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                 ContentHandler::deprecated( __METHOD__, '1.21' );
 391
 392                 $content = ContentHandler::makeContent( $text, null, CONTENT_MODEL_WIKITEXT );
 393                 return $content->getRedirectTarget();
 394         }
 395
 396         /**
 397          * Extract a redirect destination from a string and return the
 398          * Title, or null if the text doesn't contain a valid redirect
 399          * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
 400          * in order to provide (hopefully) the Title of the final destination instead of another redirect
 401          *
 402          * @param $text String Text with possible redirect
 403          * @return Title
 404          * @deprecated since 1.21, use Content::getUltimateRedirectTarget instead.
 405          */
 406         public static function newFromRedirectRecurse( $text ) {
 407                 ContentHandler::deprecated( __METHOD__, '1.21' );
 408
 409                 $content = ContentHandler::makeContent( $text, null, CONTENT_MODEL_WIKITEXT );
 410                 return $content->getUltimateRedirectTarget();
 411         }
 412
 413         /**
 414          * Extract a redirect destination from a string and return an
 415          * array of Titles, or null if the text doesn't contain a valid redirect
 416          * The last element in the array is the final destination after all redirects
 417          * have been resolved (up to $wgMaxRedirects times)
 418          *
 419          * @param $text String Text with possible redirect
 420          * @return Array of Titles, with the destination last
 421          * @deprecated since 1.21, use Content::getRedirectChain instead.
 422          */
 423         public static function newFromRedirectArray( $text ) {
 424                 ContentHandler::deprecated( __METHOD__, '1.21' );
 425
 426                 $content = ContentHandler::makeContent( $text, null, CONTENT_MODEL_WIKITEXT );
 427                 return $content->getRedirectChain();
 428         }
 429
 430         /**
 431          * Get the prefixed DB key associated with an ID
 432          *
 433          * @param $id Int the page_id of the article
 434          * @return Title an object representing the article, or NULL if no such article was found
 435          */
 436         public static function nameOf( $id ) {
 437                 $dbr = wfGetDB( DB_SLAVE );
 438
 439                 $s = $dbr->selectRow(
 440                         'page',
 441                         array( 'page_namespace', 'page_title' ),
 442                         array( 'page_id' => $id ),
 443                         __METHOD__
 444                 );
 445                 if ( $s === false ) {
 446                         return null;
 447                 }
 448
 449                 $n = self::makeName( $s->page_namespace, $s->page_title );
 450                 return $n;
 451         }
 452
 453         /**
 454          * Get a regex character class describing the legal characters in a link
 455          *
 456          * @return String the list of characters, not delimited
 457          */
 458         public static function legalChars() {
 459                 global $wgLegalTitleChars;
 460                 return $wgLegalTitleChars;
 461         }
 462
 463         /**
 464          * Returns a simple regex that will match on characters and sequences invalid in titles.
 465          * Note that this doesn't pick up many things that could be wrong with titles, but that
 466          * replacing this regex with something valid will make many titles valid.
 467          *
 468          * @return String regex string
 469          */
 470         static function getTitleInvalidRegex() {
 471                 static $rxTc = false;
 472                 if ( !$rxTc ) {
 473                         # Matching titles will be held as illegal.
 474                         $rxTc = '/' .
 475                                 # Any character not allowed is forbidden...
 476                                 '[^' . self::legalChars() . ']' .
 477                                 # URL percent encoding sequences interfere with the ability
 478                                 # to round-trip titles -- you can't link to them consistently.
 479                                 '|%[0-9A-Fa-f]{2}' .
 480                                 # XML/HTML character references produce similar issues.
 481                                 '|&[A-Za-z0-9\x80-\xff]+;' .
 482                                 '|&#[0-9]+;' .
 483                                 '|&#x[0-9A-Fa-f]+;' .
 484                                 '/S';
 485                 }
 486
 487                 return $rxTc;
 488         }
 489
 490         /**
 491          * Get a string representation of a title suitable for
 492          * including in a search index
 493          *
 494          * @param $ns Int a namespace index
 495          * @param $title String text-form main part
 496          * @return String a stripped-down title string ready for the search index
 497          */
 498         public static function indexTitle( $ns, $title ) {
 499                 global $wgContLang;
 500
 501                 $lc = SearchEngine::legalSearchChars() . '&#;';
 502                 $t = $wgContLang->normalizeForSearch( $title );
 503                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 504                 $t = $wgContLang->lc( $t );
 505
 506                 # Handle 's, s'
 507                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 508                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 509
 510                 $t = preg_replace( "/\\s+/", ' ', $t );
 511
 512                 if ( $ns == NS_FILE ) {
 513                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 514                 }
 515                 return trim( $t );
 516         }
 517
 518         /**
 519          * Make a prefixed DB key from a DB key and a namespace index
 520          *
 521          * @param $ns Int numerical representation of the namespace
 522          * @param $title String the DB key form the title
 523          * @param $fragment String The link fragment (after the "#")
 524          * @param $interwiki String The interwiki prefix
 525          * @return String the prefixed form of the title
 526          */
 527         public static function makeName( $ns, $title, $fragment = '', $interwiki = '' ) {
 528                 global $wgContLang;
 529
 530                 $namespace = $wgContLang->getNsText( $ns );
 531                 $name = $namespace == '' ? $title : "$namespace:$title";
 532                 if ( strval( $interwiki ) != '' ) {
 533                         $name = "$interwiki:$name";
 534                 }
 535                 if ( strval( $fragment ) != '' ) {
 536                         $name .= '#' . $fragment;
 537                 }
 538                 return $name;
 539         }
 540
 541         /**
 542          * Escape a text fragment, say from a link, for a URL
 543          *
 544          * @param $fragment string containing a URL or link fragment (after the "#")
 545          * @return String: escaped string
 546          */
 547         static function escapeFragmentForURL( $fragment ) {
 548                 # Note that we don't urlencode the fragment.  urlencoded Unicode
 549                 # fragments appear not to work in IE (at least up to 7) or in at least
 550                 # one version of Opera 9.x.  The W3C validator, for one, doesn't seem
 551                 # to care if they aren't encoded.
 552                 return Sanitizer::escapeId( $fragment, 'noninitial' );
 553         }
 554
 555         /**
 556          * Callback for usort() to do title sorts by (namespace, title)
 557          *
 558          * @param $a Title
 559          * @param $b Title
 560          *
 561          * @return Integer: result of string comparison, or namespace comparison
 562          */
 563         public static function compare( $a, $b ) {
 564                 if ( $a->getNamespace() == $b->getNamespace() ) {
 565                         return strcmp( $a->getText(), $b->getText() );
 566                 } else {
 567                         return $a->getNamespace() - $b->getNamespace();
 568                 }
 569         }
 570
 571         /**
 572          * Determine whether the object refers to a page within
 573          * this project.
 574          *
 575          * @return Bool TRUE if this is an in-project interwiki link or a wikilink, FALSE otherwise
 576          */
 577         public function isLocal() {
 578                 if ( $this->mInterwiki != '' ) {
 579                         return Interwiki::fetch( $this->mInterwiki )->isLocal();
 580                 } else {
 581                         return true;
 582                 }
 583         }
 584
 585         /**
 586          * Is this Title interwiki?
 587          *
 588          * @return Bool
 589          */
 590         public function isExternal() {
 591                 return ( $this->mInterwiki != '' );
 592         }
 593
 594         /**
 595          * Get the interwiki prefix (or null string)
 596          *
 597          * @return String Interwiki prefix
 598          */
 599         public function getInterwiki() {
 600                 return $this->mInterwiki;
 601         }
 602
 603         /**
 604          * Determine whether the object refers to a page within
 605          * this project and is transcludable.
 606          *
 607          * @return Bool TRUE if this is transcludable
 608          */
 609         public function isTrans() {
 610                 if ( $this->mInterwiki == '' ) {
 611                         return false;
 612                 }
 613
 614                 return Interwiki::fetch( $this->mInterwiki )->isTranscludable();
 615         }
 616
 617         /**
 618          * Returns the DB name of the distant wiki which owns the object.
 619          *
 620          * @return String the DB name
 621          */
 622         public function getTransWikiID() {
 623                 if ( $this->mInterwiki == '' ) {
 624                         return false;
 625                 }
 626
 627                 return Interwiki::fetch( $this->mInterwiki )->getWikiID();
 628         }
 629
 630         /**
 631          * Get the text form (spaces not underscores) of the main part
 632          *
 633          * @return String Main part of the title
 634          */
 635         public function getText() {
 636                 return $this->mTextform;
 637         }
 638
 639         /**
 640          * Get the URL-encoded form of the main part
 641          *
 642          * @return String Main part of the title, URL-encoded
 643          */
 644         public function getPartialURL() {
 645                 return $this->mUrlform;
 646         }
 647
 648         /**
 649          * Get the main part with underscores
 650          *
 651          * @return String: Main part of the title, with underscores
 652          */
 653         public function getDBkey() {
 654                 return $this->mDbkeyform;
 655         }
 656
 657         /**
 658          * Get the DB key with the initial letter case as specified by the user
 659          *
 660          * @return String DB key
 661          */
 662         function getUserCaseDBKey() {
 663                 return $this->mUserCaseDBKey;
 664         }
 665
 666         /**
 667          * Get the namespace index, i.e. one of the NS_xxxx constants.
 668          *
 669          * @return Integer: Namespace index
 670          */
 671         public function getNamespace() {
 672                 return $this->mNamespace;
 673         }
 674
 675         /**
 676          * Get the page's content model id, see the CONTENT_MODEL_XXX constants.
 677          *
 678          * @return String: Content model id
 679          */
 680         public function getContentModel() {
 681                 if ( !$this->mContentModel ) {
 682                         $linkCache = LinkCache::singleton();
 683                         $this->mContentModel = $linkCache->getGoodLinkFieldObj( $this, 'model' );
 684                 }
 685
 686                 if ( !$this->mContentModel ) {
 687                         $this->mContentModel = ContentHandler::getDefaultModelFor( $this );
 688                 }
 689
 690                 if( !$this->mContentModel ) {
 691                         throw new MWException( "failed to determin content model!" );
 692                 }
 693
 694                 return $this->mContentModel;
 695         }
 696
 697         /**
 698          * Convenience method for checking a title's content model name
 699          *
 700          * @param String $id The content model ID (use the CONTENT_MODEL_XXX constants).
 701          * @return Boolean true if $this->getContentModel() == $id
 702          */
 703         public function hasContentModel( $id ) {
 704                 return $this->getContentModel() == $id;
 705         }
 706
 707         /**
 708          * Get the namespace text
 709          *
 710          * @return String: Namespace text
 711          */
 712         public function getNsText() {
 713                 global $wgContLang;
 714
 715                 if ( $this->mInterwiki != '' ) {
 716                         // This probably shouldn't even happen. ohh man, oh yuck.
 717                         // But for interwiki transclusion it sometimes does.
 718                         // Shit. Shit shit shit.
 719                         //
 720                         // Use the canonical namespaces if possible to try to
 721                         // resolve a foreign namespace.
 722                         if ( MWNamespace::exists( $this->mNamespace ) ) {
 723                                 return MWNamespace::getCanonicalName( $this->mNamespace );
 724                         }
 725                 }
 726
 727                 if ( $wgContLang->needsGenderDistinction() &&
 728                                 MWNamespace::hasGenderDistinction( $this->mNamespace ) ) {
 729                         $gender = GenderCache::singleton()->getGenderOf( $this->getText(), __METHOD__ );
 730                         return $wgContLang->getGenderNsText( $this->mNamespace, $gender );
 731                 }
 732
 733                 return $wgContLang->getNsText( $this->mNamespace );
 734         }
 735
 736         /**
 737          * Get the namespace text of the subject (rather than talk) page
 738          *
 739          * @return String Namespace text
 740          */
 741         public function getSubjectNsText() {
 742                 global $wgContLang;
 743                 return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
 744         }
 745
 746         /**
 747          * Get the namespace text of the talk page
 748          *
 749          * @return String Namespace text
 750          */
 751         public function getTalkNsText() {
 752                 global $wgContLang;
 753                 return( $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) ) );
 754         }
 755
 756         /**
 757          * Could this title have a corresponding talk page?
 758          *
 759          * @return Bool TRUE or FALSE
 760          */
 761         public function canTalk() {
 762                 return( MWNamespace::canTalk( $this->mNamespace ) );
 763         }
 764
 765         /**
 766          * Is this in a namespace that allows actual pages?
 767          *
 768          * @return Bool
 769          * @internal note -- uses hardcoded namespace index instead of constants
 770          */
 771         public function canExist() {
 772                 return $this->mNamespace >= NS_MAIN;
 773         }
 774
 775         /**
 776          * Can this title be added to a user's watchlist?
 777          *
 778          * @return Bool TRUE or FALSE
 779          */
 780         public function isWatchable() {
 781                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
 782         }
 783
 784         /**
 785          * Returns true if this is a special page.
 786          *
 787          * @return boolean
 788          */
 789         public function isSpecialPage() {
 790                 return $this->getNamespace() == NS_SPECIAL;
 791         }
 792
 793         /**
 794          * Returns true if this title resolves to the named special page
 795          *
 796          * @param $name String The special page name
 797          * @return boolean
 798          */
 799         public function isSpecial( $name ) {
 800                 if ( $this->isSpecialPage() ) {
 801                         list( $thisName, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $this->getDBkey() );
 802                         if ( $name == $thisName ) {
 803                                 return true;
 804                         }
 805                 }
 806                 return false;
 807         }
 808
 809         /**
 810          * If the Title refers to a special page alias which is not the local default, resolve
 811          * the alias, and localise the name as necessary.  Otherwise, return $this
 812          *
 813          * @return Title
 814          */
 815         public function fixSpecialName() {
 816                 if ( $this->isSpecialPage() ) {
 817                         list( $canonicalName, $par ) = SpecialPageFactory::resolveAlias( $this->mDbkeyform );
 818                         if ( $canonicalName ) {
 819                                 $localName = SpecialPageFactory::getLocalNameFor( $canonicalName, $par );
 820                                 if ( $localName != $this->mDbkeyform ) {
 821                                         return Title::makeTitle( NS_SPECIAL, $localName );
 822                                 }
 823                         }
 824                 }
 825                 return $this;
 826         }
 827
 828         /**
 829          * Returns true if the title is inside the specified namespace.
 830          *
 831          * Please make use of this instead of comparing to getNamespace()
 832          * This function is much more resistant to changes we may make
 833          * to namespaces than code that makes direct comparisons.
 834          * @param $ns int The namespace
 835          * @return bool
 836          * @since 1.19
 837          */
 838         public function inNamespace( $ns ) {
 839                 return MWNamespace::equals( $this->getNamespace(), $ns );
 840         }
 841
 842         /**
 843          * Returns true if the title is inside one of the specified namespaces.
 844          *
 845          * @param ...$namespaces The namespaces to check for
 846          * @return bool
 847          * @since 1.19
 848          */
 849         public function inNamespaces( /* ... */ ) {
 850                 $namespaces = func_get_args();
 851                 if ( count( $namespaces ) > 0 && is_array( $namespaces[0] ) ) {
 852                         $namespaces = $namespaces[0];
 853                 }
 854
 855                 foreach ( $namespaces as $ns ) {
 856                         if ( $this->inNamespace( $ns ) ) {
 857                                 return true;
 858                         }
 859                 }
 860
 861                 return false;
 862         }
 863
 864         /**
 865          * Returns true if the title has the same subject namespace as the
 866          * namespace specified.
 867          * For example this method will take NS_USER and return true if namespace
 868          * is either NS_USER or NS_USER_TALK since both of them have NS_USER
 869          * as their subject namespace.
 870          *
 871          * This is MUCH simpler than individually testing for equivilance
 872          * against both NS_USER and NS_USER_TALK, and is also forward compatible.
 873          * @since 1.19
 874          * @param $ns int
 875          * @return bool
 876          */
 877         public function hasSubjectNamespace( $ns ) {
 878                 return MWNamespace::subjectEquals( $this->getNamespace(), $ns );
 879         }
 880
 881         /**
 882          * Is this Title in a namespace which contains content?
 883          * In other words, is this a content page, for the purposes of calculating
 884          * statistics, etc?
 885          *
 886          * @return Boolean
 887          */
 888         public function isContentPage() {
 889                 return MWNamespace::isContent( $this->getNamespace() );
 890         }
 891
 892         /**
 893          * Would anybody with sufficient privileges be able to move this page?
 894          * Some pages just aren't movable.
 895          *
 896          * @return Bool TRUE or FALSE
 897          */
 898         public function isMovable() {
 899                 if ( !MWNamespace::isMovable( $this->getNamespace() ) || $this->getInterwiki() != '' ) {
 900                         // Interwiki title or immovable namespace. Hooks don't get to override here
 901                         return false;
 902                 }
 903
 904                 $result = true;
 905                 wfRunHooks( 'TitleIsMovable', array( $this, &$result ) );
 906                 return $result;
 907         }
 908
 909         /**
 910          * Is this the mainpage?
 911          * @note Title::newFromText seams to be sufficiently optimized by the title
 912          * cache that we don't need to over-optimize by doing direct comparisons and
 913          * acidentally creating new bugs where $title->equals( Title::newFromText() )
 914          * ends up reporting something differently than $title->isMainPage();
 915          *
 916          * @since 1.18
 917          * @return Bool
 918          */
 919         public function isMainPage() {
 920                 return $this->equals( Title::newMainPage() );
 921         }
 922
 923         /**
 924          * Is this a subpage?
 925          *
 926          * @return Bool
 927          */
 928         public function isSubpage() {
 929                 return MWNamespace::hasSubpages( $this->mNamespace )
 930                         ? strpos( $this->getText(), '/' ) !== false
 931                         : false;
 932         }
 933
 934         /**
 935          * Is this a conversion table for the LanguageConverter?
 936          *
 937          * @return Bool
 938          */
 939         public function isConversionTable() {
 940                 //@todo: ConversionTable should become a separate content model.
 941
 942                 return $this->getNamespace() == NS_MEDIAWIKI &&
 943                         strpos( $this->getText(), 'Conversiontable/' ) === 0;
 944         }
 945
 946         /**
 947          * Does that page contain wikitext, or it is JS, CSS or whatever?
 948          *
 949          * @return Bool
 950          */
 951         public function isWikitextPage() {
 952                 return $this->hasContentModel( CONTENT_MODEL_WIKITEXT );
 953         }
 954
 955         /**
 956          * Could this page contain custom CSS or JavaScript for the global UI.
 957          * This is generally true for pages in the MediaWiki namespace having CONTENT_MODEL_CSS
 958          * or CONTENT_MODEL_JAVASCRIPT.
 959          *
 960          * This method does *not* return true for per-user JS/CSS. Use isCssJsSubpage() for that!
 961          *
 962          * Note that this method should not return true for pages that contain and show "inactive" CSS or JS.
 963          *
 964          * @return Bool
 965          */
 966         public function isCssOrJsPage() {
 967                 $isCssOrJsPage = NS_MEDIAWIKI == $this->mNamespace
 968                         && ( $this->hasContentModel( CONTENT_MODEL_CSS )
 969                                 || $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
 970
 971                 #NOTE: this hook is also called in ContentHandler::getDefaultModel. It's called here again to make sure
 972                 #      hook funktions can force this method to return true even outside the mediawiki namespace.
 973
 974                 wfRunHooks( 'TitleIsCssOrJsPage', array( $this, &$isCssOrJsPage ) );
 975
 976                 return $isCssOrJsPage;
 977         }
 978
 979         /**
 980          * Is this a .css or .js subpage of a user page?
 981          * @return Bool
 982          */
 983         public function isCssJsSubpage() {
 984                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
 985                                 && ( $this->hasContentModel( CONTENT_MODEL_CSS )
 986                                         || $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) ) );
 987         }
 988
 989         /**
 990          * Trim down a .css or .js subpage title to get the corresponding skin name
 991          *
 992          * @return string containing skin name from .css or .js subpage title
 993          */
 994         public function getSkinFromCssJsSubpage() {
 995                 $subpage = explode( '/', $this->mTextform );
 996                 $subpage = $subpage[ count( $subpage ) - 1 ];
 997                 $lastdot = strrpos( $subpage, '.' );
 998                 if ( $lastdot === false )
 999                         return $subpage; # Never happens: only called for names ending in '.css' or '.js'
1000                 return substr( $subpage, 0, $lastdot );
1001         }
1002
1003         /**
1004          * Is this a .css subpage of a user page?
1005          *
1006          * @return Bool
1007          */
1008         public function isCssSubpage() {
1009                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
1010                         && $this->hasContentModel( CONTENT_MODEL_CSS ) );
1011         }
1012
1013         /**
1014          * Is this a .js subpage of a user page?
1015          *
1016          * @return Bool
1017          */
1018         public function isJsSubpage() {
1019                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
1020                         && $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
1021         }
1022
1023         /**
1024          * Is this a talk page of some sort?
1025          *
1026          * @return Bool
1027          */
1028         public function isTalkPage() {
1029                 return MWNamespace::isTalk( $this->getNamespace() );
1030         }
1031
1032         /**
1033          * Get a Title object associated with the talk page of this article
1034          *
1035          * @return Title the object for the talk page
1036          */
1037         public function getTalkPage() {
1038                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1039         }
1040
1041         /**
1042          * Get a title object associated with the subject page of this
1043          * talk page
1044          *
1045          * @return Title the object for the subject page
1046          */
1047         public function getSubjectPage() {
1048                 // Is this the same title?
1049                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
1050                 if ( $this->getNamespace() == $subjectNS ) {
1051                         return $this;
1052                 }
1053                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
1054         }
1055
1056         /**
1057          * Get the default namespace index, for when there is no namespace
1058          *
1059          * @return Int Default namespace index
1060          */
1061         public function getDefaultNamespace() {
1062                 return $this->mDefaultNamespace;
1063         }
1064
1065         /**
1066          * Get title for search index
1067          *
1068          * @return String a stripped-down title string ready for the
1069          *  search index
1070          */
1071         public function getIndexTitle() {
1072                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
1073         }
1074
1075         /**
1076          * Get the Title fragment (i.e.\ the bit after the #) in text form
1077          *
1078          * @return String Title fragment
1079          */
1080         public function getFragment() {
1081                 return $this->mFragment;
1082         }
1083
1084         /**
1085          * Get the fragment in URL form, including the "#" character if there is one
1086          * @return String Fragment in URL form
1087          */
1088         public function getFragmentForURL() {
1089                 if ( $this->mFragment == '' ) {
1090                         return '';
1091                 } else {
1092                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
1093                 }
1094         }
1095
1096         /**
1097          * Set the fragment for this title. Removes the first character from the
1098          * specified fragment before setting, so it assumes you're passing it with
1099          * an initial "#".
1100          *
1101          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
1102          * Still in active use privately.
1103          *
1104          * @param $fragment String text
1105          */
1106         public function setFragment( $fragment ) {
1107                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
1108         }
1109
1110         /**
1111          * Prefix some arbitrary text with the namespace or interwiki prefix
1112          * of this object
1113          *
1114          * @param $name String the text
1115          * @return String the prefixed text
1116          * @private
1117          */
1118         private function prefix( $name ) {
1119                 $p = '';
1120                 if ( $this->mInterwiki != '' ) {
1121                         $p = $this->mInterwiki . ':';
1122                 }
1123
1124                 if ( 0 != $this->mNamespace ) {
1125                         $p .= $this->getNsText() . ':';
1126                 }
1127                 return $p . $name;
1128         }
1129
1130         /**
1131          * Get the prefixed database key form
1132          *
1133          * @return String the prefixed title, with underscores and
1134          *  any interwiki and namespace prefixes
1135          */
1136         public function getPrefixedDBkey() {
1137                 $s = $this->prefix( $this->mDbkeyform );
1138                 $s = str_replace( ' ', '_', $s );
1139                 return $s;
1140         }
1141
1142         /**
1143          * Get the prefixed title with spaces.
1144          * This is the form usually used for display
1145          *
1146          * @return String the prefixed title, with spaces
1147          */
1148         public function getPrefixedText() {
1149                 // @todo FIXME: Bad usage of empty() ?
1150                 if ( empty( $this->mPrefixedText ) ) {
1151                         $s = $this->prefix( $this->mTextform );
1152                         $s = str_replace( '_', ' ', $s );
1153                         $this->mPrefixedText = $s;
1154                 }
1155                 return $this->mPrefixedText;
1156         }
1157
1158         /**
1159          * Return a string representation of this title
1160          *
1161          * @return String representation of this title
1162          */
1163         public function __toString() {
1164                 return $this->getPrefixedText();
1165         }
1166
1167         /**
1168          * Get the prefixed title with spaces, plus any fragment
1169          * (part beginning with '#')
1170          *
1171          * @return String the prefixed title, with spaces and the fragment, including '#'
1172          */
1173         public function getFullText() {
1174                 $text = $this->getPrefixedText();
1175                 if ( $this->mFragment != '' ) {
1176                         $text .= '#' . $this->mFragment;
1177                 }
1178                 return $text;
1179         }
1180
1181         /**
1182          * Get the root page name text without a namespace, i.e. the leftmost part before any slashes
1183          *
1184          * @par Example:
1185          * @code
1186          * Title::newFromText('User:Foo/Bar/Baz')->getRootText();
1187          * # returns: 'Foo'
1188          * @endcode
1189          *
1190          * @return String Root name
1191          * @since 1.20
1192          */
1193         public function getRootText() {
1194                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1195                         return $this->getText();
1196                 }
1197
1198                 return strtok( $this->getText(), '/' );
1199         }
1200
1201         /**
1202          * Get the root page name title, i.e. the leftmost part before any slashes
1203          *
1204          * @par Example:
1205          * @code
1206          * Title::newFromText('User:Foo/Bar/Baz')->getRootTitle();
1207          * # returns: Title{User:Foo}
1208          * @endcode
1209          *
1210          * @return Title Root title
1211          * @since 1.20
1212          */
1213         public function getRootTitle() {
1214                 return Title::makeTitle( $this->getNamespace(), $this->getRootText() );
1215         }
1216
1217         /**
1218          * Get the base page name without a namespace, i.e. the part before the subpage name
1219          *
1220          * @par Example:
1221          * @code
1222          * Title::newFromText('User:Foo/Bar/Baz')->getBaseText();
1223          * # returns: 'Foo/Bar'
1224          * @endcode
1225          *
1226          * @return String Base name
1227          */
1228         public function getBaseText() {
1229                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1230                         return $this->getText();
1231                 }
1232
1233                 $parts = explode( '/', $this->getText() );
1234                 # Don't discard the real title if there's no subpage involved
1235                 if ( count( $parts ) > 1 ) {
1236                         unset( $parts[count( $parts ) - 1] );
1237                 }
1238                 return implode( '/', $parts );
1239         }
1240
1241         /**
1242          * Get the base page name title, i.e. the part before the subpage name
1243          *
1244          * @par Example:
1245          * @code
1246          * Title::newFromText('User:Foo/Bar/Baz')->getBaseTitle();
1247          * # returns: Title{User:Foo/Bar}
1248          * @endcode
1249          *
1250          * @return Title Base title
1251          * @since 1.20
1252          */
1253         public function getBaseTitle() {
1254                 return Title::makeTitle( $this->getNamespace(), $this->getBaseText() );
1255         }
1256
1257         /**
1258          * Get the lowest-level subpage name, i.e. the rightmost part after any slashes
1259          *
1260          * @par Example:
1261          * @code
1262          * Title::newFromText('User:Foo/Bar/Baz')->getSubpageText();
1263          * # returns: "Baz"
1264          * @endcode
1265          *
1266          * @return String Subpage name
1267          */
1268         public function getSubpageText() {
1269                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1270                         return( $this->mTextform );
1271                 }
1272                 $parts = explode( '/', $this->mTextform );
1273                 return( $parts[count( $parts ) - 1] );
1274         }
1275
1276         /**
1277          * Get the title for a subpage of the current page
1278          *
1279          * @par Example:
1280          * @code
1281          * Title::newFromText('User:Foo/Bar/Baz')->getSubpage("Asdf");
1282          * # returns: Title{User:Foo/Bar/Baz/Asdf}
1283          * @endcode
1284          *
1285          * @param $text String The subpage name to add to the title
1286          * @return Title Subpage title
1287          * @since 1.20
1288          */
1289         public function getSubpage( $text ) {
1290                 return Title::makeTitleSafe( $this->getNamespace(), $this->getText() . '/' . $text );
1291         }
1292
1293         /**
1294          * Get the HTML-escaped displayable text form.
1295          * Used for the title field in <a> tags.
1296          *
1297          * @return String the text, including any prefixes
1298          */
1299         public function getEscapedText() {
1300                 wfDeprecated( __METHOD__, '1.19' );
1301                 return htmlspecialchars( $this->getPrefixedText() );
1302         }
1303
1304         /**
1305          * Get a URL-encoded form of the subpage text
1306          *
1307          * @return String URL-encoded subpage name
1308          */
1309         public function getSubpageUrlForm() {
1310                 $text = $this->getSubpageText();
1311                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
1312                 return( $text );
1313         }
1314
1315         /**
1316          * Get a URL-encoded title (not an actual URL) including interwiki
1317          *
1318          * @return String the URL-encoded form
1319          */
1320         public function getPrefixedURL() {
1321                 $s = $this->prefix( $this->mDbkeyform );
1322                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
1323                 return $s;
1324         }
1325
1326         /**
1327          * Helper to fix up the get{Local,Full,Link,Canonical}URL args
1328          * get{Canonical,Full,Link,Local}URL methods accepted an optional
1329          * second argument named variant. This was deprecated in favor
1330          * of passing an array of option with a "variant" key
1331          * Once $query2 is removed for good, this helper can be dropped
1332          * andthe wfArrayToCGI moved to getLocalURL();
1333          *
1334          * @since 1.19 (r105919)
1335          * @param $query
1336          * @param $query2 bool
1337          * @return String
1338          */
1339         private static function fixUrlQueryArgs( $query, $query2 = false ) {
1340                 if( $query2 !== false ) {
1341                         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" );
1342                 }
1343                 if ( is_array( $query ) ) {
1344                         $query = wfArrayToCGI( $query );
1345                 }
1346                 if ( $query2 ) {
1347                         if ( is_string( $query2 ) ) {
1348                                 // $query2 is a string, we will consider this to be
1349                                 // a deprecated $variant argument and add it to the query
1350                                 $query2 = wfArrayToCGI( array( 'variant' => $query2 ) );
1351                         } else {
1352                                 $query2 = wfArrayToCGI( $query2 );
1353                         }
1354                         // If we have $query content add a & to it first
1355                         if ( $query ) {
1356                                 $query .= '&';
1357                         }
1358                         // Now append the queries together
1359                         $query .= $query2;
1360                 }
1361                 return $query;
1362         }
1363
1364         /**
1365          * Get a real URL referring to this title, with interwiki link and
1366          * fragment
1367          *
1368          * See getLocalURL for the arguments.
1369          *
1370          * @see self::getLocalURL
1371          * @see wfExpandUrl
1372          * @param $proto Protocol type to use in URL
1373          * @return String the URL
1374          */
1375         public function getFullURL( $query = '', $query2 = false, $proto = PROTO_RELATIVE ) {
1376                 $query = self::fixUrlQueryArgs( $query, $query2 );
1377
1378                 # Hand off all the decisions on urls to getLocalURL
1379                 $url = $this->getLocalURL( $query );
1380
1381                 # Expand the url to make it a full url. Note that getLocalURL has the
1382                 # potential to output full urls for a variety of reasons, so we use
1383                 # wfExpandUrl instead of simply prepending $wgServer
1384                 $url = wfExpandUrl( $url, $proto );
1385
1386                 # Finally, add the fragment.
1387                 $url .= $this->getFragmentForURL();
1388
1389                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
1390                 return $url;
1391         }
1392
1393         /**
1394          * Get a URL with no fragment or server name.  If this page is generated
1395          * with action=render, $wgServer is prepended.
1396          *
1397
1398          * @param $query string|array an optional query string,
1399          *   not used for interwiki     links. Can be specified as an associative array as well,
1400          *   e.g., array( 'action' => 'edit' ) (keys and values will be URL-escaped).
1401          *   Some query patterns will trigger various shorturl path replacements.
1402          * @param $query2 Mixed: An optional secondary query array. This one MUST
1403          *   be an array. If a string is passed it will be interpreted as a deprecated
1404          *   variant argument and urlencoded into a variant= argument.
1405          *   This second query argument will be added to the $query
1406          *   The second parameter is deprecated since 1.19. Pass it as a key,value
1407          *   pair in the first parameter array instead.
1408          *
1409          * @return String the URL
1410          */
1411         public function getLocalURL( $query = '', $query2 = false ) {
1412                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
1413
1414                 $query = self::fixUrlQueryArgs( $query, $query2 );
1415
1416                 $interwiki = Interwiki::fetch( $this->mInterwiki );
1417                 if ( $interwiki ) {
1418                         $namespace = $this->getNsText();
1419                         if ( $namespace != '' ) {
1420                                 # Can this actually happen? Interwikis shouldn't be parsed.
1421                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
1422                                 $namespace .= ':';
1423                         }
1424                         $url = $interwiki->getURL( $namespace . $this->getDBkey() );
1425                         $url = wfAppendQuery( $url, $query );
1426                 } else {
1427                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
1428                         if ( $query == '' ) {
1429                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
1430                                 wfRunHooks( 'GetLocalURL::Article', array( &$this, &$url ) );
1431                         } else {
1432                                 global $wgVariantArticlePath, $wgActionPaths;
1433                                 $url = false;
1434                                 $matches = array();
1435
1436                                 if ( !empty( $wgActionPaths ) &&
1437                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
1438                                 {
1439                                         $action = urldecode( $matches[2] );
1440                                         if ( isset( $wgActionPaths[$action] ) ) {
1441                                                 $query = $matches[1];
1442                                                 if ( isset( $matches[4] ) ) {
1443                                                         $query .= $matches[4];
1444                                                 }
1445                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
1446                                                 if ( $query != '' ) {
1447                                                         $url = wfAppendQuery( $url, $query );
1448                                                 }
1449                                         }
1450                                 }
1451
1452                                 if ( $url === false &&
1453                                         $wgVariantArticlePath &&
1454                                         $this->getPageLanguage()->hasVariants() &&
1455                                         preg_match( '/^variant=([^&]*)$/', $query, $matches ) )
1456                                 {
1457                                         $variant = urldecode( $matches[1] );
1458                                         if ( $this->getPageLanguage()->hasVariant( $variant ) ) {
1459                                                 // Only do the variant replacement if the given variant is a valid
1460                                                 // variant for the page's language.
1461                                                 $url = str_replace( '$2', urlencode( $variant ), $wgVariantArticlePath );
1462                                                 $url = str_replace( '$1', $dbkey, $url );
1463                                         }
1464                                 }
1465
1466                                 if ( $url === false ) {
1467                                         if ( $query == '-' ) {
1468                                                 $query = '';
1469                                         }
1470                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
1471                                 }
1472                         }
1473
1474                         wfRunHooks( 'GetLocalURL::Internal', array( &$this, &$url, $query ) );
1475
1476                         // @todo FIXME: This causes breakage in various places when we
1477                         // actually expected a local URL and end up with dupe prefixes.
1478                         if ( $wgRequest->getVal( 'action' ) == 'render' ) {
1479                                 $url = $wgServer . $url;
1480                         }
1481                 }
1482                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
1483                 return $url;
1484         }
1485
1486         /**
1487          * Get a URL that's the simplest URL that will be valid to link, locally,
1488          * to the current Title.  It includes the fragment, but does not include
1489          * the server unless action=render is used (or the link is external).  If
1490          * there's a fragment but the prefixed text is empty, we just return a link
1491          * to the fragment.
1492          *
1493          * The result obviously should not be URL-escaped, but does need to be
1494          * HTML-escaped if it's being output in HTML.
1495          *
1496          * See getLocalURL for the arguments.
1497          *
1498          * @param $proto Protocol to use; setting this will cause a full URL to be used
1499          * @see self::getLocalURL
1500          * @return String the URL
1501          */
1502         public function getLinkURL( $query = '', $query2 = false, $proto = PROTO_RELATIVE ) {
1503                 wfProfileIn( __METHOD__ );
1504                 if ( $this->isExternal() || $proto !== PROTO_RELATIVE ) {
1505                         $ret = $this->getFullURL( $query, $query2, $proto );
1506                 } elseif ( $this->getPrefixedText() === '' && $this->getFragment() !== '' ) {
1507                         $ret = $this->getFragmentForURL();
1508                 } else {
1509                         $ret = $this->getLocalURL( $query, $query2 ) . $this->getFragmentForURL();
1510                 }
1511                 wfProfileOut( __METHOD__ );
1512                 return $ret;
1513         }
1514
1515         /**
1516          * Get an HTML-escaped version of the URL form, suitable for
1517          * using in a link, without a server name or fragment
1518          *
1519          * See getLocalURL for the arguments.
1520          *
1521          * @see self::getLocalURL
1522          * @param $query string
1523          * @param $query2 bool|string
1524          * @return String the URL
1525          */
1526         public function escapeLocalURL( $query = '', $query2 = false ) {
1527                 wfDeprecated( __METHOD__, '1.19' );
1528                 return htmlspecialchars( $this->getLocalURL( $query, $query2 ) );
1529         }
1530
1531         /**
1532          * Get an HTML-escaped version of the URL form, suitable for
1533          * using in a link, including the server name and fragment
1534          *
1535          * See getLocalURL for the arguments.
1536          *
1537          * @see self::getLocalURL
1538          * @return String the URL
1539          */
1540         public function escapeFullURL( $query = '', $query2 = false ) {
1541                 wfDeprecated( __METHOD__, '1.19' );
1542                 return htmlspecialchars( $this->getFullURL( $query, $query2 ) );
1543         }
1544
1545         /**
1546          * Get the URL form for an internal link.
1547          * - Used in various Squid-related code, in case we have a different
1548          * internal hostname for the server from the exposed one.
1549          *
1550          * This uses $wgInternalServer to qualify the path, or $wgServer
1551          * if $wgInternalServer is not set. If the server variable used is
1552          * protocol-relative, the URL will be expanded to http://
1553          *
1554          * See getLocalURL for the arguments.
1555          *
1556          * @see self::getLocalURL
1557          * @return String the URL
1558          */
1559         public function getInternalURL( $query = '', $query2 = false ) {
1560                 global $wgInternalServer, $wgServer;
1561                 $query = self::fixUrlQueryArgs( $query, $query2 );
1562                 $server = $wgInternalServer !== false ? $wgInternalServer : $wgServer;
1563                 $url = wfExpandUrl( $server . $this->getLocalURL( $query ), PROTO_HTTP );
1564                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
1565                 return $url;
1566         }
1567
1568         /**
1569          * Get the URL for a canonical link, for use in things like IRC and
1570          * e-mail notifications. Uses $wgCanonicalServer and the
1571          * GetCanonicalURL hook.
1572          *
1573          * NOTE: Unlike getInternalURL(), the canonical URL includes the fragment
1574          *
1575          * See getLocalURL for the arguments.
1576          *
1577          * @see self::getLocalURL
1578          * @return string The URL
1579          * @since 1.18
1580          */
1581         public function getCanonicalURL( $query = '', $query2 = false ) {
1582                 $query = self::fixUrlQueryArgs( $query, $query2 );
1583                 $url = wfExpandUrl( $this->getLocalURL( $query ) . $this->getFragmentForURL(), PROTO_CANONICAL );
1584                 wfRunHooks( 'GetCanonicalURL', array( &$this, &$url, $query ) );
1585                 return $url;
1586         }
1587
1588         /**
1589          * HTML-escaped version of getCanonicalURL()
1590          *
1591          * See getLocalURL for the arguments.
1592          *
1593          * @see self::getLocalURL
1594          * @since 1.18
1595          * @return string
1596          */
1597         public function escapeCanonicalURL( $query = '', $query2 = false ) {
1598                 wfDeprecated( __METHOD__, '1.19' );
1599                 return htmlspecialchars( $this->getCanonicalURL( $query, $query2 ) );
1600         }
1601
1602         /**
1603          * Get the edit URL for this Title
1604          *
1605          * @return String the URL, or a null string if this is an
1606          *  interwiki link
1607          */
1608         public function getEditURL() {
1609                 if ( $this->mInterwiki != '' ) {
1610                         return '';
1611                 }
1612                 $s = $this->getLocalURL( 'action=edit' );
1613
1614                 return $s;
1615         }
1616
1617         /**
1618          * Is $wgUser watching this page?
1619          *
1620          * @deprecated in 1.20; use User::isWatched() instead.
1621          * @return Bool
1622          */
1623         public function userIsWatching() {
1624                 global $wgUser;
1625
1626                 if ( is_null( $this->mWatched ) ) {
1627                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn() ) {
1628                                 $this->mWatched = false;
1629                         } else {
1630                                 $this->mWatched = $wgUser->isWatched( $this );
1631                         }
1632                 }
1633                 return $this->mWatched;
1634         }
1635
1636         /**
1637          * Can $wgUser read this page?
1638          *
1639          * @deprecated in 1.19; use userCan(), quickUserCan() or getUserPermissionsErrors() instead
1640          * @return Bool
1641          * @todo fold these checks into userCan()
1642          */
1643         public function userCanRead() {
1644                 wfDeprecated( __METHOD__, '1.19' );
1645                 return $this->userCan( 'read' );
1646         }
1647
1648         /**
1649          * Can $user perform $action on this page?
1650          * This skips potentially expensive cascading permission checks
1651          * as well as avoids expensive error formatting
1652          *
1653          * Suitable for use for nonessential UI controls in common cases, but
1654          * _not_ for functional access control.
1655          *
1656          * May provide false positives, but should never provide a false negative.
1657          *
1658          * @param $action String action that permission needs to be checked for
1659          * @param $user User to check (since 1.19); $wgUser will be used if not
1660          *              provided.
1661          * @return Bool
1662          */
1663         public function quickUserCan( $action, $user = null ) {
1664                 return $this->userCan( $action, $user, false );
1665         }
1666
1667         /**
1668          * Can $user perform $action on this page?
1669          *
1670          * @param $action String action that permission needs to be checked for
1671          * @param $user User to check (since 1.19); $wgUser will be used if not
1672          *   provided.
1673          * @param $doExpensiveQueries Bool Set this to false to avoid doing
1674          *   unnecessary queries.
1675          * @return Bool
1676          */
1677         public function userCan( $action, $user = null, $doExpensiveQueries = true ) {
1678                 if ( !$user instanceof User ) {
1679                         global $wgUser;
1680                         $user = $wgUser;
1681                 }
1682                 return !count( $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries, true ) );
1683         }
1684
1685         /**
1686          * Can $user perform $action on this page?
1687          *
1688          * @todo FIXME: This *does not* check throttles (User::pingLimiter()).
1689          *
1690          * @param $action String action that permission needs to be checked for
1691          * @param $user User to check
1692          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary
1693          *   queries by skipping checks for cascading protections and user blocks.
1694          * @param $ignoreErrors Array of Strings Set this to a list of message keys
1695          *   whose corresponding errors may be ignored.
1696          * @return Array of arguments to wfMessage to explain permissions problems.
1697          */
1698         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1699                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1700
1701                 // Remove the errors being ignored.
1702                 foreach ( $errors as $index => $error ) {
1703                         $error_key = is_array( $error ) ? $error[0] : $error;
1704
1705                         if ( in_array( $error_key, $ignoreErrors ) ) {
1706                                 unset( $errors[$index] );
1707                         }
1708                 }
1709
1710                 return $errors;
1711         }
1712
1713         /**
1714          * Permissions checks that fail most often, and which are easiest to test.
1715          *
1716          * @param $action String the action to check
1717          * @param $user User user to check
1718          * @param $errors Array list of current errors
1719          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1720          * @param $short Boolean short circuit on first error
1721          *
1722          * @return Array list of errors
1723          */
1724         private function checkQuickPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1725                 if ( $action == 'create' ) {
1726                         if ( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1727                                  ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1728                                 $errors[] = $user->isAnon() ? array( 'nocreatetext' ) : array( 'nocreate-loggedin' );
1729                         }
1730                 } elseif ( $action == 'move' ) {
1731                         if ( !$user->isAllowed( 'move-rootuserpages' )
1732                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1733                                 // Show user page-specific message only if the user can move other pages
1734                                 $errors[] = array( 'cant-move-user-page' );
1735                         }
1736
1737                         // Check if user is allowed to move files if it's a file
1738                         if ( $this->mNamespace == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1739                                 $errors[] = array( 'movenotallowedfile' );
1740                         }
1741
1742                         if ( !$user->isAllowed( 'move' ) ) {
1743                                 // User can't move anything
1744                                 $userCanMove = User::groupHasPermission( 'user', 'move' );
1745                                 $autoconfirmedCanMove = User::groupHasPermission( 'autoconfirmed', 'move' );
1746                                 if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
1747                                         // custom message if logged-in users without any special rights can move
1748                                         $errors[] = array( 'movenologintext' );
1749                                 } else {
1750                                         $errors[] = array( 'movenotallowed' );
1751                                 }
1752                         }
1753                 } elseif ( $action == 'move-target' ) {
1754                         if ( !$user->isAllowed( 'move' ) ) {
1755                                 // User can't move anything
1756                                 $errors[] = array( 'movenotallowed' );
1757                         } elseif ( !$user->isAllowed( 'move-rootuserpages' )
1758                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1759                                 // Show user page-specific message only if the user can move other pages
1760                                 $errors[] = array( 'cant-move-to-user-page' );
1761                         }
1762                 } elseif ( !$user->isAllowed( $action ) ) {
1763                         $errors[] = $this->missingPermissionError( $action, $short );
1764                 }
1765
1766                 return $errors;
1767         }
1768
1769         /**
1770          * Add the resulting error code to the errors array
1771          *
1772          * @param $errors Array list of current errors
1773          * @param $result Mixed result of errors
1774          *
1775          * @return Array list of errors
1776          */
1777         private function resultToError( $errors, $result ) {
1778                 if ( is_array( $result ) && count( $result ) && !is_array( $result[0] ) ) {
1779                         // A single array representing an error
1780                         $errors[] = $result;
1781                 } elseif ( is_array( $result ) && is_array( $result[0] ) ) {
1782                         // A nested array representing multiple errors
1783                         $errors = array_merge( $errors, $result );
1784                 } elseif ( $result !== '' && is_string( $result ) ) {
1785                         // A string representing a message-id
1786                         $errors[] = array( $result );
1787                 } elseif ( $result === false ) {
1788                         // a generic "We don't want them to do that"
1789                         $errors[] = array( 'badaccess-group0' );
1790                 }
1791                 return $errors;
1792         }
1793
1794         /**
1795          * Check various permission hooks
1796          *
1797          * @param $action String the action to check
1798          * @param $user User user to check
1799          * @param $errors Array list of current errors
1800          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1801          * @param $short Boolean short circuit on first error
1802          *
1803          * @return Array list of errors
1804          */
1805         private function checkPermissionHooks( $action, $user, $errors, $doExpensiveQueries, $short ) {
1806                 // Use getUserPermissionsErrors instead
1807                 $result = '';
1808                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1809                         return $result ? array() : array( array( 'badaccess-group0' ) );
1810                 }
1811                 // Check getUserPermissionsErrors hook
1812                 if ( !wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1813                         $errors = $this->resultToError( $errors, $result );
1814                 }
1815                 // Check getUserPermissionsErrorsExpensive hook
1816                 if ( $doExpensiveQueries && !( $short && count( $errors ) > 0 ) &&
1817                          !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) ) ) {
1818                         $errors = $this->resultToError( $errors, $result );
1819                 }
1820
1821                 return $errors;
1822         }
1823
1824         /**
1825          * Check permissions on special pages & namespaces
1826          *
1827          * @param $action String the action to check
1828          * @param $user User user to check
1829          * @param $errors Array list of current errors
1830          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1831          * @param $short Boolean short circuit on first error
1832          *
1833          * @return Array list of errors
1834          */
1835         private function checkSpecialsAndNSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1836                 # Only 'createaccount' and 'execute' can be performed on
1837                 # special pages, which don't actually exist in the DB.
1838                 $specialOKActions = array( 'createaccount', 'execute', 'read' );
1839                 if ( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions ) ) {
1840                         $errors[] = array( 'ns-specialprotected' );
1841                 }
1842
1843                 # Check $wgNamespaceProtection for restricted namespaces
1844                 if ( $this->isNamespaceProtected( $user ) ) {
1845                         $ns = $this->mNamespace == NS_MAIN ?
1846                                 wfMessage( 'nstab-main' )->text() : $this->getNsText();
1847                         $errors[] = $this->mNamespace == NS_MEDIAWIKI ?
1848                                 array( 'protectedinterface' ) : array( 'namespaceprotected',  $ns );
1849                 }
1850
1851                 return $errors;
1852         }
1853
1854         /**
1855          * Check CSS/JS sub-page permissions
1856          *
1857          * @param $action String the action to check
1858          * @param $user User user to check
1859          * @param $errors Array list of current errors
1860          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1861          * @param $short Boolean short circuit on first error
1862          *
1863          * @return Array list of errors
1864          */
1865         private function checkCSSandJSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1866                 # Protect css/js subpages of user pages
1867                 # XXX: this might be better using restrictions
1868                 # XXX: right 'editusercssjs' is deprecated, for backward compatibility only
1869                 if ( $action != 'patrol' && !$user->isAllowed( 'editusercssjs' )
1870                                 && !preg_match( '/^' . preg_quote( $user->getName(), '/' ) . '\//', $this->mTextform ) ) {
1871                         if ( $this->isCssSubpage() && !$user->isAllowed( 'editusercss' ) ) {
1872                                 $errors[] = array( 'customcssprotected' );
1873                         } elseif ( $this->isJsSubpage() && !$user->isAllowed( 'edituserjs' ) ) {
1874                                 $errors[] = array( 'customjsprotected' );
1875                         }
1876                 }
1877
1878                 return $errors;
1879         }
1880
1881         /**
1882          * Check against page_restrictions table requirements on this
1883          * page. The user must possess all required rights for this
1884          * action.
1885          *
1886          * @param $action String the action to check
1887          * @param $user User user to check
1888          * @param $errors Array list of current errors
1889          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1890          * @param $short Boolean short circuit on first error
1891          *
1892          * @return Array list of errors
1893          */
1894         private function checkPageRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1895                 foreach ( $this->getRestrictions( $action ) as $right ) {
1896                         // Backwards compatibility, rewrite sysop -> protect
1897                         if ( $right == 'sysop' ) {
1898                                 $right = 'protect';
1899                         }
1900                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1901                                 // Users with 'editprotected' permission can edit protected pages
1902                                 // without cascading option turned on.
1903                                 if ( $action != 'edit' || !$user->isAllowed( 'editprotected' )
1904                                         || $this->mCascadeRestriction )
1905                                 {
1906                                         $errors[] = array( 'protectedpagetext', $right );
1907                                 }
1908                         }
1909                 }
1910
1911                 return $errors;
1912         }
1913
1914         /**
1915          * Check restrictions on cascading pages.
1916          *
1917          * @param $action String the action to check
1918          * @param $user User to check
1919          * @param $errors Array list of current errors
1920          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1921          * @param $short Boolean short circuit on first error
1922          *
1923          * @return Array list of errors
1924          */
1925         private function checkCascadingSourcesRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1926                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1927                         # We /could/ use the protection level on the source page, but it's
1928                         # fairly ugly as we have to establish a precedence hierarchy for pages
1929                         # included by multiple cascade-protected pages. So just restrict
1930                         # it to people with 'protect' permission, as they could remove the
1931                         # protection anyway.
1932                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1933                         # Cascading protection depends on more than this page...
1934                         # Several cascading protected pages may include this page...
1935                         # Check each cascading level
1936                         # This is only for protection restrictions, not for all actions
1937                         if ( isset( $restrictions[$action] ) ) {
1938                                 foreach ( $restrictions[$action] as $right ) {
1939                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1940                                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1941                                                 $pages = '';
1942                                                 foreach ( $cascadingSources as $page )
1943                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1944                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1945                                         }
1946                                 }
1947                         }
1948                 }
1949
1950                 return $errors;
1951         }
1952
1953         /**
1954          * Check action permissions not already checked in checkQuickPermissions
1955          *
1956          * @param $action String the action to check
1957          * @param $user User to check
1958          * @param $errors Array list of current errors
1959          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1960          * @param $short Boolean short circuit on first error
1961          *
1962          * @return Array list of errors
1963          */
1964         private function checkActionPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1965                 global $wgDeleteRevisionsLimit, $wgLang;
1966
1967                 if ( $action == 'protect' ) {
1968                         if ( count( $this->getUserPermissionsErrorsInternal( 'edit', $user, $doExpensiveQueries, true ) ) ) {
1969                                 // If they can't edit, they shouldn't protect.
1970                                 $errors[] = array( 'protect-cantedit' );
1971                         }
1972                 } elseif ( $action == 'create' ) {
1973                         $title_protection = $this->getTitleProtection();
1974                         if( $title_protection ) {
1975                                 if( $title_protection['pt_create_perm'] == 'sysop' ) {
1976                                         $title_protection['pt_create_perm'] = 'protect'; // B/C
1977                                 }
1978                                 if( $title_protection['pt_create_perm'] == '' ||
1979                                         !$user->isAllowed( $title_protection['pt_create_perm'] ) )
1980                                 {
1981                                         $errors[] = array( 'titleprotected', User::whoIs( $title_protection['pt_user'] ), $title_protection['pt_reason'] );
1982                                 }
1983                         }
1984                 } elseif ( $action == 'move' ) {
1985                         // Check for immobile pages
1986                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1987                                 // Specific message for this case
1988                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1989                         } elseif ( !$this->isMovable() ) {
1990                                 // Less specific message for rarer cases
1991                                 $errors[] = array( 'immobile-source-page' );
1992                         }
1993                 } elseif ( $action == 'move-target' ) {
1994                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1995                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1996                         } elseif ( !$this->isMovable() ) {
1997                                 $errors[] = array( 'immobile-target-page' );
1998                         }
1999                 } elseif ( $action == 'delete' ) {
2000                         if ( $doExpensiveQueries && $wgDeleteRevisionsLimit
2001                                 && !$this->userCan( 'bigdelete', $user ) && $this->isBigDeletion() )
2002                         {
2003                                 $errors[] = array( 'delete-toobig', $wgLang->formatNum( $wgDeleteRevisionsLimit ) );
2004                         }
2005                 }
2006                 return $errors;
2007         }
2008
2009         /**
2010          * Check that the user isn't blocked from editting.
2011          *
2012          * @param $action String the action to check
2013          * @param $user User to check
2014          * @param $errors Array list of current errors
2015          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
2016          * @param $short Boolean short circuit on first error
2017          *
2018          * @return Array list of errors
2019          */
2020         private function checkUserBlock( $action, $user, $errors, $doExpensiveQueries, $short ) {
2021                 // Account creation blocks handled at userlogin.
2022                 // Unblocking handled in SpecialUnblock
2023                 if( !$doExpensiveQueries || in_array( $action, array( 'createaccount', 'unblock' ) ) ) {
2024                         return $errors;
2025                 }
2026
2027                 global $wgContLang, $wgLang, $wgEmailConfirmToEdit;
2028
2029                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() ) {
2030                         $errors[] = array( 'confirmedittext' );
2031                 }
2032
2033                 if ( ( $action == 'edit' || $action == 'create' ) && !$user->isBlockedFrom( $this ) ) {
2034                         // Don't block the user from editing their own talk page unless they've been
2035                         // explicitly blocked from that too.
2036                 } elseif( $user->isBlocked() && $user->mBlock->prevents( $action ) !== false ) {
2037                         $block = $user->getBlock();
2038
2039                         // This is from OutputPage::blockedPage
2040                         // Copied at r23888 by werdna
2041
2042                         $id = $user->blockedBy();
2043                         $reason = $user->blockedFor();
2044                         if ( $reason == '' ) {
2045                                 $reason = wfMessage( 'blockednoreason' )->text();
2046                         }
2047                         $ip = $user->getRequest()->getIP();
2048
2049                         if ( is_numeric( $id ) ) {
2050                                 $name = User::whoIs( $id );
2051                         } else {
2052                                 $name = $id;
2053                         }
2054
2055                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
2056                         $blockid = $block->getId();
2057                         $blockExpiry = $block->getExpiry();
2058                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $block->mTimestamp ), true );
2059                         if ( $blockExpiry == 'infinity' ) {
2060                                 $blockExpiry = wfMessage( 'infiniteblock' )->text();
2061                         } else {
2062                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
2063                         }
2064
2065                         $intended = strval( $block->getTarget() );
2066
2067                         $errors[] = array( ( $block->mAuto ? 'autoblockedtext' : 'blockedtext' ), $link, $reason, $ip, $name,
2068                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
2069                 }
2070
2071                 return $errors;
2072         }
2073
2074         /**
2075          * Check that the user is allowed to read this page.
2076          *
2077          * @param $action String the action to check
2078          * @param $user User to check
2079          * @param $errors Array list of current errors
2080          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
2081          * @param $short Boolean short circuit on first error
2082          *
2083          * @return Array list of errors
2084          */
2085         private function checkReadPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
2086                 global $wgWhitelistRead, $wgRevokePermissions;
2087                 static $useShortcut = null;
2088
2089                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
2090                 if ( is_null( $useShortcut ) ) {
2091                         $useShortcut = true;
2092                         if ( !User::groupHasPermission( '*', 'read' ) ) {
2093                                 # Not a public wiki, so no shortcut
2094                                 $useShortcut = false;
2095                         } elseif ( !empty( $wgRevokePermissions ) ) {
2096                                 /**
2097                                  * Iterate through each group with permissions being revoked (key not included since we don't care
2098                                  * what the group name is), then check if the read permission is being revoked. If it is, then
2099                                  * we don't use the shortcut below since the user might not be able to read, even though anon
2100                                  * reading is allowed.
2101                                  */
2102                                 foreach ( $wgRevokePermissions as $perms ) {
2103                                         if ( !empty( $perms['read'] ) ) {
2104                                                 # We might be removing the read right from the user, so no shortcut
2105                                                 $useShortcut = false;
2106                                                 break;
2107                                         }
2108                                 }
2109                         }
2110                 }
2111
2112                 $whitelisted = false;
2113                 if ( $useShortcut ) {
2114                         # Shortcut for public wikis, allows skipping quite a bit of code
2115                         $whitelisted = true;
2116                 } elseif ( $user->isAllowed( 'read' ) ) {
2117                         # If the user is allowed to read pages, he is allowed to read all pages
2118                         $whitelisted = true;
2119                 } elseif ( $this->isSpecial( 'Userlogin' )
2120                         || $this->isSpecial( 'ChangePassword' )
2121                         || $this->isSpecial( 'PasswordReset' )
2122                 ) {
2123                         # Always grant access to the login page.
2124                         # Even anons need to be able to log in.
2125                         $whitelisted = true;
2126                 } elseif ( is_array( $wgWhitelistRead ) && count( $wgWhitelistRead ) ) {
2127                         # Time to check the whitelist
2128                         # Only do these checks is there's something to check against
2129                         $name = $this->getPrefixedText();
2130                         $dbName = $this->getPrefixedDBKey();
2131
2132                         // Check for explicit whitelisting with and without underscores
2133                         if ( in_array( $name, $wgWhitelistRead, true ) || in_array( $dbName, $wgWhitelistRead, true ) ) {
2134                                 $whitelisted = true;
2135                         } elseif ( $this->getNamespace() == NS_MAIN ) {
2136                                 # Old settings might have the title prefixed with
2137                                 # a colon for main-namespace pages
2138                                 if ( in_array( ':' . $name, $wgWhitelistRead ) ) {
2139                                         $whitelisted = true;
2140                                 }
2141                         } elseif ( $this->isSpecialPage() ) {
2142                                 # If it's a special page, ditch the subpage bit and check again
2143                                 $name = $this->getDBkey();
2144                                 list( $name, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $name );
2145                                 if ( $name !== false ) {
2146                                         $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
2147                                         if ( in_array( $pure, $wgWhitelistRead, true ) ) {
2148                                                 $whitelisted = true;
2149                                         }
2150                                 }
2151                         }
2152                 }
2153
2154                 if ( !$whitelisted ) {
2155                         # If the title is not whitelisted, give extensions a chance to do so...
2156                         wfRunHooks( 'TitleReadWhitelist', array( $this, $user, &$whitelisted ) );
2157                         if ( !$whitelisted ) {
2158                                 $errors[] = $this->missingPermissionError( $action, $short );
2159                         }
2160                 }
2161
2162                 return $errors;
2163         }
2164
2165         /**
2166          * Get a description array when the user doesn't have the right to perform
2167          * $action (i.e. when User::isAllowed() returns false)
2168          *
2169          * @param $action String the action to check
2170          * @param $short Boolean short circuit on first error
2171          * @return Array list of errors
2172          */
2173         private function missingPermissionError( $action, $short ) {
2174                 // We avoid expensive display logic for quickUserCan's and such
2175                 if ( $short ) {
2176                         return array( 'badaccess-group0' );
2177                 }
2178
2179                 $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
2180                         User::getGroupsWithPermission( $action ) );
2181
2182                 if ( count( $groups ) ) {
2183                         global $wgLang;
2184                         return array(
2185                                 'badaccess-groups',
2186                                 $wgLang->commaList( $groups ),
2187                                 count( $groups )
2188                         );
2189                 } else {
2190                         return array( 'badaccess-group0' );
2191                 }
2192         }
2193
2194         /**
2195          * Can $user perform $action on this page? This is an internal function,
2196          * which checks ONLY that previously checked by userCan (i.e. it leaves out
2197          * checks on wfReadOnly() and blocks)
2198          *
2199          * @param $action String action that permission needs to be checked for
2200          * @param $user User to check
2201          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary queries.
2202          * @param $short Bool Set this to true to stop after the first permission error.
2203          * @return Array of arrays of the arguments to wfMessage to explain permissions problems.
2204          */
2205         protected function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true, $short = false ) {
2206                 wfProfileIn( __METHOD__ );
2207
2208                 # Read has special handling
2209                 if ( $action == 'read' ) {
2210                         $checks = array(
2211                                 'checkPermissionHooks',
2212                                 'checkReadPermissions',
2213                         );
2214                 } else {
2215                         $checks = array(
2216                                 'checkQuickPermissions',
2217                                 'checkPermissionHooks',
2218                                 'checkSpecialsAndNSPermissions',
2219                                 'checkCSSandJSPermissions',
2220                                 'checkPageRestrictions',
2221                                 'checkCascadingSourcesRestrictions',
2222                                 'checkActionPermissions',
2223                                 'checkUserBlock'
2224                         );
2225                 }
2226
2227                 $errors = array();
2228                 while( count( $checks ) > 0 &&
2229                                 !( $short && count( $errors ) > 0 ) ) {
2230                         $method = array_shift( $checks );
2231                         $errors = $this->$method( $action, $user, $errors, $doExpensiveQueries, $short );
2232                 }
2233
2234                 wfProfileOut( __METHOD__ );
2235                 return $errors;
2236         }
2237
2238         /**
2239          * Protect css subpages of user pages: can $wgUser edit
2240          * this page?
2241          *
2242          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2243          * @return Bool
2244          */
2245         public function userCanEditCssSubpage() {
2246                 global $wgUser;
2247                 wfDeprecated( __METHOD__, '1.19' );
2248                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'editusercss' ) )
2249                         || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2250         }
2251
2252         /**
2253          * Protect js subpages of user pages: can $wgUser edit
2254          * this page?
2255          *
2256          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2257          * @return Bool
2258          */
2259         public function userCanEditJsSubpage() {
2260                 global $wgUser;
2261                 wfDeprecated( __METHOD__, '1.19' );
2262                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'edituserjs' ) )
2263                            || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2264         }
2265
2266         /**
2267          * Get a filtered list of all restriction types supported by this wiki.
2268          * @param bool $exists True to get all restriction types that apply to
2269          * titles that do exist, False for all restriction types that apply to
2270          * titles that do not exist
2271          * @return array
2272          */
2273         public static function getFilteredRestrictionTypes( $exists = true ) {
2274                 global $wgRestrictionTypes;
2275                 $types = $wgRestrictionTypes;
2276                 if ( $exists ) {
2277                         # Remove the create restriction for existing titles
2278                         $types = array_diff( $types, array( 'create' ) );
2279                 } else {
2280                         # Only the create and upload restrictions apply to non-existing titles
2281                         $types = array_intersect( $types, array( 'create', 'upload' ) );
2282                 }
2283                 return $types;
2284         }
2285
2286         /**
2287          * Returns restriction types for the current Title
2288          *
2289          * @return array applicable restriction types
2290          */
2291         public function getRestrictionTypes() {
2292                 if ( $this->isSpecialPage() ) {
2293                         return array();
2294                 }
2295
2296                 $types = self::getFilteredRestrictionTypes( $this->exists() );
2297
2298                 if ( $this->getNamespace() != NS_FILE ) {
2299                         # Remove the upload restriction for non-file titles
2300                         $types = array_diff( $types, array( 'upload' ) );
2301                 }
2302
2303                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
2304
2305                 wfDebug( __METHOD__ . ': applicable restrictions to [[' .
2306                         $this->getPrefixedText() . ']] are {' . implode( ',', $types ) . "}\n" );
2307
2308                 return $types;
2309         }
2310
2311         /**
2312          * Is this title subject to title protection?
2313          * Title protection is the one applied against creation of such title.
2314          *
2315          * @return Mixed An associative array representing any existent title
2316          *   protection, or false if there's none.
2317          */
2318         private function getTitleProtection() {
2319                 // Can't protect pages in special namespaces
2320                 if ( $this->getNamespace() < 0 ) {
2321                         return false;
2322                 }
2323
2324                 // Can't protect pages that exist.
2325                 if ( $this->exists() ) {
2326                         return false;
2327                 }
2328
2329                 if ( !isset( $this->mTitleProtection ) ) {
2330                         $dbr = wfGetDB( DB_SLAVE );
2331                         $res = $dbr->select( 'protected_titles', '*',
2332                                 array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2333                                 __METHOD__ );
2334
2335                         // fetchRow returns false if there are no rows.
2336                         $this->mTitleProtection = $dbr->fetchRow( $res );
2337                 }
2338                 return $this->mTitleProtection;
2339         }
2340
2341         /**
2342          * Update the title protection status
2343          *
2344          * @deprecated in 1.19; will be removed in 1.20. Use WikiPage::doUpdateRestrictions() instead.
2345          * @param $create_perm String Permission required for creation
2346          * @param $reason String Reason for protection
2347          * @param $expiry String Expiry timestamp
2348          * @return boolean true
2349          */
2350         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
2351                 wfDeprecated( __METHOD__, '1.19' );
2352
2353                 global $wgUser;
2354
2355                 $limit = array( 'create' => $create_perm );
2356                 $expiry = array( 'create' => $expiry );
2357
2358                 $page = WikiPage::factory( $this );
2359                 $status = $page->doUpdateRestrictions( $limit, $expiry, false, $reason, $wgUser );
2360
2361                 return $status->isOK();
2362         }
2363
2364         /**
2365          * Remove any title protection due to page existing
2366          */
2367         public function deleteTitleProtection() {
2368                 $dbw = wfGetDB( DB_MASTER );
2369
2370                 $dbw->delete(
2371                         'protected_titles',
2372                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2373                         __METHOD__
2374                 );
2375                 $this->mTitleProtection = false;
2376         }
2377
2378         /**
2379          * Is this page "semi-protected" - the *only* protection is autoconfirm?
2380          *
2381          * @param $action String Action to check (default: edit)
2382          * @return Bool
2383          */
2384         public function isSemiProtected( $action = 'edit' ) {
2385                 if ( $this->exists() ) {
2386                         $restrictions = $this->getRestrictions( $action );
2387                         if ( count( $restrictions ) > 0 ) {
2388                                 foreach ( $restrictions as $restriction ) {
2389                                         if ( strtolower( $restriction ) != 'autoconfirmed' ) {
2390                                                 return false;
2391                                         }
2392                                 }
2393                         } else {
2394                                 # Not protected
2395                                 return false;
2396                         }
2397                         return true;
2398                 } else {
2399                         # If it doesn't exist, it can't be protected
2400                         return false;
2401                 }
2402         }
2403
2404         /**
2405          * Does the title correspond to a protected article?
2406          *
2407          * @param $action String the action the page is protected from,
2408          * by default checks all actions.
2409          * @return Bool
2410          */
2411         public function isProtected( $action = '' ) {
2412                 global $wgRestrictionLevels;
2413
2414                 $restrictionTypes = $this->getRestrictionTypes();
2415
2416                 # Special pages have inherent protection
2417                 if( $this->isSpecialPage() ) {
2418                         return true;
2419                 }
2420
2421                 # Check regular protection levels
2422                 foreach ( $restrictionTypes as $type ) {
2423                         if ( $action == $type || $action == '' ) {
2424                                 $r = $this->getRestrictions( $type );
2425                                 foreach ( $wgRestrictionLevels as $level ) {
2426                                         if ( in_array( $level, $r ) && $level != '' ) {
2427                                                 return true;
2428                                         }
2429                                 }
2430                         }
2431                 }
2432
2433                 return false;
2434         }
2435
2436         /**
2437          * Determines if $user is unable to edit this page because it has been protected
2438          * by $wgNamespaceProtection.
2439          *
2440          * @param $user User object to check permissions
2441          * @return Bool
2442          */
2443         public function isNamespaceProtected( User $user ) {
2444                 global $wgNamespaceProtection;
2445
2446                 if ( isset( $wgNamespaceProtection[$this->mNamespace] ) ) {
2447                         foreach ( (array)$wgNamespaceProtection[$this->mNamespace] as $right ) {
2448                                 if ( $right != '' && !$user->isAllowed( $right ) ) {
2449                                         return true;
2450                                 }
2451                         }
2452                 }
2453                 return false;
2454         }
2455
2456         /**
2457          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
2458          *
2459          * @return Bool If the page is subject to cascading restrictions.
2460          */
2461         public function isCascadeProtected() {
2462                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
2463                 return ( $sources > 0 );
2464         }
2465
2466         /**
2467          * Cascading protection: Get the source of any cascading restrictions on this page.
2468          *
2469          * @param $getPages Bool Whether or not to retrieve the actual pages
2470          *        that the restrictions have come from.
2471          * @return Mixed Array of Title objects of the pages from which cascading restrictions
2472          *     have come, false for none, or true if such restrictions exist, but $getPages
2473          *     was not set.  The restriction array is an array of each type, each of which
2474          *     contains a array of unique groups.
2475          */
2476         public function getCascadeProtectionSources( $getPages = true ) {
2477                 global $wgContLang;
2478                 $pagerestrictions = array();
2479
2480                 if ( isset( $this->mCascadeSources ) && $getPages ) {
2481                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
2482                 } elseif ( isset( $this->mHasCascadingRestrictions ) && !$getPages ) {
2483                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
2484                 }
2485
2486                 wfProfileIn( __METHOD__ );
2487
2488                 $dbr = wfGetDB( DB_SLAVE );
2489
2490                 if ( $this->getNamespace() == NS_FILE ) {
2491                         $tables = array( 'imagelinks', 'page_restrictions' );
2492                         $where_clauses = array(
2493                                 'il_to' => $this->getDBkey(),
2494                                 'il_from=pr_page',
2495                                 'pr_cascade' => 1
2496                         );
2497                 } else {
2498                         $tables = array( 'templatelinks', 'page_restrictions' );
2499                         $where_clauses = array(
2500                                 'tl_namespace' => $this->getNamespace(),
2501                                 'tl_title' => $this->getDBkey(),
2502                                 'tl_from=pr_page',
2503                                 'pr_cascade' => 1
2504                         );
2505                 }
2506
2507                 if ( $getPages ) {
2508                         $cols = array( 'pr_page', 'page_namespace', 'page_title',
2509                                                    'pr_expiry', 'pr_type', 'pr_level' );
2510                         $where_clauses[] = 'page_id=pr_page';
2511                         $tables[] = 'page';
2512                 } else {
2513                         $cols = array( 'pr_expiry' );
2514                 }
2515
2516                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
2517
2518                 $sources = $getPages ? array() : false;
2519                 $now = wfTimestampNow();
2520                 $purgeExpired = false;
2521
2522                 foreach ( $res as $row ) {
2523                         $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2524                         if ( $expiry > $now ) {
2525                                 if ( $getPages ) {
2526                                         $page_id = $row->pr_page;
2527                                         $page_ns = $row->page_namespace;
2528                                         $page_title = $row->page_title;
2529                                         $sources[$page_id] = Title::makeTitle( $page_ns, $page_title );
2530                                         # Add groups needed for each restriction type if its not already there
2531                                         # Make sure this restriction type still exists
2532
2533                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
2534                                                 $pagerestrictions[$row->pr_type] = array();
2535                                         }
2536
2537                                         if ( isset( $pagerestrictions[$row->pr_type] ) &&
2538                                                  !in_array( $row->pr_level, $pagerestrictions[$row->pr_type] ) ) {
2539                                                 $pagerestrictions[$row->pr_type][] = $row->pr_level;
2540                                         }
2541                                 } else {
2542                                         $sources = true;
2543                                 }
2544                         } else {
2545                                 // Trigger lazy purge of expired restrictions from the db
2546                                 $purgeExpired = true;
2547                         }
2548                 }
2549                 if ( $purgeExpired ) {
2550                         Title::purgeExpiredRestrictions();
2551                 }
2552
2553                 if ( $getPages ) {
2554                         $this->mCascadeSources = $sources;
2555                         $this->mCascadingRestrictions = $pagerestrictions;
2556                 } else {
2557                         $this->mHasCascadingRestrictions = $sources;
2558                 }
2559
2560                 wfProfileOut( __METHOD__ );
2561                 return array( $sources, $pagerestrictions );
2562         }
2563
2564         /**
2565          * Accessor/initialisation for mRestrictions
2566          *
2567          * @param $action String action that permission needs to be checked for
2568          * @return Array of Strings the array of groups allowed to edit this article
2569          */
2570         public function getRestrictions( $action ) {
2571                 if ( !$this->mRestrictionsLoaded ) {
2572                         $this->loadRestrictions();
2573                 }
2574                 return isset( $this->mRestrictions[$action] )
2575                                 ? $this->mRestrictions[$action]
2576                                 : array();
2577         }
2578
2579         /**
2580          * Get the expiry time for the restriction against a given action
2581          *
2582          * @param $action
2583          * @return String|Bool 14-char timestamp, or 'infinity' if the page is protected forever
2584          *     or not protected at all, or false if the action is not recognised.
2585          */
2586         public function getRestrictionExpiry( $action ) {
2587                 if ( !$this->mRestrictionsLoaded ) {
2588                         $this->loadRestrictions();
2589                 }
2590                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2591         }
2592
2593         /**
2594          * Returns cascading restrictions for the current article
2595          *
2596          * @return Boolean
2597          */
2598         function areRestrictionsCascading() {
2599                 if ( !$this->mRestrictionsLoaded ) {
2600                         $this->loadRestrictions();
2601                 }
2602
2603                 return $this->mCascadeRestriction;
2604         }
2605
2606         /**
2607          * Loads a string into mRestrictions array
2608          *
2609          * @param $res Resource restrictions as an SQL result.
2610          * @param $oldFashionedRestrictions String comma-separated list of page
2611          *        restrictions from page table (pre 1.10)
2612          */
2613         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
2614                 $rows = array();
2615
2616                 foreach ( $res as $row ) {
2617                         $rows[] = $row;
2618                 }
2619
2620                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
2621         }
2622
2623         /**
2624          * Compiles list of active page restrictions from both page table (pre 1.10)
2625          * and page_restrictions table for this existing page.
2626          * Public for usage by LiquidThreads.
2627          *
2628          * @param $rows array of db result objects
2629          * @param $oldFashionedRestrictions string comma-separated list of page
2630          *        restrictions from page table (pre 1.10)
2631          */
2632         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
2633                 global $wgContLang;
2634                 $dbr = wfGetDB( DB_SLAVE );
2635
2636                 $restrictionTypes = $this->getRestrictionTypes();
2637
2638                 foreach ( $restrictionTypes as $type ) {
2639                         $this->mRestrictions[$type] = array();
2640                         $this->mRestrictionsExpiry[$type] = $wgContLang->formatExpiry( '', TS_MW );
2641                 }
2642
2643                 $this->mCascadeRestriction = false;
2644
2645                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2646
2647                 if ( $oldFashionedRestrictions === null ) {
2648                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2649                                 array( 'page_id' => $this->getArticleID() ), __METHOD__ );
2650                 }
2651
2652                 if ( $oldFashionedRestrictions != '' ) {
2653
2654                         foreach ( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2655                                 $temp = explode( '=', trim( $restrict ) );
2656                                 if ( count( $temp ) == 1 ) {
2657                                         // old old format should be treated as edit/move restriction
2658                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2659                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2660                                 } else {
2661                                         $restriction = trim( $temp[1] );
2662                                         if( $restriction != '' ) { //some old entries are empty
2663                                                 $this->mRestrictions[$temp[0]] = explode( ',', $restriction );
2664                                         }
2665                                 }
2666                         }
2667
2668                         $this->mOldRestrictions = true;
2669
2670                 }
2671
2672                 if ( count( $rows ) ) {
2673                         # Current system - load second to make them override.
2674                         $now = wfTimestampNow();
2675                         $purgeExpired = false;
2676
2677                         # Cycle through all the restrictions.
2678                         foreach ( $rows as $row ) {
2679
2680                                 // Don't take care of restrictions types that aren't allowed
2681                                 if ( !in_array( $row->pr_type, $restrictionTypes ) )
2682                                         continue;
2683
2684                                 // This code should be refactored, now that it's being used more generally,
2685                                 // But I don't really see any harm in leaving it in Block for now -werdna
2686                                 $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2687
2688                                 // Only apply the restrictions if they haven't expired!
2689                                 if ( !$expiry || $expiry > $now ) {
2690                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2691                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2692
2693                                         $this->mCascadeRestriction |= $row->pr_cascade;
2694                                 } else {
2695                                         // Trigger a lazy purge of expired restrictions
2696                                         $purgeExpired = true;
2697                                 }
2698                         }
2699
2700                         if ( $purgeExpired ) {
2701                                 Title::purgeExpiredRestrictions();
2702                         }
2703                 }
2704
2705                 $this->mRestrictionsLoaded = true;
2706         }
2707
2708         /**
2709          * Load restrictions from the page_restrictions table
2710          *
2711          * @param $oldFashionedRestrictions String comma-separated list of page
2712          *        restrictions from page table (pre 1.10)
2713          */
2714         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2715                 global $wgContLang;
2716                 if ( !$this->mRestrictionsLoaded ) {
2717                         if ( $this->exists() ) {
2718                                 $dbr = wfGetDB( DB_SLAVE );
2719
2720                                 $res = $dbr->select(
2721                                         'page_restrictions',
2722                                         '*',
2723                                         array( 'pr_page' => $this->getArticleID() ),
2724                                         __METHOD__
2725                                 );
2726
2727                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2728                         } else {
2729                                 $title_protection = $this->getTitleProtection();
2730
2731                                 if ( $title_protection ) {
2732                                         $now = wfTimestampNow();
2733                                         $expiry = $wgContLang->formatExpiry( $title_protection['pt_expiry'], TS_MW );
2734
2735                                         if ( !$expiry || $expiry > $now ) {
2736                                                 // Apply the restrictions
2737                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2738                                                 $this->mRestrictions['create'] = explode( ',', trim( $title_protection['pt_create_perm'] ) );
2739                                         } else { // Get rid of the old restrictions
2740                                                 Title::purgeExpiredRestrictions();
2741                                                 $this->mTitleProtection = false;
2742                                         }
2743                                 } else {
2744                                         $this->mRestrictionsExpiry['create'] = $wgContLang->formatExpiry( '', TS_MW );
2745                                 }
2746                                 $this->mRestrictionsLoaded = true;
2747                         }
2748                 }
2749         }
2750
2751         /**
2752          * Flush the protection cache in this object and force reload from the database.
2753          * This is used when updating protection from WikiPage::doUpdateRestrictions().
2754          */
2755         public function flushRestrictions() {
2756                 $this->mRestrictionsLoaded = false;
2757                 $this->mTitleProtection = null;
2758         }
2759
2760         /**
2761          * Purge expired restrictions from the page_restrictions table
2762          */
2763         static function purgeExpiredRestrictions() {
2764                 $dbw = wfGetDB( DB_MASTER );
2765                 $dbw->delete(
2766                         'page_restrictions',
2767                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2768                         __METHOD__
2769                 );
2770
2771                 $dbw->delete(
2772                         'protected_titles',
2773                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2774                         __METHOD__
2775                 );
2776         }
2777
2778         /**
2779          * Does this have subpages?  (Warning, usually requires an extra DB query.)
2780          *
2781          * @return Bool
2782          */
2783         public function hasSubpages() {
2784                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
2785                         # Duh
2786                         return false;
2787                 }
2788
2789                 # We dynamically add a member variable for the purpose of this method
2790                 # alone to cache the result.  There's no point in having it hanging
2791                 # around uninitialized in every Title object; therefore we only add it
2792                 # if needed and don't declare it statically.
2793                 if ( isset( $this->mHasSubpages ) ) {
2794                         return $this->mHasSubpages;
2795                 }
2796
2797                 $subpages = $this->getSubpages( 1 );
2798                 if ( $subpages instanceof TitleArray ) {
2799                         return $this->mHasSubpages = (bool)$subpages->count();
2800                 }
2801                 return $this->mHasSubpages = false;
2802         }
2803
2804         /**
2805          * Get all subpages of this page.
2806          *
2807          * @param $limit Int maximum number of subpages to fetch; -1 for no limit
2808          * @return mixed TitleArray, or empty array if this page's namespace
2809          *  doesn't allow subpages
2810          */
2811         public function getSubpages( $limit = -1 ) {
2812                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
2813                         return array();
2814                 }
2815
2816                 $dbr = wfGetDB( DB_SLAVE );
2817                 $conds['page_namespace'] = $this->getNamespace();
2818                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
2819                 $options = array();
2820                 if ( $limit > -1 ) {
2821                         $options['LIMIT'] = $limit;
2822                 }
2823                 return $this->mSubpages = TitleArray::newFromResult(
2824                         $dbr->select( 'page',
2825                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
2826                                 $conds,
2827                                 __METHOD__,
2828                                 $options
2829                         )
2830                 );
2831         }
2832
2833         /**
2834          * Is there a version of this page in the deletion archive?
2835          *
2836          * @return Int the number of archived revisions
2837          */
2838         public function isDeleted() {
2839                 if ( $this->getNamespace() < 0 ) {
2840                         $n = 0;
2841                 } else {
2842                         $dbr = wfGetDB( DB_SLAVE );
2843
2844                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2845                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2846                                 __METHOD__
2847                         );
2848                         if ( $this->getNamespace() == NS_FILE ) {
2849                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2850                                         array( 'fa_name' => $this->getDBkey() ),
2851                                         __METHOD__
2852                                 );
2853                         }
2854                 }
2855                 return (int)$n;
2856         }
2857
2858         /**
2859          * Is there a version of this page in the deletion archive?
2860          *
2861          * @return Boolean
2862          */
2863         public function isDeletedQuick() {
2864                 if ( $this->getNamespace() < 0 ) {
2865                         return false;
2866                 }
2867                 $dbr = wfGetDB( DB_SLAVE );
2868                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2869                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2870                         __METHOD__
2871                 );
2872                 if ( !$deleted && $this->getNamespace() == NS_FILE ) {
2873                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2874                                 array( 'fa_name' => $this->getDBkey() ),
2875                                 __METHOD__
2876                         );
2877                 }
2878                 return $deleted;
2879         }
2880
2881         /**
2882          * Get the article ID for this Title from the link cache,
2883          * adding it if necessary
2884          *
2885          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select
2886          *  for update
2887          * @return Int the ID
2888          */
2889         public function getArticleID( $flags = 0 ) {
2890                 if ( $this->getNamespace() < 0 ) {
2891                         return $this->mArticleID = 0;
2892                 }
2893                 $linkCache = LinkCache::singleton();
2894                 if ( $flags & self::GAID_FOR_UPDATE ) {
2895                         $oldUpdate = $linkCache->forUpdate( true );
2896                         $linkCache->clearLink( $this );
2897                         $this->mArticleID = $linkCache->addLinkObj( $this );
2898                         $linkCache->forUpdate( $oldUpdate );
2899                 } else {
2900                         if ( -1 == $this->mArticleID ) {
2901                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2902                         }
2903                 }
2904                 return $this->mArticleID;
2905         }
2906
2907         /**
2908          * Is this an article that is a redirect page?
2909          * Uses link cache, adding it if necessary
2910          *
2911          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2912          * @return Bool
2913          */
2914         public function isRedirect( $flags = 0 ) {
2915                 if ( !is_null( $this->mRedirect ) ) {
2916                         return $this->mRedirect;
2917                 }
2918                 # Calling getArticleID() loads the field from cache as needed
2919                 if ( !$this->getArticleID( $flags ) ) {
2920                         return $this->mRedirect = false;
2921                 }
2922
2923                 $linkCache = LinkCache::singleton();
2924                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2925                 if ( $cached === null ) {
2926                         // TODO: check the assumption that the cache actually knows about this title
2927                         // and handle this, such as get the title from the database.
2928                         // See https://bugzilla.wikimedia.org/show_bug.cgi?id=37209
2929                 }
2930
2931                 $this->mRedirect = (bool)$cached;
2932
2933                 return $this->mRedirect;
2934         }
2935
2936         /**
2937          * What is the length of this page?
2938          * Uses link cache, adding it if necessary
2939          *
2940          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2941          * @return Int
2942          */
2943         public function getLength( $flags = 0 ) {
2944                 if ( $this->mLength != -1 ) {
2945                         return $this->mLength;
2946                 }
2947                 # Calling getArticleID() loads the field from cache as needed
2948                 if ( !$this->getArticleID( $flags ) ) {
2949                         return $this->mLength = 0;
2950                 }
2951                 $linkCache = LinkCache::singleton();
2952                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'length' );
2953                 if ( $cached === null ) { # check the assumption that the cache actually knows about this title
2954                         # XXX: this does apparently happen, see https://bugzilla.wikimedia.org/show_bug.cgi?id=37209
2955                         #      as a stop gap, perhaps log this, but don't throw an exception?
2956                         throw new MWException( "LinkCache doesn't currently know about this title: " . $this->getPrefixedDBkey() );
2957                 }
2958
2959                 $this->mLength = intval( $cached );
2960
2961                 return $this->mLength;
2962         }
2963
2964         /**
2965          * What is the page_latest field for this page?
2966          *
2967          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2968          * @return Int or 0 if the page doesn't exist
2969          */
2970         public function getLatestRevID( $flags = 0 ) {
2971                 if ( !( $flags & Title::GAID_FOR_UPDATE ) && $this->mLatestID !== false ) {
2972                         return intval( $this->mLatestID );
2973                 }
2974                 # Calling getArticleID() loads the field from cache as needed
2975                 if ( !$this->getArticleID( $flags ) ) {
2976                         return $this->mLatestID = 0;
2977                 }
2978                 $linkCache = LinkCache::singleton();
2979                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'revision' );
2980                 if ( $cached === null ) { # check the assumption that the cache actually knows about this title
2981                         # XXX: this does apparently happen, see https://bugzilla.wikimedia.org/show_bug.cgi?id=37209
2982                         #      as a stop gap, perhaps log this, but don't throw an exception?
2983                         throw new MWException( "LinkCache doesn't currently know about this title: " . $this->getPrefixedDBkey() );
2984                 }
2985
2986                 $this->mLatestID = intval( $cached );
2987
2988                 return $this->mLatestID;
2989         }
2990
2991         /**
2992          * This clears some fields in this object, and clears any associated
2993          * keys in the "bad links" section of the link cache.
2994          *
2995          * - This is called from WikiPage::doEdit() and WikiPage::insertOn() to allow
2996          * loading of the new page_id. It's also called from
2997          * WikiPage::doDeleteArticleReal()
2998          *
2999          * @param $newid Int the new Article ID
3000          */
3001         public function resetArticleID( $newid ) {
3002                 $linkCache = LinkCache::singleton();
3003                 $linkCache->clearLink( $this );
3004
3005                 if ( $newid === false ) {
3006                         $this->mArticleID = -1;
3007                 } else {
3008                         $this->mArticleID = intval( $newid );
3009                 }
3010                 $this->mRestrictionsLoaded = false;
3011                 $this->mRestrictions = array();
3012                 $this->mRedirect = null;
3013                 $this->mLength = -1;
3014                 $this->mLatestID = false;
3015                 $this->mContentModel = false;
3016                 $this->mEstimateRevisions = null;
3017         }
3018
3019         /**
3020          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
3021          *
3022          * @param $text String containing title to capitalize
3023          * @param $ns int namespace index, defaults to NS_MAIN
3024          * @return String containing capitalized title
3025          */
3026         public static function capitalize( $text, $ns = NS_MAIN ) {
3027                 global $wgContLang;
3028
3029                 if ( MWNamespace::isCapitalized( $ns ) ) {
3030                         return $wgContLang->ucfirst( $text );
3031                 } else {
3032                         return $text;
3033                 }
3034         }
3035
3036         /**
3037          * Secure and split - main initialisation function for this object
3038          *
3039          * Assumes that mDbkeyform has been set, and is urldecoded
3040          * and uses underscores, but not otherwise munged.  This function
3041          * removes illegal characters, splits off the interwiki and
3042          * namespace prefixes, sets the other forms, and canonicalizes
3043          * everything.
3044          *
3045          * @return Bool true on success
3046          */
3047         private function secureAndSplit() {
3048                 global $wgContLang, $wgLocalInterwiki;
3049
3050                 # Initialisation
3051                 $this->mInterwiki = $this->mFragment = '';
3052                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
3053
3054                 $dbkey = $this->mDbkeyform;
3055
3056                 # Strip Unicode bidi override characters.
3057                 # Sometimes they slip into cut-n-pasted page titles, where the
3058                 # override chars get included in list displays.
3059                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
3060
3061                 # Clean up whitespace
3062                 # Note: use of the /u option on preg_replace here will cause
3063                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
3064                 # conveniently disabling them.
3065                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
3066                 $dbkey = trim( $dbkey, '_' );
3067
3068                 if ( $dbkey == '' ) {
3069                         return false;
3070                 }
3071
3072                 if ( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
3073                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
3074                         return false;
3075                 }
3076
3077                 $this->mDbkeyform = $dbkey;
3078
3079                 # Initial colon indicates main namespace rather than specified default
3080                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
3081                 if ( ':' == $dbkey[0] ) {
3082                         $this->mNamespace = NS_MAIN;
3083                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
3084                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
3085                 }
3086
3087                 # Namespace or interwiki prefix
3088                 $firstPass = true;
3089                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
3090                 do {
3091                         $m = array();
3092                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
3093                                 $p = $m[1];
3094                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
3095                                         # Ordinary namespace
3096                                         $dbkey = $m[2];
3097                                         $this->mNamespace = $ns;
3098                                         # For Talk:X pages, check if X has a "namespace" prefix
3099                                         if ( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
3100                                                 if ( $wgContLang->getNsIndex( $x[1] ) ) {
3101                                                         # Disallow Talk:File:x type titles...
3102                                                         return false;
3103                                                 } elseif ( Interwiki::isValidInterwiki( $x[1] ) ) {
3104                                                         # Disallow Talk:Interwiki:x type titles...
3105                                                         return false;
3106                                                 }
3107                                         }
3108                                 } elseif ( Interwiki::isValidInterwiki( $p ) ) {
3109                                         if ( !$firstPass ) {
3110                                                 # Can't make a local interwiki link to an interwiki link.
3111                                                 # That's just crazy!
3112                                                 return false;
3113                                         }
3114
3115                                         # Interwiki link
3116                                         $dbkey = $m[2];
3117                                         $this->mInterwiki = $wgContLang->lc( $p );
3118
3119                                         # Redundant interwiki prefix to the local wiki
3120                                         if ( $wgLocalInterwiki !== false
3121                                                 && 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) )
3122                                         {
3123                                                 if ( $dbkey == '' ) {
3124                                                         # Can't have an empty self-link
3125                                                         return false;
3126                                                 }
3127                                                 $this->mInterwiki = '';
3128                                                 $firstPass = false;
3129                                                 # Do another namespace split...
3130                                                 continue;
3131                                         }
3132
3133                                         # If there's an initial colon after the interwiki, that also
3134                                         # resets the default namespace
3135                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
3136                                                 $this->mNamespace = NS_MAIN;
3137                                                 $dbkey = substr( $dbkey, 1 );
3138                                         }
3139                                 }
3140                                 # If there's no recognized interwiki or namespace,
3141                                 # then let the colon expression be part of the title.
3142                         }
3143                         break;
3144                 } while ( true );
3145
3146                 # We already know that some pages won't be in the database!
3147                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
3148                         $this->mArticleID = 0;
3149                 }
3150                 $fragment = strstr( $dbkey, '#' );
3151                 if ( false !== $fragment ) {
3152                         $this->setFragment( $fragment );
3153                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
3154                         # remove whitespace again: prevents "Foo_bar_#"
3155                         # becoming "Foo_bar_"
3156                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
3157                 }
3158
3159                 # Reject illegal characters.
3160                 $rxTc = self::getTitleInvalidRegex();
3161                 if ( preg_match( $rxTc, $dbkey ) ) {
3162                         return false;
3163                 }
3164
3165                 # Pages with "/./" or "/../" appearing in the URLs will often be un-
3166                 # reachable due to the way web browsers deal with 'relative' URLs.
3167                 # Also, they conflict with subpage syntax.  Forbid them explicitly.
3168                 if ( strpos( $dbkey, '.' ) !== false &&
3169                          ( $dbkey === '.' || $dbkey === '..' ||
3170                            strpos( $dbkey, './' ) === 0  ||
3171                            strpos( $dbkey, '../' ) === 0 ||
3172                            strpos( $dbkey, '/./' ) !== false ||
3173                            strpos( $dbkey, '/../' ) !== false  ||
3174                            substr( $dbkey, -2 ) == '/.' ||
3175                            substr( $dbkey, -3 ) == '/..' ) )
3176                 {
3177                         return false;
3178                 }
3179
3180                 # Magic tilde sequences? Nu-uh!
3181                 if ( strpos( $dbkey, '~~~' ) !== false ) {
3182                         return false;
3183                 }
3184
3185                 # Limit the size of titles to 255 bytes. This is typically the size of the
3186                 # underlying database field. We make an exception for special pages, which
3187                 # don't need to be stored in the database, and may edge over 255 bytes due
3188                 # to subpage syntax for long titles, e.g. [[Special:Block/Long name]]
3189                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
3190                   strlen( $dbkey ) > 512 )
3191                 {
3192                         return false;
3193                 }
3194
3195                 # Normally, all wiki links are forced to have an initial capital letter so [[foo]]
3196                 # and [[Foo]] point to the same place.  Don't force it for interwikis, since the
3197                 # other site might be case-sensitive.
3198                 $this->mUserCaseDBKey = $dbkey;
3199                 if ( $this->mInterwiki == '' ) {
3200                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
3201                 }
3202
3203                 # Can't make a link to a namespace alone... "empty" local links can only be
3204                 # self-links with a fragment identifier.
3205                 if ( $dbkey == '' && $this->mInterwiki == '' && $this->mNamespace != NS_MAIN ) {
3206                         return false;
3207                 }
3208
3209                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
3210                 // IP names are not allowed for accounts, and can only be referring to
3211                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
3212                 // there are numerous ways to present the same IP. Having sp:contribs scan
3213                 // them all is silly and having some show the edits and others not is
3214                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
3215                 $dbkey = ( $this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK )
3216                         ? IP::sanitizeIP( $dbkey )
3217                         : $dbkey;
3218
3219                 // Any remaining initial :s are illegal.
3220                 if ( $dbkey !== '' && ':' == $dbkey[0] ) {
3221                         return false;
3222                 }
3223
3224                 # Fill fields
3225                 $this->mDbkeyform = $dbkey;
3226                 $this->mUrlform = wfUrlencode( $dbkey );
3227
3228                 $this->mTextform = str_replace( '_', ' ', $dbkey );
3229
3230                 return true;
3231         }
3232
3233         /**
3234          * Get an array of Title objects linking to this Title
3235          * Also stores the IDs in the link cache.
3236          *
3237          * WARNING: do not use this function on arbitrary user-supplied titles!
3238          * On heavily-used templates it will max out the memory.
3239          *
3240          * @param $options Array: may be FOR UPDATE
3241          * @param $table String: table name
3242          * @param $prefix String: fields prefix
3243          * @return Array of Title objects linking here
3244          */
3245         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3246                 if ( count( $options ) > 0 ) {
3247                         $db = wfGetDB( DB_MASTER );
3248                 } else {
3249                         $db = wfGetDB( DB_SLAVE );
3250                 }
3251
3252                 $res = $db->select(
3253                         array( 'page', $table ),
3254                         self::getSelectFields(),
3255                         array(
3256                                 "{$prefix}_from=page_id",
3257                                 "{$prefix}_namespace" => $this->getNamespace(),
3258                                 "{$prefix}_title"     => $this->getDBkey() ),
3259                         __METHOD__,
3260                         $options
3261                 );
3262
3263                 $retVal = array();
3264                 if ( $res->numRows() ) {
3265                         $linkCache = LinkCache::singleton();
3266                         foreach ( $res as $row ) {
3267                                 $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title );
3268                                 if ( $titleObj ) {
3269                                         $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3270                                         $retVal[] = $titleObj;
3271                                 }
3272                         }
3273                 }
3274                 return $retVal;
3275         }
3276
3277         /**
3278          * Get an array of Title objects using this Title as a template
3279          * Also stores the IDs in the link cache.
3280          *
3281          * WARNING: do not use this function on arbitrary user-supplied titles!
3282          * On heavily-used templates it will max out the memory.
3283          *
3284          * @param $options Array: may be FOR UPDATE
3285          * @return Array of Title the Title objects linking here
3286          */
3287         public function getTemplateLinksTo( $options = array() ) {
3288                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
3289         }
3290
3291         /**
3292          * Get an array of Title objects linked from this Title
3293          * Also stores the IDs in the link cache.
3294          *
3295          * WARNING: do not use this function on arbitrary user-supplied titles!
3296          * On heavily-used templates it will max out the memory.
3297          *
3298          * @param $options Array: may be FOR UPDATE
3299          * @param $table String: table name
3300          * @param $prefix String: fields prefix
3301          * @return Array of Title objects linking here
3302          */
3303         public function getLinksFrom( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3304                 global $wgContentHandlerUseDB;
3305
3306                 $id = $this->getArticleID();
3307
3308                 # If the page doesn't exist; there can't be any link from this page
3309                 if ( !$id ) {
3310                         return array();
3311                 }
3312
3313                 if ( count( $options ) > 0 ) {
3314                         $db = wfGetDB( DB_MASTER );
3315                 } else {
3316                         $db = wfGetDB( DB_SLAVE );
3317                 }
3318
3319                 $namespaceFiled = "{$prefix}_namespace";
3320                 $titleField = "{$prefix}_title";
3321
3322                 $fields = array( $namespaceFiled, $titleField, 'page_id', 'page_len', 'page_is_redirect', 'page_latest' );
3323                 if ( $wgContentHandlerUseDB ) $fields[] = 'page_content_model';
3324
3325                 $res = $db->select(
3326                         array( $table, 'page' ),
3327                         $fields,
3328                         array( "{$prefix}_from" => $id ),
3329                         __METHOD__,
3330                         $options,
3331                         array( 'page' => array( 'LEFT JOIN', array( "page_namespace=$namespaceFiled", "page_title=$titleField" ) ) )
3332                 );
3333
3334                 $retVal = array();
3335                 if ( $res->numRows() ) {
3336                         $linkCache = LinkCache::singleton();
3337                         foreach ( $res as $row ) {
3338                                 $titleObj = Title::makeTitle( $row->$namespaceFiled, $row->$titleField );
3339                                 if ( $titleObj ) {
3340                                         if ( $row->page_id ) {
3341                                                 $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3342                                         } else {
3343                                                 $linkCache->addBadLinkObj( $titleObj );
3344                                         }
3345                                         $retVal[] = $titleObj;
3346                                 }
3347                         }
3348                 }
3349                 return $retVal;
3350         }
3351
3352         /**
3353          * Get an array of Title objects used on this Title as a template
3354          * Also stores the IDs in the link cache.
3355          *
3356          * WARNING: do not use this function on arbitrary user-supplied titles!
3357          * On heavily-used templates it will max out the memory.
3358          *
3359          * @param $options Array: may be FOR UPDATE
3360          * @return Array of Title the Title objects used here
3361          */
3362         public function getTemplateLinksFrom( $options = array() ) {
3363                 return $this->getLinksFrom( $options, 'templatelinks', 'tl' );
3364         }
3365
3366         /**
3367          * Get an array of Title objects referring to non-existent articles linked from this page
3368          *
3369          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
3370          * @return Array of Title the Title objects
3371          */
3372         public function getBrokenLinksFrom() {
3373                 if ( $this->getArticleID() == 0 ) {
3374                         # All links from article ID 0 are false positives
3375                         return array();
3376                 }
3377
3378                 $dbr = wfGetDB( DB_SLAVE );
3379                 $res = $dbr->select(
3380                         array( 'page', 'pagelinks' ),
3381                         array( 'pl_namespace', 'pl_title' ),
3382                         array(
3383                                 'pl_from' => $this->getArticleID(),
3384                                 'page_namespace IS NULL'
3385                         ),
3386                         __METHOD__, array(),
3387                         array(
3388                                 'page' => array(
3389                                         'LEFT JOIN',
3390                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
3391                                 )
3392                         )
3393                 );
3394
3395                 $retVal = array();
3396                 foreach ( $res as $row ) {
3397                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
3398                 }
3399                 return $retVal;
3400         }
3401
3402
3403         /**
3404          * Get a list of URLs to purge from the Squid cache when this
3405          * page changes
3406          *
3407          * @return Array of String the URLs
3408          */
3409         public function getSquidURLs() {
3410                 $urls = array(
3411                         $this->getInternalURL(),
3412                         $this->getInternalURL( 'action=history' )
3413                 );
3414
3415                 $pageLang = $this->getPageLanguage();
3416                 if ( $pageLang->hasVariants() ) {
3417                         $variants = $pageLang->getVariants();
3418                         foreach ( $variants as $vCode ) {
3419                                 $urls[] = $this->getInternalURL( '', $vCode );
3420                         }
3421                 }
3422
3423                 return $urls;
3424         }
3425
3426         /**
3427          * Purge all applicable Squid URLs
3428          */
3429         public function purgeSquid() {
3430                 global $wgUseSquid;
3431                 if ( $wgUseSquid ) {
3432                         $urls = $this->getSquidURLs();
3433                         $u = new SquidUpdate( $urls );
3434                         $u->doUpdate();
3435                 }
3436         }
3437
3438         /**
3439          * Move this page without authentication
3440          *
3441          * @param $nt Title the new page Title
3442          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3443          */
3444         public function moveNoAuth( &$nt ) {
3445                 return $this->moveTo( $nt, false );
3446         }
3447
3448         /**
3449          * Check whether a given move operation would be valid.
3450          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
3451          *
3452          * @param $nt Title the new title
3453          * @param $auth Bool indicates whether $wgUser's permissions
3454          *  should be checked
3455          * @param $reason String is the log summary of the move, used for spam checking
3456          * @return Mixed True on success, getUserPermissionsErrors()-like array on failure
3457          */
3458         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
3459                 global $wgUser, $wgContentHandlerUseDB;
3460
3461                 $errors = array();
3462                 if ( !$nt ) {
3463                         // Normally we'd add this to $errors, but we'll get
3464                         // lots of syntax errors if $nt is not an object
3465                         return array( array( 'badtitletext' ) );
3466                 }
3467                 if ( $this->equals( $nt ) ) {
3468                         $errors[] = array( 'selfmove' );
3469                 }
3470                 if ( !$this->isMovable() ) {
3471                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
3472                 }
3473                 if ( $nt->getInterwiki() != '' ) {
3474                         $errors[] = array( 'immobile-target-namespace-iw' );
3475                 }
3476                 if ( !$nt->isMovable() ) {
3477                         $errors[] = array( 'immobile-target-namespace', $nt->getNsText() );
3478                 }
3479
3480                 $oldid = $this->getArticleID();
3481                 $newid = $nt->getArticleID();
3482
3483                 if ( strlen( $nt->getDBkey() ) < 1 ) {
3484                         $errors[] = array( 'articleexists' );
3485                 }
3486                 if ( ( $this->getDBkey() == '' ) ||
3487                          ( !$oldid ) ||
3488                          ( $nt->getDBkey() == '' ) ) {
3489                         $errors[] = array( 'badarticleerror' );
3490                 }
3491
3492                 // Content model checks
3493                 if ( !$wgContentHandlerUseDB &&
3494                                 $this->getContentModel() !== $nt->getContentModel() ) {
3495                         // can't move a page if that would change the page's content model
3496                         $errors[] = array( 'bad-target-model',
3497                                                         ContentHandler::getLocalizedName( $this->getContentModel() ),
3498                                                         ContentHandler::getLocalizedName( $nt->getContentModel() ) );
3499                 }
3500
3501                 // Image-specific checks
3502                 if ( $this->getNamespace() == NS_FILE ) {
3503                         $errors = array_merge( $errors, $this->validateFileMoveOperation( $nt ) );
3504                 }
3505
3506                 if ( $nt->getNamespace() == NS_FILE && $this->getNamespace() != NS_FILE ) {
3507                         $errors[] = array( 'nonfile-cannot-move-to-file' );
3508                 }
3509
3510                 if ( $auth ) {
3511                         $errors = wfMergeErrorArrays( $errors,
3512                                 $this->getUserPermissionsErrors( 'move', $wgUser ),
3513                                 $this->getUserPermissionsErrors( 'edit', $wgUser ),
3514                                 $nt->getUserPermissionsErrors( 'move-target', $wgUser ),
3515                                 $nt->getUserPermissionsErrors( 'edit', $wgUser ) );
3516                 }
3517
3518                 $match = EditPage::matchSummarySpamRegex( $reason );
3519                 if ( $match !== false ) {
3520                         // This is kind of lame, won't display nice
3521                         $errors[] = array( 'spamprotectiontext' );
3522                 }
3523
3524                 $err = null;
3525                 if ( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
3526                         $errors[] = array( 'hookaborted', $err );
3527                 }
3528
3529                 # The move is allowed only if (1) the target doesn't exist, or
3530                 # (2) the target is a redirect to the source, and has no history
3531                 # (so we can undo bad moves right after they're done).
3532
3533                 if ( 0 != $newid ) { # Target exists; check for validity
3534                         if ( !$this->isValidMoveTarget( $nt ) ) {
3535                                 $errors[] = array( 'articleexists' );
3536                         }
3537                 } else {
3538                         $tp = $nt->getTitleProtection();
3539                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
3540                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
3541                                 $errors[] = array( 'cantmove-titleprotected' );
3542                         }
3543                 }
3544                 if ( empty( $errors ) ) {
3545                         return true;
3546                 }
3547                 return $errors;
3548         }
3549
3550         /**
3551          * Check if the requested move target is a valid file move target
3552          * @param Title $nt Target title
3553          * @return array List of errors
3554          */
3555         protected function validateFileMoveOperation( $nt ) {
3556                 global $wgUser;
3557
3558                 $errors = array();
3559
3560                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is not allowed until below
3561
3562                 $file = wfLocalFile( $this );
3563                 if ( $file->exists() ) {
3564                         if ( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
3565                                 $errors[] = array( 'imageinvalidfilename' );
3566                         }
3567                         if ( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
3568                                 $errors[] = array( 'imagetypemismatch' );
3569                         }
3570                 }
3571
3572                 if ( $nt->getNamespace() != NS_FILE ) {
3573                         $errors[] = array( 'imagenocrossnamespace' );
3574                         // From here we want to do checks on a file object, so if we can't
3575                         // create one, we must return.
3576                         return $errors;
3577                 }
3578
3579                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is allowed below here
3580
3581                 $destFile = wfLocalFile( $nt );
3582                 if ( !$wgUser->isAllowed( 'reupload-shared' ) && !$destFile->exists() && wfFindFile( $nt ) ) {
3583                         $errors[] = array( 'file-exists-sharedrepo' );
3584                 }
3585
3586                 return $errors;
3587         }
3588
3589         /**
3590          * Move a title to a new location
3591          *
3592          * @param $nt Title the new title
3593          * @param $auth Bool indicates whether $wgUser's permissions
3594          *  should be checked
3595          * @param $reason String the reason for the move
3596          * @param $createRedirect Bool Whether to create a redirect from the old title to the new title.
3597          *  Ignored if the user doesn't have the suppressredirect right.
3598          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3599          */
3600         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
3601                 global $wgUser;
3602                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
3603                 if ( is_array( $err ) ) {
3604                         // Auto-block user's IP if the account was "hard" blocked
3605                         $wgUser->spreadAnyEditBlock();
3606                         return $err;
3607                 }
3608                 // Check suppressredirect permission
3609                 if ( $auth && !$wgUser->isAllowed( 'suppressredirect' ) ) {
3610                         $createRedirect = true;
3611                 }
3612
3613                 // If it is a file, move it first.
3614                 // It is done before all other moving stuff is done because it's hard to revert.
3615                 $dbw = wfGetDB( DB_MASTER );
3616                 if ( $this->getNamespace() == NS_FILE ) {
3617                         $file = wfLocalFile( $this );
3618                         if ( $file->exists() ) {
3619                                 $status = $file->move( $nt );
3620                                 if ( !$status->isOk() ) {
3621                                         return $status->getErrorsArray();
3622                                 }
3623                         }
3624                         // Clear RepoGroup process cache
3625                         RepoGroup::singleton()->clearCache( $this );
3626                         RepoGroup::singleton()->clearCache( $nt ); # clear false negative cache
3627                 }
3628
3629                 $dbw->begin( __METHOD__ ); # If $file was a LocalFile, its transaction would have closed our own.
3630                 $pageid = $this->getArticleID( self::GAID_FOR_UPDATE );
3631                 $protected = $this->isProtected();
3632
3633                 // Do the actual move
3634                 $this->moveToInternal( $nt, $reason, $createRedirect );
3635
3636                 // Refresh the sortkey for this row.  Be careful to avoid resetting
3637                 // cl_timestamp, which may disturb time-based lists on some sites.
3638                 $prefixes = $dbw->select(
3639                         'categorylinks',
3640                         array( 'cl_sortkey_prefix', 'cl_to' ),
3641                         array( 'cl_from' => $pageid ),
3642                         __METHOD__
3643                 );
3644                 foreach ( $prefixes as $prefixRow ) {
3645                         $prefix = $prefixRow->cl_sortkey_prefix;
3646                         $catTo = $prefixRow->cl_to;
3647                         $dbw->update( 'categorylinks',
3648                                 array(
3649                                         'cl_sortkey' => Collation::singleton()->getSortKey(
3650                                                 $nt->getCategorySortkey( $prefix ) ),
3651                                         'cl_timestamp=cl_timestamp' ),
3652                                 array(
3653                                         'cl_from' => $pageid,
3654                                         'cl_to' => $catTo ),
3655                                 __METHOD__
3656                         );
3657                 }
3658
3659                 $redirid = $this->getArticleID();
3660
3661                 if ( $protected ) {
3662                         # Protect the redirect title as the title used to be...
3663                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
3664                                 array(
3665                                         'pr_page'    => $redirid,
3666                                         'pr_type'    => 'pr_type',
3667                                         'pr_level'   => 'pr_level',
3668                                         'pr_cascade' => 'pr_cascade',
3669                                         'pr_user'    => 'pr_user',
3670                                         'pr_expiry'  => 'pr_expiry'
3671                                 ),
3672                                 array( 'pr_page' => $pageid ),
3673                                 __METHOD__,
3674                                 array( 'IGNORE' )
3675                         );
3676                         # Update the protection log
3677                         $log = new LogPage( 'protect' );
3678                         $comment = wfMessage(
3679                                 'prot_1movedto2',
3680                                 $this->getPrefixedText(),
3681                                 $nt->getPrefixedText()
3682                         )->inContentLanguage()->text();
3683                         if ( $reason ) {
3684                                 $comment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
3685                         }
3686                         // @todo FIXME: $params?
3687                         $log->addEntry( 'move_prot', $nt, $comment, array( $this->getPrefixedText() ) );
3688                 }
3689
3690                 # Update watchlists
3691                 $oldnamespace = $this->getNamespace() & ~1;
3692                 $newnamespace = $nt->getNamespace() & ~1;
3693                 $oldtitle = $this->getDBkey();
3694                 $newtitle = $nt->getDBkey();
3695
3696                 if ( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
3697                         WatchedItem::duplicateEntries( $this, $nt );
3698                 }
3699
3700                 $dbw->commit( __METHOD__ );
3701
3702                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3703                 return true;
3704         }
3705
3706         /**
3707          * Move page to a title which is either a redirect to the
3708          * source page or nonexistent
3709          *
3710          * @param $nt Title the page to move to, which should be a redirect or nonexistent
3711          * @param $reason String The reason for the move
3712          * @param $createRedirect Bool Whether to leave a redirect at the old title. Does not check
3713          *   if the user has the suppressredirect right
3714          * @throws MWException
3715          */
3716         private function moveToInternal( &$nt, $reason = '', $createRedirect = true ) {
3717                 global $wgUser, $wgContLang;
3718
3719                 if ( $nt->exists() ) {
3720                         $moveOverRedirect = true;
3721                         $logType = 'move_redir';
3722                 } else {
3723                         $moveOverRedirect = false;
3724                         $logType = 'move';
3725                 }
3726
3727                 if ( $createRedirect ) {
3728                         $contentHandler = ContentHandler::getForTitle( $this );
3729                         $redirectContent = $contentHandler->makeRedirectContent( $nt );
3730
3731                         // NOTE: If this page's content model does not support redirects, $redirectContent will be null.
3732                 } else {
3733                         $redirectContent = null;
3734                 }
3735
3736                 $logEntry = new ManualLogEntry( 'move', $logType );
3737                 $logEntry->setPerformer( $wgUser );
3738                 $logEntry->setTarget( $this );
3739                 $logEntry->setComment( $reason );
3740                 $logEntry->setParameters( array(
3741                         '4::target' => $nt->getPrefixedText(),
3742                         '5::noredir' => $redirectContent ? '0': '1',
3743                 ) );
3744
3745                 $formatter = LogFormatter::newFromEntry( $logEntry );
3746                 $formatter->setContext( RequestContext::newExtraneousContext( $this ) );
3747                 $comment = $formatter->getPlainActionText();
3748                 if ( $reason ) {
3749                         $comment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
3750                 }
3751                 # Truncate for whole multibyte characters.
3752                 $comment = $wgContLang->truncate( $comment, 255 );
3753
3754                 $oldid = $this->getArticleID();
3755
3756                 $dbw = wfGetDB( DB_MASTER );
3757
3758                 $newpage = WikiPage::factory( $nt );
3759
3760                 if ( $moveOverRedirect ) {
3761                         $newid = $nt->getArticleID();
3762
3763                         # Delete the old redirect. We don't save it to history since
3764                         # by definition if we've got here it's rather uninteresting.
3765                         # We have to remove it so that the next step doesn't trigger
3766                         # a conflict on the unique namespace+title index...
3767                         $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3768
3769                         $newpage->doDeleteUpdates( $newid );
3770                 }
3771
3772                 # Save a null revision in the page's history notifying of the move
3773                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3774                 if ( !is_object( $nullRevision ) ) {
3775                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3776                 }
3777
3778                 $nullRevision->insertOn( $dbw );
3779
3780                 # Change the name of the target page:
3781                 $dbw->update( 'page',
3782                         /* SET */ array(
3783                                 'page_namespace' => $nt->getNamespace(),
3784                                 'page_title'     => $nt->getDBkey(),
3785                         ),
3786                         /* WHERE */ array( 'page_id' => $oldid ),
3787                         __METHOD__
3788                 );
3789
3790                 $this->resetArticleID( 0 );
3791                 $nt->resetArticleID( $oldid );
3792
3793                 $newpage->updateRevisionOn( $dbw, $nullRevision );
3794
3795                 wfRunHooks( 'NewRevisionFromEditComplete',
3796                         array( $newpage, $nullRevision, $nullRevision->getParentId(), $wgUser ) );
3797
3798                 $newpage->doEditUpdates( $nullRevision, $wgUser, array( 'changed' => false ) );
3799
3800                 if ( !$moveOverRedirect ) {
3801                         WikiPage::onArticleCreate( $nt );
3802                 }
3803
3804                 # Recreate the redirect, this time in the other direction.
3805                 if ( !$redirectContent ) {
3806                         WikiPage::onArticleDelete( $this );
3807                 } else {
3808                         $redirectArticle = WikiPage::factory( $this );
3809                         $newid = $redirectArticle->insertOn( $dbw );
3810                         if ( $newid ) { // sanity
3811                                 $redirectRevision = new Revision( array(
3812                                         'page'    => $newid,
3813                                         'comment' => $comment,
3814                                         'content'    => $redirectContent ) );
3815                                 $redirectRevision->insertOn( $dbw );
3816                                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3817
3818                                 wfRunHooks( 'NewRevisionFromEditComplete',
3819                                         array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3820
3821                                 $redirectArticle->doEditUpdates( $redirectRevision, $wgUser, array( 'created' => true ) );
3822                         }
3823                 }
3824
3825                 # Log the move
3826                 $logid = $logEntry->insert();
3827                 $logEntry->publish( $logid );
3828         }
3829
3830         /**
3831          * Move this page's subpages to be subpages of $nt
3832          *
3833          * @param $nt Title Move target
3834          * @param $auth bool Whether $wgUser's permissions should be checked
3835          * @param $reason string The reason for the move
3836          * @param $createRedirect bool Whether to create redirects from the old subpages to
3837          *     the new ones Ignored if the user doesn't have the 'suppressredirect' right
3838          * @return mixed array with old page titles as keys, and strings (new page titles) or
3839          *     arrays (errors) as values, or an error array with numeric indices if no pages
3840          *     were moved
3841          */
3842         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3843                 global $wgMaximumMovedPages;
3844                 // Check permissions
3845                 if ( !$this->userCan( 'move-subpages' ) ) {
3846                         return array( 'cant-move-subpages' );
3847                 }
3848                 // Do the source and target namespaces support subpages?
3849                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
3850                         return array( 'namespace-nosubpages',
3851                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3852                 }
3853                 if ( !MWNamespace::hasSubpages( $nt->getNamespace() ) ) {
3854                         return array( 'namespace-nosubpages',
3855                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3856                 }
3857
3858                 $subpages = $this->getSubpages( $wgMaximumMovedPages + 1 );
3859                 $retval = array();
3860                 $count = 0;
3861                 foreach ( $subpages as $oldSubpage ) {
3862                         $count++;
3863                         if ( $count > $wgMaximumMovedPages ) {
3864                                 $retval[$oldSubpage->getPrefixedTitle()] =
3865                                                 array( 'movepage-max-pages',
3866                                                         $wgMaximumMovedPages );
3867                                 break;
3868                         }
3869
3870                         // We don't know whether this function was called before
3871                         // or after moving the root page, so check both
3872                         // $this and $nt
3873                         if ( $oldSubpage->getArticleID() == $this->getArticleID() ||
3874                                         $oldSubpage->getArticleID() == $nt->getArticleID() )
3875                         {
3876                                 // When moving a page to a subpage of itself,
3877                                 // don't move it twice
3878                                 continue;
3879                         }
3880                         $newPageName = preg_replace(
3881                                         '#^' . preg_quote( $this->getDBkey(), '#' ) . '#',
3882                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3883                                         $oldSubpage->getDBkey() );
3884                         if ( $oldSubpage->isTalkPage() ) {
3885                                 $newNs = $nt->getTalkPage()->getNamespace();
3886                         } else {
3887                                 $newNs = $nt->getSubjectPage()->getNamespace();
3888                         }
3889                         # Bug 14385: we need makeTitleSafe because the new page names may
3890                         # be longer than 255 characters.
3891                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3892
3893                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3894                         if ( $success === true ) {
3895                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3896                         } else {
3897                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3898                         }
3899                 }
3900                 return $retval;
3901         }
3902
3903         /**
3904          * Checks if this page is just a one-rev redirect.
3905          * Adds lock, so don't use just for light purposes.
3906          *
3907          * @return Bool
3908          */
3909         public function isSingleRevRedirect() {
3910                 global $wgContentHandlerUseDB;
3911
3912                 $dbw = wfGetDB( DB_MASTER );
3913
3914                 # Is it a redirect?
3915                 $fields = array( 'page_is_redirect', 'page_latest', 'page_id' );
3916                 if ( $wgContentHandlerUseDB ) $fields[] = 'page_content_model';
3917
3918                 $row = $dbw->selectRow( 'page',
3919                         $fields,
3920                         $this->pageCond(),
3921                         __METHOD__,
3922                         array( 'FOR UPDATE' )
3923                 );
3924                 # Cache some fields we may want
3925                 $this->mArticleID = $row ? intval( $row->page_id ) : 0;
3926                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3927                 $this->mLatestID = $row ? intval( $row->page_latest ) : false;
3928                 $this->mContentModel = $row && isset( $row->page_content_model ) ? strval( $row->page_content_model ) : false;
3929                 if ( !$this->mRedirect ) {
3930                         return false;
3931                 }
3932                 # Does the article have a history?
3933                 $row = $dbw->selectField( array( 'page', 'revision' ),
3934                         'rev_id',
3935                         array( 'page_namespace' => $this->getNamespace(),
3936                                 'page_title' => $this->getDBkey(),
3937                                 'page_id=rev_page',
3938                                 'page_latest != rev_id'
3939                         ),
3940                         __METHOD__,
3941                         array( 'FOR UPDATE' )
3942                 );
3943                 # Return true if there was no history
3944                 return ( $row === false );
3945         }
3946
3947         /**
3948          * Checks if $this can be moved to a given Title
3949          * - Selects for update, so don't call it unless you mean business
3950          *
3951          * @param $nt Title the new title to check
3952          * @return Bool
3953          */
3954         public function isValidMoveTarget( $nt ) {
3955                 # Is it an existing file?
3956                 if ( $nt->getNamespace() == NS_FILE ) {
3957                         $file = wfLocalFile( $nt );
3958                         if ( $file->exists() ) {
3959                                 wfDebug( __METHOD__ . ": file exists\n" );
3960                                 return false;
3961                         }
3962                 }
3963                 # Is it a redirect with no history?
3964                 if ( !$nt->isSingleRevRedirect() ) {
3965                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3966                         return false;
3967                 }
3968                 # Get the article text
3969                 $rev = Revision::newFromTitle( $nt, false, Revision::READ_LATEST );
3970                 if( !is_object( $rev ) ){
3971                         return false;
3972                 }
3973                 $content = $rev->getContent();
3974                 # Does the redirect point to the source?
3975                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3976                 $redirTitle = $content->getRedirectTarget();
3977
3978                 if ( $redirTitle ) {
3979                         if ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3980                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) {
3981                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3982                                 return false;
3983                         } else {
3984                                 return true;
3985                         }
3986                 } else {
3987                         # Fail safe (not a redirect after all. strange.)
3988                         wfDebug( __METHOD__ . ": failsafe: database sais " . $nt->getPrefixedDBkey() .
3989                                                 " is a redirect, but it doesn't contain a valid redirect.\n" );
3990                         return false;
3991                 }
3992         }
3993
3994         /**
3995          * Get categories to which this Title belongs and return an array of
3996          * categories' names.
3997          *
3998          * @return Array of parents in the form:
3999          *        $parent => $currentarticle
4000          */
4001         public function getParentCategories() {
4002                 global $wgContLang;
4003
4004                 $data = array();
4005
4006                 $titleKey = $this->getArticleID();
4007
4008                 if ( $titleKey === 0 ) {
4009                         return $data;
4010                 }
4011
4012                 $dbr = wfGetDB( DB_SLAVE );
4013
4014                 $res = $dbr->select( 'categorylinks', '*',
4015                         array(
4016                                 'cl_from' => $titleKey,
4017                         ),
4018                         __METHOD__,
4019                         array()
4020                 );
4021
4022                 if ( $dbr->numRows( $res ) > 0 ) {
4023                         foreach ( $res as $row ) {
4024                                 // $data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
4025                                 $data[$wgContLang->getNSText( NS_CATEGORY ) . ':' . $row->cl_to] = $this->getFullText();
4026                         }
4027                 }
4028                 return $data;
4029         }
4030
4031         /**
4032          * Get a tree of parent categories
4033          *
4034          * @param $children Array with the children in the keys, to check for circular refs
4035          * @return Array Tree of parent categories
4036          */
4037         public function getParentCategoryTree( $children = array() ) {
4038                 $stack = array();
4039                 $parents = $this->getParentCategories();
4040
4041                 if ( $parents ) {
4042                         foreach ( $parents as $parent => $current ) {
4043                                 if ( array_key_exists( $parent, $children ) ) {
4044                                         # Circular reference
4045                                         $stack[$parent] = array();
4046                                 } else {
4047                                         $nt = Title::newFromText( $parent );
4048                                         if ( $nt ) {
4049                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array( $parent => 1 ) );
4050                                         }
4051                                 }
4052                         }
4053                 }
4054
4055                 return $stack;
4056         }
4057
4058         /**
4059          * Get an associative array for selecting this title from
4060          * the "page" table
4061          *
4062          * @return Array suitable for the $where parameter of DB::select()
4063          */
4064         public function pageCond() {
4065                 if ( $this->mArticleID > 0 ) {
4066                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
4067                         return array( 'page_id' => $this->mArticleID );
4068                 } else {
4069                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
4070                 }
4071         }
4072
4073         /**
4074          * Get the revision ID of the previous revision
4075          *
4076          * @param $revId Int Revision ID. Get the revision that was before this one.
4077          * @param $flags Int Title::GAID_FOR_UPDATE
4078          * @return Int|Bool Old revision ID, or FALSE if none exists
4079          */
4080         public function getPreviousRevisionID( $revId, $flags = 0 ) {
4081                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4082                 $revId = $db->selectField( 'revision', 'rev_id',
4083                         array(
4084                                 'rev_page' => $this->getArticleID( $flags ),
4085                                 'rev_id < ' . intval( $revId )
4086                         ),
4087                         __METHOD__,
4088                         array( 'ORDER BY' => 'rev_id DESC' )
4089                 );
4090
4091                 if ( $revId === false ) {
4092                         return false;
4093                 } else {
4094                         return intval( $revId );
4095                 }
4096         }
4097
4098         /**
4099          * Get the revision ID of the next revision
4100          *
4101          * @param $revId Int Revision ID. Get the revision that was after this one.
4102          * @param $flags Int Title::GAID_FOR_UPDATE
4103          * @return Int|Bool Next revision ID, or FALSE if none exists
4104          */
4105         public function getNextRevisionID( $revId, $flags = 0 ) {
4106                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4107                 $revId = $db->selectField( 'revision', 'rev_id',
4108                         array(
4109                                 'rev_page' => $this->getArticleID( $flags ),
4110                                 'rev_id > ' . intval( $revId )
4111                         ),
4112                         __METHOD__,
4113                         array( 'ORDER BY' => 'rev_id' )
4114                 );
4115
4116                 if ( $revId === false ) {
4117                         return false;
4118                 } else {
4119                         return intval( $revId );
4120                 }
4121         }
4122
4123         /**
4124          * Get the first revision of the page
4125          *
4126          * @param $flags Int Title::GAID_FOR_UPDATE
4127          * @return Revision|Null if page doesn't exist
4128          */
4129         public function getFirstRevision( $flags = 0 ) {
4130                 $pageId = $this->getArticleID( $flags );
4131                 if ( $pageId ) {
4132                         $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4133                         $row = $db->selectRow( 'revision', Revision::selectFields(),
4134                                 array( 'rev_page' => $pageId ),
4135                                 __METHOD__,
4136                                 array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
4137                         );
4138                         if ( $row ) {
4139                                 return new Revision( $row );
4140                         }
4141                 }
4142                 return null;
4143         }
4144
4145         /**
4146          * Get the oldest revision timestamp of this page
4147          *
4148          * @param $flags Int Title::GAID_FOR_UPDATE
4149          * @return String: MW timestamp
4150          */
4151         public function getEarliestRevTime( $flags = 0 ) {
4152                 $rev = $this->getFirstRevision( $flags );
4153                 return $rev ? $rev->getTimestamp() : null;
4154         }
4155
4156         /**
4157          * Check if this is a new page
4158          *
4159          * @return bool
4160          */
4161         public function isNewPage() {
4162                 $dbr = wfGetDB( DB_SLAVE );
4163                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
4164         }
4165
4166         /**
4167          * Check whether the number of revisions of this page surpasses $wgDeleteRevisionsLimit
4168          *
4169          * @return bool
4170          */
4171         public function isBigDeletion() {
4172                 global $wgDeleteRevisionsLimit;
4173
4174                 if ( !$wgDeleteRevisionsLimit ) {
4175                         return false;
4176                 }
4177
4178                 $revCount = $this->estimateRevisionCount();
4179                 return $revCount > $wgDeleteRevisionsLimit;
4180         }
4181
4182         /**
4183          * Get the  approximate revision count of this page.
4184          *
4185          * @return int
4186          */
4187         public function estimateRevisionCount() {
4188                 if ( !$this->exists() ) {
4189                         return 0;
4190                 }
4191
4192                 if ( $this->mEstimateRevisions === null ) {
4193                         $dbr = wfGetDB( DB_SLAVE );
4194                         $this->mEstimateRevisions = $dbr->estimateRowCount( 'revision', '*',
4195                                 array( 'rev_page' => $this->getArticleID() ), __METHOD__ );
4196                 }
4197
4198                 return $this->mEstimateRevisions;
4199         }
4200
4201         /**
4202          * Get the number of revisions between the given revision.
4203          * Used for diffs and other things that really need it.
4204          *
4205          * @param $old int|Revision Old revision or rev ID (first before range)
4206          * @param $new int|Revision New revision or rev ID (first after range)
4207          * @return Int Number of revisions between these revisions.
4208          */
4209         public function countRevisionsBetween( $old, $new ) {
4210                 if ( !( $old instanceof Revision ) ) {
4211                         $old = Revision::newFromTitle( $this, (int)$old );
4212                 }
4213                 if ( !( $new instanceof Revision ) ) {
4214                         $new = Revision::newFromTitle( $this, (int)$new );
4215                 }
4216                 if ( !$old || !$new ) {
4217                         return 0; // nothing to compare
4218                 }
4219                 $dbr = wfGetDB( DB_SLAVE );
4220                 return (int)$dbr->selectField( 'revision', 'count(*)',
4221                         array(
4222                                 'rev_page' => $this->getArticleID(),
4223                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4224                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4225                         ),
4226                         __METHOD__
4227                 );
4228         }
4229
4230         /**
4231          * Get the number of authors between the given revisions or revision IDs.
4232          * Used for diffs and other things that really need it.
4233          *
4234          * @param $old int|Revision Old revision or rev ID (first before range by default)
4235          * @param $new int|Revision New revision or rev ID (first after range by default)
4236          * @param $limit int Maximum number of authors
4237          * @param $options string|array (Optional): Single option, or an array of options:
4238          *     'include_old' Include $old in the range; $new is excluded.
4239          *     'include_new' Include $new in the range; $old is excluded.
4240          *     'include_both' Include both $old and $new in the range.
4241          *     Unknown option values are ignored.
4242          * @return int Number of revision authors in the range; zero if not both revisions exist
4243          */
4244         public function countAuthorsBetween( $old, $new, $limit, $options = array() ) {
4245                 if ( !( $old instanceof Revision ) ) {
4246                         $old = Revision::newFromTitle( $this, (int)$old );
4247                 }
4248                 if ( !( $new instanceof Revision ) ) {
4249                         $new = Revision::newFromTitle( $this, (int)$new );
4250                 }
4251                 // XXX: what if Revision objects are passed in, but they don't refer to this title?
4252                 // Add $old->getPage() != $new->getPage() || $old->getPage() != $this->getArticleID()
4253                 // in the sanity check below?
4254                 if ( !$old || !$new ) {
4255                         return 0; // nothing to compare
4256                 }
4257                 $old_cmp = '>';
4258                 $new_cmp = '<';
4259                 $options = (array) $options;
4260                 if ( in_array( 'include_old', $options ) ) {
4261                         $old_cmp = '>=';
4262                 }
4263                 if ( in_array( 'include_new', $options ) ) {
4264                         $new_cmp = '<=';
4265                 }
4266                 if ( in_array( 'include_both', $options ) ) {
4267                         $old_cmp = '>=';
4268                         $new_cmp = '<=';
4269                 }
4270                 // No DB query needed if $old and $new are the same or successive revisions:
4271                 if ( $old->getId() === $new->getId() ) {
4272                         return ( $old_cmp === '>' && $new_cmp === '<' ) ? 0 : 1;
4273                 } else if ( $old->getId() === $new->getParentId() ) {
4274                         if ( $old_cmp === '>' || $new_cmp === '<' ) {
4275                                 return ( $old_cmp === '>' && $new_cmp === '<' ) ? 0 : 1;
4276                         }
4277                         return ( $old->getRawUserText() === $new->getRawUserText() ) ? 1 : 2;
4278                 }
4279                 $dbr = wfGetDB( DB_SLAVE );
4280                 $res = $dbr->select( 'revision', 'DISTINCT rev_user_text',
4281                         array(
4282                                 'rev_page' => $this->getArticleID(),
4283                                 "rev_timestamp $old_cmp " . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4284                                 "rev_timestamp $new_cmp " . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4285                         ), __METHOD__,
4286                         array( 'LIMIT' => $limit + 1 ) // add one so caller knows it was truncated
4287                 );
4288                 return (int)$dbr->numRows( $res );
4289         }
4290
4291         /**
4292          * Compare with another title.
4293          *
4294          * @param $title Title
4295          * @return Bool
4296          */
4297         public function equals( Title $title ) {
4298                 // Note: === is necessary for proper matching of number-like titles.
4299                 return $this->getInterwiki() === $title->getInterwiki()
4300                         && $this->getNamespace() == $title->getNamespace()
4301                         && $this->getDBkey() === $title->getDBkey();
4302         }
4303
4304         /**
4305          * Check if this title is a subpage of another title
4306          *
4307          * @param $title Title
4308          * @return Bool
4309          */
4310         public function isSubpageOf( Title $title ) {
4311                 return $this->getInterwiki() === $title->getInterwiki()
4312                         && $this->getNamespace() == $title->getNamespace()
4313                         && strpos( $this->getDBkey(), $title->getDBkey() . '/' ) === 0;
4314         }
4315
4316         /**
4317          * Check if page exists.  For historical reasons, this function simply
4318          * checks for the existence of the title in the page table, and will
4319          * thus return false for interwiki links, special pages and the like.
4320          * If you want to know if a title can be meaningfully viewed, you should
4321          * probably call the isKnown() method instead.
4322          *
4323          * @return Bool
4324          */
4325         public function exists() {
4326                 return $this->getArticleID() != 0;
4327         }
4328
4329         /**
4330          * Should links to this title be shown as potentially viewable (i.e. as
4331          * "bluelinks"), even if there's no record by this title in the page
4332          * table?
4333          *
4334          * This function is semi-deprecated for public use, as well as somewhat
4335          * misleadingly named.  You probably just want to call isKnown(), which
4336          * calls this function internally.
4337          *
4338          * (ISSUE: Most of these checks are cheap, but the file existence check
4339          * can potentially be quite expensive.  Including it here fixes a lot of
4340          * existing code, but we might want to add an optional parameter to skip
4341          * it and any other expensive checks.)
4342          *
4343          * @return Bool
4344          */
4345         public function isAlwaysKnown() {
4346                 $isKnown = null;
4347
4348                 /**
4349                  * Allows overriding default behaviour for determining if a page exists.
4350                  * If $isKnown is kept as null, regular checks happen. If it's
4351                  * a boolean, this value is returned by the isKnown method.
4352                  *
4353                  * @since 1.20
4354                  *
4355                  * @param Title $title
4356                  * @param boolean|null $isKnown
4357                  */
4358                 wfRunHooks( 'TitleIsAlwaysKnown', array( $this, &$isKnown ) );
4359
4360                 if ( !is_null( $isKnown ) ) {
4361                         return $isKnown;
4362                 }
4363
4364                 if ( $this->mInterwiki != '' ) {
4365                         return true;  // any interwiki link might be viewable, for all we know
4366                 }
4367
4368                 switch( $this->mNamespace ) {
4369                         case NS_MEDIA:
4370                         case NS_FILE:
4371                                 // file exists, possibly in a foreign repo
4372                                 return (bool)wfFindFile( $this );
4373                         case NS_SPECIAL:
4374                                 // valid special page
4375                                 return SpecialPageFactory::exists( $this->getDBkey() );
4376                         case NS_MAIN:
4377                                 // selflink, possibly with fragment
4378                                 return $this->mDbkeyform == '';
4379                         case NS_MEDIAWIKI:
4380                                 // known system message
4381                                 return $this->hasSourceText() !== false;
4382                         default:
4383                                 return false;
4384                 }
4385         }
4386
4387         /**
4388          * Does this title refer to a page that can (or might) be meaningfully
4389          * viewed?  In particular, this function may be used to determine if
4390          * links to the title should be rendered as "bluelinks" (as opposed to
4391          * "redlinks" to non-existent pages).
4392          * Adding something else to this function will cause inconsistency
4393          * since LinkHolderArray calls isAlwaysKnown() and does its own
4394          * page existence check.
4395          *
4396          * @return Bool
4397          */
4398         public function isKnown() {
4399                 return $this->isAlwaysKnown() || $this->exists();
4400         }
4401
4402         /**
4403          * Does this page have source text?
4404          *
4405          * @return Boolean
4406          */
4407         public function hasSourceText() {
4408                 if ( $this->exists() ) {
4409                         return true;
4410                 }
4411
4412                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
4413                         // If the page doesn't exist but is a known system message, default
4414                         // message content will be displayed, same for language subpages-
4415                         // Use always content language to avoid loading hundreds of languages
4416                         // to get the link color.
4417                         global $wgContLang;
4418                         list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4419                         $message = wfMessage( $name )->inLanguage( $wgContLang )->useDatabase( false );
4420                         return $message->exists();
4421                 }
4422
4423                 return false;
4424         }
4425
4426         /**
4427          * Get the default message text or false if the message doesn't exist
4428          *
4429          * @return String or false
4430          */
4431         public function getDefaultMessageText() {
4432                 global $wgContLang;
4433
4434                 if ( $this->getNamespace() != NS_MEDIAWIKI ) { // Just in case
4435                         return false;
4436                 }
4437
4438                 list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4439                 $message = wfMessage( $name )->inLanguage( $lang )->useDatabase( false );
4440
4441                 if ( $message->exists() ) {
4442                         return $message->plain();
4443                 } else {
4444                         return false;
4445                 }
4446         }
4447
4448         /**
4449          * Updates page_touched for this page; called from LinksUpdate.php
4450          *
4451          * @return Bool true if the update succeded
4452          */
4453         public function invalidateCache() {
4454                 if ( wfReadOnly() ) {
4455                         return false;
4456                 }
4457                 $dbw = wfGetDB( DB_MASTER );
4458                 $success = $dbw->update(
4459                         'page',
4460                         array( 'page_touched' => $dbw->timestamp() ),
4461                         $this->pageCond(),
4462                         __METHOD__
4463                 );
4464                 HTMLFileCache::clearFileCache( $this );
4465                 return $success;
4466         }
4467
4468         /**
4469          * Update page_touched timestamps and send squid purge messages for
4470          * pages linking to this title. May be sent to the job queue depending
4471          * on the number of links. Typically called on create and delete.
4472          */
4473         public function touchLinks() {
4474                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
4475                 $u->doUpdate();
4476
4477                 if ( $this->getNamespace() == NS_CATEGORY ) {
4478                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
4479                         $u->doUpdate();
4480                 }
4481         }
4482
4483         /**
4484          * Get the last touched timestamp
4485          *
4486          * @param $db DatabaseBase: optional db
4487          * @return String last-touched timestamp
4488          */
4489         public function getTouched( $db = null ) {
4490                 $db = isset( $db ) ? $db : wfGetDB( DB_SLAVE );
4491                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
4492                 return $touched;
4493         }
4494
4495         /**
4496          * Get the timestamp when this page was updated since the user last saw it.
4497          *
4498          * @param $user User
4499          * @return String|Null
4500          */
4501         public function getNotificationTimestamp( $user = null ) {
4502                 global $wgUser, $wgShowUpdatedMarker;
4503                 // Assume current user if none given
4504                 if ( !$user ) {
4505                         $user = $wgUser;
4506                 }
4507                 // Check cache first
4508                 $uid = $user->getId();
4509                 // avoid isset here, as it'll return false for null entries
4510                 if ( array_key_exists( $uid, $this->mNotificationTimestamp ) ) {
4511                         return $this->mNotificationTimestamp[$uid];
4512                 }
4513                 if ( !$uid || !$wgShowUpdatedMarker ) {
4514                         return $this->mNotificationTimestamp[$uid] = false;
4515                 }
4516                 // Don't cache too much!
4517                 if ( count( $this->mNotificationTimestamp ) >= self::CACHE_MAX ) {
4518                         $this->mNotificationTimestamp = array();
4519                 }
4520                 $dbr = wfGetDB( DB_SLAVE );
4521                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
4522                         'wl_notificationtimestamp',
4523                         array(
4524                                 'wl_user' => $user->getId(),
4525                                 'wl_namespace' => $this->getNamespace(),
4526                                 'wl_title' => $this->getDBkey(),
4527                         ),
4528                         __METHOD__
4529                 );
4530                 return $this->mNotificationTimestamp[$uid];
4531         }
4532
4533         /**
4534          * Generate strings used for xml 'id' names in monobook tabs
4535          *
4536          * @param $prepend string defaults to 'nstab-'
4537          * @return String XML 'id' name
4538          */
4539         public function getNamespaceKey( $prepend = 'nstab-' ) {
4540                 global $wgContLang;
4541                 // Gets the subject namespace if this title
4542                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
4543                 // Checks if cononical namespace name exists for namespace
4544                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
4545                         // Uses canonical namespace name
4546                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
4547                 } else {
4548                         // Uses text of namespace
4549                         $namespaceKey = $this->getSubjectNsText();
4550                 }
4551                 // Makes namespace key lowercase
4552                 $namespaceKey = $wgContLang->lc( $namespaceKey );
4553                 // Uses main
4554                 if ( $namespaceKey == '' ) {
4555                         $namespaceKey = 'main';
4556                 }
4557                 // Changes file to image for backwards compatibility
4558                 if ( $namespaceKey == 'file' ) {
4559                         $namespaceKey = 'image';
4560                 }
4561                 return $prepend . $namespaceKey;
4562         }
4563
4564         /**
4565          * Get all extant redirects to this Title
4566          *
4567          * @param $ns Int|Null Single namespace to consider; NULL to consider all namespaces
4568          * @return Array of Title redirects to this title
4569          */
4570         public function getRedirectsHere( $ns = null ) {
4571                 $redirs = array();
4572
4573                 $dbr = wfGetDB( DB_SLAVE );
4574                 $where = array(
4575                         'rd_namespace' => $this->getNamespace(),
4576                         'rd_title' => $this->getDBkey(),
4577                         'rd_from = page_id'
4578                 );
4579                 if ( $this->isExternal() ) {
4580                         $where['rd_interwiki'] = $this->getInterwiki();
4581                 } else {
4582                         $where[] = 'rd_interwiki = ' . $dbr->addQuotes( '' ) . ' OR rd_interwiki IS NULL';
4583                 }
4584                 if ( !is_null( $ns ) ) {
4585                         $where['page_namespace'] = $ns;
4586                 }
4587
4588                 $res = $dbr->select(
4589                         array( 'redirect', 'page' ),
4590                         array( 'page_namespace', 'page_title' ),
4591                         $where,
4592                         __METHOD__
4593                 );
4594
4595                 foreach ( $res as $row ) {
4596                         $redirs[] = self::newFromRow( $row );
4597                 }
4598                 return $redirs;
4599         }
4600
4601         /**
4602          * Check if this Title is a valid redirect target
4603          *
4604          * @return Bool
4605          */
4606         public function isValidRedirectTarget() {
4607                 global $wgInvalidRedirectTargets;
4608
4609                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
4610                 if ( $this->isSpecial( 'Userlogout' ) ) {
4611                         return false;
4612                 }
4613
4614                 foreach ( $wgInvalidRedirectTargets as $target ) {
4615                         if ( $this->isSpecial( $target ) ) {
4616                                 return false;
4617                         }
4618                 }
4619
4620                 return true;
4621         }
4622
4623         /**
4624          * Get a backlink cache object
4625          *
4626          * @return BacklinkCache
4627          */
4628         public function getBacklinkCache() {
4629                 return BacklinkCache::get( $this );
4630         }
4631
4632         /**
4633          * Whether the magic words __INDEX__ and __NOINDEX__ function for  this page.
4634          *
4635          * @return Boolean
4636          */
4637         public function canUseNoindex() {
4638                 global $wgContentNamespaces, $wgExemptFromUserRobotsControl;
4639
4640                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
4641                         ? $wgContentNamespaces
4642                         : $wgExemptFromUserRobotsControl;
4643
4644                 return !in_array( $this->mNamespace, $bannedNamespaces );
4645
4646         }
4647
4648         /**
4649          * Returns the raw sort key to be used for categories, with the specified
4650          * prefix.  This will be fed to Collation::getSortKey() to get a
4651          * binary sortkey that can be used for actual sorting.
4652          *
4653          * @param $prefix string The prefix to be used, specified using
4654          *   {{defaultsort:}} or like [[Category:Foo|prefix]].  Empty for no
4655          *   prefix.
4656          * @return string
4657          */
4658         public function getCategorySortkey( $prefix = '' ) {
4659                 $unprefixed = $this->getText();
4660
4661                 // Anything that uses this hook should only depend
4662                 // on the Title object passed in, and should probably
4663                 // tell the users to run updateCollations.php --force
4664                 // in order to re-sort existing category relations.
4665                 wfRunHooks( 'GetDefaultSortkey', array( $this, &$unprefixed ) );
4666                 if ( $prefix !== '' ) {
4667                         # Separate with a line feed, so the unprefixed part is only used as
4668                         # a tiebreaker when two pages have the exact same prefix.
4669                         # In UCA, tab is the only character that can sort above LF
4670                         # so we strip both of them from the original prefix.
4671                         $prefix = strtr( $prefix, "\n\t", '  ' );
4672                         return "$prefix\n$unprefixed";
4673                 }
4674                 return $unprefixed;
4675         }
4676
4677         /**
4678          * Get the language in which the content of this page is written in
4679          * wikitext. Defaults to $wgContLang, but in certain cases it can be
4680          * e.g. $wgLang (such as special pages, which are in the user language).
4681          *
4682          * @since 1.18
4683          * @return Language
4684          */
4685         public function getPageLanguage() {
4686                 global $wgLang;
4687                 if ( $this->isSpecialPage() ) {
4688                         // special pages are in the user language
4689                         return $wgLang;
4690                 }
4691
4692                 //TODO: use the LinkCache to cache this! Note that this may depend on user settings, so the cache should be only per-request.
4693                 //NOTE: ContentHandler::getPageLanguage() may need to load the content to determine the page language!
4694                 $contentHandler = ContentHandler::getForTitle( $this );
4695                 $pageLang = $contentHandler->getPageLanguage( $this );
4696
4697                 // Hook at the end because we don't want to override the above stuff
4698                 wfRunHooks( 'PageContentLanguage', array( $this, &$pageLang, $wgLang ) );
4699                 return wfGetLangObj( $pageLang );
4700         }
4701
4702         /**
4703          * Get the language in which the content of this page is written when
4704          * viewed by user. Defaults to $wgContLang, but in certain cases it can be
4705          * e.g. $wgLang (such as special pages, which are in the user language).
4706          *
4707          * @since 1.20
4708          * @return Language
4709          */
4710         public function getPageViewLanguage() {
4711                 global $wgLang;
4712
4713                 if ( $this->isSpecialPage() ) {
4714                         // If the user chooses a variant, the content is actually
4715                         // in a language whose code is the variant code.
4716                         $variant = $wgLang->getPreferredVariant();
4717                         if ( $wgLang->getCode() !== $variant ) {
4718                                 return Language::factory( $variant );
4719                         }
4720
4721                         return $wgLang;
4722                 }
4723
4724                 //NOTE: can't be cached persistently, depends on user settings
4725                 //NOTE: ContentHandler::getPageViewLanguage() may need to load the content to determine the page language!
4726                 $contentHandler = ContentHandler::getForTitle( $this );
4727                 $pageLang = $contentHandler->getPageViewLanguage( $this );
4728                 return $pageLang;
4729         }
4730 }