includes/Title.php

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