includes/Title.php

   1 <?php
   2 /**
   3  * See title.txt
   4  * @file
   5  */
   6
   7 /**
   8  * @todo:  determine if it is really necessary to load this.  Appears to be left over from pre-autoloader versions, and
   9  *   is only really needed to provide access to constant UTF8_REPLACEMENT, which actually resides in UtfNormalDefines.php
  10  *   and is loaded by UtfNormalUtil.php, which is loaded by UtfNormal.php.
  11  */
  12 if ( !class_exists( 'UtfNormal' ) ) {
  13         require_once( dirname(__FILE__) . '/normal/UtfNormal.php' );
  14 }
  15
  16 define ( 'GAID_FOR_UPDATE', 1 );
  17
  18 /**
  19  * Represents a title within MediaWiki.
  20  * Optionally may contain an interwiki designation or namespace.
  21  * @note This class can fetch various kinds of data from the database;
  22  *       however, it does so inefficiently.
  23  *
  24  * @internal documentation reviewed 15 Mar 2010
  25  */
  26 class Title {
  27         /** @name Static cache variables */
  28         //@{
  29         static private $titleCache=array();
  30         static private $interwikiCache=array();
  31         //@}
  32
  33         /**
  34          * Title::newFromText maintains a cache to avoid expensive re-normalization of
  35          * commonly used titles. On a batch operation this can become a memory leak
  36          * if not bounded. After hitting this many titles reset the cache.
  37          */
  38         const CACHE_MAX = 1000;
  39
  40
  41         /**
  42          * @name Private member variables
  43          * Please use the accessor functions instead.
  44          * @private
  45          */
  46         //@{
  47
  48         var $mTextform = '';              ///< Text form (spaces not underscores) of the main part
  49         var $mUrlform = '';               ///< URL-encoded form of the main part
  50         var $mDbkeyform = '';             ///< Main part with underscores
  51         var $mUserCaseDBKey;              ///< DB key with the initial letter in the case specified by the user
  52         var $mNamespace = NS_MAIN;        ///< Namespace index, i.e. one of the NS_xxxx constants
  53         var $mInterwiki = '';             ///< Interwiki prefix (or null string)
  54         var $mFragment;                   ///< Title fragment (i.e. the bit after the #)
  55         var $mArticleID = -1;             ///< Article ID, fetched from the link cache on demand
  56         var $mLatestID = false;           ///< ID of most recent revision
  57         var $mRestrictions = array();     ///< Array of groups allowed to edit this article
  58         var $mOldRestrictions = false;
  59         var $mCascadeRestriction;         ///< Cascade restrictions on this page to included templates and images?
  60         var $mRestrictionsExpiry = array(); ///< When do the restrictions on this page expire?
  61         var $mHasCascadingRestrictions;   ///< Are cascading restrictions in effect on this page?
  62         var $mCascadeSources;             ///< Where are the cascading restrictions coming from on this page?
  63         var $mRestrictionsLoaded = false; ///< Boolean for initialisation on demand
  64         var $mPrefixedText;               ///< Text form including namespace/interwiki, initialised on demand
  65         # Don't change the following default, NS_MAIN is hardcoded in several
  66         # places.  See bug 696.
  67         var $mDefaultNamespace = NS_MAIN; ///< Namespace index when there is no namespace
  68                                           # Zero except in {{transclusion}} tags
  69         var $mWatched = null;             ///< Is $wgUser watching this page? null if unfilled, accessed through userIsWatching()
  70         var $mLength = -1;                ///< The page length, 0 for special pages
  71         var $mRedirect = null;            ///< Is the article at this title a redirect?
  72         var $mNotificationTimestamp = array(); ///< Associative array of user ID -> timestamp/false
  73         var $mBacklinkCache = null;       ///< Cache of links to this title
  74         //@}
  75
  76
  77         /**
  78          * Constructor
  79          * @private
  80          */
  81         /* private */ function __construct() {}
  82
  83         /**
  84          * Create a new Title from a prefixed DB key
  85          *
  86          * @param $key \type{\string} The database key, which has underscores
  87          *      instead of spaces, possibly including namespace and
  88          *      interwiki prefixes
  89          * @return \type{Title} the new object, or NULL on an error
  90          */
  91         public static function newFromDBkey( $key ) {
  92                 $t = new Title();
  93                 $t->mDbkeyform = $key;
  94                 if( $t->secureAndSplit() )
  95                         return $t;
  96                 else
  97                         return null;
  98         }
  99
 100         /**
 101          * Create a new Title from text, such as what one would find in a link. De-
 102          * codes any HTML entities in the text.
 103          *
 104          * @param $text string  The link text; spaces, prefixes, and an
 105          *   initial ':' indicating the main namespace are accepted.
 106          * @param $defaultNamespace int The namespace to use if none is speci-
 107          *   fied by a prefix.  If you want to force a specific namespace even if
 108          *   $text might begin with a namespace prefix, use makeTitle() or
 109          *   makeTitleSafe().
 110          * @return Title  The new object, or null on an error.
 111          */
 112         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 113                 if( is_object( $text ) ) {
 114                         throw new MWException( 'Title::newFromText given an object' );
 115                 }
 116
 117                 /**
 118                  * Wiki pages often contain multiple links to the same page.
 119                  * Title normalization and parsing can become expensive on
 120                  * pages with many links, so we can save a little time by
 121                  * caching them.
 122                  *
 123                  * In theory these are value objects and won't get changed...
 124                  */
 125                 if( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 126                         return Title::$titleCache[$text];
 127                 }
 128
 129                 /**
 130                  * Convert things like &eacute; &#257; or &#x3017; into normalized(bug 14952) text
 131                  */
 132                 $filteredText = Sanitizer::decodeCharReferencesAndNormalize( $text );
 133
 134                 $t = new Title();
 135                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 136                 $t->mDefaultNamespace = $defaultNamespace;
 137
 138                 static $cachedcount = 0 ;
 139                 if( $t->secureAndSplit() ) {
 140                         if( $defaultNamespace == NS_MAIN ) {
 141                                 if( $cachedcount >= self::CACHE_MAX ) {
 142                                         # Avoid memory leaks on mass operations...
 143                                         Title::$titleCache = array();
 144                                         $cachedcount=0;
 145                                 }
 146                                 $cachedcount++;
 147                                 Title::$titleCache[$text] =& $t;
 148                         }
 149                         return $t;
 150                 } else {
 151                         $ret = null;
 152                         return $ret;
 153                 }
 154         }
 155
 156         /**
 157          * THIS IS NOT THE FUNCTION YOU WANT. Use Title::newFromText().
 158          *
 159          * Example of wrong and broken code:
 160          * $title = Title::newFromURL( $wgRequest->getVal( 'title' ) );
 161          *
 162          * Example of right code:
 163          * $title = Title::newFromText( $wgRequest->getVal( 'title' ) );
 164          *
 165          * Create a new Title from URL-encoded text. Ensures that
 166          * the given title's length does not exceed the maximum.
 167          *
 168          * @param $url \type{\string} the title, as might be taken from a URL
 169          * @return \type{Title} the new object, or NULL on an error
 170          */
 171         public static function newFromURL( $url ) {
 172                 global $wgLegalTitleChars;
 173                 $t = new Title();
 174
 175                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 176                 # but some URLs used it as a space replacement and they still come
 177                 # from some external search tools.
 178                 if ( strpos( $wgLegalTitleChars, '+' ) === false ) {
 179                         $url = str_replace( '+', ' ', $url );
 180                 }
 181
 182                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 183                 if( $t->secureAndSplit() ) {
 184                         return $t;
 185                 } else {
 186                         return null;
 187                 }
 188         }
 189
 190         /**
 191          * Create a new Title from an article ID
 192          *
 193          * @param $id \type{\int} the page_id corresponding to the Title to create
 194          * @param $flags \type{\int} use GAID_FOR_UPDATE to use master
 195          * @return \type{Title} the new object, or NULL on an error
 196          */
 197         public static function newFromID( $id, $flags = 0 ) {
 198                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
 199                 $row = $db->selectRow( 'page', '*', array( 'page_id' => $id ), __METHOD__ );
 200                 if( $row !== false ) {
 201                         $title = Title::newFromRow( $row );
 202                 } else {
 203                         $title = null;
 204                 }
 205                 return $title;
 206         }
 207
 208         /**
 209          * Make an array of titles from an array of IDs
 210          *
 211          * @param $ids \type{\arrayof{\int}} Array of IDs
 212          * @return \type{\arrayof{Title}} Array of Titles
 213          */
 214         public static function newFromIDs( $ids ) {
 215                 if ( !count( $ids ) ) {
 216                         return array();
 217                 }
 218                 $dbr = wfGetDB( DB_SLAVE );
 219                 $res = $dbr->select( 'page', array( 'page_namespace', 'page_title' ),
 220                         'page_id IN (' . $dbr->makeList( $ids ) . ')', __METHOD__ );
 221
 222                 $titles = array();
 223                 foreach( $res as $row ) {
 224                         $titles[] = Title::makeTitle( $row->page_namespace, $row->page_title );
 225                 }
 226                 return $titles;
 227         }
 228
 229         /**
 230          * Make a Title object from a DB row
 231          *
 232          * @param $row \type{Row} (needs at least page_title,page_namespace)
 233          * @return \type{Title} corresponding Title
 234          */
 235         public static function newFromRow( $row ) {
 236                 $t = self::makeTitle( $row->page_namespace, $row->page_title );
 237
 238                 $t->mArticleID = isset($row->page_id) ? intval($row->page_id) : -1;
 239                 $t->mLength = isset($row->page_len) ? intval($row->page_len) : -1;
 240                 $t->mRedirect = isset($row->page_is_redirect) ? (bool)$row->page_is_redirect : null;
 241                 $t->mLatestID = isset($row->page_latest) ? $row->page_latest : false;
 242
 243                 return $t;
 244         }
 245
 246         /**
 247          * Create a new Title from a namespace index and a DB key.
 248          * It's assumed that $ns and $title are *valid*, for instance when
 249          * they came directly from the database or a special page name.
 250          * For convenience, spaces are converted to underscores so that
 251          * eg user_text fields can be used directly.
 252          *
 253          * @param $ns \type{\int} the namespace of the article
 254          * @param $title \type{\string} the unprefixed database key form
 255          * @param $fragment \type{\string} The link fragment (after the "#")
 256          * @return \type{Title} the new object
 257          */
 258         public static function &makeTitle( $ns, $title, $fragment = '' ) {
 259                 $t = new Title();
 260                 $t->mInterwiki = '';
 261                 $t->mFragment = $fragment;
 262                 $t->mNamespace = $ns = intval( $ns );
 263                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 264                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 265                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 266                 $t->mTextform = str_replace( '_', ' ', $title );
 267                 return $t;
 268         }
 269
 270         /**
 271          * Create a new Title from a namespace index and a DB key.
 272          * The parameters will be checked for validity, which is a bit slower
 273          * than makeTitle() but safer for user-provided data.
 274          *
 275          * @param $ns \type{\int} the namespace of the article
 276          * @param $title \type{\string} the database key form
 277          * @param $fragment \type{\string} The link fragment (after the "#")
 278          * @return \type{Title} the new object, or NULL on an error
 279          */
 280         public static function makeTitleSafe( $ns, $title, $fragment = '' ) {
 281                 $t = new Title();
 282                 $t->mDbkeyform = Title::makeName( $ns, $title, $fragment );
 283                 if( $t->secureAndSplit() ) {
 284                         return $t;
 285                 } else {
 286                         return null;
 287                 }
 288         }
 289
 290         /**
 291          * Create a new Title for the Main Page
 292          *
 293          * @return \type{Title} the new object
 294          */
 295         public static function newMainPage() {
 296                 $title = Title::newFromText( wfMsgForContent( 'mainpage' ) );
 297                 // Don't give fatal errors if the message is broken
 298                 if ( !$title ) {
 299                         $title = Title::newFromText( 'Main Page' );
 300                 }
 301                 return $title;
 302         }
 303
 304         /**
 305          * Extract a redirect destination from a string and return the
 306          * Title, or null if the text doesn't contain a valid redirect
 307          * This will only return the very next target, useful for
 308          * the redirect table and other checks that don't need full recursion
 309          *
 310          * @param $text \type{\string} Text with possible redirect
 311          * @return \type{Title} The corresponding Title
 312          */
 313         public static function newFromRedirect( $text ) {
 314                 return self::newFromRedirectInternal( $text );
 315         }
 316
 317         /**
 318          * Extract a redirect destination from a string and return the
 319          * Title, or null if the text doesn't contain a valid redirect
 320          * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
 321          * in order to provide (hopefully) the Title of the final destination instead of another redirect
 322          *
 323          * @param $text \type{\string} Text with possible redirect
 324          * @return \type{Title} The corresponding Title
 325          */
 326         public static function newFromRedirectRecurse( $text ) {
 327                 $titles = self::newFromRedirectArray( $text );
 328                 return $titles ? array_pop( $titles ) : null;
 329         }
 330
 331         /**
 332          * Extract a redirect destination from a string and return an
 333          * array of Titles, or null if the text doesn't contain a valid redirect
 334          * The last element in the array is the final destination after all redirects
 335          * have been resolved (up to $wgMaxRedirects times)
 336          *
 337          * @param $text \type{\string} Text with possible redirect
 338          * @return \type{\array} Array of Titles, with the destination last
 339          */
 340         public static function newFromRedirectArray( $text ) {
 341                 global $wgMaxRedirects;
 342                 // are redirects disabled?
 343                 if( $wgMaxRedirects < 1 )
 344                         return null;
 345                 $title = self::newFromRedirectInternal( $text );
 346                 if( is_null( $title ) )
 347                         return null;
 348                 // recursive check to follow double redirects
 349                 $recurse = $wgMaxRedirects;
 350                 $titles = array( $title );
 351                 while( --$recurse > 0 ) {
 352                         if( $title->isRedirect() ) {
 353                                 $article = new Article( $title, 0 );
 354                                 $newtitle = $article->getRedirectTarget();
 355                         } else {
 356                                 break;
 357                         }
 358                         // Redirects to some special pages are not permitted
 359                         if( $newtitle instanceOf Title && $newtitle->isValidRedirectTarget() ) {
 360                                 // the new title passes the checks, so make that our current title so that further recursion can be checked
 361                                 $title = $newtitle;
 362                                 $titles[] = $newtitle;
 363                         } else {
 364                                 break;
 365                         }
 366                 }
 367                 return $titles;
 368         }
 369
 370         /**
 371          * Really extract the redirect destination
 372          * Do not call this function directly, use one of the newFromRedirect* functions above
 373          *
 374          * @param $text \type{\string} Text with possible redirect
 375          * @return \type{Title} The corresponding Title
 376          */
 377         protected static function newFromRedirectInternal( $text ) {
 378                 $redir = MagicWord::get( 'redirect' );
 379                 $text = trim($text);
 380                 if( $redir->matchStartAndRemove( $text ) ) {
 381                         // Extract the first link and see if it's usable
 382                         // Ensure that it really does come directly after #REDIRECT
 383                         // Some older redirects included a colon, so don't freak about that!
 384                         $m = array();
 385                         if( preg_match( '!^\s*:?\s*\[{2}(.*?)(?:\|.*?)?\]{2}!', $text, $m ) ) {
 386                                 // Strip preceding colon used to "escape" categories, etc.
 387                                 // and URL-decode links
 388                                 if( strpos( $m[1], '%' ) !== false ) {
 389                                         // Match behavior of inline link parsing here;
 390                                         // don't interpret + as " " most of the time!
 391                                         // It might be safe to just use rawurldecode instead, though.
 392                                         $m[1] = urldecode( ltrim( $m[1], ':' ) );
 393                                 }
 394                                 $title = Title::newFromText( $m[1] );
 395                                 // If the title is a redirect to bad special pages or is invalid, return null
 396                                 if( !$title instanceof Title || !$title->isValidRedirectTarget() ) {
 397                                         return null;
 398                                 }
 399                                 return $title;
 400                         }
 401                 }
 402                 return null;
 403         }
 404
 405 #----------------------------------------------------------------------------
 406 #       Static functions
 407 #----------------------------------------------------------------------------
 408
 409         /**
 410          * Get the prefixed DB key associated with an ID
 411          *
 412          * @param $id \type{\int} the page_id of the article
 413          * @return \type{Title} an object representing the article, or NULL
 414          *  if no such article was found
 415          */
 416         public static function nameOf( $id ) {
 417                 $dbr = wfGetDB( DB_SLAVE );
 418
 419                 $s = $dbr->selectRow( 'page',
 420                         array( 'page_namespace','page_title' ),
 421                         array( 'page_id' => $id ),
 422                         __METHOD__ );
 423                 if ( $s === false ) { return null; }
 424
 425                 $n = self::makeName( $s->page_namespace, $s->page_title );
 426                 return $n;
 427         }
 428
 429         /**
 430          * Get a regex character class describing the legal characters in a link
 431          *
 432          * @return \type{\string} the list of characters, not delimited
 433          */
 434         public static function legalChars() {
 435                 global $wgLegalTitleChars;
 436                 return $wgLegalTitleChars;
 437         }
 438
 439         /**
 440          * Get a string representation of a title suitable for
 441          * including in a search index
 442          *
 443          * @param $ns \type{\int} a namespace index
 444          * @param $title \type{\string} text-form main part
 445          * @return \type{\string} a stripped-down title string ready for the
 446          *  search index
 447          */
 448         public static function indexTitle( $ns, $title ) {
 449                 global $wgContLang;
 450
 451                 $lc = SearchEngine::legalSearchChars() . '&#;';
 452                 $t = $wgContLang->normalizeForSearch( $title );
 453                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 454                 $t = $wgContLang->lc( $t );
 455
 456                 # Handle 's, s'
 457                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 458                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 459
 460                 $t = preg_replace( "/\\s+/", ' ', $t );
 461
 462                 if ( $ns == NS_FILE ) {
 463                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 464                 }
 465                 return trim( $t );
 466         }
 467
 468         /**
 469          * Make a prefixed DB key from a DB key and a namespace index
 470          *
 471          * @param $ns \type{\int} numerical representation of the namespace
 472          * @param $title \type{\string} the DB key form the title
 473          * @param $fragment \type{\string} The link fragment (after the "#")
 474          * @return \type{\string} the prefixed form of the title
 475          */
 476         public static function makeName( $ns, $title, $fragment = '' ) {
 477                 global $wgContLang;
 478
 479                 $namespace = $wgContLang->getNsText( $ns );
 480                 $name = $namespace == '' ? $title : "$namespace:$title";
 481                 if ( strval( $fragment ) != '' ) {
 482                         $name .= '#' . $fragment;
 483                 }
 484                 return $name;
 485         }
 486
 487         /**
 488          * Determine whether the object refers to a page within
 489          * this project.
 490          *
 491          * @return \type{\bool} TRUE if this is an in-project interwiki link
 492          *      or a wikilink, FALSE otherwise
 493          */
 494         public function isLocal() {
 495                 if ( $this->mInterwiki != '' ) {
 496                         return Interwiki::fetch( $this->mInterwiki )->isLocal();
 497                 } else {
 498                         return true;
 499                 }
 500         }
 501
 502         /**
 503          * Determine whether the object refers to a page within
 504          * this project and is transcludable.
 505          *
 506          * @return \type{\bool} TRUE if this is transcludable
 507          */
 508         public function isTrans() {
 509                 if ($this->mInterwiki == '')
 510                         return false;
 511
 512                 return Interwiki::fetch( $this->mInterwiki )->isTranscludable();
 513         }
 514
 515         /**
 516          * Escape a text fragment, say from a link, for a URL
 517          *
 518          * @param $fragment string containing a URL or link fragment (after the "#")
 519          * @return String: escaped string
 520          */
 521         static function escapeFragmentForURL( $fragment ) {
 522                 # Note that we don't urlencode the fragment.  urlencoded Unicode
 523                 # fragments appear not to work in IE (at least up to 7) or in at least
 524                 # one version of Opera 9.x.  The W3C validator, for one, doesn't seem
 525                 # to care if they aren't encoded.
 526                 return Sanitizer::escapeId( $fragment, 'noninitial' );
 527         }
 528
 529 #----------------------------------------------------------------------------
 530 #       Other stuff
 531 #----------------------------------------------------------------------------
 532
 533         /** Simple accessors */
 534         /**
 535          * Get the text form (spaces not underscores) of the main part
 536          *
 537          * @return \type{\string} Main part of the title
 538          */
 539         public function getText() { return $this->mTextform; }
 540
 541         /**
 542          * Get the URL-encoded form of the main part
 543          *
 544          * @return \type{\string} Main part of the title, URL-encoded
 545          */
 546         public function getPartialURL() { return $this->mUrlform; }
 547
 548         /**
 549          * Get the main part with underscores
 550          *
 551          * @return \type{\string} Main part of the title, with underscores
 552          */
 553         public function getDBkey() { return $this->mDbkeyform; }
 554
 555         /**
 556          * Get the namespace index, i.e.\ one of the NS_xxxx constants.
 557          *
 558          * @return \type{\int} Namespace index
 559          */
 560         public function getNamespace() { return $this->mNamespace; }
 561
 562         /**
 563          * Get the namespace text
 564          *
 565          * @return \type{\string} Namespace text
 566          */
 567         public function getNsText() {
 568                 global $wgContLang;
 569
 570                 if ( $this->mInterwiki != '' ) {
 571                         // This probably shouldn't even happen. ohh man, oh yuck.
 572                         // But for interwiki transclusion it sometimes does.
 573                         // Shit. Shit shit shit.
 574                         //
 575                         // Use the canonical namespaces if possible to try to
 576                         // resolve a foreign namespace.
 577                         if( MWNamespace::exists( $this->mNamespace ) ) {
 578                                 return MWNamespace::getCanonicalName( $this->mNamespace );
 579                         }
 580                 }
 581                 return $wgContLang->getNsText( $this->mNamespace );
 582         }
 583
 584         /**
 585          * Get the DB key with the initial letter case as specified by the user
 586          *
 587          * @return \type{\string} DB key
 588          */
 589         function getUserCaseDBKey() {
 590                 return $this->mUserCaseDBKey;
 591         }
 592
 593         /**
 594          * Get the namespace text of the subject (rather than talk) page
 595          *
 596          * @return \type{\string} Namespace text
 597          */
 598         public function getSubjectNsText() {
 599                 global $wgContLang;
 600                 return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
 601         }
 602
 603         /**
 604          * Get the namespace text of the talk page
 605          *
 606          * @return \type{\string} Namespace text
 607          */
 608         public function getTalkNsText() {
 609                 global $wgContLang;
 610                 return( $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) ) );
 611         }
 612
 613         /**
 614          * Could this title have a corresponding talk page?
 615          *
 616          * @return \type{\bool} TRUE or FALSE
 617          */
 618         public function canTalk() {
 619                 return( MWNamespace::canTalk( $this->mNamespace ) );
 620         }
 621
 622         /**
 623          * Get the interwiki prefix (or null string)
 624          *
 625          * @return \type{\string} Interwiki prefix
 626          */
 627         public function getInterwiki() { return $this->mInterwiki; }
 628
 629         /**
 630          * Get the Title fragment (i.e.\ the bit after the #) in text form
 631          *
 632          * @return \type{\string} Title fragment
 633          */
 634         public function getFragment() { return $this->mFragment; }
 635
 636         /**
 637          * Get the fragment in URL form, including the "#" character if there is one
 638          * @return \type{\string} Fragment in URL form
 639          */
 640         public function getFragmentForURL() {
 641                 if ( $this->mFragment == '' ) {
 642                         return '';
 643                 } else {
 644                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
 645                 }
 646         }
 647
 648         /**
 649          * Get the default namespace index, for when there is no namespace
 650          *
 651          * @return \type{\int} Default namespace index
 652          */
 653         public function getDefaultNamespace() { return $this->mDefaultNamespace; }
 654
 655         /**
 656          * Get title for search index
 657          *
 658          * @return \type{\string} a stripped-down title string ready for the
 659          *  search index
 660          */
 661         public function getIndexTitle() {
 662                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 663         }
 664
 665         /**
 666          * Get the prefixed database key form
 667          *
 668          * @return \type{\string} the prefixed title, with underscores and
 669          *  any interwiki and namespace prefixes
 670          */
 671         public function getPrefixedDBkey() {
 672                 $s = $this->prefix( $this->mDbkeyform );
 673                 $s = str_replace( ' ', '_', $s );
 674                 return $s;
 675         }
 676
 677         /**
 678          * Get the prefixed title with spaces.
 679          * This is the form usually used for display
 680          *
 681          * @return \type{\string} the prefixed title, with spaces
 682          */
 683         public function getPrefixedText() {
 684                 if ( empty( $this->mPrefixedText ) ) { // FIXME: bad usage of empty() ?
 685                         $s = $this->prefix( $this->mTextform );
 686                         $s = str_replace( '_', ' ', $s );
 687                         $this->mPrefixedText = $s;
 688                 }
 689                 return $this->mPrefixedText;
 690         }
 691
 692         /**
 693          * Get the prefixed title with spaces, plus any fragment
 694          * (part beginning with '#')
 695          *
 696          * @return \type{\string} the prefixed title, with spaces and
 697          *  the fragment, including '#'
 698          */
 699         public function getFullText() {
 700                 $text = $this->getPrefixedText();
 701                 if( $this->mFragment != '' ) {
 702                         $text .= '#' . $this->mFragment;
 703                 }
 704                 return $text;
 705         }
 706
 707         /**
 708          * Get the base name, i.e. the leftmost parts before the /
 709          *
 710          * @return \type{\string} Base name
 711          */
 712         public function getBaseText() {
 713                 if( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
 714                         return $this->getText();
 715                 }
 716
 717                 $parts = explode( '/', $this->getText() );
 718                 # Don't discard the real title if there's no subpage involved
 719                 if( count( $parts ) > 1 )
 720                         unset( $parts[ count( $parts ) - 1 ] );
 721                 return implode( '/', $parts );
 722         }
 723
 724         /**
 725          * Get the lowest-level subpage name, i.e. the rightmost part after /
 726          *
 727          * @return \type{\string} Subpage name
 728          */
 729         public function getSubpageText() {
 730                 if( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
 731                         return( $this->mTextform );
 732                 }
 733                 $parts = explode( '/', $this->mTextform );
 734                 return( $parts[ count( $parts ) - 1 ] );
 735         }
 736
 737         /**
 738          * Get a URL-encoded form of the subpage text
 739          *
 740          * @return \type{\string} URL-encoded subpage name
 741          */
 742         public function getSubpageUrlForm() {
 743                 $text = $this->getSubpageText();
 744                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
 745                 return( $text );
 746         }
 747
 748         /**
 749          * Get a URL-encoded title (not an actual URL) including interwiki
 750          *
 751          * @return \type{\string} the URL-encoded form
 752          */
 753         public function getPrefixedURL() {
 754                 $s = $this->prefix( $this->mDbkeyform );
 755                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
 756                 return $s;
 757         }
 758
 759         /**
 760          * Get a real URL referring to this title, with interwiki link and
 761          * fragment
 762          *
 763          * @param $query \twotypes{\string,\array} an optional query string, not used for interwiki
 764          *   links. Can be specified as an associative array as well, e.g.,
 765          *   array( 'action' => 'edit' ) (keys and values will be URL-escaped).
 766          * @param $variant \type{\string} language variant of url (for sr, zh..)
 767          * @return \type{\string} the URL
 768          */
 769         public function getFullURL( $query = '', $variant = false ) {
 770                 global $wgContLang, $wgServer, $wgRequest;
 771
 772                 if( is_array( $query ) ) {
 773                         $query = wfArrayToCGI( $query );
 774                 }
 775
 776                 $interwiki = Interwiki::fetch( $this->mInterwiki );
 777                 if ( !$interwiki ) {
 778                         $url = $this->getLocalURL( $query, $variant );
 779
 780                         // Ugly quick hack to avoid duplicate prefixes (bug 4571 etc)
 781                         // Correct fix would be to move the prepending elsewhere.
 782                         if ($wgRequest->getVal('action') != 'render') {
 783                                 $url = $wgServer . $url;
 784                         }
 785                 } else {
 786                         $baseUrl = $interwiki->getURL( );
 787
 788                         $namespace = wfUrlencode( $this->getNsText() );
 789                         if ( $namespace != '' ) {
 790                                 # Can this actually happen? Interwikis shouldn't be parsed.
 791                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
 792                                 $namespace .= ':';
 793                         }
 794                         $url = str_replace( '$1', $namespace . $this->mUrlform, $baseUrl );
 795                         $url = wfAppendQuery( $url, $query );
 796                 }
 797
 798                 # Finally, add the fragment.
 799                 $url .= $this->getFragmentForURL();
 800
 801                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
 802                 return $url;
 803         }
 804
 805         /**
 806          * Get a URL with no fragment or server name.  If this page is generated
 807          * with action=render, $wgServer is prepended.
 808          *
 809          * @param $query Mixed: an optional query string; if not specified,
 810          *   $wgArticlePath will be used.  Can be specified as an associative array
 811          *   as well, e.g., array( 'action' => 'edit' ) (keys and values will be
 812          *   URL-escaped).
 813          * @param $variant \type{\string} language variant of url (for sr, zh..)
 814          * @return \type{\string} the URL
 815          */
 816         public function getLocalURL( $query = '', $variant = false ) {
 817                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
 818                 global $wgVariantArticlePath, $wgContLang, $wgUser;
 819
 820                 if( is_array( $query ) ) {
 821                         $query = wfArrayToCGI( $query );
 822                 }
 823
 824                 // internal links should point to same variant as current page (only anonymous users)
 825                 if($variant == false && $wgContLang->hasVariants() && !$wgUser->isLoggedIn()){
 826                         $pref = $wgContLang->getPreferredVariant(false);
 827                         if($pref != $wgContLang->getCode())
 828                                 $variant = $pref;
 829                 } elseif ( $variant == $wgContLang->getCode() ) {
 830                         // Don't use $wgVariantArticlePath for the main code
 831                         $variant = false;
 832                 }
 833
 834                 if ( $this->isExternal() ) {
 835                         $url = $this->getFullURL();
 836                         if ( $query ) {
 837                                 // This is currently only used for edit section links in the
 838                                 // context of interwiki transclusion. In theory we should
 839                                 // append the query to the end of any existing query string,
 840                                 // but interwiki transclusion is already broken in that case.
 841                                 $url .= "?$query";
 842                         }
 843                 } else {
 844                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 845                         if ( $query == '' ) {
 846                                 if( $variant != false && $wgContLang->hasVariants() ) {
 847                                         if( $wgVariantArticlePath == false ) {
 848                                                 $variantArticlePath =  "$wgScript?title=$1&variant=$2"; // default
 849                                         } else {
 850                                                 $variantArticlePath = $wgVariantArticlePath;
 851                                         }
 852                                         $url = str_replace( '$2', urlencode( $variant ), $variantArticlePath );
 853                                         $url = str_replace( '$1', $dbkey, $url  );
 854                                 } else {
 855                                         $url = str_replace( '$1', $dbkey, $wgArticlePath );
 856                                 }
 857                         } else {
 858                                 global $wgActionPaths;
 859                                 $url = false;
 860                                 $matches = array();
 861                                 if( !empty( $wgActionPaths ) &&
 862                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
 863                                 {
 864                                         $action = urldecode( $matches[2] );
 865                                         if( isset( $wgActionPaths[$action] ) ) {
 866                                                 $query = $matches[1];
 867                                                 if( isset( $matches[4] ) ) $query .= $matches[4];
 868                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
 869                                                 if( $query != '' ) {
 870                                                         $url = wfAppendQuery( $url, $query );
 871                                                 }
 872                                         }
 873                                 }
 874                                 if ( $url === false ) {
 875                                         if ( $query == '-' ) {
 876                                                 $query = '';
 877                                         }
 878                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
 879                                 }
 880                         }
 881
 882                         // FIXME: this causes breakage in various places when we
 883                         // actually expected a local URL and end up with dupe prefixes.
 884                         if ($wgRequest->getVal('action') == 'render') {
 885                                 $url = $wgServer . $url;
 886                         }
 887                 }
 888                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
 889                 return $url;
 890         }
 891
 892         /**
 893          * Get a URL that's the simplest URL that will be valid to link, locally,
 894          * to the current Title.  It includes the fragment, but does not include
 895          * the server unless action=render is used (or the link is external).  If
 896          * there's a fragment but the prefixed text is empty, we just return a link
 897          * to the fragment.
 898          *
 899          * The result obviously should not be URL-escaped, but does need to be
 900          * HTML-escaped if it's being output in HTML.
 901          *
 902          * @param $query \type{\arrayof{\string}} An associative array of key => value pairs for the
 903          *   query string.  Keys and values will be escaped.
 904          * @param $variant \type{\string} Language variant of URL (for sr, zh..).  Ignored
 905          *   for external links.  Default is "false" (same variant as current page,
 906          *   for anonymous users).
 907          * @return \type{\string} the URL
 908          */
 909         public function getLinkUrl( $query = array(), $variant = false ) {
 910                 wfProfileIn( __METHOD__ );
 911                 if( $this->isExternal() ) {
 912                         $ret = $this->getFullURL( $query );
 913                 } elseif( $this->getPrefixedText() === '' && $this->getFragment() !== '' ) {
 914                         $ret = $this->getFragmentForURL();
 915                 } else {
 916                         $ret = $this->getLocalURL( $query, $variant ) . $this->getFragmentForURL();
 917                 }
 918                 wfProfileOut( __METHOD__ );
 919                 return $ret;
 920         }
 921
 922         /**
 923          * Get an HTML-escaped version of the URL form, suitable for
 924          * using in a link, without a server name or fragment
 925          *
 926          * @param $query \type{\string} an optional query string
 927          * @return \type{\string} the URL
 928          */
 929         public function escapeLocalURL( $query = '' ) {
 930                 return htmlspecialchars( $this->getLocalURL( $query ) );
 931         }
 932
 933         /**
 934          * Get an HTML-escaped version of the URL form, suitable for
 935          * using in a link, including the server name and fragment
 936          *
 937          * @param $query \type{\string} an optional query string
 938          * @return \type{\string} the URL
 939          */
 940         public function escapeFullURL( $query = '' ) {
 941                 return htmlspecialchars( $this->getFullURL( $query ) );
 942         }
 943
 944         /**
 945          * Get the URL form for an internal link.
 946          * - Used in various Squid-related code, in case we have a different
 947          * internal hostname for the server from the exposed one.
 948          *
 949          * @param $query \type{\string} an optional query string
 950          * @param $variant \type{\string} language variant of url (for sr, zh..)
 951          * @return \type{\string} the URL
 952          */
 953         public function getInternalURL( $query = '', $variant = false ) {
 954                 global $wgInternalServer;
 955                 $url = $wgInternalServer . $this->getLocalURL( $query, $variant );
 956                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
 957                 return $url;
 958         }
 959
 960         /**
 961          * Get the edit URL for this Title
 962          *
 963          * @return \type{\string} the URL, or a null string if this is an
 964          *  interwiki link
 965          */
 966         public function getEditURL() {
 967                 if ( $this->mInterwiki != '' ) { return ''; }
 968                 $s = $this->getLocalURL( 'action=edit' );
 969
 970                 return $s;
 971         }
 972
 973         /**
 974          * Get the HTML-escaped displayable text form.
 975          * Used for the title field in <a> tags.
 976          *
 977          * @return \type{\string} the text, including any prefixes
 978          */
 979         public function getEscapedText() {
 980                 return htmlspecialchars( $this->getPrefixedText() );
 981         }
 982
 983         /**
 984          * Is this Title interwiki?
 985          *
 986          * @return \type{\bool}
 987          */
 988         public function isExternal() { return ( $this->mInterwiki != '' ); }
 989
 990         /**
 991          * Is this page "semi-protected" - the *only* protection is autoconfirm?
 992          *
 993          * @param $action \type{\string} Action to check (default: edit)
 994          * @return \type{\bool}
 995          */
 996         public function isSemiProtected( $action = 'edit' ) {
 997                 if( $this->exists() ) {
 998                         $restrictions = $this->getRestrictions( $action );
 999                         if( count( $restrictions ) > 0 ) {
1000                                 foreach( $restrictions as $restriction ) {
1001                                         if( strtolower( $restriction ) != 'autoconfirmed' )
1002                                                 return false;
1003                                 }
1004                         } else {
1005                                 # Not protected
1006                                 return false;
1007                         }
1008                         return true;
1009                 } else {
1010                         # If it doesn't exist, it can't be protected
1011                         return false;
1012                 }
1013         }
1014
1015         /**
1016          * Does the title correspond to a protected article?
1017          *
1018          * @param $action \type{\string} the action the page is protected from,
1019          * by default checks all actions.
1020          * @return \type{\bool}
1021          */
1022         public function isProtected( $action = '' ) {
1023                 global $wgRestrictionLevels;
1024
1025                 $restrictionTypes = $this->getRestrictionTypes();
1026
1027                 # Special pages have inherent protection
1028                 if( $this->getNamespace() == NS_SPECIAL )
1029                         return true;
1030
1031                 # Check regular protection levels
1032                 foreach( $restrictionTypes as $type ){
1033                         if( $action == $type || $action == '' ) {
1034                                 $r = $this->getRestrictions( $type );
1035                                 foreach( $wgRestrictionLevels as $level ) {
1036                                         if( in_array( $level, $r ) && $level != '' ) {
1037                                                 return true;
1038                                         }
1039                                 }
1040                         }
1041                 }
1042
1043                 return false;
1044         }
1045
1046         /**
1047          * Is this a conversion table for the LanguageConverter?
1048          *
1049          * @return \type{\bool}
1050          */
1051         public function isConversionTable() {
1052                 if($this->getNamespace() == NS_MEDIAWIKI
1053                    && strpos( $this->getText(), 'Conversiontable' ) !== false ) {
1054                         return true;
1055                 }
1056
1057                 return false;
1058         }
1059
1060         /**
1061          * Is $wgUser watching this page?
1062          *
1063          * @return \type{\bool}
1064          */
1065         public function userIsWatching() {
1066                 global $wgUser;
1067
1068                 if ( is_null( $this->mWatched ) ) {
1069                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn()) {
1070                                 $this->mWatched = false;
1071                         } else {
1072                                 $this->mWatched = $wgUser->isWatched( $this );
1073                         }
1074                 }
1075                 return $this->mWatched;
1076         }
1077
1078         /**
1079          * Can $wgUser perform $action on this page?
1080          * This skips potentially expensive cascading permission checks
1081          * as well as avoids expensive error formatting
1082          *
1083          * Suitable for use for nonessential UI controls in common cases, but
1084          * _not_ for functional access control.
1085          *
1086          * May provide false positives, but should never provide a false negative.
1087          *
1088          * @param $action \type{\string} action that permission needs to be checked for
1089          * @return \type{\bool}
1090          */
1091         public function quickUserCan( $action ) {
1092                 return $this->userCan( $action, false );
1093         }
1094
1095         /**
1096          * Determines if $wgUser is unable to edit this page because it has been protected
1097          * by $wgNamespaceProtection.
1098          *
1099          * @return \type{\bool}
1100          */
1101         public function isNamespaceProtected() {
1102                 global $wgNamespaceProtection, $wgUser;
1103                 if( isset( $wgNamespaceProtection[ $this->mNamespace ] ) ) {
1104                         foreach( (array)$wgNamespaceProtection[ $this->mNamespace ] as $right ) {
1105                                 if( $right != '' && !$wgUser->isAllowed( $right ) )
1106                                         return true;
1107                         }
1108                 }
1109                 return false;
1110         }
1111
1112         /**
1113          * Can $wgUser perform $action on this page?
1114          *
1115          * @param $action \type{\string} action that permission needs to be checked for
1116          * @param $doExpensiveQueries \type{\bool} Set this to false to avoid doing unnecessary queries.
1117          * @return \type{\bool}
1118          */
1119         public function userCan( $action, $doExpensiveQueries = true ) {
1120                 global $wgUser;
1121                 return ($this->getUserPermissionsErrorsInternal( $action, $wgUser, $doExpensiveQueries, true ) === array());
1122         }
1123
1124         /**
1125          * Can $user perform $action on this page?
1126          *
1127          * FIXME: This *does not* check throttles (User::pingLimiter()).
1128          *
1129          * @param $action \type{\string}action that permission needs to be checked for
1130          * @param $user \type{User} user to check
1131          * @param $doExpensiveQueries \type{\bool} Set this to false to avoid doing unnecessary queries.
1132          * @param $ignoreErrors \type{\arrayof{\string}} Set this to a list of message keys whose corresponding errors may be ignored.
1133          * @return \type{\array} Array of arrays of the arguments to wfMsg to explain permissions problems.
1134          */
1135         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1136                 if( !StubObject::isRealObject( $user ) ) {
1137                         //Since StubObject is always used on globals, we can unstub $wgUser here and set $user = $wgUser
1138                         global $wgUser;
1139                         $wgUser->_unstub( '', 5 );
1140                         $user = $wgUser;
1141                 }
1142                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1143
1144                 global $wgContLang;
1145                 global $wgLang;
1146                 global $wgEmailConfirmToEdit;
1147
1148                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() && $action != 'createaccount' ) {
1149                         $errors[] = array( 'confirmedittext' );
1150                 }
1151
1152                 // Edit blocks should not affect reading. Account creation blocks handled at userlogin.
1153                 if ( $action != 'read' && $action != 'createaccount' && $user->isBlockedFrom( $this ) ) {
1154                         $block = $user->mBlock;
1155
1156                         // This is from OutputPage::blockedPage
1157                         // Copied at r23888 by werdna
1158
1159                         $id = $user->blockedBy();
1160                         $reason = $user->blockedFor();
1161                         if( $reason == '' ) {
1162                                 $reason = wfMsg( 'blockednoreason' );
1163                         }
1164                         $ip = wfGetIP();
1165
1166                         if ( is_numeric( $id ) ) {
1167                                 $name = User::whoIs( $id );
1168                         } else {
1169                                 $name = $id;
1170                         }
1171
1172                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1173                         $blockid = $block->mId;
1174                         $blockExpiry = $user->mBlock->mExpiry;
1175                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $user->mBlock->mTimestamp ), true );
1176
1177                         if ( $blockExpiry == 'infinity' ) {
1178                                 // Entry in database (table ipblocks) is 'infinity' but 'ipboptions' uses 'infinite' or 'indefinite'
1179                                 $scBlockExpiryOptions = wfMsg( 'ipboptions' );
1180
1181                                 foreach ( explode( ',', $scBlockExpiryOptions ) as $option ) {
1182                                         if ( strpos( $option, ':' ) == false )
1183                                                 continue;
1184
1185                                         list ($show, $value) = explode( ":", $option );
1186
1187                                         if ( $value == 'infinite' || $value == 'indefinite' ) {
1188                                                 $blockExpiry = $show;
1189                                                 break;
1190                                         }
1191                                 }
1192                         } else {
1193                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1194                         }
1195
1196                         $intended = $user->mBlock->mAddress;
1197
1198                         $errors[] = array( ($block->mAuto ? 'autoblockedtext' : 'blockedtext'), $link, $reason, $ip, $name,
1199                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
1200                 }
1201
1202                 // Remove the errors being ignored.
1203
1204                 foreach( $errors as $index => $error ) {
1205                         $error_key = is_array($error) ? $error[0] : $error;
1206
1207                         if (in_array( $error_key, $ignoreErrors )) {
1208                                 unset($errors[$index]);
1209                         }
1210                 }
1211
1212                 return $errors;
1213         }
1214
1215         /**
1216          * Can $user perform $action on this page? This is an internal function,
1217          * which checks ONLY that previously checked by userCan (i.e. it leaves out
1218          * checks on wfReadOnly() and blocks)
1219          *
1220          * @param $action \type{\string} action that permission needs to be checked for
1221          * @param $user \type{User} user to check
1222          * @param $doExpensiveQueries \type{\bool} Set this to false to avoid doing unnecessary queries.
1223          * @param $short \type{\bool} Set this to true to stop after the first permission error.
1224          * @return \type{\array} Array of arrays of the arguments to wfMsg to explain permissions problems.
1225          */
1226         private function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries=true, $short=false ) {
1227                 wfProfileIn( __METHOD__ );
1228
1229                 $errors = array();
1230
1231                 // First stop is permissions checks, which fail most often, and which are easiest to test.
1232                 if ( $action == 'move' ) {
1233                         if( !$user->isAllowed( 'move-rootuserpages' )
1234                                         && $this->getNamespace() == NS_USER && !$this->isSubpage() )
1235                         {
1236                                 // Show user page-specific message only if the user can move other pages
1237                                 $errors[] = array( 'cant-move-user-page' );
1238                         }
1239
1240                         // Check if user is allowed to move files if it's a file
1241                         if( $this->getNamespace() == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1242                                 $errors[] = array( 'movenotallowedfile' );
1243                         }
1244
1245                         if( !$user->isAllowed( 'move' ) ) {
1246                                 // User can't move anything
1247                                 global $wgGroupPermissions;
1248                                 $userCanMove = false;
1249                                 if ( isset( $wgGroupPermissions['user']['move'] ) ) {
1250                                         $userCanMove = $wgGroupPermissions['user']['move'];
1251                                 }
1252                                 $autoconfirmedCanMove = false;
1253                                 if ( isset( $wgGroupPermissions['autoconfirmed']['move'] ) ) {
1254                                         $autoconfirmedCanMove = $wgGroupPermissions['autoconfirmed']['move'];
1255                                 }
1256                                 if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
1257                                         // custom message if logged-in users without any special rights can move
1258                                         $errors[] = array ( 'movenologintext' );
1259                                 } else {
1260                                         $errors[] = array ('movenotallowed');
1261                                 }
1262                         }
1263                 } elseif ( $action == 'create' ) {
1264                         if( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1265                                 ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) )
1266                         {
1267                                 $errors[] = $user->isAnon() ? array ('nocreatetext') : array ('nocreate-loggedin');
1268                         }
1269                 } elseif( $action == 'move-target' ) {
1270                         if( !$user->isAllowed( 'move' ) ) {
1271                                 // User can't move anything
1272                                 $errors[] = array ('movenotallowed');
1273                         } elseif( !$user->isAllowed( 'move-rootuserpages' )
1274                                 && $this->getNamespace() == NS_USER && !$this->isSubpage() )
1275                         {
1276                                 // Show user page-specific message only if the user can move other pages
1277                                 $errors[] = array( 'cant-move-to-user-page' );
1278                         }
1279                 } elseif( !$user->isAllowed( $action ) ) {
1280                         $return = null;
1281
1282                         // We avoid expensive display logic for quickUserCan's and such
1283                         $groups = false;
1284                         if (!$short) {
1285                                 $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
1286                                         User::getGroupsWithPermission( $action ) );
1287                         }
1288
1289                         if( $groups ) {
1290                                 global $wgLang;
1291                                 $return = array(
1292                                         'badaccess-groups',
1293                                         $wgLang->commaList( $groups ),
1294                                         count( $groups )
1295                                 );
1296                         } else {
1297                                 $return = array( "badaccess-group0" );
1298                         }
1299                         $errors[] = $return;
1300                 }
1301
1302                 # Short-circuit point
1303                 if( $short && count($errors) > 0 ) {
1304                         wfProfileOut( __METHOD__ );
1305                         return $errors;
1306                 }
1307
1308                 // Use getUserPermissionsErrors instead
1309                 if( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1310                         wfProfileOut( __METHOD__ );
1311                         return $result ? array() : array( array( 'badaccess-group0' ) );
1312                 }
1313                 // Check getUserPermissionsErrors hook
1314                 if( !wfRunHooks( 'getUserPermissionsErrors', array(&$this,&$user,$action,&$result) ) ) {
1315                         if( is_array($result) && count($result) && !is_array($result[0]) )
1316                                 $errors[] = $result; # A single array representing an error
1317                         else if( is_array($result) && is_array($result[0]) )
1318                                 $errors = array_merge( $errors, $result ); # A nested array representing multiple errors
1319                         else if( $result !== '' && is_string($result) )
1320                                 $errors[] = array($result); # A string representing a message-id
1321                         else if( $result === false )
1322                                 $errors[] = array('badaccess-group0'); # a generic "We don't want them to do that"
1323                 }
1324                 # Short-circuit point
1325                 if( $short && count($errors) > 0 ) {
1326                         wfProfileOut( __METHOD__ );
1327                         return $errors;
1328                 }
1329                 // Check getUserPermissionsErrorsExpensive hook
1330                 if( $doExpensiveQueries && !wfRunHooks( 'getUserPermissionsErrorsExpensive', array(&$this,&$user,$action,&$result) ) ) {
1331                         if( is_array($result) && count($result) && !is_array($result[0]) )
1332                                 $errors[] = $result; # A single array representing an error
1333                         else if( is_array($result) && is_array($result[0]) )
1334                                 $errors = array_merge( $errors, $result ); # A nested array representing multiple errors
1335                         else if( $result !== '' && is_string($result) )
1336                                 $errors[] = array($result); # A string representing a message-id
1337                         else if( $result === false )
1338                                 $errors[] = array('badaccess-group0'); # a generic "We don't want them to do that"
1339                 }
1340                 # Short-circuit point
1341                 if( $short && count($errors) > 0 ) {
1342                         wfProfileOut( __METHOD__ );
1343                         return $errors;
1344                 }
1345
1346                 # Only 'createaccount' and 'execute' can be performed on
1347                 # special pages, which don't actually exist in the DB.
1348                 $specialOKActions = array( 'createaccount', 'execute' );
1349                 if( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions) ) {
1350                         $errors[] = array('ns-specialprotected');
1351                 }
1352
1353                 # Check $wgNamespaceProtection for restricted namespaces
1354                 if( $this->isNamespaceProtected() ) {
1355                         $ns = $this->getNamespace() == NS_MAIN ?
1356                                 wfMsg( 'nstab-main' ) : $this->getNsText();
1357                         $errors[] = NS_MEDIAWIKI == $this->mNamespace ?
1358                                 array('protectedinterface') : array( 'namespaceprotected',  $ns );
1359                 }
1360
1361                 # Protect css/js subpages of user pages
1362                 # XXX: this might be better using restrictions
1363                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssSubpage()
1364                 #      and $this->userCanEditJsSubpage() from working
1365                 # XXX: right 'editusercssjs' is deprecated, for backward compatibility only
1366                 if( $this->isCssSubpage() && !( $user->isAllowed('editusercssjs') || $user->isAllowed('editusercss') )
1367                         && $action != 'patrol'
1368                         && !preg_match('/^'.preg_quote($user->getName(), '/').'\//', $this->mTextform) )
1369                 {
1370                         $errors[] = array('customcssjsprotected');
1371                 } else if( $this->isJsSubpage() && !( $user->isAllowed('editusercssjs') || $user->isAllowed('edituserjs') )
1372                         && $action != 'patrol'
1373                         && !preg_match('/^'.preg_quote($user->getName(), '/').'\//', $this->mTextform) )
1374                 {
1375                         $errors[] = array('customcssjsprotected');
1376                 }
1377
1378                 # Check against page_restrictions table requirements on this
1379                 # page. The user must possess all required rights for this action.
1380                 foreach( $this->getRestrictions($action) as $right ) {
1381                         // Backwards compatibility, rewrite sysop -> protect
1382                         if( $right == 'sysop' ) {
1383                                 $right = 'protect';
1384                         }
1385                         if( $right != '' && !$user->isAllowed( $right ) ) {
1386                                 // Users with 'editprotected' permission can edit protected pages
1387                                 if( $action=='edit' && $user->isAllowed( 'editprotected' ) ) {
1388                                         // Users with 'editprotected' permission cannot edit protected pages
1389                                         // with cascading option turned on.
1390                                         if( $this->mCascadeRestriction ) {
1391                                                 $errors[] = array( 'protectedpagetext', $right );
1392                                         }
1393                                 } else {
1394                                         $errors[] = array( 'protectedpagetext', $right );
1395                                 }
1396                         }
1397                 }
1398                 # Short-circuit point
1399                 if( $short && count($errors) > 0 ) {
1400                         wfProfileOut( __METHOD__ );
1401                         return $errors;
1402                 }
1403
1404                 if( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1405                         # We /could/ use the protection level on the source page, but it's fairly ugly
1406                         #  as we have to establish a precedence hierarchy for pages included by multiple
1407                         #  cascade-protected pages. So just restrict it to people with 'protect' permission,
1408                         #  as they could remove the protection anyway.
1409                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1410                         # Cascading protection depends on more than this page...
1411                         # Several cascading protected pages may include this page...
1412                         # Check each cascading level
1413                         # This is only for protection restrictions, not for all actions
1414                         if( $cascadingSources > 0 && isset($restrictions[$action]) ) {
1415                                 foreach( $restrictions[$action] as $right ) {
1416                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1417                                         if( $right != '' && !$user->isAllowed( $right ) ) {
1418                                                 $pages = '';
1419                                                 foreach( $cascadingSources as $page )
1420                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1421                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1422                                         }
1423                                 }
1424                         }
1425                 }
1426                 # Short-circuit point
1427                 if( $short && count($errors) > 0 ) {
1428                         wfProfileOut( __METHOD__ );
1429                         return $errors;
1430                 }
1431
1432                 if( $action == 'protect' ) {
1433                         if( $this->getUserPermissionsErrors('edit', $user) != array() ) {
1434                                 $errors[] = array( 'protect-cantedit' ); // If they can't edit, they shouldn't protect.
1435                         }
1436                 }
1437
1438                 if( $action == 'create' ) {
1439                         $title_protection = $this->getTitleProtection();
1440                         if( is_array($title_protection) ) {
1441                                 extract($title_protection); // is this extract() really needed?
1442
1443                                 if( $pt_create_perm == 'sysop' ) {
1444                                         $pt_create_perm = 'protect'; // B/C
1445                                 }
1446                                 if( $pt_create_perm == '' || !$user->isAllowed($pt_create_perm) ) {
1447                                         $errors[] = array( 'titleprotected', User::whoIs($pt_user), $pt_reason );
1448                                 }
1449                         }
1450                 } elseif( $action == 'move' ) {
1451                         // Check for immobile pages
1452                         if( !MWNamespace::isMovable( $this->getNamespace() ) ) {
1453                                 // Specific message for this case
1454                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1455                         } elseif( !$this->isMovable() ) {
1456                                 // Less specific message for rarer cases
1457                                 $errors[] = array( 'immobile-page' );
1458                         }
1459                 } elseif( $action == 'move-target' ) {
1460                         if( !MWNamespace::isMovable( $this->getNamespace() ) ) {
1461                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1462                         } elseif( !$this->isMovable() ) {
1463                                 $errors[] = array( 'immobile-target-page' );
1464                         }
1465                 }
1466
1467                 wfProfileOut( __METHOD__ );
1468                 return $errors;
1469         }
1470
1471         /**
1472          * Is this title subject to title protection?
1473          *
1474          * @return \type{\mixed} An associative array representing any existent title
1475          *   protection, or false if there's none.
1476          */
1477         private function getTitleProtection() {
1478                 // Can't protect pages in special namespaces
1479                 if ( $this->getNamespace() < 0 ) {
1480                         return false;
1481                 }
1482
1483                 // Can't protect pages that exist.
1484                 if ($this->exists()) {
1485                         return false;
1486                 }
1487
1488                 $dbr = wfGetDB( DB_SLAVE );
1489                 $res = $dbr->select( 'protected_titles', '*',
1490                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
1491                         __METHOD__ );
1492
1493                 if ($row = $dbr->fetchRow( $res )) {
1494                         return $row;
1495                 } else {
1496                         return false;
1497                 }
1498         }
1499
1500         /**
1501          * Update the title protection status
1502          *
1503          * @param $create_perm \type{\string} Permission required for creation
1504          * @param $reason \type{\string} Reason for protection
1505          * @param $expiry \type{\string} Expiry timestamp
1506          * @return boolean true
1507          */
1508         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
1509                 global $wgUser,$wgContLang;
1510
1511                 if ($create_perm == implode(',',$this->getRestrictions('create'))
1512                         && $expiry == $this->mRestrictionsExpiry['create']) {
1513                         // No change
1514                         return true;
1515                 }
1516
1517                 list ($namespace, $title) = array( $this->getNamespace(), $this->getDBkey() );
1518
1519                 $dbw = wfGetDB( DB_MASTER );
1520
1521                 $encodedExpiry = Block::encodeExpiry($expiry, $dbw );
1522
1523                 $expiry_description = '';
1524                 if ( $encodedExpiry != 'infinity' ) {
1525                         $expiry_description = ' (' . wfMsgForContent( 'protect-expiring',$wgContLang->timeanddate( $expiry ),
1526                                 $wgContLang->date( $expiry ) , $wgContLang->time( $expiry ) ).')';
1527                 }
1528                 else {
1529                         $expiry_description .= ' (' . wfMsgForContent( 'protect-expiry-indefinite' ).')';
1530                 }
1531
1532                 # Update protection table
1533                 if ($create_perm != '' ) {
1534                         $dbw->replace( 'protected_titles', array(array('pt_namespace', 'pt_title')),
1535                                 array(
1536                                         'pt_namespace' => $namespace,
1537                                         'pt_title' => $title,
1538                                         'pt_create_perm' => $create_perm,
1539                                         'pt_timestamp' => Block::encodeExpiry(wfTimestampNow(), $dbw),
1540                                         'pt_expiry' => $encodedExpiry,
1541                                         'pt_user' => $wgUser->getId(),
1542                                         'pt_reason' => $reason,
1543                                 ), __METHOD__
1544                         );
1545                 } else {
1546                         $dbw->delete( 'protected_titles', array( 'pt_namespace' => $namespace,
1547                                 'pt_title' => $title ), __METHOD__ );
1548                 }
1549                 # Update the protection log
1550                 if( $dbw->affectedRows() ) {
1551                         $log = new LogPage( 'protect' );
1552
1553                         if( $create_perm ) {
1554                                 $params = array("[create=$create_perm] $expiry_description",'');
1555                                 $log->addEntry( ( isset( $this->mRestrictions['create'] ) && $this->mRestrictions['create'] ) ? 'modify' : 'protect', $this, trim( $reason ), $params );
1556                         } else {
1557                                 $log->addEntry( 'unprotect', $this, $reason );
1558                         }
1559                 }
1560
1561                 return true;
1562         }
1563
1564         /**
1565          * Remove any title protection due to page existing
1566          */
1567         public function deleteTitleProtection() {
1568                 $dbw = wfGetDB( DB_MASTER );
1569
1570                 $dbw->delete( 'protected_titles',
1571                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
1572                         __METHOD__ );
1573         }
1574
1575         /**
1576          * Would anybody with sufficient privileges be able to move this page?
1577          * Some pages just aren't movable.
1578          *
1579          * @return \type{\bool} TRUE or FALSE
1580          */
1581         public function isMovable() {
1582                 return MWNamespace::isMovable( $this->getNamespace() ) && $this->getInterwiki() == '';
1583         }
1584
1585         /**
1586          * Can $wgUser read this page?
1587          *
1588          * @return \type{\bool}
1589          * @todo fold these checks into userCan()
1590          */
1591         public function userCanRead() {
1592                 global $wgUser, $wgGroupPermissions;
1593
1594                 static $useShortcut = null;
1595
1596                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
1597                 if( is_null( $useShortcut ) ) {
1598                         global $wgRevokePermissions;
1599                         $useShortcut = true;
1600                         if( empty( $wgGroupPermissions['*']['read'] ) ) {
1601                                 # Not a public wiki, so no shortcut
1602                                 $useShortcut = false;
1603                         } elseif( !empty( $wgRevokePermissions ) ) {
1604                                 /*
1605                                  * Iterate through each group with permissions being revoked (key not included since we don't care
1606                                  * what the group name is), then check if the read permission is being revoked. If it is, then
1607                                  * we don't use the shortcut below since the user might not be able to read, even though anon
1608                                  * reading is allowed.
1609                                  */
1610                                 foreach( $wgRevokePermissions as $perms ) {
1611                                         if( !empty( $perms['read'] ) ) {
1612                                                 # We might be removing the read right from the user, so no shortcut
1613                                                 $useShortcut = false;
1614                                                 break;
1615                                         }
1616                                 }
1617                         }
1618                 }
1619
1620                 $result = null;
1621                 wfRunHooks( 'userCan', array( &$this, &$wgUser, 'read', &$result ) );
1622                 if ( $result !== null ) {
1623                         return $result;
1624                 }
1625
1626                 # Shortcut for public wikis, allows skipping quite a bit of code
1627                 if ( $useShortcut )
1628                         return true;
1629
1630                 if( $wgUser->isAllowed( 'read' ) ) {
1631                         return true;
1632                 } else {
1633                         global $wgWhitelistRead;
1634
1635                         /**
1636                          * Always grant access to the login page.
1637                          * Even anons need to be able to log in.
1638                         */
1639                         if( $this->isSpecial( 'Userlogin' ) || $this->isSpecial( 'Resetpass' ) ) {
1640                                 return true;
1641                         }
1642
1643                         /**
1644                          * Bail out if there isn't whitelist
1645                          */
1646                         if( !is_array($wgWhitelistRead) ) {
1647                                 return false;
1648                         }
1649
1650                         /**
1651                          * Check for explicit whitelisting
1652                          */
1653                         $name = $this->getPrefixedText();
1654                         $dbName = $this->getPrefixedDBKey();
1655                         // Check with and without underscores
1656                         if( in_array($name,$wgWhitelistRead,true) || in_array($dbName,$wgWhitelistRead,true) )
1657                                 return true;
1658
1659                         /**
1660                          * Old settings might have the title prefixed with
1661                          * a colon for main-namespace pages
1662                          */
1663                         if( $this->getNamespace() == NS_MAIN ) {
1664                                 if( in_array( ':' . $name, $wgWhitelistRead ) )
1665                                         return true;
1666                         }
1667
1668                         /**
1669                          * If it's a special page, ditch the subpage bit
1670                          * and check again
1671                          */
1672                         if( $this->getNamespace() == NS_SPECIAL ) {
1673                                 $name = $this->getDBkey();
1674                                 list( $name, /* $subpage */) = SpecialPage::resolveAliasWithSubpage( $name );
1675                                 if ( $name === false ) {
1676                                         # Invalid special page, but we show standard login required message
1677                                         return false;
1678                                 }
1679
1680                                 $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
1681                                 if( in_array( $pure, $wgWhitelistRead, true ) )
1682                                         return true;
1683                         }
1684
1685                 }
1686                 return false;
1687         }
1688
1689         /**
1690          * Is this a talk page of some sort?
1691          *
1692          * @return \type{\bool}
1693          */
1694         public function isTalkPage() {
1695                 return MWNamespace::isTalk( $this->getNamespace() );
1696         }
1697
1698         /**
1699          * Is this a subpage?
1700          *
1701          * @return \type{\bool}
1702          */
1703         public function isSubpage() {
1704                 return MWNamespace::hasSubpages( $this->mNamespace )
1705                         ? strpos( $this->getText(), '/' ) !== false
1706                         : false;
1707         }
1708
1709         /**
1710          * Does this have subpages?  (Warning, usually requires an extra DB query.)
1711          *
1712          * @return \type{\bool}
1713          */
1714         public function hasSubpages() {
1715                 if( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1716                         # Duh
1717                         return false;
1718                 }
1719
1720                 # We dynamically add a member variable for the purpose of this method
1721                 # alone to cache the result.  There's no point in having it hanging
1722                 # around uninitialized in every Title object; therefore we only add it
1723                 # if needed and don't declare it statically.
1724                 if( isset( $this->mHasSubpages ) ) {
1725                         return $this->mHasSubpages;
1726                 }
1727
1728                 $subpages = $this->getSubpages( 1 );
1729                 if( $subpages instanceof TitleArray )
1730                         return $this->mHasSubpages = (bool)$subpages->count();
1731                 return $this->mHasSubpages = false;
1732         }
1733
1734         /**
1735          * Get all subpages of this page.
1736          *
1737          * @param $limit Maximum number of subpages to fetch; -1 for no limit
1738          * @return mixed TitleArray, or empty array if this page's namespace
1739          *  doesn't allow subpages
1740          */
1741         public function getSubpages( $limit = -1 ) {
1742                 if( !MWNamespace::hasSubpages( $this->getNamespace() ) )
1743                         return array();
1744
1745                 $dbr = wfGetDB( DB_SLAVE );
1746                 $conds['page_namespace'] = $this->getNamespace();
1747                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
1748                 $options = array();
1749                 if( $limit > -1 )
1750                         $options['LIMIT'] = $limit;
1751                 return $this->mSubpages = TitleArray::newFromResult(
1752                         $dbr->select( 'page',
1753                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
1754                                 $conds,
1755                                 __METHOD__,
1756                                 $options
1757                         )
1758                 );
1759         }
1760
1761         /**
1762          * Could this page contain custom CSS or JavaScript, based
1763          * on the title?
1764          *
1765          * @return \type{\bool}
1766          */
1767         public function isCssOrJsPage() {
1768                 return $this->mNamespace == NS_MEDIAWIKI
1769                         && preg_match( '!\.(?:css|js)$!u', $this->mTextform ) > 0;
1770         }
1771
1772         /**
1773          * Is this a .css or .js subpage of a user page?
1774          * @return \type{\bool}
1775          */
1776         public function isCssJsSubpage() {
1777                 return ( NS_USER == $this->mNamespace and preg_match("/\\/.*\\.(?:css|js)$/", $this->mTextform ) );
1778         }
1779
1780         /**
1781          * Is this a *valid* .css or .js subpage of a user page?
1782          * Check that the corresponding skin exists
1783          *
1784          * @return \type{\bool}
1785          */
1786         public function isValidCssJsSubpage() {
1787                 if ( $this->isCssJsSubpage() ) {
1788                         $name = $this->getSkinFromCssJsSubpage();
1789                         if ( $name == 'common' ) return true;
1790                         $skinNames = Skin::getSkinNames();
1791                         return array_key_exists( $name, $skinNames );
1792                 } else {
1793                         return false;
1794                 }
1795         }
1796
1797         /**
1798          * Trim down a .css or .js subpage title to get the corresponding skin name
1799          *
1800          * @return string containing skin name from .css or .js subpage title
1801          */
1802         public function getSkinFromCssJsSubpage() {
1803                 $subpage = explode( '/', $this->mTextform );
1804                 $subpage = $subpage[ count( $subpage ) - 1 ];
1805                 return( str_replace( array( '.css', '.js' ), array( '', '' ), $subpage ) );
1806         }
1807
1808         /**
1809          * Is this a .css subpage of a user page?
1810          *
1811          * @return \type{\bool}
1812          */
1813         public function isCssSubpage() {
1814                 return ( NS_USER == $this->mNamespace && preg_match("/\\/.*\\.css$/", $this->mTextform ) );
1815         }
1816
1817         /**
1818          * Is this a .js subpage of a user page?
1819          *
1820          * @return \type{\bool}
1821          */
1822         public function isJsSubpage() {
1823                 return ( NS_USER == $this->mNamespace && preg_match("/\\/.*\\.js$/", $this->mTextform ) );
1824         }
1825
1826         /**
1827          * Protect css subpages of user pages: can $wgUser edit
1828          * this page?
1829          *
1830          * @return \type{\bool}
1831          * @todo XXX: this might be better using restrictions
1832          */
1833         public function userCanEditCssSubpage() {
1834                 global $wgUser;
1835                 return ( ( $wgUser->isAllowed('editusercssjs') && $wgUser->isAllowed('editusercss') )
1836                         || preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1837         }
1838         /**
1839          * Protect js subpages of user pages: can $wgUser edit
1840          * this page?
1841          *
1842          * @return \type{\bool}
1843          * @todo XXX: this might be better using restrictions
1844          */
1845         public function userCanEditJsSubpage() {
1846                 global $wgUser;
1847                 return ( ( $wgUser->isAllowed('editusercssjs') && $wgUser->isAllowed('edituserjs') )
1848                        || preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1849         }
1850
1851         /**
1852          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
1853          *
1854          * @return \type{\bool} If the page is subject to cascading restrictions.
1855          */
1856         public function isCascadeProtected() {
1857                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
1858                 return ( $sources > 0 );
1859         }
1860
1861         /**
1862          * Cascading protection: Get the source of any cascading restrictions on this page.
1863          *
1864          * @param $get_pages \type{\bool} Whether or not to retrieve the actual pages
1865          *        that the restrictions have come from.
1866          * @return \type{\arrayof{mixed title array, restriction array}} Array of the Title
1867          *         objects of the pages from which cascading restrictions have come,
1868          *         false for none, or true if such restrictions exist, but $get_pages was not set.
1869          *         The restriction array is an array of each type, each of which contains a
1870          *         array of unique groups.
1871          */
1872         public function getCascadeProtectionSources( $get_pages = true ) {
1873                 $pagerestrictions = array();
1874
1875                 if ( isset( $this->mCascadeSources ) && $get_pages ) {
1876                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
1877                 } else if ( isset( $this->mHasCascadingRestrictions ) && !$get_pages ) {
1878                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
1879                 }
1880
1881                 wfProfileIn( __METHOD__ );
1882
1883                 $dbr = wfGetDB( DB_SLAVE );
1884
1885                 if ( $this->getNamespace() == NS_FILE ) {
1886                         $tables = array ('imagelinks', 'page_restrictions');
1887                         $where_clauses = array(
1888                                 'il_to' => $this->getDBkey(),
1889                                 'il_from=pr_page',
1890                                 'pr_cascade' => 1 );
1891                 } else {
1892                         $tables = array ('templatelinks', 'page_restrictions');
1893                         $where_clauses = array(
1894                                 'tl_namespace' => $this->getNamespace(),
1895                                 'tl_title' => $this->getDBkey(),
1896                                 'tl_from=pr_page',
1897                                 'pr_cascade' => 1 );
1898                 }
1899
1900                 if ( $get_pages ) {
1901                         $cols = array('pr_page', 'page_namespace', 'page_title', 'pr_expiry', 'pr_type', 'pr_level' );
1902                         $where_clauses[] = 'page_id=pr_page';
1903                         $tables[] = 'page';
1904                 } else {
1905                         $cols = array( 'pr_expiry' );
1906                 }
1907
1908                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
1909
1910                 $sources = $get_pages ? array() : false;
1911                 $now = wfTimestampNow();
1912                 $purgeExpired = false;
1913
1914                 foreach( $res as $row ) {
1915                         $expiry = Block::decodeExpiry( $row->pr_expiry );
1916                         if( $expiry > $now ) {
1917                                 if ($get_pages) {
1918                                         $page_id = $row->pr_page;
1919                                         $page_ns = $row->page_namespace;
1920                                         $page_title = $row->page_title;
1921                                         $sources[$page_id] = Title::makeTitle($page_ns, $page_title);
1922                                         # Add groups needed for each restriction type if its not already there
1923                                         # Make sure this restriction type still exists
1924
1925                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
1926                                                 $pagerestrictions[$row->pr_type] = array();
1927                                         }
1928
1929                                         if ( isset($pagerestrictions[$row->pr_type]) &&
1930                                                         !in_array($row->pr_level, $pagerestrictions[$row->pr_type]) ) {
1931                                                 $pagerestrictions[$row->pr_type][]=$row->pr_level;
1932                                         }
1933                                 } else {
1934                                         $sources = true;
1935                                 }
1936                         } else {
1937                                 // Trigger lazy purge of expired restrictions from the db
1938                                 $purgeExpired = true;
1939                         }
1940                 }
1941                 if( $purgeExpired ) {
1942                         Title::purgeExpiredRestrictions();
1943                 }
1944
1945                 wfProfileOut( __METHOD__ );
1946
1947                 if ( $get_pages ) {
1948                         $this->mCascadeSources = $sources;
1949                         $this->mCascadingRestrictions = $pagerestrictions;
1950                 } else {
1951                         $this->mHasCascadingRestrictions = $sources;
1952                 }
1953                 return array( $sources, $pagerestrictions );
1954         }
1955
1956         /**
1957          * Returns cascading restrictions for the current article
1958          *
1959          * @return Boolean
1960          */
1961         function areRestrictionsCascading() {
1962                 if (!$this->mRestrictionsLoaded) {
1963                         $this->loadRestrictions();
1964                 }
1965
1966                 return $this->mCascadeRestriction;
1967         }
1968
1969         /**
1970          * Loads a string into mRestrictions array
1971          *
1972          * @param $res \type{Resource} restrictions as an SQL result.
1973          * @param $oldFashionedRestrictions string comma-separated list of page
1974          *        restrictions from page table (pre 1.10)
1975          */
1976         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
1977                 $rows = array();
1978                 $dbr = wfGetDB( DB_SLAVE );
1979
1980                 while( $row = $dbr->fetchObject( $res ) ) {
1981                         $rows[] = $row;
1982                 }
1983
1984                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
1985         }
1986
1987         /**
1988          * Compiles list of active page restrictions from both page table (pre 1.10)
1989          * and page_restrictions table
1990          *
1991          * @param $rows array of db result objects
1992          * @param $oldFashionedRestrictions string comma-separated list of page
1993          *        restrictions from page table (pre 1.10)
1994          */
1995         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
1996                 $dbr = wfGetDB( DB_SLAVE );
1997
1998                 $restrictionTypes = $this->getRestrictionTypes();
1999
2000                 foreach( $restrictionTypes as $type ){
2001                         $this->mRestrictions[$type] = array();
2002                         $this->mRestrictionsExpiry[$type] = Block::decodeExpiry('');
2003                 }
2004
2005                 $this->mCascadeRestriction = false;
2006
2007                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2008
2009                 if ( $oldFashionedRestrictions === null ) {
2010                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2011                                 array( 'page_id' => $this->getArticleId() ), __METHOD__ );
2012                 }
2013
2014                 if ($oldFashionedRestrictions != '') {
2015
2016                         foreach( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2017                                 $temp = explode( '=', trim( $restrict ) );
2018                                 if(count($temp) == 1) {
2019                                         // old old format should be treated as edit/move restriction
2020                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2021                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2022                                 } else {
2023                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
2024                                 }
2025                         }
2026
2027                         $this->mOldRestrictions = true;
2028
2029                 }
2030
2031                 if( count($rows) ) {
2032                         # Current system - load second to make them override.
2033                         $now = wfTimestampNow();
2034                         $purgeExpired = false;
2035
2036                         foreach( $rows as $row ) {
2037                                 # Cycle through all the restrictions.
2038
2039                                 // Don't take care of restrictions types that aren't allowed
2040
2041                                 if( !in_array( $row->pr_type, $restrictionTypes ) )
2042                                         continue;
2043
2044                                 // This code should be refactored, now that it's being used more generally,
2045                                 // But I don't really see any harm in leaving it in Block for now -werdna
2046                                 $expiry = Block::decodeExpiry( $row->pr_expiry );
2047
2048                                 // Only apply the restrictions if they haven't expired!
2049                                 if ( !$expiry || $expiry > $now ) {
2050                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2051                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2052
2053                                         $this->mCascadeRestriction |= $row->pr_cascade;
2054                                 } else {
2055                                         // Trigger a lazy purge of expired restrictions
2056                                         $purgeExpired = true;
2057                                 }
2058                         }
2059
2060                         if( $purgeExpired ) {
2061                                 Title::purgeExpiredRestrictions();
2062                         }
2063                 }
2064
2065                 $this->mRestrictionsLoaded = true;
2066         }
2067
2068         /**
2069          * Load restrictions from the page_restrictions table
2070          *
2071          * @param $oldFashionedRestrictions string comma-separated list of page
2072          *        restrictions from page table (pre 1.10)
2073          */
2074         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2075                 if( !$this->mRestrictionsLoaded ) {
2076                         if ($this->exists()) {
2077                                 $dbr = wfGetDB( DB_SLAVE );
2078
2079                                 $res = $dbr->select( 'page_restrictions', '*',
2080                                         array ( 'pr_page' => $this->getArticleId() ), __METHOD__ );
2081
2082                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2083                         } else {
2084                                 $title_protection = $this->getTitleProtection();
2085
2086                                 if (is_array($title_protection)) {
2087                                         extract($title_protection);
2088
2089                                         $now = wfTimestampNow();
2090                                         $expiry = Block::decodeExpiry($pt_expiry);
2091
2092                                         if (!$expiry || $expiry > $now) {
2093                                                 // Apply the restrictions
2094                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2095                                                 $this->mRestrictions['create'] = explode(',', trim($pt_create_perm) );
2096                                         } else { // Get rid of the old restrictions
2097                                                 Title::purgeExpiredRestrictions();
2098                                         }
2099                                 } else {
2100                                         $this->mRestrictionsExpiry['create'] = Block::decodeExpiry('');
2101                                 }
2102                                 $this->mRestrictionsLoaded = true;
2103                         }
2104                 }
2105         }
2106
2107         /**
2108          * Purge expired restrictions from the page_restrictions table
2109          */
2110         static function purgeExpiredRestrictions() {
2111                 $dbw = wfGetDB( DB_MASTER );
2112                 $dbw->delete( 'page_restrictions',
2113                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2114                         __METHOD__ );
2115
2116                 $dbw->delete( 'protected_titles',
2117                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2118                         __METHOD__ );
2119         }
2120
2121         /**
2122          * Accessor/initialisation for mRestrictions
2123          *
2124          * @param $action \type{\string} action that permission needs to be checked for
2125          * @return \type{\arrayof{\string}} the array of groups allowed to edit this article
2126          */
2127         public function getRestrictions( $action ) {
2128                 if( !$this->mRestrictionsLoaded ) {
2129                         $this->loadRestrictions();
2130                 }
2131                 return isset( $this->mRestrictions[$action] )
2132                                 ? $this->mRestrictions[$action]
2133                                 : array();
2134         }
2135
2136         /**
2137          * Get the expiry time for the restriction against a given action
2138          *
2139          * @return 14-char timestamp, or 'infinity' if the page is protected forever
2140          *      or not protected at all, or false if the action is not recognised.
2141          */
2142         public function getRestrictionExpiry( $action ) {
2143                 if( !$this->mRestrictionsLoaded ) {
2144                         $this->loadRestrictions();
2145                 }
2146                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2147         }
2148
2149         /**
2150          * Is there a version of this page in the deletion archive?
2151          *
2152          * @return \type{\int} the number of archived revisions
2153          */
2154         public function isDeleted() {
2155                 if( $this->getNamespace() < 0 ) {
2156                         $n = 0;
2157                 } else {
2158                         $dbr = wfGetDB( DB_SLAVE );
2159                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2160                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2161                                 __METHOD__
2162                         );
2163                         if( $this->getNamespace() == NS_FILE ) {
2164                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2165                                         array( 'fa_name' => $this->getDBkey() ),
2166                                         __METHOD__
2167                                 );
2168                         }
2169                 }
2170                 return (int)$n;
2171         }
2172
2173         /**
2174          * Is there a version of this page in the deletion archive?
2175          *
2176          * @return Boolean
2177          */
2178         public function isDeletedQuick() {
2179                 if( $this->getNamespace() < 0 ) {
2180                         return false;
2181                 }
2182                 $dbr = wfGetDB( DB_SLAVE );
2183                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2184                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2185                         __METHOD__
2186                 );
2187                 if( !$deleted && $this->getNamespace() == NS_FILE ) {
2188                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2189                                 array( 'fa_name' => $this->getDBkey() ),
2190                                 __METHOD__
2191                         );
2192                 }
2193                 return $deleted;
2194         }
2195
2196         /**
2197          * Get the article ID for this Title from the link cache,
2198          * adding it if necessary
2199          *
2200          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select
2201          *  for update
2202          * @return \type{\int} the ID
2203          */
2204         public function getArticleID( $flags = 0 ) {
2205                 if( $this->getNamespace() < 0 ) {
2206                         return $this->mArticleID = 0;
2207                 }
2208                 $linkCache = LinkCache::singleton();
2209                 if( $flags & GAID_FOR_UPDATE ) {
2210                         $oldUpdate = $linkCache->forUpdate( true );
2211                         $linkCache->clearLink( $this );
2212                         $this->mArticleID = $linkCache->addLinkObj( $this );
2213                         $linkCache->forUpdate( $oldUpdate );
2214                 } else {
2215                         if( -1 == $this->mArticleID ) {
2216                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2217                         }
2218                 }
2219                 return $this->mArticleID;
2220         }
2221
2222         /**
2223          * Is this an article that is a redirect page?
2224          * Uses link cache, adding it if necessary
2225          *
2226          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select for update
2227          * @return \type{\bool}
2228          */
2229         public function isRedirect( $flags = 0 ) {
2230                 if( !is_null($this->mRedirect) )
2231                         return $this->mRedirect;
2232                 # Calling getArticleID() loads the field from cache as needed
2233                 if( !$this->getArticleID($flags) ) {
2234                         return $this->mRedirect = false;
2235                 }
2236                 $linkCache = LinkCache::singleton();
2237                 $this->mRedirect = (bool)$linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2238
2239                 return $this->mRedirect;
2240         }
2241
2242         /**
2243          * What is the length of this page?
2244          * Uses link cache, adding it if necessary
2245          *
2246          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select for update
2247          * @return \type{\bool}
2248          */
2249         public function getLength( $flags = 0 ) {
2250                 if( $this->mLength != -1 )
2251                         return $this->mLength;
2252                 # Calling getArticleID() loads the field from cache as needed
2253                 if( !$this->getArticleID($flags) ) {
2254                         return $this->mLength = 0;
2255                 }
2256                 $linkCache = LinkCache::singleton();
2257                 $this->mLength = intval( $linkCache->getGoodLinkFieldObj( $this, 'length' ) );
2258
2259                 return $this->mLength;
2260         }
2261
2262         /**
2263          * What is the page_latest field for this page?
2264          *
2265          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select for update
2266          * @return \type{\int} or false if the page doesn't exist
2267          */
2268         public function getLatestRevID( $flags = 0 ) {
2269                 if( $this->mLatestID !== false )
2270                         return $this->mLatestID;
2271
2272                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB(DB_MASTER) : wfGetDB(DB_SLAVE);
2273                 $this->mLatestID = (int)$db->selectField(
2274                         'page', 'page_latest', $this->pageCond(), __METHOD__ );
2275                 return $this->mLatestID;
2276         }
2277
2278         /**
2279          * This clears some fields in this object, and clears any associated
2280          * keys in the "bad links" section of the link cache.
2281          *
2282          * - This is called from Article::insertNewArticle() to allow
2283          * loading of the new page_id. It's also called from
2284          * Article::doDeleteArticle()
2285          *
2286          * @param $newid \type{\int} the new Article ID
2287          */
2288         public function resetArticleID( $newid ) {
2289                 $linkCache = LinkCache::singleton();
2290                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
2291
2292                 if ( $newid === false ) {
2293                         $this->mArticleID = -1;
2294                 } else {
2295                         $this->mArticleID = intval( $newid );
2296                 }
2297                 $this->mRestrictionsLoaded = false;
2298                 $this->mRestrictions = array();
2299                 $this->mRedirect = null;
2300                 $this->mLength = -1;
2301                 $this->mLatestID = false;
2302         }
2303
2304         /**
2305          * Updates page_touched for this page; called from LinksUpdate.php
2306          *
2307          * @return \type{\bool} true if the update succeded
2308          */
2309         public function invalidateCache() {
2310                 if( wfReadOnly() ) {
2311                         return;
2312                 }
2313                 $dbw = wfGetDB( DB_MASTER );
2314                 $success = $dbw->update( 'page',
2315                         array( 'page_touched' => $dbw->timestamp() ),
2316                         $this->pageCond(),
2317                         __METHOD__
2318                 );
2319                 HTMLFileCache::clearFileCache( $this );
2320                 return $success;
2321         }
2322
2323         /**
2324          * Prefix some arbitrary text with the namespace or interwiki prefix
2325          * of this object
2326          *
2327          * @param $name \type{\string} the text
2328          * @return \type{\string} the prefixed text
2329          * @private
2330          */
2331         /* private */ function prefix( $name ) {
2332                 $p = '';
2333                 if ( $this->mInterwiki != '' ) {
2334                         $p = $this->mInterwiki . ':';
2335                 }
2336                 if ( 0 != $this->mNamespace ) {
2337                         $p .= $this->getNsText() . ':';
2338                 }
2339                 return $p . $name;
2340         }
2341
2342         /**
2343          * Returns a simple regex that will match on characters and sequences invalid in titles.
2344          * Note that this doesn't pick up many things that could be wrong with titles, but that
2345          * replacing this regex with something valid will make many titles valid.
2346          *
2347          * @return string regex string
2348          */
2349         static function getTitleInvalidRegex() {
2350                 static $rxTc = false;
2351                 if( !$rxTc ) {
2352                         # Matching titles will be held as illegal.
2353                         $rxTc = '/' .
2354                                 # Any character not allowed is forbidden...
2355                                 '[^' . Title::legalChars() . ']' .
2356                                 # URL percent encoding sequences interfere with the ability
2357                                 # to round-trip titles -- you can't link to them consistently.
2358                                 '|%[0-9A-Fa-f]{2}' .
2359                                 # XML/HTML character references produce similar issues.
2360                                 '|&[A-Za-z0-9\x80-\xff]+;' .
2361                                 '|&#[0-9]+;' .
2362                                 '|&#x[0-9A-Fa-f]+;' .
2363                                 '/S';
2364                 }
2365
2366                 return $rxTc;
2367         }
2368
2369         /**
2370          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
2371          *
2372          * @param $text string containing title to capitalize
2373          * @param $ns int namespace index, defaults to NS_MAIN
2374          * @return String containing capitalized title
2375          */
2376         public static function capitalize( $text, $ns = NS_MAIN ) {
2377                 global $wgContLang;
2378
2379                 if ( MWNamespace::isCapitalized( $ns ) )
2380                         return $wgContLang->ucfirst( $text );
2381                 else
2382                         return $text;
2383         }
2384
2385         /**
2386          * Secure and split - main initialisation function for this object
2387          *
2388          * Assumes that mDbkeyform has been set, and is urldecoded
2389          * and uses underscores, but not otherwise munged.  This function
2390          * removes illegal characters, splits off the interwiki and
2391          * namespace prefixes, sets the other forms, and canonicalizes
2392          * everything.
2393          *
2394          * @return \type{\bool} true on success
2395          */
2396         private function secureAndSplit() {
2397                 global $wgContLang, $wgLocalInterwiki;
2398
2399                 # Initialisation
2400                 $rxTc = self::getTitleInvalidRegex();
2401
2402                 $this->mInterwiki = $this->mFragment = '';
2403                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2404
2405                 $dbkey = $this->mDbkeyform;
2406
2407                 # Strip Unicode bidi override characters.
2408                 # Sometimes they slip into cut-n-pasted page titles, where the
2409                 # override chars get included in list displays.
2410                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
2411
2412                 # Clean up whitespace
2413                 # Note: use of the /u option on preg_replace here will cause
2414                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
2415                 # conveniently disabling them.
2416                 #
2417                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
2418                 $dbkey = trim( $dbkey, '_' );
2419
2420                 if ( $dbkey == '' ) {
2421                         return false;
2422                 }
2423
2424                 if( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2425                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2426                         return false;
2427                 }
2428
2429                 $this->mDbkeyform = $dbkey;
2430
2431                 # Initial colon indicates main namespace rather than specified default
2432                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
2433                 if ( ':' == $dbkey{0} ) {
2434                         $this->mNamespace = NS_MAIN;
2435                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
2436                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
2437                 }
2438
2439                 # Namespace or interwiki prefix
2440                 $firstPass = true;
2441                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
2442                 do {
2443                         $m = array();
2444                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
2445                                 $p = $m[1];
2446                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
2447                                         # Ordinary namespace
2448                                         $dbkey = $m[2];
2449                                         $this->mNamespace = $ns;
2450                                         # For Talk:X pages, check if X has a "namespace" prefix
2451                                         if( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
2452                                                 if( $wgContLang->getNsIndex( $x[1] ) )
2453                                                         return false; # Disallow Talk:File:x type titles...
2454                                                 else if( Interwiki::isValidInterwiki( $x[1] ) )
2455                                                         return false; # Disallow Talk:Interwiki:x type titles...
2456                                         }
2457                                 } elseif( Interwiki::isValidInterwiki( $p ) ) {
2458                                         if( !$firstPass ) {
2459                                                 # Can't make a local interwiki link to an interwiki link.
2460                                                 # That's just crazy!
2461                                                 return false;
2462                                         }
2463
2464                                         # Interwiki link
2465                                         $dbkey = $m[2];
2466                                         $this->mInterwiki = $wgContLang->lc( $p );
2467
2468                                         # Redundant interwiki prefix to the local wiki
2469                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
2470                                                 if( $dbkey == '' ) {
2471                                                         # Can't have an empty self-link
2472                                                         return false;
2473                                                 }
2474                                                 $this->mInterwiki = '';
2475                                                 $firstPass = false;
2476                                                 # Do another namespace split...
2477                                                 continue;
2478                                         }
2479
2480                                         # If there's an initial colon after the interwiki, that also
2481                                         # resets the default namespace
2482                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
2483                                                 $this->mNamespace = NS_MAIN;
2484                                                 $dbkey = substr( $dbkey, 1 );
2485                                         }
2486                                 }
2487                                 # If there's no recognized interwiki or namespace,
2488                                 # then let the colon expression be part of the title.
2489                         }
2490                         break;
2491                 } while( true );
2492
2493                 # We already know that some pages won't be in the database!
2494                 #
2495                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
2496                         $this->mArticleID = 0;
2497                 }
2498                 $fragment = strstr( $dbkey, '#' );
2499                 if ( false !== $fragment ) {
2500                         $this->setFragment( $fragment );
2501                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
2502                         # remove whitespace again: prevents "Foo_bar_#"
2503                         # becoming "Foo_bar_"
2504                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
2505                 }
2506
2507                 # Reject illegal characters.
2508                 #
2509                 if( preg_match( $rxTc, $dbkey ) ) {
2510                         return false;
2511                 }
2512
2513                 /**
2514                  * Pages with "/./" or "/../" appearing in the URLs will often be un-
2515                  * reachable due to the way web browsers deal with 'relative' URLs.
2516                  * Also, they conflict with subpage syntax.  Forbid them explicitly.
2517                  */
2518                 if ( strpos( $dbkey, '.' ) !== false &&
2519                      ( $dbkey === '.' || $dbkey === '..' ||
2520                        strpos( $dbkey, './' ) === 0  ||
2521                        strpos( $dbkey, '../' ) === 0 ||
2522                        strpos( $dbkey, '/./' ) !== false ||
2523                        strpos( $dbkey, '/../' ) !== false  ||
2524                        substr( $dbkey, -2 ) == '/.' ||
2525                        substr( $dbkey, -3 ) == '/..' ) )
2526                 {
2527                         return false;
2528                 }
2529
2530                 /**
2531                  * Magic tilde sequences? Nu-uh!
2532                  */
2533                 if( strpos( $dbkey, '~~~' ) !== false ) {
2534                         return false;
2535                 }
2536
2537                 /**
2538                  * Limit the size of titles to 255 bytes.
2539                  * This is typically the size of the underlying database field.
2540                  * We make an exception for special pages, which don't need to be stored
2541                  * in the database, and may edge over 255 bytes due to subpage syntax
2542                  * for long titles, e.g. [[Special:Block/Long name]]
2543                  */
2544                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
2545                   strlen( $dbkey ) > 512 )
2546                 {
2547                         return false;
2548                 }
2549
2550                 /**
2551                  * Normally, all wiki links are forced to have
2552                  * an initial capital letter so [[foo]] and [[Foo]]
2553                  * point to the same place.
2554                  *
2555                  * Don't force it for interwikis, since the other
2556                  * site might be case-sensitive.
2557                  */
2558                 $this->mUserCaseDBKey = $dbkey;
2559                 if(  $this->mInterwiki == '') {
2560                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
2561                 }
2562
2563                 /**
2564                  * Can't make a link to a namespace alone...
2565                  * "empty" local links can only be self-links
2566                  * with a fragment identifier.
2567                  */
2568                 if( $dbkey == '' &&
2569                         $this->mInterwiki == '' &&
2570                         $this->mNamespace != NS_MAIN ) {
2571                         return false;
2572                 }
2573                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
2574                 // IP names are not allowed for accounts, and can only be referring to
2575                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
2576                 // there are numerous ways to present the same IP. Having sp:contribs scan
2577                 // them all is silly and having some show the edits and others not is
2578                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
2579                 $dbkey = ($this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK) ?
2580                         IP::sanitizeIP( $dbkey ) : $dbkey;
2581                 // Any remaining initial :s are illegal.
2582                 if ( $dbkey !== '' && ':' == $dbkey{0} ) {
2583                         return false;
2584                 }
2585
2586                 # Fill fields
2587                 $this->mDbkeyform = $dbkey;
2588                 $this->mUrlform = wfUrlencode( $dbkey );
2589
2590                 $this->mTextform = str_replace( '_', ' ', $dbkey );
2591
2592                 return true;
2593         }
2594
2595         /**
2596          * Set the fragment for this title. Removes the first character from the
2597          * specified fragment before setting, so it assumes you're passing it with
2598          * an initial "#".
2599          *
2600          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
2601          * Still in active use privately.
2602          *
2603          * @param $fragment \type{\string} text
2604          */
2605         public function setFragment( $fragment ) {
2606                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
2607         }
2608
2609         /**
2610          * Get a Title object associated with the talk page of this article
2611          *
2612          * @return \type{Title} the object for the talk page
2613          */
2614         public function getTalkPage() {
2615                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
2616         }
2617
2618         /**
2619          * Get a title object associated with the subject page of this
2620          * talk page
2621          *
2622          * @return \type{Title} the object for the subject page
2623          */
2624         public function getSubjectPage() {
2625                 // Is this the same title?
2626                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
2627                 if( $this->getNamespace() == $subjectNS ) {
2628                         return $this;
2629                 }
2630                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
2631         }
2632
2633         /**
2634          * Get an array of Title objects linking to this Title
2635          * Also stores the IDs in the link cache.
2636          *
2637          * WARNING: do not use this function on arbitrary user-supplied titles!
2638          * On heavily-used templates it will max out the memory.
2639          *
2640          * @param $options Array: may be FOR UPDATE
2641          * @param $table String: table name
2642          * @param $prefix String: fields prefix
2643          * @return \type{\arrayof{Title}} the Title objects linking here
2644          */
2645         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
2646                 $linkCache = LinkCache::singleton();
2647
2648                 if ( count( $options ) > 0 ) {
2649                         $db = wfGetDB( DB_MASTER );
2650                 } else {
2651                         $db = wfGetDB( DB_SLAVE );
2652                 }
2653
2654                 $res = $db->select( array( 'page', $table ),
2655                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect' ),
2656                         array(
2657                                 "{$prefix}_from=page_id",
2658                                 "{$prefix}_namespace" => $this->getNamespace(),
2659                                 "{$prefix}_title"     => $this->getDBkey() ),
2660                         __METHOD__,
2661                         $options );
2662
2663                 $retVal = array();
2664                 if ( $db->numRows( $res ) ) {
2665                         foreach( $res as $row ) {
2666                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
2667                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj, $row->page_len, $row->page_is_redirect );
2668                                         $retVal[] = $titleObj;
2669                                 }
2670                         }
2671                 }
2672                 $db->freeResult( $res );
2673                 return $retVal;
2674         }
2675
2676         /**
2677          * Get an array of Title objects using this Title as a template
2678          * Also stores the IDs in the link cache.
2679          *
2680          * WARNING: do not use this function on arbitrary user-supplied titles!
2681          * On heavily-used templates it will max out the memory.
2682          *
2683          * @param $options Array: may be FOR UPDATE
2684          * @return \type{\arrayof{Title}} the Title objects linking here
2685          */
2686         public function getTemplateLinksTo( $options = array() ) {
2687                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
2688         }
2689
2690         /**
2691          * Get an array of Title objects referring to non-existent articles linked from this page
2692          *
2693          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
2694          * @return \type{\arrayof{Title}} the Title objects
2695          */
2696         public function getBrokenLinksFrom() {
2697                 if ( $this->getArticleId() == 0 ) {
2698                         # All links from article ID 0 are false positives
2699                         return array();
2700                 }
2701
2702                 $dbr = wfGetDB( DB_SLAVE );
2703                 $res = $dbr->select(
2704                         array( 'page', 'pagelinks' ),
2705                         array( 'pl_namespace', 'pl_title' ),
2706                         array(
2707                                 'pl_from' => $this->getArticleId(),
2708                                 'page_namespace IS NULL'
2709                         ),
2710                         __METHOD__, array(),
2711                         array(
2712                                 'page' => array(
2713                                         'LEFT JOIN',
2714                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
2715                                 )
2716                         )
2717                 );
2718
2719                 $retVal = array();
2720                 foreach( $res as $row ) {
2721                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
2722                 }
2723                 return $retVal;
2724         }
2725
2726
2727         /**
2728          * Get a list of URLs to purge from the Squid cache when this
2729          * page changes
2730          *
2731          * @return \type{\arrayof{\string}} the URLs
2732          */
2733         public function getSquidURLs() {
2734                 global $wgContLang;
2735
2736                 $urls = array(
2737                         $this->getInternalURL(),
2738                         $this->getInternalURL( 'action=history' )
2739                 );
2740
2741                 // purge variant urls as well
2742                 if($wgContLang->hasVariants()){
2743                         $variants = $wgContLang->getVariants();
2744                         foreach($variants as $vCode){
2745                                 if($vCode==$wgContLang->getCode()) continue; // we don't want default variant
2746                                 $urls[] = $this->getInternalURL('',$vCode);
2747                         }
2748                 }
2749
2750                 return $urls;
2751         }
2752
2753         /**
2754          * Purge all applicable Squid URLs
2755          */
2756         public function purgeSquid() {
2757                 global $wgUseSquid;
2758                 if ( $wgUseSquid ) {
2759                         $urls = $this->getSquidURLs();
2760                         $u = new SquidUpdate( $urls );
2761                         $u->doUpdate();
2762                 }
2763         }
2764
2765         /**
2766          * Move this page without authentication
2767          *
2768          * @param $nt \type{Title} the new page Title
2769          * @return \type{\mixed} true on success, getUserPermissionsErrors()-like array on failure
2770          */
2771         public function moveNoAuth( &$nt ) {
2772                 return $this->moveTo( $nt, false );
2773         }
2774
2775         /**
2776          * Check whether a given move operation would be valid.
2777          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
2778          *
2779          * @param $nt \type{Title} the new title
2780          * @param $auth \type{\bool} indicates whether $wgUser's permissions
2781          *  should be checked
2782          * @param $reason \type{\string} is the log summary of the move, used for spam checking
2783          * @return \type{\mixed} True on success, getUserPermissionsErrors()-like array on failure
2784          */
2785         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
2786                 global $wgUser;
2787
2788                 $errors = array();
2789                 if( !$nt ) {
2790                         // Normally we'd add this to $errors, but we'll get
2791                         // lots of syntax errors if $nt is not an object
2792                         return array(array('badtitletext'));
2793                 }
2794                 if( $this->equals( $nt ) ) {
2795                         $errors[] = array('selfmove');
2796                 }
2797                 if( !$this->isMovable() ) {
2798                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
2799                 }
2800                 if ( $nt->getInterwiki() != '' ) {
2801                         $errors[] = array( 'immobile-target-namespace-iw' );
2802                 }
2803                 if ( !$nt->isMovable() ) {
2804                         $errors[] = array('immobile-target-namespace', $nt->getNsText() );
2805                 }
2806
2807                 $oldid = $this->getArticleID();
2808                 $newid = $nt->getArticleID();
2809
2810                 if ( strlen( $nt->getDBkey() ) < 1 ) {
2811                         $errors[] = array('articleexists');
2812                 }
2813                 if ( ( $this->getDBkey() == '' ) ||
2814                          ( !$oldid ) ||
2815                      ( $nt->getDBkey() == '' ) ) {
2816                         $errors[] = array('badarticleerror');
2817                 }
2818
2819                 // Image-specific checks
2820                 if( $this->getNamespace() == NS_FILE ) {
2821                         $file = wfLocalFile( $this );
2822                         if( $file->exists() ) {
2823                                 if( $nt->getNamespace() != NS_FILE ) {
2824                                         $errors[] = array('imagenocrossnamespace');
2825                                 }
2826                                 if( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
2827                                         $errors[] = array('imageinvalidfilename');
2828                                 }
2829                                 if( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
2830                                         $errors[] = array('imagetypemismatch');
2831                                 }
2832                         }
2833                         $destfile = wfLocalFile( $nt );
2834                         if( !$wgUser->isAllowed( 'reupload-shared' ) && !$destfile->exists() && wfFindFile( $nt ) ) {
2835                                 $errors[] = array( 'file-exists-sharedrepo' );
2836                         }
2837
2838                 }
2839
2840                 if ( $auth ) {
2841                         $errors = wfMergeErrorArrays( $errors,
2842                                 $this->getUserPermissionsErrors('move', $wgUser),
2843                                 $this->getUserPermissionsErrors('edit', $wgUser),
2844                                 $nt->getUserPermissionsErrors('move-target', $wgUser),
2845                                 $nt->getUserPermissionsErrors('edit', $wgUser) );
2846                 }
2847
2848                 $match = EditPage::matchSummarySpamRegex( $reason );
2849                 if( $match !== false ) {
2850                         // This is kind of lame, won't display nice
2851                         $errors[] = array('spamprotectiontext');
2852                 }
2853
2854                 $err = null;
2855                 if( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
2856                         $errors[] = array('hookaborted', $err);
2857                 }
2858
2859                 # The move is allowed only if (1) the target doesn't exist, or
2860                 # (2) the target is a redirect to the source, and has no history
2861                 # (so we can undo bad moves right after they're done).
2862
2863                 if ( 0 != $newid ) { # Target exists; check for validity
2864                         if ( ! $this->isValidMoveTarget( $nt ) ) {
2865                                 $errors[] = array('articleexists');
2866                         }
2867                 } else {
2868                         $tp = $nt->getTitleProtection();
2869                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
2870                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
2871                                 $errors[] = array('cantmove-titleprotected');
2872                         }
2873                 }
2874                 if(empty($errors))
2875                         return true;
2876                 return $errors;
2877         }
2878
2879         /**
2880          * Move a title to a new location
2881          *
2882          * @param $nt \type{Title} the new title
2883          * @param $auth \type{\bool} indicates whether $wgUser's permissions
2884          *  should be checked
2885          * @param $reason \type{\string} The reason for the move
2886          * @param $createRedirect \type{\bool} Whether to create a redirect from the old title to the new title.
2887          *  Ignored if the user doesn't have the suppressredirect right.
2888          * @return \type{\mixed} true on success, getUserPermissionsErrors()-like array on failure
2889          */
2890         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
2891                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
2892                 if( is_array( $err ) ) {
2893                         return $err;
2894                 }
2895
2896                 // If it is a file, move it first. It is done before all other moving stuff is done because it's hard to revert
2897                 $dbw = wfGetDB( DB_MASTER );
2898                 if( $this->getNamespace() == NS_FILE ) {
2899                         $file = wfLocalFile( $this );
2900                         if( $file->exists() ) {
2901                                 $status = $file->move( $nt );
2902                                 if( !$status->isOk() ) {
2903                                         return $status->getErrorsArray();
2904                                 }
2905                         }
2906                 }
2907
2908                 $pageid = $this->getArticleID();
2909                 $protected = $this->isProtected();
2910                 if( $nt->exists() ) {
2911                         $err = $this->moveOverExistingRedirect( $nt, $reason, $createRedirect );
2912                         $pageCountChange = ($createRedirect ? 0 : -1);
2913                 } else { # Target didn't exist, do normal move.
2914                         $err = $this->moveToNewTitle( $nt, $reason, $createRedirect );
2915                         $pageCountChange = ($createRedirect ? 1 : 0);
2916                 }
2917
2918                 if( is_array( $err ) ) {
2919                         return $err;
2920                 }
2921                 $redirid = $this->getArticleID();
2922
2923                 // Category memberships include a sort key which may be customized.
2924                 // If it's left as the default (the page title), we need to update
2925                 // the sort key to match the new title.
2926                 //
2927                 // Be careful to avoid resetting cl_timestamp, which may disturb
2928                 // time-based lists on some sites.
2929                 //
2930                 // Warning -- if the sort key is *explicitly* set to the old title,
2931                 // we can't actually distinguish it from a default here, and it'll
2932                 // be set to the new title even though it really shouldn't.
2933                 // It'll get corrected on the next edit, but resetting cl_timestamp.
2934                 $dbw->update( 'categorylinks',
2935                         array(
2936                                 'cl_sortkey' => $nt->getPrefixedText(),
2937                                 'cl_timestamp=cl_timestamp' ),
2938                         array(
2939                                 'cl_from' => $pageid,
2940                                 'cl_sortkey' => $this->getPrefixedText() ),
2941                         __METHOD__ );
2942
2943                 if( $protected ) {
2944                         # Protect the redirect title as the title used to be...
2945                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
2946                                 array(
2947                                         'pr_page'    => $redirid,
2948                                         'pr_type'    => 'pr_type',
2949                                         'pr_level'   => 'pr_level',
2950                                         'pr_cascade' => 'pr_cascade',
2951                                         'pr_user'    => 'pr_user',
2952                                         'pr_expiry'  => 'pr_expiry'
2953                                 ),
2954                                 array( 'pr_page' => $pageid ),
2955                                 __METHOD__,
2956                                 array( 'IGNORE' )
2957                         );
2958                         # Update the protection log
2959                         $log = new LogPage( 'protect' );
2960                         $comment = wfMsgForContent( 'prot_1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
2961                         if( $reason ) $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
2962                         $log->addEntry( 'move_prot', $nt, $comment, array($this->getPrefixedText()) ); // FIXME: $params?
2963                 }
2964
2965                 # Update watchlists
2966                 $oldnamespace = $this->getNamespace() & ~1;
2967                 $newnamespace = $nt->getNamespace() & ~1;
2968                 $oldtitle = $this->getDBkey();
2969                 $newtitle = $nt->getDBkey();
2970
2971                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
2972                         WatchedItem::duplicateEntries( $this, $nt );
2973                 }
2974
2975                 # Update search engine
2976                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
2977                 $u->doUpdate();
2978                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
2979                 $u->doUpdate();
2980
2981                 # Update site_stats
2982                 if( $this->isContentPage() && !$nt->isContentPage() ) {
2983                         # No longer a content page
2984                         # Not viewed, edited, removing
2985                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange );
2986                 } elseif( !$this->isContentPage() && $nt->isContentPage() ) {
2987                         # Now a content page
2988                         # Not viewed, edited, adding
2989                         $u = new SiteStatsUpdate( 0, 1, +1, $pageCountChange );
2990                 } elseif( $pageCountChange ) {
2991                         # Redirect added
2992                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
2993                 } else {
2994                         # Nothing special
2995                         $u = false;
2996                 }
2997                 if( $u )
2998                         $u->doUpdate();
2999                 # Update message cache for interface messages
3000                 if( $nt->getNamespace() == NS_MEDIAWIKI ) {
3001                         global $wgMessageCache;
3002
3003                         # @bug 17860: old article can be deleted, if this the case,
3004                         # delete it from message cache
3005                         if ( $this->getArticleID() === 0 ) {
3006                                 $wgMessageCache->replace( $this->getDBkey(), false );
3007                         } else {
3008                                 $oldarticle = new Article( $this );
3009                                 $wgMessageCache->replace( $this->getDBkey(), $oldarticle->getContent() );
3010                         }
3011
3012                         $newarticle = new Article( $nt );
3013                         $wgMessageCache->replace( $nt->getDBkey(), $newarticle->getContent() );
3014                 }
3015
3016                 global $wgUser;
3017                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3018                 return true;
3019         }
3020
3021         /**
3022          * Move page to a title which is at present a redirect to the
3023          * source page
3024          *
3025          * @param $nt \type{Title} the page to move to, which should currently
3026          *  be a redirect
3027          * @param $reason \type{\string} The reason for the move
3028          * @param $createRedirect \type{\bool} Whether to leave a redirect at the old title.
3029          *  Ignored if the user doesn't have the suppressredirect right
3030          */
3031         private function moveOverExistingRedirect( &$nt, $reason = '', $createRedirect = true ) {
3032                 global $wgUseSquid, $wgUser, $wgContLang;
3033
3034                 $comment = wfMsgForContent( '1movedto2_redir', $this->getPrefixedText(), $nt->getPrefixedText() );
3035
3036                 if ( $reason ) {
3037                         $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3038                 }
3039                 # Truncate for whole multibyte characters. +5 bytes for ellipsis
3040                 $comment = $wgContLang->truncate( $comment, 250 );
3041
3042                 $now = wfTimestampNow();
3043                 $newid = $nt->getArticleID();
3044                 $oldid = $this->getArticleID();
3045                 $latest = $this->getLatestRevID();
3046
3047                 $dbw = wfGetDB( DB_MASTER );
3048
3049                 $rcts = $dbw->timestamp( $nt->getEarliestRevTime() );
3050                 $newns = $nt->getNamespace();
3051                 $newdbk = $nt->getDBkey();
3052
3053                 # Delete the old redirect. We don't save it to history since
3054                 # by definition if we've got here it's rather uninteresting.
3055                 # We have to remove it so that the next step doesn't trigger
3056                 # a conflict on the unique namespace+title index...
3057                 $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3058                 if ( !$dbw->cascadingDeletes() ) {
3059                         $dbw->delete( 'revision', array( 'rev_page' => $newid ), __METHOD__ );
3060                         global $wgUseTrackbacks;
3061                         if ($wgUseTrackbacks)
3062                                 $dbw->delete( 'trackbacks', array( 'tb_page' => $newid ), __METHOD__ );
3063                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
3064                         $dbw->delete( 'imagelinks', array( 'il_from' => $newid ), __METHOD__ );
3065                         $dbw->delete( 'categorylinks', array( 'cl_from' => $newid ), __METHOD__ );
3066                         $dbw->delete( 'templatelinks', array( 'tl_from' => $newid ), __METHOD__ );
3067                         $dbw->delete( 'externallinks', array( 'el_from' => $newid ), __METHOD__ );
3068                         $dbw->delete( 'langlinks', array( 'll_from' => $newid ), __METHOD__ );
3069                         $dbw->delete( 'redirect', array( 'rd_from' => $newid ), __METHOD__ );
3070                 }
3071                 // If the redirect was recently created, it may have an entry in recentchanges still
3072                 $dbw->delete( 'recentchanges',
3073                         array( 'rc_timestamp' => $rcts, 'rc_namespace' => $newns, 'rc_title' => $newdbk, 'rc_new' => 1 ),
3074                         __METHOD__
3075                 );
3076
3077                 # Save a null revision in the page's history notifying of the move
3078                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3079                 $nullRevId = $nullRevision->insertOn( $dbw );
3080
3081                 $article = new Article( $this );
3082                 wfRunHooks( 'NewRevisionFromEditComplete', array($article, $nullRevision, $latest, $wgUser) );
3083
3084                 # Change the name of the target page:
3085                 $dbw->update( 'page',
3086                         /* SET */ array(
3087                                 'page_touched'   => $dbw->timestamp($now),
3088                                 'page_namespace' => $nt->getNamespace(),
3089                                 'page_title'     => $nt->getDBkey(),
3090                                 'page_latest'    => $nullRevId,
3091                         ),
3092                         /* WHERE */ array( 'page_id' => $oldid ),
3093                         __METHOD__
3094                 );
3095                 $nt->resetArticleID( $oldid );
3096
3097                 # Recreate the redirect, this time in the other direction.
3098                 if( $createRedirect || !$wgUser->isAllowed('suppressredirect') ) {
3099                         $mwRedir = MagicWord::get( 'redirect' );
3100                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3101                         $redirectArticle = new Article( $this );
3102                         $newid = $redirectArticle->insertOn( $dbw );
3103                         $redirectRevision = new Revision( array(
3104                                 'page'    => $newid,
3105                                 'comment' => $comment,
3106                                 'text'    => $redirectText ) );
3107                         $redirectRevision->insertOn( $dbw );
3108                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3109
3110                         wfRunHooks( 'NewRevisionFromEditComplete', array($redirectArticle, $redirectRevision, false, $wgUser) );
3111
3112                         # Now, we record the link from the redirect to the new title.
3113                         # It should have no other outgoing links...
3114                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
3115                         $dbw->insert( 'pagelinks',
3116                                 array(
3117                                         'pl_from'      => $newid,
3118                                         'pl_namespace' => $nt->getNamespace(),
3119                                         'pl_title'     => $nt->getDBkey() ),
3120                                 __METHOD__ );
3121                         $redirectSuppressed = false;
3122                 } else {
3123                         $this->resetArticleID( 0 );
3124                         $redirectSuppressed = true;
3125                 }
3126
3127                 # Log the move
3128                 $log = new LogPage( 'move' );
3129                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText(), 2 => $redirectSuppressed ) );
3130
3131                 # Purge squid
3132                 if ( $wgUseSquid ) {
3133                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
3134                         $u = new SquidUpdate( $urls );
3135                         $u->doUpdate();
3136                 }
3137
3138         }
3139
3140         /**
3141          * Move page to non-existing title.
3142          *
3143          * @param $nt \type{Title} the new Title
3144          * @param $reason \type{\string} The reason for the move
3145          * @param $createRedirect \type{\bool} Whether to create a redirect from the old title to the new title
3146          *  Ignored if the user doesn't have the suppressredirect right
3147          */
3148         private function moveToNewTitle( &$nt, $reason = '', $createRedirect = true ) {
3149                 global $wgUseSquid, $wgUser, $wgContLang;
3150
3151                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
3152                 if ( $reason ) {
3153                         $comment .= wfMsgExt( 'colon-separator',
3154                                 array( 'escapenoentities', 'content' ) );
3155                         $comment .= $reason;
3156                 }
3157                 # Truncate for whole multibyte characters. +5 bytes for ellipsis
3158                 $comment = $wgContLang->truncate( $comment, 250 );
3159
3160                 $newid = $nt->getArticleID();
3161                 $oldid = $this->getArticleID();
3162                 $latest = $this->getLatestRevId();
3163
3164                 $dbw = wfGetDB( DB_MASTER );
3165                 $now = $dbw->timestamp();
3166
3167                 # Save a null revision in the page's history notifying of the move
3168                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3169                 if ( !is_object( $nullRevision ) ) {
3170                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3171                 }
3172                 $nullRevId = $nullRevision->insertOn( $dbw );
3173
3174                 $article = new Article( $this );
3175                 wfRunHooks( 'NewRevisionFromEditComplete', array($article, $nullRevision, $latest, $wgUser) );
3176
3177                 # Rename page entry
3178                 $dbw->update( 'page',
3179                         /* SET */ array(
3180                                 'page_touched'   => $now,
3181                                 'page_namespace' => $nt->getNamespace(),
3182                                 'page_title'     => $nt->getDBkey(),
3183                                 'page_latest'    => $nullRevId,
3184                         ),
3185                         /* WHERE */ array( 'page_id' => $oldid ),
3186                         __METHOD__
3187                 );
3188                 $nt->resetArticleID( $oldid );
3189
3190                 if( $createRedirect || !$wgUser->isAllowed('suppressredirect') ) {
3191                         # Insert redirect
3192                         $mwRedir = MagicWord::get( 'redirect' );
3193                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3194                         $redirectArticle = new Article( $this );
3195                         $newid = $redirectArticle->insertOn( $dbw );
3196                         $redirectRevision = new Revision( array(
3197                                 'page'    => $newid,
3198                                 'comment' => $comment,
3199                                 'text'    => $redirectText ) );
3200                         $redirectRevision->insertOn( $dbw );
3201                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3202
3203                         wfRunHooks( 'NewRevisionFromEditComplete', array($redirectArticle, $redirectRevision, false, $wgUser) );
3204
3205                         # Record the just-created redirect's linking to the page
3206                         $dbw->insert( 'pagelinks',
3207                                 array(
3208                                         'pl_from'      => $newid,
3209                                         'pl_namespace' => $nt->getNamespace(),
3210                                         'pl_title'     => $nt->getDBkey() ),
3211                                 __METHOD__ );
3212                         $redirectSuppressed = false;
3213                 } else {
3214                         $this->resetArticleID( 0 );
3215                         $redirectSuppressed = true;
3216                 }
3217
3218                 # Log the move
3219                 $log = new LogPage( 'move' );
3220                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText(), 2 => $redirectSuppressed ) );
3221
3222                 # Purge caches as per article creation
3223                 Article::onArticleCreate( $nt );
3224
3225                 # Purge old title from squid
3226                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
3227                 $this->purgeSquid();
3228
3229         }
3230
3231         /**
3232          * Move this page's subpages to be subpages of $nt
3233          *
3234          * @param $nt Title Move target
3235          * @param $auth bool Whether $wgUser's permissions should be checked
3236          * @param $reason string The reason for the move
3237          * @param $createRedirect bool Whether to create redirects from the old subpages to the new ones
3238          *  Ignored if the user doesn't have the 'suppressredirect' right
3239          * @return mixed array with old page titles as keys, and strings (new page titles) or
3240          *  arrays (errors) as values, or an error array with numeric indices if no pages were moved
3241          */
3242         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3243                 global $wgMaximumMovedPages;
3244                 // Check permissions
3245                 if( !$this->userCan( 'move-subpages' ) )
3246                         return array( 'cant-move-subpages' );
3247                 // Do the source and target namespaces support subpages?
3248                 if( !MWNamespace::hasSubpages( $this->getNamespace() ) )
3249                         return array( 'namespace-nosubpages',
3250                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3251                 if( !MWNamespace::hasSubpages( $nt->getNamespace() ) )
3252                         return array( 'namespace-nosubpages',
3253                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3254
3255                 $subpages = $this->getSubpages($wgMaximumMovedPages + 1);
3256                 $retval = array();
3257                 $count = 0;
3258                 foreach( $subpages as $oldSubpage ) {
3259                         $count++;
3260                         if( $count > $wgMaximumMovedPages ) {
3261                                 $retval[$oldSubpage->getPrefixedTitle()] =
3262                                                 array( 'movepage-max-pages',
3263                                                         $wgMaximumMovedPages );
3264                                 break;
3265                         }
3266
3267                         // We don't know whether this function was called before
3268                         // or after moving the root page, so check both
3269                         // $this and $nt
3270                         if( $oldSubpage->getArticleId() == $this->getArticleId() ||
3271                                         $oldSubpage->getArticleID() == $nt->getArticleId() )
3272                                 // When moving a page to a subpage of itself,
3273                                 // don't move it twice
3274                                 continue;
3275                         $newPageName = preg_replace(
3276                                         '#^'.preg_quote( $this->getDBkey(), '#' ).'#',
3277                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3278                                         $oldSubpage->getDBkey() );
3279                         if( $oldSubpage->isTalkPage() ) {
3280                                 $newNs = $nt->getTalkPage()->getNamespace();
3281                         } else {
3282                                 $newNs = $nt->getSubjectPage()->getNamespace();
3283                         }
3284                         # Bug 14385: we need makeTitleSafe because the new page names may
3285                         # be longer than 255 characters.
3286                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3287
3288                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3289                         if( $success === true ) {
3290                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3291                         } else {
3292                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3293                         }
3294                 }
3295                 return $retval;
3296         }
3297
3298         /**
3299          * Checks if this page is just a one-rev redirect.
3300          * Adds lock, so don't use just for light purposes.
3301          *
3302          * @return \type{\bool}
3303          */
3304         public function isSingleRevRedirect() {
3305                 $dbw = wfGetDB( DB_MASTER );
3306                 # Is it a redirect?
3307                 $row = $dbw->selectRow( 'page',
3308                         array( 'page_is_redirect', 'page_latest', 'page_id' ),
3309                         $this->pageCond(),
3310                         __METHOD__,
3311                         array( 'FOR UPDATE' )
3312                 );
3313                 # Cache some fields we may want
3314                 $this->mArticleID = $row ? intval($row->page_id) : 0;
3315                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3316                 $this->mLatestID = $row ? intval($row->page_latest) : false;
3317                 if( !$this->mRedirect ) {
3318                         return false;
3319                 }
3320                 # Does the article have a history?
3321                 $row = $dbw->selectField( array( 'page', 'revision'),
3322                         'rev_id',
3323                         array( 'page_namespace' => $this->getNamespace(),
3324                                 'page_title' => $this->getDBkey(),
3325                                 'page_id=rev_page',
3326                                 'page_latest != rev_id'
3327                         ),
3328                         __METHOD__,
3329                         array( 'FOR UPDATE' )
3330                 );
3331                 # Return true if there was no history
3332                 return ($row === false);
3333         }
3334
3335         /**
3336          * Checks if $this can be moved to a given Title
3337          * - Selects for update, so don't call it unless you mean business
3338          *
3339          * @param $nt \type{Title} the new title to check
3340          * @return \type{\bool} TRUE or FALSE
3341          */
3342         public function isValidMoveTarget( $nt ) {
3343                 $dbw = wfGetDB( DB_MASTER );
3344                 # Is it an existsing file?
3345                 if( $nt->getNamespace() == NS_FILE ) {
3346                         $file = wfLocalFile( $nt );
3347                         if( $file->exists() ) {
3348                                 wfDebug( __METHOD__ . ": file exists\n" );
3349                                 return false;
3350                         }
3351                 }
3352                 # Is it a redirect with no history?
3353                 if( !$nt->isSingleRevRedirect() ) {
3354                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3355                         return false;
3356                 }
3357                 # Get the article text
3358                 $rev = Revision::newFromTitle( $nt );
3359                 $text = $rev->getText();
3360                 # Does the redirect point to the source?
3361                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3362                 $m = array();
3363                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
3364                         $redirTitle = Title::newFromText( $m[1] );
3365                         if( !is_object( $redirTitle ) ||
3366                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3367                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
3368                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3369                                 return false;
3370                         }
3371                 } else {
3372                         # Fail safe
3373                         wfDebug( __METHOD__ . ": failsafe\n" );
3374                         return false;
3375                 }
3376                 return true;
3377         }
3378
3379         /**
3380          * Can this title be added to a user's watchlist?
3381          *
3382          * @return \type{\bool} TRUE or FALSE
3383          */
3384         public function isWatchable() {
3385                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
3386         }
3387
3388         /**
3389          * Get categories to which this Title belongs and return an array of
3390          * categories' names.
3391          *
3392          * @return \type{\array} array an array of parents in the form:
3393          *      $parent => $currentarticle
3394          */
3395         public function getParentCategories() {
3396                 global $wgContLang;
3397
3398                 $titlekey = $this->getArticleId();
3399                 $dbr = wfGetDB( DB_SLAVE );
3400                 $categorylinks = $dbr->tableName( 'categorylinks' );
3401
3402                 # NEW SQL
3403                 $sql = "SELECT * FROM $categorylinks"
3404                      ." WHERE cl_from='$titlekey'"
3405                          ." AND cl_from <> '0'"
3406                          ." ORDER BY cl_sortkey";
3407
3408                 $res = $dbr->query( $sql );
3409
3410                 if( $dbr->numRows( $res ) > 0 ) {
3411                         foreach( $res as $row )
3412                                 //$data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
3413                                 $data[$wgContLang->getNSText( NS_CATEGORY ).':'.$row->cl_to] = $this->getFullText();
3414                         $dbr->freeResult( $res );
3415                 } else {
3416                         $data = array();
3417                 }
3418                 return $data;
3419         }
3420
3421         /**
3422          * Get a tree of parent categories
3423          *
3424          * @param $children \type{\array} an array with the children in the keys, to check for circular refs
3425          * @return \type{\array} Tree of parent categories
3426          */
3427         public function getParentCategoryTree( $children = array() ) {
3428                 $stack = array();
3429                 $parents = $this->getParentCategories();
3430
3431                 if( $parents ) {
3432                         foreach( $parents as $parent => $current ) {
3433                                 if ( array_key_exists( $parent, $children ) ) {
3434                                         # Circular reference
3435                                         $stack[$parent] = array();
3436                                 } else {
3437                                         $nt = Title::newFromText($parent);
3438                                         if ( $nt ) {
3439                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array($parent => 1) );
3440                                         }
3441                                 }
3442                         }
3443                         return $stack;
3444                 } else {
3445                         return array();
3446                 }
3447         }
3448
3449
3450         /**
3451          * Get an associative array for selecting this title from
3452          * the "page" table
3453          *
3454          * @return \type{\array} Selection array
3455          */
3456         public function pageCond() {
3457                 if( $this->mArticleID > 0 ) {
3458                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
3459                         return array( 'page_id' => $this->mArticleID );
3460                 } else {
3461                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
3462                 }
3463         }
3464
3465         /**
3466          * Get the revision ID of the previous revision
3467          *
3468          * @param $revId \type{\int} Revision ID. Get the revision that was before this one.
3469          * @param $flags \type{\int} GAID_FOR_UPDATE
3470          * @return \twotypes{\int,\bool} Old revision ID, or FALSE if none exists
3471          */
3472         public function getPreviousRevisionID( $revId, $flags=0 ) {
3473                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3474                 return $db->selectField( 'revision', 'rev_id',
3475                         array(
3476                                 'rev_page' => $this->getArticleId($flags),
3477                                 'rev_id < ' . intval( $revId )
3478                         ),
3479                         __METHOD__,
3480                         array( 'ORDER BY' => 'rev_id DESC' )
3481                 );
3482         }
3483
3484         /**
3485          * Get the revision ID of the next revision
3486          *
3487          * @param $revId \type{\int} Revision ID. Get the revision that was after this one.
3488          * @param $flags \type{\int} GAID_FOR_UPDATE
3489          * @return \twotypes{\int,\bool} Next revision ID, or FALSE if none exists
3490          */
3491         public function getNextRevisionID( $revId, $flags=0 ) {
3492                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3493                 return $db->selectField( 'revision', 'rev_id',
3494                         array(
3495                                 'rev_page' => $this->getArticleId($flags),
3496                                 'rev_id > ' . intval( $revId )
3497                         ),
3498                         __METHOD__,
3499                         array( 'ORDER BY' => 'rev_id' )
3500                 );
3501         }
3502
3503         /**
3504          * Get the first revision of the page
3505          *
3506          * @param $flags \type{\int} GAID_FOR_UPDATE
3507          * @return Revision (or NULL if page doesn't exist)
3508          */
3509         public function getFirstRevision( $flags=0 ) {
3510                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3511                 $pageId = $this->getArticleId($flags);
3512                 if( !$pageId ) return null;
3513                 $row = $db->selectRow( 'revision', '*',
3514                         array( 'rev_page' => $pageId ),
3515                         __METHOD__,
3516                         array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
3517                 );
3518                 if( !$row ) {
3519                         return null;
3520                 } else {
3521                         return new Revision( $row );
3522                 }
3523         }
3524
3525         /**
3526          * Check if this is a new page
3527          *
3528          * @return bool
3529          */
3530         public function isNewPage() {
3531                 $dbr = wfGetDB( DB_SLAVE );
3532                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
3533         }
3534
3535         /**
3536          * Get the oldest revision timestamp of this page
3537          *
3538          * @return String: MW timestamp
3539          */
3540         public function getEarliestRevTime() {
3541                 $dbr = wfGetDB( DB_SLAVE );
3542                 if( $this->exists() ) {
3543                         $min = $dbr->selectField( 'revision',
3544                                 'MIN(rev_timestamp)',
3545                                 array( 'rev_page' => $this->getArticleId() ),
3546                                 __METHOD__ );
3547                         return wfTimestampOrNull( TS_MW, $min );
3548                 }
3549                 return null;
3550         }
3551
3552         /**
3553          * Get the number of revisions between the given revision IDs.
3554          * Used for diffs and other things that really need it.
3555          *
3556          * @param $old \type{\int} Revision ID.
3557          * @param $new \type{\int} Revision ID.
3558          * @return \type{\int} Number of revisions between these IDs.
3559          */
3560         public function countRevisionsBetween( $old, $new ) {
3561                 $dbr = wfGetDB( DB_SLAVE );
3562                 return (int)$dbr->selectField( 'revision', 'count(*)',
3563                         'rev_page = ' . intval( $this->getArticleId() ) .
3564                         ' AND rev_id > ' . intval( $old ) .
3565                         ' AND rev_id < ' . intval( $new ),
3566                         __METHOD__
3567                 );
3568         }
3569
3570         /**
3571          * Compare with another title.
3572          *
3573          * @param $title \type{Title}
3574          * @return \type{\bool} TRUE or FALSE
3575          */
3576         public function equals( Title $title ) {
3577                 // Note: === is necessary for proper matching of number-like titles.
3578                 return $this->getInterwiki() === $title->getInterwiki()
3579                         && $this->getNamespace() == $title->getNamespace()
3580                         && $this->getDBkey() === $title->getDBkey();
3581         }
3582
3583         /**
3584          * Callback for usort() to do title sorts by (namespace, title)
3585          *
3586          * @return Integer: result of string comparison, or namespace comparison
3587          */
3588         public static function compare( $a, $b ) {
3589                 if( $a->getNamespace() == $b->getNamespace() ) {
3590                         return strcmp( $a->getText(), $b->getText() );
3591                 } else {
3592                         return $a->getNamespace() - $b->getNamespace();
3593                 }
3594         }
3595
3596         /**
3597          * Return a string representation of this title
3598          *
3599          * @return \type{\string} String representation of this title
3600          */
3601         public function __toString() {
3602                 return $this->getPrefixedText();
3603         }
3604
3605         /**
3606          * Check if page exists.  For historical reasons, this function simply
3607          * checks for the existence of the title in the page table, and will
3608          * thus return false for interwiki links, special pages and the like.
3609          * If you want to know if a title can be meaningfully viewed, you should
3610          * probably call the isKnown() method instead.
3611          *
3612          * @return \type{\bool}
3613          */
3614         public function exists() {
3615                 return $this->getArticleId() != 0;
3616         }
3617
3618         /**
3619          * Should links to this title be shown as potentially viewable (i.e. as
3620          * "bluelinks"), even if there's no record by this title in the page
3621          * table?
3622          *
3623          * This function is semi-deprecated for public use, as well as somewhat
3624          * misleadingly named.  You probably just want to call isKnown(), which
3625          * calls this function internally.
3626          *
3627          * (ISSUE: Most of these checks are cheap, but the file existence check
3628          * can potentially be quite expensive.  Including it here fixes a lot of
3629          * existing code, but we might want to add an optional parameter to skip
3630          * it and any other expensive checks.)
3631          *
3632          * @return \type{\bool}
3633          */
3634         public function isAlwaysKnown() {
3635                 if( $this->mInterwiki != '' ) {
3636                         return true;  // any interwiki link might be viewable, for all we know
3637                 }
3638                 switch( $this->mNamespace ) {
3639                 case NS_MEDIA:
3640                 case NS_FILE:
3641                         return wfFindFile( $this );  // file exists, possibly in a foreign repo
3642                 case NS_SPECIAL:
3643                         return SpecialPage::exists( $this->getDBkey() );  // valid special page
3644                 case NS_MAIN:
3645                         return $this->mDbkeyform == '';  // selflink, possibly with fragment
3646                 case NS_MEDIAWIKI:
3647                         // If the page is form Mediawiki:message/lang, calling wfMsgWeirdKey causes
3648                         // the full l10n of that language to be loaded. That takes much memory and
3649                         // isn't needed. So we strip the language part away.
3650                         list( $basename, /* rest */ ) = explode( '/', $this->mDbkeyform, 2 );
3651                         return (bool)wfMsgWeirdKey( $basename );  // known system message
3652                 default:
3653                         return false;
3654                 }
3655         }
3656
3657         /**
3658          * Does this title refer to a page that can (or might) be meaningfully
3659          * viewed?  In particular, this function may be used to determine if
3660          * links to the title should be rendered as "bluelinks" (as opposed to
3661          * "redlinks" to non-existent pages).
3662          *
3663          * @return \type{\bool}
3664          */
3665         public function isKnown() {
3666                 return $this->exists() || $this->isAlwaysKnown();
3667         }
3668
3669         /**
3670          * Does this page have source text?
3671          *
3672          * @return Boolean
3673          */
3674         public function hasSourceText() {
3675                 if ( $this->exists() )
3676                         return true;
3677
3678                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
3679                         // If the page doesn't exist but is a known system message, default
3680                         // message content will be displayed, same for language subpages
3681                         // Also, if the page is form Mediawiki:message/lang, calling wfMsgWeirdKey
3682                         // causes the full l10n of that language to be loaded. That takes much
3683                         // memory and isn't needed. So we strip the language part away.
3684                         list( $basename, /* rest */ ) = explode( '/', $this->mDbkeyform, 2 );
3685                         return (bool)wfMsgWeirdKey( $basename );
3686                 }
3687
3688                 return false;
3689         }
3690
3691         /**
3692         * Is this in a namespace that allows actual pages?
3693         *
3694         * @return \type{\bool}
3695         * @internal note -- uses hardcoded namespace index instead of constants
3696         */
3697         public function canExist() {
3698                 return $this->mNamespace >=0 && $this->mNamespace != NS_MEDIA;
3699         }
3700
3701         /**
3702          * Update page_touched timestamps and send squid purge messages for
3703          * pages linking to this title. May be sent to the job queue depending
3704          * on the number of links. Typically called on create and delete.
3705          */
3706         public function touchLinks() {
3707                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
3708                 $u->doUpdate();
3709
3710                 if ( $this->getNamespace() == NS_CATEGORY ) {
3711                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
3712                         $u->doUpdate();
3713                 }
3714         }
3715
3716         /**
3717          * Get the last touched timestamp
3718          *
3719          * @param $db DatabaseBase: optional db
3720          * @return \type{\string} Last touched timestamp
3721          */
3722         public function getTouched( $db = null ) {
3723                 $db = isset($db) ? $db : wfGetDB( DB_SLAVE );
3724                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
3725                 return $touched;
3726         }
3727
3728         /**
3729          * Get the timestamp when this page was updated since the user last saw it.
3730          *
3731          * @param $user User
3732          * @return Mixed: string/null
3733          */
3734         public function getNotificationTimestamp( $user = null ) {
3735                 global $wgUser, $wgShowUpdatedMarker;
3736                 // Assume current user if none given
3737                 if( !$user ) $user = $wgUser;
3738                 // Check cache first
3739                 $uid = $user->getId();
3740                 if( isset($this->mNotificationTimestamp[$uid]) ) {
3741                         return $this->mNotificationTimestamp[$uid];
3742                 }
3743                 if( !$uid || !$wgShowUpdatedMarker ) {
3744                         return $this->mNotificationTimestamp[$uid] = false;
3745                 }
3746                 // Don't cache too much!
3747                 if( count($this->mNotificationTimestamp) >= self::CACHE_MAX ) {
3748                         $this->mNotificationTimestamp = array();
3749                 }
3750                 $dbr = wfGetDB( DB_SLAVE );
3751                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
3752                         'wl_notificationtimestamp',
3753                         array( 'wl_namespace' => $this->getNamespace(),
3754                                 'wl_title' => $this->getDBkey(),
3755                                 'wl_user' => $user->getId()
3756                         ),
3757                         __METHOD__
3758                 );
3759                 return $this->mNotificationTimestamp[$uid];
3760         }
3761
3762         /**
3763          * Get the trackback URL for this page
3764          *
3765          * @return \type{\string} Trackback URL
3766          */
3767         public function trackbackURL() {
3768                 global $wgScriptPath, $wgServer, $wgScriptExtension;
3769
3770                 return "$wgServer$wgScriptPath/trackback$wgScriptExtension?article="
3771                         . htmlspecialchars(urlencode($this->getPrefixedDBkey()));
3772         }
3773
3774         /**
3775          * Get the trackback RDF for this page
3776          *
3777          * @return \type{\string} Trackback RDF
3778          */
3779         public function trackbackRDF() {
3780                 $url = htmlspecialchars($this->getFullURL());
3781                 $title = htmlspecialchars($this->getText());
3782                 $tburl = $this->trackbackURL();
3783
3784                 // Autodiscovery RDF is placed in comments so HTML validator
3785                 // won't barf. This is a rather icky workaround, but seems
3786                 // frequently used by this kind of RDF thingy.
3787                 //
3788                 // Spec: http://www.sixapart.com/pronet/docs/trackback_spec
3789                 return "<!--
3790 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
3791          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
3792          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
3793 <rdf:Description
3794    rdf:about=\"$url\"
3795    dc:identifier=\"$url\"
3796    dc:title=\"$title\"
3797    trackback:ping=\"$tburl\" />
3798 </rdf:RDF>
3799 -->";
3800         }
3801
3802         /**
3803          * Generate strings used for xml 'id' names in monobook tabs
3804          *
3805          * @param $prepend string defaults to 'nstab-'
3806          * @return \type{\string} XML 'id' name
3807          */
3808         public function getNamespaceKey( $prepend = 'nstab-' ) {
3809                 global $wgContLang;
3810                 // Gets the subject namespace if this title
3811                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
3812                 // Checks if cononical namespace name exists for namespace
3813                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
3814                         // Uses canonical namespace name
3815                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
3816                 } else {
3817                         // Uses text of namespace
3818                         $namespaceKey = $this->getSubjectNsText();
3819                 }
3820                 // Makes namespace key lowercase
3821                 $namespaceKey = $wgContLang->lc( $namespaceKey );
3822                 // Uses main
3823                 if ( $namespaceKey == '' ) {
3824                         $namespaceKey = 'main';
3825                 }
3826                 // Changes file to image for backwards compatibility
3827                 if ( $namespaceKey == 'file' ) {
3828                         $namespaceKey = 'image';
3829                 }
3830                 return $prepend . $namespaceKey;
3831         }
3832
3833         /**
3834          * Returns true if this is a special page.
3835          *
3836          * @return boolean
3837          */
3838         public function isSpecialPage( ) {
3839                 return $this->getNamespace() == NS_SPECIAL;
3840         }
3841
3842         /**
3843          * Returns true if this title resolves to the named special page
3844          *
3845          * @param $name \type{\string} The special page name
3846          * @return boolean
3847          */
3848         public function isSpecial( $name ) {
3849                 if ( $this->getNamespace() == NS_SPECIAL ) {
3850                         list( $thisName, /* $subpage */ ) = SpecialPage::resolveAliasWithSubpage( $this->getDBkey() );
3851                         if ( $name == $thisName ) {
3852                                 return true;
3853                         }
3854                 }
3855                 return false;
3856         }
3857
3858         /**
3859          * If the Title refers to a special page alias which is not the local default,
3860          *
3861          * @return \type{Title} A new Title which points to the local default.
3862          *         Otherwise, returns $this.
3863          */
3864         public function fixSpecialName() {
3865                 if ( $this->getNamespace() == NS_SPECIAL ) {
3866                         $canonicalName = SpecialPage::resolveAlias( $this->mDbkeyform );
3867                         if ( $canonicalName ) {
3868                                 $localName = SpecialPage::getLocalNameFor( $canonicalName );
3869                                 if ( $localName != $this->mDbkeyform ) {
3870                                         return Title::makeTitle( NS_SPECIAL, $localName );
3871                                 }
3872                         }
3873                 }
3874                 return $this;
3875         }
3876
3877         /**
3878          * Is this Title in a namespace which contains content?
3879          * In other words, is this a content page, for the purposes of calculating
3880          * statistics, etc?
3881          *
3882          * @return \type{\bool}
3883          */
3884         public function isContentPage() {
3885                 return MWNamespace::isContent( $this->getNamespace() );
3886         }
3887
3888         /**
3889          * Get all extant redirects to this Title
3890          *
3891          * @param $ns \twotypes{\int,\null} Single namespace to consider;
3892          *            NULL to consider all namespaces
3893          * @return \type{\arrayof{Title}} Redirects to this title
3894          */
3895         public function getRedirectsHere( $ns = null ) {
3896                 $redirs = array();
3897
3898                 $dbr = wfGetDB( DB_SLAVE );
3899                 $where = array(
3900                         'rd_namespace' => $this->getNamespace(),
3901                         'rd_title' => $this->getDBkey(),
3902                         'rd_from = page_id'
3903                 );
3904                 if ( !is_null($ns) ) $where['page_namespace'] = $ns;
3905
3906                 $res = $dbr->select(
3907                         array( 'redirect', 'page' ),
3908                         array( 'page_namespace', 'page_title' ),
3909                         $where,
3910                         __METHOD__
3911                 );
3912
3913
3914                 foreach( $res as $row ) {
3915                         $redirs[] = self::newFromRow( $row );
3916                 }
3917                 return $redirs;
3918         }
3919
3920         /**
3921          * Check if this Title is a valid redirect target
3922          *
3923          * @return \type{\bool}
3924          */
3925         public function isValidRedirectTarget() {
3926                 global $wgInvalidRedirectTargets;
3927
3928                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
3929                 if( $this->isSpecial( 'Userlogout' ) ) {
3930                         return false;
3931                 }
3932
3933                 foreach( $wgInvalidRedirectTargets as $target ) {
3934                         if( $this->isSpecial( $target ) ) {
3935                                 return false;
3936                         }
3937                 }
3938
3939                 return true;
3940         }
3941
3942         /**
3943          * Get a backlink cache object
3944          *
3945          * @return object BacklinkCache
3946          */
3947         function getBacklinkCache() {
3948                 if ( is_null( $this->mBacklinkCache ) ) {
3949                         $this->mBacklinkCache = new BacklinkCache( $this );
3950                 }
3951                 return $this->mBacklinkCache;
3952         }
3953
3954         /**
3955          * Whether the magic words __INDEX__ and __NOINDEX__ function for
3956          * this page.
3957          *
3958          * @return Boolean
3959          */
3960         public function canUseNoindex(){
3961                 global $wgArticleRobotPolicies, $wgContentNamespaces,
3962                        $wgExemptFromUserRobotsControl;
3963
3964                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
3965                         ? $wgContentNamespaces
3966                         : $wgExemptFromUserRobotsControl;
3967
3968                 return !in_array( $this->mNamespace, $bannedNamespaces );
3969
3970         }
3971
3972         /**
3973          * Returns restriction types for the current Title
3974          *
3975          * @return array applicable restriction types
3976          */
3977         public function getRestrictionTypes() {
3978                 global $wgRestrictionTypes;
3979                 $types = $this->exists() ? $wgRestrictionTypes : array('create');
3980
3981                 if ( $this->getNamespace() == NS_FILE ) {
3982                         $types[] = 'upload';
3983                 }
3984
3985                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
3986
3987                 return $types;
3988         }
3989 }