includes/Title.php

   1 <?php
   2 /**
   3  * Representation a title within %MediaWiki.
   4  *
   5  * See title.txt
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  20  * http://www.gnu.org/copyleft/gpl.html
  21  *
  22  * @file
  23  */
  24
  25 /**
  26  * Represents a title within MediaWiki.
  27  * Optionally may contain an interwiki designation or namespace.
  28  * @note This class can fetch various kinds of data from the database;
  29  *       however, it does so inefficiently.
  30  *
  31  * @internal documentation reviewed 15 Mar 2010
  32  */
  33 class Title {
  34         /** @name Static cache variables */
  35         // @{
  36         static private $titleCache = array();
  37         // @}
  38
  39         /**
  40          * Title::newFromText maintains a cache to avoid expensive re-normalization of
  41          * commonly used titles. On a batch operation this can become a memory leak
  42          * if not bounded. After hitting this many titles reset the cache.
  43          */
  44         const CACHE_MAX = 1000;
  45
  46         /**
  47          * Used to be GAID_FOR_UPDATE define. Used with getArticleID() and friends
  48          * to use the master DB
  49          */
  50         const GAID_FOR_UPDATE = 1;
  51
  52         /**
  53          * @name Private member variables
  54          * Please use the accessor functions instead.
  55          * @private
  56          */
  57         // @{
  58
  59         var $mTextform = '';              // /< Text form (spaces not underscores) of the main part
  60         var $mUrlform = '';               // /< URL-encoded form of the main part
  61         var $mDbkeyform = '';             // /< Main part with underscores
  62         var $mUserCaseDBKey;              // /< DB key with the initial letter in the case specified by the user
  63         var $mNamespace = NS_MAIN;        // /< Namespace index, i.e. one of the NS_xxxx constants
  64         var $mInterwiki = '';             // /< Interwiki prefix (or null string)
  65         var $mFragment;                   // /< Title fragment (i.e. the bit after the #)
  66         var $mArticleID = -1;             // /< Article ID, fetched from the link cache on demand
  67         var $mLatestID = false;           // /< ID of most recent revision
  68         var $mContentModel = false;       // /< ID of the page's content model, i.e. one of the CONTENT_MODEL_XXX constants
  69         private $mEstimateRevisions;      // /< Estimated number of revisions; null of not loaded
  70         var $mRestrictions = array();     // /< Array of groups allowed to edit this article
  71         var $mOldRestrictions = false;
  72         var $mCascadeRestriction;         ///< Cascade restrictions on this page to included templates and images?
  73         var $mCascadingRestrictions;      // Caching the results of getCascadeProtectionSources
  74         var $mRestrictionsExpiry = array(); ///< When do the restrictions on this page expire?
  75         var $mHasCascadingRestrictions;   ///< Are cascading restrictions in effect on this page?
  76         var $mCascadeSources;             ///< Where are the cascading restrictions coming from on this page?
  77         var $mRestrictionsLoaded = false; ///< Boolean for initialisation on demand
  78         var $mPrefixedText;               ///< Text form including namespace/interwiki, initialised on demand
  79         var $mTitleProtection;            ///< Cached value for getTitleProtection (create protection)
  80         # Don't change the following default, NS_MAIN is hardcoded in several
  81         # places.  See bug 696.
  82         var $mDefaultNamespace = NS_MAIN; // /< Namespace index when there is no namespace
  83                                                                           # Zero except in {{transclusion}} tags
  84         var $mWatched = null;             // /< Is $wgUser watching this page? null if unfilled, accessed through userIsWatching()
  85         var $mLength = -1;                // /< The page length, 0 for special pages
  86         var $mRedirect = null;            // /< Is the article at this title a redirect?
  87         var $mNotificationTimestamp = array(); // /< Associative array of user ID -> timestamp/false
  88         var $mHasSubpage;                 // /< Whether a page has any subpages
  89         // @}
  90
  91
  92         /**
  93          * Constructor
  94          */
  95         /*protected*/ function __construct() { }
  96
  97         /**
  98          * Create a new Title from a prefixed DB key
  99          *
 100          * @param $key String the database key, which has underscores
 101          *      instead of spaces, possibly including namespace and
 102          *      interwiki prefixes
 103          * @return Title, or NULL on an error
 104          */
 105         public static function newFromDBkey( $key ) {
 106                 $t = new Title();
 107                 $t->mDbkeyform = $key;
 108                 if ( $t->secureAndSplit() ) {
 109                         return $t;
 110                 } else {
 111                         return null;
 112                 }
 113         }
 114
 115         /**
 116          * Create a new Title from text, such as what one would find in a link. De-
 117          * codes any HTML entities in the text.
 118          *
 119          * @param $text String the link text; spaces, prefixes, and an
 120          *   initial ':' indicating the main namespace are accepted.
 121          * @param $defaultNamespace Int the namespace to use if none is speci-
 122          *   fied by a prefix.  If you want to force a specific namespace even if
 123          *   $text might begin with a namespace prefix, use makeTitle() or
 124          *   makeTitleSafe().
 125          * @throws MWException
 126          * @return Title|null - Title or null on an error.
 127          */
 128         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 129                 if ( is_object( $text ) ) {
 130                         throw new MWException( 'Title::newFromText given an object' );
 131                 }
 132
 133                 /**
 134                  * Wiki pages often contain multiple links to the same page.
 135                  * Title normalization and parsing can become expensive on
 136                  * pages with many links, so we can save a little time by
 137                  * caching them.
 138                  *
 139                  * In theory these are value objects and won't get changed...
 140                  */
 141                 if ( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 142                         return Title::$titleCache[$text];
 143                 }
 144
 145                 # Convert things like &eacute; &#257; or &#x3017; into normalized (bug 14952) text
 146                 $filteredText = Sanitizer::decodeCharReferencesAndNormalize( $text );
 147
 148                 $t = new Title();
 149                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 150                 $t->mDefaultNamespace = $defaultNamespace;
 151
 152                 static $cachedcount = 0 ;
 153                 if ( $t->secureAndSplit() ) {
 154                         if ( $defaultNamespace == NS_MAIN ) {
 155                                 if ( $cachedcount >= self::CACHE_MAX ) {
 156                                         # Avoid memory leaks on mass operations...
 157                                         Title::$titleCache = array();
 158                                         $cachedcount = 0;
 159                                 }
 160                                 $cachedcount++;
 161                                 Title::$titleCache[$text] =& $t;
 162                         }
 163                         return $t;
 164                 } else {
 165                         $ret = null;
 166                         return $ret;
 167                 }
 168         }
 169
 170         /**
 171          * THIS IS NOT THE FUNCTION YOU WANT. Use Title::newFromText().
 172          *
 173          * Example of wrong and broken code:
 174          * $title = Title::newFromURL( $wgRequest->getVal( 'title' ) );
 175          *
 176          * Example of right code:
 177          * $title = Title::newFromText( $wgRequest->getVal( 'title' ) );
 178          *
 179          * Create a new Title from URL-encoded text. Ensures that
 180          * the given title's length does not exceed the maximum.
 181          *
 182          * @param $url String the title, as might be taken from a URL
 183          * @return Title the new object, or NULL on an error
 184          */
 185         public static function newFromURL( $url ) {
 186                 $t = new Title();
 187
 188                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 189                 # but some URLs used it as a space replacement and they still come
 190                 # from some external search tools.
 191                 if ( strpos( self::legalChars(), '+' ) === false ) {
 192                         $url = str_replace( '+', ' ', $url );
 193                 }
 194
 195                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 196                 if ( $t->secureAndSplit() ) {
 197                         return $t;
 198                 } else {
 199                         return null;
 200                 }
 201         }
 202
 203         /**
 204          * Returns a list of fields that are to be selected for initializing Title objects or LinkCache entries.
 205          * Uses $wgContentHandlerUseDB to determine whether to include page_content_model.
 206          *
 207          * @return array
 208          */
 209         protected static function getSelectFields() {
 210                 global $wgContentHandlerUseDB;
 211
 212                 $fields = array(
 213                         'page_namespace', 'page_title', 'page_id',
 214                         'page_len', 'page_is_redirect', 'page_latest',
 215                 );
 216
 217                 if ( $wgContentHandlerUseDB ) {
 218                         $fields[] = 'page_content_model';
 219                 }
 220
 221                 return $fields;
 222         }
 223
 224         /**
 225          * Create a new Title from an article ID
 226          *
 227          * @param $id Int the page_id corresponding to the Title to create
 228          * @param $flags Int use Title::GAID_FOR_UPDATE to use master
 229          * @return Title the new object, or NULL on an error
 230          */
 231         public static function newFromID( $id, $flags = 0 ) {
 232                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
 233                 $row = $db->selectRow(
 234                         'page',
 235                         self::getSelectFields(),
 236                         array( 'page_id' => $id ),
 237                         __METHOD__
 238                 );
 239                 if ( $row !== false ) {
 240                         $title = Title::newFromRow( $row );
 241                 } else {
 242                         $title = null;
 243                 }
 244                 return $title;
 245         }
 246
 247         /**
 248          * Make an array of titles from an array of IDs
 249          *
 250          * @param $ids Array of Int Array of IDs
 251          * @return Array of Titles
 252          */
 253         public static function newFromIDs( $ids ) {
 254                 if ( !count( $ids ) ) {
 255                         return array();
 256                 }
 257                 $dbr = wfGetDB( DB_SLAVE );
 258
 259                 $res = $dbr->select(
 260                         'page',
 261                         self::getSelectFields(),
 262                         array( 'page_id' => $ids ),
 263                         __METHOD__
 264                 );
 265
 266                 $titles = array();
 267                 foreach ( $res as $row ) {
 268                         $titles[] = Title::newFromRow( $row );
 269                 }
 270                 return $titles;
 271         }
 272
 273         /**
 274          * Make a Title object from a DB row
 275          *
 276          * @param $row Object database row (needs at least page_title,page_namespace)
 277          * @return Title corresponding Title
 278          */
 279         public static function newFromRow( $row ) {
 280                 $t = self::makeTitle( $row->page_namespace, $row->page_title );
 281                 $t->loadFromRow( $row );
 282                 return $t;
 283         }
 284
 285         /**
 286          * Load Title object fields from a DB row.
 287          * If false is given, the title will be treated as non-existing.
 288          *
 289          * @param $row Object|bool database row
 290          */
 291         public function loadFromRow( $row ) {
 292                 if ( $row ) { // page found
 293                         if ( isset( $row->page_id ) )
 294                                 $this->mArticleID = (int)$row->page_id;
 295                         if ( isset( $row->page_len ) )
 296                                 $this->mLength = (int)$row->page_len;
 297                         if ( isset( $row->page_is_redirect ) )
 298                                 $this->mRedirect = (bool)$row->page_is_redirect;
 299                         if ( isset( $row->page_latest ) )
 300                                 $this->mLatestID = (int)$row->page_latest;
 301                         if ( isset( $row->page_content_model ) )
 302                                 $this->mContentModel = strval( $row->page_content_model );
 303                         else
 304                                 $this->mContentModel = false; # initialized lazily in getContentModel()
 305                 } else { // page not found
 306                         $this->mArticleID = 0;
 307                         $this->mLength = 0;
 308                         $this->mRedirect = false;
 309                         $this->mLatestID = 0;
 310                         $this->mContentModel = false; # initialized lazily in getContentModel()
 311                 }
 312         }
 313
 314         /**
 315          * Create a new Title from a namespace index and a DB key.
 316          * It's assumed that $ns and $title are *valid*, for instance when
 317          * they came directly from the database or a special page name.
 318          * For convenience, spaces are converted to underscores so that
 319          * eg user_text fields can be used directly.
 320          *
 321          * @param $ns Int the namespace of the article
 322          * @param $title String the unprefixed database key form
 323          * @param $fragment String the link fragment (after the "#")
 324          * @param $interwiki String the interwiki prefix
 325          * @return Title the new object
 326          */
 327         public static function &makeTitle( $ns, $title, $fragment = '', $interwiki = '' ) {
 328                 $t = new Title();
 329                 $t->mInterwiki = $interwiki;
 330                 $t->mFragment = $fragment;
 331                 $t->mNamespace = $ns = intval( $ns );
 332                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 333                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 334                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 335                 $t->mTextform = str_replace( '_', ' ', $title );
 336                 $t->mContentModel = false; # initialized lazily in getContentModel()
 337                 return $t;
 338         }
 339
 340         /**
 341          * Create a new Title from a namespace index and a DB key.
 342          * The parameters will be checked for validity, which is a bit slower
 343          * than makeTitle() but safer for user-provided data.
 344          *
 345          * @param $ns Int the namespace of the article
 346          * @param $title String database key form
 347          * @param $fragment String the link fragment (after the "#")
 348          * @param $interwiki String interwiki prefix
 349          * @return Title the new object, or NULL on an error
 350          */
 351         public static function makeTitleSafe( $ns, $title, $fragment = '', $interwiki = '' ) {
 352                 if ( !MWNamespace::exists( $ns ) ) {
 353                         return null;
 354                 }
 355
 356                 $t = new Title();
 357                 $t->mDbkeyform = Title::makeName( $ns, $title, $fragment, $interwiki );
 358                 if ( $t->secureAndSplit() ) {
 359                         return $t;
 360                 } else {
 361                         return null;
 362                 }
 363         }
 364
 365         /**
 366          * Create a new Title for the Main Page
 367          *
 368          * @return Title the new object
 369          */
 370         public static function newMainPage() {
 371                 $title = Title::newFromText( wfMessage( 'mainpage' )->inContentLanguage()->text() );
 372                 // Don't give fatal errors if the message is broken
 373                 if ( !$title ) {
 374                         $title = Title::newFromText( 'Main Page' );
 375                 }
 376                 return $title;
 377         }
 378
 379         /**
 380          * Extract a redirect destination from a string and return the
 381          * Title, or null if the text doesn't contain a valid redirect
 382          * This will only return the very next target, useful for
 383          * the redirect table and other checks that don't need full recursion
 384          *
 385          * @param $text String: Text with possible redirect
 386          * @return Title: The corresponding Title
 387          * @deprecated since 1.21, use Content::getRedirectTarget instead.
 388          */
 389         public static function newFromRedirect( $text ) {
 390                 $content = ContentHandler::makeContent( $text, null, CONTENT_MODEL_WIKITEXT );
 391                 return $content->getRedirectTarget();
 392         }
 393
 394         /**
 395          * Extract a redirect destination from a string and return the
 396          * Title, or null if the text doesn't contain a valid redirect
 397          * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
 398          * in order to provide (hopefully) the Title of the final destination instead of another redirect
 399          *
 400          * @param $text String Text with possible redirect
 401          * @return Title
 402          * @deprecated since 1.21, use Content::getUltimateRedirectTarget instead.
 403          */
 404         public static function newFromRedirectRecurse( $text ) {
 405                 $content = ContentHandler::makeContent( $text, null, CONTENT_MODEL_WIKITEXT );
 406                 return $content->getUltimateRedirectTarget();
 407         }
 408
 409         /**
 410          * Extract a redirect destination from a string and return an
 411          * array of Titles, or null if the text doesn't contain a valid redirect
 412          * The last element in the array is the final destination after all redirects
 413          * have been resolved (up to $wgMaxRedirects times)
 414          *
 415          * @param $text String Text with possible redirect
 416          * @return Array of Titles, with the destination last
 417          * @deprecated since 1.21, use Content::getRedirectChain instead.
 418          */
 419         public static function newFromRedirectArray( $text ) {
 420                 $content = ContentHandler::makeContent( $text, null, CONTENT_MODEL_WIKITEXT );
 421                 return $content->getRedirectChain();
 422         }
 423
 424         /**
 425          * Get the prefixed DB key associated with an ID
 426          *
 427          * @param $id Int the page_id of the article
 428          * @return Title an object representing the article, or NULL if no such article was found
 429          */
 430         public static function nameOf( $id ) {
 431                 $dbr = wfGetDB( DB_SLAVE );
 432
 433                 $s = $dbr->selectRow(
 434                         'page',
 435                         array( 'page_namespace', 'page_title' ),
 436                         array( 'page_id' => $id ),
 437                         __METHOD__
 438                 );
 439                 if ( $s === false ) {
 440                         return null;
 441                 }
 442
 443                 $n = self::makeName( $s->page_namespace, $s->page_title );
 444                 return $n;
 445         }
 446
 447         /**
 448          * Get a regex character class describing the legal characters in a link
 449          *
 450          * @return String the list of characters, not delimited
 451          */
 452         public static function legalChars() {
 453                 global $wgLegalTitleChars;
 454                 return $wgLegalTitleChars;
 455         }
 456
 457         /**
 458          * Returns a simple regex that will match on characters and sequences invalid in titles.
 459          * Note that this doesn't pick up many things that could be wrong with titles, but that
 460          * replacing this regex with something valid will make many titles valid.
 461          *
 462          * @return String regex string
 463          */
 464         static function getTitleInvalidRegex() {
 465                 static $rxTc = false;
 466                 if ( !$rxTc ) {
 467                         # Matching titles will be held as illegal.
 468                         $rxTc = '/' .
 469                                 # Any character not allowed is forbidden...
 470                                 '[^' . self::legalChars() . ']' .
 471                                 # URL percent encoding sequences interfere with the ability
 472                                 # to round-trip titles -- you can't link to them consistently.
 473                                 '|%[0-9A-Fa-f]{2}' .
 474                                 # XML/HTML character references produce similar issues.
 475                                 '|&[A-Za-z0-9\x80-\xff]+;' .
 476                                 '|&#[0-9]+;' .
 477                                 '|&#x[0-9A-Fa-f]+;' .
 478                                 '/S';
 479                 }
 480
 481                 return $rxTc;
 482         }
 483
 484         /**
 485          * Get a string representation of a title suitable for
 486          * including in a search index
 487          *
 488          * @param $ns Int a namespace index
 489          * @param $title String text-form main part
 490          * @return String a stripped-down title string ready for the search index
 491          */
 492         public static function indexTitle( $ns, $title ) {
 493                 global $wgContLang;
 494
 495                 $lc = SearchEngine::legalSearchChars() . '&#;';
 496                 $t = $wgContLang->normalizeForSearch( $title );
 497                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 498                 $t = $wgContLang->lc( $t );
 499
 500                 # Handle 's, s'
 501                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 502                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 503
 504                 $t = preg_replace( "/\\s+/", ' ', $t );
 505
 506                 if ( $ns == NS_FILE ) {
 507                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 508                 }
 509                 return trim( $t );
 510         }
 511
 512         /**
 513          * Make a prefixed DB key from a DB key and a namespace index
 514          *
 515          * @param $ns Int numerical representation of the namespace
 516          * @param $title String the DB key form the title
 517          * @param $fragment String The link fragment (after the "#")
 518          * @param $interwiki String The interwiki prefix
 519          * @return String the prefixed form of the title
 520          */
 521         public static function makeName( $ns, $title, $fragment = '', $interwiki = '' ) {
 522                 global $wgContLang;
 523
 524                 $namespace = $wgContLang->getNsText( $ns );
 525                 $name = $namespace == '' ? $title : "$namespace:$title";
 526                 if ( strval( $interwiki ) != '' ) {
 527                         $name = "$interwiki:$name";
 528                 }
 529                 if ( strval( $fragment ) != '' ) {
 530                         $name .= '#' . $fragment;
 531                 }
 532                 return $name;
 533         }
 534
 535         /**
 536          * Escape a text fragment, say from a link, for a URL
 537          *
 538          * @param $fragment string containing a URL or link fragment (after the "#")
 539          * @return String: escaped string
 540          */
 541         static function escapeFragmentForURL( $fragment ) {
 542                 # Note that we don't urlencode the fragment.  urlencoded Unicode
 543                 # fragments appear not to work in IE (at least up to 7) or in at least
 544                 # one version of Opera 9.x.  The W3C validator, for one, doesn't seem
 545                 # to care if they aren't encoded.
 546                 return Sanitizer::escapeId( $fragment, 'noninitial' );
 547         }
 548
 549         /**
 550          * Callback for usort() to do title sorts by (namespace, title)
 551          *
 552          * @param $a Title
 553          * @param $b Title
 554          *
 555          * @return Integer: result of string comparison, or namespace comparison
 556          */
 557         public static function compare( $a, $b ) {
 558                 if ( $a->getNamespace() == $b->getNamespace() ) {
 559                         return strcmp( $a->getText(), $b->getText() );
 560                 } else {
 561                         return $a->getNamespace() - $b->getNamespace();
 562                 }
 563         }
 564
 565         /**
 566          * Determine whether the object refers to a page within
 567          * this project.
 568          *
 569          * @return Bool TRUE if this is an in-project interwiki link or a wikilink, FALSE otherwise
 570          */
 571         public function isLocal() {
 572                 if ( $this->mInterwiki != '' ) {
 573                         return Interwiki::fetch( $this->mInterwiki )->isLocal();
 574                 } else {
 575                         return true;
 576                 }
 577         }
 578
 579         /**
 580          * Is this Title interwiki?
 581          *
 582          * @return Bool
 583          */
 584         public function isExternal() {
 585                 return ( $this->mInterwiki != '' );
 586         }
 587
 588         /**
 589          * Get the interwiki prefix (or null string)
 590          *
 591          * @return String Interwiki prefix
 592          */
 593         public function getInterwiki() {
 594                 return $this->mInterwiki;
 595         }
 596
 597         /**
 598          * Determine whether the object refers to a page within
 599          * this project and is transcludable.
 600          *
 601          * @return Bool TRUE if this is transcludable
 602          */
 603         public function isTrans() {
 604                 if ( $this->mInterwiki == '' ) {
 605                         return false;
 606                 }
 607
 608                 return Interwiki::fetch( $this->mInterwiki )->isTranscludable();
 609         }
 610
 611         /**
 612          * Returns the DB name of the distant wiki which owns the object.
 613          *
 614          * @return String the DB name
 615          */
 616         public function getTransWikiID() {
 617                 if ( $this->mInterwiki == '' ) {
 618                         return false;
 619                 }
 620
 621                 return Interwiki::fetch( $this->mInterwiki )->getWikiID();
 622         }
 623
 624         /**
 625          * Get the text form (spaces not underscores) of the main part
 626          *
 627          * @return String Main part of the title
 628          */
 629         public function getText() {
 630                 return $this->mTextform;
 631         }
 632
 633         /**
 634          * Get the URL-encoded form of the main part
 635          *
 636          * @return String Main part of the title, URL-encoded
 637          */
 638         public function getPartialURL() {
 639                 return $this->mUrlform;
 640         }
 641
 642         /**
 643          * Get the main part with underscores
 644          *
 645          * @return String: Main part of the title, with underscores
 646          */
 647         public function getDBkey() {
 648                 return $this->mDbkeyform;
 649         }
 650
 651         /**
 652          * Get the DB key with the initial letter case as specified by the user
 653          *
 654          * @return String DB key
 655          */
 656         function getUserCaseDBKey() {
 657                 return $this->mUserCaseDBKey;
 658         }
 659
 660         /**
 661          * Get the namespace index, i.e. one of the NS_xxxx constants.
 662          *
 663          * @return Integer: Namespace index
 664          */
 665         public function getNamespace() {
 666                 return $this->mNamespace;
 667         }
 668
 669         /**
 670          * Get the page's content model id, see the CONTENT_MODEL_XXX constants.
 671          *
 672          * @return String: Content model id
 673          */
 674         public function getContentModel() {
 675                 if ( !$this->mContentModel ) {
 676                         $linkCache = LinkCache::singleton();
 677                         $this->mContentModel = $linkCache->getGoodLinkFieldObj( $this, 'model' );
 678                 }
 679
 680                 if ( !$this->mContentModel ) {
 681                         $this->mContentModel = ContentHandler::getDefaultModelFor( $this );
 682                 }
 683
 684                 if( !$this->mContentModel ) {
 685                         throw new MWException( "failed to determin content model!" );
 686                 }
 687
 688                 return $this->mContentModel;
 689         }
 690
 691         /**
 692          * Convenience method for checking a title's content model name
 693          *
 694          * @param String $id The content model ID (use the CONTENT_MODEL_XXX constants).
 695          * @return Boolean true if $this->getContentModel() == $id
 696          */
 697         public function hasContentModel( $id ) {
 698                 return $this->getContentModel() == $id;
 699         }
 700
 701         /**
 702          * Get the namespace text
 703          *
 704          * @return String: Namespace text
 705          */
 706         public function getNsText() {
 707                 global $wgContLang;
 708
 709                 if ( $this->mInterwiki != '' ) {
 710                         // This probably shouldn't even happen. ohh man, oh yuck.
 711                         // But for interwiki transclusion it sometimes does.
 712                         // Shit. Shit shit shit.
 713                         //
 714                         // Use the canonical namespaces if possible to try to
 715                         // resolve a foreign namespace.
 716                         if ( MWNamespace::exists( $this->mNamespace ) ) {
 717                                 return MWNamespace::getCanonicalName( $this->mNamespace );
 718                         }
 719                 }
 720
 721                 if ( $wgContLang->needsGenderDistinction() &&
 722                                 MWNamespace::hasGenderDistinction( $this->mNamespace ) ) {
 723                         $gender = GenderCache::singleton()->getGenderOf( $this->getText(), __METHOD__ );
 724                         return $wgContLang->getGenderNsText( $this->mNamespace, $gender );
 725                 }
 726
 727                 return $wgContLang->getNsText( $this->mNamespace );
 728         }
 729
 730         /**
 731          * Get the namespace text of the subject (rather than talk) page
 732          *
 733          * @return String Namespace text
 734          */
 735         public function getSubjectNsText() {
 736                 global $wgContLang;
 737                 return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
 738         }
 739
 740         /**
 741          * Get the namespace text of the talk page
 742          *
 743          * @return String Namespace text
 744          */
 745         public function getTalkNsText() {
 746                 global $wgContLang;
 747                 return( $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) ) );
 748         }
 749
 750         /**
 751          * Could this title have a corresponding talk page?
 752          *
 753          * @return Bool TRUE or FALSE
 754          */
 755         public function canTalk() {
 756                 return( MWNamespace::canTalk( $this->mNamespace ) );
 757         }
 758
 759         /**
 760          * Is this in a namespace that allows actual pages?
 761          *
 762          * @return Bool
 763          * @internal note -- uses hardcoded namespace index instead of constants
 764          */
 765         public function canExist() {
 766                 return $this->mNamespace >= NS_MAIN;
 767         }
 768
 769         /**
 770          * Can this title be added to a user's watchlist?
 771          *
 772          * @return Bool TRUE or FALSE
 773          */
 774         public function isWatchable() {
 775                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
 776         }
 777
 778         /**
 779          * Returns true if this is a special page.
 780          *
 781          * @return boolean
 782          */
 783         public function isSpecialPage() {
 784                 return $this->getNamespace() == NS_SPECIAL;
 785         }
 786
 787         /**
 788          * Returns true if this title resolves to the named special page
 789          *
 790          * @param $name String The special page name
 791          * @return boolean
 792          */
 793         public function isSpecial( $name ) {
 794                 if ( $this->isSpecialPage() ) {
 795                         list( $thisName, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $this->getDBkey() );
 796                         if ( $name == $thisName ) {
 797                                 return true;
 798                         }
 799                 }
 800                 return false;
 801         }
 802
 803         /**
 804          * If the Title refers to a special page alias which is not the local default, resolve
 805          * the alias, and localise the name as necessary.  Otherwise, return $this
 806          *
 807          * @return Title
 808          */
 809         public function fixSpecialName() {
 810                 if ( $this->isSpecialPage() ) {
 811                         list( $canonicalName, $par ) = SpecialPageFactory::resolveAlias( $this->mDbkeyform );
 812                         if ( $canonicalName ) {
 813                                 $localName = SpecialPageFactory::getLocalNameFor( $canonicalName, $par );
 814                                 if ( $localName != $this->mDbkeyform ) {
 815                                         return Title::makeTitle( NS_SPECIAL, $localName );
 816                                 }
 817                         }
 818                 }
 819                 return $this;
 820         }
 821
 822         /**
 823          * Returns true if the title is inside the specified namespace.
 824          *
 825          * Please make use of this instead of comparing to getNamespace()
 826          * This function is much more resistant to changes we may make
 827          * to namespaces than code that makes direct comparisons.
 828          * @param $ns int The namespace
 829          * @return bool
 830          * @since 1.19
 831          */
 832         public function inNamespace( $ns ) {
 833                 return MWNamespace::equals( $this->getNamespace(), $ns );
 834         }
 835
 836         /**
 837          * Returns true if the title is inside one of the specified namespaces.
 838          *
 839          * @param ...$namespaces The namespaces to check for
 840          * @return bool
 841          * @since 1.19
 842          */
 843         public function inNamespaces( /* ... */ ) {
 844                 $namespaces = func_get_args();
 845                 if ( count( $namespaces ) > 0 && is_array( $namespaces[0] ) ) {
 846                         $namespaces = $namespaces[0];
 847                 }
 848
 849                 foreach ( $namespaces as $ns ) {
 850                         if ( $this->inNamespace( $ns ) ) {
 851                                 return true;
 852                         }
 853                 }
 854
 855                 return false;
 856         }
 857
 858         /**
 859          * Returns true if the title has the same subject namespace as the
 860          * namespace specified.
 861          * For example this method will take NS_USER and return true if namespace
 862          * is either NS_USER or NS_USER_TALK since both of them have NS_USER
 863          * as their subject namespace.
 864          *
 865          * This is MUCH simpler than individually testing for equivilance
 866          * against both NS_USER and NS_USER_TALK, and is also forward compatible.
 867          * @since 1.19
 868          * @param $ns int
 869          * @return bool
 870          */
 871         public function hasSubjectNamespace( $ns ) {
 872                 return MWNamespace::subjectEquals( $this->getNamespace(), $ns );
 873         }
 874
 875         /**
 876          * Is this Title in a namespace which contains content?
 877          * In other words, is this a content page, for the purposes of calculating
 878          * statistics, etc?
 879          *
 880          * @return Boolean
 881          */
 882         public function isContentPage() {
 883                 return MWNamespace::isContent( $this->getNamespace() );
 884         }
 885
 886         /**
 887          * Would anybody with sufficient privileges be able to move this page?
 888          * Some pages just aren't movable.
 889          *
 890          * @return Bool TRUE or FALSE
 891          */
 892         public function isMovable() {
 893                 if ( !MWNamespace::isMovable( $this->getNamespace() ) || $this->getInterwiki() != '' ) {
 894                         // Interwiki title or immovable namespace. Hooks don't get to override here
 895                         return false;
 896                 }
 897
 898                 $result = true;
 899                 wfRunHooks( 'TitleIsMovable', array( $this, &$result ) );
 900                 return $result;
 901         }
 902
 903         /**
 904          * Is this the mainpage?
 905          * @note Title::newFromText seams to be sufficiently optimized by the title
 906          * cache that we don't need to over-optimize by doing direct comparisons and
 907          * acidentally creating new bugs where $title->equals( Title::newFromText() )
 908          * ends up reporting something differently than $title->isMainPage();
 909          *
 910          * @since 1.18
 911          * @return Bool
 912          */
 913         public function isMainPage() {
 914                 return $this->equals( Title::newMainPage() );
 915         }
 916
 917         /**
 918          * Is this a subpage?
 919          *
 920          * @return Bool
 921          */
 922         public function isSubpage() {
 923                 return MWNamespace::hasSubpages( $this->mNamespace )
 924                         ? strpos( $this->getText(), '/' ) !== false
 925                         : false;
 926         }
 927
 928         /**
 929          * Is this a conversion table for the LanguageConverter?
 930          *
 931          * @return Bool
 932          */
 933         public function isConversionTable() {
 934                 //@todo: ConversionTable should become a separate content model.
 935
 936                 return $this->getNamespace() == NS_MEDIAWIKI &&
 937                         strpos( $this->getText(), 'Conversiontable/' ) === 0;
 938         }
 939
 940         /**
 941          * Does that page contain wikitext, or it is JS, CSS or whatever?
 942          *
 943          * @return Bool
 944          */
 945         public function isWikitextPage() {
 946                 return $this->hasContentModel( CONTENT_MODEL_WIKITEXT );
 947         }
 948
 949         /**
 950          * Could this page contain custom CSS or JavaScript for the global UI.
 951          * This is generally true for pages in the MediaWiki namespace having CONTENT_MODEL_CSS
 952          * or CONTENT_MODEL_JAVASCRIPT.
 953          *
 954          * This method does *not* return true for per-user JS/CSS. Use isCssJsSubpage() for that!
 955          *
 956          * Note that this method should not return true for pages that contain and show "inactive" CSS or JS.
 957          *
 958          * @return Bool
 959          */
 960         public function isCssOrJsPage() {
 961                 $isCssOrJsPage = NS_MEDIAWIKI == $this->mNamespace
 962                         && ( $this->hasContentModel( CONTENT_MODEL_CSS )
 963                                 || $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
 964
 965                 #NOTE: this hook is also called in ContentHandler::getDefaultModel. It's called here again to make sure
 966                 #      hook funktions can force this method to return true even outside the mediawiki namespace.
 967
 968                 wfRunHooks( 'TitleIsCssOrJsPage', array( $this, &$isCssOrJsPage ) );
 969
 970                 return $isCssOrJsPage;
 971         }
 972
 973         /**
 974          * Is this a .css or .js subpage of a user page?
 975          * @return Bool
 976          */
 977         public function isCssJsSubpage() {
 978                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
 979                                 && ( $this->hasContentModel( CONTENT_MODEL_CSS )
 980                                         || $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) ) );
 981         }
 982
 983         /**
 984          * Trim down a .css or .js subpage title to get the corresponding skin name
 985          *
 986          * @return string containing skin name from .css or .js subpage title
 987          */
 988         public function getSkinFromCssJsSubpage() {
 989                 $subpage = explode( '/', $this->mTextform );
 990                 $subpage = $subpage[ count( $subpage ) - 1 ];
 991                 $lastdot = strrpos( $subpage, '.' );
 992                 if ( $lastdot === false )
 993                         return $subpage; # Never happens: only called for names ending in '.css' or '.js'
 994                 return substr( $subpage, 0, $lastdot );
 995         }
 996
 997         /**
 998          * Is this a .css subpage of a user page?
 999          *
1000          * @return Bool
1001          */
1002         public function isCssSubpage() {
1003                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
1004                         && $this->hasContentModel( CONTENT_MODEL_CSS ) );
1005         }
1006
1007         /**
1008          * Is this a .js subpage of a user page?
1009          *
1010          * @return Bool
1011          */
1012         public function isJsSubpage() {
1013                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
1014                         && $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
1015         }
1016
1017         /**
1018          * Is this a talk page of some sort?
1019          *
1020          * @return Bool
1021          */
1022         public function isTalkPage() {
1023                 return MWNamespace::isTalk( $this->getNamespace() );
1024         }
1025
1026         /**
1027          * Get a Title object associated with the talk page of this article
1028          *
1029          * @return Title the object for the talk page
1030          */
1031         public function getTalkPage() {
1032                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1033         }
1034
1035         /**
1036          * Get a title object associated with the subject page of this
1037          * talk page
1038          *
1039          * @return Title the object for the subject page
1040          */
1041         public function getSubjectPage() {
1042                 // Is this the same title?
1043                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
1044                 if ( $this->getNamespace() == $subjectNS ) {
1045                         return $this;
1046                 }
1047                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
1048         }
1049
1050         /**
1051          * Get the default namespace index, for when there is no namespace
1052          *
1053          * @return Int Default namespace index
1054          */
1055         public function getDefaultNamespace() {
1056                 return $this->mDefaultNamespace;
1057         }
1058
1059         /**
1060          * Get title for search index
1061          *
1062          * @return String a stripped-down title string ready for the
1063          *  search index
1064          */
1065         public function getIndexTitle() {
1066                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
1067         }
1068
1069         /**
1070          * Get the Title fragment (i.e.\ the bit after the #) in text form
1071          *
1072          * @return String Title fragment
1073          */
1074         public function getFragment() {
1075                 return $this->mFragment;
1076         }
1077
1078         /**
1079          * Get the fragment in URL form, including the "#" character if there is one
1080          * @return String Fragment in URL form
1081          */
1082         public function getFragmentForURL() {
1083                 if ( $this->mFragment == '' ) {
1084                         return '';
1085                 } else {
1086                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
1087                 }
1088         }
1089
1090         /**
1091          * Set the fragment for this title. Removes the first character from the
1092          * specified fragment before setting, so it assumes you're passing it with
1093          * an initial "#".
1094          *
1095          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
1096          * Still in active use privately.
1097          *
1098          * @param $fragment String text
1099          */
1100         public function setFragment( $fragment ) {
1101                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
1102         }
1103
1104         /**
1105          * Prefix some arbitrary text with the namespace or interwiki prefix
1106          * of this object
1107          *
1108          * @param $name String the text
1109          * @return String the prefixed text
1110          * @private
1111          */
1112         private function prefix( $name ) {
1113                 $p = '';
1114                 if ( $this->mInterwiki != '' ) {
1115                         $p = $this->mInterwiki . ':';
1116                 }
1117
1118                 if ( 0 != $this->mNamespace ) {
1119                         $p .= $this->getNsText() . ':';
1120                 }
1121                 return $p . $name;
1122         }
1123
1124         /**
1125          * Get the prefixed database key form
1126          *
1127          * @return String the prefixed title, with underscores and
1128          *  any interwiki and namespace prefixes
1129          */
1130         public function getPrefixedDBkey() {
1131                 $s = $this->prefix( $this->mDbkeyform );
1132                 $s = str_replace( ' ', '_', $s );
1133                 return $s;
1134         }
1135
1136         /**
1137          * Get the prefixed title with spaces.
1138          * This is the form usually used for display
1139          *
1140          * @return String the prefixed title, with spaces
1141          */
1142         public function getPrefixedText() {
1143                 // @todo FIXME: Bad usage of empty() ?
1144                 if ( empty( $this->mPrefixedText ) ) {
1145                         $s = $this->prefix( $this->mTextform );
1146                         $s = str_replace( '_', ' ', $s );
1147                         $this->mPrefixedText = $s;
1148                 }
1149                 return $this->mPrefixedText;
1150         }
1151
1152         /**
1153          * Return a string representation of this title
1154          *
1155          * @return String representation of this title
1156          */
1157         public function __toString() {
1158                 return $this->getPrefixedText();
1159         }
1160
1161         /**
1162          * Get the prefixed title with spaces, plus any fragment
1163          * (part beginning with '#')
1164          *
1165          * @return String the prefixed title, with spaces and the fragment, including '#'
1166          */
1167         public function getFullText() {
1168                 $text = $this->getPrefixedText();
1169                 if ( $this->mFragment != '' ) {
1170                         $text .= '#' . $this->mFragment;
1171                 }
1172                 return $text;
1173         }
1174
1175         /**
1176          * Get the root page name text without a namespace, i.e. the leftmost part before any slashes
1177          *
1178          * @par Example:
1179          * @code
1180          * Title::newFromText('User:Foo/Bar/Baz')->getRootText();
1181          * # returns: 'Foo'
1182          * @endcode
1183          *
1184          * @return String Root name
1185          * @since 1.20
1186          */
1187         public function getRootText() {
1188                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1189                         return $this->getText();
1190                 }
1191
1192                 return strtok( $this->getText(), '/' );
1193         }
1194
1195         /**
1196          * Get the root page name title, i.e. the leftmost part before any slashes
1197          *
1198          * @par Example:
1199          * @code
1200          * Title::newFromText('User:Foo/Bar/Baz')->getRootTitle();
1201          * # returns: Title{User:Foo}
1202          * @endcode
1203          *
1204          * @return Title Root title
1205          * @since 1.20
1206          */
1207         public function getRootTitle() {
1208                 return Title::makeTitle( $this->getNamespace(), $this->getRootText() );
1209         }
1210
1211         /**
1212          * Get the base page name without a namespace, i.e. the part before the subpage name
1213          *
1214          * @par Example:
1215          * @code
1216          * Title::newFromText('User:Foo/Bar/Baz')->getBaseText();
1217          * # returns: 'Foo/Bar'
1218          * @endcode
1219          *
1220          * @return String Base name
1221          */
1222         public function getBaseText() {
1223                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1224                         return $this->getText();
1225                 }
1226
1227                 $parts = explode( '/', $this->getText() );
1228                 # Don't discard the real title if there's no subpage involved
1229                 if ( count( $parts ) > 1 ) {
1230                         unset( $parts[count( $parts ) - 1] );
1231                 }
1232                 return implode( '/', $parts );
1233         }
1234
1235         /**
1236          * Get the base page name title, i.e. the part before the subpage name
1237          *
1238          * @par Example:
1239          * @code
1240          * Title::newFromText('User:Foo/Bar/Baz')->getBaseTitle();
1241          * # returns: Title{User:Foo/Bar}
1242          * @endcode
1243          *
1244          * @return Title Base title
1245          * @since 1.20
1246          */
1247         public function getBaseTitle() {
1248                 return Title::makeTitle( $this->getNamespace(), $this->getBaseText() );
1249         }
1250
1251         /**
1252          * Get the lowest-level subpage name, i.e. the rightmost part after any slashes
1253          *
1254          * @par Example:
1255          * @code
1256          * Title::newFromText('User:Foo/Bar/Baz')->getSubpageText();
1257          * # returns: "Baz"
1258          * @endcode
1259          *
1260          * @return String Subpage name
1261          */
1262         public function getSubpageText() {
1263                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1264                         return( $this->mTextform );
1265                 }
1266                 $parts = explode( '/', $this->mTextform );
1267                 return( $parts[count( $parts ) - 1] );
1268         }
1269
1270         /**
1271          * Get the title for a subpage of the current page
1272          *
1273          * @par Example:
1274          * @code
1275          * Title::newFromText('User:Foo/Bar/Baz')->getSubpage("Asdf");
1276          * # returns: Title{User:Foo/Bar/Baz/Asdf}
1277          * @endcode
1278          *
1279          * @param $text String The subpage name to add to the title
1280          * @return Title Subpage title
1281          * @since 1.20
1282          */
1283         public function getSubpage( $text ) {
1284                 return Title::makeTitleSafe( $this->getNamespace(), $this->getText() . '/' . $text );
1285         }
1286
1287         /**
1288          * Get the HTML-escaped displayable text form.
1289          * Used for the title field in <a> tags.
1290          *
1291          * @return String the text, including any prefixes
1292          */
1293         public function getEscapedText() {
1294                 wfDeprecated( __METHOD__, '1.19' );
1295                 return htmlspecialchars( $this->getPrefixedText() );
1296         }
1297
1298         /**
1299          * Get a URL-encoded form of the subpage text
1300          *
1301          * @return String URL-encoded subpage name
1302          */
1303         public function getSubpageUrlForm() {
1304                 $text = $this->getSubpageText();
1305                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
1306                 return( $text );
1307         }
1308
1309         /**
1310          * Get a URL-encoded title (not an actual URL) including interwiki
1311          *
1312          * @return String the URL-encoded form
1313          */
1314         public function getPrefixedURL() {
1315                 $s = $this->prefix( $this->mDbkeyform );
1316                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
1317                 return $s;
1318         }
1319
1320         /**
1321          * Helper to fix up the get{Local,Full,Link,Canonical}URL args
1322          * get{Canonical,Full,Link,Local}URL methods accepted an optional
1323          * second argument named variant. This was deprecated in favor
1324          * of passing an array of option with a "variant" key
1325          * Once $query2 is removed for good, this helper can be dropped
1326          * andthe wfArrayToCGI moved to getLocalURL();
1327          *
1328          * @since 1.19 (r105919)
1329          * @param $query
1330          * @param $query2 bool
1331          * @return String
1332          */
1333         private static function fixUrlQueryArgs( $query, $query2 = false ) {
1334                 if( $query2 !== false ) {
1335                         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" );
1336                 }
1337                 if ( is_array( $query ) ) {
1338                         $query = wfArrayToCGI( $query );
1339                 }
1340                 if ( $query2 ) {
1341                         if ( is_string( $query2 ) ) {
1342                                 // $query2 is a string, we will consider this to be
1343                                 // a deprecated $variant argument and add it to the query
1344                                 $query2 = wfArrayToCGI( array( 'variant' => $query2 ) );
1345                         } else {
1346                                 $query2 = wfArrayToCGI( $query2 );
1347                         }
1348                         // If we have $query content add a & to it first
1349                         if ( $query ) {
1350                                 $query .= '&';
1351                         }
1352                         // Now append the queries together
1353                         $query .= $query2;
1354                 }
1355                 return $query;
1356         }
1357
1358         /**
1359          * Get a real URL referring to this title, with interwiki link and
1360          * fragment
1361          *
1362          * See getLocalURL for the arguments.
1363          *
1364          * @see self::getLocalURL
1365          * @see wfExpandUrl
1366          * @param $proto Protocol type to use in URL
1367          * @return String the URL
1368          */
1369         public function getFullURL( $query = '', $query2 = false, $proto = PROTO_RELATIVE ) {
1370                 $query = self::fixUrlQueryArgs( $query, $query2 );
1371
1372                 # Hand off all the decisions on urls to getLocalURL
1373                 $url = $this->getLocalURL( $query );
1374
1375                 # Expand the url to make it a full url. Note that getLocalURL has the
1376                 # potential to output full urls for a variety of reasons, so we use
1377                 # wfExpandUrl instead of simply prepending $wgServer
1378                 $url = wfExpandUrl( $url, $proto );
1379
1380                 # Finally, add the fragment.
1381                 $url .= $this->getFragmentForURL();
1382
1383                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
1384                 return $url;
1385         }
1386
1387         /**
1388          * Get a URL with no fragment or server name.  If this page is generated
1389          * with action=render, $wgServer is prepended.
1390          *
1391
1392          * @param $query string|array an optional query string,
1393          *   not used for interwiki     links. Can be specified as an associative array as well,
1394          *   e.g., array( 'action' => 'edit' ) (keys and values will be URL-escaped).
1395          *   Some query patterns will trigger various shorturl path replacements.
1396          * @param $query2 Mixed: An optional secondary query array. This one MUST
1397          *   be an array. If a string is passed it will be interpreted as a deprecated
1398          *   variant argument and urlencoded into a variant= argument.
1399          *   This second query argument will be added to the $query
1400          *   The second parameter is deprecated since 1.19. Pass it as a key,value
1401          *   pair in the first parameter array instead.
1402          *
1403          * @return String the URL
1404          */
1405         public function getLocalURL( $query = '', $query2 = false ) {
1406                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
1407
1408                 $query = self::fixUrlQueryArgs( $query, $query2 );
1409
1410                 $interwiki = Interwiki::fetch( $this->mInterwiki );
1411                 if ( $interwiki ) {
1412                         $namespace = $this->getNsText();
1413                         if ( $namespace != '' ) {
1414                                 # Can this actually happen? Interwikis shouldn't be parsed.
1415                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
1416                                 $namespace .= ':';
1417                         }
1418                         $url = $interwiki->getURL( $namespace . $this->getDBkey() );
1419                         $url = wfAppendQuery( $url, $query );
1420                 } else {
1421                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
1422                         if ( $query == '' ) {
1423                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
1424                                 wfRunHooks( 'GetLocalURL::Article', array( &$this, &$url ) );
1425                         } else {
1426                                 global $wgVariantArticlePath, $wgActionPaths;
1427                                 $url = false;
1428                                 $matches = array();
1429
1430                                 if ( !empty( $wgActionPaths ) &&
1431                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
1432                                 {
1433                                         $action = urldecode( $matches[2] );
1434                                         if ( isset( $wgActionPaths[$action] ) ) {
1435                                                 $query = $matches[1];
1436                                                 if ( isset( $matches[4] ) ) {
1437                                                         $query .= $matches[4];
1438                                                 }
1439                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
1440                                                 if ( $query != '' ) {
1441                                                         $url = wfAppendQuery( $url, $query );
1442                                                 }
1443                                         }
1444                                 }
1445
1446                                 if ( $url === false &&
1447                                         $wgVariantArticlePath &&
1448                                         $this->getPageLanguage()->hasVariants() &&
1449                                         preg_match( '/^variant=([^&]*)$/', $query, $matches ) )
1450                                 {
1451                                         $variant = urldecode( $matches[1] );
1452                                         if ( $this->getPageLanguage()->hasVariant( $variant ) ) {
1453                                                 // Only do the variant replacement if the given variant is a valid
1454                                                 // variant for the page's language.
1455                                                 $url = str_replace( '$2', urlencode( $variant ), $wgVariantArticlePath );
1456                                                 $url = str_replace( '$1', $dbkey, $url );
1457                                         }
1458                                 }
1459
1460                                 if ( $url === false ) {
1461                                         if ( $query == '-' ) {
1462                                                 $query = '';
1463                                         }
1464                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
1465                                 }
1466                         }
1467
1468                         wfRunHooks( 'GetLocalURL::Internal', array( &$this, &$url, $query ) );
1469
1470                         // @todo FIXME: This causes breakage in various places when we
1471                         // actually expected a local URL and end up with dupe prefixes.
1472                         if ( $wgRequest->getVal( 'action' ) == 'render' ) {
1473                                 $url = $wgServer . $url;
1474                         }
1475                 }
1476                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
1477                 return $url;
1478         }
1479
1480         /**
1481          * Get a URL that's the simplest URL that will be valid to link, locally,
1482          * to the current Title.  It includes the fragment, but does not include
1483          * the server unless action=render is used (or the link is external).  If
1484          * there's a fragment but the prefixed text is empty, we just return a link
1485          * to the fragment.
1486          *
1487          * The result obviously should not be URL-escaped, but does need to be
1488          * HTML-escaped if it's being output in HTML.
1489          *
1490          * See getLocalURL for the arguments.
1491          *
1492          * @param $proto Protocol to use; setting this will cause a full URL to be used
1493          * @see self::getLocalURL
1494          * @return String the URL
1495          */
1496         public function getLinkURL( $query = '', $query2 = false, $proto = PROTO_RELATIVE ) {
1497                 wfProfileIn( __METHOD__ );
1498                 if ( $this->isExternal() || $proto !== PROTO_RELATIVE ) {
1499                         $ret = $this->getFullURL( $query, $query2, $proto );
1500                 } elseif ( $this->getPrefixedText() === '' && $this->getFragment() !== '' ) {
1501                         $ret = $this->getFragmentForURL();
1502                 } else {
1503                         $ret = $this->getLocalURL( $query, $query2 ) . $this->getFragmentForURL();
1504                 }
1505                 wfProfileOut( __METHOD__ );
1506                 return $ret;
1507         }
1508
1509         /**
1510          * Get an HTML-escaped version of the URL form, suitable for
1511          * using in a link, without a server name or fragment
1512          *
1513          * See getLocalURL for the arguments.
1514          *
1515          * @see self::getLocalURL
1516          * @param $query string
1517          * @param $query2 bool|string
1518          * @return String the URL
1519          */
1520         public function escapeLocalURL( $query = '', $query2 = false ) {
1521                 wfDeprecated( __METHOD__, '1.19' );
1522                 return htmlspecialchars( $this->getLocalURL( $query, $query2 ) );
1523         }
1524
1525         /**
1526          * Get an HTML-escaped version of the URL form, suitable for
1527          * using in a link, including the server name and fragment
1528          *
1529          * See getLocalURL for the arguments.
1530          *
1531          * @see self::getLocalURL
1532          * @return String the URL
1533          */
1534         public function escapeFullURL( $query = '', $query2 = false ) {
1535                 wfDeprecated( __METHOD__, '1.19' );
1536                 return htmlspecialchars( $this->getFullURL( $query, $query2 ) );
1537         }
1538
1539         /**
1540          * Get the URL form for an internal link.
1541          * - Used in various Squid-related code, in case we have a different
1542          * internal hostname for the server from the exposed one.
1543          *
1544          * This uses $wgInternalServer to qualify the path, or $wgServer
1545          * if $wgInternalServer is not set. If the server variable used is
1546          * protocol-relative, the URL will be expanded to http://
1547          *
1548          * See getLocalURL for the arguments.
1549          *
1550          * @see self::getLocalURL
1551          * @return String the URL
1552          */
1553         public function getInternalURL( $query = '', $query2 = false ) {
1554                 global $wgInternalServer, $wgServer;
1555                 $query = self::fixUrlQueryArgs( $query, $query2 );
1556                 $server = $wgInternalServer !== false ? $wgInternalServer : $wgServer;
1557                 $url = wfExpandUrl( $server . $this->getLocalURL( $query ), PROTO_HTTP );
1558                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
1559                 return $url;
1560         }
1561
1562         /**
1563          * Get the URL for a canonical link, for use in things like IRC and
1564          * e-mail notifications. Uses $wgCanonicalServer and the
1565          * GetCanonicalURL hook.
1566          *
1567          * NOTE: Unlike getInternalURL(), the canonical URL includes the fragment
1568          *
1569          * See getLocalURL for the arguments.
1570          *
1571          * @see self::getLocalURL
1572          * @return string The URL
1573          * @since 1.18
1574          */
1575         public function getCanonicalURL( $query = '', $query2 = false ) {
1576                 $query = self::fixUrlQueryArgs( $query, $query2 );
1577                 $url = wfExpandUrl( $this->getLocalURL( $query ) . $this->getFragmentForURL(), PROTO_CANONICAL );
1578                 wfRunHooks( 'GetCanonicalURL', array( &$this, &$url, $query ) );
1579                 return $url;
1580         }
1581
1582         /**
1583          * HTML-escaped version of getCanonicalURL()
1584          *
1585          * See getLocalURL for the arguments.
1586          *
1587          * @see self::getLocalURL
1588          * @since 1.18
1589          * @return string
1590          */
1591         public function escapeCanonicalURL( $query = '', $query2 = false ) {
1592                 wfDeprecated( __METHOD__, '1.19' );
1593                 return htmlspecialchars( $this->getCanonicalURL( $query, $query2 ) );
1594         }
1595
1596         /**
1597          * Get the edit URL for this Title
1598          *
1599          * @return String the URL, or a null string if this is an
1600          *  interwiki link
1601          */
1602         public function getEditURL() {
1603                 if ( $this->mInterwiki != '' ) {
1604                         return '';
1605                 }
1606                 $s = $this->getLocalURL( 'action=edit' );
1607
1608                 return $s;
1609         }
1610
1611         /**
1612          * Is $wgUser watching this page?
1613          *
1614          * @deprecated in 1.20; use User::isWatched() instead.
1615          * @return Bool
1616          */
1617         public function userIsWatching() {
1618                 global $wgUser;
1619
1620                 if ( is_null( $this->mWatched ) ) {
1621                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn() ) {
1622                                 $this->mWatched = false;
1623                         } else {
1624                                 $this->mWatched = $wgUser->isWatched( $this );
1625                         }
1626                 }
1627                 return $this->mWatched;
1628         }
1629
1630         /**
1631          * Can $wgUser read this page?
1632          *
1633          * @deprecated in 1.19; use userCan(), quickUserCan() or getUserPermissionsErrors() instead
1634          * @return Bool
1635          * @todo fold these checks into userCan()
1636          */
1637         public function userCanRead() {
1638                 wfDeprecated( __METHOD__, '1.19' );
1639                 return $this->userCan( 'read' );
1640         }
1641
1642         /**
1643          * Can $user perform $action on this page?
1644          * This skips potentially expensive cascading permission checks
1645          * as well as avoids expensive error formatting
1646          *
1647          * Suitable for use for nonessential UI controls in common cases, but
1648          * _not_ for functional access control.
1649          *
1650          * May provide false positives, but should never provide a false negative.
1651          *
1652          * @param $action String action that permission needs to be checked for
1653          * @param $user User to check (since 1.19); $wgUser will be used if not
1654          *              provided.
1655          * @return Bool
1656          */
1657         public function quickUserCan( $action, $user = null ) {
1658                 return $this->userCan( $action, $user, false );
1659         }
1660
1661         /**
1662          * Can $user perform $action on this page?
1663          *
1664          * @param $action String action that permission needs to be checked for
1665          * @param $user User to check (since 1.19); $wgUser will be used if not
1666          *   provided.
1667          * @param $doExpensiveQueries Bool Set this to false to avoid doing
1668          *   unnecessary queries.
1669          * @return Bool
1670          */
1671         public function userCan( $action, $user = null, $doExpensiveQueries = true ) {
1672                 if ( !$user instanceof User ) {
1673                         global $wgUser;
1674                         $user = $wgUser;
1675                 }
1676                 return !count( $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries, true ) );
1677         }
1678
1679         /**
1680          * Can $user perform $action on this page?
1681          *
1682          * @todo FIXME: This *does not* check throttles (User::pingLimiter()).
1683          *
1684          * @param $action String action that permission needs to be checked for
1685          * @param $user User to check
1686          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary
1687          *   queries by skipping checks for cascading protections and user blocks.
1688          * @param $ignoreErrors Array of Strings Set this to a list of message keys
1689          *   whose corresponding errors may be ignored.
1690          * @return Array of arguments to wfMessage to explain permissions problems.
1691          */
1692         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1693                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1694
1695                 // Remove the errors being ignored.
1696                 foreach ( $errors as $index => $error ) {
1697                         $error_key = is_array( $error ) ? $error[0] : $error;
1698
1699                         if ( in_array( $error_key, $ignoreErrors ) ) {
1700                                 unset( $errors[$index] );
1701                         }
1702                 }
1703
1704                 return $errors;
1705         }
1706
1707         /**
1708          * Permissions checks that fail most often, and which are easiest to test.
1709          *
1710          * @param $action String the action to check
1711          * @param $user User user to check
1712          * @param $errors Array list of current errors
1713          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1714          * @param $short Boolean short circuit on first error
1715          *
1716          * @return Array list of errors
1717          */
1718         private function checkQuickPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1719                 if ( $action == 'create' ) {
1720                         if ( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1721                                  ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1722                                 $errors[] = $user->isAnon() ? array( 'nocreatetext' ) : array( 'nocreate-loggedin' );
1723                         }
1724                 } elseif ( $action == 'move' ) {
1725                         if ( !$user->isAllowed( 'move-rootuserpages' )
1726                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1727                                 // Show user page-specific message only if the user can move other pages
1728                                 $errors[] = array( 'cant-move-user-page' );
1729                         }
1730
1731                         // Check if user is allowed to move files if it's a file
1732                         if ( $this->mNamespace == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1733                                 $errors[] = array( 'movenotallowedfile' );
1734                         }
1735
1736                         if ( !$user->isAllowed( 'move' ) ) {
1737                                 // User can't move anything
1738                                 $userCanMove = User::groupHasPermission( 'user', 'move' );
1739                                 $autoconfirmedCanMove = User::groupHasPermission( 'autoconfirmed', 'move' );
1740                                 if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
1741                                         // custom message if logged-in users without any special rights can move
1742                                         $errors[] = array( 'movenologintext' );
1743                                 } else {
1744                                         $errors[] = array( 'movenotallowed' );
1745                                 }
1746                         }
1747                 } elseif ( $action == 'move-target' ) {
1748                         if ( !$user->isAllowed( 'move' ) ) {
1749                                 // User can't move anything
1750                                 $errors[] = array( 'movenotallowed' );
1751                         } elseif ( !$user->isAllowed( 'move-rootuserpages' )
1752                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1753                                 // Show user page-specific message only if the user can move other pages
1754                                 $errors[] = array( 'cant-move-to-user-page' );
1755                         }
1756                 } elseif ( !$user->isAllowed( $action ) ) {
1757                         $errors[] = $this->missingPermissionError( $action, $short );
1758                 }
1759
1760                 return $errors;
1761         }
1762
1763         /**
1764          * Add the resulting error code to the errors array
1765          *
1766          * @param $errors Array list of current errors
1767          * @param $result Mixed result of errors
1768          *
1769          * @return Array list of errors
1770          */
1771         private function resultToError( $errors, $result ) {
1772                 if ( is_array( $result ) && count( $result ) && !is_array( $result[0] ) ) {
1773                         // A single array representing an error
1774                         $errors[] = $result;
1775                 } elseif ( is_array( $result ) && is_array( $result[0] ) ) {
1776                         // A nested array representing multiple errors
1777                         $errors = array_merge( $errors, $result );
1778                 } elseif ( $result !== '' && is_string( $result ) ) {
1779                         // A string representing a message-id
1780                         $errors[] = array( $result );
1781                 } elseif ( $result === false ) {
1782                         // a generic "We don't want them to do that"
1783                         $errors[] = array( 'badaccess-group0' );
1784                 }
1785                 return $errors;
1786         }
1787
1788         /**
1789          * Check various permission hooks
1790          *
1791          * @param $action String the action to check
1792          * @param $user User user to check
1793          * @param $errors Array list of current errors
1794          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1795          * @param $short Boolean short circuit on first error
1796          *
1797          * @return Array list of errors
1798          */
1799         private function checkPermissionHooks( $action, $user, $errors, $doExpensiveQueries, $short ) {
1800                 // Use getUserPermissionsErrors instead
1801                 $result = '';
1802                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1803                         return $result ? array() : array( array( 'badaccess-group0' ) );
1804                 }
1805                 // Check getUserPermissionsErrors hook
1806                 if ( !wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1807                         $errors = $this->resultToError( $errors, $result );
1808                 }
1809                 // Check getUserPermissionsErrorsExpensive hook
1810                 if ( $doExpensiveQueries && !( $short && count( $errors ) > 0 ) &&
1811                          !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) ) ) {
1812                         $errors = $this->resultToError( $errors, $result );
1813                 }
1814
1815                 return $errors;
1816         }
1817
1818         /**
1819          * Check permissions on special pages & namespaces
1820          *
1821          * @param $action String the action to check
1822          * @param $user User user to check
1823          * @param $errors Array list of current errors
1824          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1825          * @param $short Boolean short circuit on first error
1826          *
1827          * @return Array list of errors
1828          */
1829         private function checkSpecialsAndNSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1830                 # Only 'createaccount' and 'execute' can be performed on
1831                 # special pages, which don't actually exist in the DB.
1832                 $specialOKActions = array( 'createaccount', 'execute', 'read' );
1833                 if ( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions ) ) {
1834                         $errors[] = array( 'ns-specialprotected' );
1835                 }
1836
1837                 # Check $wgNamespaceProtection for restricted namespaces
1838                 if ( $this->isNamespaceProtected( $user ) ) {
1839                         $ns = $this->mNamespace == NS_MAIN ?
1840                                 wfMessage( 'nstab-main' )->text() : $this->getNsText();
1841                         $errors[] = $this->mNamespace == NS_MEDIAWIKI ?
1842                                 array( 'protectedinterface' ) : array( 'namespaceprotected',  $ns );
1843                 }
1844
1845                 return $errors;
1846         }
1847
1848         /**
1849          * Check CSS/JS sub-page permissions
1850          *
1851          * @param $action String the action to check
1852          * @param $user User user to check
1853          * @param $errors Array list of current errors
1854          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1855          * @param $short Boolean short circuit on first error
1856          *
1857          * @return Array list of errors
1858          */
1859         private function checkCSSandJSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1860                 # Protect css/js subpages of user pages
1861                 # XXX: this might be better using restrictions
1862                 # XXX: right 'editusercssjs' is deprecated, for backward compatibility only
1863                 if ( $action != 'patrol' && !$user->isAllowed( 'editusercssjs' )
1864                                 && !preg_match( '/^' . preg_quote( $user->getName(), '/' ) . '\//', $this->mTextform ) ) {
1865                         if ( $this->isCssSubpage() && !$user->isAllowed( 'editusercss' ) ) {
1866                                 $errors[] = array( 'customcssprotected' );
1867                         } elseif ( $this->isJsSubpage() && !$user->isAllowed( 'edituserjs' ) ) {
1868                                 $errors[] = array( 'customjsprotected' );
1869                         }
1870                 }
1871
1872                 return $errors;
1873         }
1874
1875         /**
1876          * Check against page_restrictions table requirements on this
1877          * page. The user must possess all required rights for this
1878          * action.
1879          *
1880          * @param $action String the action to check
1881          * @param $user User user to check
1882          * @param $errors Array list of current errors
1883          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1884          * @param $short Boolean short circuit on first error
1885          *
1886          * @return Array list of errors
1887          */
1888         private function checkPageRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1889                 foreach ( $this->getRestrictions( $action ) as $right ) {
1890                         // Backwards compatibility, rewrite sysop -> protect
1891                         if ( $right == 'sysop' ) {
1892                                 $right = 'protect';
1893                         }
1894                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1895                                 // Users with 'editprotected' permission can edit protected pages
1896                                 // without cascading option turned on.
1897                                 if ( $action != 'edit' || !$user->isAllowed( 'editprotected' )
1898                                         || $this->mCascadeRestriction )
1899                                 {
1900                                         $errors[] = array( 'protectedpagetext', $right );
1901                                 }
1902                         }
1903                 }
1904
1905                 return $errors;
1906         }
1907
1908         /**
1909          * Check restrictions on cascading pages.
1910          *
1911          * @param $action String the action to check
1912          * @param $user User to check
1913          * @param $errors Array list of current errors
1914          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1915          * @param $short Boolean short circuit on first error
1916          *
1917          * @return Array list of errors
1918          */
1919         private function checkCascadingSourcesRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1920                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1921                         # We /could/ use the protection level on the source page, but it's
1922                         # fairly ugly as we have to establish a precedence hierarchy for pages
1923                         # included by multiple cascade-protected pages. So just restrict
1924                         # it to people with 'protect' permission, as they could remove the
1925                         # protection anyway.
1926                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1927                         # Cascading protection depends on more than this page...
1928                         # Several cascading protected pages may include this page...
1929                         # Check each cascading level
1930                         # This is only for protection restrictions, not for all actions
1931                         if ( isset( $restrictions[$action] ) ) {
1932                                 foreach ( $restrictions[$action] as $right ) {
1933                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1934                                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1935                                                 $pages = '';
1936                                                 foreach ( $cascadingSources as $page )
1937                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1938                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1939                                         }
1940                                 }
1941                         }
1942                 }
1943
1944                 return $errors;
1945         }
1946
1947         /**
1948          * Check action permissions not already checked in checkQuickPermissions
1949          *
1950          * @param $action String the action to check
1951          * @param $user User to check
1952          * @param $errors Array list of current errors
1953          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1954          * @param $short Boolean short circuit on first error
1955          *
1956          * @return Array list of errors
1957          */
1958         private function checkActionPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1959                 global $wgDeleteRevisionsLimit, $wgLang;
1960
1961                 if ( $action == 'protect' ) {
1962                         if ( count( $this->getUserPermissionsErrorsInternal( 'edit', $user, $doExpensiveQueries, true ) ) ) {
1963                                 // If they can't edit, they shouldn't protect.
1964                                 $errors[] = array( 'protect-cantedit' );
1965                         }
1966                 } elseif ( $action == 'create' ) {
1967                         $title_protection = $this->getTitleProtection();
1968                         if( $title_protection ) {
1969                                 if( $title_protection['pt_create_perm'] == 'sysop' ) {
1970                                         $title_protection['pt_create_perm'] = 'protect'; // B/C
1971                                 }
1972                                 if( $title_protection['pt_create_perm'] == '' ||
1973                                         !$user->isAllowed( $title_protection['pt_create_perm'] ) )
1974                                 {
1975                                         $errors[] = array( 'titleprotected', User::whoIs( $title_protection['pt_user'] ), $title_protection['pt_reason'] );
1976                                 }
1977                         }
1978                 } elseif ( $action == 'move' ) {
1979                         // Check for immobile pages
1980                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1981                                 // Specific message for this case
1982                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1983                         } elseif ( !$this->isMovable() ) {
1984                                 // Less specific message for rarer cases
1985                                 $errors[] = array( 'immobile-source-page' );
1986                         }
1987                 } elseif ( $action == 'move-target' ) {
1988                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1989                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1990                         } elseif ( !$this->isMovable() ) {
1991                                 $errors[] = array( 'immobile-target-page' );
1992                         }
1993                 } elseif ( $action == 'delete' ) {
1994                         if ( $doExpensiveQueries && $wgDeleteRevisionsLimit
1995                                 && !$this->userCan( 'bigdelete', $user ) && $this->isBigDeletion() )
1996                         {
1997                                 $errors[] = array( 'delete-toobig', $wgLang->formatNum( $wgDeleteRevisionsLimit ) );
1998                         }
1999                 }
2000                 return $errors;
2001         }
2002
2003         /**
2004          * Check that the user isn't blocked from editting.
2005          *
2006          * @param $action String the action to check
2007          * @param $user User to check
2008          * @param $errors Array list of current errors
2009          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
2010          * @param $short Boolean short circuit on first error
2011          *
2012          * @return Array list of errors
2013          */
2014         private function checkUserBlock( $action, $user, $errors, $doExpensiveQueries, $short ) {
2015                 // Account creation blocks handled at userlogin.
2016                 // Unblocking handled in SpecialUnblock
2017                 if( !$doExpensiveQueries || in_array( $action, array( 'createaccount', 'unblock' ) ) ) {
2018                         return $errors;
2019                 }
2020
2021                 global $wgContLang, $wgLang, $wgEmailConfirmToEdit;
2022
2023                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() ) {
2024                         $errors[] = array( 'confirmedittext' );
2025                 }
2026
2027                 if ( ( $action == 'edit' || $action == 'create' ) && !$user->isBlockedFrom( $this ) ) {
2028                         // Don't block the user from editing their own talk page unless they've been
2029                         // explicitly blocked from that too.
2030                 } elseif( $user->isBlocked() && $user->mBlock->prevents( $action ) !== false ) {
2031                         $block = $user->getBlock();
2032
2033                         // This is from OutputPage::blockedPage
2034                         // Copied at r23888 by werdna
2035
2036                         $id = $user->blockedBy();
2037                         $reason = $user->blockedFor();
2038                         if ( $reason == '' ) {
2039                                 $reason = wfMessage( 'blockednoreason' )->text();
2040                         }
2041                         $ip = $user->getRequest()->getIP();
2042
2043                         if ( is_numeric( $id ) ) {
2044                                 $name = User::whoIs( $id );
2045                         } else {
2046                                 $name = $id;
2047                         }
2048
2049                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
2050                         $blockid = $block->getId();
2051                         $blockExpiry = $block->getExpiry();
2052                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $block->mTimestamp ), true );
2053                         if ( $blockExpiry == 'infinity' ) {
2054                                 $blockExpiry = wfMessage( 'infiniteblock' )->text();
2055                         } else {
2056                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
2057                         }
2058
2059                         $intended = strval( $block->getTarget() );
2060
2061                         $errors[] = array( ( $block->mAuto ? 'autoblockedtext' : 'blockedtext' ), $link, $reason, $ip, $name,
2062                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
2063                 }
2064
2065                 return $errors;
2066         }
2067
2068         /**
2069          * Check that the user is allowed to read this page.
2070          *
2071          * @param $action String the action to check
2072          * @param $user User to check
2073          * @param $errors Array list of current errors
2074          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
2075          * @param $short Boolean short circuit on first error
2076          *
2077          * @return Array list of errors
2078          */
2079         private function checkReadPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
2080                 global $wgWhitelistRead, $wgRevokePermissions;
2081                 static $useShortcut = null;
2082
2083                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
2084                 if ( is_null( $useShortcut ) ) {
2085                         $useShortcut = true;
2086                         if ( !User::groupHasPermission( '*', 'read' ) ) {
2087                                 # Not a public wiki, so no shortcut
2088                                 $useShortcut = false;
2089                         } elseif ( !empty( $wgRevokePermissions ) ) {
2090                                 /**
2091                                  * Iterate through each group with permissions being revoked (key not included since we don't care
2092                                  * what the group name is), then check if the read permission is being revoked. If it is, then
2093                                  * we don't use the shortcut below since the user might not be able to read, even though anon
2094                                  * reading is allowed.
2095                                  */
2096                                 foreach ( $wgRevokePermissions as $perms ) {
2097                                         if ( !empty( $perms['read'] ) ) {
2098                                                 # We might be removing the read right from the user, so no shortcut
2099                                                 $useShortcut = false;
2100                                                 break;
2101                                         }
2102                                 }
2103                         }
2104                 }
2105
2106                 $whitelisted = false;
2107                 if ( $useShortcut ) {
2108                         # Shortcut for public wikis, allows skipping quite a bit of code
2109                         $whitelisted = true;
2110                 } elseif ( $user->isAllowed( 'read' ) ) {
2111                         # If the user is allowed to read pages, he is allowed to read all pages
2112                         $whitelisted = true;
2113                 } elseif ( $this->isSpecial( 'Userlogin' )
2114                         || $this->isSpecial( 'ChangePassword' )
2115                         || $this->isSpecial( 'PasswordReset' )
2116                 ) {
2117                         # Always grant access to the login page.
2118                         # Even anons need to be able to log in.
2119                         $whitelisted = true;
2120                 } elseif ( is_array( $wgWhitelistRead ) && count( $wgWhitelistRead ) ) {
2121                         # Time to check the whitelist
2122                         # Only do these checks is there's something to check against
2123                         $name = $this->getPrefixedText();
2124                         $dbName = $this->getPrefixedDBKey();
2125
2126                         // Check for explicit whitelisting with and without underscores
2127                         if ( in_array( $name, $wgWhitelistRead, true ) || in_array( $dbName, $wgWhitelistRead, true ) ) {
2128                                 $whitelisted = true;
2129                         } elseif ( $this->getNamespace() == NS_MAIN ) {
2130                                 # Old settings might have the title prefixed with
2131                                 # a colon for main-namespace pages
2132                                 if ( in_array( ':' . $name, $wgWhitelistRead ) ) {
2133                                         $whitelisted = true;
2134                                 }
2135                         } elseif ( $this->isSpecialPage() ) {
2136                                 # If it's a special page, ditch the subpage bit and check again
2137                                 $name = $this->getDBkey();
2138                                 list( $name, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $name );
2139                                 if ( $name !== false ) {
2140                                         $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
2141                                         if ( in_array( $pure, $wgWhitelistRead, true ) ) {
2142                                                 $whitelisted = true;
2143                                         }
2144                                 }
2145                         }
2146                 }
2147
2148                 if ( !$whitelisted ) {
2149                         # If the title is not whitelisted, give extensions a chance to do so...
2150                         wfRunHooks( 'TitleReadWhitelist', array( $this, $user, &$whitelisted ) );
2151                         if ( !$whitelisted ) {
2152                                 $errors[] = $this->missingPermissionError( $action, $short );
2153                         }
2154                 }
2155
2156                 return $errors;
2157         }
2158
2159         /**
2160          * Get a description array when the user doesn't have the right to perform
2161          * $action (i.e. when User::isAllowed() returns false)
2162          *
2163          * @param $action String the action to check
2164          * @param $short Boolean short circuit on first error
2165          * @return Array list of errors
2166          */
2167         private function missingPermissionError( $action, $short ) {
2168                 // We avoid expensive display logic for quickUserCan's and such
2169                 if ( $short ) {
2170                         return array( 'badaccess-group0' );
2171                 }
2172
2173                 $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
2174                         User::getGroupsWithPermission( $action ) );
2175
2176                 if ( count( $groups ) ) {
2177                         global $wgLang;
2178                         return array(
2179                                 'badaccess-groups',
2180                                 $wgLang->commaList( $groups ),
2181                                 count( $groups )
2182                         );
2183                 } else {
2184                         return array( 'badaccess-group0' );
2185                 }
2186         }
2187
2188         /**
2189          * Can $user perform $action on this page? This is an internal function,
2190          * which checks ONLY that previously checked by userCan (i.e. it leaves out
2191          * checks on wfReadOnly() and blocks)
2192          *
2193          * @param $action String action that permission needs to be checked for
2194          * @param $user User to check
2195          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary queries.
2196          * @param $short Bool Set this to true to stop after the first permission error.
2197          * @return Array of arrays of the arguments to wfMessage to explain permissions problems.
2198          */
2199         protected function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true, $short = false ) {
2200                 wfProfileIn( __METHOD__ );
2201
2202                 # Read has special handling
2203                 if ( $action == 'read' ) {
2204                         $checks = array(
2205                                 'checkPermissionHooks',
2206                                 'checkReadPermissions',
2207                         );
2208                 } else {
2209                         $checks = array(
2210                                 'checkQuickPermissions',
2211                                 'checkPermissionHooks',
2212                                 'checkSpecialsAndNSPermissions',
2213                                 'checkCSSandJSPermissions',
2214                                 'checkPageRestrictions',
2215                                 'checkCascadingSourcesRestrictions',
2216                                 'checkActionPermissions',
2217                                 'checkUserBlock'
2218                         );
2219                 }
2220
2221                 $errors = array();
2222                 while( count( $checks ) > 0 &&
2223                                 !( $short && count( $errors ) > 0 ) ) {
2224                         $method = array_shift( $checks );
2225                         $errors = $this->$method( $action, $user, $errors, $doExpensiveQueries, $short );
2226                 }
2227
2228                 wfProfileOut( __METHOD__ );
2229                 return $errors;
2230         }
2231
2232         /**
2233          * Protect css subpages of user pages: can $wgUser edit
2234          * this page?
2235          *
2236          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2237          * @return Bool
2238          */
2239         public function userCanEditCssSubpage() {
2240                 global $wgUser;
2241                 wfDeprecated( __METHOD__, '1.19' );
2242                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'editusercss' ) )
2243                         || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2244         }
2245
2246         /**
2247          * Protect js subpages of user pages: can $wgUser edit
2248          * this page?
2249          *
2250          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2251          * @return Bool
2252          */
2253         public function userCanEditJsSubpage() {
2254                 global $wgUser;
2255                 wfDeprecated( __METHOD__, '1.19' );
2256                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'edituserjs' ) )
2257                            || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2258         }
2259
2260         /**
2261          * Get a filtered list of all restriction types supported by this wiki.
2262          * @param bool $exists True to get all restriction types that apply to
2263          * titles that do exist, False for all restriction types that apply to
2264          * titles that do not exist
2265          * @return array
2266          */
2267         public static function getFilteredRestrictionTypes( $exists = true ) {
2268                 global $wgRestrictionTypes;
2269                 $types = $wgRestrictionTypes;
2270                 if ( $exists ) {
2271                         # Remove the create restriction for existing titles
2272                         $types = array_diff( $types, array( 'create' ) );
2273                 } else {
2274                         # Only the create and upload restrictions apply to non-existing titles
2275                         $types = array_intersect( $types, array( 'create', 'upload' ) );
2276                 }
2277                 return $types;
2278         }
2279
2280         /**
2281          * Returns restriction types for the current Title
2282          *
2283          * @return array applicable restriction types
2284          */
2285         public function getRestrictionTypes() {
2286                 if ( $this->isSpecialPage() ) {
2287                         return array();
2288                 }
2289
2290                 $types = self::getFilteredRestrictionTypes( $this->exists() );
2291
2292                 if ( $this->getNamespace() != NS_FILE ) {
2293                         # Remove the upload restriction for non-file titles
2294                         $types = array_diff( $types, array( 'upload' ) );
2295                 }
2296
2297                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
2298
2299                 wfDebug( __METHOD__ . ': applicable restrictions to [[' .
2300                         $this->getPrefixedText() . ']] are {' . implode( ',', $types ) . "}\n" );
2301
2302                 return $types;
2303         }
2304
2305         /**
2306          * Is this title subject to title protection?
2307          * Title protection is the one applied against creation of such title.
2308          *
2309          * @return Mixed An associative array representing any existent title
2310          *   protection, or false if there's none.
2311          */
2312         private function getTitleProtection() {
2313                 // Can't protect pages in special namespaces
2314                 if ( $this->getNamespace() < 0 ) {
2315                         return false;
2316                 }
2317
2318                 // Can't protect pages that exist.
2319                 if ( $this->exists() ) {
2320                         return false;
2321                 }
2322
2323                 if ( !isset( $this->mTitleProtection ) ) {
2324                         $dbr = wfGetDB( DB_SLAVE );
2325                         $res = $dbr->select( 'protected_titles', '*',
2326                                 array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2327                                 __METHOD__ );
2328
2329                         // fetchRow returns false if there are no rows.
2330                         $this->mTitleProtection = $dbr->fetchRow( $res );
2331                 }
2332                 return $this->mTitleProtection;
2333         }
2334
2335         /**
2336          * Update the title protection status
2337          *
2338          * @deprecated in 1.19; will be removed in 1.20. Use WikiPage::doUpdateRestrictions() instead.
2339          * @param $create_perm String Permission required for creation
2340          * @param $reason String Reason for protection
2341          * @param $expiry String Expiry timestamp
2342          * @return boolean true
2343          */
2344         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
2345                 wfDeprecated( __METHOD__, '1.19' );
2346
2347                 global $wgUser;
2348
2349                 $limit = array( 'create' => $create_perm );
2350                 $expiry = array( 'create' => $expiry );
2351
2352                 $page = WikiPage::factory( $this );
2353                 $status = $page->doUpdateRestrictions( $limit, $expiry, false, $reason, $wgUser );
2354
2355                 return $status->isOK();
2356         }
2357
2358         /**
2359          * Remove any title protection due to page existing
2360          */
2361         public function deleteTitleProtection() {
2362                 $dbw = wfGetDB( DB_MASTER );
2363
2364                 $dbw->delete(
2365                         'protected_titles',
2366                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2367                         __METHOD__
2368                 );
2369                 $this->mTitleProtection = false;
2370         }
2371
2372         /**
2373          * Is this page "semi-protected" - the *only* protection is autoconfirm?
2374          *
2375          * @param $action String Action to check (default: edit)
2376          * @return Bool
2377          */
2378         public function isSemiProtected( $action = 'edit' ) {
2379                 if ( $this->exists() ) {
2380                         $restrictions = $this->getRestrictions( $action );
2381                         if ( count( $restrictions ) > 0 ) {
2382                                 foreach ( $restrictions as $restriction ) {
2383                                         if ( strtolower( $restriction ) != 'autoconfirmed' ) {
2384                                                 return false;
2385                                         }
2386                                 }
2387                         } else {
2388                                 # Not protected
2389                                 return false;
2390                         }
2391                         return true;
2392                 } else {
2393                         # If it doesn't exist, it can't be protected
2394                         return false;
2395                 }
2396         }
2397
2398         /**
2399          * Does the title correspond to a protected article?
2400          *
2401          * @param $action String the action the page is protected from,
2402          * by default checks all actions.
2403          * @return Bool
2404          */
2405         public function isProtected( $action = '' ) {
2406                 global $wgRestrictionLevels;
2407
2408                 $restrictionTypes = $this->getRestrictionTypes();
2409
2410                 # Special pages have inherent protection
2411                 if( $this->isSpecialPage() ) {
2412                         return true;
2413                 }
2414
2415                 # Check regular protection levels
2416                 foreach ( $restrictionTypes as $type ) {
2417                         if ( $action == $type || $action == '' ) {
2418                                 $r = $this->getRestrictions( $type );
2419                                 foreach ( $wgRestrictionLevels as $level ) {
2420                                         if ( in_array( $level, $r ) && $level != '' ) {
2421                                                 return true;
2422                                         }
2423                                 }
2424                         }
2425                 }
2426
2427                 return false;
2428         }
2429
2430         /**
2431          * Determines if $user is unable to edit this page because it has been protected
2432          * by $wgNamespaceProtection.
2433          *
2434          * @param $user User object to check permissions
2435          * @return Bool
2436          */
2437         public function isNamespaceProtected( User $user ) {
2438                 global $wgNamespaceProtection;
2439
2440                 if ( isset( $wgNamespaceProtection[$this->mNamespace] ) ) {
2441                         foreach ( (array)$wgNamespaceProtection[$this->mNamespace] as $right ) {
2442                                 if ( $right != '' && !$user->isAllowed( $right ) ) {
2443                                         return true;
2444                                 }
2445                         }
2446                 }
2447                 return false;
2448         }
2449
2450         /**
2451          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
2452          *
2453          * @return Bool If the page is subject to cascading restrictions.
2454          */
2455         public function isCascadeProtected() {
2456                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
2457                 return ( $sources > 0 );
2458         }
2459
2460         /**
2461          * Cascading protection: Get the source of any cascading restrictions on this page.
2462          *
2463          * @param $getPages Bool Whether or not to retrieve the actual pages
2464          *        that the restrictions have come from.
2465          * @return Mixed Array of Title objects of the pages from which cascading restrictions
2466          *     have come, false for none, or true if such restrictions exist, but $getPages
2467          *     was not set.  The restriction array is an array of each type, each of which
2468          *     contains a array of unique groups.
2469          */
2470         public function getCascadeProtectionSources( $getPages = true ) {
2471                 global $wgContLang;
2472                 $pagerestrictions = array();
2473
2474                 if ( isset( $this->mCascadeSources ) && $getPages ) {
2475                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
2476                 } elseif ( isset( $this->mHasCascadingRestrictions ) && !$getPages ) {
2477                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
2478                 }
2479
2480                 wfProfileIn( __METHOD__ );
2481
2482                 $dbr = wfGetDB( DB_SLAVE );
2483
2484                 if ( $this->getNamespace() == NS_FILE ) {
2485                         $tables = array( 'imagelinks', 'page_restrictions' );
2486                         $where_clauses = array(
2487                                 'il_to' => $this->getDBkey(),
2488                                 'il_from=pr_page',
2489                                 'pr_cascade' => 1
2490                         );
2491                 } else {
2492                         $tables = array( 'templatelinks', 'page_restrictions' );
2493                         $where_clauses = array(
2494                                 'tl_namespace' => $this->getNamespace(),
2495                                 'tl_title' => $this->getDBkey(),
2496                                 'tl_from=pr_page',
2497                                 'pr_cascade' => 1
2498                         );
2499                 }
2500
2501                 if ( $getPages ) {
2502                         $cols = array( 'pr_page', 'page_namespace', 'page_title',
2503                                                    'pr_expiry', 'pr_type', 'pr_level' );
2504                         $where_clauses[] = 'page_id=pr_page';
2505                         $tables[] = 'page';
2506                 } else {
2507                         $cols = array( 'pr_expiry' );
2508                 }
2509
2510                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
2511
2512                 $sources = $getPages ? array() : false;
2513                 $now = wfTimestampNow();
2514                 $purgeExpired = false;
2515
2516                 foreach ( $res as $row ) {
2517                         $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2518                         if ( $expiry > $now ) {
2519                                 if ( $getPages ) {
2520                                         $page_id = $row->pr_page;
2521                                         $page_ns = $row->page_namespace;
2522                                         $page_title = $row->page_title;
2523                                         $sources[$page_id] = Title::makeTitle( $page_ns, $page_title );
2524                                         # Add groups needed for each restriction type if its not already there
2525                                         # Make sure this restriction type still exists
2526
2527                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
2528                                                 $pagerestrictions[$row->pr_type] = array();
2529                                         }
2530
2531                                         if ( isset( $pagerestrictions[$row->pr_type] ) &&
2532                                                  !in_array( $row->pr_level, $pagerestrictions[$row->pr_type] ) ) {
2533                                                 $pagerestrictions[$row->pr_type][] = $row->pr_level;
2534                                         }
2535                                 } else {
2536                                         $sources = true;
2537                                 }
2538                         } else {
2539                                 // Trigger lazy purge of expired restrictions from the db
2540                                 $purgeExpired = true;
2541                         }
2542                 }
2543                 if ( $purgeExpired ) {
2544                         Title::purgeExpiredRestrictions();
2545                 }
2546
2547                 if ( $getPages ) {
2548                         $this->mCascadeSources = $sources;
2549                         $this->mCascadingRestrictions = $pagerestrictions;
2550                 } else {
2551                         $this->mHasCascadingRestrictions = $sources;
2552                 }
2553
2554                 wfProfileOut( __METHOD__ );
2555                 return array( $sources, $pagerestrictions );
2556         }
2557
2558         /**
2559          * Accessor/initialisation for mRestrictions
2560          *
2561          * @param $action String action that permission needs to be checked for
2562          * @return Array of Strings the array of groups allowed to edit this article
2563          */
2564         public function getRestrictions( $action ) {
2565                 if ( !$this->mRestrictionsLoaded ) {
2566                         $this->loadRestrictions();
2567                 }
2568                 return isset( $this->mRestrictions[$action] )
2569                                 ? $this->mRestrictions[$action]
2570                                 : array();
2571         }
2572
2573         /**
2574          * Get the expiry time for the restriction against a given action
2575          *
2576          * @param $action
2577          * @return String|Bool 14-char timestamp, or 'infinity' if the page is protected forever
2578          *     or not protected at all, or false if the action is not recognised.
2579          */
2580         public function getRestrictionExpiry( $action ) {
2581                 if ( !$this->mRestrictionsLoaded ) {
2582                         $this->loadRestrictions();
2583                 }
2584                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2585         }
2586
2587         /**
2588          * Returns cascading restrictions for the current article
2589          *
2590          * @return Boolean
2591          */
2592         function areRestrictionsCascading() {
2593                 if ( !$this->mRestrictionsLoaded ) {
2594                         $this->loadRestrictions();
2595                 }
2596
2597                 return $this->mCascadeRestriction;
2598         }
2599
2600         /**
2601          * Loads a string into mRestrictions array
2602          *
2603          * @param $res Resource restrictions as an SQL result.
2604          * @param $oldFashionedRestrictions String comma-separated list of page
2605          *        restrictions from page table (pre 1.10)
2606          */
2607         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
2608                 $rows = array();
2609
2610                 foreach ( $res as $row ) {
2611                         $rows[] = $row;
2612                 }
2613
2614                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
2615         }
2616
2617         /**
2618          * Compiles list of active page restrictions from both page table (pre 1.10)
2619          * and page_restrictions table for this existing page.
2620          * Public for usage by LiquidThreads.
2621          *
2622          * @param $rows array of db result objects
2623          * @param $oldFashionedRestrictions string comma-separated list of page
2624          *        restrictions from page table (pre 1.10)
2625          */
2626         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
2627                 global $wgContLang;
2628                 $dbr = wfGetDB( DB_SLAVE );
2629
2630                 $restrictionTypes = $this->getRestrictionTypes();
2631
2632                 foreach ( $restrictionTypes as $type ) {
2633                         $this->mRestrictions[$type] = array();
2634                         $this->mRestrictionsExpiry[$type] = $wgContLang->formatExpiry( '', TS_MW );
2635                 }
2636
2637                 $this->mCascadeRestriction = false;
2638
2639                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2640
2641                 if ( $oldFashionedRestrictions === null ) {
2642                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2643                                 array( 'page_id' => $this->getArticleID() ), __METHOD__ );
2644                 }
2645
2646                 if ( $oldFashionedRestrictions != '' ) {
2647
2648                         foreach ( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2649                                 $temp = explode( '=', trim( $restrict ) );
2650                                 if ( count( $temp ) == 1 ) {
2651                                         // old old format should be treated as edit/move restriction
2652                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2653                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2654                                 } else {
2655                                         $restriction = trim( $temp[1] );
2656                                         if( $restriction != '' ) { //some old entries are empty
2657                                                 $this->mRestrictions[$temp[0]] = explode( ',', $restriction );
2658                                         }
2659                                 }
2660                         }
2661
2662                         $this->mOldRestrictions = true;
2663
2664                 }
2665
2666                 if ( count( $rows ) ) {
2667                         # Current system - load second to make them override.
2668                         $now = wfTimestampNow();
2669                         $purgeExpired = false;
2670
2671                         # Cycle through all the restrictions.
2672                         foreach ( $rows as $row ) {
2673
2674                                 // Don't take care of restrictions types that aren't allowed
2675                                 if ( !in_array( $row->pr_type, $restrictionTypes ) )
2676                                         continue;
2677
2678                                 // This code should be refactored, now that it's being used more generally,
2679                                 // But I don't really see any harm in leaving it in Block for now -werdna
2680                                 $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2681
2682                                 // Only apply the restrictions if they haven't expired!
2683                                 if ( !$expiry || $expiry > $now ) {
2684                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2685                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2686
2687                                         $this->mCascadeRestriction |= $row->pr_cascade;
2688                                 } else {
2689                                         // Trigger a lazy purge of expired restrictions
2690                                         $purgeExpired = true;
2691                                 }
2692                         }
2693
2694                         if ( $purgeExpired ) {
2695                                 Title::purgeExpiredRestrictions();
2696                         }
2697                 }
2698
2699                 $this->mRestrictionsLoaded = true;
2700         }
2701
2702         /**
2703          * Load restrictions from the page_restrictions table
2704          *
2705          * @param $oldFashionedRestrictions String comma-separated list of page
2706          *        restrictions from page table (pre 1.10)
2707          */
2708         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2709                 global $wgContLang;
2710                 if ( !$this->mRestrictionsLoaded ) {
2711                         if ( $this->exists() ) {
2712                                 $dbr = wfGetDB( DB_SLAVE );
2713
2714                                 $res = $dbr->select(
2715                                         'page_restrictions',
2716                                         '*',
2717                                         array( 'pr_page' => $this->getArticleID() ),
2718                                         __METHOD__
2719                                 );
2720
2721                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2722                         } else {
2723                                 $title_protection = $this->getTitleProtection();
2724
2725                                 if ( $title_protection ) {
2726                                         $now = wfTimestampNow();
2727                                         $expiry = $wgContLang->formatExpiry( $title_protection['pt_expiry'], TS_MW );
2728
2729                                         if ( !$expiry || $expiry > $now ) {
2730                                                 // Apply the restrictions
2731                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2732                                                 $this->mRestrictions['create'] = explode( ',', trim( $title_protection['pt_create_perm'] ) );
2733                                         } else { // Get rid of the old restrictions
2734                                                 Title::purgeExpiredRestrictions();
2735                                                 $this->mTitleProtection = false;
2736                                         }
2737                                 } else {
2738                                         $this->mRestrictionsExpiry['create'] = $wgContLang->formatExpiry( '', TS_MW );
2739                                 }
2740                                 $this->mRestrictionsLoaded = true;
2741                         }
2742                 }
2743         }
2744
2745         /**
2746          * Flush the protection cache in this object and force reload from the database.
2747          * This is used when updating protection from WikiPage::doUpdateRestrictions().
2748          */
2749         public function flushRestrictions() {
2750                 $this->mRestrictionsLoaded = false;
2751                 $this->mTitleProtection = null;
2752         }
2753
2754         /**
2755          * Purge expired restrictions from the page_restrictions table
2756          */
2757         static function purgeExpiredRestrictions() {
2758                 $dbw = wfGetDB( DB_MASTER );
2759                 $dbw->delete(
2760                         'page_restrictions',
2761                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2762                         __METHOD__
2763                 );
2764
2765                 $dbw->delete(
2766                         'protected_titles',
2767                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2768                         __METHOD__
2769                 );
2770         }
2771
2772         /**
2773          * Does this have subpages?  (Warning, usually requires an extra DB query.)
2774          *
2775          * @return Bool
2776          */
2777         public function hasSubpages() {
2778                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
2779                         # Duh
2780                         return false;
2781                 }
2782
2783                 # We dynamically add a member variable for the purpose of this method
2784                 # alone to cache the result.  There's no point in having it hanging
2785                 # around uninitialized in every Title object; therefore we only add it
2786                 # if needed and don't declare it statically.
2787                 if ( isset( $this->mHasSubpages ) ) {
2788                         return $this->mHasSubpages;
2789                 }
2790
2791                 $subpages = $this->getSubpages( 1 );
2792                 if ( $subpages instanceof TitleArray ) {
2793                         return $this->mHasSubpages = (bool)$subpages->count();
2794                 }
2795                 return $this->mHasSubpages = false;
2796         }
2797
2798         /**
2799          * Get all subpages of this page.
2800          *
2801          * @param $limit Int maximum number of subpages to fetch; -1 for no limit
2802          * @return mixed TitleArray, or empty array if this page's namespace
2803          *  doesn't allow subpages
2804          */
2805         public function getSubpages( $limit = -1 ) {
2806                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
2807                         return array();
2808                 }
2809
2810                 $dbr = wfGetDB( DB_SLAVE );
2811                 $conds['page_namespace'] = $this->getNamespace();
2812                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
2813                 $options = array();
2814                 if ( $limit > -1 ) {
2815                         $options['LIMIT'] = $limit;
2816                 }
2817                 return $this->mSubpages = TitleArray::newFromResult(
2818                         $dbr->select( 'page',
2819                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
2820                                 $conds,
2821                                 __METHOD__,
2822                                 $options
2823                         )
2824                 );
2825         }
2826
2827         /**
2828          * Is there a version of this page in the deletion archive?
2829          *
2830          * @return Int the number of archived revisions
2831          */
2832         public function isDeleted() {
2833                 if ( $this->getNamespace() < 0 ) {
2834                         $n = 0;
2835                 } else {
2836                         $dbr = wfGetDB( DB_SLAVE );
2837
2838                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2839                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2840                                 __METHOD__
2841                         );
2842                         if ( $this->getNamespace() == NS_FILE ) {
2843                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2844                                         array( 'fa_name' => $this->getDBkey() ),
2845                                         __METHOD__
2846                                 );
2847                         }
2848                 }
2849                 return (int)$n;
2850         }
2851
2852         /**
2853          * Is there a version of this page in the deletion archive?
2854          *
2855          * @return Boolean
2856          */
2857         public function isDeletedQuick() {
2858                 if ( $this->getNamespace() < 0 ) {
2859                         return false;
2860                 }
2861                 $dbr = wfGetDB( DB_SLAVE );
2862                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2863                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2864                         __METHOD__
2865                 );
2866                 if ( !$deleted && $this->getNamespace() == NS_FILE ) {
2867                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2868                                 array( 'fa_name' => $this->getDBkey() ),
2869                                 __METHOD__
2870                         );
2871                 }
2872                 return $deleted;
2873         }
2874
2875         /**
2876          * Get the article ID for this Title from the link cache,
2877          * adding it if necessary
2878          *
2879          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select
2880          *  for update
2881          * @return Int the ID
2882          */
2883         public function getArticleID( $flags = 0 ) {
2884                 if ( $this->getNamespace() < 0 ) {
2885                         return $this->mArticleID = 0;
2886                 }
2887                 $linkCache = LinkCache::singleton();
2888                 if ( $flags & self::GAID_FOR_UPDATE ) {
2889                         $oldUpdate = $linkCache->forUpdate( true );
2890                         $linkCache->clearLink( $this );
2891                         $this->mArticleID = $linkCache->addLinkObj( $this );
2892                         $linkCache->forUpdate( $oldUpdate );
2893                 } else {
2894                         if ( -1 == $this->mArticleID ) {
2895                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2896                         }
2897                 }
2898                 return $this->mArticleID;
2899         }
2900
2901         /**
2902          * Is this an article that is a redirect page?
2903          * Uses link cache, adding it if necessary
2904          *
2905          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2906          * @return Bool
2907          */
2908         public function isRedirect( $flags = 0 ) {
2909                 if ( !is_null( $this->mRedirect ) ) {
2910                         return $this->mRedirect;
2911                 }
2912                 # Calling getArticleID() loads the field from cache as needed
2913                 if ( !$this->getArticleID( $flags ) ) {
2914                         return $this->mRedirect = false;
2915                 }
2916
2917                 $linkCache = LinkCache::singleton();
2918                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2919                 if ( $cached === null ) { # check the assumption that the cache actually knows about this title
2920                         # XXX: this does apparently happen, see https://bugzilla.wikimedia.org/show_bug.cgi?id=37209
2921                         #      as a stop gap, perhaps log this, but don't throw an exception?
2922                         throw new MWException( "LinkCache doesn't currently know about this title: " . $this->getPrefixedDBkey() );
2923                 }
2924
2925                 $this->mRedirect = (bool)$cached;
2926
2927                 return $this->mRedirect;
2928         }
2929
2930         /**
2931          * What is the length of this page?
2932          * Uses link cache, adding it if necessary
2933          *
2934          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2935          * @return Int
2936          */
2937         public function getLength( $flags = 0 ) {
2938                 if ( $this->mLength != -1 ) {
2939                         return $this->mLength;
2940                 }
2941                 # Calling getArticleID() loads the field from cache as needed
2942                 if ( !$this->getArticleID( $flags ) ) {
2943                         return $this->mLength = 0;
2944                 }
2945                 $linkCache = LinkCache::singleton();
2946                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'length' );
2947                 if ( $cached === null ) { # check the assumption that the cache actually knows about this title
2948                         # XXX: this does apparently happen, see https://bugzilla.wikimedia.org/show_bug.cgi?id=37209
2949                         #      as a stop gap, perhaps log this, but don't throw an exception?
2950                         throw new MWException( "LinkCache doesn't currently know about this title: " . $this->getPrefixedDBkey() );
2951                 }
2952
2953                 $this->mLength = intval( $cached );
2954
2955                 return $this->mLength;
2956         }
2957
2958         /**
2959          * What is the page_latest field for this page?
2960          *
2961          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2962          * @return Int or 0 if the page doesn't exist
2963          */
2964         public function getLatestRevID( $flags = 0 ) {
2965                 if ( !( $flags & Title::GAID_FOR_UPDATE ) && $this->mLatestID !== false ) {
2966                         return intval( $this->mLatestID );
2967                 }
2968                 # Calling getArticleID() loads the field from cache as needed
2969                 if ( !$this->getArticleID( $flags ) ) {
2970                         return $this->mLatestID = 0;
2971                 }
2972                 $linkCache = LinkCache::singleton();
2973                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'revision' );
2974                 if ( $cached === null ) { # check the assumption that the cache actually knows about this title
2975                         # XXX: this does apparently happen, see https://bugzilla.wikimedia.org/show_bug.cgi?id=37209
2976                         #      as a stop gap, perhaps log this, but don't throw an exception?
2977                         throw new MWException( "LinkCache doesn't currently know about this title: " . $this->getPrefixedDBkey() );
2978                 }
2979
2980                 $this->mLatestID = intval( $cached );
2981
2982                 return $this->mLatestID;
2983         }
2984
2985         /**
2986          * This clears some fields in this object, and clears any associated
2987          * keys in the "bad links" section of the link cache.
2988          *
2989          * - This is called from WikiPage::doEdit() and WikiPage::insertOn() to allow
2990          * loading of the new page_id. It's also called from
2991          * WikiPage::doDeleteArticleReal()
2992          *
2993          * @param $newid Int the new Article ID
2994          */
2995         public function resetArticleID( $newid ) {
2996                 $linkCache = LinkCache::singleton();
2997                 $linkCache->clearLink( $this );
2998
2999                 if ( $newid === false ) {
3000                         $this->mArticleID = -1;
3001                 } else {
3002                         $this->mArticleID = intval( $newid );
3003                 }
3004                 $this->mRestrictionsLoaded = false;
3005                 $this->mRestrictions = array();
3006                 $this->mRedirect = null;
3007                 $this->mLength = -1;
3008                 $this->mLatestID = false;
3009                 $this->mContentModel = false;
3010                 $this->mEstimateRevisions = null;
3011         }
3012
3013         /**
3014          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
3015          *
3016          * @param $text String containing title to capitalize
3017          * @param $ns int namespace index, defaults to NS_MAIN
3018          * @return String containing capitalized title
3019          */
3020         public static function capitalize( $text, $ns = NS_MAIN ) {
3021                 global $wgContLang;
3022
3023                 if ( MWNamespace::isCapitalized( $ns ) ) {
3024                         return $wgContLang->ucfirst( $text );
3025                 } else {
3026                         return $text;
3027                 }
3028         }
3029
3030         /**
3031          * Secure and split - main initialisation function for this object
3032          *
3033          * Assumes that mDbkeyform has been set, and is urldecoded
3034          * and uses underscores, but not otherwise munged.  This function
3035          * removes illegal characters, splits off the interwiki and
3036          * namespace prefixes, sets the other forms, and canonicalizes
3037          * everything.
3038          *
3039          * @return Bool true on success
3040          */
3041         private function secureAndSplit() {
3042                 global $wgContLang, $wgLocalInterwiki;
3043
3044                 # Initialisation
3045                 $this->mInterwiki = $this->mFragment = '';
3046                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
3047
3048                 $dbkey = $this->mDbkeyform;
3049
3050                 # Strip Unicode bidi override characters.
3051                 # Sometimes they slip into cut-n-pasted page titles, where the
3052                 # override chars get included in list displays.
3053                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
3054
3055                 # Clean up whitespace
3056                 # Note: use of the /u option on preg_replace here will cause
3057                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
3058                 # conveniently disabling them.
3059                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
3060                 $dbkey = trim( $dbkey, '_' );
3061
3062                 if ( $dbkey == '' ) {
3063                         return false;
3064                 }
3065
3066                 if ( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
3067                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
3068                         return false;
3069                 }
3070
3071                 $this->mDbkeyform = $dbkey;
3072
3073                 # Initial colon indicates main namespace rather than specified default
3074                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
3075                 if ( ':' == $dbkey[0] ) {
3076                         $this->mNamespace = NS_MAIN;
3077                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
3078                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
3079                 }
3080
3081                 # Namespace or interwiki prefix
3082                 $firstPass = true;
3083                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
3084                 do {
3085                         $m = array();
3086                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
3087                                 $p = $m[1];
3088                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
3089                                         # Ordinary namespace
3090                                         $dbkey = $m[2];
3091                                         $this->mNamespace = $ns;
3092                                         # For Talk:X pages, check if X has a "namespace" prefix
3093                                         if ( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
3094                                                 if ( $wgContLang->getNsIndex( $x[1] ) ) {
3095                                                         # Disallow Talk:File:x type titles...
3096                                                         return false;
3097                                                 } elseif ( Interwiki::isValidInterwiki( $x[1] ) ) {
3098                                                         # Disallow Talk:Interwiki:x type titles...
3099                                                         return false;
3100                                                 }
3101                                         }
3102                                 } elseif ( Interwiki::isValidInterwiki( $p ) ) {
3103                                         if ( !$firstPass ) {
3104                                                 # Can't make a local interwiki link to an interwiki link.
3105                                                 # That's just crazy!
3106                                                 return false;
3107                                         }
3108
3109                                         # Interwiki link
3110                                         $dbkey = $m[2];
3111                                         $this->mInterwiki = $wgContLang->lc( $p );
3112
3113                                         # Redundant interwiki prefix to the local wiki
3114                                         if ( $wgLocalInterwiki !== false
3115                                                 && 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) )
3116                                         {
3117                                                 if ( $dbkey == '' ) {
3118                                                         # Can't have an empty self-link
3119                                                         return false;
3120                                                 }
3121                                                 $this->mInterwiki = '';
3122                                                 $firstPass = false;
3123                                                 # Do another namespace split...
3124                                                 continue;
3125                                         }
3126
3127                                         # If there's an initial colon after the interwiki, that also
3128                                         # resets the default namespace
3129                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
3130                                                 $this->mNamespace = NS_MAIN;
3131                                                 $dbkey = substr( $dbkey, 1 );
3132                                         }
3133                                 }
3134                                 # If there's no recognized interwiki or namespace,
3135                                 # then let the colon expression be part of the title.
3136                         }
3137                         break;
3138                 } while ( true );
3139
3140                 # We already know that some pages won't be in the database!
3141                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
3142                         $this->mArticleID = 0;
3143                 }
3144                 $fragment = strstr( $dbkey, '#' );
3145                 if ( false !== $fragment ) {
3146                         $this->setFragment( $fragment );
3147                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
3148                         # remove whitespace again: prevents "Foo_bar_#"
3149                         # becoming "Foo_bar_"
3150                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
3151                 }
3152
3153                 # Reject illegal characters.
3154                 $rxTc = self::getTitleInvalidRegex();
3155                 if ( preg_match( $rxTc, $dbkey ) ) {
3156                         return false;
3157                 }
3158
3159                 # Pages with "/./" or "/../" appearing in the URLs will often be un-
3160                 # reachable due to the way web browsers deal with 'relative' URLs.
3161                 # Also, they conflict with subpage syntax.  Forbid them explicitly.
3162                 if ( strpos( $dbkey, '.' ) !== false &&
3163                          ( $dbkey === '.' || $dbkey === '..' ||
3164                            strpos( $dbkey, './' ) === 0  ||
3165                            strpos( $dbkey, '../' ) === 0 ||
3166                            strpos( $dbkey, '/./' ) !== false ||
3167                            strpos( $dbkey, '/../' ) !== false  ||
3168                            substr( $dbkey, -2 ) == '/.' ||
3169                            substr( $dbkey, -3 ) == '/..' ) )
3170                 {
3171                         return false;
3172                 }
3173
3174                 # Magic tilde sequences? Nu-uh!
3175                 if ( strpos( $dbkey, '~~~' ) !== false ) {
3176                         return false;
3177                 }
3178
3179                 # Limit the size of titles to 255 bytes. This is typically the size of the
3180                 # underlying database field. We make an exception for special pages, which
3181                 # don't need to be stored in the database, and may edge over 255 bytes due
3182                 # to subpage syntax for long titles, e.g. [[Special:Block/Long name]]
3183                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
3184                   strlen( $dbkey ) > 512 )
3185                 {
3186                         return false;
3187                 }
3188
3189                 # Normally, all wiki links are forced to have an initial capital letter so [[foo]]
3190                 # and [[Foo]] point to the same place.  Don't force it for interwikis, since the
3191                 # other site might be case-sensitive.
3192                 $this->mUserCaseDBKey = $dbkey;
3193                 if ( $this->mInterwiki == '' ) {
3194                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
3195                 }
3196
3197                 # Can't make a link to a namespace alone... "empty" local links can only be
3198                 # self-links with a fragment identifier.
3199                 if ( $dbkey == '' && $this->mInterwiki == '' && $this->mNamespace != NS_MAIN ) {
3200                         return false;
3201                 }
3202
3203                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
3204                 // IP names are not allowed for accounts, and can only be referring to
3205                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
3206                 // there are numerous ways to present the same IP. Having sp:contribs scan
3207                 // them all is silly and having some show the edits and others not is
3208                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
3209                 $dbkey = ( $this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK )
3210                         ? IP::sanitizeIP( $dbkey )
3211                         : $dbkey;
3212
3213                 // Any remaining initial :s are illegal.
3214                 if ( $dbkey !== '' && ':' == $dbkey[0] ) {
3215                         return false;
3216                 }
3217
3218                 # Fill fields
3219                 $this->mDbkeyform = $dbkey;
3220                 $this->mUrlform = wfUrlencode( $dbkey );
3221
3222                 $this->mTextform = str_replace( '_', ' ', $dbkey );
3223
3224                 return true;
3225         }
3226
3227         /**
3228          * Get an array of Title objects linking to this Title
3229          * Also stores the IDs in the link cache.
3230          *
3231          * WARNING: do not use this function on arbitrary user-supplied titles!
3232          * On heavily-used templates it will max out the memory.
3233          *
3234          * @param $options Array: may be FOR UPDATE
3235          * @param $table String: table name
3236          * @param $prefix String: fields prefix
3237          * @return Array of Title objects linking here
3238          */
3239         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3240                 if ( count( $options ) > 0 ) {
3241                         $db = wfGetDB( DB_MASTER );
3242                 } else {
3243                         $db = wfGetDB( DB_SLAVE );
3244                 }
3245
3246                 $res = $db->select(
3247                         array( 'page', $table ),
3248                         self::getSelectFields(),
3249                         array(
3250                                 "{$prefix}_from=page_id",
3251                                 "{$prefix}_namespace" => $this->getNamespace(),
3252                                 "{$prefix}_title"     => $this->getDBkey() ),
3253                         __METHOD__,
3254                         $options
3255                 );
3256
3257                 $retVal = array();
3258                 if ( $res->numRows() ) {
3259                         $linkCache = LinkCache::singleton();
3260                         foreach ( $res as $row ) {
3261                                 $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title );
3262                                 if ( $titleObj ) {
3263                                         $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3264                                         $retVal[] = $titleObj;
3265                                 }
3266                         }
3267                 }
3268                 return $retVal;
3269         }
3270
3271         /**
3272          * Get an array of Title objects using this Title as a template
3273          * Also stores the IDs in the link cache.
3274          *
3275          * WARNING: do not use this function on arbitrary user-supplied titles!
3276          * On heavily-used templates it will max out the memory.
3277          *
3278          * @param $options Array: may be FOR UPDATE
3279          * @return Array of Title the Title objects linking here
3280          */
3281         public function getTemplateLinksTo( $options = array() ) {
3282                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
3283         }
3284
3285         /**
3286          * Get an array of Title objects linked from this Title
3287          * Also stores the IDs in the link cache.
3288          *
3289          * WARNING: do not use this function on arbitrary user-supplied titles!
3290          * On heavily-used templates it will max out the memory.
3291          *
3292          * @param $options Array: may be FOR UPDATE
3293          * @param $table String: table name
3294          * @param $prefix String: fields prefix
3295          * @return Array of Title objects linking here
3296          */
3297         public function getLinksFrom( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3298                 global $wgContentHandlerUseDB;
3299
3300                 $id = $this->getArticleID();
3301
3302                 # If the page doesn't exist; there can't be any link from this page
3303                 if ( !$id ) {
3304                         return array();
3305                 }
3306
3307                 if ( count( $options ) > 0 ) {
3308                         $db = wfGetDB( DB_MASTER );
3309                 } else {
3310                         $db = wfGetDB( DB_SLAVE );
3311                 }
3312
3313                 $namespaceFiled = "{$prefix}_namespace";
3314                 $titleField = "{$prefix}_title";
3315
3316                 $fields = array( $namespaceFiled, $titleField, 'page_id', 'page_len', 'page_is_redirect', 'page_latest' );
3317                 if ( $wgContentHandlerUseDB ) $fields[] = 'page_content_model';
3318
3319                 $res = $db->select(
3320                         array( $table, 'page' ),
3321                         $fields,
3322                         array( "{$prefix}_from" => $id ),
3323                         __METHOD__,
3324                         $options,
3325                         array( 'page' => array( 'LEFT JOIN', array( "page_namespace=$namespaceFiled", "page_title=$titleField" ) ) )
3326                 );
3327
3328                 $retVal = array();
3329                 if ( $res->numRows() ) {
3330                         $linkCache = LinkCache::singleton();
3331                         foreach ( $res as $row ) {
3332                                 $titleObj = Title::makeTitle( $row->$namespaceFiled, $row->$titleField );
3333                                 if ( $titleObj ) {
3334                                         if ( $row->page_id ) {
3335                                                 $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3336                                         } else {
3337                                                 $linkCache->addBadLinkObj( $titleObj );
3338                                         }
3339                                         $retVal[] = $titleObj;
3340                                 }
3341                         }
3342                 }
3343                 return $retVal;
3344         }
3345
3346         /**
3347          * Get an array of Title objects used on this Title as a template
3348          * Also stores the IDs in the link cache.
3349          *
3350          * WARNING: do not use this function on arbitrary user-supplied titles!
3351          * On heavily-used templates it will max out the memory.
3352          *
3353          * @param $options Array: may be FOR UPDATE
3354          * @return Array of Title the Title objects used here
3355          */
3356         public function getTemplateLinksFrom( $options = array() ) {
3357                 return $this->getLinksFrom( $options, 'templatelinks', 'tl' );
3358         }
3359
3360         /**
3361          * Get an array of Title objects referring to non-existent articles linked from this page
3362          *
3363          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
3364          * @return Array of Title the Title objects
3365          */
3366         public function getBrokenLinksFrom() {
3367                 if ( $this->getArticleID() == 0 ) {
3368                         # All links from article ID 0 are false positives
3369                         return array();
3370                 }
3371
3372                 $dbr = wfGetDB( DB_SLAVE );
3373                 $res = $dbr->select(
3374                         array( 'page', 'pagelinks' ),
3375                         array( 'pl_namespace', 'pl_title' ),
3376                         array(
3377                                 'pl_from' => $this->getArticleID(),
3378                                 'page_namespace IS NULL'
3379                         ),
3380                         __METHOD__, array(),
3381                         array(
3382                                 'page' => array(
3383                                         'LEFT JOIN',
3384                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
3385                                 )
3386                         )
3387                 );
3388
3389                 $retVal = array();
3390                 foreach ( $res as $row ) {
3391                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
3392                 }
3393                 return $retVal;
3394         }
3395
3396
3397         /**
3398          * Get a list of URLs to purge from the Squid cache when this
3399          * page changes
3400          *
3401          * @return Array of String the URLs
3402          */
3403         public function getSquidURLs() {
3404                 $urls = array(
3405                         $this->getInternalURL(),
3406                         $this->getInternalURL( 'action=history' )
3407                 );
3408
3409                 $pageLang = $this->getPageLanguage();
3410                 if ( $pageLang->hasVariants() ) {
3411                         $variants = $pageLang->getVariants();
3412                         foreach ( $variants as $vCode ) {
3413                                 $urls[] = $this->getInternalURL( '', $vCode );
3414                         }
3415                 }
3416
3417                 return $urls;
3418         }
3419
3420         /**
3421          * Purge all applicable Squid URLs
3422          */
3423         public function purgeSquid() {
3424                 global $wgUseSquid;
3425                 if ( $wgUseSquid ) {
3426                         $urls = $this->getSquidURLs();
3427                         $u = new SquidUpdate( $urls );
3428                         $u->doUpdate();
3429                 }
3430         }
3431
3432         /**
3433          * Move this page without authentication
3434          *
3435          * @param $nt Title the new page Title
3436          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3437          */
3438         public function moveNoAuth( &$nt ) {
3439                 return $this->moveTo( $nt, false );
3440         }
3441
3442         /**
3443          * Check whether a given move operation would be valid.
3444          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
3445          *
3446          * @param $nt Title the new title
3447          * @param $auth Bool indicates whether $wgUser's permissions
3448          *  should be checked
3449          * @param $reason String is the log summary of the move, used for spam checking
3450          * @return Mixed True on success, getUserPermissionsErrors()-like array on failure
3451          */
3452         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
3453                 global $wgUser, $wgContentHandlerUseDB;
3454
3455                 $errors = array();
3456                 if ( !$nt ) {
3457                         // Normally we'd add this to $errors, but we'll get
3458                         // lots of syntax errors if $nt is not an object
3459                         return array( array( 'badtitletext' ) );
3460                 }
3461                 if ( $this->equals( $nt ) ) {
3462                         $errors[] = array( 'selfmove' );
3463                 }
3464                 if ( !$this->isMovable() ) {
3465                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
3466                 }
3467                 if ( $nt->getInterwiki() != '' ) {
3468                         $errors[] = array( 'immobile-target-namespace-iw' );
3469                 }
3470                 if ( !$nt->isMovable() ) {
3471                         $errors[] = array( 'immobile-target-namespace', $nt->getNsText() );
3472                 }
3473
3474                 $oldid = $this->getArticleID();
3475                 $newid = $nt->getArticleID();
3476
3477                 if ( strlen( $nt->getDBkey() ) < 1 ) {
3478                         $errors[] = array( 'articleexists' );
3479                 }
3480                 if ( ( $this->getDBkey() == '' ) ||
3481                          ( !$oldid ) ||
3482                          ( $nt->getDBkey() == '' ) ) {
3483                         $errors[] = array( 'badarticleerror' );
3484                 }
3485
3486                 // Content model checks
3487                 if ( !$wgContentHandlerUseDB &&
3488                                 $this->getContentModel() !== $nt->getContentModel() ) {
3489                         // can't move a page if that would change the page's content model
3490                         $errors[] = array( 'bad-target-model',
3491                                                         ContentHandler::getLocalizedName( $this->getContentModel() ),
3492                                                         ContentHandler::getLocalizedName( $nt->getContentModel() ) );
3493                 }
3494
3495                 // Image-specific checks
3496                 if ( $this->getNamespace() == NS_FILE ) {
3497                         $errors = array_merge( $errors, $this->validateFileMoveOperation( $nt ) );
3498                 }
3499
3500                 if ( $nt->getNamespace() == NS_FILE && $this->getNamespace() != NS_FILE ) {
3501                         $errors[] = array( 'nonfile-cannot-move-to-file' );
3502                 }
3503
3504                 if ( $auth ) {
3505                         $errors = wfMergeErrorArrays( $errors,
3506                                 $this->getUserPermissionsErrors( 'move', $wgUser ),
3507                                 $this->getUserPermissionsErrors( 'edit', $wgUser ),
3508                                 $nt->getUserPermissionsErrors( 'move-target', $wgUser ),
3509                                 $nt->getUserPermissionsErrors( 'edit', $wgUser ) );
3510                 }
3511
3512                 $match = EditPage::matchSummarySpamRegex( $reason );
3513                 if ( $match !== false ) {
3514                         // This is kind of lame, won't display nice
3515                         $errors[] = array( 'spamprotectiontext' );
3516                 }
3517
3518                 $err = null;
3519                 if ( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
3520                         $errors[] = array( 'hookaborted', $err );
3521                 }
3522
3523                 # The move is allowed only if (1) the target doesn't exist, or
3524                 # (2) the target is a redirect to the source, and has no history
3525                 # (so we can undo bad moves right after they're done).
3526
3527                 if ( 0 != $newid ) { # Target exists; check for validity
3528                         if ( !$this->isValidMoveTarget( $nt ) ) {
3529                                 $errors[] = array( 'articleexists' );
3530                         }
3531                 } else {
3532                         $tp = $nt->getTitleProtection();
3533                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
3534                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
3535                                 $errors[] = array( 'cantmove-titleprotected' );
3536                         }
3537                 }
3538                 if ( empty( $errors ) ) {
3539                         return true;
3540                 }
3541                 return $errors;
3542         }
3543
3544         /**
3545          * Check if the requested move target is a valid file move target
3546          * @param Title $nt Target title
3547          * @return array List of errors
3548          */
3549         protected function validateFileMoveOperation( $nt ) {
3550                 global $wgUser;
3551
3552                 $errors = array();
3553
3554                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is not allowed until below
3555
3556                 $file = wfLocalFile( $this );
3557                 if ( $file->exists() ) {
3558                         if ( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
3559                                 $errors[] = array( 'imageinvalidfilename' );
3560                         }
3561                         if ( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
3562                                 $errors[] = array( 'imagetypemismatch' );
3563                         }
3564                 }
3565
3566                 if ( $nt->getNamespace() != NS_FILE ) {
3567                         $errors[] = array( 'imagenocrossnamespace' );
3568                         // From here we want to do checks on a file object, so if we can't
3569                         // create one, we must return.
3570                         return $errors;
3571                 }
3572
3573                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is allowed below here
3574
3575                 $destFile = wfLocalFile( $nt );
3576                 if ( !$wgUser->isAllowed( 'reupload-shared' ) && !$destFile->exists() && wfFindFile( $nt ) ) {
3577                         $errors[] = array( 'file-exists-sharedrepo' );
3578                 }
3579
3580                 return $errors;
3581         }
3582
3583         /**
3584          * Move a title to a new location
3585          *
3586          * @param $nt Title the new title
3587          * @param $auth Bool indicates whether $wgUser's permissions
3588          *  should be checked
3589          * @param $reason String the reason for the move
3590          * @param $createRedirect Bool Whether to create a redirect from the old title to the new title.
3591          *  Ignored if the user doesn't have the suppressredirect right.
3592          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3593          */
3594         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
3595                 global $wgUser;
3596                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
3597                 if ( is_array( $err ) ) {
3598                         // Auto-block user's IP if the account was "hard" blocked
3599                         $wgUser->spreadAnyEditBlock();
3600                         return $err;
3601                 }
3602                 // Check suppressredirect permission
3603                 if ( $auth && !$wgUser->isAllowed( 'suppressredirect' ) ) {
3604                         $createRedirect = true;
3605                 }
3606
3607                 // If it is a file, move it first.
3608                 // It is done before all other moving stuff is done because it's hard to revert.
3609                 $dbw = wfGetDB( DB_MASTER );
3610                 if ( $this->getNamespace() == NS_FILE ) {
3611                         $file = wfLocalFile( $this );
3612                         if ( $file->exists() ) {
3613                                 $status = $file->move( $nt );
3614                                 if ( !$status->isOk() ) {
3615                                         return $status->getErrorsArray();
3616                                 }
3617                         }
3618                         // Clear RepoGroup process cache
3619                         RepoGroup::singleton()->clearCache( $this );
3620                         RepoGroup::singleton()->clearCache( $nt ); # clear false negative cache
3621                 }
3622
3623                 $dbw->begin( __METHOD__ ); # If $file was a LocalFile, its transaction would have closed our own.
3624                 $pageid = $this->getArticleID( self::GAID_FOR_UPDATE );
3625                 $protected = $this->isProtected();
3626
3627                 // Do the actual move
3628                 $this->moveToInternal( $nt, $reason, $createRedirect );
3629
3630                 // Refresh the sortkey for this row.  Be careful to avoid resetting
3631                 // cl_timestamp, which may disturb time-based lists on some sites.
3632                 $prefixes = $dbw->select(
3633                         'categorylinks',
3634                         array( 'cl_sortkey_prefix', 'cl_to' ),
3635                         array( 'cl_from' => $pageid ),
3636                         __METHOD__
3637                 );
3638                 foreach ( $prefixes as $prefixRow ) {
3639                         $prefix = $prefixRow->cl_sortkey_prefix;
3640                         $catTo = $prefixRow->cl_to;
3641                         $dbw->update( 'categorylinks',
3642                                 array(
3643                                         'cl_sortkey' => Collation::singleton()->getSortKey(
3644                                                 $nt->getCategorySortkey( $prefix ) ),
3645                                         'cl_timestamp=cl_timestamp' ),
3646                                 array(
3647                                         'cl_from' => $pageid,
3648                                         'cl_to' => $catTo ),
3649                                 __METHOD__
3650                         );
3651                 }
3652
3653                 $redirid = $this->getArticleID();
3654
3655                 if ( $protected ) {
3656                         # Protect the redirect title as the title used to be...
3657                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
3658                                 array(
3659                                         'pr_page'    => $redirid,
3660                                         'pr_type'    => 'pr_type',
3661                                         'pr_level'   => 'pr_level',
3662                                         'pr_cascade' => 'pr_cascade',
3663                                         'pr_user'    => 'pr_user',
3664                                         'pr_expiry'  => 'pr_expiry'
3665                                 ),
3666                                 array( 'pr_page' => $pageid ),
3667                                 __METHOD__,
3668                                 array( 'IGNORE' )
3669                         );
3670                         # Update the protection log
3671                         $log = new LogPage( 'protect' );
3672                         $comment = wfMessage(
3673                                 'prot_1movedto2',
3674                                 $this->getPrefixedText(),
3675                                 $nt->getPrefixedText()
3676                         )->inContentLanguage()->text();
3677                         if ( $reason ) {
3678                                 $comment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
3679                         }
3680                         // @todo FIXME: $params?
3681                         $log->addEntry( 'move_prot', $nt, $comment, array( $this->getPrefixedText() ) );
3682                 }
3683
3684                 # Update watchlists
3685                 $oldnamespace = $this->getNamespace() & ~1;
3686                 $newnamespace = $nt->getNamespace() & ~1;
3687                 $oldtitle = $this->getDBkey();
3688                 $newtitle = $nt->getDBkey();
3689
3690                 if ( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
3691                         WatchedItem::duplicateEntries( $this, $nt );
3692                 }
3693
3694                 $dbw->commit( __METHOD__ );
3695
3696                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3697                 return true;
3698         }
3699
3700         /**
3701          * Move page to a title which is either a redirect to the
3702          * source page or nonexistent
3703          *
3704          * @param $nt Title the page to move to, which should be a redirect or nonexistent
3705          * @param $reason String The reason for the move
3706          * @param $createRedirect Bool Whether to leave a redirect at the old title. Does not check
3707          *   if the user has the suppressredirect right
3708          * @throws MWException
3709          */
3710         private function moveToInternal( &$nt, $reason = '', $createRedirect = true ) {
3711                 global $wgUser, $wgContLang;
3712
3713                 if ( $nt->exists() ) {
3714                         $moveOverRedirect = true;
3715                         $logType = 'move_redir';
3716                 } else {
3717                         $moveOverRedirect = false;
3718                         $logType = 'move';
3719                 }
3720
3721                 if ( $createRedirect ) {
3722                         $contentHandler = ContentHandler::getForTitle( $this );
3723                         $redirectContent = $contentHandler->makeRedirectContent( $nt );
3724
3725                         // NOTE: If this page's content model does not support redirects, $redirectContent will be null.
3726                 } else {
3727                         $redirectContent = null;
3728                 }
3729
3730                 $logEntry = new ManualLogEntry( 'move', $logType );
3731                 $logEntry->setPerformer( $wgUser );
3732                 $logEntry->setTarget( $this );
3733                 $logEntry->setComment( $reason );
3734                 $logEntry->setParameters( array(
3735                         '4::target' => $nt->getPrefixedText(),
3736                         '5::noredir' => $redirectContent ? '0': '1',
3737                 ) );
3738
3739                 $formatter = LogFormatter::newFromEntry( $logEntry );
3740                 $formatter->setContext( RequestContext::newExtraneousContext( $this ) );
3741                 $comment = $formatter->getPlainActionText();
3742                 if ( $reason ) {
3743                         $comment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
3744                 }
3745                 # Truncate for whole multibyte characters.
3746                 $comment = $wgContLang->truncate( $comment, 255 );
3747
3748                 $oldid = $this->getArticleID();
3749
3750                 $dbw = wfGetDB( DB_MASTER );
3751
3752                 $newpage = WikiPage::factory( $nt );
3753
3754                 if ( $moveOverRedirect ) {
3755                         $newid = $nt->getArticleID();
3756
3757                         # Delete the old redirect. We don't save it to history since
3758                         # by definition if we've got here it's rather uninteresting.
3759                         # We have to remove it so that the next step doesn't trigger
3760                         # a conflict on the unique namespace+title index...
3761                         $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3762
3763                         $newpage->doDeleteUpdates( $newid );
3764                 }
3765
3766                 # Save a null revision in the page's history notifying of the move
3767                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3768                 if ( !is_object( $nullRevision ) ) {
3769                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3770                 }
3771
3772                 $nullRevision->insertOn( $dbw );
3773
3774                 # Change the name of the target page:
3775                 $dbw->update( 'page',
3776                         /* SET */ array(
3777                                 'page_namespace' => $nt->getNamespace(),
3778                                 'page_title'     => $nt->getDBkey(),
3779                         ),
3780                         /* WHERE */ array( 'page_id' => $oldid ),
3781                         __METHOD__
3782                 );
3783
3784                 $this->resetArticleID( 0 );
3785                 $nt->resetArticleID( $oldid );
3786
3787                 $newpage->updateRevisionOn( $dbw, $nullRevision );
3788
3789                 wfRunHooks( 'NewRevisionFromEditComplete',
3790                         array( $newpage, $nullRevision, $nullRevision->getParentId(), $wgUser ) );
3791
3792                 $newpage->doEditUpdates( $nullRevision, $wgUser, array( 'changed' => false ) );
3793
3794                 if ( !$moveOverRedirect ) {
3795                         WikiPage::onArticleCreate( $nt );
3796                 }
3797
3798                 # Recreate the redirect, this time in the other direction.
3799                 if ( !$redirectContent ) {
3800                         WikiPage::onArticleDelete( $this );
3801                 } else {
3802                         $redirectArticle = WikiPage::factory( $this );
3803                         $newid = $redirectArticle->insertOn( $dbw );
3804                         if ( $newid ) { // sanity
3805                                 $redirectRevision = new Revision( array(
3806                                         'page'    => $newid,
3807                                         'comment' => $comment,
3808                                         'content'    => $redirectContent ) );
3809                                 $redirectRevision->insertOn( $dbw );
3810                                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3811
3812                                 wfRunHooks( 'NewRevisionFromEditComplete',
3813                                         array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3814
3815                                 $redirectArticle->doEditUpdates( $redirectRevision, $wgUser, array( 'created' => true ) );
3816                         }
3817                 }
3818
3819                 # Log the move
3820                 $logid = $logEntry->insert();
3821                 $logEntry->publish( $logid );
3822         }
3823
3824         /**
3825          * Move this page's subpages to be subpages of $nt
3826          *
3827          * @param $nt Title Move target
3828          * @param $auth bool Whether $wgUser's permissions should be checked
3829          * @param $reason string The reason for the move
3830          * @param $createRedirect bool Whether to create redirects from the old subpages to
3831          *     the new ones Ignored if the user doesn't have the 'suppressredirect' right
3832          * @return mixed array with old page titles as keys, and strings (new page titles) or
3833          *     arrays (errors) as values, or an error array with numeric indices if no pages
3834          *     were moved
3835          */
3836         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3837                 global $wgMaximumMovedPages;
3838                 // Check permissions
3839                 if ( !$this->userCan( 'move-subpages' ) ) {
3840                         return array( 'cant-move-subpages' );
3841                 }
3842                 // Do the source and target namespaces support subpages?
3843                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
3844                         return array( 'namespace-nosubpages',
3845                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3846                 }
3847                 if ( !MWNamespace::hasSubpages( $nt->getNamespace() ) ) {
3848                         return array( 'namespace-nosubpages',
3849                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3850                 }
3851
3852                 $subpages = $this->getSubpages( $wgMaximumMovedPages + 1 );
3853                 $retval = array();
3854                 $count = 0;
3855                 foreach ( $subpages as $oldSubpage ) {
3856                         $count++;
3857                         if ( $count > $wgMaximumMovedPages ) {
3858                                 $retval[$oldSubpage->getPrefixedTitle()] =
3859                                                 array( 'movepage-max-pages',
3860                                                         $wgMaximumMovedPages );
3861                                 break;
3862                         }
3863
3864                         // We don't know whether this function was called before
3865                         // or after moving the root page, so check both
3866                         // $this and $nt
3867                         if ( $oldSubpage->getArticleID() == $this->getArticleID() ||
3868                                         $oldSubpage->getArticleID() == $nt->getArticleID() )
3869                         {
3870                                 // When moving a page to a subpage of itself,
3871                                 // don't move it twice
3872                                 continue;
3873                         }
3874                         $newPageName = preg_replace(
3875                                         '#^' . preg_quote( $this->getDBkey(), '#' ) . '#',
3876                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3877                                         $oldSubpage->getDBkey() );
3878                         if ( $oldSubpage->isTalkPage() ) {
3879                                 $newNs = $nt->getTalkPage()->getNamespace();
3880                         } else {
3881                                 $newNs = $nt->getSubjectPage()->getNamespace();
3882                         }
3883                         # Bug 14385: we need makeTitleSafe because the new page names may
3884                         # be longer than 255 characters.
3885                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3886
3887                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3888                         if ( $success === true ) {
3889                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3890                         } else {
3891                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3892                         }
3893                 }
3894                 return $retval;
3895         }
3896
3897         /**
3898          * Checks if this page is just a one-rev redirect.
3899          * Adds lock, so don't use just for light purposes.
3900          *
3901          * @return Bool
3902          */
3903         public function isSingleRevRedirect() {
3904                 global $wgContentHandlerUseDB;
3905
3906                 $dbw = wfGetDB( DB_MASTER );
3907
3908                 # Is it a redirect?
3909                 $fields = array( 'page_is_redirect', 'page_latest', 'page_id' );
3910                 if ( $wgContentHandlerUseDB ) $fields[] = 'page_content_model';
3911
3912                 $row = $dbw->selectRow( 'page',
3913                         $fields,
3914                         $this->pageCond(),
3915                         __METHOD__,
3916                         array( 'FOR UPDATE' )
3917                 );
3918                 # Cache some fields we may want
3919                 $this->mArticleID = $row ? intval( $row->page_id ) : 0;
3920                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3921                 $this->mLatestID = $row ? intval( $row->page_latest ) : false;
3922                 $this->mContentModel = $row && isset( $row->page_content_model ) ? strval( $row->page_content_model ) : false;
3923                 if ( !$this->mRedirect ) {
3924                         return false;
3925                 }
3926                 # Does the article have a history?
3927                 $row = $dbw->selectField( array( 'page', 'revision' ),
3928                         'rev_id',
3929                         array( 'page_namespace' => $this->getNamespace(),
3930                                 'page_title' => $this->getDBkey(),
3931                                 'page_id=rev_page',
3932                                 'page_latest != rev_id'
3933                         ),
3934                         __METHOD__,
3935                         array( 'FOR UPDATE' )
3936                 );
3937                 # Return true if there was no history
3938                 return ( $row === false );
3939         }
3940
3941         /**
3942          * Checks if $this can be moved to a given Title
3943          * - Selects for update, so don't call it unless you mean business
3944          *
3945          * @param $nt Title the new title to check
3946          * @return Bool
3947          */
3948         public function isValidMoveTarget( $nt ) {
3949                 # Is it an existing file?
3950                 if ( $nt->getNamespace() == NS_FILE ) {
3951                         $file = wfLocalFile( $nt );
3952                         if ( $file->exists() ) {
3953                                 wfDebug( __METHOD__ . ": file exists\n" );
3954                                 return false;
3955                         }
3956                 }
3957                 # Is it a redirect with no history?
3958                 if ( !$nt->isSingleRevRedirect() ) {
3959                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3960                         return false;
3961                 }
3962                 # Get the article text
3963                 $rev = Revision::newFromTitle( $nt, false, Revision::READ_LATEST );
3964                 if( !is_object( $rev ) ){
3965                         return false;
3966                 }
3967                 $content = $rev->getContent();
3968                 # Does the redirect point to the source?
3969                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3970                 $redirTitle = $content->getRedirectTarget();
3971
3972                 if ( $redirTitle ) {
3973                         if ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3974                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) {
3975                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3976                                 return false;
3977                         } else {
3978                                 return true;
3979                         }
3980                 } else {
3981                         # Fail safe (not a redirect after all. strange.)
3982                         wfDebug( __METHOD__ . ": failsafe: database sais " . $nt->getPrefixedDBkey() .
3983                                                 " is a redirect, but it doesn't contain a valid redirect.\n" );
3984                         return false;
3985                 }
3986         }
3987
3988         /**
3989          * Get categories to which this Title belongs and return an array of
3990          * categories' names.
3991          *
3992          * @return Array of parents in the form:
3993          *        $parent => $currentarticle
3994          */
3995         public function getParentCategories() {
3996                 global $wgContLang;
3997
3998                 $data = array();
3999
4000                 $titleKey = $this->getArticleID();
4001
4002                 if ( $titleKey === 0 ) {
4003                         return $data;
4004                 }
4005
4006                 $dbr = wfGetDB( DB_SLAVE );
4007
4008                 $res = $dbr->select( 'categorylinks', '*',
4009                         array(
4010                                 'cl_from' => $titleKey,
4011                         ),
4012                         __METHOD__,
4013                         array()
4014                 );
4015
4016                 if ( $dbr->numRows( $res ) > 0 ) {
4017                         foreach ( $res as $row ) {
4018                                 // $data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
4019                                 $data[$wgContLang->getNSText( NS_CATEGORY ) . ':' . $row->cl_to] = $this->getFullText();
4020                         }
4021                 }
4022                 return $data;
4023         }
4024
4025         /**
4026          * Get a tree of parent categories
4027          *
4028          * @param $children Array with the children in the keys, to check for circular refs
4029          * @return Array Tree of parent categories
4030          */
4031         public function getParentCategoryTree( $children = array() ) {
4032                 $stack = array();
4033                 $parents = $this->getParentCategories();
4034
4035                 if ( $parents ) {
4036                         foreach ( $parents as $parent => $current ) {
4037                                 if ( array_key_exists( $parent, $children ) ) {
4038                                         # Circular reference
4039                                         $stack[$parent] = array();
4040                                 } else {
4041                                         $nt = Title::newFromText( $parent );
4042                                         if ( $nt ) {
4043                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array( $parent => 1 ) );
4044                                         }
4045                                 }
4046                         }
4047                 }
4048
4049                 return $stack;
4050         }
4051
4052         /**
4053          * Get an associative array for selecting this title from
4054          * the "page" table
4055          *
4056          * @return Array suitable for the $where parameter of DB::select()
4057          */
4058         public function pageCond() {
4059                 if ( $this->mArticleID > 0 ) {
4060                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
4061                         return array( 'page_id' => $this->mArticleID );
4062                 } else {
4063                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
4064                 }
4065         }
4066
4067         /**
4068          * Get the revision ID of the previous revision
4069          *
4070          * @param $revId Int Revision ID. Get the revision that was before this one.
4071          * @param $flags Int Title::GAID_FOR_UPDATE
4072          * @return Int|Bool Old revision ID, or FALSE if none exists
4073          */
4074         public function getPreviousRevisionID( $revId, $flags = 0 ) {
4075                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4076                 $revId = $db->selectField( 'revision', 'rev_id',
4077                         array(
4078                                 'rev_page' => $this->getArticleID( $flags ),
4079                                 'rev_id < ' . intval( $revId )
4080                         ),
4081                         __METHOD__,
4082                         array( 'ORDER BY' => 'rev_id DESC' )
4083                 );
4084
4085                 if ( $revId === false ) {
4086                         return false;
4087                 } else {
4088                         return intval( $revId );
4089                 }
4090         }
4091
4092         /**
4093          * Get the revision ID of the next revision
4094          *
4095          * @param $revId Int Revision ID. Get the revision that was after this one.
4096          * @param $flags Int Title::GAID_FOR_UPDATE
4097          * @return Int|Bool Next revision ID, or FALSE if none exists
4098          */
4099         public function getNextRevisionID( $revId, $flags = 0 ) {
4100                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4101                 $revId = $db->selectField( 'revision', 'rev_id',
4102                         array(
4103                                 'rev_page' => $this->getArticleID( $flags ),
4104                                 'rev_id > ' . intval( $revId )
4105                         ),
4106                         __METHOD__,
4107                         array( 'ORDER BY' => 'rev_id' )
4108                 );
4109
4110                 if ( $revId === false ) {
4111                         return false;
4112                 } else {
4113                         return intval( $revId );
4114                 }
4115         }
4116
4117         /**
4118          * Get the first revision of the page
4119          *
4120          * @param $flags Int Title::GAID_FOR_UPDATE
4121          * @return Revision|Null if page doesn't exist
4122          */
4123         public function getFirstRevision( $flags = 0 ) {
4124                 $pageId = $this->getArticleID( $flags );
4125                 if ( $pageId ) {
4126                         $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4127                         $row = $db->selectRow( 'revision', Revision::selectFields(),
4128                                 array( 'rev_page' => $pageId ),
4129                                 __METHOD__,
4130                                 array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
4131                         );
4132                         if ( $row ) {
4133                                 return new Revision( $row );
4134                         }
4135                 }
4136                 return null;
4137         }
4138
4139         /**
4140          * Get the oldest revision timestamp of this page
4141          *
4142          * @param $flags Int Title::GAID_FOR_UPDATE
4143          * @return String: MW timestamp
4144          */
4145         public function getEarliestRevTime( $flags = 0 ) {
4146                 $rev = $this->getFirstRevision( $flags );
4147                 return $rev ? $rev->getTimestamp() : null;
4148         }
4149
4150         /**
4151          * Check if this is a new page
4152          *
4153          * @return bool
4154          */
4155         public function isNewPage() {
4156                 $dbr = wfGetDB( DB_SLAVE );
4157                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
4158         }
4159
4160         /**
4161          * Check whether the number of revisions of this page surpasses $wgDeleteRevisionsLimit
4162          *
4163          * @return bool
4164          */
4165         public function isBigDeletion() {
4166                 global $wgDeleteRevisionsLimit;
4167
4168                 if ( !$wgDeleteRevisionsLimit ) {
4169                         return false;
4170                 }
4171
4172                 $revCount = $this->estimateRevisionCount();
4173                 return $revCount > $wgDeleteRevisionsLimit;
4174         }
4175
4176         /**
4177          * Get the  approximate revision count of this page.
4178          *
4179          * @return int
4180          */
4181         public function estimateRevisionCount() {
4182                 if ( !$this->exists() ) {
4183                         return 0;
4184                 }
4185
4186                 if ( $this->mEstimateRevisions === null ) {
4187                         $dbr = wfGetDB( DB_SLAVE );
4188                         $this->mEstimateRevisions = $dbr->estimateRowCount( 'revision', '*',
4189                                 array( 'rev_page' => $this->getArticleID() ), __METHOD__ );
4190                 }
4191
4192                 return $this->mEstimateRevisions;
4193         }
4194
4195         /**
4196          * Get the number of revisions between the given revision.
4197          * Used for diffs and other things that really need it.
4198          *
4199          * @param $old int|Revision Old revision or rev ID (first before range)
4200          * @param $new int|Revision New revision or rev ID (first after range)
4201          * @return Int Number of revisions between these revisions.
4202          */
4203         public function countRevisionsBetween( $old, $new ) {
4204                 if ( !( $old instanceof Revision ) ) {
4205                         $old = Revision::newFromTitle( $this, (int)$old );
4206                 }
4207                 if ( !( $new instanceof Revision ) ) {
4208                         $new = Revision::newFromTitle( $this, (int)$new );
4209                 }
4210                 if ( !$old || !$new ) {
4211                         return 0; // nothing to compare
4212                 }
4213                 $dbr = wfGetDB( DB_SLAVE );
4214                 return (int)$dbr->selectField( 'revision', 'count(*)',
4215                         array(
4216                                 'rev_page' => $this->getArticleID(),
4217                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4218                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4219                         ),
4220                         __METHOD__
4221                 );
4222         }
4223
4224         /**
4225          * Get the number of authors between the given revisions or revision IDs.
4226          * Used for diffs and other things that really need it.
4227          *
4228          * @param $old int|Revision Old revision or rev ID (first before range by default)
4229          * @param $new int|Revision New revision or rev ID (first after range by default)
4230          * @param $limit int Maximum number of authors
4231          * @param $options string|array (Optional): Single option, or an array of options:
4232          *     'include_old' Include $old in the range; $new is excluded.
4233          *     'include_new' Include $new in the range; $old is excluded.
4234          *     'include_both' Include both $old and $new in the range.
4235          *     Unknown option values are ignored.
4236          * @return int Number of revision authors in the range; zero if not both revisions exist
4237          */
4238         public function countAuthorsBetween( $old, $new, $limit, $options = array() ) {
4239                 if ( !( $old instanceof Revision ) ) {
4240                         $old = Revision::newFromTitle( $this, (int)$old );
4241                 }
4242                 if ( !( $new instanceof Revision ) ) {
4243                         $new = Revision::newFromTitle( $this, (int)$new );
4244                 }
4245                 // XXX: what if Revision objects are passed in, but they don't refer to this title?
4246                 // Add $old->getPage() != $new->getPage() || $old->getPage() != $this->getArticleID()
4247                 // in the sanity check below?
4248                 if ( !$old || !$new ) {
4249                         return 0; // nothing to compare
4250                 }
4251                 $old_cmp = '>';
4252                 $new_cmp = '<';
4253                 $options = (array) $options;
4254                 if ( in_array( 'include_old', $options ) ) {
4255                         $old_cmp = '>=';
4256                 }
4257                 if ( in_array( 'include_new', $options ) ) {
4258                         $new_cmp = '<=';
4259                 }
4260                 if ( in_array( 'include_both', $options ) ) {
4261                         $old_cmp = '>=';
4262                         $new_cmp = '<=';
4263                 }
4264                 // No DB query needed if $old and $new are the same or successive revisions:
4265                 if ( $old->getId() === $new->getId() ) {
4266                         return ( $old_cmp === '>' && $new_cmp === '<' ) ? 0 : 1;
4267                 } else if ( $old->getId() === $new->getParentId() ) {
4268                         if ( $old_cmp === '>' || $new_cmp === '<' ) {
4269                                 return ( $old_cmp === '>' && $new_cmp === '<' ) ? 0 : 1;
4270                         }
4271                         return ( $old->getRawUserText() === $new->getRawUserText() ) ? 1 : 2;
4272                 }
4273                 $dbr = wfGetDB( DB_SLAVE );
4274                 $res = $dbr->select( 'revision', 'DISTINCT rev_user_text',
4275                         array(
4276                                 'rev_page' => $this->getArticleID(),
4277                                 "rev_timestamp $old_cmp " . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4278                                 "rev_timestamp $new_cmp " . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4279                         ), __METHOD__,
4280                         array( 'LIMIT' => $limit + 1 ) // add one so caller knows it was truncated
4281                 );
4282                 return (int)$dbr->numRows( $res );
4283         }
4284
4285         /**
4286          * Compare with another title.
4287          *
4288          * @param $title Title
4289          * @return Bool
4290          */
4291         public function equals( Title $title ) {
4292                 // Note: === is necessary for proper matching of number-like titles.
4293                 return $this->getInterwiki() === $title->getInterwiki()
4294                         && $this->getNamespace() == $title->getNamespace()
4295                         && $this->getDBkey() === $title->getDBkey();
4296         }
4297
4298         /**
4299          * Check if this title is a subpage of another title
4300          *
4301          * @param $title Title
4302          * @return Bool
4303          */
4304         public function isSubpageOf( Title $title ) {
4305                 return $this->getInterwiki() === $title->getInterwiki()
4306                         && $this->getNamespace() == $title->getNamespace()
4307                         && strpos( $this->getDBkey(), $title->getDBkey() . '/' ) === 0;
4308         }
4309
4310         /**
4311          * Check if page exists.  For historical reasons, this function simply
4312          * checks for the existence of the title in the page table, and will
4313          * thus return false for interwiki links, special pages and the like.
4314          * If you want to know if a title can be meaningfully viewed, you should
4315          * probably call the isKnown() method instead.
4316          *
4317          * @return Bool
4318          */
4319         public function exists() {
4320                 return $this->getArticleID() != 0;
4321         }
4322
4323         /**
4324          * Should links to this title be shown as potentially viewable (i.e. as
4325          * "bluelinks"), even if there's no record by this title in the page
4326          * table?
4327          *
4328          * This function is semi-deprecated for public use, as well as somewhat
4329          * misleadingly named.  You probably just want to call isKnown(), which
4330          * calls this function internally.
4331          *
4332          * (ISSUE: Most of these checks are cheap, but the file existence check
4333          * can potentially be quite expensive.  Including it here fixes a lot of
4334          * existing code, but we might want to add an optional parameter to skip
4335          * it and any other expensive checks.)
4336          *
4337          * @return Bool
4338          */
4339         public function isAlwaysKnown() {
4340                 $isKnown = null;
4341
4342                 /**
4343                  * Allows overriding default behaviour for determining if a page exists.
4344                  * If $isKnown is kept as null, regular checks happen. If it's
4345                  * a boolean, this value is returned by the isKnown method.
4346                  *
4347                  * @since 1.20
4348                  *
4349                  * @param Title $title
4350                  * @param boolean|null $isKnown
4351                  */
4352                 wfRunHooks( 'TitleIsAlwaysKnown', array( $this, &$isKnown ) );
4353
4354                 if ( !is_null( $isKnown ) ) {
4355                         return $isKnown;
4356                 }
4357
4358                 if ( $this->mInterwiki != '' ) {
4359                         return true;  // any interwiki link might be viewable, for all we know
4360                 }
4361
4362                 switch( $this->mNamespace ) {
4363                         case NS_MEDIA:
4364                         case NS_FILE:
4365                                 // file exists, possibly in a foreign repo
4366                                 return (bool)wfFindFile( $this );
4367                         case NS_SPECIAL:
4368                                 // valid special page
4369                                 return SpecialPageFactory::exists( $this->getDBkey() );
4370                         case NS_MAIN:
4371                                 // selflink, possibly with fragment
4372                                 return $this->mDbkeyform == '';
4373                         case NS_MEDIAWIKI:
4374                                 // known system message
4375                                 return $this->hasSourceText() !== false;
4376                         default:
4377                                 return false;
4378                 }
4379         }
4380
4381         /**
4382          * Does this title refer to a page that can (or might) be meaningfully
4383          * viewed?  In particular, this function may be used to determine if
4384          * links to the title should be rendered as "bluelinks" (as opposed to
4385          * "redlinks" to non-existent pages).
4386          * Adding something else to this function will cause inconsistency
4387          * since LinkHolderArray calls isAlwaysKnown() and does its own
4388          * page existence check.
4389          *
4390          * @return Bool
4391          */
4392         public function isKnown() {
4393                 return $this->isAlwaysKnown() || $this->exists();
4394         }
4395
4396         /**
4397          * Does this page have source text?
4398          *
4399          * @return Boolean
4400          */
4401         public function hasSourceText() {
4402                 if ( $this->exists() ) {
4403                         return true;
4404                 }
4405
4406                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
4407                         // If the page doesn't exist but is a known system message, default
4408                         // message content will be displayed, same for language subpages-
4409                         // Use always content language to avoid loading hundreds of languages
4410                         // to get the link color.
4411                         global $wgContLang;
4412                         list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4413                         $message = wfMessage( $name )->inLanguage( $wgContLang )->useDatabase( false );
4414                         return $message->exists();
4415                 }
4416
4417                 return false;
4418         }
4419
4420         /**
4421          * Get the default message text or false if the message doesn't exist
4422          *
4423          * @return String or false
4424          */
4425         public function getDefaultMessageText() {
4426                 global $wgContLang;
4427
4428                 if ( $this->getNamespace() != NS_MEDIAWIKI ) { // Just in case
4429                         return false;
4430                 }
4431
4432                 list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4433                 $message = wfMessage( $name )->inLanguage( $lang )->useDatabase( false );
4434
4435                 if ( $message->exists() ) {
4436                         return $message->plain();
4437                 } else {
4438                         return false;
4439                 }
4440         }
4441
4442         /**
4443          * Updates page_touched for this page; called from LinksUpdate.php
4444          *
4445          * @return Bool true if the update succeded
4446          */
4447         public function invalidateCache() {
4448                 if ( wfReadOnly() ) {
4449                         return false;
4450                 }
4451                 $dbw = wfGetDB( DB_MASTER );
4452                 $success = $dbw->update(
4453                         'page',
4454                         array( 'page_touched' => $dbw->timestamp() ),
4455                         $this->pageCond(),
4456                         __METHOD__
4457                 );
4458                 HTMLFileCache::clearFileCache( $this );
4459                 return $success;
4460         }
4461
4462         /**
4463          * Update page_touched timestamps and send squid purge messages for
4464          * pages linking to this title. May be sent to the job queue depending
4465          * on the number of links. Typically called on create and delete.
4466          */
4467         public function touchLinks() {
4468                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
4469                 $u->doUpdate();
4470
4471                 if ( $this->getNamespace() == NS_CATEGORY ) {
4472                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
4473                         $u->doUpdate();
4474                 }
4475         }
4476
4477         /**
4478          * Get the last touched timestamp
4479          *
4480          * @param $db DatabaseBase: optional db
4481          * @return String last-touched timestamp
4482          */
4483         public function getTouched( $db = null ) {
4484                 $db = isset( $db ) ? $db : wfGetDB( DB_SLAVE );
4485                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
4486                 return $touched;
4487         }
4488
4489         /**
4490          * Get the timestamp when this page was updated since the user last saw it.
4491          *
4492          * @param $user User
4493          * @return String|Null
4494          */
4495         public function getNotificationTimestamp( $user = null ) {
4496                 global $wgUser, $wgShowUpdatedMarker;
4497                 // Assume current user if none given
4498                 if ( !$user ) {
4499                         $user = $wgUser;
4500                 }
4501                 // Check cache first
4502                 $uid = $user->getId();
4503                 // avoid isset here, as it'll return false for null entries
4504                 if ( array_key_exists( $uid, $this->mNotificationTimestamp ) ) {
4505                         return $this->mNotificationTimestamp[$uid];
4506                 }
4507                 if ( !$uid || !$wgShowUpdatedMarker ) {
4508                         return $this->mNotificationTimestamp[$uid] = false;
4509                 }
4510                 // Don't cache too much!
4511                 if ( count( $this->mNotificationTimestamp ) >= self::CACHE_MAX ) {
4512                         $this->mNotificationTimestamp = array();
4513                 }
4514                 $dbr = wfGetDB( DB_SLAVE );
4515                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
4516                         'wl_notificationtimestamp',
4517                         array(
4518                                 'wl_user' => $user->getId(),
4519                                 'wl_namespace' => $this->getNamespace(),
4520                                 'wl_title' => $this->getDBkey(),
4521                         ),
4522                         __METHOD__
4523                 );
4524                 return $this->mNotificationTimestamp[$uid];
4525         }
4526
4527         /**
4528          * Generate strings used for xml 'id' names in monobook tabs
4529          *
4530          * @param $prepend string defaults to 'nstab-'
4531          * @return String XML 'id' name
4532          */
4533         public function getNamespaceKey( $prepend = 'nstab-' ) {
4534                 global $wgContLang;
4535                 // Gets the subject namespace if this title
4536                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
4537                 // Checks if cononical namespace name exists for namespace
4538                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
4539                         // Uses canonical namespace name
4540                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
4541                 } else {
4542                         // Uses text of namespace
4543                         $namespaceKey = $this->getSubjectNsText();
4544                 }
4545                 // Makes namespace key lowercase
4546                 $namespaceKey = $wgContLang->lc( $namespaceKey );
4547                 // Uses main
4548                 if ( $namespaceKey == '' ) {
4549                         $namespaceKey = 'main';
4550                 }
4551                 // Changes file to image for backwards compatibility
4552                 if ( $namespaceKey == 'file' ) {
4553                         $namespaceKey = 'image';
4554                 }
4555                 return $prepend . $namespaceKey;
4556         }
4557
4558         /**
4559          * Get all extant redirects to this Title
4560          *
4561          * @param $ns Int|Null Single namespace to consider; NULL to consider all namespaces
4562          * @return Array of Title redirects to this title
4563          */
4564         public function getRedirectsHere( $ns = null ) {
4565                 $redirs = array();
4566
4567                 $dbr = wfGetDB( DB_SLAVE );
4568                 $where = array(
4569                         'rd_namespace' => $this->getNamespace(),
4570                         'rd_title' => $this->getDBkey(),
4571                         'rd_from = page_id'
4572                 );
4573                 if ( $this->isExternal() ) {
4574                         $where['rd_interwiki'] = $this->getInterwiki();
4575                 } else {
4576                         $where[] = 'rd_interwiki = ' . $dbr->addQuotes( '' ) . ' OR rd_interwiki IS NULL';
4577                 }
4578                 if ( !is_null( $ns ) ) {
4579                         $where['page_namespace'] = $ns;
4580                 }
4581
4582                 $res = $dbr->select(
4583                         array( 'redirect', 'page' ),
4584                         array( 'page_namespace', 'page_title' ),
4585                         $where,
4586                         __METHOD__
4587                 );
4588
4589                 foreach ( $res as $row ) {
4590                         $redirs[] = self::newFromRow( $row );
4591                 }
4592                 return $redirs;
4593         }
4594
4595         /**
4596          * Check if this Title is a valid redirect target
4597          *
4598          * @return Bool
4599          */
4600         public function isValidRedirectTarget() {
4601                 global $wgInvalidRedirectTargets;
4602
4603                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
4604                 if ( $this->isSpecial( 'Userlogout' ) ) {
4605                         return false;
4606                 }
4607
4608                 foreach ( $wgInvalidRedirectTargets as $target ) {
4609                         if ( $this->isSpecial( $target ) ) {
4610                                 return false;
4611                         }
4612                 }
4613
4614                 return true;
4615         }
4616
4617         /**
4618          * Get a backlink cache object
4619          *
4620          * @return BacklinkCache
4621          */
4622         public function getBacklinkCache() {
4623                 return BacklinkCache::get( $this );
4624         }
4625
4626         /**
4627          * Whether the magic words __INDEX__ and __NOINDEX__ function for  this page.
4628          *
4629          * @return Boolean
4630          */
4631         public function canUseNoindex() {
4632                 global $wgContentNamespaces, $wgExemptFromUserRobotsControl;
4633
4634                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
4635                         ? $wgContentNamespaces
4636                         : $wgExemptFromUserRobotsControl;
4637
4638                 return !in_array( $this->mNamespace, $bannedNamespaces );
4639
4640         }
4641
4642         /**
4643          * Returns the raw sort key to be used for categories, with the specified
4644          * prefix.  This will be fed to Collation::getSortKey() to get a
4645          * binary sortkey that can be used for actual sorting.
4646          *
4647          * @param $prefix string The prefix to be used, specified using
4648          *   {{defaultsort:}} or like [[Category:Foo|prefix]].  Empty for no
4649          *   prefix.
4650          * @return string
4651          */
4652         public function getCategorySortkey( $prefix = '' ) {
4653                 $unprefixed = $this->getText();
4654
4655                 // Anything that uses this hook should only depend
4656                 // on the Title object passed in, and should probably
4657                 // tell the users to run updateCollations.php --force
4658                 // in order to re-sort existing category relations.
4659                 wfRunHooks( 'GetDefaultSortkey', array( $this, &$unprefixed ) );
4660                 if ( $prefix !== '' ) {
4661                         # Separate with a line feed, so the unprefixed part is only used as
4662                         # a tiebreaker when two pages have the exact same prefix.
4663                         # In UCA, tab is the only character that can sort above LF
4664                         # so we strip both of them from the original prefix.
4665                         $prefix = strtr( $prefix, "\n\t", '  ' );
4666                         return "$prefix\n$unprefixed";
4667                 }
4668                 return $unprefixed;
4669         }
4670
4671         /**
4672          * Get the language in which the content of this page is written in
4673          * wikitext. Defaults to $wgContLang, but in certain cases it can be
4674          * e.g. $wgLang (such as special pages, which are in the user language).
4675          *
4676          * @since 1.18
4677          * @return Language
4678          */
4679         public function getPageLanguage() {
4680                 global $wgLang;
4681                 if ( $this->isSpecialPage() ) {
4682                         // special pages are in the user language
4683                         return $wgLang;
4684                 }
4685
4686                 //TODO: use the LinkCache to cache this! Note that this may depend on user settings, so the cache should be only per-request.
4687                 //NOTE: ContentHandler::getPageLanguage() may need to load the content to determine the page language!
4688                 $contentHandler = ContentHandler::getForTitle( $this );
4689                 $pageLang = $contentHandler->getPageLanguage( $this );
4690
4691                 // Hook at the end because we don't want to override the above stuff
4692                 wfRunHooks( 'PageContentLanguage', array( $this, &$pageLang, $wgLang ) );
4693                 return wfGetLangObj( $pageLang );
4694         }
4695
4696         /**
4697          * Get the language in which the content of this page is written when
4698          * viewed by user. Defaults to $wgContLang, but in certain cases it can be
4699          * e.g. $wgLang (such as special pages, which are in the user language).
4700          *
4701          * @since 1.20
4702          * @return Language
4703          */
4704         public function getPageViewLanguage() {
4705                 global $wgLang;
4706
4707                 if ( $this->isSpecialPage() ) {
4708                         // If the user chooses a variant, the content is actually
4709                         // in a language whose code is the variant code.
4710                         $variant = $wgLang->getPreferredVariant();
4711                         if ( $wgLang->getCode() !== $variant ) {
4712                                 return Language::factory( $variant );
4713                         }
4714
4715                         return $wgLang;
4716                 }
4717
4718                 //NOTE: can't be cached persistently, depends on user settings
4719                 //NOTE: ContentHandler::getPageViewLanguage() may need to load the content to determine the page language!
4720                 $contentHandler = ContentHandler::getForTitle( $this );
4721                 $pageLang = $contentHandler->getPageViewLanguage( $this );
4722                 return $pageLang;
4723         }
4724 }