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