includes/Title.php

   1 <?php
   2 /**
   3  * See title.txt
   4  *
   5  * @package MediaWiki
   6  */
   7
   8 /** */
   9 require_once( 'normal/UtfNormal.php' );
  10
  11 define ( 'GAID_FOR_UPDATE', 1 );
  12
  13 # Title::newFromTitle maintains a cache to avoid
  14 # expensive re-normalization of commonly used titles.
  15 # On a batch operation this can become a memory leak
  16 # if not bounded. After hitting this many titles,
  17 # reset the cache.
  18 define( 'MW_TITLECACHE_MAX', 1000 );
  19
  20 /**
  21  * Title class
  22  * - Represents a title, which may contain an interwiki designation or namespace
  23  * - Can fetch various kinds of data from the database, albeit inefficiently.
  24  *
  25  * @package MediaWiki
  26  */
  27 class Title {
  28         /**
  29          * Static cache variables
  30          */
  31         static private $titleCache=array();
  32         static private $interwikiCache=array();
  33
  34
  35         /**
  36          * All member variables should be considered private
  37          * Please use the accessor functions
  38          */
  39
  40          /**#@+
  41          * @private
  42          */
  43
  44         var $mTextform;           # Text form (spaces not underscores) of the main part
  45         var $mUrlform;            # URL-encoded form of the main part
  46         var $mDbkeyform;          # Main part with underscores
  47         var $mNamespace;          # Namespace index, i.e. one of the NS_xxxx constants
  48         var $mInterwiki;          # Interwiki prefix (or null string)
  49         var $mFragment;           # Title fragment (i.e. the bit after the #)
  50         var $mArticleID;          # Article ID, fetched from the link cache on demand
  51         var $mLatestID;         # ID of most recent revision
  52         var $mRestrictions;       # Array of groups allowed to edit this article
  53                                 # Only null or "sysop" are supported
  54         var $mRestrictionsLoaded; # Boolean for initialisation on demand
  55         var $mPrefixedText;       # Text form including namespace/interwiki, initialised on demand
  56         var $mDefaultNamespace;   # Namespace index when there is no namespace
  57                             # Zero except in {{transclusion}} tags
  58         var $mWatched;      # Is $wgUser watching this page? NULL if unfilled, accessed through userIsWatching()
  59         /**#@-*/
  60
  61
  62         /**
  63          * Constructor
  64          * @private
  65          */
  66         /* private */ function Title() {
  67                 $this->mInterwiki = $this->mUrlform =
  68                 $this->mTextform = $this->mDbkeyform = '';
  69                 $this->mArticleID = -1;
  70                 $this->mNamespace = NS_MAIN;
  71                 $this->mRestrictionsLoaded = false;
  72                 $this->mRestrictions = array();
  73                 # Dont change the following, NS_MAIN is hardcoded in several place
  74                 # See bug #696
  75                 $this->mDefaultNamespace = NS_MAIN;
  76                 $this->mWatched = NULL;
  77                 $this->mLatestID = false;
  78         }
  79
  80         /**
  81          * Create a new Title from a prefixed DB key
  82          * @param string $key The database key, which has underscores
  83          *      instead of spaces, possibly including namespace and
  84          *      interwiki prefixes
  85          * @return Title the new object, or NULL on an error
  86          * @static
  87          * @access public
  88          */
  89         /* static */ function newFromDBkey( $key ) {
  90                 $t = new Title();
  91                 $t->mDbkeyform = $key;
  92                 if( $t->secureAndSplit() )
  93                         return $t;
  94                 else
  95                         return NULL;
  96         }
  97
  98         /**
  99          * Create a new Title from text, such as what one would
 100          * find in a link. Decodes any HTML entities in the text.
 101          *
 102          * @param string $text the link text; spaces, prefixes,
 103          *      and an initial ':' indicating the main namespace
 104          *      are accepted
 105          * @param int $defaultNamespace the namespace to use if
 106          *      none is specified by a prefix
 107          * @return Title the new object, or NULL on an error
 108          * @static
 109          * @access public
 110          */
 111         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 112                 $fname = 'Title::newFromText';
 113
 114                 if( is_object( $text ) ) {
 115                         throw new MWException( 'Title::newFromText given an object' );
 116                 }
 117
 118                 /**
 119                  * Wiki pages often contain multiple links to the same page.
 120                  * Title normalization and parsing can become expensive on
 121                  * pages with many links, so we can save a little time by
 122                  * caching them.
 123                  *
 124                  * In theory these are value objects and won't get changed...
 125                  */
 126                 if( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 127                         return Title::$titleCache[$text];
 128                 }
 129
 130                 /**
 131                  * Convert things like &eacute; &#257; or &#x3017; into real text...
 132                  */
 133                 $filteredText = Sanitizer::decodeCharReferences( $text );
 134
 135                 $t = new Title();
 136                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 137                 $t->mDefaultNamespace = $defaultNamespace;
 138
 139                 static $cachedcount = 0 ;
 140                 if( $t->secureAndSplit() ) {
 141                         if( $defaultNamespace == NS_MAIN ) {
 142                                 if( $cachedcount >= MW_TITLECACHE_MAX ) {
 143                                         # Avoid memory leaks on mass operations...
 144                                         Title::$titleCache = array();
 145                                         $cachedcount=0;
 146                                 }
 147                                 $cachedcount++;
 148                                 Title::$titleCache[$text] =& $t;
 149                         }
 150                         return $t;
 151                 } else {
 152                         $ret = NULL;
 153                         return $ret;
 154                 }
 155         }
 156
 157         /**
 158          * Create a new Title from URL-encoded text. Ensures that
 159          * the given title's length does not exceed the maximum.
 160          * @param string $url the title, as might be taken from a URL
 161          * @return Title the new object, or NULL on an error
 162          * @static
 163          * @access public
 164          */
 165         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          * @access public
 193          * @static
 194          */
 195         function newFromID( $id ) {
 196                 $fname = 'Title::newFromID';
 197                 $dbr =& wfGetDB( DB_SLAVE );
 198                 $row = $dbr->selectRow( 'page', array( 'page_namespace', 'page_title' ),
 199                         array( 'page_id' => $id ), $fname );
 200                 if ( $row !== false ) {
 201                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 202                 } else {
 203                         $title = NULL;
 204                 }
 205                 return $title;
 206         }
 207
 208         /**
 209          * Make an array of titles from an array of IDs
 210          */
 211         function newFromIDs( $ids ) {
 212                 $dbr =& wfGetDB( DB_SLAVE );
 213                 $res = $dbr->select( 'page', array( 'page_namespace', 'page_title' ),
 214                         'page_id IN (' . $dbr->makeList( $ids ) . ')', __METHOD__ );
 215
 216                 $titles = array();
 217                 while ( $row = $dbr->fetchObject( $res ) ) {
 218                         $titles[] = Title::makeTitle( $row->page_namespace, $row->page_title );
 219                 }
 220                 return $titles;
 221         }
 222
 223         /**
 224          * Create a new Title from a namespace index and a DB key.
 225          * It's assumed that $ns and $title are *valid*, for instance when
 226          * they came directly from the database or a special page name.
 227          * For convenience, spaces are converted to underscores so that
 228          * eg user_text fields can be used directly.
 229          *
 230          * @param int $ns the namespace of the article
 231          * @param string $title the unprefixed database key form
 232          * @return Title the new object
 233          * @static
 234          * @access public
 235          */
 236         public static function &makeTitle( $ns, $title ) {
 237                 $t = new Title();
 238                 $t->mInterwiki = '';
 239                 $t->mFragment = '';
 240                 $t->mNamespace = intval( $ns );
 241                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 242                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 243                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 244                 $t->mTextform = str_replace( '_', ' ', $title );
 245                 return $t;
 246         }
 247
 248         /**
 249          * Create a new Title from a namespace index and a DB key.
 250          * The parameters will be checked for validity, which is a bit slower
 251          * than makeTitle() but safer for user-provided data.
 252          *
 253          * @param int $ns the namespace of the article
 254          * @param string $title the database key form
 255          * @return Title the new object, or NULL on an error
 256          * @static
 257          * @access public
 258          */
 259         public static function makeTitleSafe( $ns, $title ) {
 260                 $t = new Title();
 261                 $t->mDbkeyform = Title::makeName( $ns, $title );
 262                 if( $t->secureAndSplit() ) {
 263                         return $t;
 264                 } else {
 265                         return NULL;
 266                 }
 267         }
 268
 269         /**
 270          * Create a new Title for the Main Page
 271          *
 272          * @static
 273          * @return Title the new object
 274          * @access public
 275          */
 276         public static function newMainPage() {
 277                 return Title::newFromText( wfMsgForContent( 'mainpage' ) );
 278         }
 279
 280         /**
 281          * Create a new Title for a redirect
 282          * @param string $text the redirect title text
 283          * @return Title the new object, or NULL if the text is not a
 284          *      valid redirect
 285          * @static
 286          * @access public
 287          */
 288         public static function newFromRedirect( $text ) {
 289                 $mwRedir = MagicWord::get( 'redirect' );
 290                 $rt = NULL;
 291                 if ( $mwRedir->matchStart( $text ) ) {
 292                         if ( preg_match( '/\[{2}(.*?)(?:\||\]{2})/', $text, $m ) ) {
 293                                 # categories are escaped using : for example one can enter:
 294                                 # #REDIRECT [[:Category:Music]]. Need to remove it.
 295                                 if ( substr($m[1],0,1) == ':') {
 296                                         # We don't want to keep the ':'
 297                                         $m[1] = substr( $m[1], 1 );
 298                                 }
 299
 300                                 $rt = Title::newFromText( $m[1] );
 301                                 # Disallow redirects to Special:Userlogout
 302                                 if ( !is_null($rt) && $rt->getNamespace() == NS_SPECIAL && preg_match( '/^Userlogout/i', $rt->getText() ) ) {
 303                                         $rt = NULL;
 304                                 }
 305                         }
 306                 }
 307                 return $rt;
 308         }
 309
 310 #----------------------------------------------------------------------------
 311 #       Static functions
 312 #----------------------------------------------------------------------------
 313
 314         /**
 315          * Get the prefixed DB key associated with an ID
 316          * @param int $id the page_id of the article
 317          * @return Title an object representing the article, or NULL
 318          *      if no such article was found
 319          * @static
 320          * @access public
 321          */
 322         function nameOf( $id ) {
 323                 $fname = 'Title::nameOf';
 324                 $dbr =& wfGetDB( DB_SLAVE );
 325
 326                 $s = $dbr->selectRow( 'page', array( 'page_namespace','page_title' ),  array( 'page_id' => $id ), $fname );
 327                 if ( $s === false ) { return NULL; }
 328
 329                 $n = Title::makeName( $s->page_namespace, $s->page_title );
 330                 return $n;
 331         }
 332
 333         /**
 334          * Get a regex character class describing the legal characters in a link
 335          * @return string the list of characters, not delimited
 336          * @static
 337          * @access public
 338          */
 339         public static function legalChars() {
 340                 global $wgLegalTitleChars;
 341                 return $wgLegalTitleChars;
 342         }
 343
 344         /**
 345          * Get a string representation of a title suitable for
 346          * including in a search index
 347          *
 348          * @param int $ns a namespace index
 349          * @param string $title text-form main part
 350          * @return string a stripped-down title string ready for the
 351          *      search index
 352          */
 353         /* static */ function indexTitle( $ns, $title ) {
 354                 global $wgContLang;
 355
 356                 $lc = SearchEngine::legalSearchChars() . '&#;';
 357                 $t = $wgContLang->stripForSearch( $title );
 358                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 359                 $t = strtolower( $t );
 360
 361                 # Handle 's, s'
 362                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 363                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 364
 365                 $t = preg_replace( "/\\s+/", ' ', $t );
 366
 367                 if ( $ns == NS_IMAGE ) {
 368                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 369                 }
 370                 return trim( $t );
 371         }
 372
 373         /*
 374          * Make a prefixed DB key from a DB key and a namespace index
 375          * @param int $ns numerical representation of the namespace
 376          * @param string $title the DB key form the title
 377          * @return string the prefixed form of the title
 378          */
 379         public static function makeName( $ns, $title ) {
 380                 global $wgContLang;
 381
 382                 $n = $wgContLang->getNsText( $ns );
 383                 return $n == '' ? $title : "$n:$title";
 384         }
 385
 386         /**
 387          * Returns the URL associated with an interwiki prefix
 388          * @param string $key the interwiki prefix (e.g. "MeatBall")
 389          * @return the associated URL, containing "$1", which should be
 390          *      replaced by an article title
 391          * @static (arguably)
 392          * @access public
 393          */
 394         function getInterwikiLink( $key )  {
 395                 global $wgMemc, $wgDBname, $wgInterwikiExpiry;
 396                 global $wgInterwikiCache;
 397                 $fname = 'Title::getInterwikiLink';
 398
 399                 $key = strtolower( $key );
 400
 401                 $k = $wgDBname.':interwiki:'.$key;
 402                 if( array_key_exists( $k, Title::$interwikiCache ) ) {
 403                         return Title::$interwikiCache[$k]->iw_url;
 404                 }
 405
 406                 if ($wgInterwikiCache) {
 407                         return Title::getInterwikiCached( $key );
 408                 }
 409
 410                 $s = $wgMemc->get( $k );
 411                 # Ignore old keys with no iw_local
 412                 if( $s && isset( $s->iw_local ) && isset($s->iw_trans)) {
 413                         Title::$interwikiCache[$k] = $s;
 414                         return $s->iw_url;
 415                 }
 416
 417                 $dbr =& wfGetDB( DB_SLAVE );
 418                 $res = $dbr->select( 'interwiki',
 419                         array( 'iw_url', 'iw_local', 'iw_trans' ),
 420                         array( 'iw_prefix' => $key ), $fname );
 421                 if( !$res ) {
 422                         return '';
 423                 }
 424
 425                 $s = $dbr->fetchObject( $res );
 426                 if( !$s ) {
 427                         # Cache non-existence: create a blank object and save it to memcached
 428                         $s = (object)false;
 429                         $s->iw_url = '';
 430                         $s->iw_local = 0;
 431                         $s->iw_trans = 0;
 432                 }
 433                 $wgMemc->set( $k, $s, $wgInterwikiExpiry );
 434                 Title::$interwikiCache[$k] = $s;
 435
 436                 return $s->iw_url;
 437         }
 438
 439         /**
 440          * Fetch interwiki prefix data from local cache in constant database
 441          *
 442          * More logic is explained in DefaultSettings
 443          *
 444          * @return string URL of interwiki site
 445          * @access public
 446          */
 447         function getInterwikiCached( $key ) {
 448                 global $wgDBname, $wgInterwikiCache, $wgInterwikiScopes, $wgInterwikiFallbackSite;
 449                 static $db, $site;
 450
 451                 if (!$db)
 452                         $db=dba_open($wgInterwikiCache,'r','cdb');
 453                 /* Resolve site name */
 454                 if ($wgInterwikiScopes>=3 and !$site) {
 455                         $site = dba_fetch("__sites:{$wgDBname}", $db);
 456                         if ($site=="")
 457                                 $site = $wgInterwikiFallbackSite;
 458                 }
 459                 $value = dba_fetch("{$wgDBname}:{$key}", $db);
 460                 if ($value=='' and $wgInterwikiScopes>=3) {
 461                         /* try site-level */
 462                         $value = dba_fetch("_{$site}:{$key}", $db);
 463                 }
 464                 if ($value=='' and $wgInterwikiScopes>=2) {
 465                         /* try globals */
 466                         $value = dba_fetch("__global:{$key}", $db);
 467                 }
 468                 if ($value=='undef')
 469                         $value='';
 470                 $s = (object)false;
 471                 $s->iw_url = '';
 472                 $s->iw_local = 0;
 473                 $s->iw_trans = 0;
 474                 if ($value!='') {
 475                         list($local,$url)=explode(' ',$value,2);
 476                         $s->iw_url=$url;
 477                         $s->iw_local=(int)$local;
 478                 }
 479                 Title::$interwikiCache[$wgDBname.':interwiki:'.$key] = $s;
 480                 return $s->iw_url;
 481         }
 482         /**
 483          * Determine whether the object refers to a page within
 484          * this project.
 485          *
 486          * @return bool TRUE if this is an in-project interwiki link
 487          *      or a wikilink, FALSE otherwise
 488          * @access public
 489          */
 490         function isLocal() {
 491                 global $wgDBname;
 492
 493                 if ( $this->mInterwiki != '' ) {
 494                         # Make sure key is loaded into cache
 495                         $this->getInterwikiLink( $this->mInterwiki );
 496                         $k = $wgDBname.':interwiki:' . $this->mInterwiki;
 497                         return (bool)(Title::$interwikiCache[$k]->iw_local);
 498                 } else {
 499                         return true;
 500                 }
 501         }
 502
 503         /**
 504          * Determine whether the object refers to a page within
 505          * this project and is transcludable.
 506          *
 507          * @return bool TRUE if this is transcludable
 508          * @access public
 509          */
 510         function isTrans() {
 511                 global $wgDBname;
 512
 513                 if ($this->mInterwiki == '')
 514                         return false;
 515                 # Make sure key is loaded into cache
 516                 $this->getInterwikiLink( $this->mInterwiki );
 517                 $k = $wgDBname.':interwiki:' . $this->mInterwiki;
 518                 return (bool)(Title::$interwikiCache[$k]->iw_trans);
 519         }
 520
 521         /**
 522          * Update the page_touched field for an array of title objects
 523          * @todo Inefficient unless the IDs are already loaded into the
 524          *      link cache
 525          * @param array $titles an array of Title objects to be touched
 526          * @param string $timestamp the timestamp to use instead of the
 527          *      default current time
 528          * @static
 529          * @access public
 530          */
 531         function touchArray( $titles, $timestamp = '' ) {
 532
 533                 if ( count( $titles ) == 0 ) {
 534                         return;
 535                 }
 536                 $dbw =& wfGetDB( DB_MASTER );
 537                 if ( $timestamp == '' ) {
 538                         $timestamp = $dbw->timestamp();
 539                 }
 540                 /*
 541                 $page = $dbw->tableName( 'page' );
 542                 $sql = "UPDATE $page SET page_touched='{$timestamp}' WHERE page_id IN (";
 543                 $first = true;
 544
 545                 foreach ( $titles as $title ) {
 546                         if ( $wgUseFileCache ) {
 547                                 $cm = new CacheManager($title);
 548                                 @unlink($cm->fileCacheName());
 549                         }
 550
 551                         if ( ! $first ) {
 552                                 $sql .= ',';
 553                         }
 554                         $first = false;
 555                         $sql .= $title->getArticleID();
 556                 }
 557                 $sql .= ')';
 558                 if ( ! $first ) {
 559                         $dbw->query( $sql, 'Title::touchArray' );
 560                 }
 561                 */
 562                 // hack hack hack -- brion 2005-07-11. this was unfriendly to db.
 563                 // do them in small chunks:
 564                 $fname = 'Title::touchArray';
 565                 foreach( $titles as $title ) {
 566                         $dbw->update( 'page',
 567                                 array( 'page_touched' => $timestamp ),
 568                                 array(
 569                                         'page_namespace' => $title->getNamespace(),
 570                                         'page_title'     => $title->getDBkey() ),
 571                                 $fname );
 572                 }
 573         }
 574
 575 #----------------------------------------------------------------------------
 576 #       Other stuff
 577 #----------------------------------------------------------------------------
 578
 579         /** Simple accessors */
 580         /**
 581          * Get the text form (spaces not underscores) of the main part
 582          * @return string
 583          * @access public
 584          */
 585         function getText() { return $this->mTextform; }
 586         /**
 587          * Get the URL-encoded form of the main part
 588          * @return string
 589          * @access public
 590          */
 591         function getPartialURL() { return $this->mUrlform; }
 592         /**
 593          * Get the main part with underscores
 594          * @return string
 595          * @access public
 596          */
 597         function getDBkey() { return $this->mDbkeyform; }
 598         /**
 599          * Get the namespace index, i.e. one of the NS_xxxx constants
 600          * @return int
 601          * @access public
 602          */
 603         function getNamespace() { return $this->mNamespace; }
 604         /**
 605          * Get the namespace text
 606          * @return string
 607          * @access public
 608          */
 609         function getNsText() {
 610                 global $wgContLang;
 611                 return $wgContLang->getNsText( $this->mNamespace );
 612         }
 613         /**
 614          * Get the namespace text of the subject (rather than talk) page
 615          * @return string
 616          * @access public
 617          */
 618         function getSubjectNsText() {
 619                 global $wgContLang;
 620                 return $wgContLang->getNsText( Namespace::getSubject( $this->mNamespace ) );
 621         }
 622
 623         /**
 624          * Get the namespace text of the talk page
 625          * @return string
 626          */
 627         function getTalkNsText() {
 628                 global $wgContLang;
 629                 return( $wgContLang->getNsText( Namespace::getTalk( $this->mNamespace ) ) );
 630         }
 631
 632         /**
 633          * Could this title have a corresponding talk page?
 634          * @return bool
 635          */
 636         function canTalk() {
 637                 return( Namespace::canTalk( $this->mNamespace ) );
 638         }
 639
 640         /**
 641          * Get the interwiki prefix (or null string)
 642          * @return string
 643          * @access public
 644          */
 645         function getInterwiki() { return $this->mInterwiki; }
 646         /**
 647          * Get the Title fragment (i.e. the bit after the #)
 648          * @return string
 649          * @access public
 650          */
 651         function getFragment() { return $this->mFragment; }
 652         /**
 653          * Get the default namespace index, for when there is no namespace
 654          * @return int
 655          * @access public
 656          */
 657         function getDefaultNamespace() { return $this->mDefaultNamespace; }
 658
 659         /**
 660          * Get title for search index
 661          * @return string a stripped-down title string ready for the
 662          *      search index
 663          */
 664         function getIndexTitle() {
 665                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 666         }
 667
 668         /**
 669          * Get the prefixed database key form
 670          * @return string the prefixed title, with underscores and
 671          *      any interwiki and namespace prefixes
 672          * @access public
 673          */
 674         function getPrefixedDBkey() {
 675                 $s = $this->prefix( $this->mDbkeyform );
 676                 $s = str_replace( ' ', '_', $s );
 677                 return $s;
 678         }
 679
 680         /**
 681          * Get the prefixed title with spaces.
 682          * This is the form usually used for display
 683          * @return string the prefixed title, with spaces
 684          * @access public
 685          */
 686         function getPrefixedText() {
 687                 if ( empty( $this->mPrefixedText ) ) { // FIXME: bad usage of empty() ?
 688                         $s = $this->prefix( $this->mTextform );
 689                         $s = str_replace( '_', ' ', $s );
 690                         $this->mPrefixedText = $s;
 691                 }
 692                 return $this->mPrefixedText;
 693         }
 694
 695         /**
 696          * Get the prefixed title with spaces, plus any fragment
 697          * (part beginning with '#')
 698          * @return string the prefixed title, with spaces and
 699          *      the fragment, including '#'
 700          * @access public
 701          */
 702         function getFullText() {
 703                 $text = $this->getPrefixedText();
 704                 if( '' != $this->mFragment ) {
 705                         $text .= '#' . $this->mFragment;
 706                 }
 707                 return $text;
 708         }
 709
 710         /**
 711          * Get the base name, i.e. the leftmost parts before the /
 712          * @return string Base name
 713          */
 714         function getBaseText() {
 715                 global $wgNamespacesWithSubpages;
 716                 if( isset( $wgNamespacesWithSubpages[ $this->mNamespace ] ) && $wgNamespacesWithSubpages[ $this->mNamespace ] ) {
 717                         $parts = explode( '/', $this->getText() );
 718                         # Don't discard the real title if there's no subpage involved
 719                         if( count( $parts ) > 1 )
 720                                 unset( $parts[ count( $parts ) - 1 ] );
 721                         return implode( '/', $parts );
 722                 } else {
 723                         return $this->getText();
 724                 }
 725         }
 726
 727         /**
 728          * Get the lowest-level subpage name, i.e. the rightmost part after /
 729          * @return string Subpage name
 730          */
 731         function getSubpageText() {
 732                 global $wgNamespacesWithSubpages;
 733                 if( isset( $wgNamespacesWithSubpages[ $this->mNamespace ] ) && $wgNamespacesWithSubpages[ $this->mNamespace ] ) {
 734                         $parts = explode( '/', $this->mTextform );
 735                         return( $parts[ count( $parts ) - 1 ] );
 736                 } else {
 737                         return( $this->mTextform );
 738                 }
 739         }
 740
 741         /**
 742          * Get a URL-encoded form of the subpage text
 743          * @return string URL-encoded subpage name
 744          */
 745         function getSubpageUrlForm() {
 746                 $text = $this->getSubpageText();
 747                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
 748                 $text = str_replace( '%28', '(', str_replace( '%29', ')', $text ) ); # Clean up the URL; per below, this might not be safe
 749                 return( $text );
 750         }
 751
 752         /**
 753          * Get a URL-encoded title (not an actual URL) including interwiki
 754          * @return string the URL-encoded form
 755          * @access public
 756          */
 757         function getPrefixedURL() {
 758                 $s = $this->prefix( $this->mDbkeyform );
 759                 $s = str_replace( ' ', '_', $s );
 760
 761                 $s = wfUrlencode ( $s ) ;
 762
 763                 # Cleaning up URL to make it look nice -- is this safe?
 764                 $s = str_replace( '%28', '(', $s );
 765                 $s = str_replace( '%29', ')', $s );
 766
 767                 return $s;
 768         }
 769
 770         /**
 771          * Get a real URL referring to this title, with interwiki link and
 772          * fragment
 773          *
 774          * @param string $query an optional query string, not used
 775          *      for interwiki links
 776          * @return string the URL
 777          * @access public
 778          */
 779         function getFullURL( $query = '' ) {
 780                 global $wgContLang, $wgServer, $wgRequest;
 781
 782                 if ( '' == $this->mInterwiki ) {
 783                         $url = $this->getLocalUrl( $query );
 784
 785                         // Ugly quick hack to avoid duplicate prefixes (bug 4571 etc)
 786                         // Correct fix would be to move the prepending elsewhere.
 787                         if ($wgRequest->getVal('action') != 'render') {
 788                                 $url = $wgServer . $url;
 789                         }
 790                 } else {
 791                         $baseUrl = $this->getInterwikiLink( $this->mInterwiki );
 792
 793                         $namespace = $wgContLang->getNsText( $this->mNamespace );
 794                         if ( '' != $namespace ) {
 795                                 # Can this actually happen? Interwikis shouldn't be parsed.
 796                                 $namespace .= ':';
 797                         }
 798                         $url = str_replace( '$1', $namespace . $this->mUrlform, $baseUrl );
 799                         if( $query != '' ) {
 800                                 if( false === strpos( $url, '?' ) ) {
 801                                         $url .= '?';
 802                                 } else {
 803                                         $url .= '&';
 804                                 }
 805                                 $url .= $query;
 806                         }
 807                 }
 808
 809                 # Finally, add the fragment.
 810                 if ( '' != $this->mFragment ) {
 811                         $url .= '#' . $this->mFragment;
 812                 }
 813
 814                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
 815                 return $url;
 816         }
 817
 818         /**
 819          * Get a URL with no fragment or server name.  If this page is generated
 820          * with action=render, $wgServer is prepended.
 821          * @param string $query an optional query string; if not specified,
 822          *      $wgArticlePath will be used.
 823          * @return string the URL
 824          * @access public
 825          */
 826         function getLocalURL( $query = '' ) {
 827                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
 828
 829                 if ( $this->isExternal() ) {
 830                         $url = $this->getFullURL();
 831                         if ( $query ) {
 832                                 // This is currently only used for edit section links in the
 833                                 // context of interwiki transclusion. In theory we should
 834                                 // append the query to the end of any existing query string,
 835                                 // but interwiki transclusion is already broken in that case.
 836                                 $url .= "?$query";
 837                         }
 838                 } else {
 839                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 840                         if ( $query == '' ) {
 841                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
 842                         } else {
 843                                 global $wgActionPaths;
 844                                 $url = false;
 845                                 if( !empty( $wgActionPaths ) &&
 846                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
 847                                 {
 848                                         $action = urldecode( $matches[2] );
 849                                         if( isset( $wgActionPaths[$action] ) ) {
 850                                                 $query = $matches[1];
 851                                                 if( isset( $matches[4] ) ) $query .= $matches[4];
 852                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
 853                                                 if( $query != '' ) $url .= '?' . $query;
 854                                         }
 855                                 }
 856                                 if ( $url === false ) {
 857                                         if ( $query == '-' ) {
 858                                                 $query = '';
 859                                         }
 860                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
 861                                 }
 862                         }
 863
 864                         // FIXME: this causes breakage in various places when we
 865                         // actually expected a local URL and end up with dupe prefixes.
 866                         if ($wgRequest->getVal('action') == 'render') {
 867                                 $url = $wgServer . $url;
 868                         }
 869                 }
 870                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
 871                 return $url;
 872         }
 873
 874         /**
 875          * Get an HTML-escaped version of the URL form, suitable for
 876          * using in a link, without a server name or fragment
 877          * @param string $query an optional query string
 878          * @return string the URL
 879          * @access public
 880          */
 881         function escapeLocalURL( $query = '' ) {
 882                 return htmlspecialchars( $this->getLocalURL( $query ) );
 883         }
 884
 885         /**
 886          * Get an HTML-escaped version of the URL form, suitable for
 887          * using in a link, including the server name and fragment
 888          *
 889          * @return string the URL
 890          * @param string $query an optional query string
 891          * @access public
 892          */
 893         function escapeFullURL( $query = '' ) {
 894                 return htmlspecialchars( $this->getFullURL( $query ) );
 895         }
 896
 897         /**
 898          * Get the URL form for an internal link.
 899          * - Used in various Squid-related code, in case we have a different
 900          * internal hostname for the server from the exposed one.
 901          *
 902          * @param string $query an optional query string
 903          * @return string the URL
 904          * @access public
 905          */
 906         function getInternalURL( $query = '' ) {
 907                 global $wgInternalServer;
 908                 $url = $wgInternalServer . $this->getLocalURL( $query );
 909                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
 910                 return $url;
 911         }
 912
 913         /**
 914          * Get the edit URL for this Title
 915          * @return string the URL, or a null string if this is an
 916          *      interwiki link
 917          * @access public
 918          */
 919         function getEditURL() {
 920                 if ( '' != $this->mInterwiki ) { return ''; }
 921                 $s = $this->getLocalURL( 'action=edit' );
 922
 923                 return $s;
 924         }
 925
 926         /**
 927          * Get the HTML-escaped displayable text form.
 928          * Used for the title field in <a> tags.
 929          * @return string the text, including any prefixes
 930          * @access public
 931          */
 932         function getEscapedText() {
 933                 return htmlspecialchars( $this->getPrefixedText() );
 934         }
 935
 936         /**
 937          * Is this Title interwiki?
 938          * @return boolean
 939          * @access public
 940          */
 941         function isExternal() { return ( '' != $this->mInterwiki ); }
 942
 943         /**
 944          * Is this page "semi-protected" - the *only* protection is autoconfirm?
 945          *
 946          * @param string Action to check (default: edit)
 947          * @return bool
 948          */
 949         function isSemiProtected( $action = 'edit' ) {
 950                 $restrictions = $this->getRestrictions( $action );
 951                 # We do a full compare because this could be an array
 952                 foreach( $restrictions as $restriction ) {
 953                         if( strtolower( $restriction ) != 'autoconfirmed' ) {
 954                                 return( false );
 955                         }
 956                 }
 957                 return( true );
 958         }
 959
 960         /**
 961          * Does the title correspond to a protected article?
 962          * @param string $what the action the page is protected from,
 963          *      by default checks move and edit
 964          * @return boolean
 965          * @access public
 966          */
 967         function isProtected( $action = '' ) {
 968                 global $wgRestrictionLevels;
 969                 if ( -1 == $this->mNamespace ) { return true; }
 970
 971                 if( $action == 'edit' || $action == '' ) {
 972                         $r = $this->getRestrictions( 'edit' );
 973                         foreach( $wgRestrictionLevels as $level ) {
 974                                 if( in_array( $level, $r ) && $level != '' ) {
 975                                         return( true );
 976                                 }
 977                         }
 978                 }
 979
 980                 if( $action == 'move' || $action == '' ) {
 981                         $r = $this->getRestrictions( 'move' );
 982                         foreach( $wgRestrictionLevels as $level ) {
 983                                 if( in_array( $level, $r ) && $level != '' ) {
 984                                         return( true );
 985                                 }
 986                         }
 987                 }
 988
 989                 return false;
 990         }
 991
 992         /**
 993          * Is $wgUser is watching this page?
 994          * @return boolean
 995          * @access public
 996          */
 997         function userIsWatching() {
 998                 global $wgUser;
 999
1000                 if ( is_null( $this->mWatched ) ) {
1001                         if ( -1 == $this->mNamespace || 0 == $wgUser->getID()) {
1002                                 $this->mWatched = false;
1003                         } else {
1004                                 $this->mWatched = $wgUser->isWatched( $this );
1005                         }
1006                 }
1007                 return $this->mWatched;
1008         }
1009
1010         /**
1011          * Can $wgUser perform $action this page?
1012          * @param string $action action that permission needs to be checked for
1013          * @return boolean
1014          * @private
1015          */
1016         function userCan($action) {
1017                 $fname = 'Title::userCan';
1018                 wfProfileIn( $fname );
1019
1020                 global $wgUser;
1021
1022                 $result = null;
1023                 wfRunHooks( 'userCan', array( &$this, &$wgUser, $action, &$result ) );
1024                 if ( $result !== null ) {
1025                         wfProfileOut( $fname );
1026                         return $result;
1027                 }
1028
1029                 if( NS_SPECIAL == $this->mNamespace ) {
1030                         wfProfileOut( $fname );
1031                         return false;
1032                 }
1033                 // XXX: This is the code that prevents unprotecting a page in NS_MEDIAWIKI
1034                 // from taking effect -ævar
1035                 if( NS_MEDIAWIKI == $this->mNamespace &&
1036                     !$wgUser->isAllowed('editinterface') ) {
1037                         wfProfileOut( $fname );
1038                         return false;
1039                 }
1040
1041                 if( $this->mDbkeyform == '_' ) {
1042                         # FIXME: Is this necessary? Shouldn't be allowed anyway...
1043                         wfProfileOut( $fname );
1044                         return false;
1045                 }
1046
1047                 # protect css/js subpages of user pages
1048                 # XXX: this might be better using restrictions
1049                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssJsSubpage() from working
1050                 if( NS_USER == $this->mNamespace
1051                         && preg_match("/\\.(css|js)$/", $this->mTextform )
1052                         && !$wgUser->isAllowed('editinterface')
1053                         && !preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) ) {
1054                         wfProfileOut( $fname );
1055                         return false;
1056                 }
1057
1058                 foreach( $this->getRestrictions($action) as $right ) {
1059                         // Backwards compatibility, rewrite sysop -> protect
1060                         if ( $right == 'sysop' ) {
1061                                 $right = 'protect';
1062                         }
1063                         if( '' != $right && !$wgUser->isAllowed( $right ) ) {
1064                                 wfProfileOut( $fname );
1065                                 return false;
1066                         }
1067                 }
1068
1069                 if( $action == 'move' &&
1070                         !( $this->isMovable() && $wgUser->isAllowed( 'move' ) ) ) {
1071                         wfProfileOut( $fname );
1072                         return false;
1073                 }
1074
1075                 if( $action == 'create' ) {
1076                         if( (  $this->isTalkPage() && !$wgUser->isAllowed( 'createtalk' ) ) ||
1077                                 ( !$this->isTalkPage() && !$wgUser->isAllowed( 'createpage' ) ) ) {
1078                                 return false;
1079                         }
1080                 }
1081
1082                 wfProfileOut( $fname );
1083                 return true;
1084         }
1085
1086         /**
1087          * Can $wgUser edit this page?
1088          * @return boolean
1089          * @access public
1090          */
1091         function userCanEdit() {
1092                 return $this->userCan('edit');
1093         }
1094
1095         /**
1096          * Can $wgUser create this page?
1097          * @return boolean
1098          * @access public
1099          */
1100         function userCanCreate() {
1101                 return $this->userCan('create');
1102         }
1103
1104         /**
1105          * Can $wgUser move this page?
1106          * @return boolean
1107          * @access public
1108          */
1109         function userCanMove() {
1110                 return $this->userCan('move');
1111         }
1112
1113         /**
1114          * Would anybody with sufficient privileges be able to move this page?
1115          * Some pages just aren't movable.
1116          *
1117          * @return boolean
1118          * @access public
1119          */
1120         function isMovable() {
1121                 return Namespace::isMovable( $this->getNamespace() )
1122                         && $this->getInterwiki() == '';
1123         }
1124
1125         /**
1126          * Can $wgUser read this page?
1127          * @return boolean
1128          * @access public
1129          */
1130         function userCanRead() {
1131                 global $wgUser;
1132
1133                 $result = null;
1134                 wfRunHooks( 'userCan', array( &$this, &$wgUser, 'read', &$result ) );
1135                 if ( $result !== null ) {
1136                         return $result;
1137                 }
1138
1139                 if( $wgUser->isAllowed('read') ) {
1140                         return true;
1141                 } else {
1142                         global $wgWhitelistRead;
1143
1144                         /** If anon users can create an account,
1145                             they need to reach the login page first! */
1146                         if( $wgUser->isAllowed( 'createaccount' )
1147                             && $this->getNamespace() == NS_SPECIAL
1148                             && $this->getText() == 'Userlogin' ) {
1149                                 return true;
1150                         }
1151
1152                         /** some pages are explicitly allowed */
1153                         $name = $this->getPrefixedText();
1154                         if( $wgWhitelistRead && in_array( $name, $wgWhitelistRead ) ) {
1155                                 return true;
1156                         }
1157
1158                         # Compatibility with old settings
1159                         if( $wgWhitelistRead && $this->getNamespace() == NS_MAIN ) {
1160                                 if( in_array( ':' . $name, $wgWhitelistRead ) ) {
1161                                         return true;
1162                                 }
1163                         }
1164                 }
1165                 return false;
1166         }
1167
1168         /**
1169          * Is this a talk page of some sort?
1170          * @return bool
1171          * @access public
1172          */
1173         function isTalkPage() {
1174                 return Namespace::isTalk( $this->getNamespace() );
1175         }
1176
1177         /**
1178          * Is this a .css or .js subpage of a user page?
1179          * @return bool
1180          * @access public
1181          */
1182         function isCssJsSubpage() {
1183                 return ( NS_USER == $this->mNamespace and preg_match("/\\.(css|js)$/", $this->mTextform ) );
1184         }
1185         /**
1186          * Is this a *valid* .css or .js subpage of a user page?
1187          * Check that the corresponding skin exists
1188          */
1189         function isValidCssJsSubpage() {
1190                 if ( $this->isCssJsSubpage() ) {
1191                         $skinNames = Skin::getSkinNames();
1192                         return array_key_exists( $this->getSkinFromCssJsSubpage(), $skinNames );
1193                 } else {
1194                         return false;
1195                 }
1196         }
1197         /**
1198          * Trim down a .css or .js subpage title to get the corresponding skin name
1199          */
1200         function getSkinFromCssJsSubpage() {
1201                 $subpage = explode( '/', $this->mTextform );
1202                 $subpage = $subpage[ count( $subpage ) - 1 ];
1203                 return( str_replace( array( '.css', '.js' ), array( '', '' ), $subpage ) );
1204         }
1205         /**
1206          * Is this a .css subpage of a user page?
1207          * @return bool
1208          * @access public
1209          */
1210         function isCssSubpage() {
1211                 return ( NS_USER == $this->mNamespace and preg_match("/\\.css$/", $this->mTextform ) );
1212         }
1213         /**
1214          * Is this a .js subpage of a user page?
1215          * @return bool
1216          * @access public
1217          */
1218         function isJsSubpage() {
1219                 return ( NS_USER == $this->mNamespace and preg_match("/\\.js$/", $this->mTextform ) );
1220         }
1221         /**
1222          * Protect css/js subpages of user pages: can $wgUser edit
1223          * this page?
1224          *
1225          * @return boolean
1226          * @todo XXX: this might be better using restrictions
1227          * @access public
1228          */
1229         function userCanEditCssJsSubpage() {
1230                 global $wgUser;
1231                 return ( $wgUser->isAllowed('editinterface') or preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1232         }
1233
1234         /**
1235          * Loads a string into mRestrictions array
1236          * @param string $res restrictions in string format
1237          * @access public
1238          */
1239         function loadRestrictions( $res ) {
1240                 foreach( explode( ':', trim( $res ) ) as $restrict ) {
1241                         $temp = explode( '=', trim( $restrict ) );
1242                         if(count($temp) == 1) {
1243                                 // old format should be treated as edit/move restriction
1244                                 $this->mRestrictions["edit"] = explode( ',', trim( $temp[0] ) );
1245                                 $this->mRestrictions["move"] = explode( ',', trim( $temp[0] ) );
1246                         } else {
1247                                 $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
1248                         }
1249                 }
1250                 $this->mRestrictionsLoaded = true;
1251         }
1252
1253         /**
1254          * Accessor/initialisation for mRestrictions
1255          * @param string $action action that permission needs to be checked for
1256          * @return array the array of groups allowed to edit this article
1257          * @access public
1258          */
1259         function getRestrictions($action) {
1260                 $id = $this->getArticleID();
1261                 if ( 0 == $id ) { return array(); }
1262
1263                 if ( ! $this->mRestrictionsLoaded ) {
1264                         $dbr =& wfGetDB( DB_SLAVE );
1265                         $res = $dbr->selectField( 'page', 'page_restrictions', 'page_id='.$id );
1266                         $this->loadRestrictions( $res );
1267                 }
1268                 if( isset( $this->mRestrictions[$action] ) ) {
1269                         return $this->mRestrictions[$action];
1270                 }
1271                 return array();
1272         }
1273
1274         /**
1275          * Is there a version of this page in the deletion archive?
1276          * @return int the number of archived revisions
1277          * @access public
1278          */
1279         function isDeleted() {
1280                 $fname = 'Title::isDeleted';
1281                 if ( $this->getNamespace() < 0 ) {
1282                         $n = 0;
1283                 } else {
1284                         $dbr =& wfGetDB( DB_SLAVE );
1285                         $n = $dbr->selectField( 'archive', 'COUNT(*)', array( 'ar_namespace' => $this->getNamespace(),
1286                                 'ar_title' => $this->getDBkey() ), $fname );
1287                         if( $this->getNamespace() == NS_IMAGE ) {
1288                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
1289                                         array( 'fa_name' => $this->getDBkey() ), $fname );
1290                         }
1291                 }
1292                 return (int)$n;
1293         }
1294
1295         /**
1296          * Get the article ID for this Title from the link cache,
1297          * adding it if necessary
1298          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select
1299          *      for update
1300          * @return int the ID
1301          * @access public
1302          */
1303         function getArticleID( $flags = 0 ) {
1304                 $linkCache =& LinkCache::singleton();
1305                 if ( $flags & GAID_FOR_UPDATE ) {
1306                         $oldUpdate = $linkCache->forUpdate( true );
1307                         $this->mArticleID = $linkCache->addLinkObj( $this );
1308                         $linkCache->forUpdate( $oldUpdate );
1309                 } else {
1310                         if ( -1 == $this->mArticleID ) {
1311                                 $this->mArticleID = $linkCache->addLinkObj( $this );
1312                         }
1313                 }
1314                 return $this->mArticleID;
1315         }
1316
1317         function getLatestRevID() {
1318                 if ($this->mLatestID !== false)
1319                         return $this->mLatestID;
1320
1321                 $db =& wfGetDB(DB_SLAVE);
1322                 return $this->mLatestID = $db->selectField( 'revision',
1323                         "max(rev_id)",
1324                         array('rev_page' => $this->getArticleID()),
1325                         'Title::getLatestRevID' );
1326         }
1327
1328         /**
1329          * This clears some fields in this object, and clears any associated
1330          * keys in the "bad links" section of the link cache.
1331          *
1332          * - This is called from Article::insertNewArticle() to allow
1333          * loading of the new page_id. It's also called from
1334          * Article::doDeleteArticle()
1335          *
1336          * @param int $newid the new Article ID
1337          * @access public
1338          */
1339         function resetArticleID( $newid ) {
1340                 $linkCache =& LinkCache::singleton();
1341                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
1342
1343                 if ( 0 == $newid ) { $this->mArticleID = -1; }
1344                 else { $this->mArticleID = $newid; }
1345                 $this->mRestrictionsLoaded = false;
1346                 $this->mRestrictions = array();
1347         }
1348
1349         /**
1350          * Updates page_touched for this page; called from LinksUpdate.php
1351          * @return bool true if the update succeded
1352          * @access public
1353          */
1354         function invalidateCache() {
1355                 global $wgUseFileCache;
1356
1357                 if ( wfReadOnly() ) {
1358                         return;
1359                 }
1360
1361                 $dbw =& wfGetDB( DB_MASTER );
1362                 $success = $dbw->update( 'page',
1363                         array( /* SET */
1364                                 'page_touched' => $dbw->timestamp()
1365                         ), array( /* WHERE */
1366                                 'page_namespace' => $this->getNamespace() ,
1367                                 'page_title' => $this->getDBkey()
1368                         ), 'Title::invalidateCache'
1369                 );
1370
1371                 if ($wgUseFileCache) {
1372                         $cache = new CacheManager($this);
1373                         @unlink($cache->fileCacheName());
1374                 }
1375
1376                 return $success;
1377         }
1378
1379         /**
1380          * Prefix some arbitrary text with the namespace or interwiki prefix
1381          * of this object
1382          *
1383          * @param string $name the text
1384          * @return string the prefixed text
1385          * @private
1386          */
1387         /* private */ function prefix( $name ) {
1388                 global $wgContLang;
1389
1390                 $p = '';
1391                 if ( '' != $this->mInterwiki ) {
1392                         $p = $this->mInterwiki . ':';
1393                 }
1394                 if ( 0 != $this->mNamespace ) {
1395                         $p .= $wgContLang->getNsText( $this->mNamespace ) . ':';
1396                 }
1397                 return $p . $name;
1398         }
1399
1400         /**
1401          * Secure and split - main initialisation function for this object
1402          *
1403          * Assumes that mDbkeyform has been set, and is urldecoded
1404          * and uses underscores, but not otherwise munged.  This function
1405          * removes illegal characters, splits off the interwiki and
1406          * namespace prefixes, sets the other forms, and canonicalizes
1407          * everything.
1408          * @return bool true on success
1409          * @private
1410          */
1411         /* private */ function secureAndSplit() {
1412                 global $wgContLang, $wgLocalInterwiki, $wgCapitalLinks;
1413                 $fname = 'Title::secureAndSplit';
1414
1415                 # Initialisation
1416                 static $rxTc = false;
1417                 if( !$rxTc ) {
1418                         # % is needed as well
1419                         $rxTc = '/[^' . Title::legalChars() . ']|%[0-9A-Fa-f]{2}/S';
1420                 }
1421
1422                 $this->mInterwiki = $this->mFragment = '';
1423                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
1424
1425                 # Clean up whitespace
1426                 #
1427                 $t = preg_replace( '/[ _]+/', '_', $this->mDbkeyform );
1428                 $t = trim( $t, '_' );
1429
1430                 if ( '' == $t ) {
1431                         return false;
1432                 }
1433
1434                 if( false !== strpos( $t, UTF8_REPLACEMENT ) ) {
1435                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
1436                         return false;
1437                 }
1438
1439                 $this->mDbkeyform = $t;
1440
1441                 # Initial colon indicates main namespace rather than specified default
1442                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
1443                 if ( ':' == $t{0} ) {
1444                         $this->mNamespace = NS_MAIN;
1445                         $t = substr( $t, 1 ); # remove the colon but continue processing
1446                 }
1447
1448                 # Namespace or interwiki prefix
1449                 $firstPass = true;
1450                 do {
1451                         if ( preg_match( "/^(.+?)_*:_*(.*)$/S", $t, $m ) ) {
1452                                 $p = $m[1];
1453                                 $lowerNs = strtolower( $p );
1454                                 if ( $ns = Namespace::getCanonicalIndex( $lowerNs ) ) {
1455                                         # Canonical namespace
1456                                         $t = $m[2];
1457                                         $this->mNamespace = $ns;
1458                                 } elseif ( $ns = $wgContLang->getNsIndex( $lowerNs )) {
1459                                         # Ordinary namespace
1460                                         $t = $m[2];
1461                                         $this->mNamespace = $ns;
1462                                 } elseif( $this->getInterwikiLink( $p ) ) {
1463                                         if( !$firstPass ) {
1464                                                 # Can't make a local interwiki link to an interwiki link.
1465                                                 # That's just crazy!
1466                                                 return false;
1467                                         }
1468
1469                                         # Interwiki link
1470                                         $t = $m[2];
1471                                         $this->mInterwiki = strtolower( $p );
1472
1473                                         # Redundant interwiki prefix to the local wiki
1474                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
1475                                                 if( $t == '' ) {
1476                                                         # Can't have an empty self-link
1477                                                         return false;
1478                                                 }
1479                                                 $this->mInterwiki = '';
1480                                                 $firstPass = false;
1481                                                 # Do another namespace split...
1482                                                 continue;
1483                                         }
1484
1485                                         # If there's an initial colon after the interwiki, that also
1486                                         # resets the default namespace
1487                                         if ( $t !== '' && $t[0] == ':' ) {
1488                                                 $this->mNamespace = NS_MAIN;
1489                                                 $t = substr( $t, 1 );
1490                                         }
1491                                 }
1492                                 # If there's no recognized interwiki or namespace,
1493                                 # then let the colon expression be part of the title.
1494                         }
1495                         break;
1496                 } while( true );
1497                 $r = $t;
1498
1499                 # We already know that some pages won't be in the database!
1500                 #
1501                 if ( '' != $this->mInterwiki || -1 == $this->mNamespace ) {
1502                         $this->mArticleID = 0;
1503                 }
1504                 $f = strstr( $r, '#' );
1505                 if ( false !== $f ) {
1506                         $this->mFragment = substr( $f, 1 );
1507                         $r = substr( $r, 0, strlen( $r ) - strlen( $f ) );
1508                         # remove whitespace again: prevents "Foo_bar_#"
1509                         # becoming "Foo_bar_"
1510                         $r = preg_replace( '/_*$/', '', $r );
1511                 }
1512
1513                 # Reject illegal characters.
1514                 #
1515                 if( preg_match( $rxTc, $r ) ) {
1516                         return false;
1517                 }
1518
1519                 /**
1520                  * Pages with "/./" or "/../" appearing in the URLs will
1521                  * often be unreachable due to the way web browsers deal
1522                  * with 'relative' URLs. Forbid them explicitly.
1523                  */
1524                 if ( strpos( $r, '.' ) !== false &&
1525                      ( $r === '.' || $r === '..' ||
1526                        strpos( $r, './' ) === 0  ||
1527                        strpos( $r, '../' ) === 0 ||
1528                        strpos( $r, '/./' ) !== false ||
1529                        strpos( $r, '/../' ) !== false ) )
1530                 {
1531                         return false;
1532                 }
1533
1534                 # We shouldn't need to query the DB for the size.
1535                 #$maxSize = $dbr->textFieldSize( 'page', 'page_title' );
1536                 if ( strlen( $r ) > 255 ) {
1537                         return false;
1538                 }
1539
1540                 /**
1541                  * Normally, all wiki links are forced to have
1542                  * an initial capital letter so [[foo]] and [[Foo]]
1543                  * point to the same place.
1544                  *
1545                  * Don't force it for interwikis, since the other
1546                  * site might be case-sensitive.
1547                  */
1548                 if( $wgCapitalLinks && $this->mInterwiki == '') {
1549                         $t = $wgContLang->ucfirst( $r );
1550                 } else {
1551                         $t = $r;
1552                 }
1553
1554                 /**
1555                  * Can't make a link to a namespace alone...
1556                  * "empty" local links can only be self-links
1557                  * with a fragment identifier.
1558                  */
1559                 if( $t == '' &&
1560                         $this->mInterwiki == '' &&
1561                         $this->mNamespace != NS_MAIN ) {
1562                         return false;
1563                 }
1564
1565                 // Any remaining initial :s are illegal.
1566                 if ( $t !== '' && ':' == $t{0} ) {
1567                         return false;
1568                 }
1569
1570                 # Fill fields
1571                 $this->mDbkeyform = $t;
1572                 $this->mUrlform = wfUrlencode( $t );
1573
1574                 $this->mTextform = str_replace( '_', ' ', $t );
1575
1576                 return true;
1577         }
1578
1579         /**
1580          * Get a Title object associated with the talk page of this article
1581          * @return Title the object for the talk page
1582          * @access public
1583          */
1584         function getTalkPage() {
1585                 return Title::makeTitle( Namespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1586         }
1587
1588         /**
1589          * Get a title object associated with the subject page of this
1590          * talk page
1591          *
1592          * @return Title the object for the subject page
1593          * @access public
1594          */
1595         function getSubjectPage() {
1596                 return Title::makeTitle( Namespace::getSubject( $this->getNamespace() ), $this->getDBkey() );
1597         }
1598
1599         /**
1600          * Get an array of Title objects linking to this Title
1601          * Also stores the IDs in the link cache.
1602          *
1603          * WARNING: do not use this function on arbitrary user-supplied titles!
1604          * On heavily-used templates it will max out the memory.
1605          *
1606          * @param string $options may be FOR UPDATE
1607          * @return array the Title objects linking here
1608          * @access public
1609          */
1610         function getLinksTo( $options = '', $table = 'pagelinks', $prefix = 'pl' ) {
1611                 $linkCache =& LinkCache::singleton();
1612                 $id = $this->getArticleID();
1613
1614                 if ( $options ) {
1615                         $db =& wfGetDB( DB_MASTER );
1616                 } else {
1617                         $db =& wfGetDB( DB_SLAVE );
1618                 }
1619
1620                 $res = $db->select( array( 'page', $table ),
1621                         array( 'page_namespace', 'page_title', 'page_id' ),
1622                         array(
1623                                 "{$prefix}_from=page_id",
1624                                 "{$prefix}_namespace" => $this->getNamespace(),
1625                                 "{$prefix}_title"     => $this->getDbKey() ),
1626                         'Title::getLinksTo',
1627                         $options );
1628
1629                 $retVal = array();
1630                 if ( $db->numRows( $res ) ) {
1631                         while ( $row = $db->fetchObject( $res ) ) {
1632                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
1633                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj );
1634                                         $retVal[] = $titleObj;
1635                                 }
1636                         }
1637                 }
1638                 $db->freeResult( $res );
1639                 return $retVal;
1640         }
1641
1642         /**
1643          * Get an array of Title objects using this Title as a template
1644          * Also stores the IDs in the link cache.
1645          *
1646          * WARNING: do not use this function on arbitrary user-supplied titles!
1647          * On heavily-used templates it will max out the memory.
1648          *
1649          * @param string $options may be FOR UPDATE
1650          * @return array the Title objects linking here
1651          * @access public
1652          */
1653         function getTemplateLinksTo( $options = '' ) {
1654                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
1655         }
1656
1657         /**
1658          * Get an array of Title objects referring to non-existent articles linked from this page
1659          *
1660          * @param string $options may be FOR UPDATE
1661          * @return array the Title objects
1662          * @access public
1663          */
1664         function getBrokenLinksFrom( $options = '' ) {
1665                 if ( $options ) {
1666                         $db =& wfGetDB( DB_MASTER );
1667                 } else {
1668                         $db =& wfGetDB( DB_SLAVE );
1669                 }
1670
1671                 $res = $db->safeQuery(
1672                           "SELECT pl_namespace, pl_title
1673                              FROM !
1674                         LEFT JOIN !
1675                                ON pl_namespace=page_namespace
1676                               AND pl_title=page_title
1677                             WHERE pl_from=?
1678                               AND page_namespace IS NULL
1679                                   !",
1680                         $db->tableName( 'pagelinks' ),
1681                         $db->tableName( 'page' ),
1682                         $this->getArticleId(),
1683                         $options );
1684
1685                 $retVal = array();
1686                 if ( $db->numRows( $res ) ) {
1687                         while ( $row = $db->fetchObject( $res ) ) {
1688                                 $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
1689                         }
1690                 }
1691                 $db->freeResult( $res );
1692                 return $retVal;
1693         }
1694
1695
1696         /**
1697          * Get a list of URLs to purge from the Squid cache when this
1698          * page changes
1699          *
1700          * @return array the URLs
1701          * @access public
1702          */
1703         function getSquidURLs() {
1704                 return array(
1705                         $this->getInternalURL(),
1706                         $this->getInternalURL( 'action=history' )
1707                 );
1708         }
1709
1710         function purgeSquid() {
1711                 global $wgUseSquid;
1712                 if ( $wgUseSquid ) {
1713                         $urls = $this->getSquidURLs();
1714                         $u = new SquidUpdate( $urls );
1715                         $u->doUpdate();
1716                 }
1717         }
1718
1719         /**
1720          * Move this page without authentication
1721          * @param Title &$nt the new page Title
1722          * @access public
1723          */
1724         function moveNoAuth( &$nt ) {
1725                 return $this->moveTo( $nt, false );
1726         }
1727
1728         /**
1729          * Check whether a given move operation would be valid.
1730          * Returns true if ok, or a message key string for an error message
1731          * if invalid. (Scarrrrry ugly interface this.)
1732          * @param Title &$nt the new title
1733          * @param bool $auth indicates whether $wgUser's permissions
1734          *      should be checked
1735          * @return mixed true on success, message name on failure
1736          * @access public
1737          */
1738         function isValidMoveOperation( &$nt, $auth = true ) {
1739                 if( !$this or !$nt ) {
1740                         return 'badtitletext';
1741                 }
1742                 if( $this->equals( $nt ) ) {
1743                         return 'selfmove';
1744                 }
1745                 if( !$this->isMovable() || !$nt->isMovable() ) {
1746                         return 'immobile_namespace';
1747                 }
1748
1749                 $oldid = $this->getArticleID();
1750                 $newid = $nt->getArticleID();
1751
1752                 if ( strlen( $nt->getDBkey() ) < 1 ) {
1753                         return 'articleexists';
1754                 }
1755                 if ( ( '' == $this->getDBkey() ) ||
1756                          ( !$oldid ) ||
1757                      ( '' == $nt->getDBkey() ) ) {
1758                         return 'badarticleerror';
1759                 }
1760
1761                 if ( $auth && (
1762                                 !$this->userCanEdit() || !$nt->userCanEdit() ||
1763                                 !$this->userCanMove() || !$nt->userCanMove() ) ) {
1764                         return 'protectedpage';
1765                 }
1766
1767                 # The move is allowed only if (1) the target doesn't exist, or
1768                 # (2) the target is a redirect to the source, and has no history
1769                 # (so we can undo bad moves right after they're done).
1770
1771                 if ( 0 != $newid ) { # Target exists; check for validity
1772                         if ( ! $this->isValidMoveTarget( $nt ) ) {
1773                                 return 'articleexists';
1774                         }
1775                 }
1776                 return true;
1777         }
1778
1779         /**
1780          * Move a title to a new location
1781          * @param Title &$nt the new title
1782          * @param bool $auth indicates whether $wgUser's permissions
1783          *      should be checked
1784          * @return mixed true on success, message name on failure
1785          * @access public
1786          */
1787         function moveTo( &$nt, $auth = true, $reason = '' ) {
1788                 $err = $this->isValidMoveOperation( $nt, $auth );
1789                 if( is_string( $err ) ) {
1790                         return $err;
1791                 }
1792
1793                 $pageid = $this->getArticleID();
1794                 if( $nt->exists() ) {
1795                         $this->moveOverExistingRedirect( $nt, $reason );
1796                         $pageCountChange = 0;
1797                 } else { # Target didn't exist, do normal move.
1798                         $this->moveToNewTitle( $nt, $reason );
1799                         $pageCountChange = 1;
1800                 }
1801                 $redirid = $this->getArticleID();
1802
1803                 # Fixing category links (those without piped 'alternate' names) to be sorted under the new title
1804                 $dbw =& wfGetDB( DB_MASTER );
1805                 $categorylinks = $dbw->tableName( 'categorylinks' );
1806                 $sql = "UPDATE $categorylinks SET cl_sortkey=" . $dbw->addQuotes( $nt->getPrefixedText() ) .
1807                         " WHERE cl_from=" . $dbw->addQuotes( $pageid ) .
1808                         " AND cl_sortkey=" . $dbw->addQuotes( $this->getPrefixedText() );
1809                 $dbw->query( $sql, 'SpecialMovepage::doSubmit' );
1810
1811                 # Update watchlists
1812
1813                 $oldnamespace = $this->getNamespace() & ~1;
1814                 $newnamespace = $nt->getNamespace() & ~1;
1815                 $oldtitle = $this->getDBkey();
1816                 $newtitle = $nt->getDBkey();
1817
1818                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
1819                         WatchedItem::duplicateEntries( $this, $nt );
1820                 }
1821
1822                 # Update search engine
1823                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
1824                 $u->doUpdate();
1825                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
1826                 $u->doUpdate();
1827
1828                 # Update site_stats
1829                 if ( $this->getNamespace() == NS_MAIN and $nt->getNamespace() != NS_MAIN ) {
1830                         # Moved out of main namespace
1831                         # not viewed, edited, removing
1832                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange);
1833                 } elseif ( $this->getNamespace() != NS_MAIN and $nt->getNamespace() == NS_MAIN ) {
1834                         # Moved into main namespace
1835                         # not viewed, edited, adding
1836                         $u = new SiteStatsUpdate( 0, 1, +1, $pageCountChange );
1837                 } elseif ( $pageCountChange ) {
1838                         # Added redirect
1839                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
1840                 } else{
1841                         $u = false;
1842                 }
1843                 if ( $u ) {
1844                         $u->doUpdate();
1845                 }
1846
1847                 global $wgUser;
1848                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
1849                 return true;
1850         }
1851
1852         /**
1853          * Move page to a title which is at present a redirect to the
1854          * source page
1855          *
1856          * @param Title &$nt the page to move to, which should currently
1857          *      be a redirect
1858          * @private
1859          */
1860         function moveOverExistingRedirect( &$nt, $reason = '' ) {
1861                 global $wgUseSquid;
1862                 $fname = 'Title::moveOverExistingRedirect';
1863                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
1864
1865                 if ( $reason ) {
1866                         $comment .= ": $reason";
1867                 }
1868
1869                 $now = wfTimestampNow();
1870                 $rand = wfRandom();
1871                 $newid = $nt->getArticleID();
1872                 $oldid = $this->getArticleID();
1873                 $dbw =& wfGetDB( DB_MASTER );
1874                 $linkCache =& LinkCache::singleton();
1875
1876                 # Delete the old redirect. We don't save it to history since
1877                 # by definition if we've got here it's rather uninteresting.
1878                 # We have to remove it so that the next step doesn't trigger
1879                 # a conflict on the unique namespace+title index...
1880                 $dbw->delete( 'page', array( 'page_id' => $newid ), $fname );
1881
1882                 # Save a null revision in the page's history notifying of the move
1883                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
1884                 $nullRevId = $nullRevision->insertOn( $dbw );
1885
1886                 # Change the name of the target page:
1887                 $dbw->update( 'page',
1888                         /* SET */ array(
1889                                 'page_touched'   => $dbw->timestamp($now),
1890                                 'page_namespace' => $nt->getNamespace(),
1891                                 'page_title'     => $nt->getDBkey(),
1892                                 'page_latest'    => $nullRevId,
1893                         ),
1894                         /* WHERE */ array( 'page_id' => $oldid ),
1895                         $fname
1896                 );
1897                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
1898
1899                 # Recreate the redirect, this time in the other direction.
1900                 $mwRedir = MagicWord::get( 'redirect' );
1901                 $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
1902                 $redirectArticle = new Article( $this );
1903                 $newid = $redirectArticle->insertOn( $dbw );
1904                 $redirectRevision = new Revision( array(
1905                         'page'    => $newid,
1906                         'comment' => $comment,
1907                         'text'    => $redirectText ) );
1908                 $revid = $redirectRevision->insertOn( $dbw );
1909                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
1910                 $linkCache->clearLink( $this->getPrefixedDBkey() );
1911
1912                 # Log the move
1913                 $log = new LogPage( 'move' );
1914                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText() ) );
1915
1916                 # Now, we record the link from the redirect to the new title.
1917                 # It should have no other outgoing links...
1918                 $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), $fname );
1919                 $dbw->insert( 'pagelinks',
1920                         array(
1921                                 'pl_from'      => $newid,
1922                                 'pl_namespace' => $nt->getNamespace(),
1923                                 'pl_title'     => $nt->getDbKey() ),
1924                         $fname );
1925
1926                 # Purge squid
1927                 if ( $wgUseSquid ) {
1928                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
1929                         $u = new SquidUpdate( $urls );
1930                         $u->doUpdate();
1931                 }
1932         }
1933
1934         /**
1935          * Move page to non-existing title.
1936          * @param Title &$nt the new Title
1937          * @private
1938          */
1939         function moveToNewTitle( &$nt, $reason = '' ) {
1940                 global $wgUseSquid;
1941                 $fname = 'MovePageForm::moveToNewTitle';
1942                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
1943                 if ( $reason ) {
1944                         $comment .= ": $reason";
1945                 }
1946
1947                 $newid = $nt->getArticleID();
1948                 $oldid = $this->getArticleID();
1949                 $dbw =& wfGetDB( DB_MASTER );
1950                 $now = $dbw->timestamp();
1951                 $rand = wfRandom();
1952                 $linkCache =& LinkCache::singleton();
1953
1954                 # Save a null revision in the page's history notifying of the move
1955                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
1956                 $nullRevId = $nullRevision->insertOn( $dbw );
1957
1958                 # Rename cur entry
1959                 $dbw->update( 'page',
1960                         /* SET */ array(
1961                                 'page_touched'   => $now,
1962                                 'page_namespace' => $nt->getNamespace(),
1963                                 'page_title'     => $nt->getDBkey(),
1964                                 'page_latest'    => $nullRevId,
1965                         ),
1966                         /* WHERE */ array( 'page_id' => $oldid ),
1967                         $fname
1968                 );
1969
1970                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
1971
1972                 # Insert redirect
1973                 $mwRedir = MagicWord::get( 'redirect' );
1974                 $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
1975                 $redirectArticle = new Article( $this );
1976                 $newid = $redirectArticle->insertOn( $dbw );
1977                 $redirectRevision = new Revision( array(
1978                         'page'    => $newid,
1979                         'comment' => $comment,
1980                         'text'    => $redirectText ) );
1981                 $revid = $redirectRevision->insertOn( $dbw );
1982                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
1983                 $linkCache->clearLink( $this->getPrefixedDBkey() );
1984
1985                 # Log the move
1986                 $log = new LogPage( 'move' );
1987                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText()) );
1988
1989                 # Purge caches as per article creation
1990                 Article::onArticleCreate( $nt );
1991
1992                 # Record the just-created redirect's linking to the page
1993                 $dbw->insert( 'pagelinks',
1994                         array(
1995                                 'pl_from'      => $newid,
1996                                 'pl_namespace' => $nt->getNamespace(),
1997                                 'pl_title'     => $nt->getDBkey() ),
1998                         $fname );
1999
2000                 # Purge old title from squid
2001                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
2002                 $this->purgeSquid();
2003         }
2004
2005         /**
2006          * Checks if $this can be moved to a given Title
2007          * - Selects for update, so don't call it unless you mean business
2008          *
2009          * @param Title &$nt the new title to check
2010          * @access public
2011          */
2012         function isValidMoveTarget( $nt ) {
2013
2014                 $fname = 'Title::isValidMoveTarget';
2015                 $dbw =& wfGetDB( DB_MASTER );
2016
2017                 # Is it a redirect?
2018                 $id  = $nt->getArticleID();
2019                 $obj = $dbw->selectRow( array( 'page', 'revision', 'text'),
2020                         array( 'page_is_redirect','old_text','old_flags' ),
2021                         array( 'page_id' => $id, 'page_latest=rev_id', 'rev_text_id=old_id' ),
2022                         $fname, 'FOR UPDATE' );
2023
2024                 if ( !$obj || 0 == $obj->page_is_redirect ) {
2025                         # Not a redirect
2026                         wfDebug( __METHOD__ . ": not a redirect\n" );
2027                         return false;
2028                 }
2029                 $text = Revision::getRevisionText( $obj );
2030
2031                 # Does the redirect point to the source?
2032                 # Or is it a broken self-redirect, usually caused by namespace collisions?
2033                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
2034                         $redirTitle = Title::newFromText( $m[1] );
2035                         if( !is_object( $redirTitle ) ||
2036                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
2037                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
2038                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
2039                                 return false;
2040                         }
2041                 } else {
2042                         # Fail safe
2043                         wfDebug( __METHOD__ . ": failsafe\n" );
2044                         return false;
2045                 }
2046
2047                 # Does the article have a history?
2048                 $row = $dbw->selectRow( array( 'page', 'revision'),
2049                         array( 'rev_id' ),
2050                         array( 'page_namespace' => $nt->getNamespace(),
2051                                 'page_title' => $nt->getDBkey(),
2052                                 'page_id=rev_page AND page_latest != rev_id'
2053                         ), $fname, 'FOR UPDATE'
2054                 );
2055
2056                 # Return true if there was no history
2057                 return $row === false;
2058         }
2059
2060         /**
2061          * Create a redirect; fails if the title already exists; does
2062          * not notify RC
2063          *
2064          * @param Title $dest the destination of the redirect
2065          * @param string $comment the comment string describing the move
2066          * @return bool true on success
2067          * @access public
2068          */
2069         function createRedirect( $dest, $comment ) {
2070                 if ( $this->getArticleID() ) {
2071                         return false;
2072                 }
2073
2074                 $fname = 'Title::createRedirect';
2075                 $dbw =& wfGetDB( DB_MASTER );
2076
2077                 $article = new Article( $this );
2078                 $newid = $article->insertOn( $dbw );
2079                 $revision = new Revision( array(
2080                         'page'      => $newid,
2081                         'comment'   => $comment,
2082                         'text'      => "#REDIRECT [[" . $dest->getPrefixedText() . "]]\n",
2083                         ) );
2084                 $revisionId = $revision->insertOn( $dbw );
2085                 $article->updateRevisionOn( $dbw, $revision, 0 );
2086
2087                 # Link table
2088                 $dbw->insert( 'pagelinks',
2089                         array(
2090                                 'pl_from'      => $newid,
2091                                 'pl_namespace' => $dest->getNamespace(),
2092                                 'pl_title'     => $dest->getDbKey()
2093                         ), $fname
2094                 );
2095
2096                 Article::onArticleCreate( $this );
2097                 return true;
2098         }
2099
2100         /**
2101          * Get categories to which this Title belongs and return an array of
2102          * categories' names.
2103          *
2104          * @return array an array of parents in the form:
2105          *      $parent => $currentarticle
2106          * @access public
2107          */
2108         function getParentCategories() {
2109                 global $wgContLang;
2110
2111                 $titlekey = $this->getArticleId();
2112                 $dbr =& wfGetDB( DB_SLAVE );
2113                 $categorylinks = $dbr->tableName( 'categorylinks' );
2114
2115                 # NEW SQL
2116                 $sql = "SELECT * FROM $categorylinks"
2117                      ." WHERE cl_from='$titlekey'"
2118                          ." AND cl_from <> '0'"
2119                          ." ORDER BY cl_sortkey";
2120
2121                 $res = $dbr->query ( $sql ) ;
2122
2123                 if($dbr->numRows($res) > 0) {
2124                         while ( $x = $dbr->fetchObject ( $res ) )
2125                                 //$data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to);
2126                                 $data[$wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to] = $this->getFullText();
2127                         $dbr->freeResult ( $res ) ;
2128                 } else {
2129                         $data = '';
2130                 }
2131                 return $data;
2132         }
2133
2134         /**
2135          * Get a tree of parent categories
2136          * @param array $children an array with the children in the keys, to check for circular refs
2137          * @return array
2138          * @access public
2139          */
2140         function getParentCategoryTree( $children = array() ) {
2141                 $parents = $this->getParentCategories();
2142
2143                 if($parents != '') {
2144                         foreach($parents as $parent => $current) {
2145                                 if ( array_key_exists( $parent, $children ) ) {
2146                                         # Circular reference
2147                                         $stack[$parent] = array();
2148                                 } else {
2149                                         $nt = Title::newFromText($parent);
2150                                         $stack[$parent] = $nt->getParentCategoryTree( $children + array($parent => 1) );
2151                                 }
2152                         }
2153                         return $stack;
2154                 } else {
2155                         return array();
2156                 }
2157         }
2158
2159
2160         /**
2161          * Get an associative array for selecting this title from
2162          * the "page" table
2163          *
2164          * @return array
2165          * @access public
2166          */
2167         function pageCond() {
2168                 return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
2169         }
2170
2171         /**
2172          * Get the revision ID of the previous revision
2173          *
2174          * @param integer $revision  Revision ID. Get the revision that was before this one.
2175          * @return interger $oldrevision|false
2176          */
2177         function getPreviousRevisionID( $revision ) {
2178                 $dbr =& wfGetDB( DB_SLAVE );
2179                 return $dbr->selectField( 'revision', 'rev_id',
2180                         'rev_page=' . intval( $this->getArticleId() ) .
2181                         ' AND rev_id<' . intval( $revision ) . ' ORDER BY rev_id DESC' );
2182         }
2183
2184         /**
2185          * Get the revision ID of the next revision
2186          *
2187          * @param integer $revision  Revision ID. Get the revision that was after this one.
2188          * @return interger $oldrevision|false
2189          */
2190         function getNextRevisionID( $revision ) {
2191                 $dbr =& wfGetDB( DB_SLAVE );
2192                 return $dbr->selectField( 'revision', 'rev_id',
2193                         'rev_page=' . intval( $this->getArticleId() ) .
2194                         ' AND rev_id>' . intval( $revision ) . ' ORDER BY rev_id' );
2195         }
2196
2197         /**
2198          * Compare with another title.
2199          *
2200          * @param Title $title
2201          * @return bool
2202          */
2203         function equals( $title ) {
2204                 // Note: === is necessary for proper matching of number-like titles.
2205                 return $this->getInterwiki() === $title->getInterwiki()
2206                         && $this->getNamespace() == $title->getNamespace()
2207                         && $this->getDbkey() === $title->getDbkey();
2208         }
2209
2210         /**
2211          * Check if page exists
2212          * @return bool
2213          */
2214         function exists() {
2215                 return $this->getArticleId() != 0;
2216         }
2217
2218         /**
2219          * Should a link should be displayed as a known link, just based on its title?
2220          *
2221          * Currently, a self-link with a fragment and special pages are in
2222          * this category. Special pages never exist in the database.
2223          */
2224         function isAlwaysKnown() {
2225                 return  $this->isExternal() || ( 0 == $this->mNamespace && "" == $this->mDbkeyform )
2226                   || NS_SPECIAL == $this->mNamespace;
2227         }
2228
2229         /**
2230          * Update page_touched timestamps and send squid purge messages for
2231          * pages linking to this title. May be sent to the job queue depending
2232          * on the number of links. Typically called on create and delete.
2233          */
2234         function touchLinks() {
2235                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
2236                 $u->doUpdate();
2237
2238                 if ( $this->getNamespace() == NS_CATEGORY ) {
2239                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
2240                         $u->doUpdate();
2241                 }
2242         }
2243
2244         function trackbackURL() {
2245                 global $wgTitle, $wgScriptPath, $wgServer;
2246
2247                 return "$wgServer$wgScriptPath/trackback.php?article="
2248                         . htmlspecialchars(urlencode($wgTitle->getPrefixedDBkey()));
2249         }
2250
2251         function trackbackRDF() {
2252                 $url = htmlspecialchars($this->getFullURL());
2253                 $title = htmlspecialchars($this->getText());
2254                 $tburl = $this->trackbackURL();
2255
2256                 return "
2257 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
2258          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
2259          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
2260 <rdf:Description
2261    rdf:about=\"$url\"
2262    dc:identifier=\"$url\"
2263    dc:title=\"$title\"
2264    trackback:ping=\"$tburl\" />
2265 </rdf:RDF>";
2266         }
2267
2268         /**
2269          * Generate strings used for xml 'id' names in monobook tabs
2270          * @return string
2271          */
2272         function getNamespaceKey() {
2273                 switch ($this->getNamespace()) {
2274                         case NS_MAIN:
2275                         case NS_TALK:
2276                                 return 'nstab-main';
2277                         case NS_USER:
2278                         case NS_USER_TALK:
2279                                 return 'nstab-user';
2280                         case NS_MEDIA:
2281                                 return 'nstab-media';
2282                         case NS_SPECIAL:
2283                                 return 'nstab-special';
2284                         case NS_PROJECT:
2285                         case NS_PROJECT_TALK:
2286                                 return 'nstab-project';
2287                         case NS_IMAGE:
2288                         case NS_IMAGE_TALK:
2289                                 return 'nstab-image';
2290                         case NS_MEDIAWIKI:
2291                         case NS_MEDIAWIKI_TALK:
2292                                 return 'nstab-mediawiki';
2293                         case NS_TEMPLATE:
2294                         case NS_TEMPLATE_TALK:
2295                                 return 'nstab-template';
2296                         case NS_HELP:
2297                         case NS_HELP_TALK:
2298                                 return 'nstab-help';
2299                         case NS_CATEGORY:
2300                         case NS_CATEGORY_TALK:
2301                                 return 'nstab-category';
2302                         default:
2303                                 return 'nstab-' . strtolower( $this->getSubjectNsText() );
2304                 }
2305         }
2306 }
2307 ?>