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 $wgTitleInterwikiCache = array();
  12 $wgTitleCache = array();
  13
  14 define ( 'GAID_FOR_UPDATE', 1 );
  15
  16 # Title::newFromTitle maintains a cache to avoid
  17 # expensive re-normalization of commonly used titles.
  18 # On a batch operation this can become a memory leak
  19 # if not bounded. After hitting this many titles,
  20 # reset the cache.
  21 define( 'MW_TITLECACHE_MAX', 1000 );
  22
  23 /**
  24  * Title class
  25  * - Represents a title, which may contain an interwiki designation or namespace
  26  * - Can fetch various kinds of data from the database, albeit inefficiently.
  27  *
  28  * @package MediaWiki
  29  */
  30 class Title {
  31         /**
  32          * All member variables should be considered private
  33          * Please use the accessor functions
  34          */
  35
  36          /**#@+
  37          * @access private
  38          */
  39
  40         var $mTextform;           # Text form (spaces not underscores) of the main part
  41         var $mUrlform;            # URL-encoded form of the main part
  42         var $mDbkeyform;          # Main part with underscores
  43         var $mNamespace;          # Namespace index, i.e. one of the NS_xxxx constants
  44         var $mInterwiki;          # Interwiki prefix (or null string)
  45         var $mFragment;           # Title fragment (i.e. the bit after the #)
  46         var $mArticleID;          # Article ID, fetched from the link cache on demand
  47         var $mLatestID;         # ID of most recent revision
  48         var $mRestrictions;       # Array of groups allowed to edit this article
  49                                 # Only null or "sysop" are supported
  50         var $mRestrictionsLoaded; # Boolean for initialisation on demand
  51         var $mPrefixedText;       # Text form including namespace/interwiki, initialised on demand
  52         var $mDefaultNamespace;   # Namespace index when there is no namespace
  53                             # Zero except in {{transclusion}} tags
  54         var $mWatched;      # Is $wgUser watching this page? NULL if unfilled, accessed through userIsWatching()
  55         /**#@-*/
  56
  57
  58         /**
  59          * Constructor
  60          * @access private
  61          */
  62         /* private */ function Title() {
  63                 $this->mInterwiki = $this->mUrlform =
  64                 $this->mTextform = $this->mDbkeyform = '';
  65                 $this->mArticleID = -1;
  66                 $this->mNamespace = NS_MAIN;
  67                 $this->mRestrictionsLoaded = false;
  68                 $this->mRestrictions = array();
  69                 # Dont change the following, NS_MAIN is hardcoded in several place
  70                 # See bug #696
  71                 $this->mDefaultNamespace = NS_MAIN;
  72                 $this->mWatched = NULL;
  73                 $this->mLatestID = false;
  74         }
  75
  76         /**
  77          * Create a new Title from a prefixed DB key
  78          * @param string $key The database key, which has underscores
  79          *      instead of spaces, possibly including namespace and
  80          *      interwiki prefixes
  81          * @return Title the new object, or NULL on an error
  82          * @static
  83          * @access public
  84          */
  85         /* static */ function newFromDBkey( $key ) {
  86                 $t = new Title();
  87                 $t->mDbkeyform = $key;
  88                 if( $t->secureAndSplit() )
  89                         return $t;
  90                 else
  91                         return NULL;
  92         }
  93
  94         /**
  95          * Create a new Title from text, such as what one would
  96          * find in a link. Decodes any HTML entities in the text.
  97          *
  98          * @param string $text the link text; spaces, prefixes,
  99          *      and an initial ':' indicating the main namespace
 100          *      are accepted
 101          * @param int $defaultNamespace the namespace to use if
 102          *      none is specified by a prefix
 103          * @return Title the new object, or NULL on an error
 104          * @static
 105          * @access public
 106          */
 107         function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 108                 global $wgTitleCache;
 109                 $fname = 'Title::newFromText';
 110
 111                 if( is_object( $text ) ) {
 112                         wfDebugDieBacktrace( 'Title::newFromText given an object' );
 113                 }
 114
 115                 /**
 116                  * Wiki pages often contain multiple links to the same page.
 117                  * Title normalization and parsing can become expensive on
 118                  * pages with many links, so we can save a little time by
 119                  * caching them.
 120                  *
 121                  * In theory these are value objects and won't get changed...
 122                  */
 123                 if( $defaultNamespace == NS_MAIN && isset( $wgTitleCache[$text] ) ) {
 124                         return $wgTitleCache[$text];
 125                 }
 126
 127                 /**
 128                  * Convert things like &eacute; &#257; or &#x3017; into real text...
 129                  */
 130                 $filteredText = Sanitizer::decodeCharReferences( $text );
 131
 132                 $t =& new Title();
 133                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 134                 $t->mDefaultNamespace = $defaultNamespace;
 135
 136                 static $cachedcount = 0 ;
 137                 if( $t->secureAndSplit() ) {
 138                         if( $defaultNamespace == NS_MAIN ) {
 139                                 if( $cachedcount >= MW_TITLECACHE_MAX ) {
 140                                         # Avoid memory leaks on mass operations...
 141                                         $wgTitleCache = array();
 142                                         $cachedcount=0;
 143                                 }
 144                                 $cachedcount++;
 145                                 $wgTitleCache[$text] =& $t;
 146                         }
 147                         return $t;
 148                 } else {
 149                         $ret = NULL;
 150                         return $ret;
 151                 }
 152         }
 153
 154         /**
 155          * Create a new Title from URL-encoded text. Ensures that
 156          * the given title's length does not exceed the maximum.
 157          * @param string $url the title, as might be taken from a URL
 158          * @return Title the new object, or NULL on an error
 159          * @static
 160          * @access public
 161          */
 162         function newFromURL( $url ) {
 163                 global $wgLegalTitleChars;
 164                 $t = new Title();
 165
 166                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 167                 # but some URLs used it as a space replacement and they still come
 168                 # from some external search tools.
 169                 if ( strpos( $wgLegalTitleChars, '+' ) === false ) {
 170                         $url = str_replace( '+', ' ', $url );
 171                 }
 172
 173                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 174                 if( $t->secureAndSplit() ) {
 175                         return $t;
 176                 } else {
 177                         return NULL;
 178                 }
 179         }
 180
 181         /**
 182          * Create a new Title from an article ID
 183          *
 184          * @todo This is inefficiently implemented, the page row is requested
 185          *       but not used for anything else
 186          *
 187          * @param int $id the page_id corresponding to the Title to create
 188          * @return Title the new object, or NULL on an error
 189          * @access public
 190          * @static
 191          */
 192         function newFromID( $id ) {
 193                 $fname = 'Title::newFromID';
 194                 $dbr =& wfGetDB( DB_SLAVE );
 195                 $row = $dbr->selectRow( 'page', array( 'page_namespace', 'page_title' ),
 196                         array( 'page_id' => $id ), $fname );
 197                 if ( $row !== false ) {
 198                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 199                 } else {
 200                         $title = NULL;
 201                 }
 202                 return $title;
 203         }
 204
 205         /**
 206          * Create a new Title from a namespace index and a DB key.
 207          * It's assumed that $ns and $title are *valid*, for instance when
 208          * they came directly from the database or a special page name.
 209          * For convenience, spaces are converted to underscores so that
 210          * eg user_text fields can be used directly.
 211          *
 212          * @param int $ns the namespace of the article
 213          * @param string $title the unprefixed database key form
 214          * @return Title the new object
 215          * @static
 216          * @access public
 217          */
 218         function &makeTitle( $ns, $title ) {
 219                 $t =& new Title();
 220                 $t->mInterwiki = '';
 221                 $t->mFragment = '';
 222                 $t->mNamespace = intval( $ns );
 223                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 224                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 225                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 226                 $t->mTextform = str_replace( '_', ' ', $title );
 227                 return $t;
 228         }
 229
 230         /**
 231          * Create a new Title frrom a namespace index and a DB key.
 232          * The parameters will be checked for validity, which is a bit slower
 233          * than makeTitle() but safer for user-provided data.
 234          *
 235          * @param int $ns the namespace of the article
 236          * @param string $title the database key form
 237          * @return Title the new object, or NULL on an error
 238          * @static
 239          * @access public
 240          */
 241         function makeTitleSafe( $ns, $title ) {
 242                 $t = new Title();
 243                 $t->mDbkeyform = Title::makeName( $ns, $title );
 244                 if( $t->secureAndSplit() ) {
 245                         return $t;
 246                 } else {
 247                         return NULL;
 248                 }
 249         }
 250
 251         /**
 252          * Create a new Title for the Main Page
 253          *
 254          * @static
 255          * @return Title the new object
 256          * @access public
 257          */
 258         function newMainPage() {
 259                 return Title::newFromText( wfMsgForContent( 'mainpage' ) );
 260         }
 261
 262         /**
 263          * Create a new Title for a redirect
 264          * @param string $text the redirect title text
 265          * @return Title the new object, or NULL if the text is not a
 266          *      valid redirect
 267          * @static
 268          * @access public
 269          */
 270         function newFromRedirect( $text ) {
 271                 global $wgMwRedir;
 272                 $rt = NULL;
 273                 if ( $wgMwRedir->matchStart( $text ) ) {
 274                         if ( preg_match( '/\[{2}(.*?)(?:\||\]{2})/', $text, $m ) ) {
 275                                 # categories are escaped using : for example one can enter:
 276                                 # #REDIRECT [[:Category:Music]]. Need to remove it.
 277                                 if ( substr($m[1],0,1) == ':') {
 278                                         # We don't want to keep the ':'
 279                                         $m[1] = substr( $m[1], 1 );
 280                                 }
 281
 282                                 $rt = Title::newFromText( $m[1] );
 283                                 # Disallow redirects to Special:Userlogout
 284                                 if ( !is_null($rt) && $rt->getNamespace() == NS_SPECIAL && preg_match( '/^Userlogout/i', $rt->getText() ) ) {
 285                                         $rt = NULL;
 286                                 }
 287                         }
 288                 }
 289                 return $rt;
 290         }
 291
 292 #----------------------------------------------------------------------------
 293 #       Static functions
 294 #----------------------------------------------------------------------------
 295
 296         /**
 297          * Get the prefixed DB key associated with an ID
 298          * @param int $id the page_id of the article
 299          * @return Title an object representing the article, or NULL
 300          *      if no such article was found
 301          * @static
 302          * @access public
 303          */
 304         function nameOf( $id ) {
 305                 $fname = 'Title::nameOf';
 306                 $dbr =& wfGetDB( DB_SLAVE );
 307
 308                 $s = $dbr->selectRow( 'page', array( 'page_namespace','page_title' ),  array( 'page_id' => $id ), $fname );
 309                 if ( $s === false ) { return NULL; }
 310
 311                 $n = Title::makeName( $s->page_namespace, $s->page_title );
 312                 return $n;
 313         }
 314
 315         /**
 316          * Get a regex character class describing the legal characters in a link
 317          * @return string the list of characters, not delimited
 318          * @static
 319          * @access public
 320          */
 321         function legalChars() {
 322                 global $wgLegalTitleChars;
 323                 return $wgLegalTitleChars;
 324         }
 325
 326         /**
 327          * Get a string representation of a title suitable for
 328          * including in a search index
 329          *
 330          * @param int $ns a namespace index
 331          * @param string $title text-form main part
 332          * @return string a stripped-down title string ready for the
 333          *      search index
 334          */
 335         /* static */ function indexTitle( $ns, $title ) {
 336                 global $wgContLang;
 337                 require_once( 'SearchEngine.php' );
 338
 339                 $lc = SearchEngine::legalSearchChars() . '&#;';
 340                 $t = $wgContLang->stripForSearch( $title );
 341                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 342                 $t = strtolower( $t );
 343
 344                 # Handle 's, s'
 345                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 346                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 347
 348                 $t = preg_replace( "/\\s+/", ' ', $t );
 349
 350                 if ( $ns == NS_IMAGE ) {
 351                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 352                 }
 353                 return trim( $t );
 354         }
 355
 356         /*
 357          * Make a prefixed DB key from a DB key and a namespace index
 358          * @param int $ns numerical representation of the namespace
 359          * @param string $title the DB key form the title
 360          * @return string the prefixed form of the title
 361          */
 362         /* static */ function makeName( $ns, $title ) {
 363                 global $wgContLang;
 364
 365                 $n = $wgContLang->getNsText( $ns );
 366                 return $n == '' ? $title : "$n:$title";
 367         }
 368
 369         /**
 370          * Returns the URL associated with an interwiki prefix
 371          * @param string $key the interwiki prefix (e.g. "MeatBall")
 372          * @return the associated URL, containing "$1", which should be
 373          *      replaced by an article title
 374          * @static (arguably)
 375          * @access public
 376          */
 377         function getInterwikiLink( $key )  {
 378                 global $wgMemc, $wgDBname, $wgInterwikiExpiry, $wgTitleInterwikiCache;
 379                 global $wgInterwikiCache;
 380                 $fname = 'Title::getInterwikiLink';
 381
 382                 $key = strtolower( $key );
 383
 384                 $k = $wgDBname.':interwiki:'.$key;
 385                 if( array_key_exists( $k, $wgTitleInterwikiCache ) ) {
 386                         return $wgTitleInterwikiCache[$k]->iw_url;
 387                 }
 388
 389                 if ($wgInterwikiCache) {
 390                         return Title::getInterwikiCached( $key );
 391                 }
 392
 393                 $s = $wgMemc->get( $k );
 394                 # Ignore old keys with no iw_local
 395                 if( $s && isset( $s->iw_local ) && isset($s->iw_trans)) {
 396                         $wgTitleInterwikiCache[$k] = $s;
 397                         return $s->iw_url;
 398                 }
 399
 400                 $dbr =& wfGetDB( DB_SLAVE );
 401                 $res = $dbr->select( 'interwiki',
 402                         array( 'iw_url', 'iw_local', 'iw_trans' ),
 403                         array( 'iw_prefix' => $key ), $fname );
 404                 if( !$res ) {
 405                         return '';
 406                 }
 407
 408                 $s = $dbr->fetchObject( $res );
 409                 if( !$s ) {
 410                         # Cache non-existence: create a blank object and save it to memcached
 411                         $s = (object)false;
 412                         $s->iw_url = '';
 413                         $s->iw_local = 0;
 414                         $s->iw_trans = 0;
 415                 }
 416                 $wgMemc->set( $k, $s, $wgInterwikiExpiry );
 417                 $wgTitleInterwikiCache[$k] = $s;
 418
 419                 return $s->iw_url;
 420         }
 421
 422         /**
 423          * Fetch interwiki prefix data from local cache in constant database
 424          *
 425          * More logic is explained in DefaultSettings
 426          *
 427          * @return string URL of interwiki site
 428          * @access public
 429          */
 430         function getInterwikiCached( $key ) {
 431                 global $wgDBname, $wgInterwikiCache, $wgInterwikiScopes, $wgInterwikiFallbackSite;
 432                 global $wgTitleInterwikiCache;
 433                 static $db, $site;
 434
 435                 if (!$db)
 436                         $db=dba_open($wgInterwikiCache,'r','cdb');
 437                 /* Resolve site name */
 438                 if ($wgInterwikiScopes>=3 and !$site) {
 439                         $site = dba_fetch("__sites:{$wgDBname}", $db);
 440                         if ($site=="")
 441                                 $site = $wgInterwikiFallbackSite;
 442                 }
 443                 $value = dba_fetch("{$wgDBname}:{$key}", $db);
 444                 if ($value=='' and $wgInterwikiScopes>=3) {
 445                         /* try site-level */
 446                         $value = dba_fetch("_{$site}:{$key}", $db);
 447                 }
 448                 if ($value=='' and $wgInterwikiScopes>=2) {
 449                         /* try globals */
 450                         $value = dba_fetch("__global:{$key}", $db);
 451                 }
 452                 if ($value=='undef')
 453                         $value='';
 454                 $s = (object)false;
 455                 $s->iw_url = '';
 456                 $s->iw_local = 0;
 457                 $s->iw_trans = 0;
 458                 if ($value!='') {
 459                         list($local,$url)=explode(' ',$value,2);
 460                         $s->iw_url=$url;
 461                         $s->iw_local=(int)$local;
 462                 }
 463                 $wgTitleInterwikiCache[$wgDBname.':interwiki:'.$key] = $s;
 464                 return $s->iw_url;
 465         }
 466         /**
 467          * Determine whether the object refers to a page within
 468          * this project.
 469          *
 470          * @return bool TRUE if this is an in-project interwiki link
 471          *      or a wikilink, FALSE otherwise
 472          * @access public
 473          */
 474         function isLocal() {
 475                 global $wgTitleInterwikiCache, $wgDBname;
 476
 477                 if ( $this->mInterwiki != '' ) {
 478                         # Make sure key is loaded into cache
 479                         $this->getInterwikiLink( $this->mInterwiki );
 480                         $k = $wgDBname.':interwiki:' . $this->mInterwiki;
 481                         return (bool)($wgTitleInterwikiCache[$k]->iw_local);
 482                 } else {
 483                         return true;
 484                 }
 485         }
 486
 487         /**
 488          * Determine whether the object refers to a page within
 489          * this project and is transcludable.
 490          *
 491          * @return bool TRUE if this is transcludable
 492          * @access public
 493          */
 494         function isTrans() {
 495                 global $wgTitleInterwikiCache, $wgDBname;
 496
 497                 if ($this->mInterwiki == '')
 498                         return false;
 499                 # Make sure key is loaded into cache
 500                 $this->getInterwikiLink( $this->mInterwiki );
 501                 $k = $wgDBname.':interwiki:' . $this->mInterwiki;
 502                 return (bool)($wgTitleInterwikiCache[$k]->iw_trans);
 503         }
 504
 505         /**
 506          * Update the page_touched field for an array of title objects
 507          * @todo Inefficient unless the IDs are already loaded into the
 508          *      link cache
 509          * @param array $titles an array of Title objects to be touched
 510          * @param string $timestamp the timestamp to use instead of the
 511          *      default current time
 512          * @static
 513          * @access public
 514          */
 515         function touchArray( $titles, $timestamp = '' ) {
 516
 517                 if ( count( $titles ) == 0 ) {
 518                         return;
 519                 }
 520                 $dbw =& wfGetDB( DB_MASTER );
 521                 if ( $timestamp == '' ) {
 522                         $timestamp = $dbw->timestamp();
 523                 }
 524                 /*
 525                 $page = $dbw->tableName( 'page' );
 526                 $sql = "UPDATE $page SET page_touched='{$timestamp}' WHERE page_id IN (";
 527                 $first = true;
 528
 529                 foreach ( $titles as $title ) {
 530                         if ( $wgUseFileCache ) {
 531                                 $cm = new CacheManager($title);
 532                                 @unlink($cm->fileCacheName());
 533                         }
 534
 535                         if ( ! $first ) {
 536                                 $sql .= ',';
 537                         }
 538                         $first = false;
 539                         $sql .= $title->getArticleID();
 540                 }
 541                 $sql .= ')';
 542                 if ( ! $first ) {
 543                         $dbw->query( $sql, 'Title::touchArray' );
 544                 }
 545                 */
 546                 // hack hack hack -- brion 2005-07-11. this was unfriendly to db.
 547                 // do them in small chunks:
 548                 $fname = 'Title::touchArray';
 549                 foreach( $titles as $title ) {
 550                         $dbw->update( 'page',
 551                                 array( 'page_touched' => $timestamp ),
 552                                 array(
 553                                         'page_namespace' => $title->getNamespace(),
 554                                         'page_title'     => $title->getDBkey() ),
 555                                 $fname );
 556                 }
 557         }
 558
 559 #----------------------------------------------------------------------------
 560 #       Other stuff
 561 #----------------------------------------------------------------------------
 562
 563         /** Simple accessors */
 564         /**
 565          * Get the text form (spaces not underscores) of the main part
 566          * @return string
 567          * @access public
 568          */
 569         function getText() { return $this->mTextform; }
 570         /**
 571          * Get the URL-encoded form of the main part
 572          * @return string
 573          * @access public
 574          */
 575         function getPartialURL() { return $this->mUrlform; }
 576         /**
 577          * Get the main part with underscores
 578          * @return string
 579          * @access public
 580          */
 581         function getDBkey() { return $this->mDbkeyform; }
 582         /**
 583          * Get the namespace index, i.e. one of the NS_xxxx constants
 584          * @return int
 585          * @access public
 586          */
 587         function getNamespace() { return $this->mNamespace; }
 588         /**
 589          * Get the namespace text
 590          * @return string
 591          * @access public
 592          */
 593         function getNsText() {
 594                 global $wgContLang;
 595                 return $wgContLang->getNsText( $this->mNamespace );
 596         }
 597         /**
 598          * Get the namespace text of the subject (rather than talk) page
 599          * @return string
 600          * @access public
 601          */
 602         function getSubjectNsText() {
 603                 global $wgContLang;
 604                 return $wgContLang->getNsText( Namespace::getSubject( $this->mNamespace ) );
 605         }
 606
 607         /**
 608          * Get the namespace text of the talk page
 609          * @return string
 610          */
 611         function getTalkNsText() {
 612                 global $wgContLang;
 613                 return( $wgContLang->getNsText( Namespace::getTalk( $this->mNamespace ) ) );
 614         }
 615
 616         /**
 617          * Could this title have a corresponding talk page?
 618          * @return bool
 619          */
 620         function canTalk() {
 621                 return( Namespace::canTalk( $this->mNamespace ) );
 622         }
 623
 624         /**
 625          * Get the interwiki prefix (or null string)
 626          * @return string
 627          * @access public
 628          */
 629         function getInterwiki() { return $this->mInterwiki; }
 630         /**
 631          * Get the Title fragment (i.e. the bit after the #)
 632          * @return string
 633          * @access public
 634          */
 635         function getFragment() { return $this->mFragment; }
 636         /**
 637          * Get the default namespace index, for when there is no namespace
 638          * @return int
 639          * @access public
 640          */
 641         function getDefaultNamespace() { return $this->mDefaultNamespace; }
 642
 643         /**
 644          * Get title for search index
 645          * @return string a stripped-down title string ready for the
 646          *      search index
 647          */
 648         function getIndexTitle() {
 649                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 650         }
 651
 652         /**
 653          * Get the prefixed database key form
 654          * @return string the prefixed title, with underscores and
 655          *      any interwiki and namespace prefixes
 656          * @access public
 657          */
 658         function getPrefixedDBkey() {
 659                 $s = $this->prefix( $this->mDbkeyform );
 660                 $s = str_replace( ' ', '_', $s );
 661                 return $s;
 662         }
 663
 664         /**
 665          * Get the prefixed title with spaces.
 666          * This is the form usually used for display
 667          * @return string the prefixed title, with spaces
 668          * @access public
 669          */
 670         function getPrefixedText() {
 671                 if ( empty( $this->mPrefixedText ) ) { // FIXME: bad usage of empty() ?
 672                         $s = $this->prefix( $this->mTextform );
 673                         $s = str_replace( '_', ' ', $s );
 674                         $this->mPrefixedText = $s;
 675                 }
 676                 return $this->mPrefixedText;
 677         }
 678
 679         /**
 680          * Get the prefixed title with spaces, plus any fragment
 681          * (part beginning with '#')
 682          * @return string the prefixed title, with spaces and
 683          *      the fragment, including '#'
 684          * @access public
 685          */
 686         function getFullText() {
 687                 $text = $this->getPrefixedText();
 688                 if( '' != $this->mFragment ) {
 689                         $text .= '#' . $this->mFragment;
 690                 }
 691                 return $text;
 692         }
 693
 694         /**
 695          * Get the base name, i.e. the leftmost parts before the /
 696          * @return string Base name
 697          */
 698         function getBaseText() {
 699                 global $wgNamespacesWithSubpages;
 700                 if( isset( $wgNamespacesWithSubpages[ $this->mNamespace ] ) && $wgNamespacesWithSubpages[ $this->mNamespace ] ) {
 701                         $parts = explode( '/', $this->getText() );
 702                         # Don't discard the real title if there's no subpage involved
 703                         if( count( $parts ) > 1 )
 704                                 unset( $parts[ count( $parts ) - 1 ] );
 705                         return implode( '/', $parts );
 706                 } else {
 707                         return $this->getText();
 708                 }
 709         }
 710
 711         /**
 712          * Get the lowest-level subpage name, i.e. the rightmost part after /
 713          * @return string Subpage name
 714          */
 715         function getSubpageText() {
 716                 global $wgNamespacesWithSubpages;
 717                 if( isset( $wgNamespacesWithSubpages[ $this->mNamespace ] ) && $wgNamespacesWithSubpages[ $this->mNamespace ] ) {
 718                         $parts = explode( '/', $this->mTextform );
 719                         return( $parts[ count( $parts ) - 1 ] );
 720                 } else {
 721                         return( $this->mTextform );
 722                 }
 723         }
 724
 725         /**
 726          * Get a URL-encoded form of the subpage text
 727          * @return string URL-encoded subpage name
 728          */
 729         function getSubpageUrlForm() {
 730                 $text = $this->getSubpageText();
 731                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
 732                 $text = str_replace( '%28', '(', str_replace( '%29', ')', $text ) ); # Clean up the URL; per below, this might not be safe
 733                 return( $text );
 734         }
 735
 736         /**
 737          * Get a URL-encoded title (not an actual URL) including interwiki
 738          * @return string the URL-encoded form
 739          * @access public
 740          */
 741         function getPrefixedURL() {
 742                 $s = $this->prefix( $this->mDbkeyform );
 743                 $s = str_replace( ' ', '_', $s );
 744
 745                 $s = wfUrlencode ( $s ) ;
 746
 747                 # Cleaning up URL to make it look nice -- is this safe?
 748                 $s = str_replace( '%28', '(', $s );
 749                 $s = str_replace( '%29', ')', $s );
 750
 751                 return $s;
 752         }
 753
 754         /**
 755          * Get a real URL referring to this title, with interwiki link and
 756          * fragment
 757          *
 758          * @param string $query an optional query string, not used
 759          *      for interwiki links
 760          * @return string the URL
 761          * @access public
 762          */
 763         function getFullURL( $query = '' ) {
 764                 global $wgContLang, $wgServer, $wgRequest;
 765
 766                 if ( '' == $this->mInterwiki ) {
 767                         $url = $this->getLocalUrl( $query );
 768
 769                         // Ugly quick hack to avoid duplicate prefixes (bug 4571 etc)
 770                         // Correct fix would be to move the prepending elsewhere.
 771                         if ($wgRequest->getVal('action') != 'render') {
 772                                 $url = $wgServer . $url;
 773                         }
 774                 } else {
 775                         $baseUrl = $this->getInterwikiLink( $this->mInterwiki );
 776
 777                         $namespace = $wgContLang->getNsText( $this->mNamespace );
 778                         if ( '' != $namespace ) {
 779                                 # Can this actually happen? Interwikis shouldn't be parsed.
 780                                 $namespace .= ':';
 781                         }
 782                         $url = str_replace( '$1', $namespace . $this->mUrlform, $baseUrl );
 783                         if( $query != '' ) {
 784                                 if( false === strpos( $url, '?' ) ) {
 785                                         $url .= '?';
 786                                 } else {
 787                                         $url .= '&';
 788                                 }
 789                                 $url .= $query;
 790                         }
 791                 }
 792
 793                 # Finally, add the fragment.
 794                 if ( '' != $this->mFragment ) {
 795                         $url .= '#' . $this->mFragment;
 796                 }
 797
 798                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
 799                 return $url;
 800         }
 801
 802         /**
 803          * Get a URL with no fragment or server name.  If this page is generated
 804          * with action=render, $wgServer is prepended.
 805          * @param string $query an optional query string; if not specified,
 806          *      $wgArticlePath will be used.
 807          * @return string the URL
 808          * @access public
 809          */
 810         function getLocalURL( $query = '' ) {
 811                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
 812
 813                 if ( $this->isExternal() ) {
 814                         $url = $this->getFullURL();
 815                         if ( $query ) {
 816                                 // This is currently only used for edit section links in the
 817                                 // context of interwiki transclusion. In theory we should
 818                                 // append the query to the end of any existing query string,
 819                                 // but interwiki transclusion is already broken in that case.
 820                                 $url .= "?$query";
 821                         }
 822                 } else {
 823                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 824                         if ( $query == '' ) {
 825                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
 826                         } else {
 827                                 global $wgActionPaths;
 828                                 $url = false;
 829                                 if( !empty( $wgActionPaths ) &&
 830                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
 831                                 {
 832                                         $action = urldecode( $matches[2] );
 833                                         if( isset( $wgActionPaths[$action] ) ) {
 834                                                 $query = $matches[1];
 835                                                 if( isset( $matches[4] ) ) $query .= $matches[4];
 836                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
 837                                                 if( $query != '' ) $url .= '?' . $query;
 838                                         }
 839                                 }
 840                                 if ( $url === false ) {
 841                                         if ( $query == '-' ) {
 842                                                 $query = '';
 843                                         }
 844                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
 845                                 }
 846                         }
 847
 848                         // FIXME: this causes breakage in various places when we
 849                         // actually expected a local URL and end up with dupe prefixes.
 850                         if ($wgRequest->getVal('action') == 'render') {
 851                                 $url = $wgServer . $url;
 852                         }
 853                 }
 854                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
 855                 return $url;
 856         }
 857
 858         /**
 859          * Get an HTML-escaped version of the URL form, suitable for
 860          * using in a link, without a server name or fragment
 861          * @param string $query an optional query string
 862          * @return string the URL
 863          * @access public
 864          */
 865         function escapeLocalURL( $query = '' ) {
 866                 return htmlspecialchars( $this->getLocalURL( $query ) );
 867         }
 868
 869         /**
 870          * Get an HTML-escaped version of the URL form, suitable for
 871          * using in a link, including the server name and fragment
 872          *
 873          * @return string the URL
 874          * @param string $query an optional query string
 875          * @access public
 876          */
 877         function escapeFullURL( $query = '' ) {
 878                 return htmlspecialchars( $this->getFullURL( $query ) );
 879         }
 880
 881         /**
 882          * Get the URL form for an internal link.
 883          * - Used in various Squid-related code, in case we have a different
 884          * internal hostname for the server from the exposed one.
 885          *
 886          * @param string $query an optional query string
 887          * @return string the URL
 888          * @access public
 889          */
 890         function getInternalURL( $query = '' ) {
 891                 global $wgInternalServer;
 892                 $url = $wgInternalServer . $this->getLocalURL( $query );
 893                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
 894                 return $url;
 895         }
 896
 897         /**
 898          * Get the edit URL for this Title
 899          * @return string the URL, or a null string if this is an
 900          *      interwiki link
 901          * @access public
 902          */
 903         function getEditURL() {
 904                 if ( '' != $this->mInterwiki ) { return ''; }
 905                 $s = $this->getLocalURL( 'action=edit' );
 906
 907                 return $s;
 908         }
 909
 910         /**
 911          * Get the HTML-escaped displayable text form.
 912          * Used for the title field in <a> tags.
 913          * @return string the text, including any prefixes
 914          * @access public
 915          */
 916         function getEscapedText() {
 917                 return htmlspecialchars( $this->getPrefixedText() );
 918         }
 919
 920         /**
 921          * Is this Title interwiki?
 922          * @return boolean
 923          * @access public
 924          */
 925         function isExternal() { return ( '' != $this->mInterwiki ); }
 926
 927         /**
 928          * Is this page "semi-protected" - the *only* protection is autoconfirm?
 929          *
 930          * @param string Action to check (default: edit)
 931          * @return bool
 932          */
 933         function isSemiProtected( $action = 'edit' ) {
 934                 $restrictions = $this->getRestrictions( $action );
 935                 # We do a full compare because this could be an array
 936                 foreach( $restrictions as $restriction ) {
 937                         if( strtolower( $restriction ) != 'autoconfirmed' ) {
 938                                 return( false );
 939                         }
 940                 }
 941                 return( true );
 942         }
 943
 944         /**
 945          * Does the title correspond to a protected article?
 946          * @param string $what the action the page is protected from,
 947          *      by default checks move and edit
 948          * @return boolean
 949          * @access public
 950          */
 951         function isProtected( $action = '' ) {
 952                 global $wgRestrictionLevels;
 953                 if ( -1 == $this->mNamespace ) { return true; }
 954
 955                 if( $action == 'edit' || $action == '' ) {
 956                         $r = $this->getRestrictions( 'edit' );
 957                         foreach( $wgRestrictionLevels as $level ) {
 958                                 if( in_array( $level, $r ) && $level != '' ) {
 959                                         return( true );
 960                                 }
 961                         }
 962                 }
 963
 964                 if( $action == 'move' || $action == '' ) {
 965                         $r = $this->getRestrictions( 'move' );
 966                         foreach( $wgRestrictionLevels as $level ) {
 967                                 if( in_array( $level, $r ) && $level != '' ) {
 968                                         return( true );
 969                                 }
 970                         }
 971                 }
 972
 973                 return false;
 974         }
 975
 976         /**
 977          * Is $wgUser is watching this page?
 978          * @return boolean
 979          * @access public
 980          */
 981         function userIsWatching() {
 982                 global $wgUser;
 983
 984                 if ( is_null( $this->mWatched ) ) {
 985                         if ( -1 == $this->mNamespace || 0 == $wgUser->getID()) {
 986                                 $this->mWatched = false;
 987                         } else {
 988                                 $this->mWatched = $wgUser->isWatched( $this );
 989                         }
 990                 }
 991                 return $this->mWatched;
 992         }
 993
 994         /**
 995          * Can $wgUser perform $action this page?
 996          * @param string $action action that permission needs to be checked for
 997          * @return boolean
 998          * @access private
 999          */
1000         function userCan($action) {
1001                 $fname = 'Title::userCan';
1002                 wfProfileIn( $fname );
1003
1004                 global $wgUser;
1005
1006                 $result = null;
1007                 wfRunHooks( 'userCan', array( &$this, &$wgUser, $action, &$result ) );
1008                 if ( $result !== null ) {
1009                         wfProfileOut( $fname );
1010                         return $result;
1011                 }
1012
1013                 if( NS_SPECIAL == $this->mNamespace ) {
1014                         wfProfileOut( $fname );
1015                         return false;
1016                 }
1017                 // XXX: This is the code that prevents unprotecting a page in NS_MEDIAWIKI
1018                 // from taking effect -ævar
1019                 if( NS_MEDIAWIKI == $this->mNamespace &&
1020                     !$wgUser->isAllowed('editinterface') ) {
1021                         wfProfileOut( $fname );
1022                         return false;
1023                 }
1024
1025                 if( $this->mDbkeyform == '_' ) {
1026                         # FIXME: Is this necessary? Shouldn't be allowed anyway...
1027                         wfProfileOut( $fname );
1028                         return false;
1029                 }
1030
1031                 # protect css/js subpages of user pages
1032                 # XXX: this might be better using restrictions
1033                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssJsSubpage() from working
1034                 if( NS_USER == $this->mNamespace
1035                         && preg_match("/\\.(css|js)$/", $this->mTextform )
1036                         && !$wgUser->isAllowed('editinterface')
1037                         && !preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) ) {
1038                         wfProfileOut( $fname );
1039                         return false;
1040                 }
1041
1042                 foreach( $this->getRestrictions($action) as $right ) {
1043                         // Backwards compatibility, rewrite sysop -> protect
1044                         if ( $right == 'sysop' ) {
1045                                 $right = 'protect';
1046                         }
1047                         if( '' != $right && !$wgUser->isAllowed( $right ) ) {
1048                                 wfProfileOut( $fname );
1049                                 return false;
1050                         }
1051                 }
1052
1053                 if( $action == 'move' &&
1054                         !( $this->isMovable() && $wgUser->isAllowed( 'move' ) ) ) {
1055                         wfProfileOut( $fname );
1056                         return false;
1057                 }
1058
1059                 if( $action == 'create' ) {
1060                         if( (  $this->isTalkPage() && !$wgUser->isAllowed( 'createtalk' ) ) ||
1061                                 ( !$this->isTalkPage() && !$wgUser->isAllowed( 'createpage' ) ) ) {
1062                                 return false;
1063                         }
1064                 }
1065
1066                 wfProfileOut( $fname );
1067                 return true;
1068         }
1069
1070         /**
1071          * Can $wgUser edit this page?
1072          * @return boolean
1073          * @access public
1074          */
1075         function userCanEdit() {
1076                 return $this->userCan('edit');
1077         }
1078
1079         /**
1080          * Can $wgUser move this page?
1081          * @return boolean
1082          * @access public
1083          */
1084         function userCanMove() {
1085                 return $this->userCan('move');
1086         }
1087
1088         /**
1089          * Would anybody with sufficient privileges be able to move this page?
1090          * Some pages just aren't movable.
1091          *
1092          * @return boolean
1093          * @access public
1094          */
1095         function isMovable() {
1096                 return Namespace::isMovable( $this->getNamespace() )
1097                         && $this->getInterwiki() == '';
1098         }
1099
1100         /**
1101          * Can $wgUser read this page?
1102          * @return boolean
1103          * @access public
1104          */
1105         function userCanRead() {
1106                 global $wgUser;
1107
1108                 $result = null;
1109                 wfRunHooks( 'userCan', array( &$this, &$wgUser, 'read', &$result ) );
1110                 if ( $result !== null ) {
1111                         return $result;
1112                 }
1113
1114                 if( $wgUser->isAllowed('read') ) {
1115                         return true;
1116                 } else {
1117                         global $wgWhitelistRead;
1118
1119                         /** If anon users can create an account,
1120                             they need to reach the login page first! */
1121                         if( $wgUser->isAllowed( 'createaccount' )
1122                             && $this->getNamespace() == NS_SPECIAL
1123                             && $this->getText() == 'Userlogin' ) {
1124                                 return true;
1125                         }
1126
1127                         /** some pages are explicitly allowed */
1128                         $name = $this->getPrefixedText();
1129                         if( $wgWhitelistRead && in_array( $name, $wgWhitelistRead ) ) {
1130                                 return true;
1131                         }
1132
1133                         # Compatibility with old settings
1134                         if( $wgWhitelistRead && $this->getNamespace() == NS_MAIN ) {
1135                                 if( in_array( ':' . $name, $wgWhitelistRead ) ) {
1136                                         return true;
1137                                 }
1138                         }
1139                 }
1140                 return false;
1141         }
1142
1143         /**
1144          * Is this a talk page of some sort?
1145          * @return bool
1146          * @access public
1147          */
1148         function isTalkPage() {
1149                 return Namespace::isTalk( $this->getNamespace() );
1150         }
1151
1152         /**
1153          * Is this a .css or .js subpage of a user page?
1154          * @return bool
1155          * @access public
1156          */
1157         function isCssJsSubpage() {
1158                 return ( NS_USER == $this->mNamespace and preg_match("/\\.(css|js)$/", $this->mTextform ) );
1159         }
1160         /**
1161          * Is this a *valid* .css or .js subpage of a user page?
1162          * Check that the corresponding skin exists
1163          */
1164         function isValidCssJsSubpage() {
1165                 global $wgValidSkinNames;
1166                 return( $this->isCssJsSubpage() && array_key_exists( $this->getSkinFromCssJsSubpage(), $wgValidSkinNames ) );
1167         }
1168         /**
1169          * Trim down a .css or .js subpage title to get the corresponding skin name
1170          */
1171         function getSkinFromCssJsSubpage() {
1172                 $subpage = explode( '/', $this->mTextform );
1173                 $subpage = $subpage[ count( $subpage ) - 1 ];
1174                 return( str_replace( array( '.css', '.js' ), array( '', '' ), $subpage ) );
1175         }
1176         /**
1177          * Is this a .css subpage of a user page?
1178          * @return bool
1179          * @access public
1180          */
1181         function isCssSubpage() {
1182                 return ( NS_USER == $this->mNamespace and preg_match("/\\.css$/", $this->mTextform ) );
1183         }
1184         /**
1185          * Is this a .js subpage of a user page?
1186          * @return bool
1187          * @access public
1188          */
1189         function isJsSubpage() {
1190                 return ( NS_USER == $this->mNamespace and preg_match("/\\.js$/", $this->mTextform ) );
1191         }
1192         /**
1193          * Protect css/js subpages of user pages: can $wgUser edit
1194          * this page?
1195          *
1196          * @return boolean
1197          * @todo XXX: this might be better using restrictions
1198          * @access public
1199          */
1200         function userCanEditCssJsSubpage() {
1201                 global $wgUser;
1202                 return ( $wgUser->isAllowed('editinterface') or preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1203         }
1204
1205         /**
1206          * Loads a string into mRestrictions array
1207          * @param string $res restrictions in string format
1208          * @access public
1209          */
1210         function loadRestrictions( $res ) {
1211                 foreach( explode( ':', trim( $res ) ) as $restrict ) {
1212                         $temp = explode( '=', trim( $restrict ) );
1213                         if(count($temp) == 1) {
1214                                 // old format should be treated as edit/move restriction
1215                                 $this->mRestrictions["edit"] = explode( ',', trim( $temp[0] ) );
1216                                 $this->mRestrictions["move"] = explode( ',', trim( $temp[0] ) );
1217                         } else {
1218                                 $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
1219                         }
1220                 }
1221                 $this->mRestrictionsLoaded = true;
1222         }
1223
1224         /**
1225          * Accessor/initialisation for mRestrictions
1226          * @param string $action action that permission needs to be checked for
1227          * @return array the array of groups allowed to edit this article
1228          * @access public
1229          */
1230         function getRestrictions($action) {
1231                 $id = $this->getArticleID();
1232                 if ( 0 == $id ) { return array(); }
1233
1234                 if ( ! $this->mRestrictionsLoaded ) {
1235                         $dbr =& wfGetDB( DB_SLAVE );
1236                         $res = $dbr->selectField( 'page', 'page_restrictions', 'page_id='.$id );
1237                         $this->loadRestrictions( $res );
1238                 }
1239                 if( isset( $this->mRestrictions[$action] ) ) {
1240                         return $this->mRestrictions[$action];
1241                 }
1242                 return array();
1243         }
1244
1245         /**
1246          * Is there a version of this page in the deletion archive?
1247          * @return int the number of archived revisions
1248          * @access public
1249          */
1250         function isDeleted() {
1251                 $fname = 'Title::isDeleted';
1252                 if ( $this->getNamespace() < 0 ) {
1253                         $n = 0;
1254                 } else {
1255                         $dbr =& wfGetDB( DB_SLAVE );
1256                         $n = $dbr->selectField( 'archive', 'COUNT(*)', array( 'ar_namespace' => $this->getNamespace(),
1257                                 'ar_title' => $this->getDBkey() ), $fname );
1258                 }
1259                 return (int)$n;
1260         }
1261
1262         /**
1263          * Get the article ID for this Title from the link cache,
1264          * adding it if necessary
1265          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select
1266          *      for update
1267          * @return int the ID
1268          * @access public
1269          */
1270         function getArticleID( $flags = 0 ) {
1271                 $linkCache =& LinkCache::singleton();
1272                 if ( $flags & GAID_FOR_UPDATE ) {
1273                         $oldUpdate = $linkCache->forUpdate( true );
1274                         $this->mArticleID = $linkCache->addLinkObj( $this );
1275                         $linkCache->forUpdate( $oldUpdate );
1276                 } else {
1277                         if ( -1 == $this->mArticleID ) {
1278                                 $this->mArticleID = $linkCache->addLinkObj( $this );
1279                         }
1280                 }
1281                 return $this->mArticleID;
1282         }
1283
1284         function getLatestRevID() {
1285                 if ($this->mLatestID !== false)
1286                         return $this->mLatestID;
1287
1288                 $db =& wfGetDB(DB_SLAVE);
1289                 return $this->mLatestID = $db->selectField( 'revision',
1290                         "max(rev_id)",
1291                         array('rev_page' => $this->getArticleID()),
1292                         'Title::getLatestRevID' );
1293         }
1294
1295         /**
1296          * This clears some fields in this object, and clears any associated
1297          * keys in the "bad links" section of the link cache.
1298          *
1299          * - This is called from Article::insertNewArticle() to allow
1300          * loading of the new page_id. It's also called from
1301          * Article::doDeleteArticle()
1302          *
1303          * @param int $newid the new Article ID
1304          * @access public
1305          */
1306         function resetArticleID( $newid ) {
1307                 $linkCache =& LinkCache::singleton();
1308                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
1309
1310                 if ( 0 == $newid ) { $this->mArticleID = -1; }
1311                 else { $this->mArticleID = $newid; }
1312                 $this->mRestrictionsLoaded = false;
1313                 $this->mRestrictions = array();
1314         }
1315
1316         /**
1317          * Updates page_touched for this page; called from LinksUpdate.php
1318          * @return bool true if the update succeded
1319          * @access public
1320          */
1321         function invalidateCache() {
1322                 global $wgUseFileCache;
1323
1324                 if ( wfReadOnly() ) {
1325                         return;
1326                 }
1327
1328                 $dbw =& wfGetDB( DB_MASTER );
1329                 $success = $dbw->update( 'page',
1330                         array( /* SET */
1331                                 'page_touched' => $dbw->timestamp()
1332                         ), array( /* WHERE */
1333                                 'page_namespace' => $this->getNamespace() ,
1334                                 'page_title' => $this->getDBkey()
1335                         ), 'Title::invalidateCache'
1336                 );
1337
1338                 if ($wgUseFileCache) {
1339                         $cache = new CacheManager($this);
1340                         @unlink($cache->fileCacheName());
1341                 }
1342
1343                 return $success;
1344         }
1345
1346         /**
1347          * Prefix some arbitrary text with the namespace or interwiki prefix
1348          * of this object
1349          *
1350          * @param string $name the text
1351          * @return string the prefixed text
1352          * @access private
1353          */
1354         /* private */ function prefix( $name ) {
1355                 global $wgContLang;
1356
1357                 $p = '';
1358                 if ( '' != $this->mInterwiki ) {
1359                         $p = $this->mInterwiki . ':';
1360                 }
1361                 if ( 0 != $this->mNamespace ) {
1362                         $p .= $wgContLang->getNsText( $this->mNamespace ) . ':';
1363                 }
1364                 return $p . $name;
1365         }
1366
1367         /**
1368          * Secure and split - main initialisation function for this object
1369          *
1370          * Assumes that mDbkeyform has been set, and is urldecoded
1371          * and uses underscores, but not otherwise munged.  This function
1372          * removes illegal characters, splits off the interwiki and
1373          * namespace prefixes, sets the other forms, and canonicalizes
1374          * everything.
1375          * @return bool true on success
1376          * @access private
1377          */
1378         /* private */ function secureAndSplit() {
1379                 global $wgContLang, $wgLocalInterwiki, $wgCapitalLinks;
1380                 $fname = 'Title::secureAndSplit';
1381
1382                 # Initialisation
1383                 static $rxTc = false;
1384                 if( !$rxTc ) {
1385                         # % is needed as well
1386                         $rxTc = '/[^' . Title::legalChars() . ']|%[0-9A-Fa-f]{2}/S';
1387                 }
1388
1389                 $this->mInterwiki = $this->mFragment = '';
1390                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
1391
1392                 # Clean up whitespace
1393                 #
1394                 $t = preg_replace( '/[ _]+/', '_', $this->mDbkeyform );
1395                 $t = trim( $t, '_' );
1396
1397                 if ( '' == $t ) {
1398                         return false;
1399                 }
1400
1401                 if( false !== strpos( $t, UTF8_REPLACEMENT ) ) {
1402                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
1403                         return false;
1404                 }
1405
1406                 $this->mDbkeyform = $t;
1407
1408                 # Initial colon indicates main namespace rather than specified default
1409                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
1410                 if ( ':' == $t{0} ) {
1411                         $this->mNamespace = NS_MAIN;
1412                         $t = substr( $t, 1 ); # remove the colon but continue processing
1413                 }
1414
1415                 # Namespace or interwiki prefix
1416                 $firstPass = true;
1417                 do {
1418                         if ( preg_match( "/^(.+?)_*:_*(.*)$/S", $t, $m ) ) {
1419                                 $p = $m[1];
1420                                 $lowerNs = strtolower( $p );
1421                                 if ( $ns = Namespace::getCanonicalIndex( $lowerNs ) ) {
1422                                         # Canonical namespace
1423                                         $t = $m[2];
1424                                         $this->mNamespace = $ns;
1425                                 } elseif ( $ns = $wgContLang->getNsIndex( $lowerNs )) {
1426                                         # Ordinary namespace
1427                                         $t = $m[2];
1428                                         $this->mNamespace = $ns;
1429                                 } elseif( $this->getInterwikiLink( $p ) ) {
1430                                         if( !$firstPass ) {
1431                                                 # Can't make a local interwiki link to an interwiki link.
1432                                                 # That's just crazy!
1433                                                 return false;
1434                                         }
1435
1436                                         # Interwiki link
1437                                         $t = $m[2];
1438                                         $this->mInterwiki = strtolower( $p );
1439
1440                                         # Redundant interwiki prefix to the local wiki
1441                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
1442                                                 if( $t == '' ) {
1443                                                         # Can't have an empty self-link
1444                                                         return false;
1445                                                 }
1446                                                 $this->mInterwiki = '';
1447                                                 $firstPass = false;
1448                                                 # Do another namespace split...
1449                                                 continue;
1450                                         }
1451
1452                                         # If there's an initial colon after the interwiki, that also
1453                                         # resets the default namespace
1454                                         if ( $t !== '' && $t[0] == ':' ) {
1455                                                 $this->mNamespace = NS_MAIN;
1456                                                 $t = substr( $t, 1 );
1457                                         }
1458                                 }
1459                                 # If there's no recognized interwiki or namespace,
1460                                 # then let the colon expression be part of the title.
1461                         }
1462                         break;
1463                 } while( true );
1464                 $r = $t;
1465
1466                 # We already know that some pages won't be in the database!
1467                 #
1468                 if ( '' != $this->mInterwiki || -1 == $this->mNamespace ) {
1469                         $this->mArticleID = 0;
1470                 }
1471                 $f = strstr( $r, '#' );
1472                 if ( false !== $f ) {
1473                         $this->mFragment = substr( $f, 1 );
1474                         $r = substr( $r, 0, strlen( $r ) - strlen( $f ) );
1475                         # remove whitespace again: prevents "Foo_bar_#"
1476                         # becoming "Foo_bar_"
1477                         $r = preg_replace( '/_*$/', '', $r );
1478                 }
1479
1480                 # Reject illegal characters.
1481                 #
1482                 if( preg_match( $rxTc, $r ) ) {
1483                         return false;
1484                 }
1485
1486                 /**
1487                  * Pages with "/./" or "/../" appearing in the URLs will
1488                  * often be unreachable due to the way web browsers deal
1489                  * with 'relative' URLs. Forbid them explicitly.
1490                  */
1491                 if ( strpos( $r, '.' ) !== false &&
1492                      ( $r === '.' || $r === '..' ||
1493                        strpos( $r, './' ) === 0  ||
1494                        strpos( $r, '../' ) === 0 ||
1495                        strpos( $r, '/./' ) !== false ||
1496                        strpos( $r, '/../' ) !== false ) )
1497                 {
1498                         return false;
1499                 }
1500
1501                 # We shouldn't need to query the DB for the size.
1502                 #$maxSize = $dbr->textFieldSize( 'page', 'page_title' );
1503                 if ( strlen( $r ) > 255 ) {
1504                         return false;
1505                 }
1506
1507                 /**
1508                  * Normally, all wiki links are forced to have
1509                  * an initial capital letter so [[foo]] and [[Foo]]
1510                  * point to the same place.
1511                  *
1512                  * Don't force it for interwikis, since the other
1513                  * site might be case-sensitive.
1514                  */
1515                 if( $wgCapitalLinks && $this->mInterwiki == '') {
1516                         $t = $wgContLang->ucfirst( $r );
1517                 } else {
1518                         $t = $r;
1519                 }
1520
1521                 /**
1522                  * Can't make a link to a namespace alone...
1523                  * "empty" local links can only be self-links
1524                  * with a fragment identifier.
1525                  */
1526                 if( $t == '' &&
1527                         $this->mInterwiki == '' &&
1528                         $this->mNamespace != NS_MAIN ) {
1529                         return false;
1530                 }
1531
1532                 // Any remaining initial :s are illegal.
1533                 if ( $t !== '' && ':' == $t{0} ) {
1534                         return false;
1535                 }
1536
1537                 # Fill fields
1538                 $this->mDbkeyform = $t;
1539                 $this->mUrlform = wfUrlencode( $t );
1540
1541                 $this->mTextform = str_replace( '_', ' ', $t );
1542
1543                 return true;
1544         }
1545
1546         /**
1547          * Get a Title object associated with the talk page of this article
1548          * @return Title the object for the talk page
1549          * @access public
1550          */
1551         function getTalkPage() {
1552                 return Title::makeTitle( Namespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1553         }
1554
1555         /**
1556          * Get a title object associated with the subject page of this
1557          * talk page
1558          *
1559          * @return Title the object for the subject page
1560          * @access public
1561          */
1562         function getSubjectPage() {
1563                 return Title::makeTitle( Namespace::getSubject( $this->getNamespace() ), $this->getDBkey() );
1564         }
1565
1566         /**
1567          * Get an array of Title objects linking to this Title
1568          * Also stores the IDs in the link cache.
1569          *
1570          * @param string $options may be FOR UPDATE
1571          * @return array the Title objects linking here
1572          * @access public
1573          */
1574         function getLinksTo( $options = '', $table = 'pagelinks', $prefix = 'pl' ) {
1575                 $linkCache =& LinkCache::singleton();
1576                 $id = $this->getArticleID();
1577
1578                 if ( $options ) {
1579                         $db =& wfGetDB( DB_MASTER );
1580                 } else {
1581                         $db =& wfGetDB( DB_SLAVE );
1582                 }
1583
1584                 $res = $db->select( array( 'page', $table ),
1585                         array( 'page_namespace', 'page_title', 'page_id' ),
1586                         array(
1587                                 "{$prefix}_from=page_id",
1588                                 "{$prefix}_namespace" => $this->getNamespace(),
1589                                 "{$prefix}_title"     => $this->getDbKey() ),
1590                         'Title::getLinksTo',
1591                         $options );
1592
1593                 $retVal = array();
1594                 if ( $db->numRows( $res ) ) {
1595                         while ( $row = $db->fetchObject( $res ) ) {
1596                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
1597                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj );
1598                                         $retVal[] = $titleObj;
1599                                 }
1600                         }
1601                 }
1602                 $db->freeResult( $res );
1603                 return $retVal;
1604         }
1605
1606         /**
1607          * Get an array of Title objects using this Title as a template
1608          * Also stores the IDs in the link cache.
1609          *
1610          * @param string $options may be FOR UPDATE
1611          * @return array the Title objects linking here
1612          * @access public
1613          */
1614         function getTemplateLinksTo( $options = '' ) {
1615                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
1616         }
1617
1618         /**
1619          * Get an array of Title objects referring to non-existent articles linked from this page
1620          *
1621          * @param string $options may be FOR UPDATE
1622          * @return array the Title objects
1623          * @access public
1624          */
1625         function getBrokenLinksFrom( $options = '' ) {
1626                 if ( $options ) {
1627                         $db =& wfGetDB( DB_MASTER );
1628                 } else {
1629                         $db =& wfGetDB( DB_SLAVE );
1630                 }
1631
1632                 $res = $db->safeQuery(
1633                           "SELECT pl_namespace, pl_title
1634                              FROM !
1635                         LEFT JOIN !
1636                                ON pl_namespace=page_namespace
1637                               AND pl_title=page_title
1638                             WHERE pl_from=?
1639                               AND page_namespace IS NULL
1640                                   !",
1641                         $db->tableName( 'pagelinks' ),
1642                         $db->tableName( 'page' ),
1643                         $this->getArticleId(),
1644                         $options );
1645
1646                 $retVal = array();
1647                 if ( $db->numRows( $res ) ) {
1648                         while ( $row = $db->fetchObject( $res ) ) {
1649                                 $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
1650                         }
1651                 }
1652                 $db->freeResult( $res );
1653                 return $retVal;
1654         }
1655
1656
1657         /**
1658          * Get a list of URLs to purge from the Squid cache when this
1659          * page changes
1660          *
1661          * @return array the URLs
1662          * @access public
1663          */
1664         function getSquidURLs() {
1665                 return array(
1666                         $this->getInternalURL(),
1667                         $this->getInternalURL( 'action=history' )
1668                 );
1669         }
1670
1671         /**
1672          * Move this page without authentication
1673          * @param Title &$nt the new page Title
1674          * @access public
1675          */
1676         function moveNoAuth( &$nt ) {
1677                 return $this->moveTo( $nt, false );
1678         }
1679
1680         /**
1681          * Check whether a given move operation would be valid.
1682          * Returns true if ok, or a message key string for an error message
1683          * if invalid. (Scarrrrry ugly interface this.)
1684          * @param Title &$nt the new title
1685          * @param bool $auth indicates whether $wgUser's permissions
1686          *      should be checked
1687          * @return mixed true on success, message name on failure
1688          * @access public
1689          */
1690         function isValidMoveOperation( &$nt, $auth = true ) {
1691                 if( !$this or !$nt ) {
1692                         return 'badtitletext';
1693                 }
1694                 if( $this->equals( $nt ) ) {
1695                         return 'selfmove';
1696                 }
1697                 if( !$this->isMovable() || !$nt->isMovable() ) {
1698                         return 'immobile_namespace';
1699                 }
1700
1701                 $oldid = $this->getArticleID();
1702                 $newid = $nt->getArticleID();
1703
1704                 if ( strlen( $nt->getDBkey() ) < 1 ) {
1705                         return 'articleexists';
1706                 }
1707                 if ( ( '' == $this->getDBkey() ) ||
1708                          ( !$oldid ) ||
1709                      ( '' == $nt->getDBkey() ) ) {
1710                         return 'badarticleerror';
1711                 }
1712
1713                 if ( $auth && (
1714                                 !$this->userCanEdit() || !$nt->userCanEdit() ||
1715                                 !$this->userCanMove() || !$nt->userCanMove() ) ) {
1716                         return 'protectedpage';
1717                 }
1718
1719                 # The move is allowed only if (1) the target doesn't exist, or
1720                 # (2) the target is a redirect to the source, and has no history
1721                 # (so we can undo bad moves right after they're done).
1722
1723                 if ( 0 != $newid ) { # Target exists; check for validity
1724                         if ( ! $this->isValidMoveTarget( $nt ) ) {
1725                                 return 'articleexists';
1726                         }
1727                 }
1728                 return true;
1729         }
1730
1731         /**
1732          * Move a title to a new location
1733          * @param Title &$nt the new title
1734          * @param bool $auth indicates whether $wgUser's permissions
1735          *      should be checked
1736          * @return mixed true on success, message name on failure
1737          * @access public
1738          */
1739         function moveTo( &$nt, $auth = true, $reason = '' ) {
1740                 $err = $this->isValidMoveOperation( $nt, $auth );
1741                 if( is_string( $err ) ) {
1742                         return $err;
1743                 }
1744
1745                 $pageid = $this->getArticleID();
1746                 if( $nt->exists() ) {
1747                         $this->moveOverExistingRedirect( $nt, $reason );
1748                         $pageCountChange = 0;
1749                 } else { # Target didn't exist, do normal move.
1750                         $this->moveToNewTitle( $nt, $reason );
1751                         $pageCountChange = 1;
1752                 }
1753                 $redirid = $this->getArticleID();
1754
1755                 # Fixing category links (those without piped 'alternate' names) to be sorted under the new title
1756                 $dbw =& wfGetDB( DB_MASTER );
1757                 $categorylinks = $dbw->tableName( 'categorylinks' );
1758                 $sql = "UPDATE $categorylinks SET cl_sortkey=" . $dbw->addQuotes( $nt->getPrefixedText() ) .
1759                         " WHERE cl_from=" . $dbw->addQuotes( $pageid ) .
1760                         " AND cl_sortkey=" . $dbw->addQuotes( $this->getPrefixedText() );
1761                 $dbw->query( $sql, 'SpecialMovepage::doSubmit' );
1762
1763                 # Update watchlists
1764
1765                 $oldnamespace = $this->getNamespace() & ~1;
1766                 $newnamespace = $nt->getNamespace() & ~1;
1767                 $oldtitle = $this->getDBkey();
1768                 $newtitle = $nt->getDBkey();
1769
1770                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
1771                         WatchedItem::duplicateEntries( $this, $nt );
1772                 }
1773
1774                 # Update search engine
1775                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
1776                 $u->doUpdate();
1777                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
1778                 $u->doUpdate();
1779
1780                 # Update site_stats
1781                 if ( $this->getNamespace() == NS_MAIN and $nt->getNamespace() != NS_MAIN ) {
1782                         # Moved out of main namespace
1783                         # not viewed, edited, removing
1784                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange);
1785                 } elseif ( $this->getNamespace() != NS_MAIN and $nt->getNamespace() == NS_MAIN ) {
1786                         # Moved into main namespace
1787                         # not viewed, edited, adding
1788                         $u = new SiteStatsUpdate( 0, 1, +1, $pageCountChange );
1789                 } elseif ( $pageCountChange ) {
1790                         # Added redirect
1791                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
1792                 } else{
1793                         $u = false;
1794                 }
1795                 if ( $u ) {
1796                         $u->doUpdate();
1797                 }
1798
1799                 global $wgUser;
1800                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
1801                 return true;
1802         }
1803
1804         /**
1805          * Move page to a title which is at present a redirect to the
1806          * source page
1807          *
1808          * @param Title &$nt the page to move to, which should currently
1809          *      be a redirect
1810          * @access private
1811          */
1812         function moveOverExistingRedirect( &$nt, $reason = '' ) {
1813                 global $wgUseSquid, $wgMwRedir;
1814                 $fname = 'Title::moveOverExistingRedirect';
1815                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
1816
1817                 if ( $reason ) {
1818                         $comment .= ": $reason";
1819                 }
1820
1821                 $now = wfTimestampNow();
1822                 $rand = wfRandom();
1823                 $newid = $nt->getArticleID();
1824                 $oldid = $this->getArticleID();
1825                 $dbw =& wfGetDB( DB_MASTER );
1826                 $linkCache =& LinkCache::singleton();
1827
1828                 # Delete the old redirect. We don't save it to history since
1829                 # by definition if we've got here it's rather uninteresting.
1830                 # We have to remove it so that the next step doesn't trigger
1831                 # a conflict on the unique namespace+title index...
1832                 $dbw->delete( 'page', array( 'page_id' => $newid ), $fname );
1833
1834                 # Save a null revision in the page's history notifying of the move
1835                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
1836                 $nullRevId = $nullRevision->insertOn( $dbw );
1837
1838                 # Change the name of the target page:
1839                 $dbw->update( 'page',
1840                         /* SET */ array(
1841                                 'page_touched'   => $dbw->timestamp($now),
1842                                 'page_namespace' => $nt->getNamespace(),
1843                                 'page_title'     => $nt->getDBkey(),
1844                                 'page_latest'    => $nullRevId,
1845                         ),
1846                         /* WHERE */ array( 'page_id' => $oldid ),
1847                         $fname
1848                 );
1849                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
1850
1851                 # Recreate the redirect, this time in the other direction.
1852                 $redirectText = $wgMwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
1853                 $redirectArticle = new Article( $this );
1854                 $newid = $redirectArticle->insertOn( $dbw );
1855                 $redirectRevision = new Revision( array(
1856                         'page'    => $newid,
1857                         'comment' => $comment,
1858                         'text'    => $redirectText ) );
1859                 $revid = $redirectRevision->insertOn( $dbw );
1860                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
1861                 $linkCache->clearLink( $this->getPrefixedDBkey() );
1862
1863                 # Log the move
1864                 $log = new LogPage( 'move' );
1865                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText() ) );
1866
1867                 # Now, we record the link from the redirect to the new title.
1868                 # It should have no other outgoing links...
1869                 $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), $fname );
1870                 $dbw->insert( 'pagelinks',
1871                         array(
1872                                 'pl_from'      => $newid,
1873                                 'pl_namespace' => $nt->getNamespace(),
1874                                 'pl_title'     => $nt->getDbKey() ),
1875                         $fname );
1876
1877                 # Purge squid
1878                 if ( $wgUseSquid ) {
1879                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
1880                         $u = new SquidUpdate( $urls );
1881                         $u->doUpdate();
1882                 }
1883         }
1884
1885         /**
1886          * Move page to non-existing title.
1887          * @param Title &$nt the new Title
1888          * @access private
1889          */
1890         function moveToNewTitle( &$nt, $reason = '' ) {
1891                 global $wgUseSquid;
1892                 global $wgMwRedir;
1893                 $fname = 'MovePageForm::moveToNewTitle';
1894                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
1895                 if ( $reason ) {
1896                         $comment .= ": $reason";
1897                 }
1898
1899                 $newid = $nt->getArticleID();
1900                 $oldid = $this->getArticleID();
1901                 $dbw =& wfGetDB( DB_MASTER );
1902                 $now = $dbw->timestamp();
1903                 $rand = wfRandom();
1904                 $linkCache =& LinkCache::singleton();
1905
1906                 # Save a null revision in the page's history notifying of the move
1907                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
1908                 $nullRevId = $nullRevision->insertOn( $dbw );
1909
1910                 # Rename cur entry
1911                 $dbw->update( 'page',
1912                         /* SET */ array(
1913                                 'page_touched'   => $now,
1914                                 'page_namespace' => $nt->getNamespace(),
1915                                 'page_title'     => $nt->getDBkey(),
1916                                 'page_latest'    => $nullRevId,
1917                         ),
1918                         /* WHERE */ array( 'page_id' => $oldid ),
1919                         $fname
1920                 );
1921
1922                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
1923
1924                 # Insert redirect
1925                 $redirectText = $wgMwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
1926                 $redirectArticle = new Article( $this );
1927                 $newid = $redirectArticle->insertOn( $dbw );
1928                 $redirectRevision = new Revision( array(
1929                         'page'    => $newid,
1930                         'comment' => $comment,
1931                         'text'    => $redirectText ) );
1932                 $revid = $redirectRevision->insertOn( $dbw );
1933                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
1934                 $linkCache->clearLink( $this->getPrefixedDBkey() );
1935
1936                 # Log the move
1937                 $log = new LogPage( 'move' );
1938                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText()) );
1939
1940                 # Purge caches as per article creation
1941                 Article::onArticleCreate( $nt );
1942
1943                 # Record the just-created redirect's linking to the page
1944                 $dbw->insert( 'pagelinks',
1945                         array(
1946                                 'pl_from'      => $newid,
1947                                 'pl_namespace' => $nt->getNamespace(),
1948                                 'pl_title'     => $nt->getDBkey() ),
1949                         $fname );
1950
1951                 # Non-existent target may have had broken links to it; these must
1952                 # now be touched to update link coloring.
1953                 $nt->touchLinks();
1954
1955                 # Purge old title from squid
1956                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
1957                 $titles = $nt->getLinksTo();
1958                 if ( $wgUseSquid ) {
1959                         $urls = $this->getSquidURLs();
1960                         foreach ( $titles as $linkTitle ) {
1961                                 $urls[] = $linkTitle->getInternalURL();
1962                         }
1963                         $u = new SquidUpdate( $urls );
1964                         $u->doUpdate();
1965                 }
1966         }
1967
1968         /**
1969          * Checks if $this can be moved to a given Title
1970          * - Selects for update, so don't call it unless you mean business
1971          *
1972          * @param Title &$nt the new title to check
1973          * @access public
1974          */
1975         function isValidMoveTarget( $nt ) {
1976
1977                 $fname = 'Title::isValidMoveTarget';
1978                 $dbw =& wfGetDB( DB_MASTER );
1979
1980                 # Is it a redirect?
1981                 $id  = $nt->getArticleID();
1982                 $obj = $dbw->selectRow( array( 'page', 'revision', 'text'),
1983                         array( 'page_is_redirect','old_text','old_flags' ),
1984                         array( 'page_id' => $id, 'page_latest=rev_id', 'rev_text_id=old_id' ),
1985                         $fname, 'FOR UPDATE' );
1986
1987                 if ( !$obj || 0 == $obj->page_is_redirect ) {
1988                         # Not a redirect
1989                         return false;
1990                 }
1991                 $text = Revision::getRevisionText( $obj );
1992
1993                 # Does the redirect point to the source?
1994                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
1995                         $redirTitle = Title::newFromText( $m[1] );
1996                         if( !is_object( $redirTitle ) ||
1997                                 $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() ) {
1998                                 return false;
1999                         }
2000                 } else {
2001                         # Fail safe
2002                         return false;
2003                 }
2004
2005                 # Does the article have a history?
2006                 $row = $dbw->selectRow( array( 'page', 'revision'),
2007                         array( 'rev_id' ),
2008                         array( 'page_namespace' => $nt->getNamespace(),
2009                                 'page_title' => $nt->getDBkey(),
2010                                 'page_id=rev_page AND page_latest != rev_id'
2011                         ), $fname, 'FOR UPDATE'
2012                 );
2013
2014                 # Return true if there was no history
2015                 return $row === false;
2016         }
2017
2018         /**
2019          * Create a redirect; fails if the title already exists; does
2020          * not notify RC
2021          *
2022          * @param Title $dest the destination of the redirect
2023          * @param string $comment the comment string describing the move
2024          * @return bool true on success
2025          * @access public
2026          */
2027         function createRedirect( $dest, $comment ) {
2028                 if ( $this->getArticleID() ) {
2029                         return false;
2030                 }
2031
2032                 $fname = 'Title::createRedirect';
2033                 $dbw =& wfGetDB( DB_MASTER );
2034
2035                 $article = new Article( $this );
2036                 $newid = $article->insertOn( $dbw );
2037                 $revision = new Revision( array(
2038                         'page'      => $newid,
2039                         'comment'   => $comment,
2040                         'text'      => "#REDIRECT [[" . $dest->getPrefixedText() . "]]\n",
2041                         ) );
2042                 $revisionId = $revision->insertOn( $dbw );
2043                 $article->updateRevisionOn( $dbw, $revision, 0 );
2044
2045                 # Link table
2046                 $dbw->insert( 'pagelinks',
2047                         array(
2048                                 'pl_from'      => $newid,
2049                                 'pl_namespace' => $dest->getNamespace(),
2050                                 'pl_title'     => $dest->getDbKey()
2051                         ), $fname
2052                 );
2053
2054                 Article::onArticleCreate( $this );
2055                 return true;
2056         }
2057
2058         /**
2059          * Get categories to which this Title belongs and return an array of
2060          * categories' names.
2061          *
2062          * @return array an array of parents in the form:
2063          *      $parent => $currentarticle
2064          * @access public
2065          */
2066         function getParentCategories() {
2067                 global $wgContLang;
2068
2069                 $titlekey = $this->getArticleId();
2070                 $dbr =& wfGetDB( DB_SLAVE );
2071                 $categorylinks = $dbr->tableName( 'categorylinks' );
2072
2073                 # NEW SQL
2074                 $sql = "SELECT * FROM $categorylinks"
2075                      ." WHERE cl_from='$titlekey'"
2076                          ." AND cl_from <> '0'"
2077                          ." ORDER BY cl_sortkey";
2078
2079                 $res = $dbr->query ( $sql ) ;
2080
2081                 if($dbr->numRows($res) > 0) {
2082                         while ( $x = $dbr->fetchObject ( $res ) )
2083                                 //$data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to);
2084                                 $data[$wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to] = $this->getFullText();
2085                         $dbr->freeResult ( $res ) ;
2086                 } else {
2087                         $data = '';
2088                 }
2089                 return $data;
2090         }
2091
2092         /**
2093          * Get a tree of parent categories
2094          * @param array $children an array with the children in the keys, to check for circular refs
2095          * @return array
2096          * @access public
2097          */
2098         function getParentCategoryTree( $children = array() ) {
2099                 $parents = $this->getParentCategories();
2100
2101                 if($parents != '') {
2102                         foreach($parents as $parent => $current) {
2103                                 if ( array_key_exists( $parent, $children ) ) {
2104                                         # Circular reference
2105                                         $stack[$parent] = array();
2106                                 } else {
2107                                         $nt = Title::newFromText($parent);
2108                                         $stack[$parent] = $nt->getParentCategoryTree( $children + array($parent => 1) );
2109                                 }
2110                         }
2111                         return $stack;
2112                 } else {
2113                         return array();
2114                 }
2115         }
2116
2117
2118         /**
2119          * Get an associative array for selecting this title from
2120          * the "page" table
2121          *
2122          * @return array
2123          * @access public
2124          */
2125         function pageCond() {
2126                 return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
2127         }
2128
2129         /**
2130          * Get the revision ID of the previous revision
2131          *
2132          * @param integer $revision  Revision ID. Get the revision that was before this one.
2133          * @return interger $oldrevision|false
2134          */
2135         function getPreviousRevisionID( $revision ) {
2136                 $dbr =& wfGetDB( DB_SLAVE );
2137                 return $dbr->selectField( 'revision', 'rev_id',
2138                         'rev_page=' . intval( $this->getArticleId() ) .
2139                         ' AND rev_id<' . intval( $revision ) . ' ORDER BY rev_id DESC' );
2140         }
2141
2142         /**
2143          * Get the revision ID of the next revision
2144          *
2145          * @param integer $revision  Revision ID. Get the revision that was after this one.
2146          * @return interger $oldrevision|false
2147          */
2148         function getNextRevisionID( $revision ) {
2149                 $dbr =& wfGetDB( DB_SLAVE );
2150                 return $dbr->selectField( 'revision', 'rev_id',
2151                         'rev_page=' . intval( $this->getArticleId() ) .
2152                         ' AND rev_id>' . intval( $revision ) . ' ORDER BY rev_id' );
2153         }
2154
2155         /**
2156          * Compare with another title.
2157          *
2158          * @param Title $title
2159          * @return bool
2160          */
2161         function equals( $title ) {
2162                 // Note: === is necessary for proper matching of number-like titles.
2163                 return $this->getInterwiki() === $title->getInterwiki()
2164                         && $this->getNamespace() == $title->getNamespace()
2165                         && $this->getDbkey() === $title->getDbkey();
2166         }
2167
2168         /**
2169          * Check if page exists
2170          * @return bool
2171          */
2172         function exists() {
2173                 return $this->getArticleId() != 0;
2174         }
2175
2176         /**
2177          * Should a link should be displayed as a known link, just based on its title?
2178          *
2179          * Currently, a self-link with a fragment and special pages are in
2180          * this category. Special pages never exist in the database.
2181          */
2182         function isAlwaysKnown() {
2183                 return  $this->isExternal() || ( 0 == $this->mNamespace && "" == $this->mDbkeyform )
2184                   || NS_SPECIAL == $this->mNamespace;
2185         }
2186
2187         /**
2188          * Update page_touched timestamps on pages linking to this title.
2189          * In principal, this could be backgrounded and could also do squid
2190          * purging.
2191          */
2192         function touchLinks() {
2193                 $fname = 'Title::touchLinks';
2194
2195                 $dbw =& wfGetDB( DB_MASTER );
2196
2197                 $res = $dbw->select( 'pagelinks',
2198                         array( 'pl_from' ),
2199                         array(
2200                                 'pl_namespace' => $this->getNamespace(),
2201                                 'pl_title'     => $this->getDbKey() ),
2202                         $fname );
2203
2204                 $toucharr = array();
2205                 while( $row = $dbw->fetchObject( $res ) ) {
2206                         $toucharr[] = $row->pl_from;
2207                 }
2208                 $dbw->freeResult( $res );
2209
2210                 if( $this->getNamespace() == NS_CATEGORY ) {
2211                         // Categories show up in a separate set of links as well
2212                         $res = $dbw->select( 'categorylinks',
2213                                 array( 'cl_from' ),
2214                                 array( 'cl_to' => $this->getDbKey() ),
2215                                 $fname );
2216                         while( $row = $dbw->fetchObject( $res ) ) {
2217                                 $toucharr[] = $row->cl_from;
2218                         }
2219                         $dbw->freeResult( $res );
2220                 }
2221
2222                 if (!count($toucharr))
2223                         return;
2224                 $dbw->update( 'page', /* SET */ array( 'page_touched' => $dbw->timestamp() ),
2225                                                         /* WHERE */ array( 'page_id' => $toucharr ),$fname);
2226         }
2227
2228         function trackbackURL() {
2229                 global $wgTitle, $wgScriptPath, $wgServer;
2230
2231                 return "$wgServer$wgScriptPath/trackback.php?article="
2232                         . htmlspecialchars(urlencode($wgTitle->getPrefixedDBkey()));
2233         }
2234
2235         function trackbackRDF() {
2236                 $url = htmlspecialchars($this->getFullURL());
2237                 $title = htmlspecialchars($this->getText());
2238                 $tburl = $this->trackbackURL();
2239
2240                 return "
2241 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
2242          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
2243          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
2244 <rdf:Description
2245    rdf:about=\"$url\"
2246    dc:identifier=\"$url\"
2247    dc:title=\"$title\"
2248    trackback:ping=\"$tburl\" />
2249 </rdf:RDF>";
2250         }
2251
2252         /**
2253          * Generate strings used for xml 'id' names in monobook tabs
2254          * @return string
2255          */
2256         function getNamespaceKey() {
2257                 switch ($this->getNamespace()) {
2258                         case NS_MAIN:
2259                         case NS_TALK:
2260                                 return 'nstab-main';
2261                         case NS_USER:
2262                         case NS_USER_TALK:
2263                                 return 'nstab-user';
2264                         case NS_MEDIA:
2265                                 return 'nstab-media';
2266                         case NS_SPECIAL:
2267                                 return 'nstab-special';
2268                         case NS_PROJECT:
2269                         case NS_PROJECT_TALK:
2270                                 return 'nstab-project';
2271                         case NS_IMAGE:
2272                         case NS_IMAGE_TALK:
2273                                 return 'nstab-image';
2274                         case NS_MEDIAWIKI:
2275                         case NS_MEDIAWIKI_TALK:
2276                                 return 'nstab-mediawiki';
2277                         case NS_TEMPLATE:
2278                         case NS_TEMPLATE_TALK:
2279                                 return 'nstab-template';
2280                         case NS_HELP:
2281                         case NS_HELP_TALK:
2282                                 return 'nstab-help';
2283                         case NS_CATEGORY:
2284                         case NS_CATEGORY_TALK:
2285                                 return 'nstab-category';
2286                         default:
2287                                 return 'nstab-' . strtolower( $this->getSubjectNsText() );
2288                 }
2289         }
2290 }
2291 ?>