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 interwiki prefix (or null string)
 609          * @return string
 610          * @access public
 611          */
 612         function getInterwiki() { return $this->mInterwiki; }
 613         /**
 614          * Get the Title fragment (i.e. the bit after the #)
 615          * @return string
 616          * @access public
 617          */
 618         function getFragment() { return $this->mFragment; }
 619         /**
 620          * Get the default namespace index, for when there is no namespace
 621          * @return int
 622          * @access public
 623          */
 624         function getDefaultNamespace() { return $this->mDefaultNamespace; }
 625
 626         /**
 627          * Get title for search index
 628          * @return string a stripped-down title string ready for the
 629          *      search index
 630          */
 631         function getIndexTitle() {
 632                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 633         }
 634
 635         /**
 636          * Get the prefixed database key form
 637          * @return string the prefixed title, with underscores and
 638          *      any interwiki and namespace prefixes
 639          * @access public
 640          */
 641         function getPrefixedDBkey() {
 642                 $s = $this->prefix( $this->mDbkeyform );
 643                 $s = str_replace( ' ', '_', $s );
 644                 return $s;
 645         }
 646
 647         /**
 648          * Get the prefixed title with spaces.
 649          * This is the form usually used for display
 650          * @return string the prefixed title, with spaces
 651          * @access public
 652          */
 653         function getPrefixedText() {
 654                 global $wgContLang;
 655                 if ( empty( $this->mPrefixedText ) ) { // FIXME: bad usage of empty() ?
 656                         $s = $this->prefix( $this->mTextform );
 657                         $s = str_replace( '_', ' ', $s );
 658                         $this->mPrefixedText = $s;
 659                 }
 660                 return $this->mPrefixedText;
 661         }
 662
 663         /**
 664          * Get the prefixed title with spaces, plus any fragment
 665          * (part beginning with '#')
 666          * @return string the prefixed title, with spaces and
 667          *      the fragment, including '#'
 668          * @access public
 669          */
 670         function getFullText() {
 671                 global $wgContLang;
 672                 $text = $this->getPrefixedText();
 673                 if( '' != $this->mFragment ) {
 674                         $text .= '#' . $this->mFragment;
 675                 }
 676                 return $text;
 677         }
 678
 679         /**
 680          * Get a URL-encoded title (not an actual URL) including interwiki
 681          * @return string the URL-encoded form
 682          * @access public
 683          */
 684         function getPrefixedURL() {
 685                 $s = $this->prefix( $this->mDbkeyform );
 686                 $s = str_replace( ' ', '_', $s );
 687
 688                 $s = wfUrlencode ( $s ) ;
 689
 690                 # Cleaning up URL to make it look nice -- is this safe?
 691                 $s = str_replace( '%28', '(', $s );
 692                 $s = str_replace( '%29', ')', $s );
 693
 694                 return $s;
 695         }
 696
 697         /**
 698          * Get a real URL referring to this title, with interwiki link and
 699          * fragment
 700          *
 701          * @param string $query an optional query string, not used
 702          *      for interwiki links
 703          * @return string the URL
 704          * @access public
 705          */
 706         function getFullURL( $query = '' ) {
 707                 global $wgContLang, $wgServer, $wgRequest;
 708
 709                 if ( '' == $this->mInterwiki ) {
 710                         $url = $this->getLocalUrl( $query );
 711
 712                         // Ugly quick hack to avoid duplicate prefixes (bug 4571 etc)
 713                         // Correct fix would be to move the prepending elsewhere.
 714                         if ($wgRequest->getVal('action') != 'render') {
 715                                 $url = $wgServer . $url;
 716                         }
 717                 } else {
 718                         $baseUrl = $this->getInterwikiLink( $this->mInterwiki );
 719
 720                         $namespace = $wgContLang->getNsText( $this->mNamespace );
 721                         if ( '' != $namespace ) {
 722                                 # Can this actually happen? Interwikis shouldn't be parsed.
 723                                 $namespace .= ':';
 724                         }
 725                         $url = str_replace( '$1', $namespace . $this->mUrlform, $baseUrl );
 726                         if( $query != '' ) {
 727                                 if( false === strpos( $url, '?' ) ) {
 728                                         $url .= '?';
 729                                 } else {
 730                                         $url .= '&';
 731                                 }
 732                                 $url .= $query;
 733                         }
 734                         if ( '' != $this->mFragment ) {
 735                                 $url .= '#' . $this->mFragment;
 736                         }
 737                 }
 738                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
 739                 return $url;
 740         }
 741
 742         /**
 743          * Get a URL with no fragment or server name.  If this page is generated
 744          * with action=render, $wgServer is prepended.
 745          * @param string $query an optional query string; if not specified,
 746          *      $wgArticlePath will be used.
 747          * @return string the URL
 748          * @access public
 749          */
 750         function getLocalURL( $query = '' ) {
 751                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
 752
 753                 if ( $this->isExternal() ) {
 754                         $url = $this->getFullURL();
 755                         if ( $query ) {
 756                                 // This is currently only used for edit section links in the
 757                                 // context of interwiki transclusion. In theory we should
 758                                 // append the query to the end of any existing query string,
 759                                 // but interwiki transclusion is already broken in that case.
 760                                 $url .= "?$query";
 761                         }
 762                 } else {
 763                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 764                         if ( $query == '' ) {
 765                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
 766                         } else {
 767                                 global $wgActionPaths;
 768                                 $url = false;
 769                                 if( !empty( $wgActionPaths ) &&
 770                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
 771                                 {
 772                                         $action = urldecode( $matches[2] );
 773                                         if( isset( $wgActionPaths[$action] ) ) {
 774                                                 $query = $matches[1];
 775                                                 if( isset( $matches[4] ) ) $query .= $matches[4];
 776                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
 777                                                 if( $query != '' ) $url .= '?' . $query;
 778                                         }
 779                                 }
 780                                 if ( $url === false ) {
 781                                         if ( $query == '-' ) {
 782                                                 $query = '';
 783                                         }
 784                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
 785                                 }
 786                         }
 787
 788                         // FIXME: this causes breakage in various places when we
 789                         // actually expected a local URL and end up with dupe prefixes.
 790                         if ($wgRequest->getVal('action') == 'render') {
 791                                 $url = $wgServer . $url;
 792                         }
 793                 }
 794                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
 795                 return $url;
 796         }
 797
 798         /**
 799          * Get an HTML-escaped version of the URL form, suitable for
 800          * using in a link, without a server name or fragment
 801          * @param string $query an optional query string
 802          * @return string the URL
 803          * @access public
 804          */
 805         function escapeLocalURL( $query = '' ) {
 806                 return htmlspecialchars( $this->getLocalURL( $query ) );
 807         }
 808
 809         /**
 810          * Get an HTML-escaped version of the URL form, suitable for
 811          * using in a link, including the server name and fragment
 812          *
 813          * @return string the URL
 814          * @param string $query an optional query string
 815          * @access public
 816          */
 817         function escapeFullURL( $query = '' ) {
 818                 return htmlspecialchars( $this->getFullURL( $query ) );
 819         }
 820
 821         /**
 822          * Get the URL form for an internal link.
 823          * - Used in various Squid-related code, in case we have a different
 824          * internal hostname for the server from the exposed one.
 825          *
 826          * @param string $query an optional query string
 827          * @return string the URL
 828          * @access public
 829          */
 830         function getInternalURL( $query = '' ) {
 831                 global $wgInternalServer;
 832                 $url = $wgInternalServer . $this->getLocalURL( $query );
 833                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
 834                 return $url;
 835         }
 836
 837         /**
 838          * Get the edit URL for this Title
 839          * @return string the URL, or a null string if this is an
 840          *      interwiki link
 841          * @access public
 842          */
 843         function getEditURL() {
 844                 global $wgServer, $wgScript;
 845
 846                 if ( '' != $this->mInterwiki ) { return ''; }
 847                 $s = $this->getLocalURL( 'action=edit' );
 848
 849                 return $s;
 850         }
 851
 852         /**
 853          * Get the HTML-escaped displayable text form.
 854          * Used for the title field in <a> tags.
 855          * @return string the text, including any prefixes
 856          * @access public
 857          */
 858         function getEscapedText() {
 859                 return htmlspecialchars( $this->getPrefixedText() );
 860         }
 861
 862         /**
 863          * Is this Title interwiki?
 864          * @return boolean
 865          * @access public
 866          */
 867         function isExternal() { return ( '' != $this->mInterwiki ); }
 868
 869         /**
 870          * Is this page "semi-protected" - the *only* protection is autoconfirm?
 871          *
 872          * @param string Action to check (default: edit)
 873          * @return bool
 874          */
 875         function isSemiProtected( $action = 'edit' ) {
 876                 $restrictions = $this->getRestrictions( $action );
 877                 # We do a full compare because this could be an array
 878                 foreach( $restrictions as $restriction ) {
 879                         if( strtolower( $restriction ) != 'autoconfirmed' ) {
 880                                 return( false );
 881                         }
 882                 }
 883                 return( true );
 884         }
 885
 886         /**
 887          * Does the title correspond to a protected article?
 888          * @param string $what the action the page is protected from,
 889          *      by default checks move and edit
 890          * @return boolean
 891          * @access public
 892          */
 893         function isProtected( $action = '' ) {
 894                 global $wgRestrictionLevels;
 895                 if ( -1 == $this->mNamespace ) { return true; }
 896
 897                 if( $action == 'edit' || $action == '' ) {
 898                         $r = $this->getRestrictions( 'edit' );
 899                         foreach( $wgRestrictionLevels as $level ) {
 900                                 if( in_array( $level, $r ) && $level != '' ) {
 901                                         return( true );
 902                                 }
 903                         }
 904                 }
 905
 906                 if( $action == 'move' || $action == '' ) {
 907                         $r = $this->getRestrictions( 'move' );
 908                         foreach( $wgRestrictionLevels as $level ) {
 909                                 if( in_array( $level, $r ) && $level != '' ) {
 910                                         return( true );
 911                                 }
 912                         }
 913                 }
 914
 915                 return false;
 916         }
 917
 918         /**
 919          * Is $wgUser is watching this page?
 920          * @return boolean
 921          * @access public
 922          */
 923         function userIsWatching() {
 924                 global $wgUser;
 925
 926                 if ( is_null( $this->mWatched ) ) {
 927                         if ( -1 == $this->mNamespace || 0 == $wgUser->getID()) {
 928                                 $this->mWatched = false;
 929                         } else {
 930                                 $this->mWatched = $wgUser->isWatched( $this );
 931                         }
 932                 }
 933                 return $this->mWatched;
 934         }
 935
 936         /**
 937          * Can $wgUser perform $action this page?
 938          * @param string $action action that permission needs to be checked for
 939          * @return boolean
 940          * @access private
 941          */
 942         function userCan($action) {
 943                 $fname = 'Title::userCan';
 944                 wfProfileIn( $fname );
 945
 946                 global $wgUser;
 947
 948                 $result = true;
 949                 if ( !wfRunHooks( 'userCan', array( &$this, &$wgUser, $action, &$result ) ) ) {
 950                         wfProfileOut( $fname );
 951                         return $result;
 952                 }
 953
 954                 if( NS_SPECIAL == $this->mNamespace ) {
 955                         wfProfileOut( $fname );
 956                         return false;
 957                 }
 958                 // XXX: This is the code that prevents unprotecting a page in NS_MEDIAWIKI
 959                 // from taking effect -ævar
 960                 if( NS_MEDIAWIKI == $this->mNamespace &&
 961                     !$wgUser->isAllowed('editinterface') ) {
 962                         wfProfileOut( $fname );
 963                         return false;
 964                 }
 965
 966                 if( $this->mDbkeyform == '_' ) {
 967                         # FIXME: Is this necessary? Shouldn't be allowed anyway...
 968                         wfProfileOut( $fname );
 969                         return false;
 970                 }
 971
 972                 # protect global styles and js
 973                 if ( NS_MEDIAWIKI == $this->mNamespace
 974                  && preg_match("/\\.(css|js)$/", $this->mTextform )
 975                      && !$wgUser->isAllowed('editinterface') ) {
 976                         wfProfileOut( $fname );
 977                         return false;
 978                 }
 979
 980                 # protect css/js subpages of user pages
 981                 # XXX: this might be better using restrictions
 982                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssJsSubpage() from working
 983                 if( NS_USER == $this->mNamespace
 984                         && preg_match("/\\.(css|js)$/", $this->mTextform )
 985                         && !$wgUser->isAllowed('editinterface')
 986                         && !preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) ) {
 987                         wfProfileOut( $fname );
 988                         return false;
 989                 }
 990
 991                 foreach( $this->getRestrictions($action) as $right ) {
 992                         // Backwards compatibility, rewrite sysop -> protect
 993                         if ( $right == 'sysop' ) {
 994                                 $right = 'protect';
 995                         }
 996                         if( '' != $right && !$wgUser->isAllowed( $right ) ) {
 997                                 wfProfileOut( $fname );
 998                                 return false;
 999                         }
1000                 }
1001
1002                 if( $action == 'move' &&
1003                         !( $this->isMovable() && $wgUser->isAllowed( 'move' ) ) ) {
1004                         wfProfileOut( $fname );
1005                         return false;
1006                 }
1007
1008                 if( $action == 'create' ) {
1009                         if( (  $this->isTalkPage() && !$wgUser->isAllowed( 'createtalk' ) ) ||
1010                                 ( !$this->isTalkPage() && !$wgUser->isAllowed( 'createpage' ) ) ) {
1011                                 return false;
1012                         }
1013                 }
1014
1015                 wfProfileOut( $fname );
1016                 return true;
1017         }
1018
1019         /**
1020          * Can $wgUser edit this page?
1021          * @return boolean
1022          * @access public
1023          */
1024         function userCanEdit() {
1025                 return $this->userCan('edit');
1026         }
1027
1028         /**
1029          * Can $wgUser move this page?
1030          * @return boolean
1031          * @access public
1032          */
1033         function userCanMove() {
1034                 return $this->userCan('move');
1035         }
1036
1037         /**
1038          * Would anybody with sufficient privileges be able to move this page?
1039          * Some pages just aren't movable.
1040          *
1041          * @return boolean
1042          * @access public
1043          */
1044         function isMovable() {
1045                 return Namespace::isMovable( $this->getNamespace() )
1046                         && $this->getInterwiki() == '';
1047         }
1048
1049         /**
1050          * Can $wgUser read this page?
1051          * @return boolean
1052          * @access public
1053          */
1054         function userCanRead() {
1055                 global $wgUser;
1056
1057                 $result = true;
1058                         if ( !wfRunHooks( 'userCan', array( &$this, &$wgUser, "read", &$result ) ) ) {
1059                         return $result;
1060                 }
1061
1062                 if( $wgUser->isAllowed('read') ) {
1063                         return true;
1064                 } else {
1065                         global $wgWhitelistRead;
1066
1067                         /** If anon users can create an account,
1068                             they need to reach the login page first! */
1069                         if( $wgUser->isAllowed( 'createaccount' )
1070                             && $this->getNamespace() == NS_SPECIAL
1071                             && $this->getText() == 'Userlogin' ) {
1072                                 return true;
1073                         }
1074
1075                         /** some pages are explicitly allowed */
1076                         $name = $this->getPrefixedText();
1077                         if( $wgWhitelistRead && in_array( $name, $wgWhitelistRead ) ) {
1078                                 return true;
1079                         }
1080
1081                         # Compatibility with old settings
1082                         if( $wgWhitelistRead && $this->getNamespace() == NS_MAIN ) {
1083                                 if( in_array( ':' . $name, $wgWhitelistRead ) ) {
1084                                         return true;
1085                                 }
1086                         }
1087                 }
1088                 return false;
1089         }
1090
1091         /**
1092          * Is this a talk page of some sort?
1093          * @return bool
1094          * @access public
1095          */
1096         function isTalkPage() {
1097                 return Namespace::isTalk( $this->getNamespace() );
1098         }
1099
1100         /**
1101          * Is this a .css or .js subpage of a user page?
1102          * @return bool
1103          * @access public
1104          */
1105         function isCssJsSubpage() {
1106                 return ( NS_USER == $this->mNamespace and preg_match("/\\.(css|js)$/", $this->mTextform ) );
1107         }
1108         /**
1109          * Is this a .css subpage of a user page?
1110          * @return bool
1111          * @access public
1112          */
1113         function isCssSubpage() {
1114                 return ( NS_USER == $this->mNamespace and preg_match("/\\.css$/", $this->mTextform ) );
1115         }
1116         /**
1117          * Is this a .js subpage of a user page?
1118          * @return bool
1119          * @access public
1120          */
1121         function isJsSubpage() {
1122                 return ( NS_USER == $this->mNamespace and preg_match("/\\.js$/", $this->mTextform ) );
1123         }
1124         /**
1125          * Protect css/js subpages of user pages: can $wgUser edit
1126          * this page?
1127          *
1128          * @return boolean
1129          * @todo XXX: this might be better using restrictions
1130          * @access public
1131          */
1132         function userCanEditCssJsSubpage() {
1133                 global $wgUser;
1134                 return ( $wgUser->isAllowed('editinterface') or preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1135         }
1136
1137         /**
1138          * Loads a string into mRestrictions array
1139          * @param string $res restrictions in string format
1140          * @access public
1141          */
1142         function loadRestrictions( $res ) {
1143                 foreach( explode( ':', trim( $res ) ) as $restrict ) {
1144                         $temp = explode( '=', trim( $restrict ) );
1145                         if(count($temp) == 1) {
1146                                 // old format should be treated as edit/move restriction
1147                                 $this->mRestrictions["edit"] = explode( ',', trim( $temp[0] ) );
1148                                 $this->mRestrictions["move"] = explode( ',', trim( $temp[0] ) );
1149                         } else {
1150                                 $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
1151                         }
1152                 }
1153                 $this->mRestrictionsLoaded = true;
1154         }
1155
1156         /**
1157          * Accessor/initialisation for mRestrictions
1158          * @param string $action action that permission needs to be checked for
1159          * @return array the array of groups allowed to edit this article
1160          * @access public
1161          */
1162         function getRestrictions($action) {
1163                 $id = $this->getArticleID();
1164                 if ( 0 == $id ) { return array(); }
1165
1166                 if ( ! $this->mRestrictionsLoaded ) {
1167                         $dbr =& wfGetDB( DB_SLAVE );
1168                         $res = $dbr->selectField( 'page', 'page_restrictions', 'page_id='.$id );
1169                         $this->loadRestrictions( $res );
1170                 }
1171                 if( isset( $this->mRestrictions[$action] ) ) {
1172                         return $this->mRestrictions[$action];
1173                 }
1174                 return array();
1175         }
1176
1177         /**
1178          * Is there a version of this page in the deletion archive?
1179          * @return int the number of archived revisions
1180          * @access public
1181          */
1182         function isDeleted() {
1183                 $fname = 'Title::isDeleted';
1184                 if ( $this->getNamespace() < 0 ) {
1185                         $n = 0;
1186                 } else {
1187                         $dbr =& wfGetDB( DB_SLAVE );
1188                         $n = $dbr->selectField( 'archive', 'COUNT(*)', array( 'ar_namespace' => $this->getNamespace(),
1189                                 'ar_title' => $this->getDBkey() ), $fname );
1190                 }
1191                 return (int)$n;
1192         }
1193
1194         /**
1195          * Get the article ID for this Title from the link cache,
1196          * adding it if necessary
1197          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select
1198          *      for update
1199          * @return int the ID
1200          * @access public
1201          */
1202         function getArticleID( $flags = 0 ) {
1203                 $linkCache =& LinkCache::singleton();
1204                 if ( $flags & GAID_FOR_UPDATE ) {
1205                         $oldUpdate = $linkCache->forUpdate( true );
1206                         $this->mArticleID = $linkCache->addLinkObj( $this );
1207                         $linkCache->forUpdate( $oldUpdate );
1208                 } else {
1209                         if ( -1 == $this->mArticleID ) {
1210                                 $this->mArticleID = $linkCache->addLinkObj( $this );
1211                         }
1212                 }
1213                 return $this->mArticleID;
1214         }
1215
1216         function getLatestRevID() {
1217                 if ($this->mLatestID !== false)
1218                         return $this->mLatestID;
1219
1220                 $db =& wfGetDB(DB_SLAVE);
1221                 return $this->mLatestID = $db->selectField( 'revision',
1222                         "max(rev_id)",
1223                         array('rev_page' => $this->getArticleID()),
1224                         'Title::getLatestRevID' );
1225         }
1226
1227         /**
1228          * This clears some fields in this object, and clears any associated
1229          * keys in the "bad links" section of the link cache.
1230          *
1231          * - This is called from Article::insertNewArticle() to allow
1232          * loading of the new page_id. It's also called from
1233          * Article::doDeleteArticle()
1234          *
1235          * @param int $newid the new Article ID
1236          * @access public
1237          */
1238         function resetArticleID( $newid ) {
1239                 $linkCache =& LinkCache::singleton();
1240                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
1241
1242                 if ( 0 == $newid ) { $this->mArticleID = -1; }
1243                 else { $this->mArticleID = $newid; }
1244                 $this->mRestrictionsLoaded = false;
1245                 $this->mRestrictions = array();
1246         }
1247
1248         /**
1249          * Updates page_touched for this page; called from LinksUpdate.php
1250          * @return bool true if the update succeded
1251          * @access public
1252          */
1253         function invalidateCache() {
1254                 global $wgUseFileCache;
1255
1256                 if ( wfReadOnly() ) {
1257                         return;
1258                 }
1259
1260                 $dbw =& wfGetDB( DB_MASTER );
1261                 $success = $dbw->update( 'page',
1262                         array( /* SET */
1263                                 'page_touched' => $dbw->timestamp()
1264                         ), array( /* WHERE */
1265                                 'page_namespace' => $this->getNamespace() ,
1266                                 'page_title' => $this->getDBkey()
1267                         ), 'Title::invalidateCache'
1268                 );
1269
1270                 if ($wgUseFileCache) {
1271                         $cache = new CacheManager($this);
1272                         @unlink($cache->fileCacheName());
1273                 }
1274
1275                 return $success;
1276         }
1277
1278         /**
1279          * Prefix some arbitrary text with the namespace or interwiki prefix
1280          * of this object
1281          *
1282          * @param string $name the text
1283          * @return string the prefixed text
1284          * @access private
1285          */
1286         /* private */ function prefix( $name ) {
1287                 global $wgContLang;
1288
1289                 $p = '';
1290                 if ( '' != $this->mInterwiki ) {
1291                         $p = $this->mInterwiki . ':';
1292                 }
1293                 if ( 0 != $this->mNamespace ) {
1294                         $p .= $wgContLang->getNsText( $this->mNamespace ) . ':';
1295                 }
1296                 return $p . $name;
1297         }
1298
1299         /**
1300          * Secure and split - main initialisation function for this object
1301          *
1302          * Assumes that mDbkeyform has been set, and is urldecoded
1303          * and uses underscores, but not otherwise munged.  This function
1304          * removes illegal characters, splits off the interwiki and
1305          * namespace prefixes, sets the other forms, and canonicalizes
1306          * everything.
1307          * @return bool true on success
1308          * @access private
1309          */
1310         /* private */ function secureAndSplit() {
1311                 global $wgContLang, $wgLocalInterwiki, $wgCapitalLinks;
1312                 $fname = 'Title::secureAndSplit';
1313
1314                 # Initialisation
1315                 static $rxTc = false;
1316                 if( !$rxTc ) {
1317                         # % is needed as well
1318                         $rxTc = '/[^' . Title::legalChars() . ']|%[0-9A-Fa-f]{2}/S';
1319                 }
1320
1321                 $this->mInterwiki = $this->mFragment = '';
1322                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
1323
1324                 # Clean up whitespace
1325                 #
1326                 $t = preg_replace( '/[ _]+/', '_', $this->mDbkeyform );
1327                 $t = trim( $t, '_' );
1328
1329                 if ( '' == $t ) {
1330                         return false;
1331                 }
1332
1333                 if( false !== strpos( $t, UTF8_REPLACEMENT ) ) {
1334                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
1335                         return false;
1336                 }
1337
1338                 $this->mDbkeyform = $t;
1339
1340                 # Initial colon indicates main namespace rather than specified default
1341                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
1342                 if ( ':' == $t{0} ) {
1343                         $this->mNamespace = NS_MAIN;
1344                         $t = substr( $t, 1 ); # remove the colon but continue processing
1345                 }
1346
1347                 # Namespace or interwiki prefix
1348                 $firstPass = true;
1349                 do {
1350                         if ( preg_match( "/^(.+?)_*:_*(.*)$/S", $t, $m ) ) {
1351                                 $p = $m[1];
1352                                 $lowerNs = strtolower( $p );
1353                                 if ( $ns = Namespace::getCanonicalIndex( $lowerNs ) ) {
1354                                         # Canonical namespace
1355                                         $t = $m[2];
1356                                         $this->mNamespace = $ns;
1357                                 } elseif ( $ns = $wgContLang->getNsIndex( $lowerNs )) {
1358                                         # Ordinary namespace
1359                                         $t = $m[2];
1360                                         $this->mNamespace = $ns;
1361                                 } elseif( $this->getInterwikiLink( $p ) ) {
1362                                         if( !$firstPass ) {
1363                                                 # Can't make a local interwiki link to an interwiki link.
1364                                                 # That's just crazy!
1365                                                 return false;
1366                                         }
1367
1368                                         # Interwiki link
1369                                         $t = $m[2];
1370                                         $this->mInterwiki = strtolower( $p );
1371
1372                                         # Redundant interwiki prefix to the local wiki
1373                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
1374                                                 if( $t == '' ) {
1375                                                         # Can't have an empty self-link
1376                                                         return false;
1377                                                 }
1378                                                 $this->mInterwiki = '';
1379                                                 $firstPass = false;
1380                                                 # Do another namespace split...
1381                                                 continue;
1382                                         }
1383
1384                                         # If there's an initial colon after the interwiki, that also
1385                                         # resets the default namespace
1386                                         if ( $t !== '' && $t[0] == ':' ) {
1387                                                 $this->mNamespace = NS_MAIN;
1388                                                 $t = substr( $t, 1 );
1389                                         }
1390                                 }
1391                                 # If there's no recognized interwiki or namespace,
1392                                 # then let the colon expression be part of the title.
1393                         }
1394                         break;
1395                 } while( true );
1396                 $r = $t;
1397
1398                 # We already know that some pages won't be in the database!
1399                 #
1400                 if ( '' != $this->mInterwiki || -1 == $this->mNamespace ) {
1401                         $this->mArticleID = 0;
1402                 }
1403                 $f = strstr( $r, '#' );
1404                 if ( false !== $f ) {
1405                         $this->mFragment = substr( $f, 1 );
1406                         $r = substr( $r, 0, strlen( $r ) - strlen( $f ) );
1407                         # remove whitespace again: prevents "Foo_bar_#"
1408                         # becoming "Foo_bar_"
1409                         $r = preg_replace( '/_*$/', '', $r );
1410                 }
1411
1412                 # Reject illegal characters.
1413                 #
1414                 if( preg_match( $rxTc, $r ) ) {
1415                         return false;
1416                 }
1417
1418                 /**
1419                  * Pages with "/./" or "/../" appearing in the URLs will
1420                  * often be unreachable due to the way web browsers deal
1421                  * with 'relative' URLs. Forbid them explicitly.
1422                  */
1423                 if ( strpos( $r, '.' ) !== false &&
1424                      ( $r === '.' || $r === '..' ||
1425                        strpos( $r, './' ) === 0  ||
1426                        strpos( $r, '../' ) === 0 ||
1427                        strpos( $r, '/./' ) !== false ||
1428                        strpos( $r, '/../' ) !== false ) )
1429                 {
1430                         return false;
1431                 }
1432
1433                 # We shouldn't need to query the DB for the size.
1434                 #$maxSize = $dbr->textFieldSize( 'page', 'page_title' );
1435                 if ( strlen( $r ) > 255 ) {
1436                         return false;
1437                 }
1438
1439                 /**
1440                  * Normally, all wiki links are forced to have
1441                  * an initial capital letter so [[foo]] and [[Foo]]
1442                  * point to the same place.
1443                  *
1444                  * Don't force it for interwikis, since the other
1445                  * site might be case-sensitive.
1446                  */
1447                 if( $wgCapitalLinks && $this->mInterwiki == '') {
1448                         $t = $wgContLang->ucfirst( $r );
1449                 } else {
1450                         $t = $r;
1451                 }
1452
1453                 /**
1454                  * Can't make a link to a namespace alone...
1455                  * "empty" local links can only be self-links
1456                  * with a fragment identifier.
1457                  */
1458                 if( $t == '' &&
1459                         $this->mInterwiki == '' &&
1460                         $this->mNamespace != NS_MAIN ) {
1461                         return false;
1462                 }
1463
1464                 # Fill fields
1465                 $this->mDbkeyform = $t;
1466                 $this->mUrlform = wfUrlencode( $t );
1467
1468                 $this->mTextform = str_replace( '_', ' ', $t );
1469
1470                 return true;
1471         }
1472
1473         /**
1474          * Get a Title object associated with the talk page of this article
1475          * @return Title the object for the talk page
1476          * @access public
1477          */
1478         function getTalkPage() {
1479                 return Title::makeTitle( Namespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1480         }
1481
1482         /**
1483          * Get a title object associated with the subject page of this
1484          * talk page
1485          *
1486          * @return Title the object for the subject page
1487          * @access public
1488          */
1489         function getSubjectPage() {
1490                 return Title::makeTitle( Namespace::getSubject( $this->getNamespace() ), $this->getDBkey() );
1491         }
1492
1493         /**
1494          * Get an array of Title objects linking to this Title
1495          * Also stores the IDs in the link cache.
1496          *
1497          * @param string $options may be FOR UPDATE
1498          * @return array the Title objects linking here
1499          * @access public
1500          */
1501         function getLinksTo( $options = '', $table = 'pagelinks', $prefix = 'pl' ) {
1502                 $linkCache =& LinkCache::singleton();
1503                 $id = $this->getArticleID();
1504
1505                 if ( $options ) {
1506                         $db =& wfGetDB( DB_MASTER );
1507                 } else {
1508                         $db =& wfGetDB( DB_SLAVE );
1509                 }
1510
1511                 $res = $db->select( array( 'page', $table ),
1512                         array( 'page_namespace', 'page_title', 'page_id' ),
1513                         array(
1514                                 "{$prefix}_from=page_id",
1515                                 "{$prefix}_namespace" => $this->getNamespace(),
1516                                 "{$prefix}_title"     => $this->getDbKey() ),
1517                         'Title::getLinksTo',
1518                         $options );
1519
1520                 $retVal = array();
1521                 if ( $db->numRows( $res ) ) {
1522                         while ( $row = $db->fetchObject( $res ) ) {
1523                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
1524                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj );
1525                                         $retVal[] = $titleObj;
1526                                 }
1527                         }
1528                 }
1529                 $db->freeResult( $res );
1530                 return $retVal;
1531         }
1532
1533         /**
1534          * Get an array of Title objects using this Title as a template
1535          * Also stores the IDs in the link cache.
1536          *
1537          * @param string $options may be FOR UPDATE
1538          * @return array the Title objects linking here
1539          * @access public
1540          */
1541         function getTemplateLinksTo( $options = '' ) {
1542                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
1543         }
1544
1545         /**
1546          * Get an array of Title objects referring to non-existent articles linked from this page
1547          *
1548          * @param string $options may be FOR UPDATE
1549          * @return array the Title objects
1550          * @access public
1551          */
1552         function getBrokenLinksFrom( $options = '' ) {
1553                 if ( $options ) {
1554                         $db =& wfGetDB( DB_MASTER );
1555                 } else {
1556                         $db =& wfGetDB( DB_SLAVE );
1557                 }
1558
1559                 $res = $db->safeQuery(
1560                           "SELECT pl_namespace, pl_title
1561                              FROM !
1562                         LEFT JOIN !
1563                                ON pl_namespace=page_namespace
1564                               AND pl_title=page_title
1565                             WHERE pl_from=?
1566                               AND page_namespace IS NULL
1567                                   !",
1568                         $db->tableName( 'pagelinks' ),
1569                         $db->tableName( 'page' ),
1570                         $this->getArticleId(),
1571                         $options );
1572
1573                 $retVal = array();
1574                 if ( $db->numRows( $res ) ) {
1575                         while ( $row = $db->fetchObject( $res ) ) {
1576                                 $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
1577                         }
1578                 }
1579                 $db->freeResult( $res );
1580                 return $retVal;
1581         }
1582
1583
1584         /**
1585          * Get a list of URLs to purge from the Squid cache when this
1586          * page changes
1587          *
1588          * @return array the URLs
1589          * @access public
1590          */
1591         function getSquidURLs() {
1592                 return array(
1593                         $this->getInternalURL(),
1594                         $this->getInternalURL( 'action=history' )
1595                 );
1596         }
1597
1598         /**
1599          * Move this page without authentication
1600          * @param Title &$nt the new page Title
1601          * @access public
1602          */
1603         function moveNoAuth( &$nt ) {
1604                 return $this->moveTo( $nt, false );
1605         }
1606
1607         /**
1608          * Check whether a given move operation would be valid.
1609          * Returns true if ok, or a message key string for an error message
1610          * if invalid. (Scarrrrry ugly interface this.)
1611          * @param Title &$nt the new title
1612          * @param bool $auth indicates whether $wgUser's permissions
1613          *      should be checked
1614          * @return mixed true on success, message name on failure
1615          * @access public
1616          */
1617         function isValidMoveOperation( &$nt, $auth = true ) {
1618                 global $wgUser;
1619                 if( !$this or !$nt ) {
1620                         return 'badtitletext';
1621                 }
1622                 if( $this->equals( $nt ) ) {
1623                         return 'selfmove';
1624                 }
1625                 if( !$this->isMovable() || !$nt->isMovable() ) {
1626                         return 'immobile_namespace';
1627                 }
1628
1629                 $oldid = $this->getArticleID();
1630                 $newid = $nt->getArticleID();
1631
1632                 if ( strlen( $nt->getDBkey() ) < 1 ) {
1633                         return 'articleexists';
1634                 }
1635                 if ( ( '' == $this->getDBkey() ) ||
1636                          ( !$oldid ) ||
1637                      ( '' == $nt->getDBkey() ) ) {
1638                         return 'badarticleerror';
1639                 }
1640
1641                 if ( $auth && (
1642                                 !$this->userCanEdit() || !$nt->userCanEdit() ||
1643                                 !$this->userCanMove() || !$nt->userCanMove() ) ) {
1644                         return 'protectedpage';
1645                 }
1646
1647                 # The move is allowed only if (1) the target doesn't exist, or
1648                 # (2) the target is a redirect to the source, and has no history
1649                 # (so we can undo bad moves right after they're done).
1650
1651                 if ( 0 != $newid ) { # Target exists; check for validity
1652                         if ( ! $this->isValidMoveTarget( $nt ) ) {
1653                                 return 'articleexists';
1654                         }
1655                 }
1656                 return true;
1657         }
1658
1659         /**
1660          * Move a title to a new location
1661          * @param Title &$nt the new title
1662          * @param bool $auth indicates whether $wgUser's permissions
1663          *      should be checked
1664          * @return mixed true on success, message name on failure
1665          * @access public
1666          */
1667         function moveTo( &$nt, $auth = true, $reason = '' ) {
1668                 $err = $this->isValidMoveOperation( $nt, $auth );
1669                 if( is_string( $err ) ) {
1670                         return $err;
1671                 }
1672
1673                 $pageid = $this->getArticleID();
1674                 if( $nt->exists() ) {
1675                         $this->moveOverExistingRedirect( $nt, $reason );
1676                         $pageCountChange = 0;
1677                 } else { # Target didn't exist, do normal move.
1678                         $this->moveToNewTitle( $nt, $reason );
1679                         $pageCountChange = 1;
1680                 }
1681                 $redirid = $this->getArticleID();
1682
1683                 # Fixing category links (those without piped 'alternate' names) to be sorted under the new title
1684                 $dbw =& wfGetDB( DB_MASTER );
1685                 $categorylinks = $dbw->tableName( 'categorylinks' );
1686                 $sql = "UPDATE $categorylinks SET cl_sortkey=" . $dbw->addQuotes( $nt->getPrefixedText() ) .
1687                         " WHERE cl_from=" . $dbw->addQuotes( $pageid ) .
1688                         " AND cl_sortkey=" . $dbw->addQuotes( $this->getPrefixedText() );
1689                 $dbw->query( $sql, 'SpecialMovepage::doSubmit' );
1690
1691                 # Update watchlists
1692
1693                 $oldnamespace = $this->getNamespace() & ~1;
1694                 $newnamespace = $nt->getNamespace() & ~1;
1695                 $oldtitle = $this->getDBkey();
1696                 $newtitle = $nt->getDBkey();
1697
1698                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
1699                         WatchedItem::duplicateEntries( $this, $nt );
1700                 }
1701
1702                 # Update search engine
1703                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
1704                 $u->doUpdate();
1705                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
1706                 $u->doUpdate();
1707
1708                 # Update site_stats
1709                 if ( $this->getNamespace() == NS_MAIN and $nt->getNamespace() != NS_MAIN ) {
1710                         # Moved out of main namespace
1711                         # not viewed, edited, removing
1712                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange);
1713                 } elseif ( $this->getNamespace() != NS_MAIN and $nt->getNamespace() == NS_MAIN ) {
1714                         # Moved into main namespace
1715                         # not viewed, edited, adding
1716                         $u = new SiteStatsUpdate( 0, 1, +1, $pageCountChange );
1717                 } elseif ( $pageCountChange ) {
1718                         # Added redirect
1719                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
1720                 } else{
1721                         $u = false;
1722                 }
1723                 if ( $u ) {
1724                         $u->doUpdate();
1725                 }
1726
1727                 global $wgUser;
1728                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
1729                 return true;
1730         }
1731
1732         /**
1733          * Move page to a title which is at present a redirect to the
1734          * source page
1735          *
1736          * @param Title &$nt the page to move to, which should currently
1737          *      be a redirect
1738          * @access private
1739          */
1740         function moveOverExistingRedirect( &$nt, $reason = '' ) {
1741                 global $wgUser, $wgUseSquid, $wgMwRedir;
1742                 $fname = 'Title::moveOverExistingRedirect';
1743                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
1744
1745                 if ( $reason ) {
1746                         $comment .= ": $reason";
1747                 }
1748
1749                 $now = wfTimestampNow();
1750                 $rand = wfRandom();
1751                 $newid = $nt->getArticleID();
1752                 $oldid = $this->getArticleID();
1753                 $dbw =& wfGetDB( DB_MASTER );
1754                 $linkCache =& LinkCache::singleton();
1755
1756                 # Delete the old redirect. We don't save it to history since
1757                 # by definition if we've got here it's rather uninteresting.
1758                 # We have to remove it so that the next step doesn't trigger
1759                 # a conflict on the unique namespace+title index...
1760                 $dbw->delete( 'page', array( 'page_id' => $newid ), $fname );
1761
1762                 # Save a null revision in the page's history notifying of the move
1763                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
1764                 $nullRevId = $nullRevision->insertOn( $dbw );
1765
1766                 # Change the name of the target page:
1767                 $dbw->update( 'page',
1768                         /* SET */ array(
1769                                 'page_touched'   => $dbw->timestamp($now),
1770                                 'page_namespace' => $nt->getNamespace(),
1771                                 'page_title'     => $nt->getDBkey(),
1772                                 'page_latest'    => $nullRevId,
1773                         ),
1774                         /* WHERE */ array( 'page_id' => $oldid ),
1775                         $fname
1776                 );
1777                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
1778
1779                 # Recreate the redirect, this time in the other direction.
1780                 $redirectText = $wgMwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
1781                 $redirectArticle = new Article( $this );
1782                 $newid = $redirectArticle->insertOn( $dbw );
1783                 $redirectRevision = new Revision( array(
1784                         'page'    => $newid,
1785                         'comment' => $comment,
1786                         'text'    => $redirectText ) );
1787                 $revid = $redirectRevision->insertOn( $dbw );
1788                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
1789                 $linkCache->clearLink( $this->getPrefixedDBkey() );
1790
1791                 # Log the move
1792                 $log = new LogPage( 'move' );
1793                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText() ) );
1794
1795                 # Now, we record the link from the redirect to the new title.
1796                 # It should have no other outgoing links...
1797                 $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), $fname );
1798                 $dbw->insert( 'pagelinks',
1799                         array(
1800                                 'pl_from'      => $newid,
1801                                 'pl_namespace' => $nt->getNamespace(),
1802                                 'pl_title'     => $nt->getDbKey() ),
1803                         $fname );
1804
1805                 # Purge squid
1806                 if ( $wgUseSquid ) {
1807                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
1808                         $u = new SquidUpdate( $urls );
1809                         $u->doUpdate();
1810                 }
1811         }
1812
1813         /**
1814          * Move page to non-existing title.
1815          * @param Title &$nt the new Title
1816          * @access private
1817          */
1818         function moveToNewTitle( &$nt, $reason = '' ) {
1819                 global $wgUser, $wgUseSquid;
1820                 global $wgMwRedir;
1821                 $fname = 'MovePageForm::moveToNewTitle';
1822                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
1823                 if ( $reason ) {
1824                         $comment .= ": $reason";
1825                 }
1826
1827                 $newid = $nt->getArticleID();
1828                 $oldid = $this->getArticleID();
1829                 $dbw =& wfGetDB( DB_MASTER );
1830                 $now = $dbw->timestamp();
1831                 $rand = wfRandom();
1832                 $linkCache =& LinkCache::singleton();
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                 # Rename cur entry
1839                 $dbw->update( 'page',
1840                         /* SET */ array(
1841                                 'page_touched'   => $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
1850                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
1851
1852                 # Insert redirect
1853                 $redirectText = $wgMwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
1854                 $redirectArticle = new Article( $this );
1855                 $newid = $redirectArticle->insertOn( $dbw );
1856                 $redirectRevision = new Revision( array(
1857                         'page'    => $newid,
1858                         'comment' => $comment,
1859                         'text'    => $redirectText ) );
1860                 $revid = $redirectRevision->insertOn( $dbw );
1861                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
1862                 $linkCache->clearLink( $this->getPrefixedDBkey() );
1863
1864                 # Log the move
1865                 $log = new LogPage( 'move' );
1866                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText()) );
1867
1868                 # Purge caches as per article creation
1869                 Article::onArticleCreate( $nt );
1870
1871                 # Record the just-created redirect's linking to the page
1872                 $dbw->insert( 'pagelinks',
1873                         array(
1874                                 'pl_from'      => $newid,
1875                                 'pl_namespace' => $nt->getNamespace(),
1876                                 'pl_title'     => $nt->getDBkey() ),
1877                         $fname );
1878
1879                 # Non-existent target may have had broken links to it; these must
1880                 # now be touched to update link coloring.
1881                 $nt->touchLinks();
1882
1883                 # Purge old title from squid
1884                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
1885                 $titles = $nt->getLinksTo();
1886                 if ( $wgUseSquid ) {
1887                         $urls = $this->getSquidURLs();
1888                         foreach ( $titles as $linkTitle ) {
1889                                 $urls[] = $linkTitle->getInternalURL();
1890                         }
1891                         $u = new SquidUpdate( $urls );
1892                         $u->doUpdate();
1893                 }
1894         }
1895
1896         /**
1897          * Checks if $this can be moved to a given Title
1898          * - Selects for update, so don't call it unless you mean business
1899          *
1900          * @param Title &$nt the new title to check
1901          * @access public
1902          */
1903         function isValidMoveTarget( $nt ) {
1904
1905                 $fname = 'Title::isValidMoveTarget';
1906                 $dbw =& wfGetDB( DB_MASTER );
1907
1908                 # Is it a redirect?
1909                 $id  = $nt->getArticleID();
1910                 $obj = $dbw->selectRow( array( 'page', 'revision', 'text'),
1911                         array( 'page_is_redirect','old_text','old_flags' ),
1912                         array( 'page_id' => $id, 'page_latest=rev_id', 'rev_text_id=old_id' ),
1913                         $fname, 'FOR UPDATE' );
1914
1915                 if ( !$obj || 0 == $obj->page_is_redirect ) {
1916                         # Not a redirect
1917                         return false;
1918                 }
1919                 $text = Revision::getRevisionText( $obj );
1920
1921                 # Does the redirect point to the source?
1922                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
1923                         $redirTitle = Title::newFromText( $m[1] );
1924                         if( !is_object( $redirTitle ) ||
1925                                 $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() ) {
1926                                 return false;
1927                         }
1928                 } else {
1929                         # Fail safe
1930                         return false;
1931                 }
1932
1933                 # Does the article have a history?
1934                 $row = $dbw->selectRow( array( 'page', 'revision'),
1935                         array( 'rev_id' ),
1936                         array( 'page_namespace' => $nt->getNamespace(),
1937                                 'page_title' => $nt->getDBkey(),
1938                                 'page_id=rev_page AND page_latest != rev_id'
1939                         ), $fname, 'FOR UPDATE'
1940                 );
1941
1942                 # Return true if there was no history
1943                 return $row === false;
1944         }
1945
1946         /**
1947          * Create a redirect; fails if the title already exists; does
1948          * not notify RC
1949          *
1950          * @param Title $dest the destination of the redirect
1951          * @param string $comment the comment string describing the move
1952          * @return bool true on success
1953          * @access public
1954          */
1955         function createRedirect( $dest, $comment ) {
1956                 global $wgUser;
1957                 if ( $this->getArticleID() ) {
1958                         return false;
1959                 }
1960
1961                 $fname = 'Title::createRedirect';
1962                 $dbw =& wfGetDB( DB_MASTER );
1963
1964                 $article = new Article( $this );
1965                 $newid = $article->insertOn( $dbw );
1966                 $revision = new Revision( array(
1967                         'page'      => $newid,
1968                         'comment'   => $comment,
1969                         'text'      => "#REDIRECT [[" . $dest->getPrefixedText() . "]]\n",
1970                         ) );
1971                 $revisionId = $revision->insertOn( $dbw );
1972                 $article->updateRevisionOn( $dbw, $revision, 0 );
1973
1974                 # Link table
1975                 $dbw->insert( 'pagelinks',
1976                         array(
1977                                 'pl_from'      => $newid,
1978                                 'pl_namespace' => $dest->getNamespace(),
1979                                 'pl_title'     => $dest->getDbKey()
1980                         ), $fname
1981                 );
1982
1983                 Article::onArticleCreate( $this );
1984                 return true;
1985         }
1986
1987         /**
1988          * Get categories to which this Title belongs and return an array of
1989          * categories' names.
1990          *
1991          * @return array an array of parents in the form:
1992          *      $parent => $currentarticle
1993          * @access public
1994          */
1995         function getParentCategories() {
1996                 global $wgContLang,$wgUser;
1997
1998                 $titlekey = $this->getArticleId();
1999                 $dbr =& wfGetDB( DB_SLAVE );
2000                 $categorylinks = $dbr->tableName( 'categorylinks' );
2001
2002                 # NEW SQL
2003                 $sql = "SELECT * FROM $categorylinks"
2004                      ." WHERE cl_from='$titlekey'"
2005                          ." AND cl_from <> '0'"
2006                          ." ORDER BY cl_sortkey";
2007
2008                 $res = $dbr->query ( $sql ) ;
2009
2010                 if($dbr->numRows($res) > 0) {
2011                         while ( $x = $dbr->fetchObject ( $res ) )
2012                                 //$data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to);
2013                                 $data[$wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to] = $this->getFullText();
2014                         $dbr->freeResult ( $res ) ;
2015                 } else {
2016                         $data = '';
2017                 }
2018                 return $data;
2019         }
2020
2021         /**
2022          * Get a tree of parent categories
2023          * @param array $children an array with the children in the keys, to check for circular refs
2024          * @return array
2025          * @access public
2026          */
2027         function getParentCategoryTree( $children = array() ) {
2028                 $parents = $this->getParentCategories();
2029
2030                 if($parents != '') {
2031                         foreach($parents as $parent => $current) {
2032                                 if ( array_key_exists( $parent, $children ) ) {
2033                                         # Circular reference
2034                                         $stack[$parent] = array();
2035                                 } else {
2036                                         $nt = Title::newFromText($parent);
2037                                         $stack[$parent] = $nt->getParentCategoryTree( $children + array($parent => 1) );
2038                                 }
2039                         }
2040                         return $stack;
2041                 } else {
2042                         return array();
2043                 }
2044         }
2045
2046
2047         /**
2048          * Get an associative array for selecting this title from
2049          * the "page" table
2050          *
2051          * @return array
2052          * @access public
2053          */
2054         function pageCond() {
2055                 return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
2056         }
2057
2058         /**
2059          * Get the revision ID of the previous revision
2060          *
2061          * @param integer $revision  Revision ID. Get the revision that was before this one.
2062          * @return interger $oldrevision|false
2063          */
2064         function getPreviousRevisionID( $revision ) {
2065                 $dbr =& wfGetDB( DB_SLAVE );
2066                 return $dbr->selectField( 'revision', 'rev_id',
2067                         'rev_page=' . intval( $this->getArticleId() ) .
2068                         ' AND rev_id<' . intval( $revision ) . ' ORDER BY rev_id DESC' );
2069         }
2070
2071         /**
2072          * Get the revision ID of the next revision
2073          *
2074          * @param integer $revision  Revision ID. Get the revision that was after this one.
2075          * @return interger $oldrevision|false
2076          */
2077         function getNextRevisionID( $revision ) {
2078                 $dbr =& wfGetDB( DB_SLAVE );
2079                 return $dbr->selectField( 'revision', 'rev_id',
2080                         'rev_page=' . intval( $this->getArticleId() ) .
2081                         ' AND rev_id>' . intval( $revision ) . ' ORDER BY rev_id' );
2082         }
2083
2084         /**
2085          * Compare with another title.
2086          *
2087          * @param Title $title
2088          * @return bool
2089          */
2090         function equals( $title ) {
2091                 return $this->getInterwiki() == $title->getInterwiki()
2092                         && $this->getNamespace() == $title->getNamespace()
2093                         && $this->getDbkey() == $title->getDbkey();
2094         }
2095
2096         /**
2097          * Check if page exists
2098          * @return bool
2099          */
2100         function exists() {
2101                 return $this->getArticleId() != 0;
2102         }
2103
2104         /**
2105          * Should a link should be displayed as a known link, just based on its title?
2106          *
2107          * Currently, a self-link with a fragment and special pages are in
2108          * this category. Special pages never exist in the database.
2109          */
2110         function isAlwaysKnown() {
2111                 return  $this->isExternal() || ( 0 == $this->mNamespace && "" == $this->mDbkeyform )
2112                   || NS_SPECIAL == $this->mNamespace;
2113         }
2114
2115         /**
2116          * Update page_touched timestamps on pages linking to this title.
2117          * In principal, this could be backgrounded and could also do squid
2118          * purging.
2119          */
2120         function touchLinks() {
2121                 $fname = 'Title::touchLinks';
2122
2123                 $dbw =& wfGetDB( DB_MASTER );
2124
2125                 $res = $dbw->select( 'pagelinks',
2126                         array( 'pl_from' ),
2127                         array(
2128                                 'pl_namespace' => $this->getNamespace(),
2129                                 'pl_title'     => $this->getDbKey() ),
2130                         $fname );
2131
2132                 $toucharr = array();
2133                 while( $row = $dbw->fetchObject( $res ) ) {
2134                         $toucharr[] = $row->pl_from;
2135                 }
2136                 $dbw->freeResult( $res );
2137
2138                 if( $this->getNamespace() == NS_CATEGORY ) {
2139                         // Categories show up in a separate set of links as well
2140                         $res = $dbw->select( 'categorylinks',
2141                                 array( 'cl_from' ),
2142                                 array( 'cl_to' => $this->getDbKey() ),
2143                                 $fname );
2144                         while( $row = $dbw->fetchObject( $res ) ) {
2145                                 $toucharr[] = $row->cl_from;
2146                         }
2147                         $dbw->freeResult( $res );
2148                 }
2149
2150                 if (!count($toucharr))
2151                         return;
2152                 $dbw->update( 'page', /* SET */ array( 'page_touched' => $dbw->timestamp() ),
2153                                                         /* WHERE */ array( 'page_id' => $toucharr ),$fname);
2154         }
2155
2156         function trackbackURL() {
2157                 global $wgTitle, $wgScriptPath, $wgServer;
2158
2159                 return "$wgServer$wgScriptPath/trackback.php?article="
2160                         . htmlspecialchars(urlencode($wgTitle->getPrefixedDBkey()));
2161         }
2162
2163         function trackbackRDF() {
2164                 $url = htmlspecialchars($this->getFullURL());
2165                 $title = htmlspecialchars($this->getText());
2166                 $tburl = $this->trackbackURL();
2167
2168                 return "
2169 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
2170          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
2171          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
2172 <rdf:Description
2173    rdf:about=\"$url\"
2174    dc:identifier=\"$url\"
2175    dc:title=\"$title\"
2176    trackback:ping=\"$tburl\" />
2177 </rdf:RDF>";
2178         }
2179 }
2180 ?>