includes/Title.php

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