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 $this->mNamespace;
 673         }
 674
 675         /**
 676          * Get the page's content model id, see the CONTENT_MODEL_XXX constants.
 677          *
 678          * @throws MWException
 679          * @return String: Content model id
 680          */
 681         public function getContentModel() {
 682                 if ( !$this->mContentModel ) {
 683                         $linkCache = LinkCache::singleton();
 684                         $linkCache->addLinkObj( $this );
 685                         $this->mContentModel = $linkCache->getGoodLinkFieldObj( $this, 'model' );
 686                 }
 687
 688                 if ( !$this->mContentModel ) {
 689                         $this->mContentModel = ContentHandler::getDefaultModelFor( $this );
 690                 }
 691
 692                 if( !$this->mContentModel ) {
 693                         throw new MWException( 'Failed to determine content model!' );
 694                 }
 695
 696                 return $this->mContentModel;
 697         }
 698
 699         /**
 700          * Convenience method for checking a title's content model name
 701          *
 702          * @param String $id The content model ID (use the CONTENT_MODEL_XXX constants).
 703          * @return Boolean true if $this->getContentModel() == $id
 704          */
 705         public function hasContentModel( $id ) {
 706                 return $this->getContentModel() == $id;
 707         }
 708
 709         /**
 710          * Get the namespace text
 711          *
 712          * @return String: Namespace text
 713          */
 714         public function getNsText() {
 715                 global $wgContLang;
 716
 717                 if ( $this->mInterwiki != '' ) {
 718                         // This probably shouldn't even happen. ohh man, oh yuck.
 719                         // But for interwiki transclusion it sometimes does.
 720                         // Shit. Shit shit shit.
 721                         //
 722                         // Use the canonical namespaces if possible to try to
 723                         // resolve a foreign namespace.
 724                         if ( MWNamespace::exists( $this->mNamespace ) ) {
 725                                 return MWNamespace::getCanonicalName( $this->mNamespace );
 726                         }
 727                 }
 728
 729                 if ( $wgContLang->needsGenderDistinction() &&
 730                                 MWNamespace::hasGenderDistinction( $this->mNamespace ) ) {
 731                         $gender = GenderCache::singleton()->getGenderOf( $this->getText(), __METHOD__ );
 732                         return $wgContLang->getGenderNsText( $this->mNamespace, $gender );
 733                 }
 734
 735                 return $wgContLang->getNsText( $this->mNamespace );
 736         }
 737
 738         /**
 739          * Get the namespace text of the subject (rather than talk) page
 740          *
 741          * @return String Namespace text
 742          */
 743         public function getSubjectNsText() {
 744                 global $wgContLang;
 745                 return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
 746         }
 747
 748         /**
 749          * Get the namespace text of the talk page
 750          *
 751          * @return String Namespace text
 752          */
 753         public function getTalkNsText() {
 754                 global $wgContLang;
 755                 return( $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) ) );
 756         }
 757
 758         /**
 759          * Could this title have a corresponding talk page?
 760          *
 761          * @return Bool TRUE or FALSE
 762          */
 763         public function canTalk() {
 764                 return( MWNamespace::canTalk( $this->mNamespace ) );
 765         }
 766
 767         /**
 768          * Is this in a namespace that allows actual pages?
 769          *
 770          * @return Bool
 771          * @internal note -- uses hardcoded namespace index instead of constants
 772          */
 773         public function canExist() {
 774                 return $this->mNamespace >= NS_MAIN;
 775         }
 776
 777         /**
 778          * Can this title be added to a user's watchlist?
 779          *
 780          * @return Bool TRUE or FALSE
 781          */
 782         public function isWatchable() {
 783                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
 784         }
 785
 786         /**
 787          * Returns true if this is a special page.
 788          *
 789          * @return boolean
 790          */
 791         public function isSpecialPage() {
 792                 return $this->getNamespace() == NS_SPECIAL;
 793         }
 794
 795         /**
 796          * Returns true if this title resolves to the named special page
 797          *
 798          * @param $name String The special page name
 799          * @return boolean
 800          */
 801         public function isSpecial( $name ) {
 802                 if ( $this->isSpecialPage() ) {
 803                         list( $thisName, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $this->getDBkey() );
 804                         if ( $name == $thisName ) {
 805                                 return true;
 806                         }
 807                 }
 808                 return false;
 809         }
 810
 811         /**
 812          * If the Title refers to a special page alias which is not the local default, resolve
 813          * the alias, and localise the name as necessary.  Otherwise, return $this
 814          *
 815          * @return Title
 816          */
 817         public function fixSpecialName() {
 818                 if ( $this->isSpecialPage() ) {
 819                         list( $canonicalName, $par ) = SpecialPageFactory::resolveAlias( $this->mDbkeyform );
 820                         if ( $canonicalName ) {
 821                                 $localName = SpecialPageFactory::getLocalNameFor( $canonicalName, $par );
 822                                 if ( $localName != $this->mDbkeyform ) {
 823                                         return Title::makeTitle( NS_SPECIAL, $localName );
 824                                 }
 825                         }
 826                 }
 827                 return $this;
 828         }
 829
 830         /**
 831          * Returns true if the title is inside the specified namespace.
 832          *
 833          * Please make use of this instead of comparing to getNamespace()
 834          * This function is much more resistant to changes we may make
 835          * to namespaces than code that makes direct comparisons.
 836          * @param $ns int The namespace
 837          * @return bool
 838          * @since 1.19
 839          */
 840         public function inNamespace( $ns ) {
 841                 return MWNamespace::equals( $this->getNamespace(), $ns );
 842         }
 843
 844         /**
 845          * Returns true if the title is inside one of the specified namespaces.
 846          *
 847          * @param ...$namespaces The namespaces to check for
 848          * @return bool
 849          * @since 1.19
 850          */
 851         public function inNamespaces( /* ... */ ) {
 852                 $namespaces = func_get_args();
 853                 if ( count( $namespaces ) > 0 && is_array( $namespaces[0] ) ) {
 854                         $namespaces = $namespaces[0];
 855                 }
 856
 857                 foreach ( $namespaces as $ns ) {
 858                         if ( $this->inNamespace( $ns ) ) {
 859                                 return true;
 860                         }
 861                 }
 862
 863                 return false;
 864         }
 865
 866         /**
 867          * Returns true if the title has the same subject namespace as the
 868          * namespace specified.
 869          * For example this method will take NS_USER and return true if namespace
 870          * is either NS_USER or NS_USER_TALK since both of them have NS_USER
 871          * as their subject namespace.
 872          *
 873          * This is MUCH simpler than individually testing for equivilance
 874          * against both NS_USER and NS_USER_TALK, and is also forward compatible.
 875          * @since 1.19
 876          * @param $ns int
 877          * @return bool
 878          */
 879         public function hasSubjectNamespace( $ns ) {
 880                 return MWNamespace::subjectEquals( $this->getNamespace(), $ns );
 881         }
 882
 883         /**
 884          * Is this Title in a namespace which contains content?
 885          * In other words, is this a content page, for the purposes of calculating
 886          * statistics, etc?
 887          *
 888          * @return Boolean
 889          */
 890         public function isContentPage() {
 891                 return MWNamespace::isContent( $this->getNamespace() );
 892         }
 893
 894         /**
 895          * Would anybody with sufficient privileges be able to move this page?
 896          * Some pages just aren't movable.
 897          *
 898          * @return Bool TRUE or FALSE
 899          */
 900         public function isMovable() {
 901                 if ( !MWNamespace::isMovable( $this->getNamespace() ) || $this->getInterwiki() != '' ) {
 902                         // Interwiki title or immovable namespace. Hooks don't get to override here
 903                         return false;
 904                 }
 905
 906                 $result = true;
 907                 wfRunHooks( 'TitleIsMovable', array( $this, &$result ) );
 908                 return $result;
 909         }
 910
 911         /**
 912          * Is this the mainpage?
 913          * @note Title::newFromText seems to be sufficiently optimized by the title
 914          * cache that we don't need to over-optimize by doing direct comparisons and
 915          * acidentally creating new bugs where $title->equals( Title::newFromText() )
 916          * ends up reporting something differently than $title->isMainPage();
 917          *
 918          * @since 1.18
 919          * @return Bool
 920          */
 921         public function isMainPage() {
 922                 return $this->equals( Title::newMainPage() );
 923         }
 924
 925         /**
 926          * Is this a subpage?
 927          *
 928          * @return Bool
 929          */
 930         public function isSubpage() {
 931                 return MWNamespace::hasSubpages( $this->mNamespace )
 932                         ? strpos( $this->getText(), '/' ) !== false
 933                         : false;
 934         }
 935
 936         /**
 937          * Is this a conversion table for the LanguageConverter?
 938          *
 939          * @return Bool
 940          */
 941         public function isConversionTable() {
 942                 //@todo: ConversionTable should become a separate content model.
 943
 944                 return $this->getNamespace() == NS_MEDIAWIKI &&
 945                         strpos( $this->getText(), 'Conversiontable/' ) === 0;
 946         }
 947
 948         /**
 949          * Does that page contain wikitext, or it is JS, CSS or whatever?
 950          *
 951          * @return Bool
 952          */
 953         public function isWikitextPage() {
 954                 return $this->hasContentModel( CONTENT_MODEL_WIKITEXT );
 955         }
 956
 957         /**
 958          * Could this page contain custom CSS or JavaScript for the global UI.
 959          * This is generally true for pages in the MediaWiki namespace having CONTENT_MODEL_CSS
 960          * or CONTENT_MODEL_JAVASCRIPT.
 961          *
 962          * This method does *not* return true for per-user JS/CSS. Use isCssJsSubpage() for that!
 963          *
 964          * Note that this method should not return true for pages that contain and show "inactive" CSS or JS.
 965          *
 966          * @return Bool
 967          */
 968         public function isCssOrJsPage() {
 969                 $isCssOrJsPage = NS_MEDIAWIKI == $this->mNamespace
 970                         && ( $this->hasContentModel( CONTENT_MODEL_CSS )
 971                                 || $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
 972
 973                 #NOTE: this hook is also called in ContentHandler::getDefaultModel. It's called here again to make sure
 974                 #      hook funktions can force this method to return true even outside the mediawiki namespace.
 975
 976                 wfRunHooks( 'TitleIsCssOrJsPage', array( $this, &$isCssOrJsPage ) );
 977
 978                 return $isCssOrJsPage;
 979         }
 980
 981         /**
 982          * Is this a .css or .js subpage of a user page?
 983          * @return Bool
 984          */
 985         public function isCssJsSubpage() {
 986                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
 987                                 && ( $this->hasContentModel( CONTENT_MODEL_CSS )
 988                                         || $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) ) );
 989         }
 990
 991         /**
 992          * Trim down a .css or .js subpage title to get the corresponding skin name
 993          *
 994          * @return string containing skin name from .css or .js subpage title
 995          */
 996         public function getSkinFromCssJsSubpage() {
 997                 $subpage = explode( '/', $this->mTextform );
 998                 $subpage = $subpage[ count( $subpage ) - 1 ];
 999                 $lastdot = strrpos( $subpage, '.' );
1000                 if ( $lastdot === false )
1001                         return $subpage; # Never happens: only called for names ending in '.css' or '.js'
1002                 return substr( $subpage, 0, $lastdot );
1003         }
1004
1005         /**
1006          * Is this a .css subpage of a user page?
1007          *
1008          * @return Bool
1009          */
1010         public function isCssSubpage() {
1011                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
1012                         && $this->hasContentModel( CONTENT_MODEL_CSS ) );
1013         }
1014
1015         /**
1016          * Is this a .js subpage of a user page?
1017          *
1018          * @return Bool
1019          */
1020         public function isJsSubpage() {
1021                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
1022                         && $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
1023         }
1024
1025         /**
1026          * Is this a talk page of some sort?
1027          *
1028          * @return Bool
1029          */
1030         public function isTalkPage() {
1031                 return MWNamespace::isTalk( $this->getNamespace() );
1032         }
1033
1034         /**
1035          * Get a Title object associated with the talk page of this article
1036          *
1037          * @return Title the object for the talk page
1038          */
1039         public function getTalkPage() {
1040                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1041         }
1042
1043         /**
1044          * Get a title object associated with the subject page of this
1045          * talk page
1046          *
1047          * @return Title the object for the subject page
1048          */
1049         public function getSubjectPage() {
1050                 // Is this the same title?
1051                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
1052                 if ( $this->getNamespace() == $subjectNS ) {
1053                         return $this;
1054                 }
1055                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
1056         }
1057
1058         /**
1059          * Get the default namespace index, for when there is no namespace
1060          *
1061          * @return Int Default namespace index
1062          */
1063         public function getDefaultNamespace() {
1064                 return $this->mDefaultNamespace;
1065         }
1066
1067         /**
1068          * Get title for search index
1069          *
1070          * @return String a stripped-down title string ready for the
1071          *  search index
1072          */
1073         public function getIndexTitle() {
1074                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
1075         }
1076
1077         /**
1078          * Get the Title fragment (i.e.\ the bit after the #) in text form
1079          *
1080          * @return String Title fragment
1081          */
1082         public function getFragment() {
1083                 return $this->mFragment;
1084         }
1085
1086         /**
1087          * Get the fragment in URL form, including the "#" character if there is one
1088          * @return String Fragment in URL form
1089          */
1090         public function getFragmentForURL() {
1091                 if ( $this->mFragment == '' ) {
1092                         return '';
1093                 } else {
1094                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
1095                 }
1096         }
1097
1098         /**
1099          * Set the fragment for this title. Removes the first character from the
1100          * specified fragment before setting, so it assumes you're passing it with
1101          * an initial "#".
1102          *
1103          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
1104          * Still in active use privately.
1105          *
1106          * @param $fragment String text
1107          */
1108         public function setFragment( $fragment ) {
1109                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
1110         }
1111
1112         /**
1113          * Prefix some arbitrary text with the namespace or interwiki prefix
1114          * of this object
1115          *
1116          * @param $name String the text
1117          * @return String the prefixed text
1118          * @private
1119          */
1120         private function prefix( $name ) {
1121                 $p = '';
1122                 if ( $this->mInterwiki != '' ) {
1123                         $p = $this->mInterwiki . ':';
1124                 }
1125
1126                 if ( 0 != $this->mNamespace ) {
1127                         $p .= $this->getNsText() . ':';
1128                 }
1129                 return $p . $name;
1130         }
1131
1132         /**
1133          * Get the prefixed database key form
1134          *
1135          * @return String the prefixed title, with underscores and
1136          *  any interwiki and namespace prefixes
1137          */
1138         public function getPrefixedDBkey() {
1139                 $s = $this->prefix( $this->mDbkeyform );
1140                 $s = str_replace( ' ', '_', $s );
1141                 return $s;
1142         }
1143
1144         /**
1145          * Get the prefixed title with spaces.
1146          * This is the form usually used for display
1147          *
1148          * @return String the prefixed title, with spaces
1149          */
1150         public function getPrefixedText() {
1151                 // @todo FIXME: Bad usage of empty() ?
1152                 if ( empty( $this->mPrefixedText ) ) {
1153                         $s = $this->prefix( $this->mTextform );
1154                         $s = str_replace( '_', ' ', $s );
1155                         $this->mPrefixedText = $s;
1156                 }
1157                 return $this->mPrefixedText;
1158         }
1159
1160         /**
1161          * Return a string representation of this title
1162          *
1163          * @return String representation of this title
1164          */
1165         public function __toString() {
1166                 return $this->getPrefixedText();
1167         }
1168
1169         /**
1170          * Get the prefixed title with spaces, plus any fragment
1171          * (part beginning with '#')
1172          *
1173          * @return String the prefixed title, with spaces and the fragment, including '#'
1174          */
1175         public function getFullText() {
1176                 $text = $this->getPrefixedText();
1177                 if ( $this->mFragment != '' ) {
1178                         $text .= '#' . $this->mFragment;
1179                 }
1180                 return $text;
1181         }
1182
1183         /**
1184          * Get the root page name text without a namespace, i.e. the leftmost part before any slashes
1185          *
1186          * @par Example:
1187          * @code
1188          * Title::newFromText('User:Foo/Bar/Baz')->getRootText();
1189          * # returns: 'Foo'
1190          * @endcode
1191          *
1192          * @return String Root name
1193          * @since 1.20
1194          */
1195         public function getRootText() {
1196                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1197                         return $this->getText();
1198                 }
1199
1200                 return strtok( $this->getText(), '/' );
1201         }
1202
1203         /**
1204          * Get the root page name title, i.e. the leftmost part before any slashes
1205          *
1206          * @par Example:
1207          * @code
1208          * Title::newFromText('User:Foo/Bar/Baz')->getRootTitle();
1209          * # returns: Title{User:Foo}
1210          * @endcode
1211          *
1212          * @return Title Root title
1213          * @since 1.20
1214          */
1215         public function getRootTitle() {
1216                 return Title::makeTitle( $this->getNamespace(), $this->getRootText() );
1217         }
1218
1219         /**
1220          * Get the base page name without a namespace, i.e. the part before the subpage name
1221          *
1222          * @par Example:
1223          * @code
1224          * Title::newFromText('User:Foo/Bar/Baz')->getBaseText();
1225          * # returns: 'Foo/Bar'
1226          * @endcode
1227          *
1228          * @return String Base name
1229          */
1230         public function getBaseText() {
1231                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1232                         return $this->getText();
1233                 }
1234
1235                 $parts = explode( '/', $this->getText() );
1236                 # Don't discard the real title if there's no subpage involved
1237                 if ( count( $parts ) > 1 ) {
1238                         unset( $parts[count( $parts ) - 1] );
1239                 }
1240                 return implode( '/', $parts );
1241         }
1242
1243         /**
1244          * Get the base page name title, i.e. the part before the subpage name
1245          *
1246          * @par Example:
1247          * @code
1248          * Title::newFromText('User:Foo/Bar/Baz')->getBaseTitle();
1249          * # returns: Title{User:Foo/Bar}
1250          * @endcode
1251          *
1252          * @return Title Base title
1253          * @since 1.20
1254          */
1255         public function getBaseTitle() {
1256                 return Title::makeTitle( $this->getNamespace(), $this->getBaseText() );
1257         }
1258
1259         /**
1260          * Get the lowest-level subpage name, i.e. the rightmost part after any slashes
1261          *
1262          * @par Example:
1263          * @code
1264          * Title::newFromText('User:Foo/Bar/Baz')->getSubpageText();
1265          * # returns: "Baz"
1266          * @endcode
1267          *
1268          * @return String Subpage name
1269          */
1270         public function getSubpageText() {
1271                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1272                         return( $this->mTextform );
1273                 }
1274                 $parts = explode( '/', $this->mTextform );
1275                 return( $parts[count( $parts ) - 1] );
1276         }
1277
1278         /**
1279          * Get the title for a subpage of the current page
1280          *
1281          * @par Example:
1282          * @code
1283          * Title::newFromText('User:Foo/Bar/Baz')->getSubpage("Asdf");
1284          * # returns: Title{User:Foo/Bar/Baz/Asdf}
1285          * @endcode
1286          *
1287          * @param $text String The subpage name to add to the title
1288          * @return Title Subpage title
1289          * @since 1.20
1290          */
1291         public function getSubpage( $text ) {
1292                 return Title::makeTitleSafe( $this->getNamespace(), $this->getText() . '/' . $text );
1293         }
1294
1295         /**
1296          * Get the HTML-escaped displayable text form.
1297          * Used for the title field in <a> tags.
1298          *
1299          * @return String the text, including any prefixes
1300          */
1301         public function getEscapedText() {
1302                 wfDeprecated( __METHOD__, '1.19' );
1303                 return htmlspecialchars( $this->getPrefixedText() );
1304         }
1305
1306         /**
1307          * Get a URL-encoded form of the subpage text
1308          *
1309          * @return String URL-encoded subpage name
1310          */
1311         public function getSubpageUrlForm() {
1312                 $text = $this->getSubpageText();
1313                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
1314                 return( $text );
1315         }
1316
1317         /**
1318          * Get a URL-encoded title (not an actual URL) including interwiki
1319          *
1320          * @return String the URL-encoded form
1321          */
1322         public function getPrefixedURL() {
1323                 $s = $this->prefix( $this->mDbkeyform );
1324                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
1325                 return $s;
1326         }
1327
1328         /**
1329          * Helper to fix up the get{Local,Full,Link,Canonical}URL args
1330          * get{Canonical,Full,Link,Local}URL methods accepted an optional
1331          * second argument named variant. This was deprecated in favor
1332          * of passing an array of option with a "variant" key
1333          * Once $query2 is removed for good, this helper can be dropped
1334          * andthe wfArrayToCgi moved to getLocalURL();
1335          *
1336          * @since 1.19 (r105919)
1337          * @param $query
1338          * @param $query2 bool
1339          * @return String
1340          */
1341         private static function fixUrlQueryArgs( $query, $query2 = false ) {
1342                 if( $query2 !== false ) {
1343                         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" );
1344                 }
1345                 if ( is_array( $query ) ) {
1346                         $query = wfArrayToCgi( $query );
1347                 }
1348                 if ( $query2 ) {
1349                         if ( is_string( $query2 ) ) {
1350                                 // $query2 is a string, we will consider this to be
1351                                 // a deprecated $variant argument and add it to the query
1352                                 $query2 = wfArrayToCgi( array( 'variant' => $query2 ) );
1353                         } else {
1354                                 $query2 = wfArrayToCgi( $query2 );
1355                         }
1356                         // If we have $query content add a & to it first
1357                         if ( $query ) {
1358                                 $query .= '&';
1359                         }
1360                         // Now append the queries together
1361                         $query .= $query2;
1362                 }
1363                 return $query;
1364         }
1365
1366         /**
1367          * Get a real URL referring to this title, with interwiki link and
1368          * fragment
1369          *
1370          * See getLocalURL for the arguments.
1371          *
1372          * @see self::getLocalURL
1373          * @see wfExpandUrl
1374          * @param $query
1375          * @param $query2 bool
1376          * @param $proto Protocol type to use in URL
1377          * @return String the URL
1378          */
1379         public function getFullURL( $query = '', $query2 = false, $proto = PROTO_RELATIVE ) {
1380                 $query = self::fixUrlQueryArgs( $query, $query2 );
1381
1382                 # Hand off all the decisions on urls to getLocalURL
1383                 $url = $this->getLocalURL( $query );
1384
1385                 # Expand the url to make it a full url. Note that getLocalURL has the
1386                 # potential to output full urls for a variety of reasons, so we use
1387                 # wfExpandUrl instead of simply prepending $wgServer
1388                 $url = wfExpandUrl( $url, $proto );
1389
1390                 # Finally, add the fragment.
1391                 $url .= $this->getFragmentForURL();
1392
1393                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
1394                 return $url;
1395         }
1396
1397         /**
1398          * Get a URL with no fragment or server name.  If this page is generated
1399          * with action=render, $wgServer is prepended.
1400          *
1401
1402          * @param $query string|array an optional query string,
1403          *   not used for interwiki links. Can be specified as an associative array as well,
1404          *   e.g., array( 'action' => 'edit' ) (keys and values will be URL-escaped).
1405          *   Some query patterns will trigger various shorturl path replacements.
1406          * @param $query2 Mixed: An optional secondary query array. This one MUST
1407          *   be an array. If a string is passed it will be interpreted as a deprecated
1408          *   variant argument and urlencoded into a variant= argument.
1409          *   This second query argument will be added to the $query
1410          *   The second parameter is deprecated since 1.19. Pass it as a key,value
1411          *   pair in the first parameter array instead.
1412          *
1413          * @return String the URL
1414          */
1415         public function getLocalURL( $query = '', $query2 = false ) {
1416                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
1417
1418                 $query = self::fixUrlQueryArgs( $query, $query2 );
1419
1420                 $interwiki = Interwiki::fetch( $this->mInterwiki );
1421                 if ( $interwiki ) {
1422                         $namespace = $this->getNsText();
1423                         if ( $namespace != '' ) {
1424                                 # Can this actually happen? Interwikis shouldn't be parsed.
1425                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
1426                                 $namespace .= ':';
1427                         }
1428                         $url = $interwiki->getURL( $namespace . $this->getDBkey() );
1429                         $url = wfAppendQuery( $url, $query );
1430                 } else {
1431                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
1432                         if ( $query == '' ) {
1433                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
1434                                 wfRunHooks( 'GetLocalURL::Article', array( &$this, &$url ) );
1435                         } else {
1436                                 global $wgVariantArticlePath, $wgActionPaths;
1437                                 $url = false;
1438                                 $matches = array();
1439
1440                                 if ( !empty( $wgActionPaths ) &&
1441                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
1442                                 {
1443                                         $action = urldecode( $matches[2] );
1444                                         if ( isset( $wgActionPaths[$action] ) ) {
1445                                                 $query = $matches[1];
1446                                                 if ( isset( $matches[4] ) ) {
1447                                                         $query .= $matches[4];
1448                                                 }
1449                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
1450                                                 if ( $query != '' ) {
1451                                                         $url = wfAppendQuery( $url, $query );
1452                                                 }
1453                                         }
1454                                 }
1455
1456                                 if ( $url === false &&
1457                                         $wgVariantArticlePath &&
1458                                         $this->getPageLanguage()->hasVariants() &&
1459                                         preg_match( '/^variant=([^&]*)$/', $query, $matches ) )
1460                                 {
1461                                         $variant = urldecode( $matches[1] );
1462                                         if ( $this->getPageLanguage()->hasVariant( $variant ) ) {
1463                                                 // Only do the variant replacement if the given variant is a valid
1464                                                 // variant for the page's language.
1465                                                 $url = str_replace( '$2', urlencode( $variant ), $wgVariantArticlePath );
1466                                                 $url = str_replace( '$1', $dbkey, $url );
1467                                         }
1468                                 }
1469
1470                                 if ( $url === false ) {
1471                                         if ( $query == '-' ) {
1472                                                 $query = '';
1473                                         }
1474                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
1475                                 }
1476                         }
1477
1478                         wfRunHooks( 'GetLocalURL::Internal', array( &$this, &$url, $query ) );
1479
1480                         // @todo FIXME: This causes breakage in various places when we
1481                         // actually expected a local URL and end up with dupe prefixes.
1482                         if ( $wgRequest->getVal( 'action' ) == 'render' ) {
1483                                 $url = $wgServer . $url;
1484                         }
1485                 }
1486                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
1487                 return $url;
1488         }
1489
1490         /**
1491          * Get a URL that's the simplest URL that will be valid to link, locally,
1492          * to the current Title.  It includes the fragment, but does not include
1493          * the server unless action=render is used (or the link is external).  If
1494          * there's a fragment but the prefixed text is empty, we just return a link
1495          * to the fragment.
1496          *
1497          * The result obviously should not be URL-escaped, but does need to be
1498          * HTML-escaped if it's being output in HTML.
1499          *
1500          * See getLocalURL for the arguments.
1501          *
1502          * @param $query
1503          * @param $query2 bool
1504          * @param $proto Protocol to use; setting this will cause a full URL to be used
1505          * @see self::getLocalURL
1506          * @return String the URL
1507          */
1508         public function getLinkURL( $query = '', $query2 = false, $proto = PROTO_RELATIVE ) {
1509                 wfProfileIn( __METHOD__ );
1510                 if ( $this->isExternal() || $proto !== PROTO_RELATIVE ) {
1511                         $ret = $this->getFullURL( $query, $query2, $proto );
1512                 } elseif ( $this->getPrefixedText() === '' && $this->getFragment() !== '' ) {
1513                         $ret = $this->getFragmentForURL();
1514                 } else {
1515                         $ret = $this->getLocalURL( $query, $query2 ) . $this->getFragmentForURL();
1516                 }
1517                 wfProfileOut( __METHOD__ );
1518                 return $ret;
1519         }
1520
1521         /**
1522          * Get an HTML-escaped version of the URL form, suitable for
1523          * using in a link, without a server name or fragment
1524          *
1525          * See getLocalURL for the arguments.
1526          *
1527          * @see self::getLocalURL
1528          * @param $query string
1529          * @param $query2 bool|string
1530          * @return String the URL
1531          */
1532         public function escapeLocalURL( $query = '', $query2 = false ) {
1533                 wfDeprecated( __METHOD__, '1.19' );
1534                 return htmlspecialchars( $this->getLocalURL( $query, $query2 ) );
1535         }
1536
1537         /**
1538          * Get an HTML-escaped version of the URL form, suitable for
1539          * using in a link, including the server name and fragment
1540          *
1541          * See getLocalURL for the arguments.
1542          *
1543          * @see self::getLocalURL
1544          * @return String the URL
1545          */
1546         public function escapeFullURL( $query = '', $query2 = false ) {
1547                 wfDeprecated( __METHOD__, '1.19' );
1548                 return htmlspecialchars( $this->getFullURL( $query, $query2 ) );
1549         }
1550
1551         /**
1552          * Get the URL form for an internal link.
1553          * - Used in various Squid-related code, in case we have a different
1554          * internal hostname for the server from the exposed one.
1555          *
1556          * This uses $wgInternalServer to qualify the path, or $wgServer
1557          * if $wgInternalServer is not set. If the server variable used is
1558          * protocol-relative, the URL will be expanded to http://
1559          *
1560          * See getLocalURL for the arguments.
1561          *
1562          * @see self::getLocalURL
1563          * @return String the URL
1564          */
1565         public function getInternalURL( $query = '', $query2 = false ) {
1566                 global $wgInternalServer, $wgServer;
1567                 $query = self::fixUrlQueryArgs( $query, $query2 );
1568                 $server = $wgInternalServer !== false ? $wgInternalServer : $wgServer;
1569                 $url = wfExpandUrl( $server . $this->getLocalURL( $query ), PROTO_HTTP );
1570                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
1571                 return $url;
1572         }
1573
1574         /**
1575          * Get the URL for a canonical link, for use in things like IRC and
1576          * e-mail notifications. Uses $wgCanonicalServer and the
1577          * GetCanonicalURL hook.
1578          *
1579          * NOTE: Unlike getInternalURL(), the canonical URL includes the fragment
1580          *
1581          * See getLocalURL for the arguments.
1582          *
1583          * @see self::getLocalURL
1584          * @return string The URL
1585          * @since 1.18
1586          */
1587         public function getCanonicalURL( $query = '', $query2 = false ) {
1588                 $query = self::fixUrlQueryArgs( $query, $query2 );
1589                 $url = wfExpandUrl( $this->getLocalURL( $query ) . $this->getFragmentForURL(), PROTO_CANONICAL );
1590                 wfRunHooks( 'GetCanonicalURL', array( &$this, &$url, $query ) );
1591                 return $url;
1592         }
1593
1594         /**
1595          * HTML-escaped version of getCanonicalURL()
1596          *
1597          * See getLocalURL for the arguments.
1598          *
1599          * @see self::getLocalURL
1600          * @since 1.18
1601          * @return string
1602          */
1603         public function escapeCanonicalURL( $query = '', $query2 = false ) {
1604                 wfDeprecated( __METHOD__, '1.19' );
1605                 return htmlspecialchars( $this->getCanonicalURL( $query, $query2 ) );
1606         }
1607
1608         /**
1609          * Get the edit URL for this Title
1610          *
1611          * @return String the URL, or a null string if this is an
1612          *  interwiki link
1613          */
1614         public function getEditURL() {
1615                 if ( $this->mInterwiki != '' ) {
1616                         return '';
1617                 }
1618                 $s = $this->getLocalURL( 'action=edit' );
1619
1620                 return $s;
1621         }
1622
1623         /**
1624          * Is $wgUser watching this page?
1625          *
1626          * @deprecated in 1.20; use User::isWatched() instead.
1627          * @return Bool
1628          */
1629         public function userIsWatching() {
1630                 global $wgUser;
1631
1632                 if ( is_null( $this->mWatched ) ) {
1633                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn() ) {
1634                                 $this->mWatched = false;
1635                         } else {
1636                                 $this->mWatched = $wgUser->isWatched( $this );
1637                         }
1638                 }
1639                 return $this->mWatched;
1640         }
1641
1642         /**
1643          * Can $wgUser read this page?
1644          *
1645          * @deprecated in 1.19; use userCan(), quickUserCan() or getUserPermissionsErrors() instead
1646          * @return Bool
1647          * @todo fold these checks into userCan()
1648          */
1649         public function userCanRead() {
1650                 wfDeprecated( __METHOD__, '1.19' );
1651                 return $this->userCan( 'read' );
1652         }
1653
1654         /**
1655          * Can $user perform $action on this page?
1656          * This skips potentially expensive cascading permission checks
1657          * as well as avoids expensive error formatting
1658          *
1659          * Suitable for use for nonessential UI controls in common cases, but
1660          * _not_ for functional access control.
1661          *
1662          * May provide false positives, but should never provide a false negative.
1663          *
1664          * @param $action String action that permission needs to be checked for
1665          * @param $user User to check (since 1.19); $wgUser will be used if not
1666          *              provided.
1667          * @return Bool
1668          */
1669         public function quickUserCan( $action, $user = null ) {
1670                 return $this->userCan( $action, $user, false );
1671         }
1672
1673         /**
1674          * Can $user perform $action on this page?
1675          *
1676          * @param $action String action that permission needs to be checked for
1677          * @param $user User to check (since 1.19); $wgUser will be used if not
1678          *   provided.
1679          * @param $doExpensiveQueries Bool Set this to false to avoid doing
1680          *   unnecessary queries.
1681          * @return Bool
1682          */
1683         public function userCan( $action, $user = null, $doExpensiveQueries = true ) {
1684                 if ( !$user instanceof User ) {
1685                         global $wgUser;
1686                         $user = $wgUser;
1687                 }
1688                 return !count( $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries, true ) );
1689         }
1690
1691         /**
1692          * Can $user perform $action on this page?
1693          *
1694          * @todo FIXME: This *does not* check throttles (User::pingLimiter()).
1695          *
1696          * @param $action String action that permission needs to be checked for
1697          * @param $user User to check
1698          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary
1699          *   queries by skipping checks for cascading protections and user blocks.
1700          * @param $ignoreErrors Array of Strings Set this to a list of message keys
1701          *   whose corresponding errors may be ignored.
1702          * @return Array of arguments to wfMessage to explain permissions problems.
1703          */
1704         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1705                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1706
1707                 // Remove the errors being ignored.
1708                 foreach ( $errors as $index => $error ) {
1709                         $error_key = is_array( $error ) ? $error[0] : $error;
1710
1711                         if ( in_array( $error_key, $ignoreErrors ) ) {
1712                                 unset( $errors[$index] );
1713                         }
1714                 }
1715
1716                 return $errors;
1717         }
1718
1719         /**
1720          * Permissions checks that fail most often, and which are easiest to test.
1721          *
1722          * @param $action String the action to check
1723          * @param $user User user to check
1724          * @param $errors Array list of current errors
1725          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1726          * @param $short Boolean short circuit on first error
1727          *
1728          * @return Array list of errors
1729          */
1730         private function checkQuickPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1731                 if ( $action == 'create' ) {
1732                         if (
1733                                 ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1734                                 ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) )
1735                         ) {
1736                                 $errors[] = $user->isAnon() ? array( 'nocreatetext' ) : array( 'nocreate-loggedin' );
1737                         }
1738                 } elseif ( $action == 'move' ) {
1739                         if ( !$user->isAllowed( 'move-rootuserpages' )
1740                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1741                                 // Show user page-specific message only if the user can move other pages
1742                                 $errors[] = array( 'cant-move-user-page' );
1743                         }
1744
1745                         // Check if user is allowed to move files if it's a file
1746                         if ( $this->mNamespace == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1747                                 $errors[] = array( 'movenotallowedfile' );
1748                         }
1749
1750                         if ( !$user->isAllowed( 'move' ) ) {
1751                                 // User can't move anything
1752                                 $userCanMove = User::groupHasPermission( 'user', 'move' );
1753                                 $autoconfirmedCanMove = User::groupHasPermission( 'autoconfirmed', 'move' );
1754                                 if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
1755                                         // custom message if logged-in users without any special rights can move
1756                                         $errors[] = array( 'movenologintext' );
1757                                 } else {
1758                                         $errors[] = array( 'movenotallowed' );
1759                                 }
1760                         }
1761                 } elseif ( $action == 'move-target' ) {
1762                         if ( !$user->isAllowed( 'move' ) ) {
1763                                 // User can't move anything
1764                                 $errors[] = array( 'movenotallowed' );
1765                         } elseif ( !$user->isAllowed( 'move-rootuserpages' )
1766                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1767                                 // Show user page-specific message only if the user can move other pages
1768                                 $errors[] = array( 'cant-move-to-user-page' );
1769                         }
1770                 } elseif ( !$user->isAllowed( $action ) ) {
1771                         $errors[] = $this->missingPermissionError( $action, $short );
1772                 }
1773
1774                 return $errors;
1775         }
1776
1777         /**
1778          * Add the resulting error code to the errors array
1779          *
1780          * @param $errors Array list of current errors
1781          * @param $result Mixed result of errors
1782          *
1783          * @return Array list of errors
1784          */
1785         private function resultToError( $errors, $result ) {
1786                 if ( is_array( $result ) && count( $result ) && !is_array( $result[0] ) ) {
1787                         // A single array representing an error
1788                         $errors[] = $result;
1789                 } elseif ( is_array( $result ) && is_array( $result[0] ) ) {
1790                         // A nested array representing multiple errors
1791                         $errors = array_merge( $errors, $result );
1792                 } elseif ( $result !== '' && is_string( $result ) ) {
1793                         // A string representing a message-id
1794                         $errors[] = array( $result );
1795                 } elseif ( $result === false ) {
1796                         // a generic "We don't want them to do that"
1797                         $errors[] = array( 'badaccess-group0' );
1798                 }
1799                 return $errors;
1800         }
1801
1802         /**
1803          * Check various permission hooks
1804          *
1805          * @param $action String the action to check
1806          * @param $user User user to check
1807          * @param $errors Array list of current errors
1808          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1809          * @param $short Boolean short circuit on first error
1810          *
1811          * @return Array list of errors
1812          */
1813         private function checkPermissionHooks( $action, $user, $errors, $doExpensiveQueries, $short ) {
1814                 // Use getUserPermissionsErrors instead
1815                 $result = '';
1816                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1817                         return $result ? array() : array( array( 'badaccess-group0' ) );
1818                 }
1819                 // Check getUserPermissionsErrors hook
1820                 if ( !wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1821                         $errors = $this->resultToError( $errors, $result );
1822                 }
1823                 // Check getUserPermissionsErrorsExpensive hook
1824                 if (
1825                         $doExpensiveQueries
1826                         && !( $short && count( $errors ) > 0 )
1827                         && !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) )
1828                 ) {
1829                         $errors = $this->resultToError( $errors, $result );
1830                 }
1831
1832                 return $errors;
1833         }
1834
1835         /**
1836          * Check permissions on special pages & namespaces
1837          *
1838          * @param $action String the action to check
1839          * @param $user User user to check
1840          * @param $errors Array list of current errors
1841          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1842          * @param $short Boolean short circuit on first error
1843          *
1844          * @return Array list of errors
1845          */
1846         private function checkSpecialsAndNSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1847                 # Only 'createaccount' can be performed on special pages,
1848                 # which don't actually exist in the DB.
1849                 if ( NS_SPECIAL == $this->mNamespace && $action !== 'createaccount' ) {
1850                         $errors[] = array( 'ns-specialprotected' );
1851                 }
1852
1853                 # Check $wgNamespaceProtection for restricted namespaces
1854                 if ( $this->isNamespaceProtected( $user ) ) {
1855                         $ns = $this->mNamespace == NS_MAIN ?
1856                                 wfMessage( 'nstab-main' )->text() : $this->getNsText();
1857                         $errors[] = $this->mNamespace == NS_MEDIAWIKI ?
1858                                 array( 'protectedinterface' ) : array( 'namespaceprotected', $ns );
1859                 }
1860
1861                 return $errors;
1862         }
1863
1864         /**
1865          * Check CSS/JS sub-page permissions
1866          *
1867          * @param $action String the action to check
1868          * @param $user User user to check
1869          * @param $errors Array list of current errors
1870          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1871          * @param $short Boolean short circuit on first error
1872          *
1873          * @return Array list of errors
1874          */
1875         private function checkCSSandJSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1876                 # Protect css/js subpages of user pages
1877                 # XXX: this might be better using restrictions
1878                 # XXX: right 'editusercssjs' is deprecated, for backward compatibility only
1879                 if ( $action != 'patrol' && !$user->isAllowed( 'editusercssjs' )
1880                                 && !preg_match( '/^' . preg_quote( $user->getName(), '/' ) . '\//', $this->mTextform ) ) {
1881                         if ( $this->isCssSubpage() && !$user->isAllowed( 'editusercss' ) ) {
1882                                 $errors[] = array( 'customcssprotected' );
1883                         } elseif ( $this->isJsSubpage() && !$user->isAllowed( 'edituserjs' ) ) {
1884                                 $errors[] = array( 'customjsprotected' );
1885                         }
1886                 }
1887
1888                 return $errors;
1889         }
1890
1891         /**
1892          * Check against page_restrictions table requirements on this
1893          * page. The user must possess all required rights for this
1894          * action.
1895          *
1896          * @param $action String the action to check
1897          * @param $user User user to check
1898          * @param $errors Array list of current errors
1899          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1900          * @param $short Boolean short circuit on first error
1901          *
1902          * @return Array list of errors
1903          */
1904         private function checkPageRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1905                 foreach ( $this->getRestrictions( $action ) as $right ) {
1906                         // Backwards compatibility, rewrite sysop -> protect
1907                         if ( $right == 'sysop' ) {
1908                                 $right = 'protect';
1909                         }
1910                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1911                                 // Users with 'editprotected' permission can edit protected pages
1912                                 // without cascading option turned on.
1913                                 if ( $action != 'edit' || !$user->isAllowed( 'editprotected' )
1914                                         || $this->mCascadeRestriction )
1915                                 {
1916                                         $errors[] = array( 'protectedpagetext', $right );
1917                                 }
1918                         }
1919                 }
1920
1921                 return $errors;
1922         }
1923
1924         /**
1925          * Check restrictions on cascading pages.
1926          *
1927          * @param $action String the action to check
1928          * @param $user User to check
1929          * @param $errors Array list of current errors
1930          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1931          * @param $short Boolean short circuit on first error
1932          *
1933          * @return Array list of errors
1934          */
1935         private function checkCascadingSourcesRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1936                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1937                         # We /could/ use the protection level on the source page, but it's
1938                         # fairly ugly as we have to establish a precedence hierarchy for pages
1939                         # included by multiple cascade-protected pages. So just restrict
1940                         # it to people with 'protect' permission, as they could remove the
1941                         # protection anyway.
1942                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1943                         # Cascading protection depends on more than this page...
1944                         # Several cascading protected pages may include this page...
1945                         # Check each cascading level
1946                         # This is only for protection restrictions, not for all actions
1947                         if ( isset( $restrictions[$action] ) ) {
1948                                 foreach ( $restrictions[$action] as $right ) {
1949                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1950                                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1951                                                 $pages = '';
1952                                                 foreach ( $cascadingSources as $page )
1953                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1954                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1955                                         }
1956                                 }
1957                         }
1958                 }
1959
1960                 return $errors;
1961         }
1962
1963         /**
1964          * Check action permissions not already checked in checkQuickPermissions
1965          *
1966          * @param $action String the action to check
1967          * @param $user User to check
1968          * @param $errors Array list of current errors
1969          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1970          * @param $short Boolean short circuit on first error
1971          *
1972          * @return Array list of errors
1973          */
1974         private function checkActionPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1975                 global $wgDeleteRevisionsLimit, $wgLang;
1976
1977                 if ( $action == 'protect' ) {
1978                         if ( count( $this->getUserPermissionsErrorsInternal( 'edit', $user, $doExpensiveQueries, true ) ) ) {
1979                                 // If they can't edit, they shouldn't protect.
1980                                 $errors[] = array( 'protect-cantedit' );
1981                         }
1982                 } elseif ( $action == 'create' ) {
1983                         $title_protection = $this->getTitleProtection();
1984                         if( $title_protection ) {
1985                                 if( $title_protection['pt_create_perm'] == 'sysop' ) {
1986                                         $title_protection['pt_create_perm'] = 'protect'; // B/C
1987                                 }
1988                                 if( $title_protection['pt_create_perm'] == '' ||
1989                                         !$user->isAllowed( $title_protection['pt_create_perm'] ) )
1990                                 {
1991                                         $errors[] = array( 'titleprotected', User::whoIs( $title_protection['pt_user'] ), $title_protection['pt_reason'] );
1992                                 }
1993                         }
1994                 } elseif ( $action == 'move' ) {
1995                         // Check for immobile pages
1996                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1997                                 // Specific message for this case
1998                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1999                         } elseif ( !$this->isMovable() ) {
2000                                 // Less specific message for rarer cases
2001                                 $errors[] = array( 'immobile-source-page' );
2002                         }
2003                 } elseif ( $action == 'move-target' ) {
2004                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
2005                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
2006                         } elseif ( !$this->isMovable() ) {
2007                                 $errors[] = array( 'immobile-target-page' );
2008                         }
2009                 } elseif ( $action == 'delete' ) {
2010                         if ( $doExpensiveQueries && $wgDeleteRevisionsLimit
2011                                 && !$this->userCan( 'bigdelete', $user ) && $this->isBigDeletion() )
2012                         {
2013                                 $errors[] = array( 'delete-toobig', $wgLang->formatNum( $wgDeleteRevisionsLimit ) );
2014                         }
2015                 }
2016                 return $errors;
2017         }
2018
2019         /**
2020          * Check that the user isn't blocked from editting.
2021          *
2022          * @param $action String the action to check
2023          * @param $user User to check
2024          * @param $errors Array list of current errors
2025          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
2026          * @param $short Boolean short circuit on first error
2027          *
2028          * @return Array list of errors
2029          */
2030         private function checkUserBlock( $action, $user, $errors, $doExpensiveQueries, $short ) {
2031                 // Account creation blocks handled at userlogin.
2032                 // Unblocking handled in SpecialUnblock
2033                 if( !$doExpensiveQueries || in_array( $action, array( 'createaccount', 'unblock' ) ) ) {
2034                         return $errors;
2035                 }
2036
2037                 global $wgContLang, $wgLang, $wgEmailConfirmToEdit;
2038
2039                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() ) {
2040                         $errors[] = array( 'confirmedittext' );
2041                 }
2042
2043                 if ( ( $action == 'edit' || $action == 'create' ) && !$user->isBlockedFrom( $this ) ) {
2044                         // Don't block the user from editing their own talk page unless they've been
2045                         // explicitly blocked from that too.
2046                 } elseif( $user->isBlocked() && $user->mBlock->prevents( $action ) !== false ) {
2047                         $block = $user->getBlock();
2048
2049                         // This is from OutputPage::blockedPage
2050                         // Copied at r23888 by werdna
2051
2052                         $id = $user->blockedBy();
2053                         $reason = $user->blockedFor();
2054                         if ( $reason == '' ) {
2055                                 $reason = wfMessage( 'blockednoreason' )->text();
2056                         }
2057                         $ip = $user->getRequest()->getIP();
2058
2059                         if ( is_numeric( $id ) ) {
2060                                 $name = User::whoIs( $id );
2061                         } else {
2062                                 $name = $id;
2063                         }
2064
2065                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
2066                         $blockid = $block->getId();
2067                         $blockExpiry = $block->getExpiry();
2068                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $block->mTimestamp ), true );
2069                         if ( $blockExpiry == 'infinity' ) {
2070                                 $blockExpiry = wfMessage( 'infiniteblock' )->text();
2071                         } else {
2072                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
2073                         }
2074
2075                         $intended = strval( $block->getTarget() );
2076
2077                         $errors[] = array( ( $block->mAuto ? 'autoblockedtext' : 'blockedtext' ), $link, $reason, $ip, $name,
2078                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
2079                 }
2080
2081                 return $errors;
2082         }
2083
2084         /**
2085          * Check that the user is allowed to read this page.
2086          *
2087          * @param $action String the action to check
2088          * @param $user User to check
2089          * @param $errors Array list of current errors
2090          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
2091          * @param $short Boolean short circuit on first error
2092          *
2093          * @return Array list of errors
2094          */
2095         private function checkReadPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
2096                 global $wgWhitelistRead, $wgWhitelistReadRegexp, $wgRevokePermissions;
2097                 static $useShortcut = null;
2098
2099                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
2100                 if ( is_null( $useShortcut ) ) {
2101                         $useShortcut = true;
2102                         if ( !User::groupHasPermission( '*', 'read' ) ) {
2103                                 # Not a public wiki, so no shortcut
2104                                 $useShortcut = false;
2105                         } elseif ( !empty( $wgRevokePermissions ) ) {
2106                                 /**
2107                                  * Iterate through each group with permissions being revoked (key not included since we don't care
2108                                  * what the group name is), then check if the read permission is being revoked. If it is, then
2109                                  * we don't use the shortcut below since the user might not be able to read, even though anon
2110                                  * reading is allowed.
2111                                  */
2112                                 foreach ( $wgRevokePermissions as $perms ) {
2113                                         if ( !empty( $perms['read'] ) ) {
2114                                                 # We might be removing the read right from the user, so no shortcut
2115                                                 $useShortcut = false;
2116                                                 break;
2117                                         }
2118                                 }
2119                         }
2120                 }
2121
2122                 $whitelisted = false;
2123                 if ( $useShortcut ) {
2124                         # Shortcut for public wikis, allows skipping quite a bit of code
2125                         $whitelisted = true;
2126                 } elseif ( $user->isAllowed( 'read' ) ) {
2127                         # If the user is allowed to read pages, he is allowed to read all pages
2128                         $whitelisted = true;
2129                 } elseif ( $this->isSpecial( 'Userlogin' )
2130                         || $this->isSpecial( 'ChangePassword' )
2131                         || $this->isSpecial( 'PasswordReset' )
2132                 ) {
2133                         # Always grant access to the login page.
2134                         # Even anons need to be able to log in.
2135                         $whitelisted = true;
2136                 } elseif ( is_array( $wgWhitelistRead ) && count( $wgWhitelistRead ) ) {
2137                         # Time to check the whitelist
2138                         # Only do these checks is there's something to check against
2139                         $name = $this->getPrefixedText();
2140                         $dbName = $this->getPrefixedDBKey();
2141
2142                         // Check for explicit whitelisting with and without underscores
2143                         if ( in_array( $name, $wgWhitelistRead, true ) || in_array( $dbName, $wgWhitelistRead, true ) ) {
2144                                 $whitelisted = true;
2145                         } elseif ( $this->getNamespace() == NS_MAIN ) {
2146                                 # Old settings might have the title prefixed with
2147                                 # a colon for main-namespace pages
2148                                 if ( in_array( ':' . $name, $wgWhitelistRead ) ) {
2149                                         $whitelisted = true;
2150                                 }
2151                         } elseif ( $this->isSpecialPage() ) {
2152                                 # If it's a special page, ditch the subpage bit and check again
2153                                 $name = $this->getDBkey();
2154                                 list( $name, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $name );
2155                                 if ( $name ) {
2156                                         $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
2157                                         if ( in_array( $pure, $wgWhitelistRead, true ) ) {
2158                                                 $whitelisted = true;
2159                                         }
2160                                 }
2161                         }
2162                 }
2163
2164                 if( !$whitelisted && is_array( $wgWhitelistReadRegexp ) && !empty( $wgWhitelistReadRegexp ) ) {
2165                         $name = $this->getPrefixedText();
2166                         // Check for regex whitelisting
2167                         foreach ( $wgWhitelistReadRegexp as $listItem ) {
2168                                 if ( preg_match( $listItem, $name ) ) {
2169                                         $whitelisted = true;
2170                                         break;
2171                                 }
2172                         }
2173                 }
2174
2175                 if ( !$whitelisted ) {
2176                         # If the title is not whitelisted, give extensions a chance to do so...
2177                         wfRunHooks( 'TitleReadWhitelist', array( $this, $user, &$whitelisted ) );
2178                         if ( !$whitelisted ) {
2179                                 $errors[] = $this->missingPermissionError( $action, $short );
2180                         }
2181                 }
2182
2183                 return $errors;
2184         }
2185
2186         /**
2187          * Get a description array when the user doesn't have the right to perform
2188          * $action (i.e. when User::isAllowed() returns false)
2189          *
2190          * @param $action String the action to check
2191          * @param $short Boolean short circuit on first error
2192          * @return Array list of errors
2193          */
2194         private function missingPermissionError( $action, $short ) {
2195                 // We avoid expensive display logic for quickUserCan's and such
2196                 if ( $short ) {
2197                         return array( 'badaccess-group0' );
2198                 }
2199
2200                 $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
2201                         User::getGroupsWithPermission( $action ) );
2202
2203                 if ( count( $groups ) ) {
2204                         global $wgLang;
2205                         return array(
2206                                 'badaccess-groups',
2207                                 $wgLang->commaList( $groups ),
2208                                 count( $groups )
2209                         );
2210                 } else {
2211                         return array( 'badaccess-group0' );
2212                 }
2213         }
2214
2215         /**
2216          * Can $user perform $action on this page? This is an internal function,
2217          * which checks ONLY that previously checked by userCan (i.e. it leaves out
2218          * checks on wfReadOnly() and blocks)
2219          *
2220          * @param $action String action that permission needs to be checked for
2221          * @param $user User to check
2222          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary queries.
2223          * @param $short Bool Set this to true to stop after the first permission error.
2224          * @return Array of arrays of the arguments to wfMessage to explain permissions problems.
2225          */
2226         protected function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true, $short = false ) {
2227                 wfProfileIn( __METHOD__ );
2228
2229                 # Read has special handling
2230                 if ( $action == 'read' ) {
2231                         $checks = array(
2232                                 'checkPermissionHooks',
2233                                 'checkReadPermissions',
2234                         );
2235                 } else {
2236                         $checks = array(
2237                                 'checkQuickPermissions',
2238                                 'checkPermissionHooks',
2239                                 'checkSpecialsAndNSPermissions',
2240                                 'checkCSSandJSPermissions',
2241                                 'checkPageRestrictions',
2242                                 'checkCascadingSourcesRestrictions',
2243                                 'checkActionPermissions',
2244                                 'checkUserBlock'
2245                         );
2246                 }
2247
2248                 $errors = array();
2249                 while( count( $checks ) > 0 &&
2250                                 !( $short && count( $errors ) > 0 ) ) {
2251                         $method = array_shift( $checks );
2252                         $errors = $this->$method( $action, $user, $errors, $doExpensiveQueries, $short );
2253                 }
2254
2255                 wfProfileOut( __METHOD__ );
2256                 return $errors;
2257         }
2258
2259         /**
2260          * Protect css subpages of user pages: can $wgUser edit
2261          * this page?
2262          *
2263          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2264          * @return Bool
2265          */
2266         public function userCanEditCssSubpage() {
2267                 global $wgUser;
2268                 wfDeprecated( __METHOD__, '1.19' );
2269                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'editusercss' ) )
2270                         || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2271         }
2272
2273         /**
2274          * Protect js subpages of user pages: can $wgUser edit
2275          * this page?
2276          *
2277          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2278          * @return Bool
2279          */
2280         public function userCanEditJsSubpage() {
2281                 global $wgUser;
2282                 wfDeprecated( __METHOD__, '1.19' );
2283                 return (
2284                         ( $wgUser->isAllowedAll( 'editusercssjs', 'edituserjs' ) )
2285                         || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform )
2286                 );
2287         }
2288
2289         /**
2290          * Get a filtered list of all restriction types supported by this wiki.
2291          * @param bool $exists True to get all restriction types that apply to
2292          * titles that do exist, False for all restriction types that apply to
2293          * titles that do not exist
2294          * @return array
2295          */
2296         public static function getFilteredRestrictionTypes( $exists = true ) {
2297                 global $wgRestrictionTypes;
2298                 $types = $wgRestrictionTypes;
2299                 if ( $exists ) {
2300                         # Remove the create restriction for existing titles
2301                         $types = array_diff( $types, array( 'create' ) );
2302                 } else {
2303                         # Only the create and upload restrictions apply to non-existing titles
2304                         $types = array_intersect( $types, array( 'create', 'upload' ) );
2305                 }
2306                 return $types;
2307         }
2308
2309         /**
2310          * Returns restriction types for the current Title
2311          *
2312          * @return array applicable restriction types
2313          */
2314         public function getRestrictionTypes() {
2315                 if ( $this->isSpecialPage() ) {
2316                         return array();
2317                 }
2318
2319                 $types = self::getFilteredRestrictionTypes( $this->exists() );
2320
2321                 if ( $this->getNamespace() != NS_FILE ) {
2322                         # Remove the upload restriction for non-file titles
2323                         $types = array_diff( $types, array( 'upload' ) );
2324                 }
2325
2326                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
2327
2328                 wfDebug( __METHOD__ . ': applicable restrictions to [[' .
2329                         $this->getPrefixedText() . ']] are {' . implode( ',', $types ) . "}\n" );
2330
2331                 return $types;
2332         }
2333
2334         /**
2335          * Is this title subject to title protection?
2336          * Title protection is the one applied against creation of such title.
2337          *
2338          * @return Mixed An associative array representing any existent title
2339          *   protection, or false if there's none.
2340          */
2341         private function getTitleProtection() {
2342                 // Can't protect pages in special namespaces
2343                 if ( $this->getNamespace() < 0 ) {
2344                         return false;
2345                 }
2346
2347                 // Can't protect pages that exist.
2348                 if ( $this->exists() ) {
2349                         return false;
2350                 }
2351
2352                 if ( !isset( $this->mTitleProtection ) ) {
2353                         $dbr = wfGetDB( DB_SLAVE );
2354                         $res = $dbr->select(
2355                                 'protected_titles',
2356                                 array( 'pt_user', 'pt_reason', 'pt_expiry', 'pt_create_perm' ),
2357                                 array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2358                                 __METHOD__
2359                         );
2360
2361                         // fetchRow returns false if there are no rows.
2362                         $this->mTitleProtection = $dbr->fetchRow( $res );
2363                 }
2364                 return $this->mTitleProtection;
2365         }
2366
2367         /**
2368          * Update the title protection status
2369          *
2370          * @deprecated in 1.19; will be removed in 1.20. Use WikiPage::doUpdateRestrictions() instead.
2371          * @param $create_perm String Permission required for creation
2372          * @param $reason String Reason for protection
2373          * @param $expiry String Expiry timestamp
2374          * @return boolean true
2375          */
2376         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
2377                 wfDeprecated( __METHOD__, '1.19' );
2378
2379                 global $wgUser;
2380
2381                 $limit = array( 'create' => $create_perm );
2382                 $expiry = array( 'create' => $expiry );
2383
2384                 $page = WikiPage::factory( $this );
2385                 $cascade = false;
2386                 $status = $page->doUpdateRestrictions( $limit, $expiry, $cascade, $reason, $wgUser );
2387
2388                 return $status->isOK();
2389         }
2390
2391         /**
2392          * Remove any title protection due to page existing
2393          */
2394         public function deleteTitleProtection() {
2395                 $dbw = wfGetDB( DB_MASTER );
2396
2397                 $dbw->delete(
2398                         'protected_titles',
2399                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2400                         __METHOD__
2401                 );
2402                 $this->mTitleProtection = false;
2403         }
2404
2405         /**
2406          * Is this page "semi-protected" - the *only* protection is autoconfirm?
2407          *
2408          * @param $action String Action to check (default: edit)
2409          * @return Bool
2410          */
2411         public function isSemiProtected( $action = 'edit' ) {
2412                 if ( $this->exists() ) {
2413                         $restrictions = $this->getRestrictions( $action );
2414                         if ( count( $restrictions ) > 0 ) {
2415                                 foreach ( $restrictions as $restriction ) {
2416                                         if ( strtolower( $restriction ) != 'autoconfirmed' ) {
2417                                                 return false;
2418                                         }
2419                                 }
2420                         } else {
2421                                 # Not protected
2422                                 return false;
2423                         }
2424                         return true;
2425                 } else {
2426                         # If it doesn't exist, it can't be protected
2427                         return false;
2428                 }
2429         }
2430
2431         /**
2432          * Does the title correspond to a protected article?
2433          *
2434          * @param $action String the action the page is protected from,
2435          * by default checks all actions.
2436          * @return Bool
2437          */
2438         public function isProtected( $action = '' ) {
2439                 global $wgRestrictionLevels;
2440
2441                 $restrictionTypes = $this->getRestrictionTypes();
2442
2443                 # Special pages have inherent protection
2444                 if( $this->isSpecialPage() ) {
2445                         return true;
2446                 }
2447
2448                 # Check regular protection levels
2449                 foreach ( $restrictionTypes as $type ) {
2450                         if ( $action == $type || $action == '' ) {
2451                                 $r = $this->getRestrictions( $type );
2452                                 foreach ( $wgRestrictionLevels as $level ) {
2453                                         if ( in_array( $level, $r ) && $level != '' ) {
2454                                                 return true;
2455                                         }
2456                                 }
2457                         }
2458                 }
2459
2460                 return false;
2461         }
2462
2463         /**
2464          * Determines if $user is unable to edit this page because it has been protected
2465          * by $wgNamespaceProtection.
2466          *
2467          * @param $user User object to check permissions
2468          * @return Bool
2469          */
2470         public function isNamespaceProtected( User $user ) {
2471                 global $wgNamespaceProtection;
2472
2473                 if ( isset( $wgNamespaceProtection[$this->mNamespace] ) ) {
2474                         foreach ( (array)$wgNamespaceProtection[$this->mNamespace] as $right ) {
2475                                 if ( $right != '' && !$user->isAllowed( $right ) ) {
2476                                         return true;
2477                                 }
2478                         }
2479                 }
2480                 return false;
2481         }
2482
2483         /**
2484          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
2485          *
2486          * @return Bool If the page is subject to cascading restrictions.
2487          */
2488         public function isCascadeProtected() {
2489                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
2490                 return ( $sources > 0 );
2491         }
2492
2493         /**
2494          * Cascading protection: Get the source of any cascading restrictions on this page.
2495          *
2496          * @param $getPages Bool Whether or not to retrieve the actual pages
2497          *        that the restrictions have come from.
2498          * @return Mixed Array of Title objects of the pages from which cascading restrictions
2499          *     have come, false for none, or true if such restrictions exist, but $getPages
2500          *     was not set.  The restriction array is an array of each type, each of which
2501          *     contains a array of unique groups.
2502          */
2503         public function getCascadeProtectionSources( $getPages = true ) {
2504                 global $wgContLang;
2505                 $pagerestrictions = array();
2506
2507                 if ( isset( $this->mCascadeSources ) && $getPages ) {
2508                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
2509                 } elseif ( isset( $this->mHasCascadingRestrictions ) && !$getPages ) {
2510                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
2511                 }
2512
2513                 wfProfileIn( __METHOD__ );
2514
2515                 $dbr = wfGetDB( DB_SLAVE );
2516
2517                 if ( $this->getNamespace() == NS_FILE ) {
2518                         $tables = array( 'imagelinks', 'page_restrictions' );
2519                         $where_clauses = array(
2520                                 'il_to' => $this->getDBkey(),
2521                                 'il_from=pr_page',
2522                                 'pr_cascade' => 1
2523                         );
2524                 } else {
2525                         $tables = array( 'templatelinks', 'page_restrictions' );
2526                         $where_clauses = array(
2527                                 'tl_namespace' => $this->getNamespace(),
2528                                 'tl_title' => $this->getDBkey(),
2529                                 'tl_from=pr_page',
2530                                 'pr_cascade' => 1
2531                         );
2532                 }
2533
2534                 if ( $getPages ) {
2535                         $cols = array( 'pr_page', 'page_namespace', 'page_title',
2536                                 'pr_expiry', 'pr_type', 'pr_level' );
2537                         $where_clauses[] = 'page_id=pr_page';
2538                         $tables[] = 'page';
2539                 } else {
2540                         $cols = array( 'pr_expiry' );
2541                 }
2542
2543                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
2544
2545                 $sources = $getPages ? array() : false;
2546                 $now = wfTimestampNow();
2547                 $purgeExpired = false;
2548
2549                 foreach ( $res as $row ) {
2550                         $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2551                         if ( $expiry > $now ) {
2552                                 if ( $getPages ) {
2553                                         $page_id = $row->pr_page;
2554                                         $page_ns = $row->page_namespace;
2555                                         $page_title = $row->page_title;
2556                                         $sources[$page_id] = Title::makeTitle( $page_ns, $page_title );
2557                                         # Add groups needed for each restriction type if its not already there
2558                                         # Make sure this restriction type still exists
2559
2560                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
2561                                                 $pagerestrictions[$row->pr_type] = array();
2562                                         }
2563
2564                                         if (
2565                                                 isset( $pagerestrictions[$row->pr_type] )
2566                                                 && !in_array( $row->pr_level, $pagerestrictions[$row->pr_type] )
2567                                         ) {
2568                                                 $pagerestrictions[$row->pr_type][] = $row->pr_level;
2569                                         }
2570                                 } else {
2571                                         $sources = true;
2572                                 }
2573                         } else {
2574                                 // Trigger lazy purge of expired restrictions from the db
2575                                 $purgeExpired = true;
2576                         }
2577                 }
2578                 if ( $purgeExpired ) {
2579                         Title::purgeExpiredRestrictions();
2580                 }
2581
2582                 if ( $getPages ) {
2583                         $this->mCascadeSources = $sources;
2584                         $this->mCascadingRestrictions = $pagerestrictions;
2585                 } else {
2586                         $this->mHasCascadingRestrictions = $sources;
2587                 }
2588
2589                 wfProfileOut( __METHOD__ );
2590                 return array( $sources, $pagerestrictions );
2591         }
2592
2593         /**
2594          * Accessor/initialisation for mRestrictions
2595          *
2596          * @param $action String action that permission needs to be checked for
2597          * @return Array of Strings the array of groups allowed to edit this article
2598          */
2599         public function getRestrictions( $action ) {
2600                 if ( !$this->mRestrictionsLoaded ) {
2601                         $this->loadRestrictions();
2602                 }
2603                 return isset( $this->mRestrictions[$action] )
2604                                 ? $this->mRestrictions[$action]
2605                                 : array();
2606         }
2607
2608         /**
2609          * Get the expiry time for the restriction against a given action
2610          *
2611          * @param $action
2612          * @return String|Bool 14-char timestamp, or 'infinity' if the page is protected forever
2613          *     or not protected at all, or false if the action is not recognised.
2614          */
2615         public function getRestrictionExpiry( $action ) {
2616                 if ( !$this->mRestrictionsLoaded ) {
2617                         $this->loadRestrictions();
2618                 }
2619                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2620         }
2621
2622         /**
2623          * Returns cascading restrictions for the current article
2624          *
2625          * @return Boolean
2626          */
2627         function areRestrictionsCascading() {
2628                 if ( !$this->mRestrictionsLoaded ) {
2629                         $this->loadRestrictions();
2630                 }
2631
2632                 return $this->mCascadeRestriction;
2633         }
2634
2635         /**
2636          * Loads a string into mRestrictions array
2637          *
2638          * @param $res Resource restrictions as an SQL result.
2639          * @param $oldFashionedRestrictions String comma-separated list of page
2640          *        restrictions from page table (pre 1.10)
2641          */
2642         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
2643                 $rows = array();
2644
2645                 foreach ( $res as $row ) {
2646                         $rows[] = $row;
2647                 }
2648
2649                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
2650         }
2651
2652         /**
2653          * Compiles list of active page restrictions from both page table (pre 1.10)
2654          * and page_restrictions table for this existing page.
2655          * Public for usage by LiquidThreads.
2656          *
2657          * @param $rows array of db result objects
2658          * @param $oldFashionedRestrictions string comma-separated list of page
2659          *        restrictions from page table (pre 1.10)
2660          */
2661         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
2662                 global $wgContLang;
2663                 $dbr = wfGetDB( DB_SLAVE );
2664
2665                 $restrictionTypes = $this->getRestrictionTypes();
2666
2667                 foreach ( $restrictionTypes as $type ) {
2668                         $this->mRestrictions[$type] = array();
2669                         $this->mRestrictionsExpiry[$type] = $wgContLang->formatExpiry( '', TS_MW );
2670                 }
2671
2672                 $this->mCascadeRestriction = false;
2673
2674                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2675
2676                 if ( $oldFashionedRestrictions === null ) {
2677                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2678                                 array( 'page_id' => $this->getArticleID() ), __METHOD__ );
2679                 }
2680
2681                 if ( $oldFashionedRestrictions != '' ) {
2682
2683                         foreach ( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2684                                 $temp = explode( '=', trim( $restrict ) );
2685                                 if ( count( $temp ) == 1 ) {
2686                                         // old old format should be treated as edit/move restriction
2687                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2688                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2689                                 } else {
2690                                         $restriction = trim( $temp[1] );
2691                                         if( $restriction != '' ) { //some old entries are empty
2692                                                 $this->mRestrictions[$temp[0]] = explode( ',', $restriction );
2693                                         }
2694                                 }
2695                         }
2696
2697                         $this->mOldRestrictions = true;
2698
2699                 }
2700
2701                 if ( count( $rows ) ) {
2702                         # Current system - load second to make them override.
2703                         $now = wfTimestampNow();
2704                         $purgeExpired = false;
2705
2706                         # Cycle through all the restrictions.
2707                         foreach ( $rows as $row ) {
2708
2709                                 // Don't take care of restrictions types that aren't allowed
2710                                 if ( !in_array( $row->pr_type, $restrictionTypes ) )
2711                                         continue;
2712
2713                                 // This code should be refactored, now that it's being used more generally,
2714                                 // But I don't really see any harm in leaving it in Block for now -werdna
2715                                 $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2716
2717                                 // Only apply the restrictions if they haven't expired!
2718                                 if ( !$expiry || $expiry > $now ) {
2719                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2720                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2721
2722                                         $this->mCascadeRestriction |= $row->pr_cascade;
2723                                 } else {
2724                                         // Trigger a lazy purge of expired restrictions
2725                                         $purgeExpired = true;
2726                                 }
2727                         }
2728
2729                         if ( $purgeExpired ) {
2730                                 Title::purgeExpiredRestrictions();
2731                         }
2732                 }
2733
2734                 $this->mRestrictionsLoaded = true;
2735         }
2736
2737         /**
2738          * Load restrictions from the page_restrictions table
2739          *
2740          * @param $oldFashionedRestrictions String comma-separated list of page
2741          *        restrictions from page table (pre 1.10)
2742          */
2743         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2744                 global $wgContLang;
2745                 if ( !$this->mRestrictionsLoaded ) {
2746                         if ( $this->exists() ) {
2747                                 $dbr = wfGetDB( DB_SLAVE );
2748
2749                                 $res = $dbr->select(
2750                                         'page_restrictions',
2751                                         array( 'pr_type', 'pr_expiry', 'pr_level', 'pr_cascade' ),
2752                                         array( 'pr_page' => $this->getArticleID() ),
2753                                         __METHOD__
2754                                 );
2755
2756                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2757                         } else {
2758                                 $title_protection = $this->getTitleProtection();
2759
2760                                 if ( $title_protection ) {
2761                                         $now = wfTimestampNow();
2762                                         $expiry = $wgContLang->formatExpiry( $title_protection['pt_expiry'], TS_MW );
2763
2764                                         if ( !$expiry || $expiry > $now ) {
2765                                                 // Apply the restrictions
2766                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2767                                                 $this->mRestrictions['create'] = explode( ',', trim( $title_protection['pt_create_perm'] ) );
2768                                         } else { // Get rid of the old restrictions
2769                                                 Title::purgeExpiredRestrictions();
2770                                                 $this->mTitleProtection = false;
2771                                         }
2772                                 } else {
2773                                         $this->mRestrictionsExpiry['create'] = $wgContLang->formatExpiry( '', TS_MW );
2774                                 }
2775                                 $this->mRestrictionsLoaded = true;
2776                         }
2777                 }
2778         }
2779
2780         /**
2781          * Flush the protection cache in this object and force reload from the database.
2782          * This is used when updating protection from WikiPage::doUpdateRestrictions().
2783          */
2784         public function flushRestrictions() {
2785                 $this->mRestrictionsLoaded = false;
2786                 $this->mTitleProtection = null;
2787         }
2788
2789         /**
2790          * Purge expired restrictions from the page_restrictions table
2791          */
2792         static function purgeExpiredRestrictions() {
2793                 if ( wfReadOnly() ) {
2794                         return;
2795                 }
2796
2797                 $dbw = wfGetDB( DB_MASTER );
2798                 $dbw->delete(
2799                         'page_restrictions',
2800                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2801                         __METHOD__
2802                 );
2803
2804                 $dbw->delete(
2805                         'protected_titles',
2806                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2807                         __METHOD__
2808                 );
2809         }
2810
2811         /**
2812          * Does this have subpages?  (Warning, usually requires an extra DB query.)
2813          *
2814          * @return Bool
2815          */
2816         public function hasSubpages() {
2817                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
2818                         # Duh
2819                         return false;
2820                 }
2821
2822                 # We dynamically add a member variable for the purpose of this method
2823                 # alone to cache the result.  There's no point in having it hanging
2824                 # around uninitialized in every Title object; therefore we only add it
2825                 # if needed and don't declare it statically.
2826                 if ( isset( $this->mHasSubpages ) ) {
2827                         return $this->mHasSubpages;
2828                 }
2829
2830                 $subpages = $this->getSubpages( 1 );
2831                 if ( $subpages instanceof TitleArray ) {
2832                         return $this->mHasSubpages = (bool)$subpages->count();
2833                 }
2834                 return $this->mHasSubpages = false;
2835         }
2836
2837         /**
2838          * Get all subpages of this page.
2839          *
2840          * @param $limit Int maximum number of subpages to fetch; -1 for no limit
2841          * @return mixed TitleArray, or empty array if this page's namespace
2842          *  doesn't allow subpages
2843          */
2844         public function getSubpages( $limit = -1 ) {
2845                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
2846                         return array();
2847                 }
2848
2849                 $dbr = wfGetDB( DB_SLAVE );
2850                 $conds['page_namespace'] = $this->getNamespace();
2851                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
2852                 $options = array();
2853                 if ( $limit > -1 ) {
2854                         $options['LIMIT'] = $limit;
2855                 }
2856                 return $this->mSubpages = TitleArray::newFromResult(
2857                         $dbr->select( 'page',
2858                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
2859                                 $conds,
2860                                 __METHOD__,
2861                                 $options
2862                         )
2863                 );
2864         }
2865
2866         /**
2867          * Is there a version of this page in the deletion archive?
2868          *
2869          * @return Int the number of archived revisions
2870          */
2871         public function isDeleted() {
2872                 if ( $this->getNamespace() < 0 ) {
2873                         $n = 0;
2874                 } else {
2875                         $dbr = wfGetDB( DB_SLAVE );
2876
2877                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2878                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2879                                 __METHOD__
2880                         );
2881                         if ( $this->getNamespace() == NS_FILE ) {
2882                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2883                                         array( 'fa_name' => $this->getDBkey() ),
2884                                         __METHOD__
2885                                 );
2886                         }
2887                 }
2888                 return (int)$n;
2889         }
2890
2891         /**
2892          * Is there a version of this page in the deletion archive?
2893          *
2894          * @return Boolean
2895          */
2896         public function isDeletedQuick() {
2897                 if ( $this->getNamespace() < 0 ) {
2898                         return false;
2899                 }
2900                 $dbr = wfGetDB( DB_SLAVE );
2901                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2902                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2903                         __METHOD__
2904                 );
2905                 if ( !$deleted && $this->getNamespace() == NS_FILE ) {
2906                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2907                                 array( 'fa_name' => $this->getDBkey() ),
2908                                 __METHOD__
2909                         );
2910                 }
2911                 return $deleted;
2912         }
2913
2914         /**
2915          * Get the article ID for this Title from the link cache,
2916          * adding it if necessary
2917          *
2918          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select
2919          *  for update
2920          * @return Int the ID
2921          */
2922         public function getArticleID( $flags = 0 ) {
2923                 if ( $this->getNamespace() < 0 ) {
2924                         return $this->mArticleID = 0;
2925                 }
2926                 $linkCache = LinkCache::singleton();
2927                 if ( $flags & self::GAID_FOR_UPDATE ) {
2928                         $oldUpdate = $linkCache->forUpdate( true );
2929                         $linkCache->clearLink( $this );
2930                         $this->mArticleID = $linkCache->addLinkObj( $this );
2931                         $linkCache->forUpdate( $oldUpdate );
2932                 } else {
2933                         if ( -1 == $this->mArticleID ) {
2934                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2935                         }
2936                 }
2937                 return $this->mArticleID;
2938         }
2939
2940         /**
2941          * Is this an article that is a redirect page?
2942          * Uses link cache, adding it if necessary
2943          *
2944          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2945          * @return Bool
2946          */
2947         public function isRedirect( $flags = 0 ) {
2948                 if ( !( $flags & Title::GAID_FOR_UPDATE ) && !is_null( $this->mRedirect ) ) {
2949                         return $this->mRedirect;
2950                 }
2951
2952                 if ( !$this->getArticleID( $flags ) ) {
2953                         return $this->mRedirect = false;
2954                 }
2955
2956                 $linkCache = LinkCache::singleton();
2957                 $linkCache->addLinkObj( $this );
2958                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2959
2960                 if ( $cached === null ) {
2961                         // Should not happen
2962                         throw new MWException( "LinkCache doesn't know redirect status of this title: " . $this->getPrefixedDBkey() );
2963                 }
2964
2965                 $this->mRedirect = (bool)$cached;
2966
2967                 return $this->mRedirect;
2968         }
2969
2970         /**
2971          * What is the length of this page?
2972          * Uses link cache, adding it if necessary
2973          *
2974          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2975          * @return Int
2976          */
2977         public function getLength( $flags = 0 ) {
2978                 if ( !( $flags & Title::GAID_FOR_UPDATE ) && $this->mLength != -1 ) {
2979                         return $this->mLength;
2980                 }
2981
2982                 if ( !$this->getArticleID( $flags ) ) {
2983                         return $this->mLength = 0;
2984                 }
2985
2986                 $linkCache = LinkCache::singleton();
2987                 $linkCache->addLinkObj( $this );
2988                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'length' );
2989
2990                 if ( $cached === null ) {
2991                         // Should not happen
2992                         throw new MWException( "LinkCache doesn't know redirect status of this title: " . $this->getPrefixedDBkey() );
2993                 }
2994
2995                 $this->mLength = intval( $cached );
2996
2997                 return $this->mLength;
2998         }
2999
3000         /**
3001          * What is the page_latest field for this page?
3002          *
3003          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
3004          * @throws MWException
3005          * @return Int or 0 if the page doesn't exist
3006          */
3007         public function getLatestRevID( $flags = 0 ) {
3008                 if ( !( $flags & Title::GAID_FOR_UPDATE ) && $this->mLatestID !== false ) {
3009                         return intval( $this->mLatestID );
3010                 }
3011
3012                 if ( !$this->getArticleID( $flags ) ) {
3013                         return $this->mLatestID = 0;
3014                 }
3015
3016                 $linkCache = LinkCache::singleton();
3017                 $linkCache->addLinkObj( $this );
3018                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'revision' );
3019
3020                 if ( $cached === null ) {
3021                         // Should not happen
3022                         throw new MWException( "LinkCache doesn't know latest revision ID of this title: " . $this->getPrefixedDBkey() );
3023                 }
3024
3025                 $this->mLatestID = intval( $cached );
3026
3027                 return $this->mLatestID;
3028         }
3029
3030         /**
3031          * This clears some fields in this object, and clears any associated
3032          * keys in the "bad links" section of the link cache.
3033          *
3034          * - This is called from WikiPage::doEdit() and WikiPage::insertOn() to allow
3035          * loading of the new page_id. It's also called from
3036          * WikiPage::doDeleteArticleReal()
3037          *
3038          * @param $newid Int the new Article ID
3039          */
3040         public function resetArticleID( $newid ) {
3041                 $linkCache = LinkCache::singleton();
3042                 $linkCache->clearLink( $this );
3043
3044                 if ( $newid === false ) {
3045                         $this->mArticleID = -1;
3046                 } else {
3047                         $this->mArticleID = intval( $newid );
3048                 }
3049                 $this->mRestrictionsLoaded = false;
3050                 $this->mRestrictions = array();
3051                 $this->mRedirect = null;
3052                 $this->mLength = -1;
3053                 $this->mLatestID = false;
3054                 $this->mContentModel = false;
3055                 $this->mEstimateRevisions = null;
3056         }
3057
3058         /**
3059          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
3060          *
3061          * @param $text String containing title to capitalize
3062          * @param $ns int namespace index, defaults to NS_MAIN
3063          * @return String containing capitalized title
3064          */
3065         public static function capitalize( $text, $ns = NS_MAIN ) {
3066                 global $wgContLang;
3067
3068                 if ( MWNamespace::isCapitalized( $ns ) ) {
3069                         return $wgContLang->ucfirst( $text );
3070                 } else {
3071                         return $text;
3072                 }
3073         }
3074
3075         /**
3076          * Secure and split - main initialisation function for this object
3077          *
3078          * Assumes that mDbkeyform has been set, and is urldecoded
3079          * and uses underscores, but not otherwise munged.  This function
3080          * removes illegal characters, splits off the interwiki and
3081          * namespace prefixes, sets the other forms, and canonicalizes
3082          * everything.
3083          *
3084          * @return Bool true on success
3085          */
3086         private function secureAndSplit() {
3087                 global $wgContLang, $wgLocalInterwiki;
3088
3089                 # Initialisation
3090                 $this->mInterwiki = $this->mFragment = '';
3091                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
3092
3093                 $dbkey = $this->mDbkeyform;
3094
3095                 # Strip Unicode bidi override characters.
3096                 # Sometimes they slip into cut-n-pasted page titles, where the
3097                 # override chars get included in list displays.
3098                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
3099
3100                 # Clean up whitespace
3101                 # Note: use of the /u option on preg_replace here will cause
3102                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
3103                 # conveniently disabling them.
3104                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
3105                 $dbkey = trim( $dbkey, '_' );
3106
3107                 if ( $dbkey == '' ) {
3108                         return false;
3109                 }
3110
3111                 if ( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
3112                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
3113                         return false;
3114                 }
3115
3116                 $this->mDbkeyform = $dbkey;
3117
3118                 # Initial colon indicates main namespace rather than specified default
3119                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
3120                 if ( ':' == $dbkey[0] ) {
3121                         $this->mNamespace = NS_MAIN;
3122                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
3123                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
3124                 }
3125
3126                 # Namespace or interwiki prefix
3127                 $firstPass = true;
3128                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
3129                 do {
3130                         $m = array();
3131                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
3132                                 $p = $m[1];
3133                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
3134                                         # Ordinary namespace
3135                                         $dbkey = $m[2];
3136                                         $this->mNamespace = $ns;
3137                                         # For Talk:X pages, check if X has a "namespace" prefix
3138                                         if ( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
3139                                                 if ( $wgContLang->getNsIndex( $x[1] ) ) {
3140                                                         # Disallow Talk:File:x type titles...
3141                                                         return false;
3142                                                 } elseif ( Interwiki::isValidInterwiki( $x[1] ) ) {
3143                                                         # Disallow Talk:Interwiki:x type titles...
3144                                                         return false;
3145                                                 }
3146                                         }
3147                                 } elseif ( Interwiki::isValidInterwiki( $p ) ) {
3148                                         if ( !$firstPass ) {
3149                                                 # Can't make a local interwiki link to an interwiki link.
3150                                                 # That's just crazy!
3151                                                 return false;
3152                                         }
3153
3154                                         # Interwiki link
3155                                         $dbkey = $m[2];
3156                                         $this->mInterwiki = $wgContLang->lc( $p );
3157
3158                                         # Redundant interwiki prefix to the local wiki
3159                                         if ( $wgLocalInterwiki !== false
3160                                                 && 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) )
3161                                         {
3162                                                 if ( $dbkey == '' ) {
3163                                                         # Can't have an empty self-link
3164                                                         return false;
3165                                                 }
3166                                                 $this->mInterwiki = '';
3167                                                 $firstPass = false;
3168                                                 # Do another namespace split...
3169                                                 continue;
3170                                         }
3171
3172                                         # If there's an initial colon after the interwiki, that also
3173                                         # resets the default namespace
3174                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
3175                                                 $this->mNamespace = NS_MAIN;
3176                                                 $dbkey = substr( $dbkey, 1 );
3177                                         }
3178                                 }
3179                                 # If there's no recognized interwiki or namespace,
3180                                 # then let the colon expression be part of the title.
3181                         }
3182                         break;
3183                 } while ( true );
3184
3185                 # We already know that some pages won't be in the database!
3186                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
3187                         $this->mArticleID = 0;
3188                 }
3189                 $fragment = strstr( $dbkey, '#' );
3190                 if ( false !== $fragment ) {
3191                         $this->setFragment( $fragment );
3192                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
3193                         # remove whitespace again: prevents "Foo_bar_#"
3194                         # becoming "Foo_bar_"
3195                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
3196                 }
3197
3198                 # Reject illegal characters.
3199                 $rxTc = self::getTitleInvalidRegex();
3200                 if ( preg_match( $rxTc, $dbkey ) ) {
3201                         return false;
3202                 }
3203
3204                 # Pages with "/./" or "/../" appearing in the URLs will often be un-
3205                 # reachable due to the way web browsers deal with 'relative' URLs.
3206                 # Also, they conflict with subpage syntax.  Forbid them explicitly.
3207                 if (
3208                         strpos( $dbkey, '.' ) !== false &&
3209                         (
3210                                 $dbkey === '.' || $dbkey === '..' ||
3211                                 strpos( $dbkey, './' ) === 0  ||
3212                                 strpos( $dbkey, '../' ) === 0 ||
3213                                 strpos( $dbkey, '/./' ) !== false ||
3214                                 strpos( $dbkey, '/../' ) !== false  ||
3215                                 substr( $dbkey, -2 ) == '/.' ||
3216                                 substr( $dbkey, -3 ) == '/..'
3217                         )
3218                 ) {
3219                         return false;
3220                 }
3221
3222                 # Magic tilde sequences? Nu-uh!
3223                 if ( strpos( $dbkey, '~~~' ) !== false ) {
3224                         return false;
3225                 }
3226
3227                 # Limit the size of titles to 255 bytes. This is typically the size of the
3228                 # underlying database field. We make an exception for special pages, which
3229                 # don't need to be stored in the database, and may edge over 255 bytes due
3230                 # to subpage syntax for long titles, e.g. [[Special:Block/Long name]]
3231                 if (
3232                         ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 )
3233                         || strlen( $dbkey ) > 512
3234                 ) {
3235                         return false;
3236                 }
3237
3238                 # Normally, all wiki links are forced to have an initial capital letter so [[foo]]
3239                 # and [[Foo]] point to the same place.  Don't force it for interwikis, since the
3240                 # other site might be case-sensitive.
3241                 $this->mUserCaseDBKey = $dbkey;
3242                 if ( $this->mInterwiki == '' ) {
3243                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
3244                 }
3245
3246                 # Can't make a link to a namespace alone... "empty" local links can only be
3247                 # self-links with a fragment identifier.
3248                 if ( $dbkey == '' && $this->mInterwiki == '' && $this->mNamespace != NS_MAIN ) {
3249                         return false;
3250                 }
3251
3252                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
3253                 // IP names are not allowed for accounts, and can only be referring to
3254                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
3255                 // there are numerous ways to present the same IP. Having sp:contribs scan
3256                 // them all is silly and having some show the edits and others not is
3257                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
3258                 $dbkey = ( $this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK )
3259                         ? IP::sanitizeIP( $dbkey )
3260                         : $dbkey;
3261
3262                 // Any remaining initial :s are illegal.
3263                 if ( $dbkey !== '' && ':' == $dbkey[0] ) {
3264                         return false;
3265                 }
3266
3267                 # Fill fields
3268                 $this->mDbkeyform = $dbkey;
3269                 $this->mUrlform = wfUrlencode( $dbkey );
3270
3271                 $this->mTextform = str_replace( '_', ' ', $dbkey );
3272
3273                 return true;
3274         }
3275
3276         /**
3277          * Get an array of Title objects linking to this Title
3278          * Also stores the IDs in the link cache.
3279          *
3280          * WARNING: do not use this function on arbitrary user-supplied titles!
3281          * On heavily-used templates it will max out the memory.
3282          *
3283          * @param $options Array: may be FOR UPDATE
3284          * @param $table String: table name
3285          * @param $prefix String: fields prefix
3286          * @return Array of Title objects linking here
3287          */
3288         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3289                 if ( count( $options ) > 0 ) {
3290                         $db = wfGetDB( DB_MASTER );
3291                 } else {
3292                         $db = wfGetDB( DB_SLAVE );
3293                 }
3294
3295                 $res = $db->select(
3296                         array( 'page', $table ),
3297                         self::getSelectFields(),
3298                         array(
3299                                 "{$prefix}_from=page_id",
3300                                 "{$prefix}_namespace" => $this->getNamespace(),
3301                                 "{$prefix}_title"     => $this->getDBkey() ),
3302                         __METHOD__,
3303                         $options
3304                 );
3305
3306                 $retVal = array();
3307                 if ( $res->numRows() ) {
3308                         $linkCache = LinkCache::singleton();
3309                         foreach ( $res as $row ) {
3310                                 $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title );
3311                                 if ( $titleObj ) {
3312                                         $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3313                                         $retVal[] = $titleObj;
3314                                 }
3315                         }
3316                 }
3317                 return $retVal;
3318         }
3319
3320         /**
3321          * Get an array of Title objects using this Title as a template
3322          * Also stores the IDs in the link cache.
3323          *
3324          * WARNING: do not use this function on arbitrary user-supplied titles!
3325          * On heavily-used templates it will max out the memory.
3326          *
3327          * @param $options Array: may be FOR UPDATE
3328          * @return Array of Title the Title objects linking here
3329          */
3330         public function getTemplateLinksTo( $options = array() ) {
3331                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
3332         }
3333
3334         /**
3335          * Get an array of Title objects linked from this Title
3336          * Also stores the IDs in the link cache.
3337          *
3338          * WARNING: do not use this function on arbitrary user-supplied titles!
3339          * On heavily-used templates it will max out the memory.
3340          *
3341          * @param $options Array: may be FOR UPDATE
3342          * @param $table String: table name
3343          * @param $prefix String: fields prefix
3344          * @return Array of Title objects linking here
3345          */
3346         public function getLinksFrom( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3347                 global $wgContentHandlerUseDB;
3348
3349                 $id = $this->getArticleID();
3350
3351                 # If the page doesn't exist; there can't be any link from this page
3352                 if ( !$id ) {
3353                         return array();
3354                 }
3355
3356                 if ( count( $options ) > 0 ) {
3357                         $db = wfGetDB( DB_MASTER );
3358                 } else {
3359                         $db = wfGetDB( DB_SLAVE );
3360                 }
3361
3362                 $namespaceFiled = "{$prefix}_namespace";
3363                 $titleField = "{$prefix}_title";
3364
3365                 $fields = array( $namespaceFiled, $titleField, 'page_id', 'page_len', 'page_is_redirect', 'page_latest' );
3366                 if ( $wgContentHandlerUseDB ) $fields[] = 'page_content_model';
3367
3368                 $res = $db->select(
3369                         array( $table, 'page' ),
3370                         $fields,
3371                         array( "{$prefix}_from" => $id ),
3372                         __METHOD__,
3373                         $options,
3374                         array( 'page' => array( 'LEFT JOIN', array( "page_namespace=$namespaceFiled", "page_title=$titleField" ) ) )
3375                 );
3376
3377                 $retVal = array();
3378                 if ( $res->numRows() ) {
3379                         $linkCache = LinkCache::singleton();
3380                         foreach ( $res as $row ) {
3381                                 $titleObj = Title::makeTitle( $row->$namespaceFiled, $row->$titleField );
3382                                 if ( $titleObj ) {
3383                                         if ( $row->page_id ) {
3384                                                 $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3385                                         } else {
3386                                                 $linkCache->addBadLinkObj( $titleObj );
3387                                         }
3388                                         $retVal[] = $titleObj;
3389                                 }
3390                         }
3391                 }
3392                 return $retVal;
3393         }
3394
3395         /**
3396          * Get an array of Title objects used on this Title as a template
3397          * Also stores the IDs in the link cache.
3398          *
3399          * WARNING: do not use this function on arbitrary user-supplied titles!
3400          * On heavily-used templates it will max out the memory.
3401          *
3402          * @param $options Array: may be FOR UPDATE
3403          * @return Array of Title the Title objects used here
3404          */
3405         public function getTemplateLinksFrom( $options = array() ) {
3406                 return $this->getLinksFrom( $options, 'templatelinks', 'tl' );
3407         }
3408
3409         /**
3410          * Get an array of Title objects referring to non-existent articles linked from this page
3411          *
3412          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
3413          * @return Array of Title the Title objects
3414          */
3415         public function getBrokenLinksFrom() {
3416                 if ( $this->getArticleID() == 0 ) {
3417                         # All links from article ID 0 are false positives
3418                         return array();
3419                 }
3420
3421                 $dbr = wfGetDB( DB_SLAVE );
3422                 $res = $dbr->select(
3423                         array( 'page', 'pagelinks' ),
3424                         array( 'pl_namespace', 'pl_title' ),
3425                         array(
3426                                 'pl_from' => $this->getArticleID(),
3427                                 'page_namespace IS NULL'
3428                         ),
3429                         __METHOD__, array(),
3430                         array(
3431                                 'page' => array(
3432                                         'LEFT JOIN',
3433                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
3434                                 )
3435                         )
3436                 );
3437
3438                 $retVal = array();
3439                 foreach ( $res as $row ) {
3440                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
3441                 }
3442                 return $retVal;
3443         }
3444
3445
3446         /**
3447          * Get a list of URLs to purge from the Squid cache when this
3448          * page changes
3449          *
3450          * @return Array of String the URLs
3451          */
3452         public function getSquidURLs() {
3453                 $urls = array(
3454                         $this->getInternalURL(),
3455                         $this->getInternalURL( 'action=history' )
3456                 );
3457
3458                 $pageLang = $this->getPageLanguage();
3459                 if ( $pageLang->hasVariants() ) {
3460                         $variants = $pageLang->getVariants();
3461                         foreach ( $variants as $vCode ) {
3462                                 $urls[] = $this->getInternalURL( '', $vCode );
3463                         }
3464                 }
3465
3466                 return $urls;
3467         }
3468
3469         /**
3470          * Purge all applicable Squid URLs
3471          */
3472         public function purgeSquid() {
3473                 global $wgUseSquid;
3474                 if ( $wgUseSquid ) {
3475                         $urls = $this->getSquidURLs();
3476                         $u = new SquidUpdate( $urls );
3477                         $u->doUpdate();
3478                 }
3479         }
3480
3481         /**
3482          * Move this page without authentication
3483          *
3484          * @param $nt Title the new page Title
3485          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3486          */
3487         public function moveNoAuth( &$nt ) {
3488                 return $this->moveTo( $nt, false );
3489         }
3490
3491         /**
3492          * Check whether a given move operation would be valid.
3493          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
3494          *
3495          * @param $nt Title the new title
3496          * @param $auth Bool indicates whether $wgUser's permissions
3497          *  should be checked
3498          * @param $reason String is the log summary of the move, used for spam checking
3499          * @return Mixed True on success, getUserPermissionsErrors()-like array on failure
3500          */
3501         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
3502                 global $wgUser, $wgContentHandlerUseDB;
3503
3504                 $errors = array();
3505                 if ( !$nt ) {
3506                         // Normally we'd add this to $errors, but we'll get
3507                         // lots of syntax errors if $nt is not an object
3508                         return array( array( 'badtitletext' ) );
3509                 }
3510                 if ( $this->equals( $nt ) ) {
3511                         $errors[] = array( 'selfmove' );
3512                 }
3513                 if ( !$this->isMovable() ) {
3514                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
3515                 }
3516                 if ( $nt->getInterwiki() != '' ) {
3517                         $errors[] = array( 'immobile-target-namespace-iw' );
3518                 }
3519                 if ( !$nt->isMovable() ) {
3520                         $errors[] = array( 'immobile-target-namespace', $nt->getNsText() );
3521                 }
3522
3523                 $oldid = $this->getArticleID();
3524                 $newid = $nt->getArticleID();
3525
3526                 if ( strlen( $nt->getDBkey() ) < 1 ) {
3527                         $errors[] = array( 'articleexists' );
3528                 }
3529                 if (
3530                         ( $this->getDBkey() == '' ) ||
3531                         ( !$oldid ) ||
3532                         ( $nt->getDBkey() == '' )
3533                 ) {
3534                         $errors[] = array( 'badarticleerror' );
3535                 }
3536
3537                 // Content model checks
3538                 if ( !$wgContentHandlerUseDB &&
3539                                 $this->getContentModel() !== $nt->getContentModel() ) {
3540                         // can't move a page if that would change the page's content model
3541                         $errors[] = array(
3542                                 'bad-target-model',
3543                                 ContentHandler::getLocalizedName( $this->getContentModel() ),
3544                                 ContentHandler::getLocalizedName( $nt->getContentModel() )
3545                         );
3546                 }
3547
3548                 // Image-specific checks
3549                 if ( $this->getNamespace() == NS_FILE ) {
3550                         $errors = array_merge( $errors, $this->validateFileMoveOperation( $nt ) );
3551                 }
3552
3553                 if ( $nt->getNamespace() == NS_FILE && $this->getNamespace() != NS_FILE ) {
3554                         $errors[] = array( 'nonfile-cannot-move-to-file' );
3555                 }
3556
3557                 if ( $auth ) {
3558                         $errors = wfMergeErrorArrays( $errors,
3559                                 $this->getUserPermissionsErrors( 'move', $wgUser ),
3560                                 $this->getUserPermissionsErrors( 'edit', $wgUser ),
3561                                 $nt->getUserPermissionsErrors( 'move-target', $wgUser ),
3562                                 $nt->getUserPermissionsErrors( 'edit', $wgUser ) );
3563                 }
3564
3565                 $match = EditPage::matchSummarySpamRegex( $reason );
3566                 if ( $match !== false ) {
3567                         // This is kind of lame, won't display nice
3568                         $errors[] = array( 'spamprotectiontext' );
3569                 }
3570
3571                 $err = null;
3572                 if ( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
3573                         $errors[] = array( 'hookaborted', $err );
3574                 }
3575
3576                 # The move is allowed only if (1) the target doesn't exist, or
3577                 # (2) the target is a redirect to the source, and has no history
3578                 # (so we can undo bad moves right after they're done).
3579
3580                 if ( 0 != $newid ) { # Target exists; check for validity
3581                         if ( !$this->isValidMoveTarget( $nt ) ) {
3582                                 $errors[] = array( 'articleexists' );
3583                         }
3584                 } else {
3585                         $tp = $nt->getTitleProtection();
3586                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
3587                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
3588                                 $errors[] = array( 'cantmove-titleprotected' );
3589                         }
3590                 }
3591                 if ( empty( $errors ) ) {
3592                         return true;
3593                 }
3594                 return $errors;
3595         }
3596
3597         /**
3598          * Check if the requested move target is a valid file move target
3599          * @param Title $nt Target title
3600          * @return array List of errors
3601          */
3602         protected function validateFileMoveOperation( $nt ) {
3603                 global $wgUser;
3604
3605                 $errors = array();
3606
3607                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is not allowed until below
3608
3609                 $file = wfLocalFile( $this );
3610                 if ( $file->exists() ) {
3611                         if ( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
3612                                 $errors[] = array( 'imageinvalidfilename' );
3613                         }
3614                         if ( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
3615                                 $errors[] = array( 'imagetypemismatch' );
3616                         }
3617                 }
3618
3619                 if ( $nt->getNamespace() != NS_FILE ) {
3620                         $errors[] = array( 'imagenocrossnamespace' );
3621                         // From here we want to do checks on a file object, so if we can't
3622                         // create one, we must return.
3623                         return $errors;
3624                 }
3625
3626                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is allowed below here
3627
3628                 $destFile = wfLocalFile( $nt );
3629                 if ( !$wgUser->isAllowed( 'reupload-shared' ) && !$destFile->exists() && wfFindFile( $nt ) ) {
3630                         $errors[] = array( 'file-exists-sharedrepo' );
3631                 }
3632
3633                 return $errors;
3634         }
3635
3636         /**
3637          * Move a title to a new location
3638          *
3639          * @param $nt Title the new title
3640          * @param $auth Bool indicates whether $wgUser's permissions
3641          *  should be checked
3642          * @param $reason String the reason for the move
3643          * @param $createRedirect Bool Whether to create a redirect from the old title to the new title.
3644          *  Ignored if the user doesn't have the suppressredirect right.
3645          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3646          */
3647         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
3648                 global $wgUser;
3649                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
3650                 if ( is_array( $err ) ) {
3651                         // Auto-block user's IP if the account was "hard" blocked
3652                         $wgUser->spreadAnyEditBlock();
3653                         return $err;
3654                 }
3655                 // Check suppressredirect permission
3656                 if ( $auth && !$wgUser->isAllowed( 'suppressredirect' ) ) {
3657                         $createRedirect = true;
3658                 }
3659
3660                 // If it is a file, move it first.
3661                 // It is done before all other moving stuff is done because it's hard to revert.
3662                 $dbw = wfGetDB( DB_MASTER );
3663                 if ( $this->getNamespace() == NS_FILE ) {
3664                         $file = wfLocalFile( $this );
3665                         if ( $file->exists() ) {
3666                                 $status = $file->move( $nt );
3667                                 if ( !$status->isOk() ) {
3668                                         return $status->getErrorsArray();
3669                                 }
3670                         }
3671                         // Clear RepoGroup process cache
3672                         RepoGroup::singleton()->clearCache( $this );
3673                         RepoGroup::singleton()->clearCache( $nt ); # clear false negative cache
3674                 }
3675
3676                 $dbw->begin( __METHOD__ ); # If $file was a LocalFile, its transaction would have closed our own.
3677                 $pageid = $this->getArticleID( self::GAID_FOR_UPDATE );
3678                 $protected = $this->isProtected();
3679
3680                 // Do the actual move
3681                 $this->moveToInternal( $nt, $reason, $createRedirect );
3682
3683                 // Refresh the sortkey for this row.  Be careful to avoid resetting
3684                 // cl_timestamp, which may disturb time-based lists on some sites.
3685                 $prefixes = $dbw->select(
3686                         'categorylinks',
3687                         array( 'cl_sortkey_prefix', 'cl_to' ),
3688                         array( 'cl_from' => $pageid ),
3689                         __METHOD__
3690                 );
3691                 foreach ( $prefixes as $prefixRow ) {
3692                         $prefix = $prefixRow->cl_sortkey_prefix;
3693                         $catTo = $prefixRow->cl_to;
3694                         $dbw->update( 'categorylinks',
3695                                 array(
3696                                         'cl_sortkey' => Collation::singleton()->getSortKey(
3697                                                 $nt->getCategorySortkey( $prefix ) ),
3698                                         'cl_timestamp=cl_timestamp' ),
3699                                 array(
3700                                         'cl_from' => $pageid,
3701                                         'cl_to' => $catTo ),
3702                                 __METHOD__
3703                         );
3704                 }
3705
3706                 $redirid = $this->getArticleID();
3707
3708                 if ( $protected ) {
3709                         # Protect the redirect title as the title used to be...
3710                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
3711                                 array(
3712                                         'pr_page'    => $redirid,
3713                                         'pr_type'    => 'pr_type',
3714                                         'pr_level'   => 'pr_level',
3715                                         'pr_cascade' => 'pr_cascade',
3716                                         'pr_user'    => 'pr_user',
3717                                         'pr_expiry'  => 'pr_expiry'
3718                                 ),
3719                                 array( 'pr_page' => $pageid ),
3720                                 __METHOD__,
3721                                 array( 'IGNORE' )
3722                         );
3723                         # Update the protection log
3724                         $log = new LogPage( 'protect' );
3725                         $comment = wfMessage(
3726                                 'prot_1movedto2',
3727                                 $this->getPrefixedText(),
3728                                 $nt->getPrefixedText()
3729                         )->inContentLanguage()->text();
3730                         if ( $reason ) {
3731                                 $comment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
3732                         }
3733                         // @todo FIXME: $params?
3734                         $log->addEntry( 'move_prot', $nt, $comment, array( $this->getPrefixedText() ) );
3735                 }
3736
3737                 # Update watchlists
3738                 $oldnamespace = MWNamespace::getSubject( $this->getNamespace() );
3739                 $newnamespace = MWNamespace::getSubject( $nt->getNamespace() );
3740                 $oldtitle = $this->getDBkey();
3741                 $newtitle = $nt->getDBkey();
3742
3743                 if ( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
3744                         WatchedItem::duplicateEntries( $this, $nt );
3745                 }
3746
3747                 $dbw->commit( __METHOD__ );
3748
3749                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3750                 return true;
3751         }
3752
3753         /**
3754          * Move page to a title which is either a redirect to the
3755          * source page or nonexistent
3756          *
3757          * @param $nt Title the page to move to, which should be a redirect or nonexistent
3758          * @param $reason String The reason for the move
3759          * @param $createRedirect Bool Whether to leave a redirect at the old title. Does not check
3760          *   if the user has the suppressredirect right
3761          * @throws MWException
3762          */
3763         private function moveToInternal( &$nt, $reason = '', $createRedirect = true ) {
3764                 global $wgUser, $wgContLang;
3765
3766                 if ( $nt->exists() ) {
3767                         $moveOverRedirect = true;
3768                         $logType = 'move_redir';
3769                 } else {
3770                         $moveOverRedirect = false;
3771                         $logType = 'move';
3772                 }
3773
3774                 if ( $createRedirect ) {
3775                         $contentHandler = ContentHandler::getForTitle( $this );
3776                         $redirectContent = $contentHandler->makeRedirectContent( $nt );
3777
3778                         // NOTE: If this page's content model does not support redirects, $redirectContent will be null.
3779                 } else {
3780                         $redirectContent = null;
3781                 }
3782
3783                 $logEntry = new ManualLogEntry( 'move', $logType );
3784                 $logEntry->setPerformer( $wgUser );
3785                 $logEntry->setTarget( $this );
3786                 $logEntry->setComment( $reason );
3787                 $logEntry->setParameters( array(
3788                         '4::target' => $nt->getPrefixedText(),
3789                         '5::noredir' => $redirectContent ? '0': '1',
3790                 ) );
3791
3792                 $formatter = LogFormatter::newFromEntry( $logEntry );
3793                 $formatter->setContext( RequestContext::newExtraneousContext( $this ) );
3794                 $comment = $formatter->getPlainActionText();
3795                 if ( $reason ) {
3796                         $comment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
3797                 }
3798                 # Truncate for whole multibyte characters.
3799                 $comment = $wgContLang->truncate( $comment, 255 );
3800
3801                 $oldid = $this->getArticleID();
3802
3803                 $dbw = wfGetDB( DB_MASTER );
3804
3805                 $newpage = WikiPage::factory( $nt );
3806
3807                 if ( $moveOverRedirect ) {
3808                         $newid = $nt->getArticleID();
3809
3810                         # Delete the old redirect. We don't save it to history since
3811                         # by definition if we've got here it's rather uninteresting.
3812                         # We have to remove it so that the next step doesn't trigger
3813                         # a conflict on the unique namespace+title index...
3814                         $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3815
3816                         $newpage->doDeleteUpdates( $newid );
3817                 }
3818
3819                 # Save a null revision in the page's history notifying of the move
3820                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3821                 if ( !is_object( $nullRevision ) ) {
3822                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3823                 }
3824
3825                 $nullRevision->insertOn( $dbw );
3826
3827                 # Change the name of the target page:
3828                 $dbw->update( 'page',
3829                         /* SET */ array(
3830                                 'page_namespace' => $nt->getNamespace(),
3831                                 'page_title'     => $nt->getDBkey(),
3832                         ),
3833                         /* WHERE */ array( 'page_id' => $oldid ),
3834                         __METHOD__
3835                 );
3836
3837                 $this->resetArticleID( 0 );
3838                 $nt->resetArticleID( $oldid );
3839
3840                 $newpage->updateRevisionOn( $dbw, $nullRevision );
3841
3842                 wfRunHooks( 'NewRevisionFromEditComplete',
3843                         array( $newpage, $nullRevision, $nullRevision->getParentId(), $wgUser ) );
3844
3845                 $newpage->doEditUpdates( $nullRevision, $wgUser, array( 'changed' => false ) );
3846
3847                 if ( !$moveOverRedirect ) {
3848                         WikiPage::onArticleCreate( $nt );
3849                 }
3850
3851                 # Recreate the redirect, this time in the other direction.
3852                 if ( !$redirectContent ) {
3853                         WikiPage::onArticleDelete( $this );
3854                 } else {
3855                         $redirectArticle = WikiPage::factory( $this );
3856                         $newid = $redirectArticle->insertOn( $dbw );
3857                         if ( $newid ) { // sanity
3858                                 $redirectRevision = new Revision( array(
3859                                         'title'   => $this, // for determining the default content model
3860                                         'page'    => $newid,
3861                                         'comment' => $comment,
3862                                         'content'    => $redirectContent ) );
3863                                 $redirectRevision->insertOn( $dbw );
3864                                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3865
3866                                 wfRunHooks( 'NewRevisionFromEditComplete',
3867                                         array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3868
3869                                 $redirectArticle->doEditUpdates( $redirectRevision, $wgUser, array( 'created' => true ) );
3870                         }
3871                 }
3872
3873                 # Log the move
3874                 $logid = $logEntry->insert();
3875                 $logEntry->publish( $logid );
3876         }
3877
3878         /**
3879          * Move this page's subpages to be subpages of $nt
3880          *
3881          * @param $nt Title Move target
3882          * @param $auth bool Whether $wgUser's permissions should be checked
3883          * @param $reason string The reason for the move
3884          * @param $createRedirect bool Whether to create redirects from the old subpages to
3885          *     the new ones Ignored if the user doesn't have the 'suppressredirect' right
3886          * @return mixed array with old page titles as keys, and strings (new page titles) or
3887          *     arrays (errors) as values, or an error array with numeric indices if no pages
3888          *     were moved
3889          */
3890         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3891                 global $wgMaximumMovedPages;
3892                 // Check permissions
3893                 if ( !$this->userCan( 'move-subpages' ) ) {
3894                         return array( 'cant-move-subpages' );
3895                 }
3896                 // Do the source and target namespaces support subpages?
3897                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
3898                         return array( 'namespace-nosubpages',
3899                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3900                 }
3901                 if ( !MWNamespace::hasSubpages( $nt->getNamespace() ) ) {
3902                         return array( 'namespace-nosubpages',
3903                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3904                 }
3905
3906                 $subpages = $this->getSubpages( $wgMaximumMovedPages + 1 );
3907                 $retval = array();
3908                 $count = 0;
3909                 foreach ( $subpages as $oldSubpage ) {
3910                         $count++;
3911                         if ( $count > $wgMaximumMovedPages ) {
3912                                 $retval[$oldSubpage->getPrefixedTitle()] =
3913                                                 array( 'movepage-max-pages',
3914                                                         $wgMaximumMovedPages );
3915                                 break;
3916                         }
3917
3918                         // We don't know whether this function was called before
3919                         // or after moving the root page, so check both
3920                         // $this and $nt
3921                         if ( $oldSubpage->getArticleID() == $this->getArticleID() ||
3922                                         $oldSubpage->getArticleID() == $nt->getArticleID() )
3923                         {
3924                                 // When moving a page to a subpage of itself,
3925                                 // don't move it twice
3926                                 continue;
3927                         }
3928                         $newPageName = preg_replace(
3929                                         '#^' . preg_quote( $this->getDBkey(), '#' ) . '#',
3930                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3931                                         $oldSubpage->getDBkey() );
3932                         if ( $oldSubpage->isTalkPage() ) {
3933                                 $newNs = $nt->getTalkPage()->getNamespace();
3934                         } else {
3935                                 $newNs = $nt->getSubjectPage()->getNamespace();
3936                         }
3937                         # Bug 14385: we need makeTitleSafe because the new page names may
3938                         # be longer than 255 characters.
3939                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3940
3941                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3942                         if ( $success === true ) {
3943                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3944                         } else {
3945                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3946                         }
3947                 }
3948                 return $retval;
3949         }
3950
3951         /**
3952          * Checks if this page is just a one-rev redirect.
3953          * Adds lock, so don't use just for light purposes.
3954          *
3955          * @return Bool
3956          */
3957         public function isSingleRevRedirect() {
3958                 global $wgContentHandlerUseDB;
3959
3960                 $dbw = wfGetDB( DB_MASTER );
3961
3962                 # Is it a redirect?
3963                 $fields = array( 'page_is_redirect', 'page_latest', 'page_id' );
3964                 if ( $wgContentHandlerUseDB ) $fields[] = 'page_content_model';
3965
3966                 $row = $dbw->selectRow( 'page',
3967                         $fields,
3968                         $this->pageCond(),
3969                         __METHOD__,
3970                         array( 'FOR UPDATE' )
3971                 );
3972                 # Cache some fields we may want
3973                 $this->mArticleID = $row ? intval( $row->page_id ) : 0;
3974                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3975                 $this->mLatestID = $row ? intval( $row->page_latest ) : false;
3976                 $this->mContentModel = $row && isset( $row->page_content_model ) ? strval( $row->page_content_model ) : false;
3977                 if ( !$this->mRedirect ) {
3978                         return false;
3979                 }
3980                 # Does the article have a history?
3981                 $row = $dbw->selectField( array( 'page', 'revision' ),
3982                         'rev_id',
3983                         array( 'page_namespace' => $this->getNamespace(),
3984                                 'page_title' => $this->getDBkey(),
3985                                 'page_id=rev_page',
3986                                 'page_latest != rev_id'
3987                         ),
3988                         __METHOD__,
3989                         array( 'FOR UPDATE' )
3990                 );
3991                 # Return true if there was no history
3992                 return ( $row === false );
3993         }
3994
3995         /**
3996          * Checks if $this can be moved to a given Title
3997          * - Selects for update, so don't call it unless you mean business
3998          *
3999          * @param $nt Title the new title to check
4000          * @return Bool
4001          */
4002         public function isValidMoveTarget( $nt ) {
4003                 # Is it an existing file?
4004                 if ( $nt->getNamespace() == NS_FILE ) {
4005                         $file = wfLocalFile( $nt );
4006                         if ( $file->exists() ) {
4007                                 wfDebug( __METHOD__ . ": file exists\n" );
4008                                 return false;
4009                         }
4010                 }
4011                 # Is it a redirect with no history?
4012                 if ( !$nt->isSingleRevRedirect() ) {
4013                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
4014                         return false;
4015                 }
4016                 # Get the article text
4017                 $rev = Revision::newFromTitle( $nt, false, Revision::READ_LATEST );
4018                 if( !is_object( $rev ) ) {
4019                         return false;
4020                 }
4021                 $content = $rev->getContent();
4022                 # Does the redirect point to the source?
4023                 # Or is it a broken self-redirect, usually caused by namespace collisions?
4024                 $redirTitle = $content ? $content->getRedirectTarget() : null;
4025
4026                 if ( $redirTitle ) {
4027                         if ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
4028                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) {
4029                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
4030                                 return false;
4031                         } else {
4032                                 return true;
4033                         }
4034                 } else {
4035                         # Fail safe (not a redirect after all. strange.)
4036                         wfDebug( __METHOD__ . ": failsafe: database sais " . $nt->getPrefixedDBkey() .
4037                                                 " is a redirect, but it doesn't contain a valid redirect.\n" );
4038                         return false;
4039                 }
4040         }
4041
4042         /**
4043          * Get categories to which this Title belongs and return an array of
4044          * categories' names.
4045          *
4046          * @return Array of parents in the form:
4047          *        $parent => $currentarticle
4048          */
4049         public function getParentCategories() {
4050                 global $wgContLang;
4051
4052                 $data = array();
4053
4054                 $titleKey = $this->getArticleID();
4055
4056                 if ( $titleKey === 0 ) {
4057                         return $data;
4058                 }
4059
4060                 $dbr = wfGetDB( DB_SLAVE );
4061
4062                 $res = $dbr->select(
4063                         'categorylinks',
4064                         'cl_to',
4065                         array( 'cl_from' => $titleKey ),
4066                         __METHOD__
4067                 );
4068
4069                 if ( $res->numRows() > 0 ) {
4070                         foreach ( $res as $row ) {
4071                                 // $data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
4072                                 $data[$wgContLang->getNSText( NS_CATEGORY ) . ':' . $row->cl_to] = $this->getFullText();
4073                         }
4074                 }
4075                 return $data;
4076         }
4077
4078         /**
4079          * Get a tree of parent categories
4080          *
4081          * @param $children Array with the children in the keys, to check for circular refs
4082          * @return Array Tree of parent categories
4083          */
4084         public function getParentCategoryTree( $children = array() ) {
4085                 $stack = array();
4086                 $parents = $this->getParentCategories();
4087
4088                 if ( $parents ) {
4089                         foreach ( $parents as $parent => $current ) {
4090                                 if ( array_key_exists( $parent, $children ) ) {
4091                                         # Circular reference
4092                                         $stack[$parent] = array();
4093                                 } else {
4094                                         $nt = Title::newFromText( $parent );
4095                                         if ( $nt ) {
4096                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array( $parent => 1 ) );
4097                                         }
4098                                 }
4099                         }
4100                 }
4101
4102                 return $stack;
4103         }
4104
4105         /**
4106          * Get an associative array for selecting this title from
4107          * the "page" table
4108          *
4109          * @return Array suitable for the $where parameter of DB::select()
4110          */
4111         public function pageCond() {
4112                 if ( $this->mArticleID > 0 ) {
4113                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
4114                         return array( 'page_id' => $this->mArticleID );
4115                 } else {
4116                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
4117                 }
4118         }
4119
4120         /**
4121          * Get the revision ID of the previous revision
4122          *
4123          * @param $revId Int Revision ID. Get the revision that was before this one.
4124          * @param $flags Int Title::GAID_FOR_UPDATE
4125          * @return Int|Bool Old revision ID, or FALSE if none exists
4126          */
4127         public function getPreviousRevisionID( $revId, $flags = 0 ) {
4128                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4129                 $revId = $db->selectField( 'revision', 'rev_id',
4130                         array(
4131                                 'rev_page' => $this->getArticleID( $flags ),
4132                                 'rev_id < ' . intval( $revId )
4133                         ),
4134                         __METHOD__,
4135                         array( 'ORDER BY' => 'rev_id DESC' )
4136                 );
4137
4138                 if ( $revId === false ) {
4139                         return false;
4140                 } else {
4141                         return intval( $revId );
4142                 }
4143         }
4144
4145         /**
4146          * Get the revision ID of the next revision
4147          *
4148          * @param $revId Int Revision ID. Get the revision that was after this one.
4149          * @param $flags Int Title::GAID_FOR_UPDATE
4150          * @return Int|Bool Next revision ID, or FALSE if none exists
4151          */
4152         public function getNextRevisionID( $revId, $flags = 0 ) {
4153                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4154                 $revId = $db->selectField( 'revision', 'rev_id',
4155                         array(
4156                                 'rev_page' => $this->getArticleID( $flags ),
4157                                 'rev_id > ' . intval( $revId )
4158                         ),
4159                         __METHOD__,
4160                         array( 'ORDER BY' => 'rev_id' )
4161                 );
4162
4163                 if ( $revId === false ) {
4164                         return false;
4165                 } else {
4166                         return intval( $revId );
4167                 }
4168         }
4169
4170         /**
4171          * Get the first revision of the page
4172          *
4173          * @param $flags Int Title::GAID_FOR_UPDATE
4174          * @return Revision|Null if page doesn't exist
4175          */
4176         public function getFirstRevision( $flags = 0 ) {
4177                 $pageId = $this->getArticleID( $flags );
4178                 if ( $pageId ) {
4179                         $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4180                         $row = $db->selectRow( 'revision', Revision::selectFields(),
4181                                 array( 'rev_page' => $pageId ),
4182                                 __METHOD__,
4183                                 array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
4184                         );
4185                         if ( $row ) {
4186                                 return new Revision( $row );
4187                         }
4188                 }
4189                 return null;
4190         }
4191
4192         /**
4193          * Get the oldest revision timestamp of this page
4194          *
4195          * @param $flags Int Title::GAID_FOR_UPDATE
4196          * @return String: MW timestamp
4197          */
4198         public function getEarliestRevTime( $flags = 0 ) {
4199                 $rev = $this->getFirstRevision( $flags );
4200                 return $rev ? $rev->getTimestamp() : null;
4201         }
4202
4203         /**
4204          * Check if this is a new page
4205          *
4206          * @return bool
4207          */
4208         public function isNewPage() {
4209                 $dbr = wfGetDB( DB_SLAVE );
4210                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
4211         }
4212
4213         /**
4214          * Check whether the number of revisions of this page surpasses $wgDeleteRevisionsLimit
4215          *
4216          * @return bool
4217          */
4218         public function isBigDeletion() {
4219                 global $wgDeleteRevisionsLimit;
4220
4221                 if ( !$wgDeleteRevisionsLimit ) {
4222                         return false;
4223                 }
4224
4225                 $revCount = $this->estimateRevisionCount();
4226                 return $revCount > $wgDeleteRevisionsLimit;
4227         }
4228
4229         /**
4230          * Get the  approximate revision count of this page.
4231          *
4232          * @return int
4233          */
4234         public function estimateRevisionCount() {
4235                 if ( !$this->exists() ) {
4236                         return 0;
4237                 }
4238
4239                 if ( $this->mEstimateRevisions === null ) {
4240                         $dbr = wfGetDB( DB_SLAVE );
4241                         $this->mEstimateRevisions = $dbr->estimateRowCount( 'revision', '*',
4242                                 array( 'rev_page' => $this->getArticleID() ), __METHOD__ );
4243                 }
4244
4245                 return $this->mEstimateRevisions;
4246         }
4247
4248         /**
4249          * Get the number of revisions between the given revision.
4250          * Used for diffs and other things that really need it.
4251          *
4252          * @param $old int|Revision Old revision or rev ID (first before range)
4253          * @param $new int|Revision New revision or rev ID (first after range)
4254          * @return Int Number of revisions between these revisions.
4255          */
4256         public function countRevisionsBetween( $old, $new ) {
4257                 if ( !( $old instanceof Revision ) ) {
4258                         $old = Revision::newFromTitle( $this, (int)$old );
4259                 }
4260                 if ( !( $new instanceof Revision ) ) {
4261                         $new = Revision::newFromTitle( $this, (int)$new );
4262                 }
4263                 if ( !$old || !$new ) {
4264                         return 0; // nothing to compare
4265                 }
4266                 $dbr = wfGetDB( DB_SLAVE );
4267                 return (int)$dbr->selectField( 'revision', 'count(*)',
4268                         array(
4269                                 'rev_page' => $this->getArticleID(),
4270                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4271                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4272                         ),
4273                         __METHOD__
4274                 );
4275         }
4276
4277         /**
4278          * Get the number of authors between the given revisions or revision IDs.
4279          * Used for diffs and other things that really need it.
4280          *
4281          * @param $old int|Revision Old revision or rev ID (first before range by default)
4282          * @param $new int|Revision New revision or rev ID (first after range by default)
4283          * @param $limit int Maximum number of authors
4284          * @param $options string|array (Optional): Single option, or an array of options:
4285          *     'include_old' Include $old in the range; $new is excluded.
4286          *     'include_new' Include $new in the range; $old is excluded.
4287          *     'include_both' Include both $old and $new in the range.
4288          *     Unknown option values are ignored.
4289          * @return int Number of revision authors in the range; zero if not both revisions exist
4290          */
4291         public function countAuthorsBetween( $old, $new, $limit, $options = array() ) {
4292                 if ( !( $old instanceof Revision ) ) {
4293                         $old = Revision::newFromTitle( $this, (int)$old );
4294                 }
4295                 if ( !( $new instanceof Revision ) ) {
4296                         $new = Revision::newFromTitle( $this, (int)$new );
4297                 }
4298                 // XXX: what if Revision objects are passed in, but they don't refer to this title?
4299                 // Add $old->getPage() != $new->getPage() || $old->getPage() != $this->getArticleID()
4300                 // in the sanity check below?
4301                 if ( !$old || !$new ) {
4302                         return 0; // nothing to compare
4303                 }
4304                 $old_cmp = '>';
4305                 $new_cmp = '<';
4306                 $options = (array)$options;
4307                 if ( in_array( 'include_old', $options ) ) {
4308                         $old_cmp = '>=';
4309                 }
4310                 if ( in_array( 'include_new', $options ) ) {
4311                         $new_cmp = '<=';
4312                 }
4313                 if ( in_array( 'include_both', $options ) ) {
4314                         $old_cmp = '>=';
4315                         $new_cmp = '<=';
4316                 }
4317                 // No DB query needed if $old and $new are the same or successive revisions:
4318                 if ( $old->getId() === $new->getId() ) {
4319                         return ( $old_cmp === '>' && $new_cmp === '<' ) ? 0 : 1;
4320                 } else if ( $old->getId() === $new->getParentId() ) {
4321                         if ( $old_cmp === '>' || $new_cmp === '<' ) {
4322                                 return ( $old_cmp === '>' && $new_cmp === '<' ) ? 0 : 1;
4323                         }
4324                         return ( $old->getRawUserText() === $new->getRawUserText() ) ? 1 : 2;
4325                 }
4326                 $dbr = wfGetDB( DB_SLAVE );
4327                 $res = $dbr->select( 'revision', 'DISTINCT rev_user_text',
4328                         array(
4329                                 'rev_page' => $this->getArticleID(),
4330                                 "rev_timestamp $old_cmp " . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4331                                 "rev_timestamp $new_cmp " . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4332                         ), __METHOD__,
4333                         array( 'LIMIT' => $limit + 1 ) // add one so caller knows it was truncated
4334                 );
4335                 return (int)$dbr->numRows( $res );
4336         }
4337
4338         /**
4339          * Compare with another title.
4340          *
4341          * @param $title Title
4342          * @return Bool
4343          */
4344         public function equals( Title $title ) {
4345                 // Note: === is necessary for proper matching of number-like titles.
4346                 return $this->getInterwiki() === $title->getInterwiki()
4347                         && $this->getNamespace() == $title->getNamespace()
4348                         && $this->getDBkey() === $title->getDBkey();
4349         }
4350
4351         /**
4352          * Check if this title is a subpage of another title
4353          *
4354          * @param $title Title
4355          * @return Bool
4356          */
4357         public function isSubpageOf( Title $title ) {
4358                 return $this->getInterwiki() === $title->getInterwiki()
4359                         && $this->getNamespace() == $title->getNamespace()
4360                         && strpos( $this->getDBkey(), $title->getDBkey() . '/' ) === 0;
4361         }
4362
4363         /**
4364          * Check if page exists.  For historical reasons, this function simply
4365          * checks for the existence of the title in the page table, and will
4366          * thus return false for interwiki links, special pages and the like.
4367          * If you want to know if a title can be meaningfully viewed, you should
4368          * probably call the isKnown() method instead.
4369          *
4370          * @return Bool
4371          */
4372         public function exists() {
4373                 return $this->getArticleID() != 0;
4374         }
4375
4376         /**
4377          * Should links to this title be shown as potentially viewable (i.e. as
4378          * "bluelinks"), even if there's no record by this title in the page
4379          * table?
4380          *
4381          * This function is semi-deprecated for public use, as well as somewhat
4382          * misleadingly named.  You probably just want to call isKnown(), which
4383          * calls this function internally.
4384          *
4385          * (ISSUE: Most of these checks are cheap, but the file existence check
4386          * can potentially be quite expensive.  Including it here fixes a lot of
4387          * existing code, but we might want to add an optional parameter to skip
4388          * it and any other expensive checks.)
4389          *
4390          * @return Bool
4391          */
4392         public function isAlwaysKnown() {
4393                 $isKnown = null;
4394
4395                 /**
4396                  * Allows overriding default behaviour for determining if a page exists.
4397                  * If $isKnown is kept as null, regular checks happen. If it's
4398                  * a boolean, this value is returned by the isKnown method.
4399                  *
4400                  * @since 1.20
4401                  *
4402                  * @param Title $title
4403                  * @param boolean|null $isKnown
4404                  */
4405                 wfRunHooks( 'TitleIsAlwaysKnown', array( $this, &$isKnown ) );
4406
4407                 if ( !is_null( $isKnown ) ) {
4408                         return $isKnown;
4409                 }
4410
4411                 if ( $this->mInterwiki != '' ) {
4412                         return true;  // any interwiki link might be viewable, for all we know
4413                 }
4414
4415                 switch( $this->mNamespace ) {
4416                         case NS_MEDIA:
4417                         case NS_FILE:
4418                                 // file exists, possibly in a foreign repo
4419                                 return (bool)wfFindFile( $this );
4420                         case NS_SPECIAL:
4421                                 // valid special page
4422                                 return SpecialPageFactory::exists( $this->getDBkey() );
4423                         case NS_MAIN:
4424                                 // selflink, possibly with fragment
4425                                 return $this->mDbkeyform == '';
4426                         case NS_MEDIAWIKI:
4427                                 // known system message
4428                                 return $this->hasSourceText() !== false;
4429                         default:
4430                                 return false;
4431                 }
4432         }
4433
4434         /**
4435          * Does this title refer to a page that can (or might) be meaningfully
4436          * viewed?  In particular, this function may be used to determine if
4437          * links to the title should be rendered as "bluelinks" (as opposed to
4438          * "redlinks" to non-existent pages).
4439          * Adding something else to this function will cause inconsistency
4440          * since LinkHolderArray calls isAlwaysKnown() and does its own
4441          * page existence check.
4442          *
4443          * @return Bool
4444          */
4445         public function isKnown() {
4446                 return $this->isAlwaysKnown() || $this->exists();
4447         }
4448
4449         /**
4450          * Does this page have source text?
4451          *
4452          * @return Boolean
4453          */
4454         public function hasSourceText() {
4455                 if ( $this->exists() ) {
4456                         return true;
4457                 }
4458
4459                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
4460                         // If the page doesn't exist but is a known system message, default
4461                         // message content will be displayed, same for language subpages-
4462                         // Use always content language to avoid loading hundreds of languages
4463                         // to get the link color.
4464                         global $wgContLang;
4465                         list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4466                         $message = wfMessage( $name )->inLanguage( $wgContLang )->useDatabase( false );
4467                         return $message->exists();
4468                 }
4469
4470                 return false;
4471         }
4472
4473         /**
4474          * Get the default message text or false if the message doesn't exist
4475          *
4476          * @return String or false
4477          */
4478         public function getDefaultMessageText() {
4479                 global $wgContLang;
4480
4481                 if ( $this->getNamespace() != NS_MEDIAWIKI ) { // Just in case
4482                         return false;
4483                 }
4484
4485                 list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4486                 $message = wfMessage( $name )->inLanguage( $lang )->useDatabase( false );
4487
4488                 if ( $message->exists() ) {
4489                         return $message->plain();
4490                 } else {
4491                         return false;
4492                 }
4493         }
4494
4495         /**
4496          * Updates page_touched for this page; called from LinksUpdate.php
4497          *
4498          * @return Bool true if the update succeded
4499          */
4500         public function invalidateCache() {
4501                 global $wgMemc;
4502                 if ( wfReadOnly() ) {
4503                         return false;
4504                 }
4505                 $dbw = wfGetDB( DB_MASTER );
4506                 $success = $dbw->update(
4507                         'page',
4508                         array( 'page_touched' => $dbw->timestamp() ),
4509                         $this->pageCond(),
4510                         __METHOD__
4511                 );
4512                 HTMLFileCache::clearFileCache( $this );
4513
4514                 // Clear page info.
4515                 $revision = WikiPage::factory( $this )->getRevision();
4516                 if( $revision !== null ) {
4517                         $memcKey = wfMemcKey( 'infoaction', $this->getPrefixedText(), $revision->getId() );
4518                         $success = $success && $wgMemc->delete( $memcKey );
4519                 }
4520
4521                 return $success;
4522         }
4523
4524         /**
4525          * Update page_touched timestamps and send squid purge messages for
4526          * pages linking to this title. May be sent to the job queue depending
4527          * on the number of links. Typically called on create and delete.
4528          */
4529         public function touchLinks() {
4530                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
4531                 $u->doUpdate();
4532
4533                 if ( $this->getNamespace() == NS_CATEGORY ) {
4534                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
4535                         $u->doUpdate();
4536                 }
4537         }
4538
4539         /**
4540          * Get the last touched timestamp
4541          *
4542          * @param $db DatabaseBase: optional db
4543          * @return String last-touched timestamp
4544          */
4545         public function getTouched( $db = null ) {
4546                 $db = isset( $db ) ? $db : wfGetDB( DB_SLAVE );
4547                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
4548                 return $touched;
4549         }
4550
4551         /**
4552          * Get the timestamp when this page was updated since the user last saw it.
4553          *
4554          * @param $user User
4555          * @return String|Null
4556          */
4557         public function getNotificationTimestamp( $user = null ) {
4558                 global $wgUser, $wgShowUpdatedMarker;
4559                 // Assume current user if none given
4560                 if ( !$user ) {
4561                         $user = $wgUser;
4562                 }
4563                 // Check cache first
4564                 $uid = $user->getId();
4565                 // avoid isset here, as it'll return false for null entries
4566                 if ( array_key_exists( $uid, $this->mNotificationTimestamp ) ) {
4567                         return $this->mNotificationTimestamp[$uid];
4568                 }
4569                 if ( !$uid || !$wgShowUpdatedMarker ) {
4570                         return $this->mNotificationTimestamp[$uid] = false;
4571                 }
4572                 // Don't cache too much!
4573                 if ( count( $this->mNotificationTimestamp ) >= self::CACHE_MAX ) {
4574                         $this->mNotificationTimestamp = array();
4575                 }
4576                 $dbr = wfGetDB( DB_SLAVE );
4577                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
4578                         'wl_notificationtimestamp',
4579                         array(
4580                                 'wl_user' => $user->getId(),
4581                                 'wl_namespace' => $this->getNamespace(),
4582                                 'wl_title' => $this->getDBkey(),
4583                         ),
4584                         __METHOD__
4585                 );
4586                 return $this->mNotificationTimestamp[$uid];
4587         }
4588
4589         /**
4590          * Generate strings used for xml 'id' names in monobook tabs
4591          *
4592          * @param $prepend string defaults to 'nstab-'
4593          * @return String XML 'id' name
4594          */
4595         public function getNamespaceKey( $prepend = 'nstab-' ) {
4596                 global $wgContLang;
4597                 // Gets the subject namespace if this title
4598                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
4599                 // Checks if cononical namespace name exists for namespace
4600                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
4601                         // Uses canonical namespace name
4602                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
4603                 } else {
4604                         // Uses text of namespace
4605                         $namespaceKey = $this->getSubjectNsText();
4606                 }
4607                 // Makes namespace key lowercase
4608                 $namespaceKey = $wgContLang->lc( $namespaceKey );
4609                 // Uses main
4610                 if ( $namespaceKey == '' ) {
4611                         $namespaceKey = 'main';
4612                 }
4613                 // Changes file to image for backwards compatibility
4614                 if ( $namespaceKey == 'file' ) {
4615                         $namespaceKey = 'image';
4616                 }
4617                 return $prepend . $namespaceKey;
4618         }
4619
4620         /**
4621          * Get all extant redirects to this Title
4622          *
4623          * @param $ns Int|Null Single namespace to consider; NULL to consider all namespaces
4624          * @return Array of Title redirects to this title
4625          */
4626         public function getRedirectsHere( $ns = null ) {
4627                 $redirs = array();
4628
4629                 $dbr = wfGetDB( DB_SLAVE );
4630                 $where = array(
4631                         'rd_namespace' => $this->getNamespace(),
4632                         'rd_title' => $this->getDBkey(),
4633                         'rd_from = page_id'
4634                 );
4635                 if ( $this->isExternal() ) {
4636                         $where['rd_interwiki'] = $this->getInterwiki();
4637                 } else {
4638                         $where[] = 'rd_interwiki = ' . $dbr->addQuotes( '' ) . ' OR rd_interwiki IS NULL';
4639                 }
4640                 if ( !is_null( $ns ) ) {
4641                         $where['page_namespace'] = $ns;
4642                 }
4643
4644                 $res = $dbr->select(
4645                         array( 'redirect', 'page' ),
4646                         array( 'page_namespace', 'page_title' ),
4647                         $where,
4648                         __METHOD__
4649                 );
4650
4651                 foreach ( $res as $row ) {
4652                         $redirs[] = self::newFromRow( $row );
4653                 }
4654                 return $redirs;
4655         }
4656
4657         /**
4658          * Check if this Title is a valid redirect target
4659          *
4660          * @return Bool
4661          */
4662         public function isValidRedirectTarget() {
4663                 global $wgInvalidRedirectTargets;
4664
4665                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
4666                 if ( $this->isSpecial( 'Userlogout' ) ) {
4667                         return false;
4668                 }
4669
4670                 foreach ( $wgInvalidRedirectTargets as $target ) {
4671                         if ( $this->isSpecial( $target ) ) {
4672                                 return false;
4673                         }
4674                 }
4675
4676                 return true;
4677         }
4678
4679         /**
4680          * Get a backlink cache object
4681          *
4682          * @return BacklinkCache
4683          */
4684         public function getBacklinkCache() {
4685                 return BacklinkCache::get( $this );
4686         }
4687
4688         /**
4689          * Whether the magic words __INDEX__ and __NOINDEX__ function for  this page.
4690          *
4691          * @return Boolean
4692          */
4693         public function canUseNoindex() {
4694                 global $wgContentNamespaces, $wgExemptFromUserRobotsControl;
4695
4696                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
4697                         ? $wgContentNamespaces
4698                         : $wgExemptFromUserRobotsControl;
4699
4700                 return !in_array( $this->mNamespace, $bannedNamespaces );
4701
4702         }
4703
4704         /**
4705          * Returns the raw sort key to be used for categories, with the specified
4706          * prefix.  This will be fed to Collation::getSortKey() to get a
4707          * binary sortkey that can be used for actual sorting.
4708          *
4709          * @param $prefix string The prefix to be used, specified using
4710          *   {{defaultsort:}} or like [[Category:Foo|prefix]].  Empty for no
4711          *   prefix.
4712          * @return string
4713          */
4714         public function getCategorySortkey( $prefix = '' ) {
4715                 $unprefixed = $this->getText();
4716
4717                 // Anything that uses this hook should only depend
4718                 // on the Title object passed in, and should probably
4719                 // tell the users to run updateCollations.php --force
4720                 // in order to re-sort existing category relations.
4721                 wfRunHooks( 'GetDefaultSortkey', array( $this, &$unprefixed ) );
4722                 if ( $prefix !== '' ) {
4723                         # Separate with a line feed, so the unprefixed part is only used as
4724                         # a tiebreaker when two pages have the exact same prefix.
4725                         # In UCA, tab is the only character that can sort above LF
4726                         # so we strip both of them from the original prefix.
4727                         $prefix = strtr( $prefix, "\n\t", '  ' );
4728                         return "$prefix\n$unprefixed";
4729                 }
4730                 return $unprefixed;
4731         }
4732
4733         /**
4734          * Get the language in which the content of this page is written in
4735          * wikitext. Defaults to $wgContLang, but in certain cases it can be
4736          * e.g. $wgLang (such as special pages, which are in the user language).
4737          *
4738          * @since 1.18
4739          * @return Language
4740          */
4741         public function getPageLanguage() {
4742                 global $wgLang;
4743                 if ( $this->isSpecialPage() ) {
4744                         // special pages are in the user language
4745                         return $wgLang;
4746                 }
4747
4748                 //TODO: use the LinkCache to cache this! Note that this may depend on user settings, so the cache should be only per-request.
4749                 //NOTE: ContentHandler::getPageLanguage() may need to load the content to determine the page language!
4750                 $contentHandler = ContentHandler::getForTitle( $this );
4751                 $pageLang = $contentHandler->getPageLanguage( $this );
4752
4753                 return wfGetLangObj( $pageLang );
4754         }
4755
4756         /**
4757          * Get the language in which the content of this page is written when
4758          * viewed by user. Defaults to $wgContLang, but in certain cases it can be
4759          * e.g. $wgLang (such as special pages, which are in the user language).
4760          *
4761          * @since 1.20
4762          * @return Language
4763          */
4764         public function getPageViewLanguage() {
4765                 global $wgLang;
4766
4767                 if ( $this->isSpecialPage() ) {
4768                         // If the user chooses a variant, the content is actually
4769                         // in a language whose code is the variant code.
4770                         $variant = $wgLang->getPreferredVariant();
4771                         if ( $wgLang->getCode() !== $variant ) {
4772                                 return Language::factory( $variant );
4773                         }
4774
4775                         return $wgLang;
4776                 }
4777
4778                 //NOTE: can't be cached persistently, depends on user settings
4779                 //NOTE: ContentHandler::getPageViewLanguage() may need to load the content to determine the page language!
4780                 $contentHandler = ContentHandler::getForTitle( $this );
4781                 $pageLang = $contentHandler->getPageViewLanguage( $this );
4782                 return $pageLang;
4783         }
4784
4785         /**
4786          * Get a list of rendered edit notices for this page.
4787          *
4788          * Array is keyed by the original message key, and values are rendered using parseAsBlock, so
4789          * they will already be wrapped in paragraphs.
4790          *
4791          * @since 1.21
4792          * @return Array
4793          */
4794         public function getEditNotices() {
4795                 $notices = array();
4796
4797                 # Optional notices on a per-namespace and per-page basis
4798                 $editnotice_ns = 'editnotice-' . $this->getNamespace();
4799                 $editnotice_ns_message = wfMessage( $editnotice_ns );
4800                 if ( $editnotice_ns_message->exists() ) {
4801                         $notices[$editnotice_ns] = $editnotice_ns_message->parseAsBlock();
4802                 }
4803                 if ( MWNamespace::hasSubpages( $this->getNamespace() ) ) {
4804                         $parts = explode( '/', $this->getDBkey() );
4805                         $editnotice_base = $editnotice_ns;
4806                         while ( count( $parts ) > 0 ) {
4807                                 $editnotice_base .= '-' . array_shift( $parts );
4808                                 $editnotice_base_msg = wfMessage( $editnotice_base );
4809                                 if ( $editnotice_base_msg->exists() ) {
4810                                         $notices[$editnotice_base] = $editnotice_base_msg->parseAsBlock();
4811                                 }
4812                         }
4813                 } else {
4814                         # Even if there are no subpages in namespace, we still don't want / in MW ns.
4815                         $editnoticeText = $editnotice_ns . '-' . str_replace( '/', '-', $this->getDBkey() );
4816                         $editnoticeMsg = wfMessage( $editnoticeText );
4817                         if ( $editnoticeMsg->exists() ) {
4818                                 $notices[$editnoticeText] = $editnoticeMsg->parseAsBlock();
4819                         }
4820                 }
4821                 return $notices;
4822         }
4823 }