '_', $s );
1153                 return $s;
1154         }
1155
1156         /**
1157          * Get the prefixed title with spaces.
1158          * This is the form usually used for display
1159          *
1160          * @return String the prefixed title, with spaces
1161          */
1162         public function getPrefixedText() {
1163                 // @todo FIXME: Bad usage of empty() ?
1164                 if ( empty( $this->mPrefixedText ) ) {
1165                         $s = $this->prefix( $this->mTextform );
1166                         $s = str_replace( '_', ' ', $s );
1167                         $this->mPrefixedText = $s;
1168                 }
1169                 return $this->mPrefixedText;
1170         }
1171
1172         /**
1173          * Return a string representation of this title
1174          *
1175          * @return String representation of this title
1176          */
1177         public function __toString() {
1178                 return $this->getPrefixedText();
1179         }
1180
1181         /**
1182          * Get the prefixed title with spaces, plus any fragment
1183          * (part beginning with '#')
1184          *
1185          * @return String the prefixed title, with spaces and the fragment, including '#'
1186          */
1187         public function getFullText() {
1188                 $text = $this->getPrefixedText();
1189                 if ( $this->mFragment != '' ) {
1190                         $text .= '#' . $this->mFragment;
1191                 }
1192                 return $text;
1193         }
1194
1195         /**
1196          * Get the base page name, i.e. the leftmost part before any slashes
1197          *
1198          * @return String Base name
1199          */
1200         public function getBaseText() {
1201                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1202                         return $this->getText();
1203                 }
1204
1205                 $parts = explode( '/', $this->getText() );
1206                 # Don't discard the real title if there's no subpage involved
1207                 if ( count( $parts ) > 1 ) {
1208                         unset( $parts[count( $parts ) - 1] );
1209                 }
1210                 return implode( '/', $parts );
1211         }
1212
1213         /**
1214          * Get the lowest-level subpage name, i.e. the rightmost part after any slashes
1215          *
1216          * @return String Subpage name
1217          */
1218         public function getSubpageText() {
1219                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1220                         return( $this->mTextform );
1221                 }
1222                 $parts = explode( '/', $this->mTextform );
1223                 return( $parts[count( $parts ) - 1] );
1224         }
1225
1226         /**
1227          * Get the HTML-escaped displayable text form.
1228          * Used for the title field in <a> tags.
1229          *
1230          * @return String the text, including any prefixes
1231          */
1232         public function getEscapedText() {
1233                 wfDeprecated( __METHOD__, '1.19' );
1234                 return htmlspecialchars( $this->getPrefixedText() );
1235         }
1236
1237         /**
1238          * Get a URL-encoded form of the subpage text
1239          *
1240          * @return String URL-encoded subpage name
1241          */
1242         public function getSubpageUrlForm() {
1243                 $text = $this->getSubpageText();
1244                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
1245                 return( $text );
1246         }
1247
1248         /**
1249          * Get a URL-encoded title (not an actual URL) including interwiki
1250          *
1251          * @return String the URL-encoded form
1252          */
1253         public function getPrefixedURL() {
1254                 $s = $this->prefix( $this->mDbkeyform );
1255                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
1256                 return $s;
1257         }
1258
1259         /**
1260          * Helper to fix up the get{Local,Full,Link,Canonical}URL args
1261          * get{Canonical,Full,Link,Local}URL methods accepted an optional
1262          * second argument named variant. This was deprecated in favor
1263          * of passing an array of option with a "variant" key
1264          * Once $query2 is removed for good, this helper can be dropped
1265          * andthe wfArrayToCGI moved to getLocalURL();
1266          *
1267          * @since 1.19 (r105919)
1268          */
1269         private static function fixUrlQueryArgs( $query, $query2 = false ) {
1270                 if( $query2 !== false ) {
1271                         wfDeprecated( "Title::get{Canonical,Full,Link,Local} method called with a second parameter is deprecated. Add your parameter to an array passed as the first parameter.", "1.19" );
1272                 }
1273                 if ( is_array( $query ) ) {
1274                         $query = wfArrayToCGI( $query );
1275                 }
1276                 if ( $query2 ) {
1277                         if ( is_string( $query2 ) ) {
1278                                 // $query2 is a string, we will consider this to be
1279                                 // a deprecated $variant argument and add it to the query
1280                                 $query2 = wfArrayToCGI( array( 'variant' => $query2 ) );
1281                         } else {
1282                                 $query2 = wfArrayToCGI( $query2 );
1283                         }
1284                         // If we have $query content add a & to it first
1285                         if ( $query ) {
1286                                 $query .= '&';
1287                         }
1288                         // Now append the queries together
1289                         $query .= $query2;
1290                 }
1291                 return $query;
1292         }
1293
1294         /**
1295          * Get a real URL referring to this title, with interwiki link and
1296          * fragment
1297          *
1298          * See getLocalURL for the arguments.
1299          *
1300          * @see self::getLocalURL
1301          * @return String the URL
1302          */
1303         public function getFullURL( $query = '', $query2 = false ) {
1304                 $query = self::fixUrlQueryArgs( $query, $query2 );
1305
1306                 # Hand off all the decisions on urls to getLocalURL
1307                 $url = $this->getLocalURL( $query );
1308
1309                 # Expand the url to make it a full url. Note that getLocalURL has the
1310                 # potential to output full urls for a variety of reasons, so we use
1311                 # wfExpandUrl instead of simply prepending $wgServer
1312                 $url = wfExpandUrl( $url, PROTO_RELATIVE );
1313
1314                 # Finally, add the fragment.
1315                 $url .= $this->getFragmentForURL();
1316
1317                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
1318                 return $url;
1319         }
1320
1321         /**
1322          * Get a URL with no fragment or server name.  If this page is generated
1323          * with action=render, $wgServer is prepended.
1324          *
1325
1326          * @param $query \twotypes{\string,\array} an optional query string,
1327          *   not used for interwiki     links. Can be specified as an associative array as well,
1328          *   e.g., array( 'action' => 'edit' ) (keys and values will be URL-escaped).
1329          *   Some query patterns will trigger various shorturl path replacements.
1330          * @param $query2 Mixed: An optional secondary query array. This one MUST
1331          *   be an array. If a string is passed it will be interpreted as a deprecated
1332          *   variant argument and urlencoded into a variant= argument.
1333          *   This second query argument will be added to the $query
1334          *   The second parameter is deprecated since 1.19. Pass it as a key,value
1335          *   pair in the first parameter array instead.
1336          *
1337          * @return String the URL
1338          */
1339         public function getLocalURL( $query = '', $query2 = false ) {
1340                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
1341
1342                 $query = self::fixUrlQueryArgs( $query, $query2 );
1343
1344                 $interwiki = Interwiki::fetch( $this->mInterwiki );
1345                 if ( $interwiki ) {
1346                         $namespace = $this->getNsText();
1347                         if ( $namespace != '' ) {
1348                                 # Can this actually happen? Interwikis shouldn't be parsed.
1349                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
1350                                 $namespace .= ':';
1351                         }
1352                         $url = $interwiki->getURL( $namespace . $this->getDBkey() );
1353                         $url = wfAppendQuery( $url, $query );
1354                 } else {
1355                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
1356                         if ( $query == '' ) {
1357                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
1358                                 wfRunHooks( 'GetLocalURL::Article', array( &$this, &$url ) );
1359                         } else {
1360                                 global $wgVariantArticlePath, $wgActionPaths;
1361                                 $url = false;
1362                                 $matches = array();
1363
1364                                 if ( !empty( $wgActionPaths ) &&
1365                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
1366                                 {
1367                                         $action = urldecode( $matches[2] );
1368                                         if ( isset( $wgActionPaths[$action] ) ) {
1369                                                 $query = $matches[1];
1370                                                 if ( isset( $matches[4] ) ) {
1371                                                         $query .= $matches[4];
1372                                                 }
1373                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
1374                                                 if ( $query != '' ) {
1375                                                         $url = wfAppendQuery( $url, $query );
1376                                                 }
1377                                         }
1378                                 }
1379
1380                                 if ( $url === false &&
1381                                         $wgVariantArticlePath &&
1382                                         $this->getPageLanguage()->hasVariants() &&
1383                                         preg_match( '/^variant=([^&]*)$/', $query, $matches ) )
1384                                 {
1385                                         $variant = urldecode( $matches[1] );
1386                                         if ( $this->getPageLanguage()->hasVariant( $variant ) ) {
1387                                                 // Only do the variant replacement if the given variant is a valid
1388                                                 // variant for the page's language.
1389                                                 $url = str_replace( '$2', urlencode( $variant ), $wgVariantArticlePath );
1390                                                 $url = str_replace( '$1', $dbkey, $url );
1391                                         }
1392                                 }
1393
1394                                 if ( $url === false ) {
1395                                         if ( $query == '-' ) {
1396                                                 $query = '';
1397                                         }
1398                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
1399                                 }
1400                         }
1401
1402                         wfRunHooks( 'GetLocalURL::Internal', array( &$this, &$url, $query ) );
1403
1404                         // @todo FIXME: This causes breakage in various places when we
1405                         // actually expected a local URL and end up with dupe prefixes.
1406                         if ( $wgRequest->getVal( 'action' ) == 'render' ) {
1407                                 $url = $wgServer . $url;
1408                         }
1409                 }
1410                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
1411                 return $url;
1412         }
1413
1414         /**
1415          * Get a URL that's the simplest URL that will be valid to link, locally,
1416          * to the current Title.  It includes the fragment, but does not include
1417          * the server unless action=render is used (or the link is external).  If
1418          * there's a fragment but the prefixed text is empty, we just return a link
1419          * to the fragment.
1420          *
1421          * The result obviously should not be URL-escaped, but does need to be
1422          * HTML-escaped if it's being output in HTML.
1423          *
1424          * See getLocalURL for the arguments.
1425          *
1426          * @see self::getLocalURL
1427          * @return String the URL
1428          */
1429         public function getLinkURL( $query = '', $query2 = false ) {
1430                 wfProfileIn( __METHOD__ );
1431                 if ( $this->isExternal() ) {
1432                         $ret = $this->getFullURL( $query, $query2 );
1433                 } elseif ( $this->getPrefixedText() === '' && $this->getFragment() !== '' ) {
1434                         $ret = $this->getFragmentForURL();
1435                 } else {
1436                         $ret = $this->getLocalURL( $query, $query2 ) . $this->getFragmentForURL();
1437                 }
1438                 wfProfileOut( __METHOD__ );
1439                 return $ret;
1440         }
1441
1442         /**
1443          * Get an HTML-escaped version of the URL form, suitable for
1444          * using in a link, without a server name or fragment
1445          *
1446          * See getLocalURL for the arguments.
1447          *
1448          * @see self::getLocalURL
1449          * @return String the URL
1450          */
1451         public function escapeLocalURL( $query = '', $query2 = false ) {
1452                 wfDeprecated( __METHOD__, '1.19' );
1453                 return htmlspecialchars( $this->getLocalURL( $query, $query2 ) );
1454         }
1455
1456         /**
1457          * Get an HTML-escaped version of the URL form, suitable for
1458          * using in a link, including the server name and fragment
1459          *
1460          * See getLocalURL for the arguments.
1461          *
1462          * @see self::getLocalURL
1463          * @return String the URL
1464          */
1465         public function escapeFullURL( $query = '', $query2 = false ) {
1466                 wfDeprecated( __METHOD__, '1.19' );
1467                 return htmlspecialchars( $this->getFullURL( $query, $query2 ) );
1468         }
1469
1470         /**
1471          * Get the URL form for an internal link.
1472          * - Used in various Squid-related code, in case we have a different
1473          * internal hostname for the server from the exposed one.
1474          *
1475          * This uses $wgInternalServer to qualify the path, or $wgServer
1476          * if $wgInternalServer is not set. If the server variable used is
1477          * protocol-relative, the URL will be expanded to http://
1478          *
1479          * See getLocalURL for the arguments.
1480          *
1481          * @see self::getLocalURL
1482          * @return String the URL
1483          */
1484         public function getInternalURL( $query = '', $query2 = false ) {
1485                 global $wgInternalServer, $wgServer;
1486                 $query = self::fixUrlQueryArgs( $query, $query2 );
1487                 $server = $wgInternalServer !== false ? $wgInternalServer : $wgServer;
1488                 $url = wfExpandUrl( $server . $this->getLocalURL( $query ), PROTO_HTTP );
1489                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
1490                 return $url;
1491         }
1492
1493         /**
1494          * Get the URL for a canonical link, for use in things like IRC and
1495          * e-mail notifications. Uses $wgCanonicalServer and the
1496          * GetCanonicalURL hook.
1497          *
1498          * NOTE: Unlike getInternalURL(), the canonical URL includes the fragment
1499          *
1500          * See getLocalURL for the arguments.
1501          *
1502          * @see self::getLocalURL
1503          * @return string The URL
1504          * @since 1.18
1505          */
1506         public function getCanonicalURL( $query = '', $query2 = false ) {
1507                 $query = self::fixUrlQueryArgs( $query, $query2 );
1508                 $url = wfExpandUrl( $this->getLocalURL( $query ) . $this->getFragmentForURL(), PROTO_CANONICAL );
1509                 wfRunHooks( 'GetCanonicalURL', array( &$this, &$url, $query ) );
1510                 return $url;
1511         }
1512
1513         /**
1514          * HTML-escaped version of getCanonicalURL()
1515          *
1516          * See getLocalURL for the arguments.
1517          *
1518          * @see self::getLocalURL
1519          * @since 1.18
1520          */
1521         public function escapeCanonicalURL( $query = '', $query2 = false ) {
1522                 wfDeprecated( __METHOD__, '1.19' );
1523                 return htmlspecialchars( $this->getCanonicalURL( $query, $query2 ) );
1524         }
1525
1526         /**
1527          * Get the edit URL for this Title
1528          *
1529          * @return String the URL, or a null string if this is an
1530          *  interwiki link
1531          */
1532         public function getEditURL() {
1533                 if ( $this->mInterwiki != '' ) {
1534                         return '';
1535                 }
1536                 $s = $this->getLocalURL( 'action=edit' );
1537
1538                 return $s;
1539         }
1540
1541         /**
1542          * Is $wgUser watching this page?
1543          *
1544          * @return Bool
1545          */
1546         public function userIsWatching() {
1547                 global $wgUser;
1548
1549                 if ( is_null( $this->mWatched ) ) {
1550                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn() ) {
1551                                 $this->mWatched = false;
1552                         } else {
1553                                 $this->mWatched = $wgUser->isWatched( $this );
1554                         }
1555                 }
1556                 return $this->mWatched;
1557         }
1558
1559         /**
1560          * Can $wgUser read this page?
1561          *
1562          * @deprecated in 1.19; use userCan(), quickUserCan() or getUserPermissionsErrors() instead
1563          * @return Bool
1564          * @todo fold these checks into userCan()
1565          */
1566         public function userCanRead() {
1567                 wfDeprecated( __METHOD__, '1.19' );
1568                 return $this->userCan( 'read' );
1569         }
1570
1571         /**
1572          * Can $user perform $action on this page?
1573          * This skips potentially expensive cascading permission checks
1574          * as well as avoids expensive error formatting
1575          *
1576          * Suitable for use for nonessential UI controls in common cases, but
1577          * _not_ for functional access control.
1578          *
1579          * May provide false positives, but should never provide a false negative.
1580          *
1581          * @param $action String action that permission needs to be checked for
1582          * @param $user User to check (since 1.19); $wgUser will be used if not
1583          *              provided.
1584          * @return Bool
1585          */
1586         public function quickUserCan( $action, $user = null ) {
1587                 return $this->userCan( $action, $user, false );
1588         }
1589
1590         /**
1591          * Can $user perform $action on this page?
1592          *
1593          * @param $action String action that permission needs to be checked for
1594          * @param $user User to check (since 1.19); $wgUser will be used if not
1595          *   provided.
1596          * @param $doExpensiveQueries Bool Set this to false to avoid doing
1597          *   unnecessary queries.
1598          * @return Bool
1599          */
1600         public function userCan( $action, $user = null, $doExpensiveQueries = true ) {
1601                 if ( !$user instanceof User ) {
1602                         global $wgUser;
1603                         $user = $wgUser;
1604                 }
1605                 return !count( $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries, true ) );
1606         }
1607
1608         /**
1609          * Can $user perform $action on this page?
1610          *
1611          * @todo FIXME: This *does not* check throttles (User::pingLimiter()).
1612          *
1613          * @param $action String action that permission needs to be checked for
1614          * @param $user User to check
1615          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary
1616          *   queries by skipping checks for cascading protections and user blocks.
1617          * @param $ignoreErrors Array of Strings Set this to a list of message keys
1618          *   whose corresponding errors may be ignored.
1619          * @return Array of arguments to wfMsg to explain permissions problems.
1620          */
1621         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1622                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1623
1624                 // Remove the errors being ignored.
1625                 foreach ( $errors as $index => $error ) {
1626                         $error_key = is_array( $error ) ? $error[0] : $error;
1627
1628                         if ( in_array( $error_key, $ignoreErrors ) ) {
1629                                 unset( $errors[$index] );
1630                         }
1631                 }
1632
1633                 return $errors;
1634         }
1635
1636         /**
1637          * Permissions checks that fail most often, and which are easiest to test.
1638          *
1639          * @param $action String the action to check
1640          * @param $user User user to check
1641          * @param $errors Array list of current errors
1642          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1643          * @param $short Boolean short circuit on first error
1644          *
1645          * @return Array list of errors
1646          */
1647         private function checkQuickPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1648                 if ( $action == 'create' ) {
1649                         if ( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1650                                  ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1651                                 $errors[] = $user->isAnon() ? array( 'nocreatetext' ) : array( 'nocreate-loggedin' );
1652                         }
1653                 } elseif ( $action == 'move' ) {
1654                         if ( !$user->isAllowed( 'move-rootuserpages' )
1655                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1656                                 // Show user page-specific message only if the user can move other pages
1657                                 $errors[] = array( 'cant-move-user-page' );
1658                         }
1659
1660                         // Check if user is allowed to move files if it's a file
1661                         if ( $this->mNamespace == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1662                                 $errors[] = array( 'movenotallowedfile' );
1663                         }
1664
1665                         if ( !$user->isAllowed( 'move' ) ) {
1666                                 // User can't move anything
1667                                 global $wgGroupPermissions;
1668                                 $userCanMove = false;
1669                                 if ( isset( $wgGroupPermissions['user']['move'] ) ) {
1670                                         $userCanMove = $wgGroupPermissions['user']['move'];
1671                                 }
1672                                 $autoconfirmedCanMove = false;
1673                                 if ( isset( $wgGroupPermissions['autoconfirmed']['move'] ) ) {
1674                                         $autoconfirmedCanMove = $wgGroupPermissions['autoconfirmed']['move'];
1675                                 }
1676                                 if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
1677                                         // custom message if logged-in users without any special rights can move
1678                                         $errors[] = array( 'movenologintext' );
1679                                 } else {
1680                                         $errors[] = array( 'movenotallowed' );
1681                                 }
1682                         }
1683                 } elseif ( $action == 'move-target' ) {
1684                         if ( !$user->isAllowed( 'move' ) ) {
1685                                 // User can't move anything
1686                                 $errors[] = array( 'movenotallowed' );
1687                         } elseif ( !$user->isAllowed( 'move-rootuserpages' )
1688                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1689                                 // Show user page-specific message only if the user can move other pages
1690                                 $errors[] = array( 'cant-move-to-user-page' );
1691                         }
1692                 } elseif ( !$user->isAllowed( $action ) ) {
1693                         $errors[] = $this->missingPermissionError( $action, $short );
1694                 }
1695
1696                 return $errors;
1697         }
1698
1699         /**
1700          * Add the resulting error code to the errors array
1701          *
1702          * @param $errors Array list of current errors
1703          * @param $result Mixed result of errors
1704          *
1705          * @return Array list of errors
1706          */
1707         private function resultToError( $errors, $result ) {
1708                 if ( is_array( $result ) && count( $result ) && !is_array( $result[0] ) ) {
1709                         // A single array representing an error
1710                         $errors[] = $result;
1711                 } elseif ( is_array( $result ) && is_array( $result[0] ) ) {
1712                         // A nested array representing multiple errors
1713                         $errors = array_merge( $errors, $result );
1714                 } elseif ( $result !== '' && is_string( $result ) ) {
1715                         // A string representing a message-id
1716                         $errors[] = array( $result );
1717                 } elseif ( $result === false ) {
1718                         // a generic "We don't want them to do that"
1719                         $errors[] = array( 'badaccess-group0' );
1720                 }
1721                 return $errors;
1722         }
1723
1724         /**
1725          * Check various permission hooks
1726          *
1727          * @param $action String the action to check
1728          * @param $user User user to check
1729          * @param $errors Array list of current errors
1730          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1731          * @param $short Boolean short circuit on first error
1732          *
1733          * @return Array list of errors
1734          */
1735         private function checkPermissionHooks( $action, $user, $errors, $doExpensiveQueries, $short ) {
1736                 // Use getUserPermissionsErrors instead
1737                 $result = '';
1738                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1739                         return $result ? array() : array( array( 'badaccess-group0' ) );
1740                 }
1741                 // Check getUserPermissionsErrors hook
1742                 if ( !wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1743                         $errors = $this->resultToError( $errors, $result );
1744                 }
1745                 // Check getUserPermissionsErrorsExpensive hook
1746                 if ( $doExpensiveQueries && !( $short && count( $errors ) > 0 ) &&
1747                          !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) ) ) {
1748                         $errors = $this->resultToError( $errors, $result );
1749                 }
1750
1751                 return $errors;
1752         }
1753
1754         /**
1755          * Check permissions on special pages & namespaces
1756          *
1757          * @param $action String the action to check
1758          * @param $user User user to check
1759          * @param $errors Array list of current errors
1760          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1761          * @param $short Boolean short circuit on first error
1762          *
1763          * @return Array list of errors
1764          */
1765         private function checkSpecialsAndNSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1766                 # Only 'createaccount' and 'execute' can be performed on
1767                 # special pages, which don't actually exist in the DB.
1768                 $specialOKActions = array( 'createaccount', 'execute', 'read' );
1769                 if ( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions ) ) {
1770                         $errors[] = array( 'ns-specialprotected' );
1771                 }
1772
1773                 # Check $wgNamespaceProtection for restricted namespaces
1774                 if ( $this->isNamespaceProtected( $user ) ) {
1775                         $ns = $this->mNamespace == NS_MAIN ?
1776                                 wfMsg( 'nstab-main' ) : $this->getNsText();
1777                         $errors[] = $this->mNamespace == NS_MEDIAWIKI ?
1778                                 array( 'protectedinterface' ) : array( 'namespaceprotected',  $ns );
1779                 }
1780
1781                 return $errors;
1782         }
1783
1784         /**
1785          * Check CSS/JS sub-page permissions
1786          *
1787          * @param $action String the action to check
1788          * @param $user User user to check
1789          * @param $errors Array list of current errors
1790          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1791          * @param $short Boolean short circuit on first error
1792          *
1793          * @return Array list of errors
1794          */
1795         private function checkCSSandJSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1796                 # Protect css/js subpages of user pages
1797                 # XXX: this might be better using restrictions
1798                 # XXX: right 'editusercssjs' is deprecated, for backward compatibility only
1799                 if ( $action != 'patrol' && !$user->isAllowed( 'editusercssjs' )
1800                                 && !preg_match( '/^' . preg_quote( $user->getName(), '/' ) . '\//', $this->mTextform ) ) {
1801                         if ( $this->isCssSubpage() && !$user->isAllowed( 'editusercss' ) ) {
1802                                 $errors[] = array( 'customcssprotected' );
1803                         } elseif ( $this->isJsSubpage() && !$user->isAllowed( 'edituserjs' ) ) {
1804                                 $errors[] = array( 'customjsprotected' );
1805                         }
1806                 }
1807
1808                 return $errors;
1809         }
1810
1811         /**
1812          * Check against page_restrictions table requirements on this
1813          * page. The user must possess all required rights for this
1814          * action.
1815          *
1816          * @param $action String the action to check
1817          * @param $user User user to check
1818          * @param $errors Array list of current errors
1819          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1820          * @param $short Boolean short circuit on first error
1821          *
1822          * @return Array list of errors
1823          */
1824         private function checkPageRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1825                 foreach ( $this->getRestrictions( $action ) as $right ) {
1826                         // Backwards compatibility, rewrite sysop -> protect
1827                         if ( $right == 'sysop' ) {
1828                                 $right = 'protect';
1829                         }
1830                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1831                                 // Users with 'editprotected' permission can edit protected pages
1832                                 // without cascading option turned on.
1833                                 if ( $action != 'edit' || !$user->isAllowed( 'editprotected' )
1834                                         || $this->mCascadeRestriction )
1835                                 {
1836                                         $errors[] = array( 'protectedpagetext', $right );
1837                                 }
1838                         }
1839                 }
1840
1841                 return $errors;
1842         }
1843
1844         /**
1845          * Check restrictions on cascading pages.
1846          *
1847          * @param $action String the action to check
1848          * @param $user User to check
1849          * @param $errors Array list of current errors
1850          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1851          * @param $short Boolean short circuit on first error
1852          *
1853          * @return Array list of errors
1854          */
1855         private function checkCascadingSourcesRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1856                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1857                         # We /could/ use the protection level on the source page, but it's
1858                         # fairly ugly as we have to establish a precedence hierarchy for pages
1859                         # included by multiple cascade-protected pages. So just restrict
1860                         # it to people with 'protect' permission, as they could remove the
1861                         # protection anyway.
1862                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1863                         # Cascading protection depends on more than this page...
1864                         # Several cascading protected pages may include this page...
1865                         # Check each cascading level
1866                         # This is only for protection restrictions, not for all actions
1867                         if ( isset( $restrictions[$action] ) ) {
1868                                 foreach ( $restrictions[$action] as $right ) {
1869                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1870                                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1871                                                 $pages = '';
1872                                                 foreach ( $cascadingSources as $page )
1873                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1874                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1875                                         }
1876                                 }
1877                         }
1878                 }
1879
1880                 return $errors;
1881         }
1882
1883         /**
1884          * Check action permissions not already checked in checkQuickPermissions
1885          *
1886          * @param $action String the action to check
1887          * @param $user User to check
1888          * @param $errors Array list of current errors
1889          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1890          * @param $short Boolean short circuit on first error
1891          *
1892          * @return Array list of errors
1893          */
1894         private function checkActionPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1895                 global $wgDeleteRevisionsLimit, $wgLang;
1896
1897                 if ( $action == 'protect' ) {
1898                         if ( count( $this->getUserPermissionsErrorsInternal( 'edit', $user, $doExpensiveQueries, true ) ) ) {
1899                                 // If they can't edit, they shouldn't protect.
1900                                 $errors[] = array( 'protect-cantedit' );
1901                         }
1902                 } elseif ( $action == 'create' ) {
1903                         $title_protection = $this->getTitleProtection();
1904                         if( $title_protection ) {
1905                                 if( $title_protection['pt_create_perm'] == 'sysop' ) {
1906                                         $title_protection['pt_create_perm'] = 'protect'; // B/C
1907                                 }
1908                                 if( $title_protection['pt_create_perm'] == '' ||
1909                                         !$user->isAllowed( $title_protection['pt_create_perm'] ) )
1910                                 {
1911                                         $errors[] = array( 'titleprotected', User::whoIs( $title_protection['pt_user'] ), $title_protection['pt_reason'] );
1912                                 }
1913                         }
1914                 } elseif ( $action == 'move' ) {
1915                         // Check for immobile pages
1916                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1917                                 // Specific message for this case
1918                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1919                         } elseif ( !$this->isMovable() ) {
1920                                 // Less specific message for rarer cases
1921                                 $errors[] = array( 'immobile-source-page' );
1922                         }
1923                 } elseif ( $action == 'move-target' ) {
1924                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1925                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1926                         } elseif ( !$this->isMovable() ) {
1927                                 $errors[] = array( 'immobile-target-page' );
1928                         }
1929                 } elseif ( $action == 'delete' ) {
1930                         if ( $doExpensiveQueries && $wgDeleteRevisionsLimit
1931                                 && !$this->userCan( 'bigdelete', $user ) && $this->isBigDeletion() )
1932                         {
1933                                 $errors[] = array( 'delete-toobig', $wgLang->formatNum( $wgDeleteRevisionsLimit ) );
1934                         }
1935                 }
1936                 return $errors;
1937         }
1938
1939         /**
1940          * Check that the user isn't blocked from editting.
1941          *
1942          * @param $action String the action to check
1943          * @param $user User to check
1944          * @param $errors Array list of current errors
1945          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1946          * @param $short Boolean short circuit on first error
1947          *
1948          * @return Array list of errors
1949          */
1950         private function checkUserBlock( $action, $user, $errors, $doExpensiveQueries, $short ) {
1951                 // Account creation blocks handled at userlogin.
1952                 // Unblocking handled in SpecialUnblock
1953                 if( !$doExpensiveQueries || in_array( $action, array( 'createaccount', 'unblock' ) ) ) {
1954                         return $errors;
1955                 }
1956
1957                 global $wgContLang, $wgLang, $wgEmailConfirmToEdit;
1958
1959                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() ) {
1960                         $errors[] = array( 'confirmedittext' );
1961                 }
1962
1963                 if ( ( $action == 'edit' || $action == 'create' ) && !$user->isBlockedFrom( $this ) ) {
1964                         // Don't block the user from editing their own talk page unless they've been
1965                         // explicitly blocked from that too.
1966                 } elseif( $user->isBlocked() && $user->mBlock->prevents( $action ) !== false ) {
1967                         $block = $user->mBlock;
1968
1969                         // This is from OutputPage::blockedPage
1970                         // Copied at r23888 by werdna
1971
1972                         $id = $user->blockedBy();
1973                         $reason = $user->blockedFor();
1974                         if ( $reason == '' ) {
1975                                 $reason = wfMsg( 'blockednoreason' );
1976                         }
1977                         $ip = $user->getRequest()->getIP();
1978
1979                         if ( is_numeric( $id ) ) {
1980                                 $name = User::whoIs( $id );
1981                         } else {
1982                                 $name = $id;
1983                         }
1984
1985                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1986                         $blockid = $block->getId();
1987                         $blockExpiry = $user->mBlock->mExpiry;
1988                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $user->mBlock->mTimestamp ), true );
1989                         if ( $blockExpiry == 'infinity' ) {
1990                                 $blockExpiry = wfMessage( 'infiniteblock' )->text();
1991                         } else {
1992                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1993                         }
1994
1995                         $intended = strval( $user->mBlock->getTarget() );
1996
1997                         $errors[] = array( ( $block->mAuto ? 'autoblockedtext' : 'blockedtext' ), $link, $reason, $ip, $name,
1998                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
1999                 }
2000
2001                 return $errors;
2002         }
2003
2004         /**
2005          * Check that the user is allowed to read this page.
2006          *
2007          * @param $action String the action to check
2008          * @param $user User to check
2009          * @param $errors Array list of current errors
2010          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
2011          * @param $short Boolean short circuit on first error
2012          *
2013          * @return Array list of errors
2014          */
2015         private function checkReadPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
2016                 global $wgWhitelistRead, $wgGroupPermissions, $wgRevokePermissions;
2017                 static $useShortcut = null;
2018
2019                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
2020                 if ( is_null( $useShortcut ) ) {
2021                         $useShortcut = true;
2022                         if ( empty( $wgGroupPermissions['*']['read'] ) ) {
2023                                 # Not a public wiki, so no shortcut
2024                                 $useShortcut = false;
2025                         } elseif ( !empty( $wgRevokePermissions ) ) {
2026                                 /**
2027                                  * Iterate through each group with permissions being revoked (key not included since we don't care
2028                                  * what the group name is), then check if the read permission is being revoked. If it is, then
2029                                  * we don't use the shortcut below since the user might not be able to read, even though anon
2030                                  * reading is allowed.
2031                                  */
2032                                 foreach ( $wgRevokePermissions as $perms ) {
2033                                         if ( !empty( $perms['read'] ) ) {
2034                                                 # We might be removing the read right from the user, so no shortcut
2035                                                 $useShortcut = false;
2036                                                 break;
2037                                         }
2038                                 }
2039                         }
2040                 }
2041
2042                 $whitelisted = false;
2043                 if ( $useShortcut ) {
2044                         # Shortcut for public wikis, allows skipping quite a bit of code
2045                         $whitelisted = true;
2046                 } elseif ( $user->isAllowed( 'read' ) ) {
2047                         # If the user is allowed to read pages, he is allowed to read all pages
2048                         $whitelisted = true;
2049                 } elseif ( $this->isSpecial( 'Userlogin' )
2050                         || $this->isSpecial( 'ChangePassword' )
2051                         || $this->isSpecial( 'PasswordReset' )
2052                 ) {
2053                         # Always grant access to the login page.
2054                         # Even anons need to be able to log in.
2055                         $whitelisted = true;
2056                 } elseif ( is_array( $wgWhitelistRead ) && count( $wgWhitelistRead ) ) {
2057                         # Time to check the whitelist
2058                         # Only do these checks is there's something to check against
2059                         $name = $this->getPrefixedText();
2060                         $dbName = $this->getPrefixedDBKey();
2061
2062                         // Check with and without underscores
2063                         if ( in_array( $name, $wgWhitelistRead, true ) || in_array( $dbName, $wgWhitelistRead, true ) ) {
2064                                 # Check for explicit whitelisting
2065                                 $whitelisted = true;
2066                         } elseif ( $this->getNamespace() == NS_MAIN ) {
2067                                 # Old settings might have the title prefixed with
2068                                 # a colon for main-namespace pages
2069                                 if ( in_array( ':' . $name, $wgWhitelistRead ) ) {
2070                                         $whitelisted = true;
2071                                 }
2072                         } elseif ( $this->isSpecialPage() ) {
2073                                 # If it's a special page, ditch the subpage bit and check again
2074                                 $name = $this->getDBkey();
2075                                 list( $name, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $name );
2076                                 if ( $name !== false ) {
2077                                         $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
2078                                         if ( in_array( $pure, $wgWhitelistRead, true ) ) {
2079                                                 $whitelisted = true;
2080                                         }
2081                                 }
2082                         }
2083                 }
2084
2085                 if ( !$whitelisted ) {
2086                         # If the title is not whitelisted, give extensions a chance to do so...
2087                         wfRunHooks( 'TitleReadWhitelist', array( $this, $user, &$whitelisted ) );
2088                         if ( !$whitelisted ) {
2089                                 $errors[] = $this->missingPermissionError( $action, $short );
2090                         }
2091                 }
2092
2093                 return $errors;
2094         }
2095
2096         /**
2097          * Get a description array when the user doesn't have the right to perform
2098          * $action (i.e. when User::isAllowed() returns false)
2099          *
2100          * @param $action String the action to check
2101          * @param $short Boolean short circuit on first error
2102          * @return Array list of errors
2103          */
2104         private function missingPermissionError( $action, $short ) {
2105                 // We avoid expensive display logic for quickUserCan's and such
2106                 if ( $short ) {
2107                         return array( 'badaccess-group0' );
2108                 }
2109
2110                 $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
2111                         User::getGroupsWithPermission( $action ) );
2112
2113                 if ( count( $groups ) ) {
2114                         global $wgLang;
2115                         return array(
2116                                 'badaccess-groups',
2117                                 $wgLang->commaList( $groups ),
2118                                 count( $groups )
2119                         );
2120                 } else {
2121                         return array( 'badaccess-group0' );
2122                 }
2123         }
2124
2125         /**
2126          * Can $user perform $action on this page? This is an internal function,
2127          * which checks ONLY that previously checked by userCan (i.e. it leaves out
2128          * checks on wfReadOnly() and blocks)
2129          *
2130          * @param $action String action that permission needs to be checked for
2131          * @param $user User to check
2132          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary queries.
2133          * @param $short Bool Set this to true to stop after the first permission error.
2134          * @return Array of arrays of the arguments to wfMsg to explain permissions problems.
2135          */
2136         protected function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true, $short = false ) {
2137                 wfProfileIn( __METHOD__ );
2138
2139                 # Read has special handling
2140                 if ( $action == 'read' ) {
2141                         $checks = array(
2142                                 'checkPermissionHooks',
2143                                 'checkReadPermissions',
2144                         );
2145                 } else {
2146                         $checks = array(
2147                                 'checkQuickPermissions',
2148                                 'checkPermissionHooks',
2149                                 'checkSpecialsAndNSPermissions',
2150                                 'checkCSSandJSPermissions',
2151                                 'checkPageRestrictions',
2152                                 'checkCascadingSourcesRestrictions',
2153                                 'checkActionPermissions',
2154                                 'checkUserBlock'
2155                         );
2156                 }
2157
2158                 $errors = array();
2159                 while( count( $checks ) > 0 &&
2160                                 !( $short && count( $errors ) > 0 ) ) {
2161                         $method = array_shift( $checks );
2162                         $errors = $this->$method( $action, $user, $errors, $doExpensiveQueries, $short );
2163                 }
2164
2165                 wfProfileOut( __METHOD__ );
2166                 return $errors;
2167         }
2168
2169         /**
2170          * Protect css subpages of user pages: can $wgUser edit
2171          * this page?
2172          *
2173          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2174          * @return Bool
2175          */
2176         public function userCanEditCssSubpage() {
2177                 global $wgUser;
2178                 wfDeprecated( __METHOD__, '1.19' );
2179                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'editusercss' ) )
2180                         || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2181         }
2182
2183         /**
2184          * Protect js subpages of user pages: can $wgUser edit
2185          * this page?
2186          *
2187          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2188          * @return Bool
2189          */
2190         public function userCanEditJsSubpage() {
2191                 global $wgUser;
2192                 wfDeprecated( __METHOD__, '1.19' );
2193                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'edituserjs' ) )
2194                            || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2195         }
2196
2197         /**
2198          * Get a filtered list of all restriction types supported by this wiki.
2199          * @param bool $exists True to get all restriction types that apply to
2200          * titles that do exist, False for all restriction types that apply to
2201          * titles that do not exist
2202          * @return array
2203          */
2204         public static function getFilteredRestrictionTypes( $exists = true ) {
2205                 global $wgRestrictionTypes;
2206                 $types = $wgRestrictionTypes;
2207                 if ( $exists ) {
2208                         # Remove the create restriction for existing titles
2209                         $types = array_diff( $types, array( 'create' ) );
2210                 } else {
2211                         # Only the create and upload restrictions apply to non-existing titles
2212                         $types = array_intersect( $types, array( 'create', 'upload' ) );
2213                 }
2214                 return $types;
2215         }
2216
2217         /**
2218          * Returns restriction types for the current Title
2219          *
2220          * @return array applicable restriction types
2221          */
2222         public function getRestrictionTypes() {
2223                 if ( $this->isSpecialPage() ) {
2224                         return array();
2225                 }
2226
2227                 $types = self::getFilteredRestrictionTypes( $this->exists() );
2228
2229                 if ( $this->getNamespace() != NS_FILE ) {
2230                         # Remove the upload restriction for non-file titles
2231                         $types = array_diff( $types, array( 'upload' ) );
2232                 }
2233
2234                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
2235
2236                 wfDebug( __METHOD__ . ': applicable restrictions to [[' .
2237                         $this->getPrefixedText() . ']] are {' . implode( ',', $types ) . "}\n" );
2238
2239                 return $types;
2240         }
2241
2242         /**
2243          * Is this title subject to title protection?
2244          * Title protection is the one applied against creation of such title.
2245          *
2246          * @return Mixed An associative array representing any existent title
2247          *   protection, or false if there's none.
2248          */
2249         private function getTitleProtection() {
2250                 // Can't protect pages in special namespaces
2251                 if ( $this->getNamespace() < 0 ) {
2252                         return false;
2253                 }
2254
2255                 // Can't protect pages that exist.
2256                 if ( $this->exists() ) {
2257                         return false;
2258                 }
2259
2260                 if ( !isset( $this->mTitleProtection ) ) {
2261                         $dbr = wfGetDB( DB_SLAVE );
2262                         $res = $dbr->select( 'protected_titles', '*',
2263                                 array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2264                                 __METHOD__ );
2265
2266                         // fetchRow returns false if there are no rows.
2267                         $this->mTitleProtection = $dbr->fetchRow( $res );
2268                 }
2269                 return $this->mTitleProtection;
2270         }
2271
2272         /**
2273          * Update the title protection status
2274          *
2275          * @deprecated in 1.19; will be removed in 1.20. Use WikiPage::doUpdateRestrictions() instead.
2276          * @param $create_perm String Permission required for creation
2277          * @param $reason String Reason for protection
2278          * @param $expiry String Expiry timestamp
2279          * @return boolean true
2280          */
2281         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
2282                 wfDeprecated( __METHOD__, '1.19' );
2283
2284                 global $wgUser;
2285
2286                 $limit = array( 'create' => $create_perm );
2287                 $expiry = array( 'create' => $expiry );
2288
2289                 $page = WikiPage::factory( $this );
2290                 $status = $page->doUpdateRestrictions( $limit, $expiry, false, $reason, $wgUser );
2291
2292                 return $status->isOK();
2293         }
2294
2295         /**
2296          * Remove any title protection due to page existing
2297          */
2298         public function deleteTitleProtection() {
2299                 $dbw = wfGetDB( DB_MASTER );
2300
2301                 $dbw->delete(
2302                         'protected_titles',
2303                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2304                         __METHOD__
2305                 );
2306                 $this->mTitleProtection = false;
2307         }
2308
2309         /**
2310          * Is this page "semi-protected" - the *only* protection is autoconfirm?
2311          *
2312          * @param $action String Action to check (default: edit)
2313          * @return Bool
2314          */
2315         public function isSemiProtected( $action = 'edit' ) {
2316                 if ( $this->exists() ) {
2317                         $restrictions = $this->getRestrictions( $action );
2318                         if ( count( $restrictions ) > 0 ) {
2319                                 foreach ( $restrictions as $restriction ) {
2320                                         if ( strtolower( $restriction ) != 'autoconfirmed' ) {
2321                                                 return false;
2322                                         }
2323                                 }
2324                         } else {
2325                                 # Not protected
2326                                 return false;
2327                         }
2328                         return true;
2329                 } else {
2330                         # If it doesn't exist, it can't be protected
2331                         return false;
2332                 }
2333         }
2334
2335         /**
2336          * Does the title correspond to a protected article?
2337          *
2338          * @param $action String the action the page is protected from,
2339          * by default checks all actions.
2340          * @return Bool
2341          */
2342         public function isProtected( $action = '' ) {
2343                 global $wgRestrictionLevels;
2344
2345                 $restrictionTypes = $this->getRestrictionTypes();
2346
2347                 # Special pages have inherent protection
2348                 if( $this->isSpecialPage() ) {
2349                         return true;
2350                 }
2351
2352                 # Check regular protection levels
2353                 foreach ( $restrictionTypes as $type ) {
2354                         if ( $action == $type || $action == '' ) {
2355                                 $r = $this->getRestrictions( $type );
2356                                 foreach ( $wgRestrictionLevels as $level ) {
2357                                         if ( in_array( $level, $r ) && $level != '' ) {
2358                                                 return true;
2359                                         }
2360                                 }
2361                         }
2362                 }
2363
2364                 return false;
2365         }
2366
2367         /**
2368          * Determines if $user is unable to edit this page because it has been protected
2369          * by $wgNamespaceProtection.
2370          *
2371          * @param $user User object to check permissions
2372          * @return Bool
2373          */
2374         public function isNamespaceProtected( User $user ) {
2375                 global $wgNamespaceProtection;
2376
2377                 if ( isset( $wgNamespaceProtection[$this->mNamespace] ) ) {
2378                         foreach ( (array)$wgNamespaceProtection[$this->mNamespace] as $right ) {
2379                                 if ( $right != '' && !$user->isAllowed( $right ) ) {
2380                                         return true;
2381                                 }
2382                         }
2383                 }
2384                 return false;
2385         }
2386
2387         /**
2388          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
2389          *
2390          * @return Bool If the page is subject to cascading restrictions.
2391          */
2392         public function isCascadeProtected() {
2393                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
2394                 return ( $sources > 0 );
2395         }
2396
2397         /**
2398          * Cascading protection: Get the source of any cascading restrictions on this page.
2399          *
2400          * @param $getPages Bool Whether or not to retrieve the actual pages
2401          *        that the restrictions have come from.
2402          * @return Mixed Array of Title objects of the pages from which cascading restrictions
2403          *     have come, false for none, or true if such restrictions exist, but $getPages
2404          *     was not set.  The restriction array is an array of each type, each of which
2405          *     contains a array of unique groups.
2406          */
2407         public function getCascadeProtectionSources( $getPages = true ) {
2408                 global $wgContLang;
2409                 $pagerestrictions = array();
2410
2411                 if ( isset( $this->mCascadeSources ) && $getPages ) {
2412                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
2413                 } elseif ( isset( $this->mHasCascadingRestrictions ) && !$getPages ) {
2414                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
2415                 }
2416
2417                 wfProfileIn( __METHOD__ );
2418
2419                 $dbr = wfGetDB( DB_SLAVE );
2420
2421                 if ( $this->getNamespace() == NS_FILE ) {
2422                         $tables = array( 'imagelinks', 'page_restrictions' );
2423                         $where_clauses = array(
2424                                 'il_to' => $this->getDBkey(),
2425                                 'il_from=pr_page',
2426                                 'pr_cascade' => 1
2427                         );
2428                 } else {
2429                         $tables = array( 'templatelinks', 'page_restrictions' );
2430                         $where_clauses = array(
2431                                 'tl_namespace' => $this->getNamespace(),
2432                                 'tl_title' => $this->getDBkey(),
2433                                 'tl_from=pr_page',
2434                                 'pr_cascade' => 1
2435                         );
2436                 }
2437
2438                 if ( $getPages ) {
2439                         $cols = array( 'pr_page', 'page_namespace', 'page_title',
2440                                                    'pr_expiry', 'pr_type', 'pr_level' );
2441                         $where_clauses[] = 'page_id=pr_page';
2442                         $tables[] = 'page';
2443                 } else {
2444                         $cols = array( 'pr_expiry' );
2445                 }
2446
2447                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
2448
2449                 $sources = $getPages ? array() : false;
2450                 $now = wfTimestampNow();
2451                 $purgeExpired = false;
2452
2453                 foreach ( $res as $row ) {
2454                         $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2455                         if ( $expiry > $now ) {
2456                                 if ( $getPages ) {
2457                                         $page_id = $row->pr_page;
2458                                         $page_ns = $row->page_namespace;
2459                                         $page_title = $row->page_title;
2460                                         $sources[$page_id] = Title::makeTitle( $page_ns, $page_title );
2461                                         # Add groups needed for each restriction type if its not already there
2462                                         # Make sure this restriction type still exists
2463
2464                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
2465                                                 $pagerestrictions[$row->pr_type] = array();
2466                                         }
2467
2468                                         if ( isset( $pagerestrictions[$row->pr_type] ) &&
2469                                                  !in_array( $row->pr_level, $pagerestrictions[$row->pr_type] ) ) {
2470                                                 $pagerestrictions[$row->pr_type][] = $row->pr_level;
2471                                         }
2472                                 } else {
2473                                         $sources = true;
2474                                 }
2475                         } else {
2476                                 // Trigger lazy purge of expired restrictions from the db
2477                                 $purgeExpired = true;
2478                         }
2479                 }
2480                 if ( $purgeExpired ) {
2481                         Title::purgeExpiredRestrictions();
2482                 }
2483
2484                 if ( $getPages ) {
2485                         $this->mCascadeSources = $sources;
2486                         $this->mCascadingRestrictions = $pagerestrictions;
2487                 } else {
2488                         $this->mHasCascadingRestrictions = $sources;
2489                 }
2490
2491                 wfProfileOut( __METHOD__ );
2492                 return array( $sources, $pagerestrictions );
2493         }
2494
2495         /**
2496          * Accessor/initialisation for mRestrictions
2497          *
2498          * @param $action String action that permission needs to be checked for
2499          * @return Array of Strings the array of groups allowed to edit this article
2500          */
2501         public function getRestrictions( $action ) {
2502                 if ( !$this->mRestrictionsLoaded ) {
2503                         $this->loadRestrictions();
2504                 }
2505                 return isset( $this->mRestrictions[$action] )
2506                                 ? $this->mRestrictions[$action]
2507                                 : array();
2508         }
2509
2510         /**
2511          * Get the expiry time for the restriction against a given action
2512          *
2513          * @return String|Bool 14-char timestamp, or 'infinity' if the page is protected forever
2514          *      or not protected at all, or false if the action is not recognised.
2515          */
2516         public function getRestrictionExpiry( $action ) {
2517                 if ( !$this->mRestrictionsLoaded ) {
2518                         $this->loadRestrictions();
2519                 }
2520                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2521         }
2522
2523         /**
2524          * Returns cascading restrictions for the current article
2525          *
2526          * @return Boolean
2527          */
2528         function areRestrictionsCascading() {
2529                 if ( !$this->mRestrictionsLoaded ) {
2530                         $this->loadRestrictions();
2531                 }
2532
2533                 return $this->mCascadeRestriction;
2534         }
2535
2536         /**
2537          * Loads a string into mRestrictions array
2538          *
2539          * @param $res Resource restrictions as an SQL result.
2540          * @param $oldFashionedRestrictions String comma-separated list of page
2541          *        restrictions from page table (pre 1.10)
2542          */
2543         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
2544                 $rows = array();
2545
2546                 foreach ( $res as $row ) {
2547                         $rows[] = $row;
2548                 }
2549
2550                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
2551         }
2552
2553         /**
2554          * Compiles list of active page restrictions from both page table (pre 1.10)
2555          * and page_restrictions table for this existing page.
2556          * Public for usage by LiquidThreads.
2557          *
2558          * @param $rows array of db result objects
2559          * @param $oldFashionedRestrictions string comma-separated list of page
2560          *        restrictions from page table (pre 1.10)
2561          */
2562         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
2563                 global $wgContLang;
2564                 $dbr = wfGetDB( DB_SLAVE );
2565
2566                 $restrictionTypes = $this->getRestrictionTypes();
2567
2568                 foreach ( $restrictionTypes as $type ) {
2569                         $this->mRestrictions[$type] = array();
2570                         $this->mRestrictionsExpiry[$type] = $wgContLang->formatExpiry( '', TS_MW );
2571                 }
2572
2573                 $this->mCascadeRestriction = false;
2574
2575                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2576
2577                 if ( $oldFashionedRestrictions === null ) {
2578                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2579                                 array( 'page_id' => $this->getArticleId() ), __METHOD__ );
2580                 }
2581
2582                 if ( $oldFashionedRestrictions != '' ) {
2583
2584                         foreach ( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2585                                 $temp = explode( '=', trim( $restrict ) );
2586                                 if ( count( $temp ) == 1 ) {
2587                                         // old old format should be treated as edit/move restriction
2588                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2589                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2590                                 } else {
2591                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
2592                                 }
2593                         }
2594
2595                         $this->mOldRestrictions = true;
2596
2597                 }
2598
2599                 if ( count( $rows ) ) {
2600                         # Current system - load second to make them override.
2601                         $now = wfTimestampNow();
2602                         $purgeExpired = false;
2603
2604                         # Cycle through all the restrictions.
2605                         foreach ( $rows as $row ) {
2606
2607                                 // Don't take care of restrictions types that aren't allowed
2608                                 if ( !in_array( $row->pr_type, $restrictionTypes ) )
2609                                         continue;
2610
2611                                 // This code should be refactored, now that it's being used more generally,
2612                                 // But I don't really see any harm in leaving it in Block for now -werdna
2613                                 $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2614
2615                                 // Only apply the restrictions if they haven't expired!
2616                                 if ( !$expiry || $expiry > $now ) {
2617                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2618                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2619
2620                                         $this->mCascadeRestriction |= $row->pr_cascade;
2621                                 } else {
2622                                         // Trigger a lazy purge of expired restrictions
2623                                         $purgeExpired = true;
2624                                 }
2625                         }
2626
2627                         if ( $purgeExpired ) {
2628                                 Title::purgeExpiredRestrictions();
2629                         }
2630                 }
2631
2632                 $this->mRestrictionsLoaded = true;
2633         }
2634
2635         /**
2636          * Load restrictions from the page_restrictions table
2637          *
2638          * @param $oldFashionedRestrictions String comma-separated list of page
2639          *        restrictions from page table (pre 1.10)
2640          */
2641         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2642                 global $wgContLang;
2643                 if ( !$this->mRestrictionsLoaded ) {
2644                         if ( $this->exists() ) {
2645                                 $dbr = wfGetDB( DB_SLAVE );
2646
2647                                 $res = $dbr->select(
2648                                         'page_restrictions',
2649                                         '*',
2650                                         array( 'pr_page' => $this->getArticleId() ),
2651                                         __METHOD__
2652                                 );
2653
2654                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2655                         } else {
2656                                 $title_protection = $this->getTitleProtection();
2657
2658                                 if ( $title_protection ) {
2659                                         $now = wfTimestampNow();
2660                                         $expiry = $wgContLang->formatExpiry( $title_protection['pt_expiry'], TS_MW );
2661
2662                                         if ( !$expiry || $expiry > $now ) {
2663                                                 // Apply the restrictions
2664                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2665                                                 $this->mRestrictions['create'] = explode( ',', trim( $title_protection['pt_create_perm'] ) );
2666                                         } else { // Get rid of the old restrictions
2667                                                 Title::purgeExpiredRestrictions();
2668                                                 $this->mTitleProtection = false;
2669                                         }
2670                                 } else {
2671                                         $this->mRestrictionsExpiry['create'] = $wgContLang->formatExpiry( '', TS_MW );
2672                                 }
2673                                 $this->mRestrictionsLoaded = true;
2674                         }
2675                 }
2676         }
2677
2678         /**
2679          * Flush the protection cache in this object and force reload from the database.
2680          * This is used when updating protection from WikiPage::doUpdateRestrictions().
2681          */
2682         public function flushRestrictions() {
2683                 $this->mRestrictionsLoaded = false;
2684                 $this->mTitleProtection = null;
2685         }
2686
2687         /**
2688          * Purge expired restrictions from the page_restrictions table
2689          */
2690         static function purgeExpiredRestrictions() {
2691                 $dbw = wfGetDB( DB_MASTER );
2692                 $dbw->delete(
2693                         'page_restrictions',
2694                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2695                         __METHOD__
2696                 );
2697
2698                 $dbw->delete(
2699                         'protected_titles',
2700                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2701                         __METHOD__
2702                 );
2703         }
2704
2705         /**
2706          * Does this have subpages?  (Warning, usually requires an extra DB query.)
2707          *
2708          * @return Bool
2709          */
2710         public function hasSubpages() {
2711                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
2712                         # Duh
2713                         return false;
2714                 }
2715
2716                 # We dynamically add a member variable for the purpose of this method
2717                 # alone to cache the result.  There's no point in having it hanging
2718                 # around uninitialized in every Title object; therefore we only add it
2719                 # if needed and don't declare it statically.
2720                 if ( isset( $this->mHasSubpages ) ) {
2721                         return $this->mHasSubpages;
2722                 }
2723
2724                 $subpages = $this->getSubpages( 1 );
2725                 if ( $subpages instanceof TitleArray ) {
2726                         return $this->mHasSubpages = (bool)$subpages->count();
2727                 }
2728                 return $this->mHasSubpages = false;
2729         }
2730
2731         /**
2732          * Get all subpages of this page.
2733          *
2734          * @param $limit Int maximum number of subpages to fetch; -1 for no limit
2735          * @return mixed TitleArray, or empty array if this page's namespace
2736          *  doesn't allow subpages
2737          */
2738         public function getSubpages( $limit = -1 ) {
2739                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
2740                         return array();
2741                 }
2742
2743                 $dbr = wfGetDB( DB_SLAVE );
2744                 $conds['page_namespace'] = $this->getNamespace();
2745                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
2746                 $options = array();
2747                 if ( $limit > -1 ) {
2748                         $options['LIMIT'] = $limit;
2749                 }
2750                 return $this->mSubpages = TitleArray::newFromResult(
2751                         $dbr->select( 'page',
2752                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
2753                                 $conds,
2754                                 __METHOD__,
2755                                 $options
2756                         )
2757                 );
2758         }
2759
2760         /**
2761          * Is there a version of this page in the deletion archive?
2762          *
2763          * @return Int the number of archived revisions
2764          */
2765         public function isDeleted() {
2766                 if ( $this->getNamespace() < 0 ) {
2767                         $n = 0;
2768                 } else {
2769                         $dbr = wfGetDB( DB_SLAVE );
2770
2771                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2772                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2773                                 __METHOD__
2774                         );
2775                         if ( $this->getNamespace() == NS_FILE ) {
2776                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2777                                         array( 'fa_name' => $this->getDBkey() ),
2778                                         __METHOD__
2779                                 );
2780                         }
2781                 }
2782                 return (int)$n;
2783         }
2784
2785         /**
2786          * Is there a version of this page in the deletion archive?
2787          *
2788          * @return Boolean
2789          */
2790         public function isDeletedQuick() {
2791                 if ( $this->getNamespace() < 0 ) {
2792                         return false;
2793                 }
2794                 $dbr = wfGetDB( DB_SLAVE );
2795                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2796                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2797                         __METHOD__
2798                 );
2799                 if ( !$deleted && $this->getNamespace() == NS_FILE ) {
2800                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2801                                 array( 'fa_name' => $this->getDBkey() ),
2802                                 __METHOD__
2803                         );
2804                 }
2805                 return $deleted;
2806         }
2807
2808         /**
2809          * Get the article ID for this Title from the link cache,
2810          * adding it if necessary
2811          *
2812          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select
2813          *  for update
2814          * @return Int the ID
2815          */
2816         public function getArticleID( $flags = 0 ) {
2817                 if ( $this->getNamespace() < 0 ) {
2818                         return $this->mArticleID = 0;
2819                 }
2820                 $linkCache = LinkCache::singleton();
2821                 if ( $flags & self::GAID_FOR_UPDATE ) {
2822                         $oldUpdate = $linkCache->forUpdate( true );
2823                         $linkCache->clearLink( $this );
2824                         $this->mArticleID = $linkCache->addLinkObj( $this );
2825                         $linkCache->forUpdate( $oldUpdate );
2826                 } else {
2827                         if ( -1 == $this->mArticleID ) {
2828                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2829                         }
2830                 }
2831                 return $this->mArticleID;
2832         }
2833
2834         /**
2835          * Is this an article that is a redirect page?
2836          * Uses link cache, adding it if necessary
2837          *
2838          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2839          * @return Bool
2840          */
2841         public function isRedirect( $flags = 0 ) {
2842                 if ( !is_null( $this->mRedirect ) ) {
2843                         return $this->mRedirect;
2844                 }
2845                 # Calling getArticleID() loads the field from cache as needed
2846                 if ( !$this->getArticleID( $flags ) ) {
2847                         return $this->mRedirect = false;
2848                 }
2849                 $linkCache = LinkCache::singleton();
2850                 $this->mRedirect = (bool)$linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2851
2852                 return $this->mRedirect;
2853         }
2854
2855         /**
2856          * What is the length of this page?
2857          * Uses link cache, adding it if necessary
2858          *
2859          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2860          * @return Int
2861          */
2862         public function getLength( $flags = 0 ) {
2863                 if ( $this->mLength != -1 ) {
2864                         return $this->mLength;
2865                 }
2866                 # Calling getArticleID() loads the field from cache as needed
2867                 if ( !$this->getArticleID( $flags ) ) {
2868                         return $this->mLength = 0;
2869                 }
2870                 $linkCache = LinkCache::singleton();
2871                 $this->mLength = intval( $linkCache->getGoodLinkFieldObj( $this, 'length' ) );
2872
2873                 return $this->mLength;
2874         }
2875
2876         /**
2877          * What is the page_latest field for this page?
2878          *
2879          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2880          * @return Int or 0 if the page doesn't exist
2881          */
2882         public function getLatestRevID( $flags = 0 ) {
2883                 if ( $this->mLatestID !== false ) {
2884                         return intval( $this->mLatestID );
2885                 }
2886                 # Calling getArticleID() loads the field from cache as needed
2887                 if ( !$this->getArticleID( $flags ) ) {
2888                         return $this->mLatestID = 0;
2889                 }
2890                 $linkCache = LinkCache::singleton();
2891                 $this->mLatestID = intval( $linkCache->getGoodLinkFieldObj( $this, 'revision' ) );
2892
2893                 return $this->mLatestID;
2894         }
2895
2896         /**
2897          * This clears some fields in this object, and clears any associated
2898          * keys in the "bad links" section of the link cache.
2899          *
2900          * - This is called from WikiPage::doEdit() and WikiPage::insertOn() to allow
2901          * loading of the new page_id. It's also called from
2902          * WikiPage::doDeleteArticle()
2903          *
2904          * @param $newid Int the new Article ID
2905          */
2906         public function resetArticleID( $newid ) {
2907                 $linkCache = LinkCache::singleton();
2908                 $linkCache->clearLink( $this );
2909
2910                 if ( $newid === false ) {
2911                         $this->mArticleID = -1;
2912                 } else {
2913                         $this->mArticleID = intval( $newid );
2914                 }
2915                 $this->mRestrictionsLoaded = false;
2916                 $this->mRestrictions = array();
2917                 $this->mRedirect = null;
2918                 $this->mLength = -1;
2919                 $this->mLatestID = false;
2920                 $this->mEstimateRevisions = null;
2921         }
2922
2923         /**
2924          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
2925          *
2926          * @param $text String containing title to capitalize
2927          * @param $ns int namespace index, defaults to NS_MAIN
2928          * @return String containing capitalized title
2929          */
2930         public static function capitalize( $text, $ns = NS_MAIN ) {
2931                 global $wgContLang;
2932
2933                 if ( MWNamespace::isCapitalized( $ns ) ) {
2934                         return $wgContLang->ucfirst( $text );
2935                 } else {
2936                         return $text;
2937                 }
2938         }
2939
2940         /**
2941          * Secure and split - main initialisation function for this object
2942          *
2943          * Assumes that mDbkeyform has been set, and is urldecoded
2944          * and uses underscores, but not otherwise munged.  This function
2945          * removes illegal characters, splits off the interwiki and
2946          * namespace prefixes, sets the other forms, and canonicalizes
2947          * everything.
2948          *
2949          * @return Bool true on success
2950          */
2951         private function secureAndSplit() {
2952                 global $wgContLang, $wgLocalInterwiki;
2953
2954                 # Initialisation
2955                 $this->mInterwiki = $this->mFragment = '';
2956                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2957
2958                 $dbkey = $this->mDbkeyform;
2959
2960                 # Strip Unicode bidi override characters.
2961                 # Sometimes they slip into cut-n-pasted page titles, where the
2962                 # override chars get included in list displays.
2963                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
2964
2965                 # Clean up whitespace
2966                 # Note: use of the /u option on preg_replace here will cause
2967                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
2968                 # conveniently disabling them.
2969                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
2970                 $dbkey = trim( $dbkey, '_' );
2971
2972                 if ( $dbkey == '' ) {
2973                         return false;
2974                 }
2975
2976                 if ( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2977                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2978                         return false;
2979                 }
2980
2981                 $this->mDbkeyform = $dbkey;
2982
2983                 # Initial colon indicates main namespace rather than specified default
2984                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
2985                 if ( ':' == $dbkey[0] ) {
2986                         $this->mNamespace = NS_MAIN;
2987                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
2988                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
2989                 }
2990
2991                 # Namespace or interwiki prefix
2992                 $firstPass = true;
2993                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
2994                 do {
2995                         $m = array();
2996                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
2997                                 $p = $m[1];
2998                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
2999                                         # Ordinary namespace
3000                                         $dbkey = $m[2];
3001                                         $this->mNamespace = $ns;
3002                                         # For Talk:X pages, check if X has a "namespace" prefix
3003                                         if ( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
3004                                                 if ( $wgContLang->getNsIndex( $x[1] ) ) {
3005                                                         # Disallow Talk:File:x type titles...
3006                                                         return false;
3007                                                 } elseif ( Interwiki::isValidInterwiki( $x[1] ) ) {
3008                                                         # Disallow Talk:Interwiki:x type titles...
3009                                                         return false;
3010                                                 }
3011                                         }
3012                                 } elseif ( Interwiki::isValidInterwiki( $p ) ) {
3013                                         if ( !$firstPass ) {
3014                                                 # Can't make a local interwiki link to an interwiki link.
3015                                                 # That's just crazy!
3016                                                 return false;
3017                                         }
3018
3019                                         # Interwiki link
3020                                         $dbkey = $m[2];
3021                                         $this->mInterwiki = $wgContLang->lc( $p );
3022
3023                                         # Redundant interwiki prefix to the local wiki
3024                                         if ( $wgLocalInterwiki !== false
3025                                                 && 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) )
3026                                         {
3027                                                 if ( $dbkey == '' ) {
3028                                                         # Can't have an empty self-link
3029                                                         return false;
3030                                                 }
3031                                                 $this->mInterwiki = '';
3032                                                 $firstPass = false;
3033                                                 # Do another namespace split...
3034                                                 continue;
3035                                         }
3036
3037                                         # If there's an initial colon after the interwiki, that also
3038                                         # resets the default namespace
3039                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
3040                                                 $this->mNamespace = NS_MAIN;
3041                                                 $dbkey = substr( $dbkey, 1 );
3042                                         }
3043                                 }
3044                                 # If there's no recognized interwiki or namespace,
3045                                 # then let the colon expression be part of the title.
3046                         }
3047                         break;
3048                 } while ( true );
3049
3050                 # We already know that some pages won't be in the database!
3051                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
3052                         $this->mArticleID = 0;
3053                 }
3054                 $fragment = strstr( $dbkey, '#' );
3055                 if ( false !== $fragment ) {
3056                         $this->setFragment( $fragment );
3057                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
3058                         # remove whitespace again: prevents "Foo_bar_#"
3059                         # becoming "Foo_bar_"
3060                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
3061                 }
3062
3063                 # Reject illegal characters.
3064                 $rxTc = self::getTitleInvalidRegex();
3065                 if ( preg_match( $rxTc, $dbkey ) ) {
3066                         return false;
3067                 }
3068
3069                 # Pages with "/./" or "/../" appearing in the URLs will often be un-
3070                 # reachable due to the way web browsers deal with 'relative' URLs.
3071                 # Also, they conflict with subpage syntax.  Forbid them explicitly.
3072                 if ( strpos( $dbkey, '.' ) !== false &&
3073                          ( $dbkey === '.' || $dbkey === '..' ||
3074                            strpos( $dbkey, './' ) === 0  ||
3075                            strpos( $dbkey, '../' ) === 0 ||
3076                            strpos( $dbkey, '/./' ) !== false ||
3077                            strpos( $dbkey, '/../' ) !== false  ||
3078                            substr( $dbkey, -2 ) == '/.' ||
3079                            substr( $dbkey, -3 ) == '/..' ) )
3080                 {
3081                         return false;
3082                 }
3083
3084                 # Magic tilde sequences? Nu-uh!
3085                 if ( strpos( $dbkey, '~~~' ) !== false ) {
3086                         return false;
3087                 }
3088
3089                 # Limit the size of titles to 255 bytes. This is typically the size of the
3090                 # underlying database field. We make an exception for special pages, which
3091                 # don't need to be stored in the database, and may edge over 255 bytes due
3092                 # to subpage syntax for long titles, e.g. [[Special:Block/Long name]]
3093                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
3094                   strlen( $dbkey ) > 512 )
3095                 {
3096                         return false;
3097                 }
3098
3099                 # Normally, all wiki links are forced to have an initial capital letter so [[foo]]
3100                 # and [[Foo]] point to the same place.  Don't force it for interwikis, since the
3101                 # other site might be case-sensitive.
3102                 $this->mUserCaseDBKey = $dbkey;
3103                 if ( $this->mInterwiki == '' ) {
3104                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
3105                 }
3106
3107                 # Can't make a link to a namespace alone... "empty" local links can only be
3108                 # self-links with a fragment identifier.
3109                 if ( $dbkey == '' && $this->mInterwiki == '' && $this->mNamespace != NS_MAIN ) {
3110                         return false;
3111                 }
3112
3113                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
3114                 // IP names are not allowed for accounts, and can only be referring to
3115                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
3116                 // there are numerous ways to present the same IP. Having sp:contribs scan
3117                 // them all is silly and having some show the edits and others not is
3118                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
3119                 $dbkey = ( $this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK )
3120                         ? IP::sanitizeIP( $dbkey )
3121                         : $dbkey;
3122
3123                 // Any remaining initial :s are illegal.
3124                 if ( $dbkey !== '' && ':' == $dbkey[0] ) {
3125                         return false;
3126                 }
3127
3128                 # Fill fields
3129                 $this->mDbkeyform = $dbkey;
3130                 $this->mUrlform = wfUrlencode( $dbkey );
3131
3132                 $this->mTextform = str_replace( '_', ' ', $dbkey );
3133
3134                 return true;
3135         }
3136
3137         /**
3138          * Get an array of Title objects linking to this Title
3139          * Also stores the IDs in the link cache.
3140          *
3141          * WARNING: do not use this function on arbitrary user-supplied titles!
3142          * On heavily-used templates it will max out the memory.
3143          *
3144          * @param $options Array: may be FOR UPDATE
3145          * @param $table String: table name
3146          * @param $prefix String: fields prefix
3147          * @return Array of Title objects linking here
3148          */
3149         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3150                 if ( count( $options ) > 0 ) {
3151                         $db = wfGetDB( DB_MASTER );
3152                 } else {
3153                         $db = wfGetDB( DB_SLAVE );
3154                 }
3155
3156                 $res = $db->select(
3157                         array( 'page', $table ),
3158                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ),
3159                         array(
3160                                 "{$prefix}_from=page_id",
3161                                 "{$prefix}_namespace" => $this->getNamespace(),
3162                                 "{$prefix}_title"     => $this->getDBkey() ),
3163                         __METHOD__,
3164                         $options
3165                 );
3166
3167                 $retVal = array();
3168                 if ( $res->numRows() ) {
3169                         $linkCache = LinkCache::singleton();
3170                         foreach ( $res as $row ) {
3171                                 $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title );
3172                                 if ( $titleObj ) {
3173                                         $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3174                                         $retVal[] = $titleObj;
3175                                 }
3176                         }
3177                 }
3178                 return $retVal;
3179         }
3180
3181         /**
3182          * Get an array of Title objects using this Title as a template
3183          * Also stores the IDs in the link cache.
3184          *
3185          * WARNING: do not use this function on arbitrary user-supplied titles!
3186          * On heavily-used templates it will max out the memory.
3187          *
3188          * @param $options Array: may be FOR UPDATE
3189          * @return Array of Title the Title objects linking here
3190          */
3191         public function getTemplateLinksTo( $options = array() ) {
3192                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
3193         }
3194
3195         /**
3196          * Get an array of Title objects linked from this Title
3197          * Also stores the IDs in the link cache.
3198          *
3199          * WARNING: do not use this function on arbitrary user-supplied titles!
3200          * On heavily-used templates it will max out the memory.
3201          *
3202          * @param $options Array: may be FOR UPDATE
3203          * @param $table String: table name
3204          * @param $prefix String: fields prefix
3205          * @return Array of Title objects linking here
3206          */
3207         public function getLinksFrom( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3208                 $id = $this->getArticleId();
3209
3210                 # If the page doesn't exist; there can't be any link from this page
3211                 if ( !$id ) {
3212                         return array();
3213                 }
3214
3215                 if ( count( $options ) > 0 ) {
3216                         $db = wfGetDB( DB_MASTER );
3217                 } else {
3218                         $db = wfGetDB( DB_SLAVE );
3219                 }
3220
3221                 $namespaceFiled = "{$prefix}_namespace";
3222                 $titleField = "{$prefix}_title";
3223
3224                 $res = $db->select(
3225                         array( $table, 'page' ),
3226                         array( $namespaceFiled, $titleField, 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ),
3227                         array( "{$prefix}_from" => $id ),
3228                         __METHOD__,
3229                         $options,
3230                         array( 'page' => array( 'LEFT JOIN', array( "page_namespace=$namespaceFiled", "page_title=$titleField" ) ) )
3231                 );
3232
3233                 $retVal = array();
3234                 if ( $res->numRows() ) {
3235                         $linkCache = LinkCache::singleton();
3236                         foreach ( $res as $row ) {
3237                                 $titleObj = Title::makeTitle( $row->$namespaceFiled, $row->$titleField );
3238                                 if ( $titleObj ) {
3239                                         if ( $row->page_id ) {
3240                                                 $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3241                                         } else {
3242                                                 $linkCache->addBadLinkObj( $titleObj );
3243                                         }
3244                                         $retVal[] = $titleObj;
3245                                 }
3246                         }
3247                 }
3248                 return $retVal;
3249         }
3250
3251         /**
3252          * Get an array of Title objects used on this Title as a template
3253          * Also stores the IDs in the link cache.
3254          *
3255          * WARNING: do not use this function on arbitrary user-supplied titles!
3256          * On heavily-used templates it will max out the memory.
3257          *
3258          * @param $options Array: may be FOR UPDATE
3259          * @return Array of Title the Title objects used here
3260          */
3261         public function getTemplateLinksFrom( $options = array() ) {
3262                 return $this->getLinksFrom( $options, 'templatelinks', 'tl' );
3263         }
3264
3265         /**
3266          * Get an array of Title objects referring to non-existent articles linked from this page
3267          *
3268          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
3269          * @return Array of Title the Title objects
3270          */
3271         public function getBrokenLinksFrom() {
3272                 if ( $this->getArticleId() == 0 ) {
3273                         # All links from article ID 0 are false positives
3274                         return array();
3275                 }
3276
3277                 $dbr = wfGetDB( DB_SLAVE );
3278                 $res = $dbr->select(
3279                         array( 'page', 'pagelinks' ),
3280                         array( 'pl_namespace', 'pl_title' ),
3281                         array(
3282                                 'pl_from' => $this->getArticleId(),
3283                                 'page_namespace IS NULL'
3284                         ),
3285                         __METHOD__, array(),
3286                         array(
3287                                 'page' => array(
3288                                         'LEFT JOIN',
3289                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
3290                                 )
3291                         )
3292                 );
3293
3294                 $retVal = array();
3295                 foreach ( $res as $row ) {
3296                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
3297                 }
3298                 return $retVal;
3299         }
3300
3301
3302         /**
3303          * Get a list of URLs to purge from the Squid cache when this
3304          * page changes
3305          *
3306          * @return Array of String the URLs
3307          */
3308         public function getSquidURLs() {
3309                 global $wgContLang;
3310
3311                 $urls = array(
3312                         $this->getInternalURL(),
3313                         $this->getInternalURL( 'action=history' )
3314                 );
3315
3316                 // purge variant urls as well
3317                 if ( $wgContLang->hasVariants() ) {
3318                         $variants = $wgContLang->getVariants();
3319                         foreach ( $variants as $vCode ) {
3320                                 $urls[] = $this->getInternalURL( '', $vCode );
3321                         }
3322                 }
3323
3324                 return $urls;
3325         }
3326
3327         /**
3328          * Purge all applicable Squid URLs
3329          */
3330         public function purgeSquid() {
3331                 global $wgUseSquid;
3332                 if ( $wgUseSquid ) {
3333                         $urls = $this->getSquidURLs();
3334                         $u = new SquidUpdate( $urls );
3335                         $u->doUpdate();
3336                 }
3337         }
3338
3339         /**
3340          * Move this page without authentication
3341          *
3342          * @param $nt Title the new page Title
3343          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3344          */
3345         public function moveNoAuth( &$nt ) {
3346                 return $this->moveTo( $nt, false );
3347         }
3348
3349         /**
3350          * Check whether a given move operation would be valid.
3351          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
3352          *
3353          * @param $nt Title the new title
3354          * @param $auth Bool indicates whether $wgUser's permissions
3355          *  should be checked
3356          * @param $reason String is the log summary of the move, used for spam checking
3357          * @return Mixed True on success, getUserPermissionsErrors()-like array on failure
3358          */
3359         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
3360                 global $wgUser;
3361
3362                 $errors = array();
3363                 if ( !$nt ) {
3364                         // Normally we'd add this to $errors, but we'll get
3365                         // lots of syntax errors if $nt is not an object
3366                         return array( array( 'badtitletext' ) );
3367                 }
3368                 if ( $this->equals( $nt ) ) {
3369                         $errors[] = array( 'selfmove' );
3370                 }
3371                 if ( !$this->isMovable() ) {
3372                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
3373                 }
3374                 if ( $nt->getInterwiki() != '' ) {
3375                         $errors[] = array( 'immobile-target-namespace-iw' );
3376                 }
3377                 if ( !$nt->isMovable() ) {
3378                         $errors[] = array( 'immobile-target-namespace', $nt->getNsText() );
3379                 }
3380
3381                 $oldid = $this->getArticleID();
3382                 $newid = $nt->getArticleID();
3383
3384                 if ( strlen( $nt->getDBkey() ) < 1 ) {
3385                         $errors[] = array( 'articleexists' );
3386                 }
3387                 if ( ( $this->getDBkey() == '' ) ||
3388                          ( !$oldid ) ||
3389                          ( $nt->getDBkey() == '' ) ) {
3390                         $errors[] = array( 'badarticleerror' );
3391                 }
3392
3393                 // Image-specific checks
3394                 if ( $this->getNamespace() == NS_FILE ) {
3395                         $errors = array_merge( $errors, $this->validateFileMoveOperation( $nt ) );
3396                 }
3397
3398                 if ( $nt->getNamespace() == NS_FILE && $this->getNamespace() != NS_FILE ) {
3399                         $errors[] = array( 'nonfile-cannot-move-to-file' );
3400                 }
3401
3402                 if ( $auth ) {
3403                         $errors = wfMergeErrorArrays( $errors,
3404                                 $this->getUserPermissionsErrors( 'move', $wgUser ),
3405                                 $this->getUserPermissionsErrors( 'edit', $wgUser ),
3406                                 $nt->getUserPermissionsErrors( 'move-target', $wgUser ),
3407                                 $nt->getUserPermissionsErrors( 'edit', $wgUser ) );
3408                 }
3409
3410                 $match = EditPage::matchSummarySpamRegex( $reason );
3411                 if ( $match !== false ) {
3412                         // This is kind of lame, won't display nice
3413                         $errors[] = array( 'spamprotectiontext' );
3414                 }
3415
3416                 $err = null;
3417                 if ( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
3418                         $errors[] = array( 'hookaborted', $err );
3419                 }
3420
3421                 # The move is allowed only if (1) the target doesn't exist, or
3422                 # (2) the target is a redirect to the source, and has no history
3423                 # (so we can undo bad moves right after they're done).
3424
3425                 if ( 0 != $newid ) { # Target exists; check for validity
3426                         if ( !$this->isValidMoveTarget( $nt ) ) {
3427                                 $errors[] = array( 'articleexists' );
3428                         }
3429                 } else {
3430                         $tp = $nt->getTitleProtection();
3431                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
3432                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
3433                                 $errors[] = array( 'cantmove-titleprotected' );
3434                         }
3435                 }
3436                 if ( empty( $errors ) ) {
3437                         return true;
3438                 }
3439                 return $errors;
3440         }
3441
3442         /**
3443          * Check if the requested move target is a valid file move target
3444          * @param Title $nt Target title
3445          * @return array List of errors
3446          */
3447         protected function validateFileMoveOperation( $nt ) {
3448                 global $wgUser;
3449
3450                 $errors = array();
3451
3452                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is not allowed until below
3453
3454                 $file = wfLocalFile( $this );
3455                 if ( $file->exists() ) {
3456                         if ( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
3457                                 $errors[] = array( 'imageinvalidfilename' );
3458                         }
3459                         if ( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
3460                                 $errors[] = array( 'imagetypemismatch' );
3461                         }
3462                 }
3463
3464                 if ( $nt->getNamespace() != NS_FILE ) {
3465                         $errors[] = array( 'imagenocrossnamespace' );
3466                         // From here we want to do checks on a file object, so if we can't
3467                         // create one, we must return.
3468                         return $errors;
3469                 }
3470
3471                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is allowed below here
3472
3473                 $destFile = wfLocalFile( $nt );
3474                 if ( !$wgUser->isAllowed( 'reupload-shared' ) && !$destFile->exists() && wfFindFile( $nt ) ) {
3475                         $errors[] = array( 'file-exists-sharedrepo' );
3476                 }
3477
3478                 return $errors;
3479         }
3480
3481         /**
3482          * Move a title to a new location
3483          *
3484          * @param $nt Title the new title
3485          * @param $auth Bool indicates whether $wgUser's permissions
3486          *  should be checked
3487          * @param $reason String the reason for the move
3488          * @param $createRedirect Bool Whether to create a redirect from the old title to the new title.
3489          *  Ignored if the user doesn't have the suppressredirect right.
3490          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3491          */
3492         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
3493                 global $wgUser;
3494                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
3495                 if ( is_array( $err ) ) {
3496                         // Auto-block user's IP if the account was "hard" blocked
3497                         $wgUser->spreadAnyEditBlock();
3498                         return $err;
3499                 }
3500
3501                 // If it is a file, move it first.
3502                 // It is done before all other moving stuff is done because it's hard to revert.
3503                 $dbw = wfGetDB( DB_MASTER );
3504                 if ( $this->getNamespace() == NS_FILE ) {
3505                         $file = wfLocalFile( $this );
3506                         if ( $file->exists() ) {
3507                                 $status = $file->move( $nt );
3508                                 if ( !$status->isOk() ) {
3509                                         return $status->getErrorsArray();
3510                                 }
3511                         }
3512                         // Clear RepoGroup process cache
3513                         RepoGroup::singleton()->clearCache( $this );
3514                         RepoGroup::singleton()->clearCache( $nt ); # clear false negative cache
3515                 }
3516
3517                 $dbw->begin(); # If $file was a LocalFile, its transaction would have closed our own.
3518                 $pageid = $this->getArticleID( self::GAID_FOR_UPDATE );
3519                 $protected = $this->isProtected();
3520
3521                 // Do the actual move
3522                 $err = $this->moveToInternal( $nt, $reason, $createRedirect );
3523                 if ( is_array( $err ) ) {
3524                         # @todo FIXME: What about the File we have already moved?
3525                         $dbw->rollback();
3526                         return $err;
3527                 }
3528
3529                 // Refresh the sortkey for this row.  Be careful to avoid resetting
3530                 // cl_timestamp, which may disturb time-based lists on some sites.
3531                 $prefixes = $dbw->select(
3532                         'categorylinks',
3533                         array( 'cl_sortkey_prefix', 'cl_to' ),
3534                         array( 'cl_from' => $pageid ),
3535                         __METHOD__
3536                 );
3537                 foreach ( $prefixes as $prefixRow ) {
3538                         $prefix = $prefixRow->cl_sortkey_prefix;
3539                         $catTo = $prefixRow->cl_to;
3540                         $dbw->update( 'categorylinks',
3541                                 array(
3542                                         'cl_sortkey' => Collation::singleton()->getSortKey(
3543                                                 $nt->getCategorySortkey( $prefix ) ),
3544                                         'cl_timestamp=cl_timestamp' ),
3545                                 array(
3546                                         'cl_from' => $pageid,
3547                                         'cl_to' => $catTo ),
3548                                 __METHOD__
3549                         );
3550                 }
3551
3552                 $redirid = $this->getArticleID();
3553
3554                 if ( $protected ) {
3555                         # Protect the redirect title as the title used to be...
3556                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
3557                                 array(
3558                                         'pr_page'    => $redirid,
3559                                         'pr_type'    => 'pr_type',
3560                                         'pr_level'   => 'pr_level',
3561                                         'pr_cascade' => 'pr_cascade',
3562                                         'pr_user'    => 'pr_user',
3563                                         'pr_expiry'  => 'pr_expiry'
3564                                 ),
3565                                 array( 'pr_page' => $pageid ),
3566                                 __METHOD__,
3567                                 array( 'IGNORE' )
3568                         );
3569                         # Update the protection log
3570                         $log = new LogPage( 'protect' );
3571                         $comment = wfMsgForContent( 'prot_1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
3572                         if ( $reason ) {
3573                                 $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3574                         }
3575                         // @todo FIXME: $params?
3576                         $log->addEntry( 'move_prot', $nt, $comment, array( $this->getPrefixedText() ) );
3577                 }
3578
3579                 # Update watchlists
3580                 $oldnamespace = $this->getNamespace() & ~1;
3581                 $newnamespace = $nt->getNamespace() & ~1;
3582                 $oldtitle = $this->getDBkey();
3583                 $newtitle = $nt->getDBkey();
3584
3585                 if ( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
3586                         WatchedItem::duplicateEntries( $this, $nt );
3587                 }
3588
3589                 $dbw->commit();
3590
3591                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3592                 return true;
3593         }
3594
3595         /**
3596          * Move page to a title which is either a redirect to the
3597          * source page or nonexistent
3598          *
3599          * @param $nt Title the page to move to, which should be a redirect or nonexistent
3600          * @param $reason String The reason for the move
3601          * @param $createRedirect Bool Whether to leave a redirect at the old title.  Ignored
3602          *   if the user doesn't have the suppressredirect right
3603          */
3604         private function moveToInternal( &$nt, $reason = '', $createRedirect = true ) {
3605                 global $wgUser, $wgContLang;
3606
3607                 if ( $nt->exists() ) {
3608                         $moveOverRedirect = true;
3609                         $logType = 'move_redir';
3610                 } else {
3611                         $moveOverRedirect = false;
3612                         $logType = 'move';
3613                 }
3614
3615                 $redirectSuppressed = !$createRedirect && $wgUser->isAllowed( 'suppressredirect' );
3616
3617                 $logEntry = new ManualLogEntry( 'move', $logType );
3618                 $logEntry->setPerformer( $wgUser );
3619                 $logEntry->setTarget( $this );
3620                 $logEntry->setComment( $reason );
3621                 $logEntry->setParameters( array(
3622                         '4::target' => $nt->getPrefixedText(),
3623                         '5::noredir' => $redirectSuppressed ? '1': '0',
3624                 ) );
3625
3626                 $formatter = LogFormatter::newFromEntry( $logEntry );
3627                 $formatter->setContext( RequestContext::newExtraneousContext( $this ) );
3628                 $comment = $formatter->getPlainActionText();
3629                 if ( $reason ) {
3630                         $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3631                 }
3632                 # Truncate for whole multibyte characters.
3633                 $comment = $wgContLang->truncate( $comment, 255 );
3634
3635                 $oldid = $this->getArticleID();
3636                 $latest = $this->getLatestRevID();
3637
3638                 $dbw = wfGetDB( DB_MASTER );
3639
3640                 $newpage = WikiPage::factory( $nt );
3641
3642                 if ( $moveOverRedirect ) {
3643                         $newid = $nt->getArticleID();
3644
3645                         # Delete the old redirect. We don't save it to history since
3646                         # by definition if we've got here it's rather uninteresting.
3647                         # We have to remove it so that the next step doesn't trigger
3648                         # a conflict on the unique namespace+title index...
3649                         $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3650
3651                         $newpage->doDeleteUpdates( $newid );
3652                 }
3653
3654                 # Save a null revision in the page's history notifying of the move
3655                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3656                 if ( !is_object( $nullRevision ) ) {
3657                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3658                 }
3659                 $nullRevId = $nullRevision->insertOn( $dbw );
3660
3661                 # Change the name of the target page:
3662                 $dbw->update( 'page',
3663                         /* SET */ array(
3664                                 'page_namespace' => $nt->getNamespace(),
3665                                 'page_title'     => $nt->getDBkey(),
3666                         ),
3667                         /* WHERE */ array( 'page_id' => $oldid ),
3668                         __METHOD__
3669                 );
3670
3671                 $this->resetArticleID( 0 );
3672                 $nt->resetArticleID( $oldid );
3673
3674                 $newpage->updateRevisionOn( $dbw, $nullRevision );
3675
3676                 wfRunHooks( 'NewRevisionFromEditComplete',
3677                         array( $newpage, $nullRevision, $latest, $wgUser ) );
3678
3679                 $newpage->doEditUpdates( $nullRevision, $wgUser, array( 'changed' => false ) );
3680
3681                 # Recreate the redirect, this time in the other direction.
3682                 if ( $redirectSuppressed ) {
3683                         WikiPage::onArticleDelete( $this );
3684                 } else {
3685                         $mwRedir = MagicWord::get( 'redirect' );
3686                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3687                         $redirectArticle = WikiPage::factory( $this );
3688                         $newid = $redirectArticle->insertOn( $dbw );
3689                         if ( $newid ) { // sanity
3690                                 $redirectRevision = new Revision( array(
3691                                         'page'    => $newid,
3692                                         'comment' => $comment,
3693                                         'text'    => $redirectText ) );
3694                                 $redirectRevision->insertOn( $dbw );
3695                                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3696
3697                                 wfRunHooks( 'NewRevisionFromEditComplete',
3698                                         array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3699
3700                                 $redirectArticle->doEditUpdates( $redirectRevision, $wgUser, array( 'created' => true ) );
3701                         }
3702                 }
3703
3704                 # Log the move
3705                 $logid = $logEntry->insert();
3706                 $logEntry->publish( $logid );
3707         }
3708
3709         /**
3710          * Move this page's subpages to be subpages of $nt
3711          *
3712          * @param $nt Title Move target
3713          * @param $auth bool Whether $wgUser's permissions should be checked
3714          * @param $reason string The reason for the move
3715          * @param $createRedirect bool Whether to create redirects from the old subpages to
3716          *     the new ones Ignored if the user doesn't have the 'suppressredirect' right
3717          * @return mixed array with old page titles as keys, and strings (new page titles) or
3718          *     arrays (errors) as values, or an error array with numeric indices if no pages
3719          *     were moved
3720          */
3721         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3722                 global $wgMaximumMovedPages;
3723                 // Check permissions
3724                 if ( !$this->userCan( 'move-subpages' ) ) {
3725                         return array( 'cant-move-subpages' );
3726                 }
3727                 // Do the source and target namespaces support subpages?
3728                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
3729                         return array( 'namespace-nosubpages',
3730                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3731                 }
3732                 if ( !MWNamespace::hasSubpages( $nt->getNamespace() ) ) {
3733                         return array( 'namespace-nosubpages',
3734                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3735                 }
3736
3737                 $subpages = $this->getSubpages( $wgMaximumMovedPages + 1 );
3738                 $retval = array();
3739                 $count = 0;
3740                 foreach ( $subpages as $oldSubpage ) {
3741                         $count++;
3742                         if ( $count > $wgMaximumMovedPages ) {
3743                                 $retval[$oldSubpage->getPrefixedTitle()] =
3744                                                 array( 'movepage-max-pages',
3745                                                         $wgMaximumMovedPages );
3746                                 break;
3747                         }
3748
3749                         // We don't know whether this function was called before
3750                         // or after moving the root page, so check both
3751                         // $this and $nt
3752                         if ( $oldSubpage->getArticleId() == $this->getArticleId() ||
3753                                         $oldSubpage->getArticleID() == $nt->getArticleId() )
3754                         {
3755                                 // When moving a page to a subpage of itself,
3756                                 // don't move it twice
3757                                 continue;
3758                         }
3759                         $newPageName = preg_replace(
3760                                         '#^' . preg_quote( $this->getDBkey(), '#' ) . '#',
3761                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3762                                         $oldSubpage->getDBkey() );
3763                         if ( $oldSubpage->isTalkPage() ) {
3764                                 $newNs = $nt->getTalkPage()->getNamespace();
3765                         } else {
3766                                 $newNs = $nt->getSubjectPage()->getNamespace();
3767                         }
3768                         # Bug 14385: we need makeTitleSafe because the new page names may
3769                         # be longer than 255 characters.
3770                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3771
3772                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3773                         if ( $success === true ) {
3774                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3775                         } else {
3776                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3777                         }
3778                 }
3779                 return $retval;
3780         }
3781
3782         /**
3783          * Checks if this page is just a one-rev redirect.
3784          * Adds lock, so don't use just for light purposes.
3785          *
3786          * @return Bool
3787          */
3788         public function isSingleRevRedirect() {
3789                 $dbw = wfGetDB( DB_MASTER );
3790                 # Is it a redirect?
3791                 $row = $dbw->selectRow( 'page',
3792                         array( 'page_is_redirect', 'page_latest', 'page_id' ),
3793                         $this->pageCond(),
3794                         __METHOD__,
3795                         array( 'FOR UPDATE' )
3796                 );
3797                 # Cache some fields we may want
3798                 $this->mArticleID = $row ? intval( $row->page_id ) : 0;
3799                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3800                 $this->mLatestID = $row ? intval( $row->page_latest ) : false;
3801                 if ( !$this->mRedirect ) {
3802                         return false;
3803                 }
3804                 # Does the article have a history?
3805                 $row = $dbw->selectField( array( 'page', 'revision' ),
3806                         'rev_id',
3807                         array( 'page_namespace' => $this->getNamespace(),
3808                                 'page_title' => $this->getDBkey(),
3809                                 'page_id=rev_page',
3810                                 'page_latest != rev_id'
3811                         ),
3812                         __METHOD__,
3813                         array( 'FOR UPDATE' )
3814                 );
3815                 # Return true if there was no history
3816                 return ( $row === false );
3817         }
3818
3819         /**
3820          * Checks if $this can be moved to a given Title
3821          * - Selects for update, so don't call it unless you mean business
3822          *
3823          * @param $nt Title the new title to check
3824          * @return Bool
3825          */
3826         public function isValidMoveTarget( $nt ) {
3827                 # Is it an existing file?
3828                 if ( $nt->getNamespace() == NS_FILE ) {
3829                         $file = wfLocalFile( $nt );
3830                         if ( $file->exists() ) {
3831                                 wfDebug( __METHOD__ . ": file exists\n" );
3832                                 return false;
3833                         }
3834                 }
3835                 # Is it a redirect with no history?
3836                 if ( !$nt->isSingleRevRedirect() ) {
3837                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3838                         return false;
3839                 }
3840                 # Get the article text
3841                 $rev = Revision::newFromTitle( $nt );
3842                 if( !is_object( $rev ) ){
3843                         return false;
3844                 }
3845                 $text = $rev->getText();
3846                 # Does the redirect point to the source?
3847                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3848                 $m = array();
3849                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
3850                         $redirTitle = Title::newFromText( $m[1] );
3851                         if ( !is_object( $redirTitle ) ||
3852                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3853                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
3854                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3855                                 return false;
3856                         }
3857                 } else {
3858                         # Fail safe
3859                         wfDebug( __METHOD__ . ": failsafe\n" );
3860                         return false;
3861                 }
3862                 return true;
3863         }
3864
3865         /**
3866          * Get categories to which this Title belongs and return an array of
3867          * categories' names.
3868          *
3869          * @return Array of parents in the form:
3870          *        $parent => $currentarticle
3871          */
3872         public function getParentCategories() {
3873                 global $wgContLang;
3874
3875                 $data = array();
3876
3877                 $titleKey = $this->getArticleId();
3878
3879                 if ( $titleKey === 0 ) {
3880                         return $data;
3881                 }
3882
3883                 $dbr = wfGetDB( DB_SLAVE );
3884
3885                 $res = $dbr->select( 'categorylinks', '*',
3886                         array(
3887                                 'cl_from' => $titleKey,
3888                         ),
3889                         __METHOD__,
3890                         array()
3891                 );
3892
3893                 if ( $dbr->numRows( $res ) > 0 ) {
3894                         foreach ( $res as $row ) {
3895                                 // $data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
3896                                 $data[$wgContLang->getNSText( NS_CATEGORY ) . ':' . $row->cl_to] = $this->getFullText();
3897                         }
3898                 }
3899                 return $data;
3900         }
3901
3902         /**
3903          * Get a tree of parent categories
3904          *
3905          * @param $children Array with the children in the keys, to check for circular refs
3906          * @return Array Tree of parent categories
3907          */
3908         public function getParentCategoryTree( $children = array() ) {
3909                 $stack = array();
3910                 $parents = $this->getParentCategories();
3911
3912                 if ( $parents ) {
3913                         foreach ( $parents as $parent => $current ) {
3914                                 if ( array_key_exists( $parent, $children ) ) {
3915                                         # Circular reference
3916                                         $stack[$parent] = array();
3917                                 } else {
3918                                         $nt = Title::newFromText( $parent );
3919                                         if ( $nt ) {
3920                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array( $parent => 1 ) );
3921                                         }
3922                                 }
3923                         }
3924                 }
3925
3926                 return $stack;
3927         }
3928
3929         /**
3930          * Get an associative array for selecting this title from
3931          * the "page" table
3932          *
3933          * @return Array suitable for the $where parameter of DB::select()
3934          */
3935         public function pageCond() {
3936                 if ( $this->mArticleID > 0 ) {
3937                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
3938                         return array( 'page_id' => $this->mArticleID );
3939                 } else {
3940                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
3941                 }
3942         }
3943
3944         /**
3945          * Get the revision ID of the previous revision
3946          *
3947          * @param $revId Int Revision ID. Get the revision that was before this one.
3948          * @param $flags Int Title::GAID_FOR_UPDATE
3949          * @return Int|Bool Old revision ID, or FALSE if none exists
3950          */
3951         public function getPreviousRevisionID( $revId, $flags = 0 ) {
3952                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3953                 return $db->selectField( 'revision', 'rev_id',
3954                         array(
3955                                 'rev_page' => $this->getArticleId( $flags ),
3956                                 'rev_id < ' . intval( $revId )
3957                         ),
3958                         __METHOD__,
3959                         array( 'ORDER BY' => 'rev_id DESC' )
3960                 );
3961         }
3962
3963         /**
3964          * Get the revision ID of the next revision
3965          *
3966          * @param $revId Int Revision ID. Get the revision that was after this one.
3967          * @param $flags Int Title::GAID_FOR_UPDATE
3968          * @return Int|Bool Next revision ID, or FALSE if none exists
3969          */
3970         public function getNextRevisionID( $revId, $flags = 0 ) {
3971                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3972                 return $db->selectField( 'revision', 'rev_id',
3973                         array(
3974                                 'rev_page' => $this->getArticleId( $flags ),
3975                                 'rev_id > ' . intval( $revId )
3976                         ),
3977                         __METHOD__,
3978                         array( 'ORDER BY' => 'rev_id' )
3979                 );
3980         }
3981
3982         /**
3983          * Get the first revision of the page
3984          *
3985          * @param $flags Int Title::GAID_FOR_UPDATE
3986          * @return Revision|Null if page doesn't exist
3987          */
3988         public function getFirstRevision( $flags = 0 ) {
3989                 $pageId = $this->getArticleId( $flags );
3990                 if ( $pageId ) {
3991                         $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3992                         $row = $db->selectRow( 'revision', '*',
3993                                 array( 'rev_page' => $pageId ),
3994                                 __METHOD__,
3995                                 array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
3996                         );
3997                         if ( $row ) {
3998                                 return new Revision( $row );
3999                         }
4000                 }
4001                 return null;
4002         }
4003
4004         /**
4005          * Get the oldest revision timestamp of this page
4006          *
4007          * @param $flags Int Title::GAID_FOR_UPDATE
4008          * @return String: MW timestamp
4009          */
4010         public function getEarliestRevTime( $flags = 0 ) {
4011                 $rev = $this->getFirstRevision( $flags );
4012                 return $rev ? $rev->getTimestamp() : null;
4013         }
4014
4015         /**
4016          * Check if this is a new page
4017          *
4018          * @return bool
4019          */
4020         public function isNewPage() {
4021                 $dbr = wfGetDB( DB_SLAVE );
4022                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
4023         }
4024
4025         /**
4026          * Check whether the number of revisions of this page surpasses $wgDeleteRevisionsLimit
4027          *
4028          * @return bool
4029          */
4030         public function isBigDeletion() {
4031                 global $wgDeleteRevisionsLimit;
4032
4033                 if ( !$wgDeleteRevisionsLimit ) {
4034                         return false;
4035                 }
4036
4037                 $revCount = $this->estimateRevisionCount();
4038                 return $revCount > $wgDeleteRevisionsLimit;
4039         }
4040
4041         /**
4042          * Get the  approximate revision count of this page.
4043          *
4044          * @return int
4045          */
4046         public function estimateRevisionCount() {
4047                 if ( !$this->exists() ) {
4048                         return 0;
4049                 }
4050
4051                 if ( $this->mEstimateRevisions === null ) {
4052                         $dbr = wfGetDB( DB_SLAVE );
4053                         $this->mEstimateRevisions = $dbr->estimateRowCount( 'revision', '*',
4054                                 array( 'rev_page' => $this->getArticleId() ), __METHOD__ );
4055                 }
4056
4057                 return $this->mEstimateRevisions;
4058         }
4059
4060         /**
4061          * Get the number of revisions between the given revision.
4062          * Used for diffs and other things that really need it.
4063          *
4064          * @param $old int|Revision Old revision or rev ID (first before range)
4065          * @param $new int|Revision New revision or rev ID (first after range)
4066          * @return Int Number of revisions between these revisions.
4067          */
4068         public function countRevisionsBetween( $old, $new ) {
4069                 if ( !( $old instanceof Revision ) ) {
4070                         $old = Revision::newFromTitle( $this, (int)$old );
4071                 }
4072                 if ( !( $new instanceof Revision ) ) {
4073                         $new = Revision::newFromTitle( $this, (int)$new );
4074                 }
4075                 if ( !$old || !$new ) {
4076                         return 0; // nothing to compare
4077                 }
4078                 $dbr = wfGetDB( DB_SLAVE );
4079                 return (int)$dbr->selectField( 'revision', 'count(*)',
4080                         array(
4081                                 'rev_page' => $this->getArticleId(),
4082                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4083                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4084                         ),
4085                         __METHOD__
4086                 );
4087         }
4088
4089         /**
4090          * Get the number of authors between the given revision IDs.
4091          * Used for diffs and other things that really need it.
4092          *
4093          * @param $old int|Revision Old revision or rev ID (first before range)
4094          * @param $new int|Revision New revision or rev ID (first after range)
4095          * @param $limit Int Maximum number of authors
4096          * @return Int Number of revision authors between these revisions.
4097          */
4098         public function countAuthorsBetween( $old, $new, $limit ) {
4099                 if ( !( $old instanceof Revision ) ) {
4100                         $old = Revision::newFromTitle( $this, (int)$old );
4101                 }
4102                 if ( !( $new instanceof Revision ) ) {
4103                         $new = Revision::newFromTitle( $this, (int)$new );
4104                 }
4105                 if ( !$old || !$new ) {
4106                         return 0; // nothing to compare
4107                 }
4108                 $dbr = wfGetDB( DB_SLAVE );
4109                 $res = $dbr->select( 'revision', 'DISTINCT rev_user_text',
4110                         array(
4111                                 'rev_page' => $this->getArticleID(),
4112                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4113                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4114                         ), __METHOD__,
4115                         array( 'LIMIT' => $limit + 1 ) // add one so caller knows it was truncated
4116                 );
4117                 return (int)$dbr->numRows( $res );
4118         }
4119
4120         /**
4121          * Compare with another title.
4122          *
4123          * @param $title Title
4124          * @return Bool
4125          */
4126         public function equals( Title $title ) {
4127                 // Note: === is necessary for proper matching of number-like titles.
4128                 return $this->getInterwiki() === $title->getInterwiki()
4129                         && $this->getNamespace() == $title->getNamespace()
4130                         && $this->getDBkey() === $title->getDBkey();
4131         }
4132
4133         /**
4134          * Check if this title is a subpage of another title
4135          *
4136          * @param $title Title
4137          * @return Bool
4138          */
4139         public function isSubpageOf( Title $title ) {
4140                 return $this->getInterwiki() === $title->getInterwiki()
4141                         && $this->getNamespace() == $title->getNamespace()
4142                         && strpos( $this->getDBkey(), $title->getDBkey() . '/' ) === 0;
4143         }
4144
4145         /**
4146          * Check if page exists.  For historical reasons, this function simply
4147          * checks for the existence of the title in the page table, and will
4148          * thus return false for interwiki links, special pages and the like.
4149          * If you want to know if a title can be meaningfully viewed, you should
4150          * probably call the isKnown() method instead.
4151          *
4152          * @return Bool
4153          */
4154         public function exists() {
4155                 return $this->getArticleId() != 0;
4156         }
4157
4158         /**
4159          * Should links to this title be shown as potentially viewable (i.e. as
4160          * "bluelinks"), even if there's no record by this title in the page
4161          * table?
4162          *
4163          * This function is semi-deprecated for public use, as well as somewhat
4164          * misleadingly named.  You probably just want to call isKnown(), which
4165          * calls this function internally.
4166          *
4167          * (ISSUE: Most of these checks are cheap, but the file existence check
4168          * can potentially be quite expensive.  Including it here fixes a lot of
4169          * existing code, but we might want to add an optional parameter to skip
4170          * it and any other expensive checks.)
4171          *
4172          * @return Bool
4173          */
4174         public function isAlwaysKnown() {
4175                 if ( $this->mInterwiki != '' ) {
4176                         return true;  // any interwiki link might be viewable, for all we know
4177                 }
4178                 switch( $this->mNamespace ) {
4179                         case NS_MEDIA:
4180                         case NS_FILE:
4181                                 // file exists, possibly in a foreign repo
4182                                 return (bool)wfFindFile( $this );
4183                         case NS_SPECIAL:
4184                                 // valid special page
4185                                 return SpecialPageFactory::exists( $this->getDBkey() );
4186                         case NS_MAIN:
4187                                 // selflink, possibly with fragment
4188                                 return $this->mDbkeyform == '';
4189                         case NS_MEDIAWIKI:
4190                                 // known system message
4191                                 return $this->hasSourceText() !== false;
4192                         default:
4193                                 return false;
4194                 }
4195         }
4196
4197         /**
4198          * Does this title refer to a page that can (or might) be meaningfully
4199          * viewed?  In particular, this function may be used to determine if
4200          * links to the title should be rendered as "bluelinks" (as opposed to
4201          * "redlinks" to non-existent pages).
4202          *
4203          * @return Bool
4204          */
4205         public function isKnown() {
4206                 return $this->isAlwaysKnown() || $this->exists();
4207         }
4208
4209         /**
4210          * Does this page have source text?
4211          *
4212          * @return Boolean
4213          */
4214         public function hasSourceText() {
4215                 if ( $this->exists() ) {
4216                         return true;
4217                 }
4218
4219                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
4220                         // If the page doesn't exist but is a known system message, default
4221                         // message content will be displayed, same for language subpages-
4222                         // Use always content language to avoid loading hundreds of languages
4223                         // to get the link color.
4224                         global $wgContLang;
4225                         list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4226                         $message = wfMessage( $name )->inLanguage( $wgContLang )->useDatabase( false );
4227                         return $message->exists();
4228                 }
4229
4230                 return false;
4231         }
4232
4233         /**
4234          * Get the default message text or false if the message doesn't exist
4235          *
4236          * @return String or false
4237          */
4238         public function getDefaultMessageText() {
4239                 global $wgContLang;
4240
4241                 if ( $this->getNamespace() != NS_MEDIAWIKI ) { // Just in case
4242                         return false;
4243                 }
4244
4245                 list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4246                 $message = wfMessage( $name )->inLanguage( $lang )->useDatabase( false );
4247
4248                 if ( $message->exists() ) {
4249                         return $message->plain();
4250                 } else {
4251                         return false;
4252                 }
4253         }
4254
4255         /**
4256          * Updates page_touched for this page; called from LinksUpdate.php
4257          *
4258          * @return Bool true if the update succeded
4259          */
4260         public function invalidateCache() {
4261                 if ( wfReadOnly() ) {
4262                         return false;
4263                 }
4264                 $dbw = wfGetDB( DB_MASTER );
4265                 $success = $dbw->update(
4266                         'page',
4267                         array( 'page_touched' => $dbw->timestamp() ),
4268                         $this->pageCond(),
4269                         __METHOD__
4270                 );
4271                 HTMLFileCache::clearFileCache( $this );
4272                 return $success;
4273         }
4274
4275         /**
4276          * Update page_touched timestamps and send squid purge messages for
4277          * pages linking to this title. May be sent to the job queue depending
4278          * on the number of links. Typically called on create and delete.
4279          */
4280         public function touchLinks() {
4281                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
4282                 $u->doUpdate();
4283
4284                 if ( $this->getNamespace() == NS_CATEGORY ) {
4285                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
4286                         $u->doUpdate();
4287                 }
4288         }
4289
4290         /**
4291          * Get the last touched timestamp
4292          *
4293          * @param $db DatabaseBase: optional db
4294          * @return String last-touched timestamp
4295          */
4296         public function getTouched( $db = null ) {
4297                 $db = isset( $db ) ? $db : wfGetDB( DB_SLAVE );
4298                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
4299                 return $touched;
4300         }
4301
4302         /**
4303          * Get the timestamp when this page was updated since the user last saw it.
4304          *
4305          * @param $user User
4306          * @return String|Null
4307          */
4308         public function getNotificationTimestamp( $user = null ) {
4309                 global $wgUser, $wgShowUpdatedMarker;
4310                 // Assume current user if none given
4311                 if ( !$user ) {
4312                         $user = $wgUser;
4313                 }
4314                 // Check cache first
4315                 $uid = $user->getId();
4316                 // avoid isset here, as it'll return false for null entries
4317                 if ( array_key_exists( $uid, $this->mNotificationTimestamp ) ) {
4318                         return $this->mNotificationTimestamp[$uid];
4319                 }
4320                 if ( !$uid || !$wgShowUpdatedMarker ) {
4321                         return $this->mNotificationTimestamp[$uid] = false;
4322                 }
4323                 // Don't cache too much!
4324                 if ( count( $this->mNotificationTimestamp ) >= self::CACHE_MAX ) {
4325                         $this->mNotificationTimestamp = array();
4326                 }
4327                 $dbr = wfGetDB( DB_SLAVE );
4328                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
4329                         'wl_notificationtimestamp',
4330                         array( 'wl_namespace' => $this->getNamespace(),
4331                                 'wl_title' => $this->getDBkey(),
4332                                 'wl_user' => $user->getId()
4333                         ),
4334                         __METHOD__
4335                 );
4336                 return $this->mNotificationTimestamp[$uid];
4337         }
4338
4339         /**
4340          * Generate strings used for xml 'id' names in monobook tabs
4341          *
4342          * @param $prepend string defaults to 'nstab-'
4343          * @return String XML 'id' name
4344          */
4345         public function getNamespaceKey( $prepend = 'nstab-' ) {
4346                 global $wgContLang;
4347                 // Gets the subject namespace if this title
4348                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
4349                 // Checks if cononical namespace name exists for namespace
4350                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
4351                         // Uses canonical namespace name
4352                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
4353                 } else {
4354                         // Uses text of namespace
4355                         $namespaceKey = $this->getSubjectNsText();
4356                 }
4357                 // Makes namespace key lowercase
4358                 $namespaceKey = $wgContLang->lc( $namespaceKey );
4359                 // Uses main
4360                 if ( $namespaceKey == '' ) {
4361                         $namespaceKey = 'main';
4362                 }
4363                 // Changes file to image for backwards compatibility
4364                 if ( $namespaceKey == 'file' ) {
4365                         $namespaceKey = 'image';
4366                 }
4367                 return $prepend . $namespaceKey;
4368         }
4369
4370         /**
4371          * Get all extant redirects to this Title
4372          *
4373          * @param $ns Int|Null Single namespace to consider; NULL to consider all namespaces
4374          * @return Array of Title redirects to this title
4375          */
4376         public function getRedirectsHere( $ns = null ) {
4377                 $redirs = array();
4378
4379                 $dbr = wfGetDB( DB_SLAVE );
4380                 $where = array(
4381                         'rd_namespace' => $this->getNamespace(),
4382                         'rd_title' => $this->getDBkey(),
4383                         'rd_from = page_id'
4384                 );
4385                 if ( !is_null( $ns ) ) {
4386                         $where['page_namespace'] = $ns;
4387                 }
4388
4389                 $res = $dbr->select(
4390                         array( 'redirect', 'page' ),
4391                         array( 'page_namespace', 'page_title' ),
4392                         $where,
4393                         __METHOD__
4394                 );
4395
4396                 foreach ( $res as $row ) {
4397                         $redirs[] = self::newFromRow( $row );
4398                 }
4399                 return $redirs;
4400         }
4401
4402         /**
4403          * Check if this Title is a valid redirect target
4404          *
4405          * @return Bool
4406          */
4407         public function isValidRedirectTarget() {
4408                 global $wgInvalidRedirectTargets;
4409
4410                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
4411                 if ( $this->isSpecial( 'Userlogout' ) ) {
4412                         return false;
4413                 }
4414
4415                 foreach ( $wgInvalidRedirectTargets as $target ) {
4416                         if ( $this->isSpecial( $target ) ) {
4417                                 return false;
4418                         }
4419                 }
4420
4421                 return true;
4422         }
4423
4424         /**
4425          * Get a backlink cache object
4426          *
4427          * @return BacklinkCache
4428          */
4429         function getBacklinkCache() {
4430                 if ( is_null( $this->mBacklinkCache ) ) {
4431                         $this->mBacklinkCache = new BacklinkCache( $this );
4432                 }
4433                 return $this->mBacklinkCache;
4434         }
4435
4436         /**
4437          * Whether the magic words __INDEX__ and __NOINDEX__ function for  this page.
4438          *
4439          * @return Boolean
4440          */
4441         public function canUseNoindex() {
4442                 global $wgContentNamespaces, $wgExemptFromUserRobotsControl;
4443
4444                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
4445                         ? $wgContentNamespaces
4446                         : $wgExemptFromUserRobotsControl;
4447
4448                 return !in_array( $this->mNamespace, $bannedNamespaces );
4449
4450         }
4451
4452         /**
4453          * Returns the raw sort key to be used for categories, with the specified
4454          * prefix.  This will be fed to Collation::getSortKey() to get a
4455          * binary sortkey that can be used for actual sorting.
4456          *
4457          * @param $prefix string The prefix to be used, specified using
4458          *   {{defaultsort:}} or like [[Category:Foo|prefix]].  Empty for no
4459          *   prefix.
4460          * @return string
4461          */
4462         public function getCategorySortkey( $prefix = '' ) {
4463                 $unprefixed = $this->getText();
4464
4465                 // Anything that uses this hook should only depend
4466                 // on the Title object passed in, and should probably
4467                 // tell the users to run updateCollations.php --force
4468                 // in order to re-sort existing category relations.
4469                 wfRunHooks( 'GetDefaultSortkey', array( $this, &$unprefixed ) );
4470                 if ( $prefix !== '' ) {
4471                         # Separate with a line feed, so the unprefixed part is only used as
4472                         # a tiebreaker when two pages have the exact same prefix.
4473                         # In UCA, tab is the only character that can sort above LF
4474                         # so we strip both of them from the original prefix.
4475                         $prefix = strtr( $prefix, "\n\t", '  ' );
4476                         return "$prefix\n$unprefixed";
4477                 }
4478                 return $unprefixed;
4479         }
4480
4481         /**
4482          * Get the language in which the content of this page is written.
4483          * Defaults to $wgContLang, but in certain cases it can be e.g.
4484          * $wgLang (such as special pages, which are in the user language).
4485          *
4486          * @since 1.18
4487          * @return object Language
4488          */
4489         public function getPageLanguage() {
4490                 global $wgLang;
4491                 if ( $this->isSpecialPage() ) {
4492                         // special pages are in the user language
4493                         return $wgLang;
4494                 } elseif ( $this->isCssOrJsPage() ) {
4495                         // css/js should always be LTR and is, in fact, English
4496                         return wfGetLangObj( 'en' );
4497                 } elseif ( $this->getNamespace() == NS_MEDIAWIKI ) {
4498                         // Parse mediawiki messages with correct target language
4499                         list( /* $unused */, $lang ) = MessageCache::singleton()->figureMessage( $this->getText() );
4500                         return wfGetLangObj( $lang );
4501                 }
4502                 global $wgContLang;
4503                 // If nothing special, it should be in the wiki content language
4504                 $pageLang = $wgContLang;
4505                 // Hook at the end because we don't want to override the above stuff
4506                 wfRunHooks( 'PageContentLanguage', array( $this, &$pageLang, $wgLang ) );
4507                 return wfGetLangObj( $pageLang );
4508         }
4509 }