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