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
1137                         // unstub $wgUser here and set $user = $wgUser
1138                         global $wgUser;
1139                         $wgUser->_unstub( '', 5 );
1140                         $user = $wgUser;
1141                 }
1142
1143                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1144
1145                 // Remove the errors being ignored.
1146                 foreach ( $errors as $index => $error ) {
1147                         $error_key = is_array( $error ) ? $error[0] : $error;
1148
1149                         if ( in_array( $error_key, $ignoreErrors ) ) {
1150                                 unset( $errors[$index] );
1151                         }
1152                 }
1153
1154                 return $errors;
1155         }
1156
1157         /**
1158          * Permissions checks that fail most often, and which are easiest to test.
1159          *
1160          * @param $action String the action to check
1161          * @param $user User user to check
1162          * @param $errors Array list of current errors
1163          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1164          * @param $short Boolean short circuit on first error
1165          *
1166          * @return Array list of errors
1167          */
1168         private function checkQuickPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1169                 if ( $action == 'create' ) {
1170                         if ( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1171                                  ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1172                                 $errors[] = $user->isAnon() ? array ( 'nocreatetext' ) : array ( 'nocreate-loggedin' );
1173                         }
1174                 } elseif ( $action == 'move' ) {
1175                         if ( !$user->isAllowed( 'move-rootuserpages' )
1176                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1177                                 // Show user page-specific message only if the user can move other pages
1178                                 $errors[] = array( 'cant-move-user-page' );
1179                         }
1180
1181                         // Check if user is allowed to move files if it's a file
1182                         if ( $this->mNamespace == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1183                                 $errors[] = array( 'movenotallowedfile' );
1184                         }
1185
1186                         if ( !$user->isAllowed( 'move' ) ) {
1187                                 // User can't move anything
1188                                 global $wgGroupPermissions;
1189                                 $userCanMove = false;
1190                                 if ( isset( $wgGroupPermissions['user']['move'] ) ) {
1191                                         $userCanMove = $wgGroupPermissions['user']['move'];
1192                                 }
1193                                 $autoconfirmedCanMove = false;
1194                                 if ( isset( $wgGroupPermissions['autoconfirmed']['move'] ) ) {
1195                                         $autoconfirmedCanMove = $wgGroupPermissions['autoconfirmed']['move'];
1196                                 }
1197                                 if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
1198                                         // custom message if logged-in users without any special rights can move
1199                                         $errors[] = array ( 'movenologintext' );
1200                                 } else {
1201                                         $errors[] = array ( 'movenotallowed' );
1202                                 }
1203                         }
1204                 } elseif ( $action == 'move-target' ) {
1205                         if ( !$user->isAllowed( 'move' ) ) {
1206                                 // User can't move anything
1207                                 $errors[] = array ( 'movenotallowed' );
1208                         } elseif ( !$user->isAllowed( 'move-rootuserpages' )
1209                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1210                                 // Show user page-specific message only if the user can move other pages
1211                                 $errors[] = array( 'cant-move-to-user-page' );
1212                         }
1213                 } elseif ( !$user->isAllowed( $action ) ) {
1214                         $return = null;
1215
1216                         // We avoid expensive display logic for quickUserCan's and such
1217                         $groups = false;
1218                         if ( !$short ) {
1219                                 $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
1220                                         User::getGroupsWithPermission( $action ) );
1221                         }
1222
1223                         if ( $groups ) {
1224                                 global $wgLang;
1225                                 $return = array(
1226                                         'badaccess-groups',
1227                                         $wgLang->commaList( $groups ),
1228                                         count( $groups )
1229                                 );
1230                         } else {
1231                                 $return = array( "badaccess-group0" );
1232                         }
1233                         $errors[] = $return;
1234                 }
1235
1236                 return $errors;
1237         }
1238
1239         /**
1240          * Add the resulting error code to the errors array
1241          *
1242          * @param $errors Array list of current errors
1243          * @param $result Mixed result of errors
1244          *
1245          * @return Array list of errors
1246          */
1247         private function resultToError( $errors, $result ) {
1248                 if ( is_array( $result ) && count( $result ) && !is_array( $result[0] ) ) {
1249                         // A single array representing an error
1250                         $errors[] = $result;
1251                 } else if ( is_array( $result ) && is_array( $result[0] ) ) {
1252                         // A nested array representing multiple errors
1253                         $errors = array_merge( $errors, $result );
1254                 } else if ( $result !== '' && is_string( $result ) ) {
1255                         // A string representing a message-id
1256                         $errors[] = array( $result );
1257                 } else if ( $result === false ) {
1258                         // a generic "We don't want them to do that"
1259                         $errors[] = array( 'badaccess-group0' );
1260                 }
1261                 return $errors;
1262         }
1263
1264         /**
1265          * Check various permission hooks
1266          * @see checkQuickPermissions for parameter information
1267          */
1268         private function checkPermissionHooks( $action, $user, $errors, $doExpensiveQueries, $short ) {
1269                 // Use getUserPermissionsErrors instead
1270                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1271                         return $result ? array() : array( array( 'badaccess-group0' ) );
1272                 }
1273                 // Check getUserPermissionsErrors hook
1274                 if ( !wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1275                         $errors = $this->resultToError( $errors, $result );
1276                 }
1277                 // Check getUserPermissionsErrorsExpensive hook
1278                 if ( $doExpensiveQueries && !( $short && count( $errors ) > 0 ) &&
1279                          !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) ) ) {
1280                         $errors = $this->resultToError( $errors, $result );
1281                 }
1282
1283                 return $errors;
1284         }
1285
1286         /**
1287          * Check permissions on special pages & namespaces
1288          * @see checkQuickPermissions for parameter information
1289          */
1290         private function checkSpecialsAndNSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1291                 # Only 'createaccount' and 'execute' can be performed on
1292                 # special pages, which don't actually exist in the DB.
1293                 $specialOKActions = array( 'createaccount', 'execute' );
1294                 if ( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions ) ) {
1295                         $errors[] = array( 'ns-specialprotected' );
1296                 }
1297
1298                 # Check $wgNamespaceProtection for restricted namespaces
1299                 if ( $this->isNamespaceProtected() ) {
1300                         $ns = $this->mNamespace == NS_MAIN ?
1301                                 wfMsg( 'nstab-main' ) : $this->getNsText();
1302                         $errors[] = $this->mNamespace == NS_MEDIAWIKI ?
1303                                 array( 'protectedinterface' ) : array( 'namespaceprotected',  $ns );
1304                 }
1305
1306                 return $errors;
1307         }
1308
1309         /**
1310          * Check CSS/JS sub-page permissions
1311          * @see checkQuickPermissions for parameter information
1312          */
1313         private function checkCSSandJSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1314                 # Protect css/js subpages of user pages
1315                 # XXX: this might be better using restrictions
1316                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssSubpage()
1317                 #      and $this->userCanEditJsSubpage() from working
1318                 # XXX: right 'editusercssjs' is deprecated, for backward compatibility only
1319                 if ( $action != 'patrol' && !$user->isAllowed( 'editusercssjs' )
1320                                 && !preg_match( '/^' . preg_quote( $user->getName(), '/' ) . '\//', $this->mTextform ) ) {
1321                         if ( $this->isCssSubpage() && !$user->isAllowed( 'editusercss' ) ) {
1322                                 $errors[] = array( 'customcssjsprotected' );
1323                         } else if ( $this->isJsSubpage() && !$user->isAllowed( 'edituserjs' ) ) {
1324                                 $errors[] = array( 'customcssjsprotected' );
1325                         }
1326                 }
1327
1328                 return $errors;
1329         }
1330
1331         /**
1332          * Check against page_restrictions table requirements on this
1333          * page. The user must possess all required rights for this
1334          * action.
1335          * @see checkQuickPermissions for parameter information
1336          */
1337         private function checkPageRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1338                 foreach ( $this->getRestrictions( $action ) as $right ) {
1339                         // Backwards compatibility, rewrite sysop -> protect
1340                         if ( $right == 'sysop' ) {
1341                                 $right = 'protect';
1342                         }
1343                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1344                                 // Users with 'editprotected' permission can edit protected pages
1345                                 if ( $action == 'edit' && $user->isAllowed( 'editprotected' ) ) {
1346                                         // Users with 'editprotected' permission cannot edit protected pages
1347                                         // with cascading option turned on.
1348                                         if ( $this->mCascadeRestriction ) {
1349                                                 $errors[] = array( 'protectedpagetext', $right );
1350                                         }
1351                                 } else {
1352                                         $errors[] = array( 'protectedpagetext', $right );
1353                                 }
1354                         }
1355                 }
1356
1357                 return $errors;
1358         }
1359
1360         /**
1361          * Check restrictions on cascading pages.
1362          * @see checkQuickPermissions for parameter information
1363          */
1364         private function checkCascadingSourcesRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1365                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1366                         # We /could/ use the protection level on the source page, but it's
1367                         # fairly ugly as we have to establish a precedence hierarchy for pages
1368                         # included by multiple cascade-protected pages. So just restrict
1369                         # it to people with 'protect' permission, as they could remove the
1370                         # protection anyway.
1371                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1372                         # Cascading protection depends on more than this page...
1373                         # Several cascading protected pages may include this page...
1374                         # Check each cascading level
1375                         # This is only for protection restrictions, not for all actions
1376                         if ( isset( $restrictions[$action] ) ) {
1377                                 foreach ( $restrictions[$action] as $right ) {
1378                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1379                                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1380                                                 $pages = '';
1381                                                 foreach ( $cascadingSources as $page )
1382                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1383                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1384                                         }
1385                                 }
1386                         }
1387                 }
1388
1389                 return $errors;
1390         }
1391
1392         /**
1393          * Check action permissions not already checked in checkQuickPermissions
1394          * @see checkQuickPermissions for parameter information
1395          */
1396         private function checkActionPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1397                 if ( $action == 'protect' ) {
1398                         if ( $this->getUserPermissionsErrors( 'edit', $user ) != array() ) {
1399                                 // If they can't edit, they shouldn't protect.
1400                                 $errors[] = array( 'protect-cantedit' );
1401                         }
1402                 } elseif ( $action == 'create' ) {
1403                         $title_protection = $this->getTitleProtection();
1404                         if( $title_protection ) {
1405                                 if( $title_protection['pt_create_perm'] == 'sysop' ) {
1406                                         $title_protection['pt_create_perm'] = 'protect'; // B/C
1407                                 }
1408                                 if( $title_protection['pt_create_perm'] == '' || !$user->isAllowed( $title_protection['pt_create_perm'] ) ) {
1409                                         $errors[] = array( 'titleprotected', User::whoIs( $title_protection['pt_user'] ), $title_protection['pt_reason'] );
1410                                 }
1411                         }
1412                 } elseif ( $action == 'move' ) {
1413                         // Check for immobile pages
1414                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1415                                 // Specific message for this case
1416                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1417                         } elseif ( !$this->isMovable() ) {
1418                                 // Less specific message for rarer cases
1419                                 $errors[] = array( 'immobile-page' );
1420                         }
1421                 } elseif ( $action == 'move-target' ) {
1422                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1423                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1424                         } elseif ( !$this->isMovable() ) {
1425                                 $errors[] = array( 'immobile-target-page' );
1426                         }
1427                 }
1428                 return $errors;
1429         }
1430
1431         /**
1432          * Check that the user isn't blocked from editting.
1433          * @see checkQuickPermissions for parameter information
1434          */
1435         private function checkUserBlock( $action, $user, $errors, $doExpensiveQueries, $short ) {
1436                 if( $short ) {
1437                         return $errors;
1438                 }
1439
1440                 global $wgContLang;
1441                 global $wgLang;
1442                 global $wgEmailConfirmToEdit;
1443
1444                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() && $action != 'createaccount' ) {
1445                         $errors[] = array( 'confirmedittext' );
1446                 }
1447
1448                 // Edit blocks should not affect reading. Account creation blocks handled at userlogin.
1449                 if ( $action != 'read' && $action != 'createaccount' && $user->isBlockedFrom( $this ) ) {
1450                         $block = $user->mBlock;
1451
1452                         // This is from OutputPage::blockedPage
1453                         // Copied at r23888 by werdna
1454
1455                         $id = $user->blockedBy();
1456                         $reason = $user->blockedFor();
1457                         if ( $reason == '' ) {
1458                                 $reason = wfMsg( 'blockednoreason' );
1459                         }
1460                         $ip = wfGetIP();
1461
1462                         if ( is_numeric( $id ) ) {
1463                                 $name = User::whoIs( $id );
1464                         } else {
1465                                 $name = $id;
1466                         }
1467
1468                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1469                         $blockid = $block->mId;
1470                         $blockExpiry = $user->mBlock->mExpiry;
1471                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $user->mBlock->mTimestamp ), true );
1472                         if ( $blockExpiry == 'infinity' ) {
1473                                 // Entry in database (table ipblocks) is 'infinity' but 'ipboptions' uses 'infinite' or 'indefinite'
1474                                 $scBlockExpiryOptions = wfMsg( 'ipboptions' );
1475
1476                                 foreach ( explode( ',', $scBlockExpiryOptions ) as $option ) {
1477                                         if ( strpos( $option, ':' ) == false )
1478                                                 continue;
1479
1480                                         list ( $show, $value ) = explode( ":", $option );
1481
1482                                         if ( $value == 'infinite' || $value == 'indefinite' ) {
1483                                                 $blockExpiry = $show;
1484                                                 break;
1485                                         }
1486                                 }
1487                         } else {
1488                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1489                         }
1490
1491                         $intended = $user->mBlock->mAddress;
1492
1493                         $errors[] = array( ( $block->mAuto ? 'autoblockedtext' : 'blockedtext' ), $link, $reason, $ip, $name,
1494                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
1495                 }
1496
1497                 return $errors;
1498         }
1499
1500         /**
1501          * Can $user perform $action on this page? This is an internal function,
1502          * which checks ONLY that previously checked by userCan (i.e. it leaves out
1503          * checks on wfReadOnly() and blocks)
1504          *
1505          * @param $action \type{\string} action that permission needs to be checked for
1506          * @param $user \type{User} user to check
1507          * @param $doExpensiveQueries \type{\bool} Set this to false to avoid doing unnecessary queries.
1508          * @param $short \type{\bool} Set this to true to stop after the first permission error.
1509          * @return \type{\array} Array of arrays of the arguments to wfMsg to explain permissions problems.
1510          */
1511         protected function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true, $short = false ) {
1512                 wfProfileIn( __METHOD__ );
1513
1514                 $errors = array();
1515                 $checks = array( 'checkQuickPermissions',
1516                         'checkPermissionHooks',
1517                         'checkSpecialsAndNSPermissions',
1518                         'checkCSSandJSPermissions',
1519                         'checkPageRestrictions',
1520                         'checkCascadingSourcesRestrictions',
1521                         'checkActionPermissions',
1522                         'checkUserBlock' );
1523
1524                 while( count( $checks ) > 0 &&
1525                            !( $short && count( $errors ) > 0 ) ) {
1526                         $method = array_shift( $checks );
1527                         $errors = $this->$method( $action, $user, $errors, $doExpensiveQueries, $short );
1528                 }
1529
1530                 wfProfileOut( __METHOD__ );
1531                 return $errors;
1532         }
1533
1534         /**
1535          * Is this title subject to title protection?
1536          *
1537          * @return \type{\mixed} An associative array representing any existent title
1538          *   protection, or false if there's none.
1539          */
1540         private function getTitleProtection() {
1541                 // Can't protect pages in special namespaces
1542                 if ( $this->getNamespace() < 0 ) {
1543                         return false;
1544                 }
1545
1546                 // Can't protect pages that exist.
1547                 if ( $this->exists() ) {
1548                         return false;
1549                 }
1550
1551                 if ( !isset( $this->mTitleProtection ) ) {
1552                         $dbr = wfGetDB( DB_SLAVE );
1553                         $res = $dbr->select( 'protected_titles', '*',
1554                                 array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
1555                                 __METHOD__ );
1556
1557                         // fetchRow returns false if there are no rows.
1558                         $this->mTitleProtection = $dbr->fetchRow( $res );
1559                 }
1560                 return $this->mTitleProtection;
1561         }
1562
1563         /**
1564          * Update the title protection status
1565          *
1566          * @param $create_perm \type{\string} Permission required for creation
1567          * @param $reason \type{\string} Reason for protection
1568          * @param $expiry \type{\string} Expiry timestamp
1569          * @return boolean true
1570          */
1571         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
1572                 global $wgUser, $wgContLang;
1573
1574                 if ( $create_perm == implode( ',', $this->getRestrictions( 'create' ) )
1575                         && $expiry == $this->mRestrictionsExpiry['create'] ) {
1576                         // No change
1577                         return true;
1578                 }
1579
1580                 list ( $namespace, $title ) = array( $this->getNamespace(), $this->getDBkey() );
1581
1582                 $dbw = wfGetDB( DB_MASTER );
1583
1584                 $encodedExpiry = Block::encodeExpiry( $expiry, $dbw );
1585
1586                 $expiry_description = '';
1587                 if ( $encodedExpiry != 'infinity' ) {
1588                         $expiry_description = ' (' . wfMsgForContent( 'protect-expiring', $wgContLang->timeanddate( $expiry ),
1589                                 $wgContLang->date( $expiry ) , $wgContLang->time( $expiry ) ) . ')';
1590                 }
1591                 else {
1592                         $expiry_description .= ' (' . wfMsgForContent( 'protect-expiry-indefinite' ) . ')';
1593                 }
1594
1595                 # Update protection table
1596                 if ( $create_perm != '' ) {
1597                         $dbw->replace( 'protected_titles', array( array( 'pt_namespace', 'pt_title' ) ),
1598                                 array(
1599                                         'pt_namespace' => $namespace,
1600                                         'pt_title' => $title,
1601                                         'pt_create_perm' => $create_perm,
1602                                         'pt_timestamp' => Block::encodeExpiry( wfTimestampNow(), $dbw ),
1603                                         'pt_expiry' => $encodedExpiry,
1604                                         'pt_user' => $wgUser->getId(),
1605                                         'pt_reason' => $reason,
1606                                 ), __METHOD__
1607                         );
1608                 } else {
1609                         $dbw->delete( 'protected_titles', array( 'pt_namespace' => $namespace,
1610                                 'pt_title' => $title ), __METHOD__ );
1611                 }
1612                 # Update the protection log
1613                 if ( $dbw->affectedRows() ) {
1614                         $log = new LogPage( 'protect' );
1615
1616                         if ( $create_perm ) {
1617                                 $params = array( "[create=$create_perm] $expiry_description", '' );
1618                                 $log->addEntry( ( isset( $this->mRestrictions['create'] ) && $this->mRestrictions['create'] ) ? 'modify' : 'protect', $this, trim( $reason ), $params );
1619                         } else {
1620                                 $log->addEntry( 'unprotect', $this, $reason );
1621                         }
1622                 }
1623
1624                 return true;
1625         }
1626
1627         /**
1628          * Remove any title protection due to page existing
1629          */
1630         public function deleteTitleProtection() {
1631                 $dbw = wfGetDB( DB_MASTER );
1632
1633                 $dbw->delete( 'protected_titles',
1634                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
1635                         __METHOD__ );
1636         }
1637
1638         /**
1639          * Would anybody with sufficient privileges be able to move this page?
1640          * Some pages just aren't movable.
1641          *
1642          * @return \type{\bool} TRUE or FALSE
1643          */
1644         public function isMovable() {
1645                 return MWNamespace::isMovable( $this->getNamespace() ) && $this->getInterwiki() == '';
1646         }
1647
1648         /**
1649          * Can $wgUser read this page?
1650          *
1651          * @return \type{\bool}
1652          * @todo fold these checks into userCan()
1653          */
1654         public function userCanRead() {
1655                 global $wgUser, $wgGroupPermissions;
1656
1657                 static $useShortcut = null;
1658
1659                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
1660                 if ( is_null( $useShortcut ) ) {
1661                         global $wgRevokePermissions;
1662                         $useShortcut = true;
1663                         if ( empty( $wgGroupPermissions['*']['read'] ) ) {
1664                                 # Not a public wiki, so no shortcut
1665                                 $useShortcut = false;
1666                         } elseif ( !empty( $wgRevokePermissions ) ) {
1667                                 /*
1668                                  * Iterate through each group with permissions being revoked (key not included since we don't care
1669                                  * what the group name is), then check if the read permission is being revoked. If it is, then
1670                                  * we don't use the shortcut below since the user might not be able to read, even though anon
1671                                  * reading is allowed.
1672                                  */
1673                                 foreach ( $wgRevokePermissions as $perms ) {
1674                                         if ( !empty( $perms['read'] ) ) {
1675                                                 # We might be removing the read right from the user, so no shortcut
1676                                                 $useShortcut = false;
1677                                                 break;
1678                                         }
1679                                 }
1680                         }
1681                 }
1682
1683                 $result = null;
1684                 wfRunHooks( 'userCan', array( &$this, &$wgUser, 'read', &$result ) );
1685                 if ( $result !== null ) {
1686                         return $result;
1687                 }
1688
1689                 # Shortcut for public wikis, allows skipping quite a bit of code
1690                 if ( $useShortcut )
1691                         return true;
1692
1693                 if ( $wgUser->isAllowed( 'read' ) ) {
1694                         return true;
1695                 } else {
1696                         global $wgWhitelistRead;
1697
1698                         /**
1699                          * Always grant access to the login page.
1700                          * Even anons need to be able to log in.
1701                         */
1702                         if ( $this->isSpecial( 'Userlogin' ) || $this->isSpecial( 'Resetpass' ) ) {
1703                                 return true;
1704                         }
1705
1706                         /**
1707                          * Bail out if there isn't whitelist
1708                          */
1709                         if ( !is_array( $wgWhitelistRead ) ) {
1710                                 return false;
1711                         }
1712
1713                         /**
1714                          * Check for explicit whitelisting
1715                          */
1716                         $name = $this->getPrefixedText();
1717                         $dbName = $this->getPrefixedDBKey();
1718                         // Check with and without underscores
1719                         if ( in_array( $name, $wgWhitelistRead, true ) || in_array( $dbName, $wgWhitelistRead, true ) )
1720                                 return true;
1721
1722                         /**
1723                          * Old settings might have the title prefixed with
1724                          * a colon for main-namespace pages
1725                          */
1726                         if ( $this->getNamespace() == NS_MAIN ) {
1727                                 if ( in_array( ':' . $name, $wgWhitelistRead ) )
1728                                         return true;
1729                         }
1730
1731                         /**
1732                          * If it's a special page, ditch the subpage bit
1733                          * and check again
1734                          */
1735                         if ( $this->getNamespace() == NS_SPECIAL ) {
1736                                 $name = $this->getDBkey();
1737                                 list( $name, /* $subpage */ ) = SpecialPage::resolveAliasWithSubpage( $name );
1738                                 if ( $name === false ) {
1739                                         # Invalid special page, but we show standard login required message
1740                                         return false;
1741                                 }
1742
1743                                 $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
1744                                 if ( in_array( $pure, $wgWhitelistRead, true ) )
1745                                         return true;
1746                         }
1747
1748                 }
1749                 return false;
1750         }
1751
1752         /**
1753          * Is this a talk page of some sort?
1754          *
1755          * @return \type{\bool}
1756          */
1757         public function isTalkPage() {
1758                 return MWNamespace::isTalk( $this->getNamespace() );
1759         }
1760
1761         /**
1762          * Is this a subpage?
1763          *
1764          * @return \type{\bool}
1765          */
1766         public function isSubpage() {
1767                 return MWNamespace::hasSubpages( $this->mNamespace )
1768                         ? strpos( $this->getText(), '/' ) !== false
1769                         : false;
1770         }
1771
1772         /**
1773          * Does this have subpages?  (Warning, usually requires an extra DB query.)
1774          *
1775          * @return \type{\bool}
1776          */
1777         public function hasSubpages() {
1778                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1779                         # Duh
1780                         return false;
1781                 }
1782
1783                 # We dynamically add a member variable for the purpose of this method
1784                 # alone to cache the result.  There's no point in having it hanging
1785                 # around uninitialized in every Title object; therefore we only add it
1786                 # if needed and don't declare it statically.
1787                 if ( isset( $this->mHasSubpages ) ) {
1788                         return $this->mHasSubpages;
1789                 }
1790
1791                 $subpages = $this->getSubpages( 1 );
1792                 if ( $subpages instanceof TitleArray )
1793                         return $this->mHasSubpages = (bool)$subpages->count();
1794                 return $this->mHasSubpages = false;
1795         }
1796
1797         /**
1798          * Get all subpages of this page.
1799          *
1800          * @param $limit Maximum number of subpages to fetch; -1 for no limit
1801          * @return mixed TitleArray, or empty array if this page's namespace
1802          *  doesn't allow subpages
1803          */
1804         public function getSubpages( $limit = -1 ) {
1805                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) )
1806                         return array();
1807
1808                 $dbr = wfGetDB( DB_SLAVE );
1809                 $conds['page_namespace'] = $this->getNamespace();
1810                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
1811                 $options = array();
1812                 if ( $limit > -1 )
1813                         $options['LIMIT'] = $limit;
1814                 return $this->mSubpages = TitleArray::newFromResult(
1815                         $dbr->select( 'page',
1816                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
1817                                 $conds,
1818                                 __METHOD__,
1819                                 $options
1820                         )
1821                 );
1822         }
1823
1824         /**
1825          * Could this page contain custom CSS or JavaScript, based
1826          * on the title?
1827          *
1828          * @return \type{\bool}
1829          */
1830         public function isCssOrJsPage() {
1831                 return $this->mNamespace == NS_MEDIAWIKI
1832                         && preg_match( '!\.(?:css|js)$!u', $this->mTextform ) > 0;
1833         }
1834
1835         /**
1836          * Is this a .css or .js subpage of a user page?
1837          * @return \type{\bool}
1838          */
1839         public function isCssJsSubpage() {
1840                 return ( NS_USER == $this->mNamespace and preg_match( "/\\/.*\\.(?:css|js)$/", $this->mTextform ) );
1841         }
1842
1843         /**
1844          * Is this a *valid* .css or .js subpage of a user page?
1845          * Check that the corresponding skin exists
1846          *
1847          * @return \type{\bool}
1848          */
1849         public function isValidCssJsSubpage() {
1850                 if ( $this->isCssJsSubpage() ) {
1851                         $name = $this->getSkinFromCssJsSubpage();
1852                         if ( $name == 'common' ) return true;
1853                         $skinNames = Skin::getSkinNames();
1854                         return array_key_exists( $name, $skinNames );
1855                 } else {
1856                         return false;
1857                 }
1858         }
1859
1860         /**
1861          * Trim down a .css or .js subpage title to get the corresponding skin name
1862          *
1863          * @return string containing skin name from .css or .js subpage title
1864          */
1865         public function getSkinFromCssJsSubpage() {
1866                 $subpage = explode( '/', $this->mTextform );
1867                 $subpage = $subpage[ count( $subpage ) - 1 ];
1868                 return( str_replace( array( '.css', '.js' ), array( '', '' ), $subpage ) );
1869         }
1870
1871         /**
1872          * Is this a .css subpage of a user page?
1873          *
1874          * @return \type{\bool}
1875          */
1876         public function isCssSubpage() {
1877                 return ( NS_USER == $this->mNamespace && preg_match( "/\\/.*\\.css$/", $this->mTextform ) );
1878         }
1879
1880         /**
1881          * Is this a .js subpage of a user page?
1882          *
1883          * @return \type{\bool}
1884          */
1885         public function isJsSubpage() {
1886                 return ( NS_USER == $this->mNamespace && preg_match( "/\\/.*\\.js$/", $this->mTextform ) );
1887         }
1888
1889         /**
1890          * Protect css subpages of user pages: can $wgUser edit
1891          * this page?
1892          *
1893          * @return \type{\bool}
1894          * @todo XXX: this might be better using restrictions
1895          */
1896         public function userCanEditCssSubpage() {
1897                 global $wgUser;
1898                 return ( ( $wgUser->isAllowed( 'editusercssjs' ) && $wgUser->isAllowed( 'editusercss' ) )
1899                         || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
1900         }
1901         /**
1902          * Protect js subpages of user pages: can $wgUser edit
1903          * this page?
1904          *
1905          * @return \type{\bool}
1906          * @todo XXX: this might be better using restrictions
1907          */
1908         public function userCanEditJsSubpage() {
1909                 global $wgUser;
1910                 return ( ( $wgUser->isAllowed( 'editusercssjs' ) && $wgUser->isAllowed( 'edituserjs' ) )
1911                        || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
1912         }
1913
1914         /**
1915          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
1916          *
1917          * @return \type{\bool} If the page is subject to cascading restrictions.
1918          */
1919         public function isCascadeProtected() {
1920                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
1921                 return ( $sources > 0 );
1922         }
1923
1924         /**
1925          * Cascading protection: Get the source of any cascading restrictions on this page.
1926          *
1927          * @param $getPages \type{\bool} Whether or not to retrieve the actual pages
1928          *        that the restrictions have come from.
1929          * @return \type{\arrayof{mixed title array, restriction array}} Array of the Title
1930          *         objects of the pages from which cascading restrictions have come,
1931          *         false for none, or true if such restrictions exist, but $getPages was not set.
1932          *         The restriction array is an array of each type, each of which contains a
1933          *         array of unique groups.
1934          */
1935         public function getCascadeProtectionSources( $getPages = true ) {
1936                 $pagerestrictions = array();
1937
1938                 if ( isset( $this->mCascadeSources ) && $getPages ) {
1939                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
1940                 } else if ( isset( $this->mHasCascadingRestrictions ) && !$getPages ) {
1941                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
1942                 }
1943
1944                 wfProfileIn( __METHOD__ );
1945
1946                 $dbr = wfGetDB( DB_SLAVE );
1947
1948                 if ( $this->getNamespace() == NS_FILE ) {
1949                         $tables = array ( 'imagelinks', 'page_restrictions' );
1950                         $where_clauses = array(
1951                                 'il_to' => $this->getDBkey(),
1952                                 'il_from=pr_page',
1953                                 'pr_cascade' => 1 );
1954                 } else {
1955                         $tables = array ( 'templatelinks', 'page_restrictions' );
1956                         $where_clauses = array(
1957                                 'tl_namespace' => $this->getNamespace(),
1958                                 'tl_title' => $this->getDBkey(),
1959                                 'tl_from=pr_page',
1960                                 'pr_cascade' => 1 );
1961                 }
1962
1963                 if ( $getPages ) {
1964                         $cols = array( 'pr_page', 'page_namespace', 'page_title',
1965                                                    'pr_expiry', 'pr_type', 'pr_level' );
1966                         $where_clauses[] = 'page_id=pr_page';
1967                         $tables[] = 'page';
1968                 } else {
1969                         $cols = array( 'pr_expiry' );
1970                 }
1971
1972                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
1973
1974                 $sources = $getPages ? array() : false;
1975                 $now = wfTimestampNow();
1976                 $purgeExpired = false;
1977
1978                 foreach ( $res as $row ) {
1979                         $expiry = Block::decodeExpiry( $row->pr_expiry );
1980                         if ( $expiry > $now ) {
1981                                 if ( $getPages ) {
1982                                         $page_id = $row->pr_page;
1983                                         $page_ns = $row->page_namespace;
1984                                         $page_title = $row->page_title;
1985                                         $sources[$page_id] = Title::makeTitle( $page_ns, $page_title );
1986                                         # Add groups needed for each restriction type if its not already there
1987                                         # Make sure this restriction type still exists
1988
1989                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
1990                                                 $pagerestrictions[$row->pr_type] = array();
1991                                         }
1992
1993                                         if ( isset( $pagerestrictions[$row->pr_type] ) &&
1994                                                  !in_array( $row->pr_level, $pagerestrictions[$row->pr_type] ) ) {
1995                                                 $pagerestrictions[$row->pr_type][] = $row->pr_level;
1996                                         }
1997                                 } else {
1998                                         $sources = true;
1999                                 }
2000                         } else {
2001                                 // Trigger lazy purge of expired restrictions from the db
2002                                 $purgeExpired = true;
2003                         }
2004                 }
2005                 if ( $purgeExpired ) {
2006                         Title::purgeExpiredRestrictions();
2007                 }
2008
2009                 wfProfileOut( __METHOD__ );
2010
2011                 if ( $getPages ) {
2012                         $this->mCascadeSources = $sources;
2013                         $this->mCascadingRestrictions = $pagerestrictions;
2014                 } else {
2015                         $this->mHasCascadingRestrictions = $sources;
2016                 }
2017
2018                 return array( $sources, $pagerestrictions );
2019         }
2020
2021         /**
2022          * Returns cascading restrictions for the current article
2023          *
2024          * @return Boolean
2025          */
2026         function areRestrictionsCascading() {
2027                 if ( !$this->mRestrictionsLoaded ) {
2028                         $this->loadRestrictions();
2029                 }
2030
2031                 return $this->mCascadeRestriction;
2032         }
2033
2034         /**
2035          * Loads a string into mRestrictions array
2036          *
2037          * @param $res \type{Resource} restrictions as an SQL result.
2038          * @param $oldFashionedRestrictions string comma-separated list of page
2039          *        restrictions from page table (pre 1.10)
2040          */
2041         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
2042                 $rows = array();
2043                 $dbr = wfGetDB( DB_SLAVE );
2044
2045                 while ( $row = $dbr->fetchObject( $res ) ) {
2046                         $rows[] = $row;
2047                 }
2048
2049                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
2050         }
2051
2052         /**
2053          * Compiles list of active page restrictions from both page table (pre 1.10)
2054          * and page_restrictions table
2055          *
2056          * @param $rows array of db result objects
2057          * @param $oldFashionedRestrictions string comma-separated list of page
2058          *        restrictions from page table (pre 1.10)
2059          */
2060         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
2061                 $dbr = wfGetDB( DB_SLAVE );
2062
2063                 $restrictionTypes = $this->getRestrictionTypes();
2064
2065                 foreach ( $restrictionTypes as $type ) {
2066                         $this->mRestrictions[$type] = array();
2067                         $this->mRestrictionsExpiry[$type] = Block::decodeExpiry( '' );
2068                 }
2069
2070                 $this->mCascadeRestriction = false;
2071
2072                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2073
2074                 if ( $oldFashionedRestrictions === null ) {
2075                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2076                                 array( 'page_id' => $this->getArticleId() ), __METHOD__ );
2077                 }
2078
2079                 if ( $oldFashionedRestrictions != '' ) {
2080
2081                         foreach ( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2082                                 $temp = explode( '=', trim( $restrict ) );
2083                                 if ( count( $temp ) == 1 ) {
2084                                         // old old format should be treated as edit/move restriction
2085                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2086                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2087                                 } else {
2088                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
2089                                 }
2090                         }
2091
2092                         $this->mOldRestrictions = true;
2093
2094                 }
2095
2096                 if ( count( $rows ) ) {
2097                         # Current system - load second to make them override.
2098                         $now = wfTimestampNow();
2099                         $purgeExpired = false;
2100
2101                         foreach ( $rows as $row ) {
2102                                 # Cycle through all the restrictions.
2103
2104                                 // Don't take care of restrictions types that aren't allowed
2105
2106                                 if ( !in_array( $row->pr_type, $restrictionTypes ) )
2107                                         continue;
2108
2109                                 // This code should be refactored, now that it's being used more generally,
2110                                 // But I don't really see any harm in leaving it in Block for now -werdna
2111                                 $expiry = Block::decodeExpiry( $row->pr_expiry );
2112
2113                                 // Only apply the restrictions if they haven't expired!
2114                                 if ( !$expiry || $expiry > $now ) {
2115                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2116                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2117
2118                                         $this->mCascadeRestriction |= $row->pr_cascade;
2119                                 } else {
2120                                         // Trigger a lazy purge of expired restrictions
2121                                         $purgeExpired = true;
2122                                 }
2123                         }
2124
2125                         if ( $purgeExpired ) {
2126                                 Title::purgeExpiredRestrictions();
2127                         }
2128                 }
2129
2130                 $this->mRestrictionsLoaded = true;
2131         }
2132
2133         /**
2134          * Load restrictions from the page_restrictions table
2135          *
2136          * @param $oldFashionedRestrictions string comma-separated list of page
2137          *        restrictions from page table (pre 1.10)
2138          */
2139         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2140                 if ( !$this->mRestrictionsLoaded ) {
2141                         if ( $this->exists() ) {
2142                                 $dbr = wfGetDB( DB_SLAVE );
2143
2144                                 $res = $dbr->select( 'page_restrictions', '*',
2145                                         array ( 'pr_page' => $this->getArticleId() ), __METHOD__ );
2146
2147                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2148                         } else {
2149                                 $title_protection = $this->getTitleProtection();
2150
2151                                 if ( $title_protection ) {
2152                                         $now = wfTimestampNow();
2153                                         $expiry = Block::decodeExpiry( $title_protection['pt_expiry'] );
2154
2155                                         if ( !$expiry || $expiry > $now ) {
2156                                                 // Apply the restrictions
2157                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2158                                                 $this->mRestrictions['create'] = explode( ',', trim( $title_protection['pt_create_perm'] ) );
2159                                         } else { // Get rid of the old restrictions
2160                                                 Title::purgeExpiredRestrictions();
2161                                         }
2162                                 } else {
2163                                         $this->mRestrictionsExpiry['create'] = Block::decodeExpiry( '' );
2164                                 }
2165                                 $this->mRestrictionsLoaded = true;
2166                         }
2167                 }
2168         }
2169
2170         /**
2171          * Purge expired restrictions from the page_restrictions table
2172          */
2173         static function purgeExpiredRestrictions() {
2174                 $dbw = wfGetDB( DB_MASTER );
2175                 $dbw->delete( 'page_restrictions',
2176                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2177                         __METHOD__ );
2178
2179                 $dbw->delete( 'protected_titles',
2180                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2181                         __METHOD__ );
2182         }
2183
2184         /**
2185          * Accessor/initialisation for mRestrictions
2186          *
2187          * @param $action \type{\string} action that permission needs to be checked for
2188          * @return \type{\arrayof{\string}} the array of groups allowed to edit this article
2189          */
2190         public function getRestrictions( $action ) {
2191                 if ( !$this->mRestrictionsLoaded ) {
2192                         $this->loadRestrictions();
2193                 }
2194                 return isset( $this->mRestrictions[$action] )
2195                                 ? $this->mRestrictions[$action]
2196                                 : array();
2197         }
2198
2199         /**
2200          * Get the expiry time for the restriction against a given action
2201          *
2202          * @return 14-char timestamp, or 'infinity' if the page is protected forever
2203          *      or not protected at all, or false if the action is not recognised.
2204          */
2205         public function getRestrictionExpiry( $action ) {
2206                 if ( !$this->mRestrictionsLoaded ) {
2207                         $this->loadRestrictions();
2208                 }
2209                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2210         }
2211
2212         /**
2213          * Is there a version of this page in the deletion archive?
2214          *
2215          * @return \type{\int} the number of archived revisions
2216          */
2217         public function isDeleted() {
2218                 if ( $this->getNamespace() < 0 ) {
2219                         $n = 0;
2220                 } else {
2221                         $dbr = wfGetDB( DB_SLAVE );
2222                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2223                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2224                                 __METHOD__
2225                         );
2226                         if ( $this->getNamespace() == NS_FILE ) {
2227                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2228                                         array( 'fa_name' => $this->getDBkey() ),
2229                                         __METHOD__
2230                                 );
2231                         }
2232                 }
2233                 return (int)$n;
2234         }
2235
2236         /**
2237          * Is there a version of this page in the deletion archive?
2238          *
2239          * @return Boolean
2240          */
2241         public function isDeletedQuick() {
2242                 if ( $this->getNamespace() < 0 ) {
2243                         return false;
2244                 }
2245                 $dbr = wfGetDB( DB_SLAVE );
2246                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2247                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2248                         __METHOD__
2249                 );
2250                 if ( !$deleted && $this->getNamespace() == NS_FILE ) {
2251                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2252                                 array( 'fa_name' => $this->getDBkey() ),
2253                                 __METHOD__
2254                         );
2255                 }
2256                 return $deleted;
2257         }
2258
2259         /**
2260          * Get the article ID for this Title from the link cache,
2261          * adding it if necessary
2262          *
2263          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select
2264          *  for update
2265          * @return \type{\int} the ID
2266          */
2267         public function getArticleID( $flags = 0 ) {
2268                 if ( $this->getNamespace() < 0 ) {
2269                         return $this->mArticleID = 0;
2270                 }
2271                 $linkCache = LinkCache::singleton();
2272                 if ( $flags & GAID_FOR_UPDATE ) {
2273                         $oldUpdate = $linkCache->forUpdate( true );
2274                         $linkCache->clearLink( $this );
2275                         $this->mArticleID = $linkCache->addLinkObj( $this );
2276                         $linkCache->forUpdate( $oldUpdate );
2277                 } else {
2278                         if ( -1 == $this->mArticleID ) {
2279                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2280                         }
2281                 }
2282                 return $this->mArticleID;
2283         }
2284
2285         /**
2286          * Is this an article that is a redirect page?
2287          * Uses link cache, adding it if necessary
2288          *
2289          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select for update
2290          * @return \type{\bool}
2291          */
2292         public function isRedirect( $flags = 0 ) {
2293                 if ( !is_null( $this->mRedirect ) )
2294                         return $this->mRedirect;
2295                 # Calling getArticleID() loads the field from cache as needed
2296                 if ( !$this->getArticleID( $flags ) ) {
2297                         return $this->mRedirect = false;
2298                 }
2299                 $linkCache = LinkCache::singleton();
2300                 $this->mRedirect = (bool)$linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2301
2302                 return $this->mRedirect;
2303         }
2304
2305         /**
2306          * What is the length of this page?
2307          * Uses link cache, adding it if necessary
2308          *
2309          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select for update
2310          * @return \type{\bool}
2311          */
2312         public function getLength( $flags = 0 ) {
2313                 if ( $this->mLength != -1 )
2314                         return $this->mLength;
2315                 # Calling getArticleID() loads the field from cache as needed
2316                 if ( !$this->getArticleID( $flags ) ) {
2317                         return $this->mLength = 0;
2318                 }
2319                 $linkCache = LinkCache::singleton();
2320                 $this->mLength = intval( $linkCache->getGoodLinkFieldObj( $this, 'length' ) );
2321
2322                 return $this->mLength;
2323         }
2324
2325         /**
2326          * What is the page_latest field for this page?
2327          *
2328          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select for update
2329          * @return \type{\int} or false if the page doesn't exist
2330          */
2331         public function getLatestRevID( $flags = 0 ) {
2332                 if ( $this->mLatestID !== false )
2333                         return $this->mLatestID;
2334
2335                 $db = ( $flags & GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
2336                 $this->mLatestID = (int)$db->selectField(
2337                         'page', 'page_latest', $this->pageCond(), __METHOD__ );
2338                 return $this->mLatestID;
2339         }
2340
2341         /**
2342          * This clears some fields in this object, and clears any associated
2343          * keys in the "bad links" section of the link cache.
2344          *
2345          * - This is called from Article::insertNewArticle() to allow
2346          * loading of the new page_id. It's also called from
2347          * Article::doDeleteArticle()
2348          *
2349          * @param $newid \type{\int} the new Article ID
2350          */
2351         public function resetArticleID( $newid ) {
2352                 $linkCache = LinkCache::singleton();
2353                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
2354
2355                 if ( $newid === false ) {
2356                         $this->mArticleID = -1;
2357                 } else {
2358                         $this->mArticleID = intval( $newid );
2359                 }
2360                 $this->mRestrictionsLoaded = false;
2361                 $this->mRestrictions = array();
2362                 $this->mRedirect = null;
2363                 $this->mLength = -1;
2364                 $this->mLatestID = false;
2365         }
2366
2367         /**
2368          * Updates page_touched for this page; called from LinksUpdate.php
2369          *
2370          * @return \type{\bool} true if the update succeded
2371          */
2372         public function invalidateCache() {
2373                 if ( wfReadOnly() ) {
2374                         return;
2375                 }
2376                 $dbw = wfGetDB( DB_MASTER );
2377                 $success = $dbw->update( 'page',
2378                         array( 'page_touched' => $dbw->timestamp() ),
2379                         $this->pageCond(),
2380                         __METHOD__
2381                 );
2382                 HTMLFileCache::clearFileCache( $this );
2383                 return $success;
2384         }
2385
2386         /**
2387          * Prefix some arbitrary text with the namespace or interwiki prefix
2388          * of this object
2389          *
2390          * @param $name \type{\string} the text
2391          * @return \type{\string} the prefixed text
2392          * @private
2393          */
2394         /* private */ function prefix( $name ) {
2395                 $p = '';
2396                 if ( $this->mInterwiki != '' ) {
2397                         $p = $this->mInterwiki . ':';
2398                 }
2399                 if ( 0 != $this->mNamespace ) {
2400                         $p .= $this->getNsText() . ':';
2401                 }
2402                 return $p . $name;
2403         }
2404
2405         /**
2406          * Returns a simple regex that will match on characters and sequences invalid in titles.
2407          * Note that this doesn't pick up many things that could be wrong with titles, but that
2408          * replacing this regex with something valid will make many titles valid.
2409          *
2410          * @return string regex string
2411          */
2412         static function getTitleInvalidRegex() {
2413                 static $rxTc = false;
2414                 if ( !$rxTc ) {
2415                         # Matching titles will be held as illegal.
2416                         $rxTc = '/' .
2417                                 # Any character not allowed is forbidden...
2418                                 '[^' . Title::legalChars() . ']' .
2419                                 # URL percent encoding sequences interfere with the ability
2420                                 # to round-trip titles -- you can't link to them consistently.
2421                                 '|%[0-9A-Fa-f]{2}' .
2422                                 # XML/HTML character references produce similar issues.
2423                                 '|&[A-Za-z0-9\x80-\xff]+;' .
2424                                 '|&#[0-9]+;' .
2425                                 '|&#x[0-9A-Fa-f]+;' .
2426                                 '/S';
2427                 }
2428
2429                 return $rxTc;
2430         }
2431
2432         /**
2433          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
2434          *
2435          * @param $text string containing title to capitalize
2436          * @param $ns int namespace index, defaults to NS_MAIN
2437          * @return String containing capitalized title
2438          */
2439         public static function capitalize( $text, $ns = NS_MAIN ) {
2440                 global $wgContLang;
2441
2442                 if ( MWNamespace::isCapitalized( $ns ) )
2443                         return $wgContLang->ucfirst( $text );
2444                 else
2445                         return $text;
2446         }
2447
2448         /**
2449          * Secure and split - main initialisation function for this object
2450          *
2451          * Assumes that mDbkeyform has been set, and is urldecoded
2452          * and uses underscores, but not otherwise munged.  This function
2453          * removes illegal characters, splits off the interwiki and
2454          * namespace prefixes, sets the other forms, and canonicalizes
2455          * everything.
2456          *
2457          * @return \type{\bool} true on success
2458          */
2459         private function secureAndSplit() {
2460                 global $wgContLang, $wgLocalInterwiki;
2461
2462                 # Initialisation
2463                 $rxTc = self::getTitleInvalidRegex();
2464
2465                 $this->mInterwiki = $this->mFragment = '';
2466                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2467
2468                 $dbkey = $this->mDbkeyform;
2469
2470                 # Strip Unicode bidi override characters.
2471                 # Sometimes they slip into cut-n-pasted page titles, where the
2472                 # override chars get included in list displays.
2473                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
2474
2475                 # Clean up whitespace
2476                 # Note: use of the /u option on preg_replace here will cause
2477                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
2478                 # conveniently disabling them.
2479                 #
2480                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
2481                 $dbkey = trim( $dbkey, '_' );
2482
2483                 if ( $dbkey == '' ) {
2484                         return false;
2485                 }
2486
2487                 if ( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2488                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2489                         return false;
2490                 }
2491
2492                 $this->mDbkeyform = $dbkey;
2493
2494                 # Initial colon indicates main namespace rather than specified default
2495                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
2496                 if ( ':' == $dbkey { 0 } ) {
2497                         $this->mNamespace = NS_MAIN;
2498                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
2499                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
2500                 }
2501
2502                 # Namespace or interwiki prefix
2503                 $firstPass = true;
2504                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
2505                 do {
2506                         $m = array();
2507                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
2508                                 $p = $m[1];
2509                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
2510                                         # Ordinary namespace
2511                                         $dbkey = $m[2];
2512                                         $this->mNamespace = $ns;
2513                                         # For Talk:X pages, check if X has a "namespace" prefix
2514                                         if ( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
2515                                                 if ( $wgContLang->getNsIndex( $x[1] ) )
2516                                                         return false; # Disallow Talk:File:x type titles...
2517                                                 else if ( Interwiki::isValidInterwiki( $x[1] ) )
2518                                                         return false; # Disallow Talk:Interwiki:x type titles...
2519                                         }
2520                                 } elseif ( Interwiki::isValidInterwiki( $p ) ) {
2521                                         if ( !$firstPass ) {
2522                                                 # Can't make a local interwiki link to an interwiki link.
2523                                                 # That's just crazy!
2524                                                 return false;
2525                                         }
2526
2527                                         # Interwiki link
2528                                         $dbkey = $m[2];
2529                                         $this->mInterwiki = $wgContLang->lc( $p );
2530
2531                                         # Redundant interwiki prefix to the local wiki
2532                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
2533                                                 if ( $dbkey == '' ) {
2534                                                         # Can't have an empty self-link
2535                                                         return false;
2536                                                 }
2537                                                 $this->mInterwiki = '';
2538                                                 $firstPass = false;
2539                                                 # Do another namespace split...
2540                                                 continue;
2541                                         }
2542
2543                                         # If there's an initial colon after the interwiki, that also
2544                                         # resets the default namespace
2545                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
2546                                                 $this->mNamespace = NS_MAIN;
2547                                                 $dbkey = substr( $dbkey, 1 );
2548                                         }
2549                                 }
2550                                 # If there's no recognized interwiki or namespace,
2551                                 # then let the colon expression be part of the title.
2552                         }
2553                         break;
2554                 } while ( true );
2555
2556                 # We already know that some pages won't be in the database!
2557                 #
2558                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
2559                         $this->mArticleID = 0;
2560                 }
2561                 $fragment = strstr( $dbkey, '#' );
2562                 if ( false !== $fragment ) {
2563                         $this->setFragment( $fragment );
2564                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
2565                         # remove whitespace again: prevents "Foo_bar_#"
2566                         # becoming "Foo_bar_"
2567                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
2568                 }
2569
2570                 # Reject illegal characters.
2571                 #
2572                 if ( preg_match( $rxTc, $dbkey ) ) {
2573                         return false;
2574                 }
2575
2576                 /**
2577                  * Pages with "/./" or "/../" appearing in the URLs will often be un-
2578                  * reachable due to the way web browsers deal with 'relative' URLs.
2579                  * Also, they conflict with subpage syntax.  Forbid them explicitly.
2580                  */
2581                 if ( strpos( $dbkey, '.' ) !== false &&
2582                      ( $dbkey === '.' || $dbkey === '..' ||
2583                        strpos( $dbkey, './' ) === 0  ||
2584                        strpos( $dbkey, '../' ) === 0 ||
2585                        strpos( $dbkey, '/./' ) !== false ||
2586                        strpos( $dbkey, '/../' ) !== false  ||
2587                        substr( $dbkey, -2 ) == '/.' ||
2588                        substr( $dbkey, -3 ) == '/..' ) )
2589                 {
2590                         return false;
2591                 }
2592
2593                 /**
2594                  * Magic tilde sequences? Nu-uh!
2595                  */
2596                 if ( strpos( $dbkey, '~~~' ) !== false ) {
2597                         return false;
2598                 }
2599
2600                 /**
2601                  * Limit the size of titles to 255 bytes.
2602                  * This is typically the size of the underlying database field.
2603                  * We make an exception for special pages, which don't need to be stored
2604                  * in the database, and may edge over 255 bytes due to subpage syntax
2605                  * for long titles, e.g. [[Special:Block/Long name]]
2606                  */
2607                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
2608                   strlen( $dbkey ) > 512 )
2609                 {
2610                         return false;
2611                 }
2612
2613                 /**
2614                  * Normally, all wiki links are forced to have
2615                  * an initial capital letter so [[foo]] and [[Foo]]
2616                  * point to the same place.
2617                  *
2618                  * Don't force it for interwikis, since the other
2619                  * site might be case-sensitive.
2620                  */
2621                 $this->mUserCaseDBKey = $dbkey;
2622                 if (  $this->mInterwiki == '' ) {
2623                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
2624                 }
2625
2626                 /**
2627                  * Can't make a link to a namespace alone...
2628                  * "empty" local links can only be self-links
2629                  * with a fragment identifier.
2630                  */
2631                 if ( $dbkey == '' &&
2632                         $this->mInterwiki == '' &&
2633                         $this->mNamespace != NS_MAIN ) {
2634                         return false;
2635                 }
2636                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
2637                 // IP names are not allowed for accounts, and can only be referring to
2638                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
2639                 // there are numerous ways to present the same IP. Having sp:contribs scan
2640                 // them all is silly and having some show the edits and others not is
2641                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
2642                 $dbkey = ( $this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK ) ?
2643                         IP::sanitizeIP( $dbkey ) : $dbkey;
2644                 // Any remaining initial :s are illegal.
2645                 if ( $dbkey !== '' && ':' == $dbkey { 0 } ) {
2646                         return false;
2647                 }
2648
2649                 # Fill fields
2650                 $this->mDbkeyform = $dbkey;
2651                 $this->mUrlform = wfUrlencode( $dbkey );
2652
2653                 $this->mTextform = str_replace( '_', ' ', $dbkey );
2654
2655                 return true;
2656         }
2657
2658         /**
2659          * Set the fragment for this title. Removes the first character from the
2660          * specified fragment before setting, so it assumes you're passing it with
2661          * an initial "#".
2662          *
2663          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
2664          * Still in active use privately.
2665          *
2666          * @param $fragment \type{\string} text
2667          */
2668         public function setFragment( $fragment ) {
2669                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
2670         }
2671
2672         /**
2673          * Get a Title object associated with the talk page of this article
2674          *
2675          * @return \type{Title} the object for the talk page
2676          */
2677         public function getTalkPage() {
2678                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
2679         }
2680
2681         /**
2682          * Get a title object associated with the subject page of this
2683          * talk page
2684          *
2685          * @return \type{Title} the object for the subject page
2686          */
2687         public function getSubjectPage() {
2688                 // Is this the same title?
2689                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
2690                 if ( $this->getNamespace() == $subjectNS ) {
2691                         return $this;
2692                 }
2693                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
2694         }
2695
2696         /**
2697          * Get an array of Title objects linking to this Title
2698          * Also stores the IDs in the link cache.
2699          *
2700          * WARNING: do not use this function on arbitrary user-supplied titles!
2701          * On heavily-used templates it will max out the memory.
2702          *
2703          * @param $options Array: may be FOR UPDATE
2704          * @param $table String: table name
2705          * @param $prefix String: fields prefix
2706          * @return \type{\arrayof{Title}} the Title objects linking here
2707          */
2708         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
2709                 $linkCache = LinkCache::singleton();
2710
2711                 if ( count( $options ) > 0 ) {
2712                         $db = wfGetDB( DB_MASTER );
2713                 } else {
2714                         $db = wfGetDB( DB_SLAVE );
2715                 }
2716
2717                 $res = $db->select( array( 'page', $table ),
2718                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect' ),
2719                         array(
2720                                 "{$prefix}_from=page_id",
2721                                 "{$prefix}_namespace" => $this->getNamespace(),
2722                                 "{$prefix}_title"     => $this->getDBkey() ),
2723                         __METHOD__,
2724                         $options );
2725
2726                 $retVal = array();
2727                 if ( $db->numRows( $res ) ) {
2728                         foreach ( $res as $row ) {
2729                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
2730                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj, $row->page_len, $row->page_is_redirect );
2731                                         $retVal[] = $titleObj;
2732                                 }
2733                         }
2734                 }
2735                 $db->freeResult( $res );
2736                 return $retVal;
2737         }
2738
2739         /**
2740          * Get an array of Title objects using this Title as a template
2741          * Also stores the IDs in the link cache.
2742          *
2743          * WARNING: do not use this function on arbitrary user-supplied titles!
2744          * On heavily-used templates it will max out the memory.
2745          *
2746          * @param $options Array: may be FOR UPDATE
2747          * @return \type{\arrayof{Title}} the Title objects linking here
2748          */
2749         public function getTemplateLinksTo( $options = array() ) {
2750                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
2751         }
2752
2753         /**
2754          * Get an array of Title objects referring to non-existent articles linked from this page
2755          *
2756          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
2757          * @return \type{\arrayof{Title}} the Title objects
2758          */
2759         public function getBrokenLinksFrom() {
2760                 if ( $this->getArticleId() == 0 ) {
2761                         # All links from article ID 0 are false positives
2762                         return array();
2763                 }
2764
2765                 $dbr = wfGetDB( DB_SLAVE );
2766                 $res = $dbr->select(
2767                         array( 'page', 'pagelinks' ),
2768                         array( 'pl_namespace', 'pl_title' ),
2769                         array(
2770                                 'pl_from' => $this->getArticleId(),
2771                                 'page_namespace IS NULL'
2772                         ),
2773                         __METHOD__, array(),
2774                         array(
2775                                 'page' => array(
2776                                         'LEFT JOIN',
2777                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
2778                                 )
2779                         )
2780                 );
2781
2782                 $retVal = array();
2783                 foreach ( $res as $row ) {
2784                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
2785                 }
2786                 return $retVal;
2787         }
2788
2789
2790         /**
2791          * Get a list of URLs to purge from the Squid cache when this
2792          * page changes
2793          *
2794          * @return \type{\arrayof{\string}} the URLs
2795          */
2796         public function getSquidURLs() {
2797                 global $wgContLang;
2798
2799                 $urls = array(
2800                         $this->getInternalURL(),
2801                         $this->getInternalURL( 'action=history' )
2802                 );
2803
2804                 // purge variant urls as well
2805                 if ( $wgContLang->hasVariants() ) {
2806                         $variants = $wgContLang->getVariants();
2807                         foreach ( $variants as $vCode ) {
2808                                 if ( $vCode == $wgContLang->getCode() ) continue; // we don't want default variant
2809                                 $urls[] = $this->getInternalURL( '', $vCode );
2810                         }
2811                 }
2812
2813                 return $urls;
2814         }
2815
2816         /**
2817          * Purge all applicable Squid URLs
2818          */
2819         public function purgeSquid() {
2820                 global $wgUseSquid;
2821                 if ( $wgUseSquid ) {
2822                         $urls = $this->getSquidURLs();
2823                         $u = new SquidUpdate( $urls );
2824                         $u->doUpdate();
2825                 }
2826         }
2827
2828         /**
2829          * Move this page without authentication
2830          *
2831          * @param $nt \type{Title} the new page Title
2832          * @return \type{\mixed} true on success, getUserPermissionsErrors()-like array on failure
2833          */
2834         public function moveNoAuth( &$nt ) {
2835                 return $this->moveTo( $nt, false );
2836         }
2837
2838         /**
2839          * Check whether a given move operation would be valid.
2840          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
2841          *
2842          * @param $nt \type{Title} the new title
2843          * @param $auth \type{\bool} indicates whether $wgUser's permissions
2844          *  should be checked
2845          * @param $reason \type{\string} is the log summary of the move, used for spam checking
2846          * @return \type{\mixed} True on success, getUserPermissionsErrors()-like array on failure
2847          */
2848         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
2849                 global $wgUser;
2850
2851                 $errors = array();
2852                 if ( !$nt ) {
2853                         // Normally we'd add this to $errors, but we'll get
2854                         // lots of syntax errors if $nt is not an object
2855                         return array( array( 'badtitletext' ) );
2856                 }
2857                 if ( $this->equals( $nt ) ) {
2858                         $errors[] = array( 'selfmove' );
2859                 }
2860                 if ( !$this->isMovable() ) {
2861                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
2862                 }
2863                 if ( $nt->getInterwiki() != '' ) {
2864                         $errors[] = array( 'immobile-target-namespace-iw' );
2865                 }
2866                 if ( !$nt->isMovable() ) {
2867                         $errors[] = array( 'immobile-target-namespace', $nt->getNsText() );
2868                 }
2869
2870                 $oldid = $this->getArticleID();
2871                 $newid = $nt->getArticleID();
2872
2873                 if ( strlen( $nt->getDBkey() ) < 1 ) {
2874                         $errors[] = array( 'articleexists' );
2875                 }
2876                 if ( ( $this->getDBkey() == '' ) ||
2877                          ( !$oldid ) ||
2878                      ( $nt->getDBkey() == '' ) ) {
2879                         $errors[] = array( 'badarticleerror' );
2880                 }
2881
2882                 // Image-specific checks
2883                 if ( $this->getNamespace() == NS_FILE ) {
2884                         $file = wfLocalFile( $this );
2885                         if ( $file->exists() ) {
2886                                 if ( $nt->getNamespace() != NS_FILE ) {
2887                                         $errors[] = array( 'imagenocrossnamespace' );
2888                                 }
2889                                 if ( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
2890                                         $errors[] = array( 'imageinvalidfilename' );
2891                                 }
2892                                 if ( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
2893                                         $errors[] = array( 'imagetypemismatch' );
2894                                 }
2895                         }
2896                         $destfile = wfLocalFile( $nt );
2897                         if ( !$wgUser->isAllowed( 'reupload-shared' ) && !$destfile->exists() && wfFindFile( $nt ) ) {
2898                                 $errors[] = array( 'file-exists-sharedrepo' );
2899                         }
2900
2901                 }
2902
2903                 if ( $auth ) {
2904                         $errors = wfMergeErrorArrays( $errors,
2905                                 $this->getUserPermissionsErrors( 'move', $wgUser ),
2906                                 $this->getUserPermissionsErrors( 'edit', $wgUser ),
2907                                 $nt->getUserPermissionsErrors( 'move-target', $wgUser ),
2908                                 $nt->getUserPermissionsErrors( 'edit', $wgUser ) );
2909                 }
2910
2911                 $match = EditPage::matchSummarySpamRegex( $reason );
2912                 if ( $match !== false ) {
2913                         // This is kind of lame, won't display nice
2914                         $errors[] = array( 'spamprotectiontext' );
2915                 }
2916
2917                 $err = null;
2918                 if ( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
2919                         $errors[] = array( 'hookaborted', $err );
2920                 }
2921
2922                 # The move is allowed only if (1) the target doesn't exist, or
2923                 # (2) the target is a redirect to the source, and has no history
2924                 # (so we can undo bad moves right after they're done).
2925
2926                 if ( 0 != $newid ) { # Target exists; check for validity
2927                         if ( ! $this->isValidMoveTarget( $nt ) ) {
2928                                 $errors[] = array( 'articleexists' );
2929                         }
2930                 } else {
2931                         $tp = $nt->getTitleProtection();
2932                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
2933                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
2934                                 $errors[] = array( 'cantmove-titleprotected' );
2935                         }
2936                 }
2937                 if ( empty( $errors ) )
2938                         return true;
2939                 return $errors;
2940         }
2941
2942         /**
2943          * Move a title to a new location
2944          *
2945          * @param $nt \type{Title} the new title
2946          * @param $auth \type{\bool} indicates whether $wgUser's permissions
2947          *  should be checked
2948          * @param $reason \type{\string} The reason for the move
2949          * @param $createRedirect \type{\bool} Whether to create a redirect from the old title to the new title.
2950          *  Ignored if the user doesn't have the suppressredirect right.
2951          * @return \type{\mixed} true on success, getUserPermissionsErrors()-like array on failure
2952          */
2953         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
2954                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
2955                 if ( is_array( $err ) ) {
2956                         return $err;
2957                 }
2958
2959                 // If it is a file, move it first. It is done before all other moving stuff is done because it's hard to revert
2960                 $dbw = wfGetDB( DB_MASTER );
2961                 if ( $this->getNamespace() == NS_FILE ) {
2962                         $file = wfLocalFile( $this );
2963                         if ( $file->exists() ) {
2964                                 $status = $file->move( $nt );
2965                                 if ( !$status->isOk() ) {
2966                                         return $status->getErrorsArray();
2967                                 }
2968                         }
2969                 }
2970
2971                 $pageid = $this->getArticleID();
2972                 $protected = $this->isProtected();
2973                 if ( $nt->exists() ) {
2974                         $err = $this->moveOverExistingRedirect( $nt, $reason, $createRedirect );
2975                         $pageCountChange = ( $createRedirect ? 0 : -1 );
2976                 } else { # Target didn't exist, do normal move.
2977                         $err = $this->moveToNewTitle( $nt, $reason, $createRedirect );
2978                         $pageCountChange = ( $createRedirect ? 1 : 0 );
2979                 }
2980
2981                 if ( is_array( $err ) ) {
2982                         return $err;
2983                 }
2984                 $redirid = $this->getArticleID();
2985
2986                 // Category memberships include a sort key which may be customized.
2987                 // If it's left as the default (the page title), we need to update
2988                 // the sort key to match the new title.
2989                 //
2990                 // Be careful to avoid resetting cl_timestamp, which may disturb
2991                 // time-based lists on some sites.
2992                 //
2993                 // Warning -- if the sort key is *explicitly* set to the old title,
2994                 // we can't actually distinguish it from a default here, and it'll
2995                 // be set to the new title even though it really shouldn't.
2996                 // It'll get corrected on the next edit, but resetting cl_timestamp.
2997                 $dbw->update( 'categorylinks',
2998                         array(
2999                                 'cl_sortkey' => $nt->getPrefixedText(),
3000                                 'cl_timestamp=cl_timestamp' ),
3001                         array(
3002                                 'cl_from' => $pageid,
3003                                 'cl_sortkey' => $this->getPrefixedText() ),
3004                         __METHOD__ );
3005
3006                 if ( $protected ) {
3007                         # Protect the redirect title as the title used to be...
3008                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
3009                                 array(
3010                                         'pr_page'    => $redirid,
3011                                         'pr_type'    => 'pr_type',
3012                                         'pr_level'   => 'pr_level',
3013                                         'pr_cascade' => 'pr_cascade',
3014                                         'pr_user'    => 'pr_user',
3015                                         'pr_expiry'  => 'pr_expiry'
3016                                 ),
3017                                 array( 'pr_page' => $pageid ),
3018                                 __METHOD__,
3019                                 array( 'IGNORE' )
3020                         );
3021                         # Update the protection log
3022                         $log = new LogPage( 'protect' );
3023                         $comment = wfMsgForContent( 'prot_1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
3024                         if ( $reason ) $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3025                         $log->addEntry( 'move_prot', $nt, $comment, array( $this->getPrefixedText() ) ); // FIXME: $params?
3026                 }
3027
3028                 # Update watchlists
3029                 $oldnamespace = $this->getNamespace() & ~1;
3030                 $newnamespace = $nt->getNamespace() & ~1;
3031                 $oldtitle = $this->getDBkey();
3032                 $newtitle = $nt->getDBkey();
3033
3034                 if ( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
3035                         WatchedItem::duplicateEntries( $this, $nt );
3036                 }
3037
3038                 # Update search engine
3039                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
3040                 $u->doUpdate();
3041                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
3042                 $u->doUpdate();
3043
3044                 # Update site_stats
3045                 if ( $this->isContentPage() && !$nt->isContentPage() ) {
3046                         # No longer a content page
3047                         # Not viewed, edited, removing
3048                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange );
3049                 } elseif ( !$this->isContentPage() && $nt->isContentPage() ) {
3050                         # Now a content page
3051                         # Not viewed, edited, adding
3052                         $u = new SiteStatsUpdate( 0, 1, + 1, $pageCountChange );
3053                 } elseif ( $pageCountChange ) {
3054                         # Redirect added
3055                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
3056                 } else {
3057                         # Nothing special
3058                         $u = false;
3059                 }
3060                 if ( $u )
3061                         $u->doUpdate();
3062                 # Update message cache for interface messages
3063                 if ( $nt->getNamespace() == NS_MEDIAWIKI ) {
3064                         global $wgMessageCache;
3065
3066                         # @bug 17860: old article can be deleted, if this the case,
3067                         # delete it from message cache
3068                         if ( $this->getArticleID() === 0 ) {
3069                                 $wgMessageCache->replace( $this->getDBkey(), false );
3070                         } else {
3071                                 $oldarticle = new Article( $this );
3072                                 $wgMessageCache->replace( $this->getDBkey(), $oldarticle->getContent() );
3073                         }
3074
3075                         $newarticle = new Article( $nt );
3076                         $wgMessageCache->replace( $nt->getDBkey(), $newarticle->getContent() );
3077                 }
3078
3079                 global $wgUser;
3080                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3081                 return true;
3082         }
3083
3084         /**
3085          * Move page to a title which is at present a redirect to the
3086          * source page
3087          *
3088          * @param $nt \type{Title} the page to move to, which should currently
3089          *  be a redirect
3090          * @param $reason \type{\string} The reason for the move
3091          * @param $createRedirect \type{\bool} Whether to leave a redirect at the old title.
3092          *  Ignored if the user doesn't have the suppressredirect right
3093          */
3094         private function moveOverExistingRedirect( &$nt, $reason = '', $createRedirect = true ) {
3095                 global $wgUseSquid, $wgUser, $wgContLang;
3096
3097                 $comment = wfMsgForContent( '1movedto2_redir', $this->getPrefixedText(), $nt->getPrefixedText() );
3098
3099                 if ( $reason ) {
3100                         $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3101                 }
3102                 # Truncate for whole multibyte characters. +5 bytes for ellipsis
3103                 $comment = $wgContLang->truncate( $comment, 250 );
3104
3105                 $now = wfTimestampNow();
3106                 $newid = $nt->getArticleID();
3107                 $oldid = $this->getArticleID();
3108                 $latest = $this->getLatestRevID();
3109
3110                 $dbw = wfGetDB( DB_MASTER );
3111
3112                 $rcts = $dbw->timestamp( $nt->getEarliestRevTime() );
3113                 $newns = $nt->getNamespace();
3114                 $newdbk = $nt->getDBkey();
3115
3116                 # Delete the old redirect. We don't save it to history since
3117                 # by definition if we've got here it's rather uninteresting.
3118                 # We have to remove it so that the next step doesn't trigger
3119                 # a conflict on the unique namespace+title index...
3120                 $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3121                 if ( !$dbw->cascadingDeletes() ) {
3122                         $dbw->delete( 'revision', array( 'rev_page' => $newid ), __METHOD__ );
3123                         global $wgUseTrackbacks;
3124                         if ( $wgUseTrackbacks )
3125                                 $dbw->delete( 'trackbacks', array( 'tb_page' => $newid ), __METHOD__ );
3126                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
3127                         $dbw->delete( 'imagelinks', array( 'il_from' => $newid ), __METHOD__ );
3128                         $dbw->delete( 'categorylinks', array( 'cl_from' => $newid ), __METHOD__ );
3129                         $dbw->delete( 'templatelinks', array( 'tl_from' => $newid ), __METHOD__ );
3130                         $dbw->delete( 'externallinks', array( 'el_from' => $newid ), __METHOD__ );
3131                         $dbw->delete( 'langlinks', array( 'll_from' => $newid ), __METHOD__ );
3132                         $dbw->delete( 'redirect', array( 'rd_from' => $newid ), __METHOD__ );
3133                 }
3134                 // If the redirect was recently created, it may have an entry in recentchanges still
3135                 $dbw->delete( 'recentchanges',
3136                         array( 'rc_timestamp' => $rcts, 'rc_namespace' => $newns, 'rc_title' => $newdbk, 'rc_new' => 1 ),
3137                         __METHOD__
3138                 );
3139
3140                 # Save a null revision in the page's history notifying of the move
3141                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3142                 $nullRevId = $nullRevision->insertOn( $dbw );
3143
3144                 $article = new Article( $this );
3145                 wfRunHooks( 'NewRevisionFromEditComplete', array( $article, $nullRevision, $latest, $wgUser ) );
3146
3147                 # Change the name of the target page:
3148                 $dbw->update( 'page',
3149                         /* SET */ array(
3150                                 'page_touched'   => $dbw->timestamp( $now ),
3151                                 'page_namespace' => $nt->getNamespace(),
3152                                 'page_title'     => $nt->getDBkey(),
3153                                 'page_latest'    => $nullRevId,
3154                         ),
3155                         /* WHERE */ array( 'page_id' => $oldid ),
3156                         __METHOD__
3157                 );
3158                 $nt->resetArticleID( $oldid );
3159
3160                 # Recreate the redirect, this time in the other direction.
3161                 if ( $createRedirect || !$wgUser->isAllowed( 'suppressredirect' ) ) {
3162                         $mwRedir = MagicWord::get( 'redirect' );
3163                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3164                         $redirectArticle = new Article( $this );
3165                         $newid = $redirectArticle->insertOn( $dbw );
3166                         $redirectRevision = new Revision( array(
3167                                 'page'    => $newid,
3168                                 'comment' => $comment,
3169                                 'text'    => $redirectText ) );
3170                         $redirectRevision->insertOn( $dbw );
3171                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3172
3173                         wfRunHooks( 'NewRevisionFromEditComplete', array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3174
3175                         # Now, we record the link from the redirect to the new title.
3176                         # It should have no other outgoing links...
3177                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
3178                         $dbw->insert( 'pagelinks',
3179                                 array(
3180                                         'pl_from'      => $newid,
3181                                         'pl_namespace' => $nt->getNamespace(),
3182                                         'pl_title'     => $nt->getDBkey() ),
3183                                 __METHOD__ );
3184                         $redirectSuppressed = false;
3185                 } else {
3186                         $this->resetArticleID( 0 );
3187                         $redirectSuppressed = true;
3188                 }
3189
3190                 # Log the move
3191                 $log = new LogPage( 'move' );
3192                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText(), 2 => $redirectSuppressed ) );
3193
3194                 # Purge squid
3195                 if ( $wgUseSquid ) {
3196                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
3197                         $u = new SquidUpdate( $urls );
3198                         $u->doUpdate();
3199                 }
3200
3201         }
3202
3203         /**
3204          * Move page to non-existing title.
3205          *
3206          * @param $nt \type{Title} the new Title
3207          * @param $reason \type{\string} The reason for the move
3208          * @param $createRedirect \type{\bool} Whether to create a redirect from the old title to the new title
3209          *  Ignored if the user doesn't have the suppressredirect right
3210          */
3211         private function moveToNewTitle( &$nt, $reason = '', $createRedirect = true ) {
3212                 global $wgUseSquid, $wgUser, $wgContLang;
3213
3214                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
3215                 if ( $reason ) {
3216                         $comment .= wfMsgExt( 'colon-separator',
3217                                 array( 'escapenoentities', 'content' ) );
3218                         $comment .= $reason;
3219                 }
3220                 # Truncate for whole multibyte characters. +5 bytes for ellipsis
3221                 $comment = $wgContLang->truncate( $comment, 250 );
3222
3223                 $newid = $nt->getArticleID();
3224                 $oldid = $this->getArticleID();
3225                 $latest = $this->getLatestRevId();
3226
3227                 $dbw = wfGetDB( DB_MASTER );
3228                 $now = $dbw->timestamp();
3229
3230                 # Save a null revision in the page's history notifying of the move
3231                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3232                 if ( !is_object( $nullRevision ) ) {
3233                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3234                 }
3235                 $nullRevId = $nullRevision->insertOn( $dbw );
3236
3237                 $article = new Article( $this );
3238                 wfRunHooks( 'NewRevisionFromEditComplete', array( $article, $nullRevision, $latest, $wgUser ) );
3239
3240                 # Rename page entry
3241                 $dbw->update( 'page',
3242                         /* SET */ array(
3243                                 'page_touched'   => $now,
3244                                 'page_namespace' => $nt->getNamespace(),
3245                                 'page_title'     => $nt->getDBkey(),
3246                                 'page_latest'    => $nullRevId,
3247                         ),
3248                         /* WHERE */ array( 'page_id' => $oldid ),
3249                         __METHOD__
3250                 );
3251                 $nt->resetArticleID( $oldid );
3252
3253                 if ( $createRedirect || !$wgUser->isAllowed( 'suppressredirect' ) ) {
3254                         # Insert redirect
3255                         $mwRedir = MagicWord::get( 'redirect' );
3256                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3257                         $redirectArticle = new Article( $this );
3258                         $newid = $redirectArticle->insertOn( $dbw );
3259                         $redirectRevision = new Revision( array(
3260                                 'page'    => $newid,
3261                                 'comment' => $comment,
3262                                 'text'    => $redirectText ) );
3263                         $redirectRevision->insertOn( $dbw );
3264                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3265
3266                         wfRunHooks( 'NewRevisionFromEditComplete', array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3267
3268                         # Record the just-created redirect's linking to the page
3269                         $dbw->insert( 'pagelinks',
3270                                 array(
3271                                         'pl_from'      => $newid,
3272                                         'pl_namespace' => $nt->getNamespace(),
3273                                         'pl_title'     => $nt->getDBkey() ),
3274                                 __METHOD__ );
3275                         $redirectSuppressed = false;
3276                 } else {
3277                         $this->resetArticleID( 0 );
3278                         $redirectSuppressed = true;
3279                 }
3280
3281                 # Log the move
3282                 $log = new LogPage( 'move' );
3283                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText(), 2 => $redirectSuppressed ) );
3284
3285                 # Purge caches as per article creation
3286                 Article::onArticleCreate( $nt );
3287
3288                 # Purge old title from squid
3289                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
3290                 $this->purgeSquid();
3291
3292         }
3293
3294         /**
3295          * Move this page's subpages to be subpages of $nt
3296          *
3297          * @param $nt Title Move target
3298          * @param $auth bool Whether $wgUser's permissions should be checked
3299          * @param $reason string The reason for the move
3300          * @param $createRedirect bool Whether to create redirects from the old subpages to the new ones
3301          *  Ignored if the user doesn't have the 'suppressredirect' right
3302          * @return mixed array with old page titles as keys, and strings (new page titles) or
3303          *  arrays (errors) as values, or an error array with numeric indices if no pages were moved
3304          */
3305         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3306                 global $wgMaximumMovedPages;
3307                 // Check permissions
3308                 if ( !$this->userCan( 'move-subpages' ) )
3309                         return array( 'cant-move-subpages' );
3310                 // Do the source and target namespaces support subpages?
3311                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) )
3312                         return array( 'namespace-nosubpages',
3313                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3314                 if ( !MWNamespace::hasSubpages( $nt->getNamespace() ) )
3315                         return array( 'namespace-nosubpages',
3316                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3317
3318                 $subpages = $this->getSubpages( $wgMaximumMovedPages + 1 );
3319                 $retval = array();
3320                 $count = 0;
3321                 foreach ( $subpages as $oldSubpage ) {
3322                         $count++;
3323                         if ( $count > $wgMaximumMovedPages ) {
3324                                 $retval[$oldSubpage->getPrefixedTitle()] =
3325                                                 array( 'movepage-max-pages',
3326                                                         $wgMaximumMovedPages );
3327                                 break;
3328                         }
3329
3330                         // We don't know whether this function was called before
3331                         // or after moving the root page, so check both
3332                         // $this and $nt
3333                         if ( $oldSubpage->getArticleId() == $this->getArticleId() ||
3334                                         $oldSubpage->getArticleID() == $nt->getArticleId() )
3335                                 // When moving a page to a subpage of itself,
3336                                 // don't move it twice
3337                                 continue;
3338                         $newPageName = preg_replace(
3339                                         '#^' . preg_quote( $this->getDBkey(), '#' ) . '#',
3340                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3341                                         $oldSubpage->getDBkey() );
3342                         if ( $oldSubpage->isTalkPage() ) {
3343                                 $newNs = $nt->getTalkPage()->getNamespace();
3344                         } else {
3345                                 $newNs = $nt->getSubjectPage()->getNamespace();
3346                         }
3347                         # Bug 14385: we need makeTitleSafe because the new page names may
3348                         # be longer than 255 characters.
3349                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3350
3351                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3352                         if ( $success === true ) {
3353                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3354                         } else {
3355                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3356                         }
3357                 }
3358                 return $retval;
3359         }
3360
3361         /**
3362          * Checks if this page is just a one-rev redirect.
3363          * Adds lock, so don't use just for light purposes.
3364          *
3365          * @return \type{\bool}
3366          */
3367         public function isSingleRevRedirect() {
3368                 $dbw = wfGetDB( DB_MASTER );
3369                 # Is it a redirect?
3370                 $row = $dbw->selectRow( 'page',
3371                         array( 'page_is_redirect', 'page_latest', 'page_id' ),
3372                         $this->pageCond(),
3373                         __METHOD__,
3374                         array( 'FOR UPDATE' )
3375                 );
3376                 # Cache some fields we may want
3377                 $this->mArticleID = $row ? intval( $row->page_id ) : 0;
3378                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3379                 $this->mLatestID = $row ? intval( $row->page_latest ) : false;
3380                 if ( !$this->mRedirect ) {
3381                         return false;
3382                 }
3383                 # Does the article have a history?
3384                 $row = $dbw->selectField( array( 'page', 'revision' ),
3385                         'rev_id',
3386                         array( 'page_namespace' => $this->getNamespace(),
3387                                 'page_title' => $this->getDBkey(),
3388                                 'page_id=rev_page',
3389                                 'page_latest != rev_id'
3390                         ),
3391                         __METHOD__,
3392                         array( 'FOR UPDATE' )
3393                 );
3394                 # Return true if there was no history
3395                 return ( $row === false );
3396         }
3397
3398         /**
3399          * Checks if $this can be moved to a given Title
3400          * - Selects for update, so don't call it unless you mean business
3401          *
3402          * @param $nt \type{Title} the new title to check
3403          * @return \type{\bool} TRUE or FALSE
3404          */
3405         public function isValidMoveTarget( $nt ) {
3406                 $dbw = wfGetDB( DB_MASTER );
3407                 # Is it an existsing file?
3408                 if ( $nt->getNamespace() == NS_FILE ) {
3409                         $file = wfLocalFile( $nt );
3410                         if ( $file->exists() ) {
3411                                 wfDebug( __METHOD__ . ": file exists\n" );
3412                                 return false;
3413                         }
3414                 }
3415                 # Is it a redirect with no history?
3416                 if ( !$nt->isSingleRevRedirect() ) {
3417                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3418                         return false;
3419                 }
3420                 # Get the article text
3421                 $rev = Revision::newFromTitle( $nt );
3422                 $text = $rev->getText();
3423                 # Does the redirect point to the source?
3424                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3425                 $m = array();
3426                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
3427                         $redirTitle = Title::newFromText( $m[1] );
3428                         if ( !is_object( $redirTitle ) ||
3429                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3430                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
3431                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3432                                 return false;
3433                         }
3434                 } else {
3435                         # Fail safe
3436                         wfDebug( __METHOD__ . ": failsafe\n" );
3437                         return false;
3438                 }
3439                 return true;
3440         }
3441
3442         /**
3443          * Can this title be added to a user's watchlist?
3444          *
3445          * @return \type{\bool} TRUE or FALSE
3446          */
3447         public function isWatchable() {
3448                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
3449         }
3450
3451         /**
3452          * Get categories to which this Title belongs and return an array of
3453          * categories' names.
3454          *
3455          * @return \type{\array} array an array of parents in the form:
3456          *      $parent => $currentarticle
3457          */
3458         public function getParentCategories() {
3459                 global $wgContLang;
3460
3461                 $titlekey = $this->getArticleId();
3462                 $dbr = wfGetDB( DB_SLAVE );
3463                 $categorylinks = $dbr->tableName( 'categorylinks' );
3464
3465                 # NEW SQL
3466                 $sql = "SELECT * FROM $categorylinks"
3467                      . " WHERE cl_from='$titlekey'"
3468                          . " AND cl_from <> '0'"
3469                          . " ORDER BY cl_sortkey";
3470
3471                 $res = $dbr->query( $sql );
3472
3473                 if ( $dbr->numRows( $res ) > 0 ) {
3474                         foreach ( $res as $row )
3475                                 // $data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
3476                                 $data[$wgContLang->getNSText( NS_CATEGORY ) . ':' . $row->cl_to] = $this->getFullText();
3477                         $dbr->freeResult( $res );
3478                 } else {
3479                         $data = array();
3480                 }
3481                 return $data;
3482         }
3483
3484         /**
3485          * Get a tree of parent categories
3486          *
3487          * @param $children \type{\array} an array with the children in the keys, to check for circular refs
3488          * @return \type{\array} Tree of parent categories
3489          */
3490         public function getParentCategoryTree( $children = array() ) {
3491                 $stack = array();
3492                 $parents = $this->getParentCategories();
3493
3494                 if ( $parents ) {
3495                         foreach ( $parents as $parent => $current ) {
3496                                 if ( array_key_exists( $parent, $children ) ) {
3497                                         # Circular reference
3498                                         $stack[$parent] = array();
3499                                 } else {
3500                                         $nt = Title::newFromText( $parent );
3501                                         if ( $nt ) {
3502                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array( $parent => 1 ) );
3503                                         }
3504                                 }
3505                         }
3506                         return $stack;
3507                 } else {
3508                         return array();
3509                 }
3510         }
3511
3512
3513         /**
3514          * Get an associative array for selecting this title from
3515          * the "page" table
3516          *
3517          * @return \type{\array} Selection array
3518          */
3519         public function pageCond() {
3520                 if ( $this->mArticleID > 0 ) {
3521                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
3522                         return array( 'page_id' => $this->mArticleID );
3523                 } else {
3524                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
3525                 }
3526         }
3527
3528         /**
3529          * Get the revision ID of the previous revision
3530          *
3531          * @param $revId \type{\int} Revision ID. Get the revision that was before this one.
3532          * @param $flags \type{\int} GAID_FOR_UPDATE
3533          * @return \twotypes{\int,\bool} Old revision ID, or FALSE if none exists
3534          */
3535         public function getPreviousRevisionID( $revId, $flags = 0 ) {
3536                 $db = ( $flags & GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3537                 return $db->selectField( 'revision', 'rev_id',
3538                         array(
3539                                 'rev_page' => $this->getArticleId( $flags ),
3540                                 'rev_id < ' . intval( $revId )
3541                         ),
3542                         __METHOD__,
3543                         array( 'ORDER BY' => 'rev_id DESC' )
3544                 );
3545         }
3546
3547         /**
3548          * Get the revision ID of the next revision
3549          *
3550          * @param $revId \type{\int} Revision ID. Get the revision that was after this one.
3551          * @param $flags \type{\int} GAID_FOR_UPDATE
3552          * @return \twotypes{\int,\bool} Next revision ID, or FALSE if none exists
3553          */
3554         public function getNextRevisionID( $revId, $flags = 0 ) {
3555                 $db = ( $flags & GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3556                 return $db->selectField( 'revision', 'rev_id',
3557                         array(
3558                                 'rev_page' => $this->getArticleId( $flags ),
3559                                 'rev_id > ' . intval( $revId )
3560                         ),
3561                         __METHOD__,
3562                         array( 'ORDER BY' => 'rev_id' )
3563                 );
3564         }
3565
3566         /**
3567          * Get the first revision of the page
3568          *
3569          * @param $flags \type{\int} GAID_FOR_UPDATE
3570          * @return Revision (or NULL if page doesn't exist)
3571          */
3572         public function getFirstRevision( $flags = 0 ) {
3573                 $db = ( $flags & GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3574                 $pageId = $this->getArticleId( $flags );
3575                 if ( !$pageId ) return null;
3576                 $row = $db->selectRow( 'revision', '*',
3577                         array( 'rev_page' => $pageId ),
3578                         __METHOD__,
3579                         array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
3580                 );
3581                 if ( !$row ) {
3582                         return null;
3583                 } else {
3584                         return new Revision( $row );
3585                 }
3586         }
3587
3588         /**
3589          * Check if this is a new page
3590          *
3591          * @return bool
3592          */
3593         public function isNewPage() {
3594                 $dbr = wfGetDB( DB_SLAVE );
3595                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
3596         }
3597
3598         /**
3599          * Get the oldest revision timestamp of this page
3600          *
3601          * @return String: MW timestamp
3602          */
3603         public function getEarliestRevTime() {
3604                 $dbr = wfGetDB( DB_SLAVE );
3605                 if ( $this->exists() ) {
3606                         $min = $dbr->selectField( 'revision',
3607                                 'MIN(rev_timestamp)',
3608                                 array( 'rev_page' => $this->getArticleId() ),
3609                                 __METHOD__ );
3610                         return wfTimestampOrNull( TS_MW, $min );
3611                 }
3612                 return null;
3613         }
3614
3615         /**
3616          * Get the number of revisions between the given revision IDs.
3617          * Used for diffs and other things that really need it.
3618          *
3619          * @param $old \type{\int} Revision ID.
3620          * @param $new \type{\int} Revision ID.
3621          * @return \type{\int} Number of revisions between these IDs.
3622          */
3623         public function countRevisionsBetween( $old, $new ) {
3624                 $dbr = wfGetDB( DB_SLAVE );
3625                 return (int)$dbr->selectField( 'revision', 'count(*)',
3626                         'rev_page = ' . intval( $this->getArticleId() ) .
3627                         ' AND rev_id > ' . intval( $old ) .
3628                         ' AND rev_id < ' . intval( $new ),
3629                         __METHOD__
3630                 );
3631         }
3632
3633         /**
3634          * Compare with another title.
3635          *
3636          * @param $title \type{Title}
3637          * @return \type{\bool} TRUE or FALSE
3638          */
3639         public function equals( Title $title ) {
3640                 // Note: === is necessary for proper matching of number-like titles.
3641                 return $this->getInterwiki() === $title->getInterwiki()
3642                         && $this->getNamespace() == $title->getNamespace()
3643                         && $this->getDBkey() === $title->getDBkey();
3644         }
3645
3646         /**
3647          * Callback for usort() to do title sorts by (namespace, title)
3648          *
3649          * @return Integer: result of string comparison, or namespace comparison
3650          */
3651         public static function compare( $a, $b ) {
3652                 if ( $a->getNamespace() == $b->getNamespace() ) {
3653                         return strcmp( $a->getText(), $b->getText() );
3654                 } else {
3655                         return $a->getNamespace() - $b->getNamespace();
3656                 }
3657         }
3658
3659         /**
3660          * Return a string representation of this title
3661          *
3662          * @return \type{\string} String representation of this title
3663          */
3664         public function __toString() {
3665                 return $this->getPrefixedText();
3666         }
3667
3668         /**
3669          * Check if page exists.  For historical reasons, this function simply
3670          * checks for the existence of the title in the page table, and will
3671          * thus return false for interwiki links, special pages and the like.
3672          * If you want to know if a title can be meaningfully viewed, you should
3673          * probably call the isKnown() method instead.
3674          *
3675          * @return \type{\bool}
3676          */
3677         public function exists() {
3678                 return $this->getArticleId() != 0;
3679         }
3680
3681         /**
3682          * Should links to this title be shown as potentially viewable (i.e. as
3683          * "bluelinks"), even if there's no record by this title in the page
3684          * table?
3685          *
3686          * This function is semi-deprecated for public use, as well as somewhat
3687          * misleadingly named.  You probably just want to call isKnown(), which
3688          * calls this function internally.
3689          *
3690          * (ISSUE: Most of these checks are cheap, but the file existence check
3691          * can potentially be quite expensive.  Including it here fixes a lot of
3692          * existing code, but we might want to add an optional parameter to skip
3693          * it and any other expensive checks.)
3694          *
3695          * @return \type{\bool}
3696          */
3697         public function isAlwaysKnown() {
3698                 if ( $this->mInterwiki != '' ) {
3699                         return true;  // any interwiki link might be viewable, for all we know
3700                 }
3701                 switch( $this->mNamespace ) {
3702                 case NS_MEDIA:
3703                 case NS_FILE:
3704                         return wfFindFile( $this );  // file exists, possibly in a foreign repo
3705                 case NS_SPECIAL:
3706                         return SpecialPage::exists( $this->getDBkey() );  // valid special page
3707                 case NS_MAIN:
3708                         return $this->mDbkeyform == '';  // selflink, possibly with fragment
3709                 case NS_MEDIAWIKI:
3710                         // If the page is form Mediawiki:message/lang, calling wfMsgWeirdKey causes
3711                         // the full l10n of that language to be loaded. That takes much memory and
3712                         // isn't needed. So we strip the language part away.
3713                         list( $basename, /* rest */ ) = explode( '/', $this->mDbkeyform, 2 );
3714                         return (bool)wfMsgWeirdKey( $basename );  // known system message
3715                 default:
3716                         return false;
3717                 }
3718         }
3719
3720         /**
3721          * Does this title refer to a page that can (or might) be meaningfully
3722          * viewed?  In particular, this function may be used to determine if
3723          * links to the title should be rendered as "bluelinks" (as opposed to
3724          * "redlinks" to non-existent pages).
3725          *
3726          * @return \type{\bool}
3727          */
3728         public function isKnown() {
3729                 return $this->exists() || $this->isAlwaysKnown();
3730         }
3731
3732         /**
3733          * Does this page have source text?
3734          *
3735          * @return Boolean
3736          */
3737         public function hasSourceText() {
3738                 if ( $this->exists() )
3739                         return true;
3740
3741                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
3742                         // If the page doesn't exist but is a known system message, default
3743                         // message content will be displayed, same for language subpages
3744                         // Also, if the page is form Mediawiki:message/lang, calling wfMsgWeirdKey
3745                         // causes the full l10n of that language to be loaded. That takes much
3746                         // memory and isn't needed. So we strip the language part away.
3747                         list( $basename, /* rest */ ) = explode( '/', $this->mDbkeyform, 2 );
3748                         return (bool)wfMsgWeirdKey( $basename );
3749                 }
3750
3751                 return false;
3752         }
3753
3754         /**
3755         * Is this in a namespace that allows actual pages?
3756         *
3757         * @return \type{\bool}
3758         * @internal note -- uses hardcoded namespace index instead of constants
3759         */
3760         public function canExist() {
3761                 return $this->mNamespace >= 0 && $this->mNamespace != NS_MEDIA;
3762         }
3763
3764         /**
3765          * Update page_touched timestamps and send squid purge messages for
3766          * pages linking to this title. May be sent to the job queue depending
3767          * on the number of links. Typically called on create and delete.
3768          */
3769         public function touchLinks() {
3770                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
3771                 $u->doUpdate();
3772
3773                 if ( $this->getNamespace() == NS_CATEGORY ) {
3774                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
3775                         $u->doUpdate();
3776                 }
3777         }
3778
3779         /**
3780          * Get the last touched timestamp
3781          *
3782          * @param $db DatabaseBase: optional db
3783          * @return \type{\string} Last touched timestamp
3784          */
3785         public function getTouched( $db = null ) {
3786                 $db = isset( $db ) ? $db : wfGetDB( DB_SLAVE );
3787                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
3788                 return $touched;
3789         }
3790
3791         /**
3792          * Get the timestamp when this page was updated since the user last saw it.
3793          *
3794          * @param $user User
3795          * @return Mixed: string/null
3796          */
3797         public function getNotificationTimestamp( $user = null ) {
3798                 global $wgUser, $wgShowUpdatedMarker;
3799                 // Assume current user if none given
3800                 if ( !$user ) $user = $wgUser;
3801                 // Check cache first
3802                 $uid = $user->getId();
3803                 if ( isset( $this->mNotificationTimestamp[$uid] ) ) {
3804                         return $this->mNotificationTimestamp[$uid];
3805                 }
3806                 if ( !$uid || !$wgShowUpdatedMarker ) {
3807                         return $this->mNotificationTimestamp[$uid] = false;
3808                 }
3809                 // Don't cache too much!
3810                 if ( count( $this->mNotificationTimestamp ) >= self::CACHE_MAX ) {
3811                         $this->mNotificationTimestamp = array();
3812                 }
3813                 $dbr = wfGetDB( DB_SLAVE );
3814                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
3815                         'wl_notificationtimestamp',
3816                         array( 'wl_namespace' => $this->getNamespace(),
3817                                 'wl_title' => $this->getDBkey(),
3818                                 'wl_user' => $user->getId()
3819                         ),
3820                         __METHOD__
3821                 );
3822                 return $this->mNotificationTimestamp[$uid];
3823         }
3824
3825         /**
3826          * Get the trackback URL for this page
3827          *
3828          * @return \type{\string} Trackback URL
3829          */
3830         public function trackbackURL() {
3831                 global $wgScriptPath, $wgServer, $wgScriptExtension;
3832
3833                 return "$wgServer$wgScriptPath/trackback$wgScriptExtension?article="
3834                         . htmlspecialchars( urlencode( $this->getPrefixedDBkey() ) );
3835         }
3836
3837         /**
3838          * Get the trackback RDF for this page
3839          *
3840          * @return \type{\string} Trackback RDF
3841          */
3842         public function trackbackRDF() {
3843                 $url = htmlspecialchars( $this->getFullURL() );
3844                 $title = htmlspecialchars( $this->getText() );
3845                 $tburl = $this->trackbackURL();
3846
3847                 // Autodiscovery RDF is placed in comments so HTML validator
3848                 // won't barf. This is a rather icky workaround, but seems
3849                 // frequently used by this kind of RDF thingy.
3850                 //
3851                 // Spec: http://www.sixapart.com/pronet/docs/trackback_spec
3852                 return "<!--
3853 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
3854          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
3855          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
3856 <rdf:Description
3857    rdf:about=\"$url\"
3858    dc:identifier=\"$url\"
3859    dc:title=\"$title\"
3860    trackback:ping=\"$tburl\" />
3861 </rdf:RDF>
3862 -->";
3863         }
3864
3865         /**
3866          * Generate strings used for xml 'id' names in monobook tabs
3867          *
3868          * @param $prepend string defaults to 'nstab-'
3869          * @return \type{\string} XML 'id' name
3870          */
3871         public function getNamespaceKey( $prepend = 'nstab-' ) {
3872                 global $wgContLang;
3873                 // Gets the subject namespace if this title
3874                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
3875                 // Checks if cononical namespace name exists for namespace
3876                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
3877                         // Uses canonical namespace name
3878                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
3879                 } else {
3880                         // Uses text of namespace
3881                         $namespaceKey = $this->getSubjectNsText();
3882                 }
3883                 // Makes namespace key lowercase
3884                 $namespaceKey = $wgContLang->lc( $namespaceKey );
3885                 // Uses main
3886                 if ( $namespaceKey == '' ) {
3887                         $namespaceKey = 'main';
3888                 }
3889                 // Changes file to image for backwards compatibility
3890                 if ( $namespaceKey == 'file' ) {
3891                         $namespaceKey = 'image';
3892                 }
3893                 return $prepend . $namespaceKey;
3894         }
3895
3896         /**
3897          * Returns true if this is a special page.
3898          *
3899          * @return boolean
3900          */
3901         public function isSpecialPage( ) {
3902                 return $this->getNamespace() == NS_SPECIAL;
3903         }
3904
3905         /**
3906          * Returns true if this title resolves to the named special page
3907          *
3908          * @param $name \type{\string} The special page name
3909          * @return boolean
3910          */
3911         public function isSpecial( $name ) {
3912                 if ( $this->getNamespace() == NS_SPECIAL ) {
3913                         list( $thisName, /* $subpage */ ) = SpecialPage::resolveAliasWithSubpage( $this->getDBkey() );
3914                         if ( $name == $thisName ) {
3915                                 return true;
3916                         }
3917                 }
3918                 return false;
3919         }
3920
3921         /**
3922          * If the Title refers to a special page alias which is not the local default,
3923          *
3924          * @return \type{Title} A new Title which points to the local default.
3925          *         Otherwise, returns $this.
3926          */
3927         public function fixSpecialName() {
3928                 if ( $this->getNamespace() == NS_SPECIAL ) {
3929                         $canonicalName = SpecialPage::resolveAlias( $this->mDbkeyform );
3930                         if ( $canonicalName ) {
3931                                 $localName = SpecialPage::getLocalNameFor( $canonicalName );
3932                                 if ( $localName != $this->mDbkeyform ) {
3933                                         return Title::makeTitle( NS_SPECIAL, $localName );
3934                                 }
3935                         }
3936                 }
3937                 return $this;
3938         }
3939
3940         /**
3941          * Is this Title in a namespace which contains content?
3942          * In other words, is this a content page, for the purposes of calculating
3943          * statistics, etc?
3944          *
3945          * @return \type{\bool}
3946          */
3947         public function isContentPage() {
3948                 return MWNamespace::isContent( $this->getNamespace() );
3949         }
3950
3951         /**
3952          * Get all extant redirects to this Title
3953          *
3954          * @param $ns \twotypes{\int,\null} Single namespace to consider;
3955          *            NULL to consider all namespaces
3956          * @return \type{\arrayof{Title}} Redirects to this title
3957          */
3958         public function getRedirectsHere( $ns = null ) {
3959                 $redirs = array();
3960
3961                 $dbr = wfGetDB( DB_SLAVE );
3962                 $where = array(
3963                         'rd_namespace' => $this->getNamespace(),
3964                         'rd_title' => $this->getDBkey(),
3965                         'rd_from = page_id'
3966                 );
3967                 if ( !is_null( $ns ) ) $where['page_namespace'] = $ns;
3968
3969                 $res = $dbr->select(
3970                         array( 'redirect', 'page' ),
3971                         array( 'page_namespace', 'page_title' ),
3972                         $where,
3973                         __METHOD__
3974                 );
3975
3976
3977                 foreach ( $res as $row ) {
3978                         $redirs[] = self::newFromRow( $row );
3979                 }
3980                 return $redirs;
3981         }
3982
3983         /**
3984          * Check if this Title is a valid redirect target
3985          *
3986          * @return \type{\bool}
3987          */
3988         public function isValidRedirectTarget() {
3989                 global $wgInvalidRedirectTargets;
3990
3991                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
3992                 if ( $this->isSpecial( 'Userlogout' ) ) {
3993                         return false;
3994                 }
3995
3996                 foreach ( $wgInvalidRedirectTargets as $target ) {
3997                         if ( $this->isSpecial( $target ) ) {
3998                                 return false;
3999                         }
4000                 }
4001
4002                 return true;
4003         }
4004
4005         /**
4006          * Get a backlink cache object
4007          *
4008          * @return object BacklinkCache
4009          */
4010         function getBacklinkCache() {
4011                 if ( is_null( $this->mBacklinkCache ) ) {
4012                         $this->mBacklinkCache = new BacklinkCache( $this );
4013                 }
4014                 return $this->mBacklinkCache;
4015         }
4016
4017         /**
4018          * Whether the magic words __INDEX__ and __NOINDEX__ function for
4019          * this page.
4020          *
4021          * @return Boolean
4022          */
4023         public function canUseNoindex() {
4024                 global $wgArticleRobotPolicies, $wgContentNamespaces,
4025                        $wgExemptFromUserRobotsControl;
4026
4027                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
4028                         ? $wgContentNamespaces
4029                         : $wgExemptFromUserRobotsControl;
4030
4031                 return !in_array( $this->mNamespace, $bannedNamespaces );
4032
4033         }
4034
4035         /**
4036          * Returns restriction types for the current Title
4037          *
4038          * @return array applicable restriction types
4039          */
4040         public function getRestrictionTypes() {
4041                 global $wgRestrictionTypes;
4042                 $types = $this->exists() ? $wgRestrictionTypes : array( 'create' );
4043
4044                 if ( $this->getNamespace() == NS_FILE ) {
4045                         $types[] = 'upload';
4046                 }
4047
4048                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
4049
4050                 return $types;
4051         }
4052 }