includes/Title.php

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