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 = $this->getTitleProtection();
1438                         if( is_array($title_protection) ) {
1439                                 extract($title_protection); // is this extract() really needed?
1440
1441                                 if( $pt_create_perm == 'sysop' ) {
1442                                         $pt_create_perm = 'protect'; // B/C
1443                                 }
1444                                 if( $pt_create_perm == '' || !$user->isAllowed($pt_create_perm) ) {
1445                                         $errors[] = array( 'titleprotected', User::whoIs($pt_user), $pt_reason );
1446                                 }
1447                         }
1448                 } elseif( $action == 'move' ) {
1449                         // Check for immobile pages
1450                         if( !MWNamespace::isMovable( $this->getNamespace() ) ) {
1451                                 // Specific message for this case
1452                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1453                         } elseif( !$this->isMovable() ) {
1454                                 // Less specific message for rarer cases
1455                                 $errors[] = array( 'immobile-page' );
1456                         }
1457                 } elseif( $action == 'move-target' ) {
1458                         if( !MWNamespace::isMovable( $this->getNamespace() ) ) {
1459                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1460                         } elseif( !$this->isMovable() ) {
1461                                 $errors[] = array( 'immobile-target-page' );
1462                         }
1463                 }
1464
1465                 wfProfileOut( __METHOD__ );
1466                 return $errors;
1467         }
1468
1469         /**
1470          * Is this title subject to title protection?
1471          *
1472          * @return \type{\mixed} An associative array representing any existent title
1473          *   protection, or false if there's none.
1474          */
1475         private function getTitleProtection() {
1476                 // Can't protect pages in special namespaces
1477                 if ( $this->getNamespace() < 0 ) {
1478                         return false;
1479                 }
1480
1481                 // Can't protect pages that exist.
1482                 if ($this->exists()) {
1483                         return false;
1484                 }
1485
1486                 $dbr = wfGetDB( DB_SLAVE );
1487                 $res = $dbr->select( 'protected_titles', '*',
1488                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
1489                         __METHOD__ );
1490
1491                 if ($row = $dbr->fetchRow( $res )) {
1492                         return $row;
1493                 } else {
1494                         return false;
1495                 }
1496         }
1497
1498         /**
1499          * Update the title protection status
1500          *
1501          * @param $create_perm \type{\string} Permission required for creation
1502          * @param $reason \type{\string} Reason for protection
1503          * @param $expiry \type{\string} Expiry timestamp
1504          * @return boolean true
1505          */
1506         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
1507                 global $wgUser,$wgContLang;
1508
1509                 if ($create_perm == implode(',',$this->getRestrictions('create'))
1510                         && $expiry == $this->mRestrictionsExpiry['create']) {
1511                         // No change
1512                         return true;
1513                 }
1514
1515                 list ($namespace, $title) = array( $this->getNamespace(), $this->getDBkey() );
1516
1517                 $dbw = wfGetDB( DB_MASTER );
1518
1519                 $encodedExpiry = Block::encodeExpiry($expiry, $dbw );
1520
1521                 $expiry_description = '';
1522                 if ( $encodedExpiry != 'infinity' ) {
1523                         $expiry_description = ' (' . wfMsgForContent( 'protect-expiring',$wgContLang->timeanddate( $expiry ),
1524                                 $wgContLang->date( $expiry ) , $wgContLang->time( $expiry ) ).')';
1525                 }
1526                 else {
1527                         $expiry_description .= ' (' . wfMsgForContent( 'protect-expiry-indefinite' ).')';
1528                 }
1529
1530                 # Update protection table
1531                 if ($create_perm != '' ) {
1532                         $dbw->replace( 'protected_titles', array(array('pt_namespace', 'pt_title')),
1533                                 array(
1534                                         'pt_namespace' => $namespace,
1535                                         'pt_title' => $title,
1536                                         'pt_create_perm' => $create_perm,
1537                                         'pt_timestamp' => Block::encodeExpiry(wfTimestampNow(), $dbw),
1538                                         'pt_expiry' => $encodedExpiry,
1539                                         'pt_user' => $wgUser->getId(),
1540                                         'pt_reason' => $reason,
1541                                 ), __METHOD__
1542                         );
1543                 } else {
1544                         $dbw->delete( 'protected_titles', array( 'pt_namespace' => $namespace,
1545                                 'pt_title' => $title ), __METHOD__ );
1546                 }
1547                 # Update the protection log
1548                 if( $dbw->affectedRows() ) {
1549                         $log = new LogPage( 'protect' );
1550
1551                         if( $create_perm ) {
1552                                 $params = array("[create=$create_perm] $expiry_description",'');
1553                                 $log->addEntry( ( isset( $this->mRestrictions['create'] ) && $this->mRestrictions['create'] ) ? 'modify' : 'protect', $this, trim( $reason ), $params );
1554                         } else {
1555                                 $log->addEntry( 'unprotect', $this, $reason );
1556                         }
1557                 }
1558
1559                 return true;
1560         }
1561
1562         /**
1563          * Remove any title protection due to page existing
1564          */
1565         public function deleteTitleProtection() {
1566                 $dbw = wfGetDB( DB_MASTER );
1567
1568                 $dbw->delete( 'protected_titles',
1569                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
1570                         __METHOD__ );
1571         }
1572
1573         /**
1574          * Would anybody with sufficient privileges be able to move this page?
1575          * Some pages just aren't movable.
1576          *
1577          * @return \type{\bool} TRUE or FALSE
1578          */
1579         public function isMovable() {
1580                 return MWNamespace::isMovable( $this->getNamespace() ) && $this->getInterwiki() == '';
1581         }
1582
1583         /**
1584          * Can $wgUser read this page?
1585          *
1586          * @return \type{\bool}
1587          * @todo fold these checks into userCan()
1588          */
1589         public function userCanRead() {
1590                 global $wgUser, $wgGroupPermissions;
1591
1592                 static $useShortcut = null;
1593
1594                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
1595                 if( is_null( $useShortcut ) ) {
1596                         global $wgRevokePermissions;
1597                         $useShortcut = true;
1598                         if( empty( $wgGroupPermissions['*']['read'] ) ) {
1599                                 # Not a public wiki, so no shortcut
1600                                 $useShortcut = false;
1601                         } elseif( !empty( $wgRevokePermissions ) ) {
1602                                 /*
1603                                  * Iterate through each group with permissions being revoked (key not included since we don't care
1604                                  * what the group name is), then check if the read permission is being revoked. If it is, then
1605                                  * we don't use the shortcut below since the user might not be able to read, even though anon
1606                                  * reading is allowed.
1607                                  */
1608                                 foreach( $wgRevokePermissions as $perms ) {
1609                                         if( !empty( $perms['read'] ) ) {
1610                                                 # We might be removing the read right from the user, so no shortcut
1611                                                 $useShortcut = false;
1612                                                 break;
1613                                         }
1614                                 }
1615                         }
1616                 }
1617
1618                 $result = null;
1619                 wfRunHooks( 'userCan', array( &$this, &$wgUser, 'read', &$result ) );
1620                 if ( $result !== null ) {
1621                         return $result;
1622                 }
1623
1624                 # Shortcut for public wikis, allows skipping quite a bit of code
1625                 if ( $useShortcut )
1626                         return true;
1627
1628                 if( $wgUser->isAllowed( 'read' ) ) {
1629                         return true;
1630                 } else {
1631                         global $wgWhitelistRead;
1632
1633                         /**
1634                          * Always grant access to the login page.
1635                          * Even anons need to be able to log in.
1636                         */
1637                         if( $this->isSpecial( 'Userlogin' ) || $this->isSpecial( 'Resetpass' ) ) {
1638                                 return true;
1639                         }
1640
1641                         /**
1642                          * Bail out if there isn't whitelist
1643                          */
1644                         if( !is_array($wgWhitelistRead) ) {
1645                                 return false;
1646                         }
1647
1648                         /**
1649                          * Check for explicit whitelisting
1650                          */
1651                         $name = $this->getPrefixedText();
1652                         $dbName = $this->getPrefixedDBKey();
1653                         // Check with and without underscores
1654                         if( in_array($name,$wgWhitelistRead,true) || in_array($dbName,$wgWhitelistRead,true) )
1655                                 return true;
1656
1657                         /**
1658                          * Old settings might have the title prefixed with
1659                          * a colon for main-namespace pages
1660                          */
1661                         if( $this->getNamespace() == NS_MAIN ) {
1662                                 if( in_array( ':' . $name, $wgWhitelistRead ) )
1663                                         return true;
1664                         }
1665
1666                         /**
1667                          * If it's a special page, ditch the subpage bit
1668                          * and check again
1669                          */
1670                         if( $this->getNamespace() == NS_SPECIAL ) {
1671                                 $name = $this->getDBkey();
1672                                 list( $name, /* $subpage */) = SpecialPage::resolveAliasWithSubpage( $name );
1673                                 if ( $name === false ) {
1674                                         # Invalid special page, but we show standard login required message
1675                                         return false;
1676                                 }
1677
1678                                 $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
1679                                 if( in_array( $pure, $wgWhitelistRead, true ) )
1680                                         return true;
1681                         }
1682
1683                 }
1684                 return false;
1685         }
1686
1687         /**
1688          * Is this a talk page of some sort?
1689          *
1690          * @return \type{\bool}
1691          */
1692         public function isTalkPage() {
1693                 return MWNamespace::isTalk( $this->getNamespace() );
1694         }
1695
1696         /**
1697          * Is this a subpage?
1698          *
1699          * @return \type{\bool}
1700          */
1701         public function isSubpage() {
1702                 return MWNamespace::hasSubpages( $this->mNamespace )
1703                         ? strpos( $this->getText(), '/' ) !== false
1704                         : false;
1705         }
1706
1707         /**
1708          * Does this have subpages?  (Warning, usually requires an extra DB query.)
1709          *
1710          * @return \type{\bool}
1711          */
1712         public function hasSubpages() {
1713                 if( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1714                         # Duh
1715                         return false;
1716                 }
1717
1718                 # We dynamically add a member variable for the purpose of this method
1719                 # alone to cache the result.  There's no point in having it hanging
1720                 # around uninitialized in every Title object; therefore we only add it
1721                 # if needed and don't declare it statically.
1722                 if( isset( $this->mHasSubpages ) ) {
1723                         return $this->mHasSubpages;
1724                 }
1725
1726                 $subpages = $this->getSubpages( 1 );
1727                 if( $subpages instanceof TitleArray )
1728                         return $this->mHasSubpages = (bool)$subpages->count();
1729                 return $this->mHasSubpages = false;
1730         }
1731
1732         /**
1733          * Get all subpages of this page.
1734          *
1735          * @param $limit Maximum number of subpages to fetch; -1 for no limit
1736          * @return mixed TitleArray, or empty array if this page's namespace
1737          *  doesn't allow subpages
1738          */
1739         public function getSubpages( $limit = -1 ) {
1740                 if( !MWNamespace::hasSubpages( $this->getNamespace() ) )
1741                         return array();
1742
1743                 $dbr = wfGetDB( DB_SLAVE );
1744                 $conds['page_namespace'] = $this->getNamespace();
1745                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
1746                 $options = array();
1747                 if( $limit > -1 )
1748                         $options['LIMIT'] = $limit;
1749                 return $this->mSubpages = TitleArray::newFromResult(
1750                         $dbr->select( 'page',
1751                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
1752                                 $conds,
1753                                 __METHOD__,
1754                                 $options
1755                         )
1756                 );
1757         }
1758
1759         /**
1760          * Could this page contain custom CSS or JavaScript, based
1761          * on the title?
1762          *
1763          * @return \type{\bool}
1764          */
1765         public function isCssOrJsPage() {
1766                 return $this->mNamespace == NS_MEDIAWIKI
1767                         && preg_match( '!\.(?:css|js)$!u', $this->mTextform ) > 0;
1768         }
1769
1770         /**
1771          * Is this a .css or .js subpage of a user page?
1772          * @return \type{\bool}
1773          */
1774         public function isCssJsSubpage() {
1775                 return ( NS_USER == $this->mNamespace and preg_match("/\\/.*\\.(?:css|js)$/", $this->mTextform ) );
1776         }
1777
1778         /**
1779          * Is this a *valid* .css or .js subpage of a user page?
1780          * Check that the corresponding skin exists
1781          *
1782          * @return \type{\bool}
1783          */
1784         public function isValidCssJsSubpage() {
1785                 if ( $this->isCssJsSubpage() ) {
1786                         $name = $this->getSkinFromCssJsSubpage();
1787                         if ( $name == 'common' ) return true;
1788                         $skinNames = Skin::getSkinNames();
1789                         return array_key_exists( $name, $skinNames );
1790                 } else {
1791                         return false;
1792                 }
1793         }
1794
1795         /**
1796          * Trim down a .css or .js subpage title to get the corresponding skin name
1797          *
1798          * @return string containing skin name from .css or .js subpage title
1799          */
1800         public function getSkinFromCssJsSubpage() {
1801                 $subpage = explode( '/', $this->mTextform );
1802                 $subpage = $subpage[ count( $subpage ) - 1 ];
1803                 return( str_replace( array( '.css', '.js' ), array( '', '' ), $subpage ) );
1804         }
1805
1806         /**
1807          * Is this a .css subpage of a user page?
1808          *
1809          * @return \type{\bool}
1810          */
1811         public function isCssSubpage() {
1812                 return ( NS_USER == $this->mNamespace && preg_match("/\\/.*\\.css$/", $this->mTextform ) );
1813         }
1814
1815         /**
1816          * Is this a .js subpage of a user page?
1817          *
1818          * @return \type{\bool}
1819          */
1820         public function isJsSubpage() {
1821                 return ( NS_USER == $this->mNamespace && preg_match("/\\/.*\\.js$/", $this->mTextform ) );
1822         }
1823
1824         /**
1825          * Protect css subpages of user pages: can $wgUser edit
1826          * this page?
1827          *
1828          * @return \type{\bool}
1829          * @todo XXX: this might be better using restrictions
1830          */
1831         public function userCanEditCssSubpage() {
1832                 global $wgUser;
1833                 return ( ( $wgUser->isAllowed('editusercssjs') && $wgUser->isAllowed('editusercss') )
1834                         || preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1835         }
1836         /**
1837          * Protect js subpages of user pages: can $wgUser edit
1838          * this page?
1839          *
1840          * @return \type{\bool}
1841          * @todo XXX: this might be better using restrictions
1842          */
1843         public function userCanEditJsSubpage() {
1844                 global $wgUser;
1845                 return ( ( $wgUser->isAllowed('editusercssjs') && $wgUser->isAllowed('edituserjs') )
1846                        || preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1847         }
1848
1849         /**
1850          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
1851          *
1852          * @return \type{\bool} If the page is subject to cascading restrictions.
1853          */
1854         public function isCascadeProtected() {
1855                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
1856                 return ( $sources > 0 );
1857         }
1858
1859         /**
1860          * Cascading protection: Get the source of any cascading restrictions on this page.
1861          *
1862          * @param $get_pages \type{\bool} Whether or not to retrieve the actual pages
1863          *        that the restrictions have come from.
1864          * @return \type{\arrayof{mixed title array, restriction array}} Array of the Title
1865          *         objects of the pages from which cascading restrictions have come,
1866          *         false for none, or true if such restrictions exist, but $get_pages was not set.
1867          *         The restriction array is an array of each type, each of which contains a
1868          *         array of unique groups.
1869          */
1870         public function getCascadeProtectionSources( $get_pages = true ) {
1871                 $pagerestrictions = array();
1872
1873                 if ( isset( $this->mCascadeSources ) && $get_pages ) {
1874                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
1875                 } else if ( isset( $this->mHasCascadingRestrictions ) && !$get_pages ) {
1876                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
1877                 }
1878
1879                 wfProfileIn( __METHOD__ );
1880
1881                 $dbr = wfGetDB( DB_SLAVE );
1882
1883                 if ( $this->getNamespace() == NS_FILE ) {
1884                         $tables = array ('imagelinks', 'page_restrictions');
1885                         $where_clauses = array(
1886                                 'il_to' => $this->getDBkey(),
1887                                 'il_from=pr_page',
1888                                 'pr_cascade' => 1 );
1889                 } else {
1890                         $tables = array ('templatelinks', 'page_restrictions');
1891                         $where_clauses = array(
1892                                 'tl_namespace' => $this->getNamespace(),
1893                                 'tl_title' => $this->getDBkey(),
1894                                 'tl_from=pr_page',
1895                                 'pr_cascade' => 1 );
1896                 }
1897
1898                 if ( $get_pages ) {
1899                         $cols = array('pr_page', 'page_namespace', 'page_title', 'pr_expiry', 'pr_type', 'pr_level' );
1900                         $where_clauses[] = 'page_id=pr_page';
1901                         $tables[] = 'page';
1902                 } else {
1903                         $cols = array( 'pr_expiry' );
1904                 }
1905
1906                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
1907
1908                 $sources = $get_pages ? array() : false;
1909                 $now = wfTimestampNow();
1910                 $purgeExpired = false;
1911
1912                 foreach( $res as $row ) {
1913                         $expiry = Block::decodeExpiry( $row->pr_expiry );
1914                         if( $expiry > $now ) {
1915                                 if ($get_pages) {
1916                                         $page_id = $row->pr_page;
1917                                         $page_ns = $row->page_namespace;
1918                                         $page_title = $row->page_title;
1919                                         $sources[$page_id] = Title::makeTitle($page_ns, $page_title);
1920                                         # Add groups needed for each restriction type if its not already there
1921                                         # Make sure this restriction type still exists
1922
1923                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
1924                                                 $pagerestrictions[$row->pr_type] = array();
1925                                         }
1926
1927                                         if ( isset($pagerestrictions[$row->pr_type]) &&
1928                                                         !in_array($row->pr_level, $pagerestrictions[$row->pr_type]) ) {
1929                                                 $pagerestrictions[$row->pr_type][]=$row->pr_level;
1930                                         }
1931                                 } else {
1932                                         $sources = true;
1933                                 }
1934                         } else {
1935                                 // Trigger lazy purge of expired restrictions from the db
1936                                 $purgeExpired = true;
1937                         }
1938                 }
1939                 if( $purgeExpired ) {
1940                         Title::purgeExpiredRestrictions();
1941                 }
1942
1943                 wfProfileOut( __METHOD__ );
1944
1945                 if ( $get_pages ) {
1946                         $this->mCascadeSources = $sources;
1947                         $this->mCascadingRestrictions = $pagerestrictions;
1948                 } else {
1949                         $this->mHasCascadingRestrictions = $sources;
1950                 }
1951                 return array( $sources, $pagerestrictions );
1952         }
1953
1954         /**
1955          * Returns cascading restrictions for the current article
1956          *
1957          * @return Boolean
1958          */
1959         function areRestrictionsCascading() {
1960                 if (!$this->mRestrictionsLoaded) {
1961                         $this->loadRestrictions();
1962                 }
1963
1964                 return $this->mCascadeRestriction;
1965         }
1966
1967         /**
1968          * Loads a string into mRestrictions array
1969          *
1970          * @param $res \type{Resource} restrictions as an SQL result.
1971          * @param $oldFashionedRestrictions string comma-separated list of page
1972          *        restrictions from page table (pre 1.10)
1973          */
1974         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
1975                 $rows = array();
1976                 $dbr = wfGetDB( DB_SLAVE );
1977
1978                 while( $row = $dbr->fetchObject( $res ) ) {
1979                         $rows[] = $row;
1980                 }
1981
1982                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
1983         }
1984
1985         /**
1986          * Compiles list of active page restrictions from both page table (pre 1.10)
1987          * and page_restrictions table
1988          *
1989          * @param $rows array of db result objects
1990          * @param $oldFashionedRestrictions string comma-separated list of page
1991          *        restrictions from page table (pre 1.10)
1992          */
1993         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
1994                 $dbr = wfGetDB( DB_SLAVE );
1995
1996                 $restrictionTypes = $this->getRestrictionTypes();
1997
1998                 foreach( $restrictionTypes as $type ){
1999                         $this->mRestrictions[$type] = array();
2000                         $this->mRestrictionsExpiry[$type] = Block::decodeExpiry('');
2001                 }
2002
2003                 $this->mCascadeRestriction = false;
2004
2005                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2006
2007                 if ( $oldFashionedRestrictions === null ) {
2008                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2009                                 array( 'page_id' => $this->getArticleId() ), __METHOD__ );
2010                 }
2011
2012                 if ($oldFashionedRestrictions != '') {
2013
2014                         foreach( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2015                                 $temp = explode( '=', trim( $restrict ) );
2016                                 if(count($temp) == 1) {
2017                                         // old old format should be treated as edit/move restriction
2018                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2019                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2020                                 } else {
2021                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
2022                                 }
2023                         }
2024
2025                         $this->mOldRestrictions = true;
2026
2027                 }
2028
2029                 if( count($rows) ) {
2030                         # Current system - load second to make them override.
2031                         $now = wfTimestampNow();
2032                         $purgeExpired = false;
2033
2034                         foreach( $rows as $row ) {
2035                                 # Cycle through all the restrictions.
2036
2037                                 // Don't take care of restrictions types that aren't allowed
2038
2039                                 if( !in_array( $row->pr_type, $restrictionTypes ) )
2040                                         continue;
2041
2042                                 // This code should be refactored, now that it's being used more generally,
2043                                 // But I don't really see any harm in leaving it in Block for now -werdna
2044                                 $expiry = Block::decodeExpiry( $row->pr_expiry );
2045
2046                                 // Only apply the restrictions if they haven't expired!
2047                                 if ( !$expiry || $expiry > $now ) {
2048                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2049                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2050
2051                                         $this->mCascadeRestriction |= $row->pr_cascade;
2052                                 } else {
2053                                         // Trigger a lazy purge of expired restrictions
2054                                         $purgeExpired = true;
2055                                 }
2056                         }
2057
2058                         if( $purgeExpired ) {
2059                                 Title::purgeExpiredRestrictions();
2060                         }
2061                 }
2062
2063                 $this->mRestrictionsLoaded = true;
2064         }
2065
2066         /**
2067          * Load restrictions from the page_restrictions table
2068          *
2069          * @param $oldFashionedRestrictions string comma-separated list of page
2070          *        restrictions from page table (pre 1.10)
2071          */
2072         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2073                 if( !$this->mRestrictionsLoaded ) {
2074                         if ($this->exists()) {
2075                                 $dbr = wfGetDB( DB_SLAVE );
2076
2077                                 $res = $dbr->select( 'page_restrictions', '*',
2078                                         array ( 'pr_page' => $this->getArticleId() ), __METHOD__ );
2079
2080                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2081                         } else {
2082                                 $title_protection = $this->getTitleProtection();
2083
2084                                 if (is_array($title_protection)) {
2085                                         extract($title_protection);
2086
2087                                         $now = wfTimestampNow();
2088                                         $expiry = Block::decodeExpiry($pt_expiry);
2089
2090                                         if (!$expiry || $expiry > $now) {
2091                                                 // Apply the restrictions
2092                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2093                                                 $this->mRestrictions['create'] = explode(',', trim($pt_create_perm) );
2094                                         } else { // Get rid of the old restrictions
2095                                                 Title::purgeExpiredRestrictions();
2096                                         }
2097                                 } else {
2098                                         $this->mRestrictionsExpiry['create'] = Block::decodeExpiry('');
2099                                 }
2100                                 $this->mRestrictionsLoaded = true;
2101                         }
2102                 }
2103         }
2104
2105         /**
2106          * Purge expired restrictions from the page_restrictions table
2107          */
2108         static function purgeExpiredRestrictions() {
2109                 $dbw = wfGetDB( DB_MASTER );
2110                 $dbw->delete( 'page_restrictions',
2111                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2112                         __METHOD__ );
2113
2114                 $dbw->delete( 'protected_titles',
2115                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2116                         __METHOD__ );
2117         }
2118
2119         /**
2120          * Accessor/initialisation for mRestrictions
2121          *
2122          * @param $action \type{\string} action that permission needs to be checked for
2123          * @return \type{\arrayof{\string}} the array of groups allowed to edit this article
2124          */
2125         public function getRestrictions( $action ) {
2126                 if( !$this->mRestrictionsLoaded ) {
2127                         $this->loadRestrictions();
2128                 }
2129                 return isset( $this->mRestrictions[$action] )
2130                                 ? $this->mRestrictions[$action]
2131                                 : array();
2132         }
2133
2134         /**
2135          * Get the expiry time for the restriction against a given action
2136          *
2137          * @return 14-char timestamp, or 'infinity' if the page is protected forever
2138          *      or not protected at all, or false if the action is not recognised.
2139          */
2140         public function getRestrictionExpiry( $action ) {
2141                 if( !$this->mRestrictionsLoaded ) {
2142                         $this->loadRestrictions();
2143                 }
2144                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2145         }
2146
2147         /**
2148          * Is there a version of this page in the deletion archive?
2149          *
2150          * @return \type{\int} the number of archived revisions
2151          */
2152         public function isDeleted() {
2153                 if( $this->getNamespace() < 0 ) {
2154                         $n = 0;
2155                 } else {
2156                         $dbr = wfGetDB( DB_SLAVE );
2157                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2158                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2159                                 __METHOD__
2160                         );
2161                         if( $this->getNamespace() == NS_FILE ) {
2162                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2163                                         array( 'fa_name' => $this->getDBkey() ),
2164                                         __METHOD__
2165                                 );
2166                         }
2167                 }
2168                 return (int)$n;
2169         }
2170
2171         /**
2172          * Is there a version of this page in the deletion archive?
2173          *
2174          * @return Boolean
2175          */
2176         public function isDeletedQuick() {
2177                 if( $this->getNamespace() < 0 ) {
2178                         return false;
2179                 }
2180                 $dbr = wfGetDB( DB_SLAVE );
2181                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2182                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2183                         __METHOD__
2184                 );
2185                 if( !$deleted && $this->getNamespace() == NS_FILE ) {
2186                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2187                                 array( 'fa_name' => $this->getDBkey() ),
2188                                 __METHOD__
2189                         );
2190                 }
2191                 return $deleted;
2192         }
2193
2194         /**
2195          * Get the article ID for this Title from the link cache,
2196          * adding it if necessary
2197          *
2198          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select
2199          *  for update
2200          * @return \type{\int} the ID
2201          */
2202         public function getArticleID( $flags = 0 ) {
2203                 if( $this->getNamespace() < 0 ) {
2204                         return $this->mArticleID = 0;
2205                 }
2206                 $linkCache = LinkCache::singleton();
2207                 if( $flags & GAID_FOR_UPDATE ) {
2208                         $oldUpdate = $linkCache->forUpdate( true );
2209                         $linkCache->clearLink( $this );
2210                         $this->mArticleID = $linkCache->addLinkObj( $this );
2211                         $linkCache->forUpdate( $oldUpdate );
2212                 } else {
2213                         if( -1 == $this->mArticleID ) {
2214                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2215                         }
2216                 }
2217                 return $this->mArticleID;
2218         }
2219
2220         /**
2221          * Is this an article that is a redirect page?
2222          * Uses link cache, adding it if necessary
2223          *
2224          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select for update
2225          * @return \type{\bool}
2226          */
2227         public function isRedirect( $flags = 0 ) {
2228                 if( !is_null($this->mRedirect) )
2229                         return $this->mRedirect;
2230                 # Calling getArticleID() loads the field from cache as needed
2231                 if( !$this->getArticleID($flags) ) {
2232                         return $this->mRedirect = false;
2233                 }
2234                 $linkCache = LinkCache::singleton();
2235                 $this->mRedirect = (bool)$linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2236
2237                 return $this->mRedirect;
2238         }
2239
2240         /**
2241          * What is the length of this page?
2242          * Uses link cache, adding it if necessary
2243          *
2244          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select for update
2245          * @return \type{\bool}
2246          */
2247         public function getLength( $flags = 0 ) {
2248                 if( $this->mLength != -1 )
2249                         return $this->mLength;
2250                 # Calling getArticleID() loads the field from cache as needed
2251                 if( !$this->getArticleID($flags) ) {
2252                         return $this->mLength = 0;
2253                 }
2254                 $linkCache = LinkCache::singleton();
2255                 $this->mLength = intval( $linkCache->getGoodLinkFieldObj( $this, 'length' ) );
2256
2257                 return $this->mLength;
2258         }
2259
2260         /**
2261          * What is the page_latest field for this page?
2262          *
2263          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select for update
2264          * @return \type{\int} or false if the page doesn't exist
2265          */
2266         public function getLatestRevID( $flags = 0 ) {
2267                 if( $this->mLatestID !== false )
2268                         return $this->mLatestID;
2269
2270                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB(DB_MASTER) : wfGetDB(DB_SLAVE);
2271                 $this->mLatestID = (int)$db->selectField(
2272                         'page', 'page_latest', $this->pageCond(), __METHOD__ );
2273                 return $this->mLatestID;
2274         }
2275
2276         /**
2277          * This clears some fields in this object, and clears any associated
2278          * keys in the "bad links" section of the link cache.
2279          *
2280          * - This is called from Article::insertNewArticle() to allow
2281          * loading of the new page_id. It's also called from
2282          * Article::doDeleteArticle()
2283          *
2284          * @param $newid \type{\int} the new Article ID
2285          */
2286         public function resetArticleID( $newid ) {
2287                 $linkCache = LinkCache::singleton();
2288                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
2289
2290                 if ( $newid === false ) {
2291                         $this->mArticleID = -1;
2292                 } else {
2293                         $this->mArticleID = intval( $newid );
2294                 }
2295                 $this->mRestrictionsLoaded = false;
2296                 $this->mRestrictions = array();
2297                 $this->mRedirect = null;
2298                 $this->mLength = -1;
2299                 $this->mLatestID = false;
2300         }
2301
2302         /**
2303          * Updates page_touched for this page; called from LinksUpdate.php
2304          *
2305          * @return \type{\bool} true if the update succeded
2306          */
2307         public function invalidateCache() {
2308                 if( wfReadOnly() ) {
2309                         return;
2310                 }
2311                 $dbw = wfGetDB( DB_MASTER );
2312                 $success = $dbw->update( 'page',
2313                         array( 'page_touched' => $dbw->timestamp() ),
2314                         $this->pageCond(),
2315                         __METHOD__
2316                 );
2317                 HTMLFileCache::clearFileCache( $this );
2318                 return $success;
2319         }
2320
2321         /**
2322          * Prefix some arbitrary text with the namespace or interwiki prefix
2323          * of this object
2324          *
2325          * @param $name \type{\string} the text
2326          * @return \type{\string} the prefixed text
2327          * @private
2328          */
2329         /* private */ function prefix( $name ) {
2330                 $p = '';
2331                 if ( $this->mInterwiki != '' ) {
2332                         $p = $this->mInterwiki . ':';
2333                 }
2334                 if ( 0 != $this->mNamespace ) {
2335                         $p .= $this->getNsText() . ':';
2336                 }
2337                 return $p . $name;
2338         }
2339
2340         /**
2341          * Returns a simple regex that will match on characters and sequences invalid in titles.
2342          * Note that this doesn't pick up many things that could be wrong with titles, but that
2343          * replacing this regex with something valid will make many titles valid.
2344          *
2345          * @return string regex string
2346          */
2347         static function getTitleInvalidRegex() {
2348                 static $rxTc = false;
2349                 if( !$rxTc ) {
2350                         # Matching titles will be held as illegal.
2351                         $rxTc = '/' .
2352                                 # Any character not allowed is forbidden...
2353                                 '[^' . Title::legalChars() . ']' .
2354                                 # URL percent encoding sequences interfere with the ability
2355                                 # to round-trip titles -- you can't link to them consistently.
2356                                 '|%[0-9A-Fa-f]{2}' .
2357                                 # XML/HTML character references produce similar issues.
2358                                 '|&[A-Za-z0-9\x80-\xff]+;' .
2359                                 '|&#[0-9]+;' .
2360                                 '|&#x[0-9A-Fa-f]+;' .
2361                                 '/S';
2362                 }
2363
2364                 return $rxTc;
2365         }
2366
2367         /**
2368          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
2369          *
2370          * @param $text string containing title to capitalize
2371          * @param $ns int namespace index, defaults to NS_MAIN
2372          * @return String containing capitalized title
2373          */
2374         public static function capitalize( $text, $ns = NS_MAIN ) {
2375                 global $wgContLang;
2376
2377                 if ( MWNamespace::isCapitalized( $ns ) )
2378                         return $wgContLang->ucfirst( $text );
2379                 else
2380                         return $text;
2381         }
2382
2383         /**
2384          * Secure and split - main initialisation function for this object
2385          *
2386          * Assumes that mDbkeyform has been set, and is urldecoded
2387          * and uses underscores, but not otherwise munged.  This function
2388          * removes illegal characters, splits off the interwiki and
2389          * namespace prefixes, sets the other forms, and canonicalizes
2390          * everything.
2391          *
2392          * @return \type{\bool} true on success
2393          */
2394         private function secureAndSplit() {
2395                 global $wgContLang, $wgLocalInterwiki;
2396
2397                 # Initialisation
2398                 $rxTc = self::getTitleInvalidRegex();
2399
2400                 $this->mInterwiki = $this->mFragment = '';
2401                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2402
2403                 $dbkey = $this->mDbkeyform;
2404
2405                 # Strip Unicode bidi override characters.
2406                 # Sometimes they slip into cut-n-pasted page titles, where the
2407                 # override chars get included in list displays.
2408                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
2409
2410                 # Clean up whitespace
2411                 # Note: use of the /u option on preg_replace here will cause
2412                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
2413                 # conveniently disabling them.
2414                 #
2415                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
2416                 $dbkey = trim( $dbkey, '_' );
2417
2418                 if ( $dbkey == '' ) {
2419                         return false;
2420                 }
2421
2422                 if( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2423                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2424                         return false;
2425                 }
2426
2427                 $this->mDbkeyform = $dbkey;
2428
2429                 # Initial colon indicates main namespace rather than specified default
2430                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
2431                 if ( ':' == $dbkey{0} ) {
2432                         $this->mNamespace = NS_MAIN;
2433                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
2434                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
2435                 }
2436
2437                 # Namespace or interwiki prefix
2438                 $firstPass = true;
2439                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
2440                 do {
2441                         $m = array();
2442                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
2443                                 $p = $m[1];
2444                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
2445                                         # Ordinary namespace
2446                                         $dbkey = $m[2];
2447                                         $this->mNamespace = $ns;
2448                                         # For Talk:X pages, check if X has a "namespace" prefix
2449                                         if( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
2450                                                 if( $wgContLang->getNsIndex( $x[1] ) )
2451                                                         return false; # Disallow Talk:File:x type titles...
2452                                                 else if( Interwiki::isValidInterwiki( $x[1] ) )
2453                                                         return false; # Disallow Talk:Interwiki:x type titles...
2454                                         }
2455                                 } elseif( Interwiki::isValidInterwiki( $p ) ) {
2456                                         if( !$firstPass ) {
2457                                                 # Can't make a local interwiki link to an interwiki link.
2458                                                 # That's just crazy!
2459                                                 return false;
2460                                         }
2461
2462                                         # Interwiki link
2463                                         $dbkey = $m[2];
2464                                         $this->mInterwiki = $wgContLang->lc( $p );
2465
2466                                         # Redundant interwiki prefix to the local wiki
2467                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
2468                                                 if( $dbkey == '' ) {
2469                                                         # Can't have an empty self-link
2470                                                         return false;
2471                                                 }
2472                                                 $this->mInterwiki = '';
2473                                                 $firstPass = false;
2474                                                 # Do another namespace split...
2475                                                 continue;
2476                                         }
2477
2478                                         # If there's an initial colon after the interwiki, that also
2479                                         # resets the default namespace
2480                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
2481                                                 $this->mNamespace = NS_MAIN;
2482                                                 $dbkey = substr( $dbkey, 1 );
2483                                         }
2484                                 }
2485                                 # If there's no recognized interwiki or namespace,
2486                                 # then let the colon expression be part of the title.
2487                         }
2488                         break;
2489                 } while( true );
2490
2491                 # We already know that some pages won't be in the database!
2492                 #
2493                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
2494                         $this->mArticleID = 0;
2495                 }
2496                 $fragment = strstr( $dbkey, '#' );
2497                 if ( false !== $fragment ) {
2498                         $this->setFragment( $fragment );
2499                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
2500                         # remove whitespace again: prevents "Foo_bar_#"
2501                         # becoming "Foo_bar_"
2502                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
2503                 }
2504
2505                 # Reject illegal characters.
2506                 #
2507                 if( preg_match( $rxTc, $dbkey ) ) {
2508                         return false;
2509                 }
2510
2511                 /**
2512                  * Pages with "/./" or "/../" appearing in the URLs will often be un-
2513                  * reachable due to the way web browsers deal with 'relative' URLs.
2514                  * Also, they conflict with subpage syntax.  Forbid them explicitly.
2515                  */
2516                 if ( strpos( $dbkey, '.' ) !== false &&
2517                      ( $dbkey === '.' || $dbkey === '..' ||
2518                        strpos( $dbkey, './' ) === 0  ||
2519                        strpos( $dbkey, '../' ) === 0 ||
2520                        strpos( $dbkey, '/./' ) !== false ||
2521                        strpos( $dbkey, '/../' ) !== false  ||
2522                        substr( $dbkey, -2 ) == '/.' ||
2523                        substr( $dbkey, -3 ) == '/..' ) )
2524                 {
2525                         return false;
2526                 }
2527
2528                 /**
2529                  * Magic tilde sequences? Nu-uh!
2530                  */
2531                 if( strpos( $dbkey, '~~~' ) !== false ) {
2532                         return false;
2533                 }
2534
2535                 /**
2536                  * Limit the size of titles to 255 bytes.
2537                  * This is typically the size of the underlying database field.
2538                  * We make an exception for special pages, which don't need to be stored
2539                  * in the database, and may edge over 255 bytes due to subpage syntax
2540                  * for long titles, e.g. [[Special:Block/Long name]]
2541                  */
2542                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
2543                   strlen( $dbkey ) > 512 )
2544                 {
2545                         return false;
2546                 }
2547
2548                 /**
2549                  * Normally, all wiki links are forced to have
2550                  * an initial capital letter so [[foo]] and [[Foo]]
2551                  * point to the same place.
2552                  *
2553                  * Don't force it for interwikis, since the other
2554                  * site might be case-sensitive.
2555                  */
2556                 $this->mUserCaseDBKey = $dbkey;
2557                 if(  $this->mInterwiki == '') {
2558                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
2559                 }
2560
2561                 /**
2562                  * Can't make a link to a namespace alone...
2563                  * "empty" local links can only be self-links
2564                  * with a fragment identifier.
2565                  */
2566                 if( $dbkey == '' &&
2567                         $this->mInterwiki == '' &&
2568                         $this->mNamespace != NS_MAIN ) {
2569                         return false;
2570                 }
2571                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
2572                 // IP names are not allowed for accounts, and can only be referring to
2573                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
2574                 // there are numerous ways to present the same IP. Having sp:contribs scan
2575                 // them all is silly and having some show the edits and others not is
2576                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
2577                 $dbkey = ($this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK) ?
2578                         IP::sanitizeIP( $dbkey ) : $dbkey;
2579                 // Any remaining initial :s are illegal.
2580                 if ( $dbkey !== '' && ':' == $dbkey{0} ) {
2581                         return false;
2582                 }
2583
2584                 # Fill fields
2585                 $this->mDbkeyform = $dbkey;
2586                 $this->mUrlform = wfUrlencode( $dbkey );
2587
2588                 $this->mTextform = str_replace( '_', ' ', $dbkey );
2589
2590                 return true;
2591         }
2592
2593         /**
2594          * Set the fragment for this title. Removes the first character from the
2595          * specified fragment before setting, so it assumes you're passing it with
2596          * an initial "#".
2597          *
2598          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
2599          * Still in active use privately.
2600          *
2601          * @param $fragment \type{\string} text
2602          */
2603         public function setFragment( $fragment ) {
2604                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
2605         }
2606
2607         /**
2608          * Get a Title object associated with the talk page of this article
2609          *
2610          * @return \type{Title} the object for the talk page
2611          */
2612         public function getTalkPage() {
2613                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
2614         }
2615
2616         /**
2617          * Get a title object associated with the subject page of this
2618          * talk page
2619          *
2620          * @return \type{Title} the object for the subject page
2621          */
2622         public function getSubjectPage() {
2623                 // Is this the same title?
2624                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
2625                 if( $this->getNamespace() == $subjectNS ) {
2626                         return $this;
2627                 }
2628                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
2629         }
2630
2631         /**
2632          * Get an array of Title objects linking to this Title
2633          * Also stores the IDs in the link cache.
2634          *
2635          * WARNING: do not use this function on arbitrary user-supplied titles!
2636          * On heavily-used templates it will max out the memory.
2637          *
2638          * @param $options Array: may be FOR UPDATE
2639          * @param $table String: table name
2640          * @param $prefix String: fields prefix
2641          * @return \type{\arrayof{Title}} the Title objects linking here
2642          */
2643         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
2644                 $linkCache = LinkCache::singleton();
2645
2646                 if ( count( $options ) > 0 ) {
2647                         $db = wfGetDB( DB_MASTER );
2648                 } else {
2649                         $db = wfGetDB( DB_SLAVE );
2650                 }
2651
2652                 $res = $db->select( array( 'page', $table ),
2653                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect' ),
2654                         array(
2655                                 "{$prefix}_from=page_id",
2656                                 "{$prefix}_namespace" => $this->getNamespace(),
2657                                 "{$prefix}_title"     => $this->getDBkey() ),
2658                         __METHOD__,
2659                         $options );
2660
2661                 $retVal = array();
2662                 if ( $db->numRows( $res ) ) {
2663                         foreach( $res as $row ) {
2664                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
2665                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj, $row->page_len, $row->page_is_redirect );
2666                                         $retVal[] = $titleObj;
2667                                 }
2668                         }
2669                 }
2670                 $db->freeResult( $res );
2671                 return $retVal;
2672         }
2673
2674         /**
2675          * Get an array of Title objects using this Title as a template
2676          * Also stores the IDs in the link cache.
2677          *
2678          * WARNING: do not use this function on arbitrary user-supplied titles!
2679          * On heavily-used templates it will max out the memory.
2680          *
2681          * @param $options Array: may be FOR UPDATE
2682          * @return \type{\arrayof{Title}} the Title objects linking here
2683          */
2684         public function getTemplateLinksTo( $options = array() ) {
2685                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
2686         }
2687
2688         /**
2689          * Get an array of Title objects referring to non-existent articles linked from this page
2690          *
2691          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
2692          * @return \type{\arrayof{Title}} the Title objects
2693          */
2694         public function getBrokenLinksFrom() {
2695                 if ( $this->getArticleId() == 0 ) {
2696                         # All links from article ID 0 are false positives
2697                         return array();
2698                 }
2699
2700                 $dbr = wfGetDB( DB_SLAVE );
2701                 $res = $dbr->select(
2702                         array( 'page', 'pagelinks' ),
2703                         array( 'pl_namespace', 'pl_title' ),
2704                         array(
2705                                 'pl_from' => $this->getArticleId(),
2706                                 'page_namespace IS NULL'
2707                         ),
2708                         __METHOD__, array(),
2709                         array(
2710                                 'page' => array(
2711                                         'LEFT JOIN',
2712                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
2713                                 )
2714                         )
2715                 );
2716
2717                 $retVal = array();
2718                 foreach( $res as $row ) {
2719                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
2720                 }
2721                 return $retVal;
2722         }
2723
2724
2725         /**
2726          * Get a list of URLs to purge from the Squid cache when this
2727          * page changes
2728          *
2729          * @return \type{\arrayof{\string}} the URLs
2730          */
2731         public function getSquidURLs() {
2732                 global $wgContLang;
2733
2734                 $urls = array(
2735                         $this->getInternalURL(),
2736                         $this->getInternalURL( 'action=history' )
2737                 );
2738
2739                 // purge variant urls as well
2740                 if($wgContLang->hasVariants()){
2741                         $variants = $wgContLang->getVariants();
2742                         foreach($variants as $vCode){
2743                                 if($vCode==$wgContLang->getCode()) continue; // we don't want default variant
2744                                 $urls[] = $this->getInternalURL('',$vCode);
2745                         }
2746                 }
2747
2748                 return $urls;
2749         }
2750
2751         /**
2752          * Purge all applicable Squid URLs
2753          */
2754         public function purgeSquid() {
2755                 global $wgUseSquid;
2756                 if ( $wgUseSquid ) {
2757                         $urls = $this->getSquidURLs();
2758                         $u = new SquidUpdate( $urls );
2759                         $u->doUpdate();
2760                 }
2761         }
2762
2763         /**
2764          * Move this page without authentication
2765          *
2766          * @param $nt \type{Title} the new page Title
2767          * @return \type{\mixed} true on success, getUserPermissionsErrors()-like array on failure
2768          */
2769         public function moveNoAuth( &$nt ) {
2770                 return $this->moveTo( $nt, false );
2771         }
2772
2773         /**
2774          * Check whether a given move operation would be valid.
2775          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
2776          *
2777          * @param $nt \type{Title} the new title
2778          * @param $auth \type{\bool} indicates whether $wgUser's permissions
2779          *  should be checked
2780          * @param $reason \type{\string} is the log summary of the move, used for spam checking
2781          * @return \type{\mixed} True on success, getUserPermissionsErrors()-like array on failure
2782          */
2783         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
2784                 global $wgUser;
2785
2786                 $errors = array();
2787                 if( !$nt ) {
2788                         // Normally we'd add this to $errors, but we'll get
2789                         // lots of syntax errors if $nt is not an object
2790                         return array(array('badtitletext'));
2791                 }
2792                 if( $this->equals( $nt ) ) {
2793                         $errors[] = array('selfmove');
2794                 }
2795                 if( !$this->isMovable() ) {
2796                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
2797                 }
2798                 if ( $nt->getInterwiki() != '' ) {
2799                         $errors[] = array( 'immobile-target-namespace-iw' );
2800                 }
2801                 if ( !$nt->isMovable() ) {
2802                         $errors[] = array('immobile-target-namespace', $nt->getNsText() );
2803                 }
2804
2805                 $oldid = $this->getArticleID();
2806                 $newid = $nt->getArticleID();
2807
2808                 if ( strlen( $nt->getDBkey() ) < 1 ) {
2809                         $errors[] = array('articleexists');
2810                 }
2811                 if ( ( $this->getDBkey() == '' ) ||
2812                          ( !$oldid ) ||
2813                      ( $nt->getDBkey() == '' ) ) {
2814                         $errors[] = array('badarticleerror');
2815                 }
2816
2817                 // Image-specific checks
2818                 if( $this->getNamespace() == NS_FILE ) {
2819                         $file = wfLocalFile( $this );
2820                         if( $file->exists() ) {
2821                                 if( $nt->getNamespace() != NS_FILE ) {
2822                                         $errors[] = array('imagenocrossnamespace');
2823                                 }
2824                                 if( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
2825                                         $errors[] = array('imageinvalidfilename');
2826                                 }
2827                                 if( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
2828                                         $errors[] = array('imagetypemismatch');
2829                                 }
2830                         }
2831                         $destfile = wfLocalFile( $nt );
2832                         if( !$wgUser->isAllowed( 'reupload-shared' ) && !$destfile->exists() && wfFindFile( $nt ) ) {
2833                                 $errors[] = array( 'file-exists-sharedrepo' );
2834                         }
2835
2836                 }
2837
2838                 if ( $auth ) {
2839                         $errors = wfMergeErrorArrays( $errors,
2840                                 $this->getUserPermissionsErrors('move', $wgUser),
2841                                 $this->getUserPermissionsErrors('edit', $wgUser),
2842                                 $nt->getUserPermissionsErrors('move-target', $wgUser),
2843                                 $nt->getUserPermissionsErrors('edit', $wgUser) );
2844                 }
2845
2846                 $match = EditPage::matchSummarySpamRegex( $reason );
2847                 if( $match !== false ) {
2848                         // This is kind of lame, won't display nice
2849                         $errors[] = array('spamprotectiontext');
2850                 }
2851
2852                 $err = null;
2853                 if( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
2854                         $errors[] = array('hookaborted', $err);
2855                 }
2856
2857                 # The move is allowed only if (1) the target doesn't exist, or
2858                 # (2) the target is a redirect to the source, and has no history
2859                 # (so we can undo bad moves right after they're done).
2860
2861                 if ( 0 != $newid ) { # Target exists; check for validity
2862                         if ( ! $this->isValidMoveTarget( $nt ) ) {
2863                                 $errors[] = array('articleexists');
2864                         }
2865                 } else {
2866                         $tp = $nt->getTitleProtection();
2867                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
2868                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
2869                                 $errors[] = array('cantmove-titleprotected');
2870                         }
2871                 }
2872                 if(empty($errors))
2873                         return true;
2874                 return $errors;
2875         }
2876
2877         /**
2878          * Move a title to a new location
2879          *
2880          * @param $nt \type{Title} the new title
2881          * @param $auth \type{\bool} indicates whether $wgUser's permissions
2882          *  should be checked
2883          * @param $reason \type{\string} The reason for the move
2884          * @param $createRedirect \type{\bool} Whether to create a redirect from the old title to the new title.
2885          *  Ignored if the user doesn't have the suppressredirect right.
2886          * @return \type{\mixed} true on success, getUserPermissionsErrors()-like array on failure
2887          */
2888         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
2889                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
2890                 if( is_array( $err ) ) {
2891                         return $err;
2892                 }
2893
2894                 // If it is a file, move it first. It is done before all other moving stuff is done because it's hard to revert
2895                 $dbw = wfGetDB( DB_MASTER );
2896                 if( $this->getNamespace() == NS_FILE ) {
2897                         $file = wfLocalFile( $this );
2898                         if( $file->exists() ) {
2899                                 $status = $file->move( $nt );
2900                                 if( !$status->isOk() ) {
2901                                         return $status->getErrorsArray();
2902                                 }
2903                         }
2904                 }
2905
2906                 $pageid = $this->getArticleID();
2907                 $protected = $this->isProtected();
2908                 if( $nt->exists() ) {
2909                         $err = $this->moveOverExistingRedirect( $nt, $reason, $createRedirect );
2910                         $pageCountChange = ($createRedirect ? 0 : -1);
2911                 } else { # Target didn't exist, do normal move.
2912                         $err = $this->moveToNewTitle( $nt, $reason, $createRedirect );
2913                         $pageCountChange = ($createRedirect ? 1 : 0);
2914                 }
2915
2916                 if( is_array( $err ) ) {
2917                         return $err;
2918                 }
2919                 $redirid = $this->getArticleID();
2920
2921                 // Category memberships include a sort key which may be customized.
2922                 // If it's left as the default (the page title), we need to update
2923                 // the sort key to match the new title.
2924                 //
2925                 // Be careful to avoid resetting cl_timestamp, which may disturb
2926                 // time-based lists on some sites.
2927                 //
2928                 // Warning -- if the sort key is *explicitly* set to the old title,
2929                 // we can't actually distinguish it from a default here, and it'll
2930                 // be set to the new title even though it really shouldn't.
2931                 // It'll get corrected on the next edit, but resetting cl_timestamp.
2932                 $dbw->update( 'categorylinks',
2933                         array(
2934                                 'cl_sortkey' => $nt->getPrefixedText(),
2935                                 'cl_timestamp=cl_timestamp' ),
2936                         array(
2937                                 'cl_from' => $pageid,
2938                                 'cl_sortkey' => $this->getPrefixedText() ),
2939                         __METHOD__ );
2940
2941                 if( $protected ) {
2942                         # Protect the redirect title as the title used to be...
2943                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
2944                                 array(
2945                                         'pr_page'    => $redirid,
2946                                         'pr_type'    => 'pr_type',
2947                                         'pr_level'   => 'pr_level',
2948                                         'pr_cascade' => 'pr_cascade',
2949                                         'pr_user'    => 'pr_user',
2950                                         'pr_expiry'  => 'pr_expiry'
2951                                 ),
2952                                 array( 'pr_page' => $pageid ),
2953                                 __METHOD__,
2954                                 array( 'IGNORE' )
2955                         );
2956                         # Update the protection log
2957                         $log = new LogPage( 'protect' );
2958                         $comment = wfMsgForContent( 'prot_1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
2959                         if( $reason ) $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
2960                         $log->addEntry( 'move_prot', $nt, $comment, array($this->getPrefixedText()) ); // FIXME: $params?
2961                 }
2962
2963                 # Update watchlists
2964                 $oldnamespace = $this->getNamespace() & ~1;
2965                 $newnamespace = $nt->getNamespace() & ~1;
2966                 $oldtitle = $this->getDBkey();
2967                 $newtitle = $nt->getDBkey();
2968
2969                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
2970                         WatchedItem::duplicateEntries( $this, $nt );
2971                 }
2972
2973                 # Update search engine
2974                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
2975                 $u->doUpdate();
2976                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
2977                 $u->doUpdate();
2978
2979                 # Update site_stats
2980                 if( $this->isContentPage() && !$nt->isContentPage() ) {
2981                         # No longer a content page
2982                         # Not viewed, edited, removing
2983                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange );
2984                 } elseif( !$this->isContentPage() && $nt->isContentPage() ) {
2985                         # Now a content page
2986                         # Not viewed, edited, adding
2987                         $u = new SiteStatsUpdate( 0, 1, +1, $pageCountChange );
2988                 } elseif( $pageCountChange ) {
2989                         # Redirect added
2990                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
2991                 } else {
2992                         # Nothing special
2993                         $u = false;
2994                 }
2995                 if( $u )
2996                         $u->doUpdate();
2997                 # Update message cache for interface messages
2998                 if( $nt->getNamespace() == NS_MEDIAWIKI ) {
2999                         global $wgMessageCache;
3000
3001                         # @bug 17860: old article can be deleted, if this the case,
3002                         # delete it from message cache
3003                         if ( $this->getArticleID() === 0 ) {
3004                                 $wgMessageCache->replace( $this->getDBkey(), false );
3005                         } else {
3006                                 $oldarticle = new Article( $this );
3007                                 $wgMessageCache->replace( $this->getDBkey(), $oldarticle->getContent() );
3008                         }
3009
3010                         $newarticle = new Article( $nt );
3011                         $wgMessageCache->replace( $nt->getDBkey(), $newarticle->getContent() );
3012                 }
3013
3014                 global $wgUser;
3015                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3016                 return true;
3017         }
3018
3019         /**
3020          * Move page to a title which is at present a redirect to the
3021          * source page
3022          *
3023          * @param $nt \type{Title} the page to move to, which should currently
3024          *  be a redirect
3025          * @param $reason \type{\string} The reason for the move
3026          * @param $createRedirect \type{\bool} Whether to leave a redirect at the old title.
3027          *  Ignored if the user doesn't have the suppressredirect right
3028          */
3029         private function moveOverExistingRedirect( &$nt, $reason = '', $createRedirect = true ) {
3030                 global $wgUseSquid, $wgUser, $wgContLang;
3031
3032                 $comment = wfMsgForContent( '1movedto2_redir', $this->getPrefixedText(), $nt->getPrefixedText() );
3033
3034                 if ( $reason ) {
3035                         $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3036                 }
3037                 # Truncate for whole multibyte characters. +5 bytes for ellipsis
3038                 $comment = $wgContLang->truncate( $comment, 250 );
3039
3040                 $now = wfTimestampNow();
3041                 $newid = $nt->getArticleID();
3042                 $oldid = $this->getArticleID();
3043                 $latest = $this->getLatestRevID();
3044
3045                 $dbw = wfGetDB( DB_MASTER );
3046
3047                 $rcts = $dbw->timestamp( $nt->getEarliestRevTime() );
3048                 $newns = $nt->getNamespace();
3049                 $newdbk = $nt->getDBkey();
3050
3051                 # Delete the old redirect. We don't save it to history since
3052                 # by definition if we've got here it's rather uninteresting.
3053                 # We have to remove it so that the next step doesn't trigger
3054                 # a conflict on the unique namespace+title index...
3055                 $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3056                 if ( !$dbw->cascadingDeletes() ) {
3057                         $dbw->delete( 'revision', array( 'rev_page' => $newid ), __METHOD__ );
3058                         global $wgUseTrackbacks;
3059                         if ($wgUseTrackbacks)
3060                                 $dbw->delete( 'trackbacks', array( 'tb_page' => $newid ), __METHOD__ );
3061                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
3062                         $dbw->delete( 'imagelinks', array( 'il_from' => $newid ), __METHOD__ );
3063                         $dbw->delete( 'categorylinks', array( 'cl_from' => $newid ), __METHOD__ );
3064                         $dbw->delete( 'templatelinks', array( 'tl_from' => $newid ), __METHOD__ );
3065                         $dbw->delete( 'externallinks', array( 'el_from' => $newid ), __METHOD__ );
3066                         $dbw->delete( 'langlinks', array( 'll_from' => $newid ), __METHOD__ );
3067                         $dbw->delete( 'redirect', array( 'rd_from' => $newid ), __METHOD__ );
3068                 }
3069                 // If the redirect was recently created, it may have an entry in recentchanges still
3070                 $dbw->delete( 'recentchanges',
3071                         array( 'rc_timestamp' => $rcts, 'rc_namespace' => $newns, 'rc_title' => $newdbk, 'rc_new' => 1 ),
3072                         __METHOD__
3073                 );
3074
3075                 # Save a null revision in the page's history notifying of the move
3076                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3077                 $nullRevId = $nullRevision->insertOn( $dbw );
3078
3079                 $article = new Article( $this );
3080                 wfRunHooks( 'NewRevisionFromEditComplete', array($article, $nullRevision, $latest, $wgUser) );
3081
3082                 # Change the name of the target page:
3083                 $dbw->update( 'page',
3084                         /* SET */ array(
3085                                 'page_touched'   => $dbw->timestamp($now),
3086                                 'page_namespace' => $nt->getNamespace(),
3087                                 'page_title'     => $nt->getDBkey(),
3088                                 'page_latest'    => $nullRevId,
3089                         ),
3090                         /* WHERE */ array( 'page_id' => $oldid ),
3091                         __METHOD__
3092                 );
3093                 $nt->resetArticleID( $oldid );
3094
3095                 # Recreate the redirect, this time in the other direction.
3096                 if( $createRedirect || !$wgUser->isAllowed('suppressredirect') ) {
3097                         $mwRedir = MagicWord::get( 'redirect' );
3098                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3099                         $redirectArticle = new Article( $this );
3100                         $newid = $redirectArticle->insertOn( $dbw );
3101                         $redirectRevision = new Revision( array(
3102                                 'page'    => $newid,
3103                                 'comment' => $comment,
3104                                 'text'    => $redirectText ) );
3105                         $redirectRevision->insertOn( $dbw );
3106                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3107
3108                         wfRunHooks( 'NewRevisionFromEditComplete', array($redirectArticle, $redirectRevision, false, $wgUser) );
3109
3110                         # Now, we record the link from the redirect to the new title.
3111                         # It should have no other outgoing links...
3112                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
3113                         $dbw->insert( 'pagelinks',
3114                                 array(
3115                                         'pl_from'      => $newid,
3116                                         'pl_namespace' => $nt->getNamespace(),
3117                                         'pl_title'     => $nt->getDBkey() ),
3118                                 __METHOD__ );
3119                         $redirectSuppressed = false;
3120                 } else {
3121                         $this->resetArticleID( 0 );
3122                         $redirectSuppressed = true;
3123                 }
3124
3125                 # Log the move
3126                 $log = new LogPage( 'move' );
3127                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText(), 2 => $redirectSuppressed ) );
3128
3129                 # Purge squid
3130                 if ( $wgUseSquid ) {
3131                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
3132                         $u = new SquidUpdate( $urls );
3133                         $u->doUpdate();
3134                 }
3135
3136         }
3137
3138         /**
3139          * Move page to non-existing title.
3140          *
3141          * @param $nt \type{Title} the new Title
3142          * @param $reason \type{\string} The reason for the move
3143          * @param $createRedirect \type{\bool} Whether to create a redirect from the old title to the new title
3144          *  Ignored if the user doesn't have the suppressredirect right
3145          */
3146         private function moveToNewTitle( &$nt, $reason = '', $createRedirect = true ) {
3147                 global $wgUseSquid, $wgUser, $wgContLang;
3148
3149                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
3150                 if ( $reason ) {
3151                         $comment .= wfMsgExt( 'colon-separator',
3152                                 array( 'escapenoentities', 'content' ) );
3153                         $comment .= $reason;
3154                 }
3155                 # Truncate for whole multibyte characters. +5 bytes for ellipsis
3156                 $comment = $wgContLang->truncate( $comment, 250 );
3157
3158                 $newid = $nt->getArticleID();
3159                 $oldid = $this->getArticleID();
3160                 $latest = $this->getLatestRevId();
3161
3162                 $dbw = wfGetDB( DB_MASTER );
3163                 $now = $dbw->timestamp();
3164
3165                 # Save a null revision in the page's history notifying of the move
3166                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3167                 if ( !is_object( $nullRevision ) ) {
3168                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3169                 }
3170                 $nullRevId = $nullRevision->insertOn( $dbw );
3171
3172                 $article = new Article( $this );
3173                 wfRunHooks( 'NewRevisionFromEditComplete', array($article, $nullRevision, $latest, $wgUser) );
3174
3175                 # Rename page entry
3176                 $dbw->update( 'page',
3177                         /* SET */ array(
3178                                 'page_touched'   => $now,
3179                                 'page_namespace' => $nt->getNamespace(),
3180                                 'page_title'     => $nt->getDBkey(),
3181                                 'page_latest'    => $nullRevId,
3182                         ),
3183                         /* WHERE */ array( 'page_id' => $oldid ),
3184                         __METHOD__
3185                 );
3186                 $nt->resetArticleID( $oldid );
3187
3188                 if( $createRedirect || !$wgUser->isAllowed('suppressredirect') ) {
3189                         # Insert redirect
3190                         $mwRedir = MagicWord::get( 'redirect' );
3191                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3192                         $redirectArticle = new Article( $this );
3193                         $newid = $redirectArticle->insertOn( $dbw );
3194                         $redirectRevision = new Revision( array(
3195                                 'page'    => $newid,
3196                                 'comment' => $comment,
3197                                 'text'    => $redirectText ) );
3198                         $redirectRevision->insertOn( $dbw );
3199                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3200
3201                         wfRunHooks( 'NewRevisionFromEditComplete', array($redirectArticle, $redirectRevision, false, $wgUser) );
3202
3203                         # Record the just-created redirect's linking to the page
3204                         $dbw->insert( 'pagelinks',
3205                                 array(
3206                                         'pl_from'      => $newid,
3207                                         'pl_namespace' => $nt->getNamespace(),
3208                                         'pl_title'     => $nt->getDBkey() ),
3209                                 __METHOD__ );
3210                         $redirectSuppressed = false;
3211                 } else {
3212                         $this->resetArticleID( 0 );
3213                         $redirectSuppressed = true;
3214                 }
3215
3216                 # Log the move
3217                 $log = new LogPage( 'move' );
3218                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText(), 2 => $redirectSuppressed ) );
3219
3220                 # Purge caches as per article creation
3221                 Article::onArticleCreate( $nt );
3222
3223                 # Purge old title from squid
3224                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
3225                 $this->purgeSquid();
3226
3227         }
3228
3229         /**
3230          * Move this page's subpages to be subpages of $nt
3231          *
3232          * @param $nt Title Move target
3233          * @param $auth bool Whether $wgUser's permissions should be checked
3234          * @param $reason string The reason for the move
3235          * @param $createRedirect bool Whether to create redirects from the old subpages to the new ones
3236          *  Ignored if the user doesn't have the 'suppressredirect' right
3237          * @return mixed array with old page titles as keys, and strings (new page titles) or
3238          *  arrays (errors) as values, or an error array with numeric indices if no pages were moved
3239          */
3240         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3241                 global $wgMaximumMovedPages;
3242                 // Check permissions
3243                 if( !$this->userCan( 'move-subpages' ) )
3244                         return array( 'cant-move-subpages' );
3245                 // Do the source and target namespaces support subpages?
3246                 if( !MWNamespace::hasSubpages( $this->getNamespace() ) )
3247                         return array( 'namespace-nosubpages',
3248                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3249                 if( !MWNamespace::hasSubpages( $nt->getNamespace() ) )
3250                         return array( 'namespace-nosubpages',
3251                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3252
3253                 $subpages = $this->getSubpages($wgMaximumMovedPages + 1);
3254                 $retval = array();
3255                 $count = 0;
3256                 foreach( $subpages as $oldSubpage ) {
3257                         $count++;
3258                         if( $count > $wgMaximumMovedPages ) {
3259                                 $retval[$oldSubpage->getPrefixedTitle()] =
3260                                                 array( 'movepage-max-pages',
3261                                                         $wgMaximumMovedPages );
3262                                 break;
3263                         }
3264
3265                         // We don't know whether this function was called before
3266                         // or after moving the root page, so check both
3267                         // $this and $nt
3268                         if( $oldSubpage->getArticleId() == $this->getArticleId() ||
3269                                         $oldSubpage->getArticleID() == $nt->getArticleId() )
3270                                 // When moving a page to a subpage of itself,
3271                                 // don't move it twice
3272                                 continue;
3273                         $newPageName = preg_replace(
3274                                         '#^'.preg_quote( $this->getDBkey(), '#' ).'#',
3275                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3276                                         $oldSubpage->getDBkey() );
3277                         if( $oldSubpage->isTalkPage() ) {
3278                                 $newNs = $nt->getTalkPage()->getNamespace();
3279                         } else {
3280                                 $newNs = $nt->getSubjectPage()->getNamespace();
3281                         }
3282                         # Bug 14385: we need makeTitleSafe because the new page names may
3283                         # be longer than 255 characters.
3284                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3285
3286                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3287                         if( $success === true ) {
3288                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3289                         } else {
3290                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3291                         }
3292                 }
3293                 return $retval;
3294         }
3295
3296         /**
3297          * Checks if this page is just a one-rev redirect.
3298          * Adds lock, so don't use just for light purposes.
3299          *
3300          * @return \type{\bool}
3301          */
3302         public function isSingleRevRedirect() {
3303                 $dbw = wfGetDB( DB_MASTER );
3304                 # Is it a redirect?
3305                 $row = $dbw->selectRow( 'page',
3306                         array( 'page_is_redirect', 'page_latest', 'page_id' ),
3307                         $this->pageCond(),
3308                         __METHOD__,
3309                         array( 'FOR UPDATE' )
3310                 );
3311                 # Cache some fields we may want
3312                 $this->mArticleID = $row ? intval($row->page_id) : 0;
3313                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3314                 $this->mLatestID = $row ? intval($row->page_latest) : false;
3315                 if( !$this->mRedirect ) {
3316                         return false;
3317                 }
3318                 # Does the article have a history?
3319                 $row = $dbw->selectField( array( 'page', 'revision'),
3320                         'rev_id',
3321                         array( 'page_namespace' => $this->getNamespace(),
3322                                 'page_title' => $this->getDBkey(),
3323                                 'page_id=rev_page',
3324                                 'page_latest != rev_id'
3325                         ),
3326                         __METHOD__,
3327                         array( 'FOR UPDATE' )
3328                 );
3329                 # Return true if there was no history
3330                 return ($row === false);
3331         }
3332
3333         /**
3334          * Checks if $this can be moved to a given Title
3335          * - Selects for update, so don't call it unless you mean business
3336          *
3337          * @param $nt \type{Title} the new title to check
3338          * @return \type{\bool} TRUE or FALSE
3339          */
3340         public function isValidMoveTarget( $nt ) {
3341                 $dbw = wfGetDB( DB_MASTER );
3342                 # Is it an existsing file?
3343                 if( $nt->getNamespace() == NS_FILE ) {
3344                         $file = wfLocalFile( $nt );
3345                         if( $file->exists() ) {
3346                                 wfDebug( __METHOD__ . ": file exists\n" );
3347                                 return false;
3348                         }
3349                 }
3350                 # Is it a redirect with no history?
3351                 if( !$nt->isSingleRevRedirect() ) {
3352                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3353                         return false;
3354                 }
3355                 # Get the article text
3356                 $rev = Revision::newFromTitle( $nt );
3357                 $text = $rev->getText();
3358                 # Does the redirect point to the source?
3359                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3360                 $m = array();
3361                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
3362                         $redirTitle = Title::newFromText( $m[1] );
3363                         if( !is_object( $redirTitle ) ||
3364                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3365                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
3366                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3367                                 return false;
3368                         }
3369                 } else {
3370                         # Fail safe
3371                         wfDebug( __METHOD__ . ": failsafe\n" );
3372                         return false;
3373                 }
3374                 return true;
3375         }
3376
3377         /**
3378          * Can this title be added to a user's watchlist?
3379          *
3380          * @return \type{\bool} TRUE or FALSE
3381          */
3382         public function isWatchable() {
3383                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
3384         }
3385
3386         /**
3387          * Get categories to which this Title belongs and return an array of
3388          * categories' names.
3389          *
3390          * @return \type{\array} array an array of parents in the form:
3391          *      $parent => $currentarticle
3392          */
3393         public function getParentCategories() {
3394                 global $wgContLang;
3395
3396                 $titlekey = $this->getArticleId();
3397                 $dbr = wfGetDB( DB_SLAVE );
3398                 $categorylinks = $dbr->tableName( 'categorylinks' );
3399
3400                 # NEW SQL
3401                 $sql = "SELECT * FROM $categorylinks"
3402                      ." WHERE cl_from='$titlekey'"
3403                          ." AND cl_from <> '0'"
3404                          ." ORDER BY cl_sortkey";
3405
3406                 $res = $dbr->query( $sql );
3407
3408                 if( $dbr->numRows( $res ) > 0 ) {
3409                         foreach( $res as $row )
3410                                 //$data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
3411                                 $data[$wgContLang->getNSText( NS_CATEGORY ).':'.$row->cl_to] = $this->getFullText();
3412                         $dbr->freeResult( $res );
3413                 } else {
3414                         $data = array();
3415                 }
3416                 return $data;
3417         }
3418
3419         /**
3420          * Get a tree of parent categories
3421          *
3422          * @param $children \type{\array} an array with the children in the keys, to check for circular refs
3423          * @return \type{\array} Tree of parent categories
3424          */
3425         public function getParentCategoryTree( $children = array() ) {
3426                 $stack = array();
3427                 $parents = $this->getParentCategories();
3428
3429                 if( $parents ) {
3430                         foreach( $parents as $parent => $current ) {
3431                                 if ( array_key_exists( $parent, $children ) ) {
3432                                         # Circular reference
3433                                         $stack[$parent] = array();
3434                                 } else {
3435                                         $nt = Title::newFromText($parent);
3436                                         if ( $nt ) {
3437                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array($parent => 1) );
3438                                         }
3439                                 }
3440                         }
3441                         return $stack;
3442                 } else {
3443                         return array();
3444                 }
3445         }
3446
3447
3448         /**
3449          * Get an associative array for selecting this title from
3450          * the "page" table
3451          *
3452          * @return \type{\array} Selection array
3453          */
3454         public function pageCond() {
3455                 if( $this->mArticleID > 0 ) {
3456                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
3457                         return array( 'page_id' => $this->mArticleID );
3458                 } else {
3459                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
3460                 }
3461         }
3462
3463         /**
3464          * Get the revision ID of the previous revision
3465          *
3466          * @param $revId \type{\int} Revision ID. Get the revision that was before this one.
3467          * @param $flags \type{\int} GAID_FOR_UPDATE
3468          * @return \twotypes{\int,\bool} Old revision ID, or FALSE if none exists
3469          */
3470         public function getPreviousRevisionID( $revId, $flags=0 ) {
3471                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3472                 return $db->selectField( 'revision', 'rev_id',
3473                         array(
3474                                 'rev_page' => $this->getArticleId($flags),
3475                                 'rev_id < ' . intval( $revId )
3476                         ),
3477                         __METHOD__,
3478                         array( 'ORDER BY' => 'rev_id DESC' )
3479                 );
3480         }
3481
3482         /**
3483          * Get the revision ID of the next revision
3484          *
3485          * @param $revId \type{\int} Revision ID. Get the revision that was after this one.
3486          * @param $flags \type{\int} GAID_FOR_UPDATE
3487          * @return \twotypes{\int,\bool} Next revision ID, or FALSE if none exists
3488          */
3489         public function getNextRevisionID( $revId, $flags=0 ) {
3490                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3491                 return $db->selectField( 'revision', 'rev_id',
3492                         array(
3493                                 'rev_page' => $this->getArticleId($flags),
3494                                 'rev_id > ' . intval( $revId )
3495                         ),
3496                         __METHOD__,
3497                         array( 'ORDER BY' => 'rev_id' )
3498                 );
3499         }
3500
3501         /**
3502          * Get the first revision of the page
3503          *
3504          * @param $flags \type{\int} GAID_FOR_UPDATE
3505          * @return Revision (or NULL if page doesn't exist)
3506          */
3507         public function getFirstRevision( $flags=0 ) {
3508                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3509                 $pageId = $this->getArticleId($flags);
3510                 if( !$pageId ) return null;
3511                 $row = $db->selectRow( 'revision', '*',
3512                         array( 'rev_page' => $pageId ),
3513                         __METHOD__,
3514                         array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
3515                 );
3516                 if( !$row ) {
3517                         return null;
3518                 } else {
3519                         return new Revision( $row );
3520                 }
3521         }
3522
3523         /**
3524          * Check if this is a new page
3525          *
3526          * @return bool
3527          */
3528         public function isNewPage() {
3529                 $dbr = wfGetDB( DB_SLAVE );
3530                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
3531         }
3532
3533         /**
3534          * Get the oldest revision timestamp of this page
3535          *
3536          * @return String: MW timestamp
3537          */
3538         public function getEarliestRevTime() {
3539                 $dbr = wfGetDB( DB_SLAVE );
3540                 if( $this->exists() ) {
3541                         $min = $dbr->selectField( 'revision',
3542                                 'MIN(rev_timestamp)',
3543                                 array( 'rev_page' => $this->getArticleId() ),
3544                                 __METHOD__ );
3545                         return wfTimestampOrNull( TS_MW, $min );
3546                 }
3547                 return null;
3548         }
3549
3550         /**
3551          * Get the number of revisions between the given revision IDs.
3552          * Used for diffs and other things that really need it.
3553          *
3554          * @param $old \type{\int} Revision ID.
3555          * @param $new \type{\int} Revision ID.
3556          * @return \type{\int} Number of revisions between these IDs.
3557          */
3558         public function countRevisionsBetween( $old, $new ) {
3559                 $dbr = wfGetDB( DB_SLAVE );
3560                 return (int)$dbr->selectField( 'revision', 'count(*)',
3561                         'rev_page = ' . intval( $this->getArticleId() ) .
3562                         ' AND rev_id > ' . intval( $old ) .
3563                         ' AND rev_id < ' . intval( $new ),
3564                         __METHOD__
3565                 );
3566         }
3567
3568         /**
3569          * Compare with another title.
3570          *
3571          * @param $title \type{Title}
3572          * @return \type{\bool} TRUE or FALSE
3573          */
3574         public function equals( Title $title ) {
3575                 // Note: === is necessary for proper matching of number-like titles.
3576                 return $this->getInterwiki() === $title->getInterwiki()
3577                         && $this->getNamespace() == $title->getNamespace()
3578                         && $this->getDBkey() === $title->getDBkey();
3579         }
3580
3581         /**
3582          * Callback for usort() to do title sorts by (namespace, title)
3583          *
3584          * @return Integer: result of string comparison, or namespace comparison
3585          */
3586         public static function compare( $a, $b ) {
3587                 if( $a->getNamespace() == $b->getNamespace() ) {
3588                         return strcmp( $a->getText(), $b->getText() );
3589                 } else {
3590                         return $a->getNamespace() - $b->getNamespace();
3591                 }
3592         }
3593
3594         /**
3595          * Return a string representation of this title
3596          *
3597          * @return \type{\string} String representation of this title
3598          */
3599         public function __toString() {
3600                 return $this->getPrefixedText();
3601         }
3602
3603         /**
3604          * Check if page exists.  For historical reasons, this function simply
3605          * checks for the existence of the title in the page table, and will
3606          * thus return false for interwiki links, special pages and the like.
3607          * If you want to know if a title can be meaningfully viewed, you should
3608          * probably call the isKnown() method instead.
3609          *
3610          * @return \type{\bool}
3611          */
3612         public function exists() {
3613                 return $this->getArticleId() != 0;
3614         }
3615
3616         /**
3617          * Should links to this title be shown as potentially viewable (i.e. as
3618          * "bluelinks"), even if there's no record by this title in the page
3619          * table?
3620          *
3621          * This function is semi-deprecated for public use, as well as somewhat
3622          * misleadingly named.  You probably just want to call isKnown(), which
3623          * calls this function internally.
3624          *
3625          * (ISSUE: Most of these checks are cheap, but the file existence check
3626          * can potentially be quite expensive.  Including it here fixes a lot of
3627          * existing code, but we might want to add an optional parameter to skip
3628          * it and any other expensive checks.)
3629          *
3630          * @return \type{\bool}
3631          */
3632         public function isAlwaysKnown() {
3633                 if( $this->mInterwiki != '' ) {
3634                         return true;  // any interwiki link might be viewable, for all we know
3635                 }
3636                 switch( $this->mNamespace ) {
3637                 case NS_MEDIA:
3638                 case NS_FILE:
3639                         return wfFindFile( $this );  // file exists, possibly in a foreign repo
3640                 case NS_SPECIAL:
3641                         return SpecialPage::exists( $this->getDBkey() );  // valid special page
3642                 case NS_MAIN:
3643                         return $this->mDbkeyform == '';  // selflink, possibly with fragment
3644                 case NS_MEDIAWIKI:
3645                         // If the page is form Mediawiki:message/lang, calling wfMsgWeirdKey causes
3646                         // the full l10n of that language to be loaded. That takes much memory and
3647                         // isn't needed. So we strip the language part away.
3648                         list( $basename, /* rest */ ) = explode( '/', $this->mDbkeyform, 2 );
3649                         return (bool)wfMsgWeirdKey( $basename );  // known system message
3650                 default:
3651                         return false;
3652                 }
3653         }
3654
3655         /**
3656          * Does this title refer to a page that can (or might) be meaningfully
3657          * viewed?  In particular, this function may be used to determine if
3658          * links to the title should be rendered as "bluelinks" (as opposed to
3659          * "redlinks" to non-existent pages).
3660          *
3661          * @return \type{\bool}
3662          */
3663         public function isKnown() {
3664                 return $this->exists() || $this->isAlwaysKnown();
3665         }
3666
3667         /**
3668          * Does this page have source text?
3669          *
3670          * @return Boolean
3671          */
3672         public function hasSourceText() {
3673                 if ( $this->exists() )
3674                         return true;
3675
3676                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
3677                         // If the page doesn't exist but is a known system message, default
3678                         // message content will be displayed, same for language subpages
3679                         // Also, if the page is form Mediawiki:message/lang, calling wfMsgWeirdKey
3680                         // causes the full l10n of that language to be loaded. That takes much
3681                         // memory and isn't needed. So we strip the language part away.
3682                         list( $basename, /* rest */ ) = explode( '/', $this->mDbkeyform, 2 );
3683                         return (bool)wfMsgWeirdKey( $basename );
3684                 }
3685
3686                 return false;
3687         }
3688
3689         /**
3690         * Is this in a namespace that allows actual pages?
3691         *
3692         * @return \type{\bool}
3693         * @internal note -- uses hardcoded namespace index instead of constants
3694         */
3695         public function canExist() {
3696                 return $this->mNamespace >=0 && $this->mNamespace != NS_MEDIA;
3697         }
3698
3699         /**
3700          * Update page_touched timestamps and send squid purge messages for
3701          * pages linking to this title. May be sent to the job queue depending
3702          * on the number of links. Typically called on create and delete.
3703          */
3704         public function touchLinks() {
3705                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
3706                 $u->doUpdate();
3707
3708                 if ( $this->getNamespace() == NS_CATEGORY ) {
3709                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
3710                         $u->doUpdate();
3711                 }
3712         }
3713
3714         /**
3715          * Get the last touched timestamp
3716          *
3717          * @param $db DatabaseBase: optional db
3718          * @return \type{\string} Last touched timestamp
3719          */
3720         public function getTouched( $db = null ) {
3721                 $db = isset($db) ? $db : wfGetDB( DB_SLAVE );
3722                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
3723                 return $touched;
3724         }
3725
3726         /**
3727          * Get the timestamp when this page was updated since the user last saw it.
3728          *
3729          * @param $user User
3730          * @return Mixed: string/null
3731          */
3732         public function getNotificationTimestamp( $user = null ) {
3733                 global $wgUser, $wgShowUpdatedMarker;
3734                 // Assume current user if none given
3735                 if( !$user ) $user = $wgUser;
3736                 // Check cache first
3737                 $uid = $user->getId();
3738                 if( isset($this->mNotificationTimestamp[$uid]) ) {
3739                         return $this->mNotificationTimestamp[$uid];
3740                 }
3741                 if( !$uid || !$wgShowUpdatedMarker ) {
3742                         return $this->mNotificationTimestamp[$uid] = false;
3743                 }
3744                 // Don't cache too much!
3745                 if( count($this->mNotificationTimestamp) >= self::CACHE_MAX ) {
3746                         $this->mNotificationTimestamp = array();
3747                 }
3748                 $dbr = wfGetDB( DB_SLAVE );
3749                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
3750                         'wl_notificationtimestamp',
3751                         array( 'wl_namespace' => $this->getNamespace(),
3752                                 'wl_title' => $this->getDBkey(),
3753                                 'wl_user' => $user->getId()
3754                         ),
3755                         __METHOD__
3756                 );
3757                 return $this->mNotificationTimestamp[$uid];
3758         }
3759
3760         /**
3761          * Get the trackback URL for this page
3762          *
3763          * @return \type{\string} Trackback URL
3764          */
3765         public function trackbackURL() {
3766                 global $wgScriptPath, $wgServer, $wgScriptExtension;
3767
3768                 return "$wgServer$wgScriptPath/trackback$wgScriptExtension?article="
3769                         . htmlspecialchars(urlencode($this->getPrefixedDBkey()));
3770         }
3771
3772         /**
3773          * Get the trackback RDF for this page
3774          *
3775          * @return \type{\string} Trackback RDF
3776          */
3777         public function trackbackRDF() {
3778                 $url = htmlspecialchars($this->getFullURL());
3779                 $title = htmlspecialchars($this->getText());
3780                 $tburl = $this->trackbackURL();
3781
3782                 // Autodiscovery RDF is placed in comments so HTML validator
3783                 // won't barf. This is a rather icky workaround, but seems
3784                 // frequently used by this kind of RDF thingy.
3785                 //
3786                 // Spec: http://www.sixapart.com/pronet/docs/trackback_spec
3787                 return "<!--
3788 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
3789          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
3790          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
3791 <rdf:Description
3792    rdf:about=\"$url\"
3793    dc:identifier=\"$url\"
3794    dc:title=\"$title\"
3795    trackback:ping=\"$tburl\" />
3796 </rdf:RDF>
3797 -->";
3798         }
3799
3800         /**
3801          * Generate strings used for xml 'id' names in monobook tabs
3802          *
3803          * @param $prepend string defaults to 'nstab-'
3804          * @return \type{\string} XML 'id' name
3805          */
3806         public function getNamespaceKey( $prepend = 'nstab-' ) {
3807                 global $wgContLang;
3808                 // Gets the subject namespace if this title
3809                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
3810                 // Checks if cononical namespace name exists for namespace
3811                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
3812                         // Uses canonical namespace name
3813                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
3814                 } else {
3815                         // Uses text of namespace
3816                         $namespaceKey = $this->getSubjectNsText();
3817                 }
3818                 // Makes namespace key lowercase
3819                 $namespaceKey = $wgContLang->lc( $namespaceKey );
3820                 // Uses main
3821                 if ( $namespaceKey == '' ) {
3822                         $namespaceKey = 'main';
3823                 }
3824                 // Changes file to image for backwards compatibility
3825                 if ( $namespaceKey == 'file' ) {
3826                         $namespaceKey = 'image';
3827                 }
3828                 return $prepend . $namespaceKey;
3829         }
3830
3831         /**
3832          * Returns true if this is a special page.
3833          *
3834          * @return boolean
3835          */
3836         public function isSpecialPage( ) {
3837                 return $this->getNamespace() == NS_SPECIAL;
3838         }
3839
3840         /**
3841          * Returns true if this title resolves to the named special page
3842          *
3843          * @param $name \type{\string} The special page name
3844          * @return boolean
3845          */
3846         public function isSpecial( $name ) {
3847                 if ( $this->getNamespace() == NS_SPECIAL ) {
3848                         list( $thisName, /* $subpage */ ) = SpecialPage::resolveAliasWithSubpage( $this->getDBkey() );
3849                         if ( $name == $thisName ) {
3850                                 return true;
3851                         }
3852                 }
3853                 return false;
3854         }
3855
3856         /**
3857          * If the Title refers to a special page alias which is not the local default,
3858          *
3859          * @return \type{Title} A new Title which points to the local default.
3860          *         Otherwise, returns $this.
3861          */
3862         public function fixSpecialName() {
3863                 if ( $this->getNamespace() == NS_SPECIAL ) {
3864                         $canonicalName = SpecialPage::resolveAlias( $this->mDbkeyform );
3865                         if ( $canonicalName ) {
3866                                 $localName = SpecialPage::getLocalNameFor( $canonicalName );
3867                                 if ( $localName != $this->mDbkeyform ) {
3868                                         return Title::makeTitle( NS_SPECIAL, $localName );
3869                                 }
3870                         }
3871                 }
3872                 return $this;
3873         }
3874
3875         /**
3876          * Is this Title in a namespace which contains content?
3877          * In other words, is this a content page, for the purposes of calculating
3878          * statistics, etc?
3879          *
3880          * @return \type{\bool}
3881          */
3882         public function isContentPage() {
3883                 return MWNamespace::isContent( $this->getNamespace() );
3884         }
3885
3886         /**
3887          * Get all extant redirects to this Title
3888          *
3889          * @param $ns \twotypes{\int,\null} Single namespace to consider;
3890          *            NULL to consider all namespaces
3891          * @return \type{\arrayof{Title}} Redirects to this title
3892          */
3893         public function getRedirectsHere( $ns = null ) {
3894                 $redirs = array();
3895
3896                 $dbr = wfGetDB( DB_SLAVE );
3897                 $where = array(
3898                         'rd_namespace' => $this->getNamespace(),
3899                         'rd_title' => $this->getDBkey(),
3900                         'rd_from = page_id'
3901                 );
3902                 if ( !is_null($ns) ) $where['page_namespace'] = $ns;
3903
3904                 $res = $dbr->select(
3905                         array( 'redirect', 'page' ),
3906                         array( 'page_namespace', 'page_title' ),
3907                         $where,
3908                         __METHOD__
3909                 );
3910
3911
3912                 foreach( $res as $row ) {
3913                         $redirs[] = self::newFromRow( $row );
3914                 }
3915                 return $redirs;
3916         }
3917
3918         /**
3919          * Check if this Title is a valid redirect target
3920          *
3921          * @return \type{\bool}
3922          */
3923         public function isValidRedirectTarget() {
3924                 global $wgInvalidRedirectTargets;
3925
3926                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
3927                 if( $this->isSpecial( 'Userlogout' ) ) {
3928                         return false;
3929                 }
3930
3931                 foreach( $wgInvalidRedirectTargets as $target ) {
3932                         if( $this->isSpecial( $target ) ) {
3933                                 return false;
3934                         }
3935                 }
3936
3937                 return true;
3938         }
3939
3940         /**
3941          * Get a backlink cache object
3942          *
3943          * @return object BacklinkCache
3944          */
3945         function getBacklinkCache() {
3946                 if ( is_null( $this->mBacklinkCache ) ) {
3947                         $this->mBacklinkCache = new BacklinkCache( $this );
3948                 }
3949                 return $this->mBacklinkCache;
3950         }
3951
3952         /**
3953          * Whether the magic words __INDEX__ and __NOINDEX__ function for
3954          * this page.
3955          *
3956          * @return Boolean
3957          */
3958         public function canUseNoindex(){
3959                 global $wgArticleRobotPolicies, $wgContentNamespaces,
3960                        $wgExemptFromUserRobotsControl;
3961
3962                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
3963                         ? $wgContentNamespaces
3964                         : $wgExemptFromUserRobotsControl;
3965
3966                 return !in_array( $this->mNamespace, $bannedNamespaces );
3967
3968         }
3969
3970         /**
3971          * Returns restriction types for the current Title
3972          *
3973          * @return array applicable restriction types
3974          */
3975         public function getRestrictionTypes() {
3976                 global $wgRestrictionTypes;
3977                 $types = $this->exists() ? $wgRestrictionTypes : array('create');
3978
3979                 if ( $this->getNamespace() == NS_FILE ) {
3980                         $types[] = 'upload';
3981                 }
3982
3983                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
3984
3985                 return $types;
3986         }
3987 }