includes/Title.php

   1 <?php
   2 /**
   3  * See title.txt
   4  *
   5  * @package MediaWiki
   6  */
   7
   8 /** */
   9 require_once( 'normal/UtfNormal.php' );
  10
  11 define ( 'GAID_FOR_UPDATE', 1 );
  12
  13 # Title::newFromTitle maintains a cache to avoid
  14 # expensive re-normalization of commonly used titles.
  15 # On a batch operation this can become a memory leak
  16 # if not bounded. After hitting this many titles,
  17 # reset the cache.
  18 define( 'MW_TITLECACHE_MAX', 1000 );
  19
  20 /**
  21  * Title class
  22  * - Represents a title, which may contain an interwiki designation or namespace
  23  * - Can fetch various kinds of data from the database, albeit inefficiently.
  24  *
  25  * @package MediaWiki
  26  */
  27 class Title {
  28         /**
  29          * Static cache variables
  30          */
  31         static private $titleCache=array();
  32         static private $interwikiCache=array();
  33
  34
  35         /**
  36          * All member variables should be considered private
  37          * Please use the accessor functions
  38          */
  39
  40          /**#@+
  41          * @private
  42          */
  43
  44         var $mTextform;           # Text form (spaces not underscores) of the main part
  45         var $mUrlform;            # URL-encoded form of the main part
  46         var $mDbkeyform;          # Main part with underscores
  47         var $mNamespace;          # Namespace index, i.e. one of the NS_xxxx constants
  48         var $mInterwiki;          # Interwiki prefix (or null string)
  49         var $mFragment;           # Title fragment (i.e. the bit after the #)
  50         var $mArticleID;          # Article ID, fetched from the link cache on demand
  51         var $mLatestID;         # ID of most recent revision
  52         var $mRestrictions;       # Array of groups allowed to edit this article
  53                                 # Only null or "sysop" are supported
  54         var $mRestrictionsLoaded; # Boolean for initialisation on demand
  55         var $mPrefixedText;       # Text form including namespace/interwiki, initialised on demand
  56         var $mDefaultNamespace;   # Namespace index when there is no namespace
  57                             # Zero except in {{transclusion}} tags
  58         var $mWatched;      # Is $wgUser watching this page? NULL if unfilled, accessed through userIsWatching()
  59         /**#@-*/
  60
  61
  62         /**
  63          * Constructor
  64          * @private
  65          */
  66         /* private */ function Title() {
  67                 $this->mInterwiki = $this->mUrlform =
  68                 $this->mTextform = $this->mDbkeyform = '';
  69                 $this->mArticleID = -1;
  70                 $this->mNamespace = NS_MAIN;
  71                 $this->mRestrictionsLoaded = false;
  72                 $this->mRestrictions = array();
  73                 # Dont change the following, NS_MAIN is hardcoded in several place
  74                 # See bug #696
  75                 $this->mDefaultNamespace = NS_MAIN;
  76                 $this->mWatched = NULL;
  77                 $this->mLatestID = false;
  78         }
  79
  80         /**
  81          * Create a new Title from a prefixed DB key
  82          * @param string $key The database key, which has underscores
  83          *      instead of spaces, possibly including namespace and
  84          *      interwiki prefixes
  85          * @return Title the new object, or NULL on an error
  86          * @static
  87          * @access public
  88          */
  89         /* static */ function newFromDBkey( $key ) {
  90                 $t = new Title();
  91                 $t->mDbkeyform = $key;
  92                 if( $t->secureAndSplit() )
  93                         return $t;
  94                 else
  95                         return NULL;
  96         }
  97
  98         /**
  99          * Create a new Title from text, such as what one would
 100          * find in a link. Decodes any HTML entities in the text.
 101          *
 102          * @param string $text the link text; spaces, prefixes,
 103          *      and an initial ':' indicating the main namespace
 104          *      are accepted
 105          * @param int $defaultNamespace the namespace to use if
 106          *      none is specified by a prefix
 107          * @return Title the new object, or NULL on an error
 108          * @static
 109          * @access public
 110          */
 111         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 112                 $fname = 'Title::newFromText';
 113
 114                 if( is_object( $text ) ) {
 115                         throw new MWException( 'Title::newFromText given an object' );
 116                 }
 117
 118                 /**
 119                  * Wiki pages often contain multiple links to the same page.
 120                  * Title normalization and parsing can become expensive on
 121                  * pages with many links, so we can save a little time by
 122                  * caching them.
 123                  *
 124                  * In theory these are value objects and won't get changed...
 125                  */
 126                 if( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 127                         return Title::$titleCache[$text];
 128                 }
 129
 130                 /**
 131                  * Convert things like &eacute; &#257; or &#x3017; into real text...
 132                  */
 133                 $filteredText = Sanitizer::decodeCharReferences( $text );
 134
 135                 $t = new Title();
 136                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 137                 $t->mDefaultNamespace = $defaultNamespace;
 138
 139                 static $cachedcount = 0 ;
 140                 if( $t->secureAndSplit() ) {
 141                         if( $defaultNamespace == NS_MAIN ) {
 142                                 if( $cachedcount >= MW_TITLECACHE_MAX ) {
 143                                         # Avoid memory leaks on mass operations...
 144                                         Title::$titleCache = array();
 145                                         $cachedcount=0;
 146                                 }
 147                                 $cachedcount++;
 148                                 Title::$titleCache[$text] =& $t;
 149                         }
 150                         return $t;
 151                 } else {
 152                         $ret = NULL;
 153                         return $ret;
 154                 }
 155         }
 156
 157         /**
 158          * Create a new Title from URL-encoded text. Ensures that
 159          * the given title's length does not exceed the maximum.
 160          * @param string $url the title, as might be taken from a URL
 161          * @return Title the new object, or NULL on an error
 162          * @static
 163          * @access public
 164          */
 165         function newFromURL( $url ) {
 166                 global $wgLegalTitleChars;
 167                 $t = new Title();
 168
 169                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 170                 # but some URLs used it as a space replacement and they still come
 171                 # from some external search tools.
 172                 if ( strpos( $wgLegalTitleChars, '+' ) === false ) {
 173                         $url = str_replace( '+', ' ', $url );
 174                 }
 175
 176                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 177                 if( $t->secureAndSplit() ) {
 178                         return $t;
 179                 } else {
 180                         return NULL;
 181                 }
 182         }
 183
 184         /**
 185          * Create a new Title from an article ID
 186          *
 187          * @todo This is inefficiently implemented, the page row is requested
 188          *       but not used for anything else
 189          *
 190          * @param int $id the page_id corresponding to the Title to create
 191          * @return Title the new object, or NULL on an error
 192          * @access public
 193          * @static
 194          */
 195         function newFromID( $id ) {
 196                 $fname = 'Title::newFromID';
 197                 $dbr =& wfGetDB( DB_SLAVE );
 198                 $row = $dbr->selectRow( 'page', array( 'page_namespace', 'page_title' ),
 199                         array( 'page_id' => $id ), $fname );
 200                 if ( $row !== false ) {
 201                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 202                 } else {
 203                         $title = NULL;
 204                 }
 205                 return $title;
 206         }
 207
 208         /**
 209          * Make an array of titles from an array of IDs
 210          */
 211         function newFromIDs( $ids ) {
 212                 $dbr =& wfGetDB( DB_SLAVE );
 213                 $res = $dbr->select( 'page', array( 'page_namespace', 'page_title' ),
 214                         'page_id IN (' . $dbr->makeList( $ids ) . ')', __METHOD__ );
 215
 216                 $titles = array();
 217                 while ( $row = $dbr->fetchObject( $res ) ) {
 218                         $titles[] = Title::makeTitle( $row->page_namespace, $row->page_title );
 219                 }
 220                 return $titles;
 221         }
 222
 223         /**
 224          * Create a new Title from a namespace index and a DB key.
 225          * It's assumed that $ns and $title are *valid*, for instance when
 226          * they came directly from the database or a special page name.
 227          * For convenience, spaces are converted to underscores so that
 228          * eg user_text fields can be used directly.
 229          *
 230          * @param int $ns the namespace of the article
 231          * @param string $title the unprefixed database key form
 232          * @return Title the new object
 233          * @static
 234          * @access public
 235          */
 236         public static function &makeTitle( $ns, $title ) {
 237                 $t = new Title();
 238                 $t->mInterwiki = '';
 239                 $t->mFragment = '';
 240                 $t->mNamespace = intval( $ns );
 241                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 242                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 243                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 244                 $t->mTextform = str_replace( '_', ' ', $title );
 245                 return $t;
 246         }
 247
 248         /**
 249          * Create a new Title from a namespace index and a DB key.
 250          * The parameters will be checked for validity, which is a bit slower
 251          * than makeTitle() but safer for user-provided data.
 252          *
 253          * @param int $ns the namespace of the article
 254          * @param string $title the database key form
 255          * @return Title the new object, or NULL on an error
 256          * @static
 257          * @access public
 258          */
 259         public static function makeTitleSafe( $ns, $title ) {
 260                 $t = new Title();
 261                 $t->mDbkeyform = Title::makeName( $ns, $title );
 262                 if( $t->secureAndSplit() ) {
 263                         return $t;
 264                 } else {
 265                         return NULL;
 266                 }
 267         }
 268
 269         /**
 270          * Create a new Title for the Main Page
 271          *
 272          * @static
 273          * @return Title the new object
 274          * @access public
 275          */
 276         public static function newMainPage() {
 277                 return Title::newFromText( wfMsgForContent( 'mainpage' ) );
 278         }
 279
 280         /**
 281          * Create a new Title for a redirect
 282          * @param string $text the redirect title text
 283          * @return Title the new object, or NULL if the text is not a
 284          *      valid redirect
 285          * @static
 286          * @access public
 287          */
 288         public static function newFromRedirect( $text ) {
 289                 $mwRedir = MagicWord::get( 'redirect' );
 290                 $rt = NULL;
 291                 if ( $mwRedir->matchStart( $text ) ) {
 292                         if ( preg_match( '/\[{2}(.*?)(?:\||\]{2})/', $text, $m ) ) {
 293                                 # categories are escaped using : for example one can enter:
 294                                 # #REDIRECT [[:Category:Music]]. Need to remove it.
 295                                 if ( substr($m[1],0,1) == ':') {
 296                                         # We don't want to keep the ':'
 297                                         $m[1] = substr( $m[1], 1 );
 298                                 }
 299
 300                                 $rt = Title::newFromText( $m[1] );
 301                                 # Disallow redirects to Special:Userlogout
 302                                 if ( !is_null($rt) && $rt->getNamespace() == NS_SPECIAL && preg_match( '/^Userlogout/i', $rt->getText() ) ) {
 303                                         $rt = NULL;
 304                                 }
 305                         }
 306                 }
 307                 return $rt;
 308         }
 309
 310 #----------------------------------------------------------------------------
 311 #       Static functions
 312 #----------------------------------------------------------------------------
 313
 314         /**
 315          * Get the prefixed DB key associated with an ID
 316          * @param int $id the page_id of the article
 317          * @return Title an object representing the article, or NULL
 318          *      if no such article was found
 319          * @static
 320          * @access public
 321          */
 322         function nameOf( $id ) {
 323                 $fname = 'Title::nameOf';
 324                 $dbr =& wfGetDB( DB_SLAVE );
 325
 326                 $s = $dbr->selectRow( 'page', array( 'page_namespace','page_title' ),  array( 'page_id' => $id ), $fname );
 327                 if ( $s === false ) { return NULL; }
 328
 329                 $n = Title::makeName( $s->page_namespace, $s->page_title );
 330                 return $n;
 331         }
 332
 333         /**
 334          * Get a regex character class describing the legal characters in a link
 335          * @return string the list of characters, not delimited
 336          * @static
 337          * @access public
 338          */
 339         public static function legalChars() {
 340                 global $wgLegalTitleChars;
 341                 return $wgLegalTitleChars;
 342         }
 343
 344         /**
 345          * Get a string representation of a title suitable for
 346          * including in a search index
 347          *
 348          * @param int $ns a namespace index
 349          * @param string $title text-form main part
 350          * @return string a stripped-down title string ready for the
 351          *      search index
 352          */
 353         /* static */ function indexTitle( $ns, $title ) {
 354                 global $wgContLang;
 355
 356                 $lc = SearchEngine::legalSearchChars() . '&#;';
 357                 $t = $wgContLang->stripForSearch( $title );
 358                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 359                 $t = strtolower( $t );
 360
 361                 # Handle 's, s'
 362                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 363                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 364
 365                 $t = preg_replace( "/\\s+/", ' ', $t );
 366
 367                 if ( $ns == NS_IMAGE ) {
 368                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 369                 }
 370                 return trim( $t );
 371         }
 372
 373         /*
 374          * Make a prefixed DB key from a DB key and a namespace index
 375          * @param int $ns numerical representation of the namespace
 376          * @param string $title the DB key form the title
 377          * @return string the prefixed form of the title
 378          */
 379         public static function makeName( $ns, $title ) {
 380                 global $wgContLang;
 381
 382                 $n = $wgContLang->getNsText( $ns );
 383                 return $n == '' ? $title : "$n:$title";
 384         }
 385
 386         /**
 387          * Returns the URL associated with an interwiki prefix
 388          * @param string $key the interwiki prefix (e.g. "MeatBall")
 389          * @return the associated URL, containing "$1", which should be
 390          *      replaced by an article title
 391          * @static (arguably)
 392          * @access public
 393          */
 394         function getInterwikiLink( $key )  {
 395                 global $wgMemc, $wgInterwikiExpiry;
 396                 global $wgInterwikiCache;
 397                 $fname = 'Title::getInterwikiLink';
 398
 399                 $key = strtolower( $key );
 400
 401                 $k = wfMemcKey( 'interwiki', $key );
 402                 if( array_key_exists( $k, Title::$interwikiCache ) ) {
 403                         return Title::$interwikiCache[$k]->iw_url;
 404                 }
 405
 406                 if ($wgInterwikiCache) {
 407                         return Title::getInterwikiCached( $key );
 408                 }
 409
 410                 $s = $wgMemc->get( $k );
 411                 # Ignore old keys with no iw_local
 412                 if( $s && isset( $s->iw_local ) && isset($s->iw_trans)) {
 413                         Title::$interwikiCache[$k] = $s;
 414                         return $s->iw_url;
 415                 }
 416
 417                 $dbr =& wfGetDB( DB_SLAVE );
 418                 $res = $dbr->select( 'interwiki',
 419                         array( 'iw_url', 'iw_local', 'iw_trans' ),
 420                         array( 'iw_prefix' => $key ), $fname );
 421                 if( !$res ) {
 422                         return '';
 423                 }
 424
 425                 $s = $dbr->fetchObject( $res );
 426                 if( !$s ) {
 427                         # Cache non-existence: create a blank object and save it to memcached
 428                         $s = (object)false;
 429                         $s->iw_url = '';
 430                         $s->iw_local = 0;
 431                         $s->iw_trans = 0;
 432                 }
 433                 $wgMemc->set( $k, $s, $wgInterwikiExpiry );
 434                 Title::$interwikiCache[$k] = $s;
 435
 436                 return $s->iw_url;
 437         }
 438
 439         /**
 440          * Fetch interwiki prefix data from local cache in constant database
 441          *
 442          * More logic is explained in DefaultSettings
 443          *
 444          * @return string URL of interwiki site
 445          * @access public
 446          */
 447         function getInterwikiCached( $key ) {
 448                 global $wgInterwikiCache, $wgInterwikiScopes, $wgInterwikiFallbackSite;
 449                 static $db, $site;
 450
 451                 if (!$db)
 452                         $db=dba_open($wgInterwikiCache,'r','cdb');
 453                 /* Resolve site name */
 454                 if ($wgInterwikiScopes>=3 and !$site) {
 455                         $site = dba_fetch('__sites:' . wfWikiID(), $db);
 456                         if ($site=="")
 457                                 $site = $wgInterwikiFallbackSite;
 458                 }
 459                 $value = dba_fetch( wfMemcKey( $key ), $db);
 460                 if ($value=='' and $wgInterwikiScopes>=3) {
 461                         /* try site-level */
 462                         $value = dba_fetch("_{$site}:{$key}", $db);
 463                 }
 464                 if ($value=='' and $wgInterwikiScopes>=2) {
 465                         /* try globals */
 466                         $value = dba_fetch("__global:{$key}", $db);
 467                 }
 468                 if ($value=='undef')
 469                         $value='';
 470                 $s = (object)false;
 471                 $s->iw_url = '';
 472                 $s->iw_local = 0;
 473                 $s->iw_trans = 0;
 474                 if ($value!='') {
 475                         list($local,$url)=explode(' ',$value,2);
 476                         $s->iw_url=$url;
 477                         $s->iw_local=(int)$local;
 478                 }
 479                 Title::$interwikiCache[wfMemcKey( 'interwiki', $key )] = $s;
 480                 return $s->iw_url;
 481         }
 482         /**
 483          * Determine whether the object refers to a page within
 484          * this project.
 485          *
 486          * @return bool TRUE if this is an in-project interwiki link
 487          *      or a wikilink, FALSE otherwise
 488          * @access public
 489          */
 490         function isLocal() {
 491                 if ( $this->mInterwiki != '' ) {
 492                         # Make sure key is loaded into cache
 493                         $this->getInterwikiLink( $this->mInterwiki );
 494                         $k = wfMemcKey( 'interwiki', $this->mInterwiki );
 495                         return (bool)(Title::$interwikiCache[$k]->iw_local);
 496                 } else {
 497                         return true;
 498                 }
 499         }
 500
 501         /**
 502          * Determine whether the object refers to a page within
 503          * this project and is transcludable.
 504          *
 505          * @return bool TRUE if this is transcludable
 506          * @access public
 507          */
 508         function isTrans() {
 509                 if ($this->mInterwiki == '')
 510                         return false;
 511                 # Make sure key is loaded into cache
 512                 $this->getInterwikiLink( $this->mInterwiki );
 513                 $k = wfMemcKey( 'interwiki', $this->mInterwiki );
 514                 return (bool)(Title::$interwikiCache[$k]->iw_trans);
 515         }
 516
 517         /**
 518          * Update the page_touched field for an array of title objects
 519          * @todo Inefficient unless the IDs are already loaded into the
 520          *      link cache
 521          * @param array $titles an array of Title objects to be touched
 522          * @param string $timestamp the timestamp to use instead of the
 523          *      default current time
 524          * @static
 525          * @access public
 526          */
 527         function touchArray( $titles, $timestamp = '' ) {
 528
 529                 if ( count( $titles ) == 0 ) {
 530                         return;
 531                 }
 532                 $dbw =& wfGetDB( DB_MASTER );
 533                 if ( $timestamp == '' ) {
 534                         $timestamp = $dbw->timestamp();
 535                 }
 536                 /*
 537                 $page = $dbw->tableName( 'page' );
 538                 $sql = "UPDATE $page SET page_touched='{$timestamp}' WHERE page_id IN (";
 539                 $first = true;
 540
 541                 foreach ( $titles as $title ) {
 542                         if ( $wgUseFileCache ) {
 543                                 $cm = new CacheManager($title);
 544                                 @unlink($cm->fileCacheName());
 545                         }
 546
 547                         if ( ! $first ) {
 548                                 $sql .= ',';
 549                         }
 550                         $first = false;
 551                         $sql .= $title->getArticleID();
 552                 }
 553                 $sql .= ')';
 554                 if ( ! $first ) {
 555                         $dbw->query( $sql, 'Title::touchArray' );
 556                 }
 557                 */
 558                 // hack hack hack -- brion 2005-07-11. this was unfriendly to db.
 559                 // do them in small chunks:
 560                 $fname = 'Title::touchArray';
 561                 foreach( $titles as $title ) {
 562                         $dbw->update( 'page',
 563                                 array( 'page_touched' => $timestamp ),
 564                                 array(
 565                                         'page_namespace' => $title->getNamespace(),
 566                                         'page_title'     => $title->getDBkey() ),
 567                                 $fname );
 568                 }
 569         }
 570
 571 #----------------------------------------------------------------------------
 572 #       Other stuff
 573 #----------------------------------------------------------------------------
 574
 575         /** Simple accessors */
 576         /**
 577          * Get the text form (spaces not underscores) of the main part
 578          * @return string
 579          * @access public
 580          */
 581         function getText() { return $this->mTextform; }
 582         /**
 583          * Get the URL-encoded form of the main part
 584          * @return string
 585          * @access public
 586          */
 587         function getPartialURL() { return $this->mUrlform; }
 588         /**
 589          * Get the main part with underscores
 590          * @return string
 591          * @access public
 592          */
 593         function getDBkey() { return $this->mDbkeyform; }
 594         /**
 595          * Get the namespace index, i.e. one of the NS_xxxx constants
 596          * @return int
 597          * @access public
 598          */
 599         function getNamespace() { return $this->mNamespace; }
 600         /**
 601          * Get the namespace text
 602          * @return string
 603          * @access public
 604          */
 605         function getNsText() {
 606                 global $wgContLang;
 607                 return $wgContLang->getNsText( $this->mNamespace );
 608         }
 609         /**
 610          * Get the namespace text of the subject (rather than talk) page
 611          * @return string
 612          * @access public
 613          */
 614         function getSubjectNsText() {
 615                 global $wgContLang;
 616                 return $wgContLang->getNsText( Namespace::getSubject( $this->mNamespace ) );
 617         }
 618
 619         /**
 620          * Get the namespace text of the talk page
 621          * @return string
 622          */
 623         function getTalkNsText() {
 624                 global $wgContLang;
 625                 return( $wgContLang->getNsText( Namespace::getTalk( $this->mNamespace ) ) );
 626         }
 627
 628         /**
 629          * Could this title have a corresponding talk page?
 630          * @return bool
 631          */
 632         function canTalk() {
 633                 return( Namespace::canTalk( $this->mNamespace ) );
 634         }
 635
 636         /**
 637          * Get the interwiki prefix (or null string)
 638          * @return string
 639          * @access public
 640          */
 641         function getInterwiki() { return $this->mInterwiki; }
 642         /**
 643          * Get the Title fragment (i.e. the bit after the #)
 644          * @return string
 645          * @access public
 646          */
 647         function getFragment() { return $this->mFragment; }
 648         /**
 649          * Get the default namespace index, for when there is no namespace
 650          * @return int
 651          * @access public
 652          */
 653         function getDefaultNamespace() { return $this->mDefaultNamespace; }
 654
 655         /**
 656          * Get title for search index
 657          * @return string a stripped-down title string ready for the
 658          *      search index
 659          */
 660         function getIndexTitle() {
 661                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 662         }
 663
 664         /**
 665          * Get the prefixed database key form
 666          * @return string the prefixed title, with underscores and
 667          *      any interwiki and namespace prefixes
 668          * @access public
 669          */
 670         function getPrefixedDBkey() {
 671                 $s = $this->prefix( $this->mDbkeyform );
 672                 $s = str_replace( ' ', '_', $s );
 673                 return $s;
 674         }
 675
 676         /**
 677          * Get the prefixed title with spaces.
 678          * This is the form usually used for display
 679          * @return string the prefixed title, with spaces
 680          * @access public
 681          */
 682         function getPrefixedText() {
 683                 if ( empty( $this->mPrefixedText ) ) { // FIXME: bad usage of empty() ?
 684                         $s = $this->prefix( $this->mTextform );
 685                         $s = str_replace( '_', ' ', $s );
 686                         $this->mPrefixedText = $s;
 687                 }
 688                 return $this->mPrefixedText;
 689         }
 690
 691         /**
 692          * Get the prefixed title with spaces, plus any fragment
 693          * (part beginning with '#')
 694          * @return string the prefixed title, with spaces and
 695          *      the fragment, including '#'
 696          * @access public
 697          */
 698         function getFullText() {
 699                 $text = $this->getPrefixedText();
 700                 if( '' != $this->mFragment ) {
 701                         $text .= '#' . $this->mFragment;
 702                 }
 703                 return $text;
 704         }
 705
 706         /**
 707          * Get the base name, i.e. the leftmost parts before the /
 708          * @return string Base name
 709          */
 710         function getBaseText() {
 711                 global $wgNamespacesWithSubpages;
 712                 if( isset( $wgNamespacesWithSubpages[ $this->mNamespace ] ) && $wgNamespacesWithSubpages[ $this->mNamespace ] ) {
 713                         $parts = explode( '/', $this->getText() );
 714                         # Don't discard the real title if there's no subpage involved
 715                         if( count( $parts ) > 1 )
 716                                 unset( $parts[ count( $parts ) - 1 ] );
 717                         return implode( '/', $parts );
 718                 } else {
 719                         return $this->getText();
 720                 }
 721         }
 722
 723         /**
 724          * Get the lowest-level subpage name, i.e. the rightmost part after /
 725          * @return string Subpage name
 726          */
 727         function getSubpageText() {
 728                 global $wgNamespacesWithSubpages;
 729                 if( isset( $wgNamespacesWithSubpages[ $this->mNamespace ] ) && $wgNamespacesWithSubpages[ $this->mNamespace ] ) {
 730                         $parts = explode( '/', $this->mTextform );
 731                         return( $parts[ count( $parts ) - 1 ] );
 732                 } else {
 733                         return( $this->mTextform );
 734                 }
 735         }
 736
 737         /**
 738          * Get a URL-encoded form of the subpage text
 739          * @return string URL-encoded subpage name
 740          */
 741         function getSubpageUrlForm() {
 742                 $text = $this->getSubpageText();
 743                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
 744                 $text = str_replace( '%28', '(', str_replace( '%29', ')', $text ) ); # Clean up the URL; per below, this might not be safe
 745                 return( $text );
 746         }
 747
 748         /**
 749          * Get a URL-encoded title (not an actual URL) including interwiki
 750          * @return string the URL-encoded form
 751          * @access public
 752          */
 753         function getPrefixedURL() {
 754                 $s = $this->prefix( $this->mDbkeyform );
 755                 $s = str_replace( ' ', '_', $s );
 756
 757                 $s = wfUrlencode ( $s ) ;
 758
 759                 # Cleaning up URL to make it look nice -- is this safe?
 760                 $s = str_replace( '%28', '(', $s );
 761                 $s = str_replace( '%29', ')', $s );
 762
 763                 return $s;
 764         }
 765
 766         /**
 767          * Get a real URL referring to this title, with interwiki link and
 768          * fragment
 769          *
 770          * @param string $query an optional query string, not used
 771          *      for interwiki links
 772          * @return string the URL
 773          * @access public
 774          */
 775         function getFullURL( $query = '' ) {
 776                 global $wgContLang, $wgServer, $wgRequest;
 777
 778                 if ( '' == $this->mInterwiki ) {
 779                         $url = $this->getLocalUrl( $query );
 780
 781                         // Ugly quick hack to avoid duplicate prefixes (bug 4571 etc)
 782                         // Correct fix would be to move the prepending elsewhere.
 783                         if ($wgRequest->getVal('action') != 'render') {
 784                                 $url = $wgServer . $url;
 785                         }
 786                 } else {
 787                         $baseUrl = $this->getInterwikiLink( $this->mInterwiki );
 788
 789                         $namespace = $wgContLang->getNsText( $this->mNamespace );
 790                         if ( '' != $namespace ) {
 791                                 # Can this actually happen? Interwikis shouldn't be parsed.
 792                                 $namespace .= ':';
 793                         }
 794                         $url = str_replace( '$1', $namespace . $this->mUrlform, $baseUrl );
 795                         if( $query != '' ) {
 796                                 if( false === strpos( $url, '?' ) ) {
 797                                         $url .= '?';
 798                                 } else {
 799                                         $url .= '&';
 800                                 }
 801                                 $url .= $query;
 802                         }
 803                 }
 804
 805                 # Finally, add the fragment.
 806                 if ( '' != $this->mFragment ) {
 807                         $url .= '#' . $this->mFragment;
 808                 }
 809
 810                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
 811                 return $url;
 812         }
 813
 814         /**
 815          * Get a URL with no fragment or server name.  If this page is generated
 816          * with action=render, $wgServer is prepended.
 817          * @param string $query an optional query string; if not specified,
 818          *      $wgArticlePath will be used.
 819          * @return string the URL
 820          * @access public
 821          */
 822         function getLocalURL( $query = '' ) {
 823                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
 824
 825                 if ( $this->isExternal() ) {
 826                         $url = $this->getFullURL();
 827                         if ( $query ) {
 828                                 // This is currently only used for edit section links in the
 829                                 // context of interwiki transclusion. In theory we should
 830                                 // append the query to the end of any existing query string,
 831                                 // but interwiki transclusion is already broken in that case.
 832                                 $url .= "?$query";
 833                         }
 834                 } else {
 835                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 836                         if ( $query == '' ) {
 837                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
 838                         } else {
 839                                 global $wgActionPaths;
 840                                 $url = false;
 841                                 if( !empty( $wgActionPaths ) &&
 842                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
 843                                 {
 844                                         $action = urldecode( $matches[2] );
 845                                         if( isset( $wgActionPaths[$action] ) ) {
 846                                                 $query = $matches[1];
 847                                                 if( isset( $matches[4] ) ) $query .= $matches[4];
 848                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
 849                                                 if( $query != '' ) $url .= '?' . $query;
 850                                         }
 851                                 }
 852                                 if ( $url === false ) {
 853                                         if ( $query == '-' ) {
 854                                                 $query = '';
 855                                         }
 856                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
 857                                 }
 858                         }
 859
 860                         // FIXME: this causes breakage in various places when we
 861                         // actually expected a local URL and end up with dupe prefixes.
 862                         if ($wgRequest->getVal('action') == 'render') {
 863                                 $url = $wgServer . $url;
 864                         }
 865                 }
 866                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
 867                 return $url;
 868         }
 869
 870         /**
 871          * Get an HTML-escaped version of the URL form, suitable for
 872          * using in a link, without a server name or fragment
 873          * @param string $query an optional query string
 874          * @return string the URL
 875          * @access public
 876          */
 877         function escapeLocalURL( $query = '' ) {
 878                 return htmlspecialchars( $this->getLocalURL( $query ) );
 879         }
 880
 881         /**
 882          * Get an HTML-escaped version of the URL form, suitable for
 883          * using in a link, including the server name and fragment
 884          *
 885          * @return string the URL
 886          * @param string $query an optional query string
 887          * @access public
 888          */
 889         function escapeFullURL( $query = '' ) {
 890                 return htmlspecialchars( $this->getFullURL( $query ) );
 891         }
 892
 893         /**
 894          * Get the URL form for an internal link.
 895          * - Used in various Squid-related code, in case we have a different
 896          * internal hostname for the server from the exposed one.
 897          *
 898          * @param string $query an optional query string
 899          * @return string the URL
 900          * @access public
 901          */
 902         function getInternalURL( $query = '' ) {
 903                 global $wgInternalServer;
 904                 $url = $wgInternalServer . $this->getLocalURL( $query );
 905                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
 906                 return $url;
 907         }
 908
 909         /**
 910          * Get the edit URL for this Title
 911          * @return string the URL, or a null string if this is an
 912          *      interwiki link
 913          * @access public
 914          */
 915         function getEditURL() {
 916                 if ( '' != $this->mInterwiki ) { return ''; }
 917                 $s = $this->getLocalURL( 'action=edit' );
 918
 919                 return $s;
 920         }
 921
 922         /**
 923          * Get the HTML-escaped displayable text form.
 924          * Used for the title field in <a> tags.
 925          * @return string the text, including any prefixes
 926          * @access public
 927          */
 928         function getEscapedText() {
 929                 return htmlspecialchars( $this->getPrefixedText() );
 930         }
 931
 932         /**
 933          * Is this Title interwiki?
 934          * @return boolean
 935          * @access public
 936          */
 937         function isExternal() { return ( '' != $this->mInterwiki ); }
 938
 939         /**
 940          * Is this page "semi-protected" - the *only* protection is autoconfirm?
 941          *
 942          * @param string Action to check (default: edit)
 943          * @return bool
 944          */
 945         function isSemiProtected( $action = 'edit' ) {
 946                 $restrictions = $this->getRestrictions( $action );
 947                 # We do a full compare because this could be an array
 948                 foreach( $restrictions as $restriction ) {
 949                         if( strtolower( $restriction ) != 'autoconfirmed' ) {
 950                                 return( false );
 951                         }
 952                 }
 953                 return( true );
 954         }
 955
 956         /**
 957          * Does the title correspond to a protected article?
 958          * @param string $what the action the page is protected from,
 959          *      by default checks move and edit
 960          * @return boolean
 961          * @access public
 962          */
 963         function isProtected( $action = '' ) {
 964                 global $wgRestrictionLevels;
 965                 if ( -1 == $this->mNamespace ) { return true; }
 966
 967                 if( $action == 'edit' || $action == '' ) {
 968                         $r = $this->getRestrictions( 'edit' );
 969                         foreach( $wgRestrictionLevels as $level ) {
 970                                 if( in_array( $level, $r ) && $level != '' ) {
 971                                         return( true );
 972                                 }
 973                         }
 974                 }
 975
 976                 if( $action == 'move' || $action == '' ) {
 977                         $r = $this->getRestrictions( 'move' );
 978                         foreach( $wgRestrictionLevels as $level ) {
 979                                 if( in_array( $level, $r ) && $level != '' ) {
 980                                         return( true );
 981                                 }
 982                         }
 983                 }
 984
 985                 return false;
 986         }
 987
 988         /**
 989          * Is $wgUser is watching this page?
 990          * @return boolean
 991          * @access public
 992          */
 993         function userIsWatching() {
 994                 global $wgUser;
 995
 996                 if ( is_null( $this->mWatched ) ) {
 997                         if ( -1 == $this->mNamespace || 0 == $wgUser->getID()) {
 998                                 $this->mWatched = false;
 999                         } else {
1000                                 $this->mWatched = $wgUser->isWatched( $this );
1001                         }
1002                 }
1003                 return $this->mWatched;
1004         }
1005
1006         /**
1007          * Can $wgUser perform $action this page?
1008          * @param string $action action that permission needs to be checked for
1009          * @return boolean
1010          * @private
1011          */
1012         function userCan($action) {
1013                 $fname = 'Title::userCan';
1014                 wfProfileIn( $fname );
1015
1016                 global $wgUser;
1017
1018                 $result = null;
1019                 wfRunHooks( 'userCan', array( &$this, &$wgUser, $action, &$result ) );
1020                 if ( $result !== null ) {
1021                         wfProfileOut( $fname );
1022                         return $result;
1023                 }
1024
1025                 if( NS_SPECIAL == $this->mNamespace ) {
1026                         wfProfileOut( $fname );
1027                         return false;
1028                 }
1029                 // XXX: This is the code that prevents unprotecting a page in NS_MEDIAWIKI
1030                 // from taking effect -ævar
1031                 if( NS_MEDIAWIKI == $this->mNamespace &&
1032                     !$wgUser->isAllowed('editinterface') ) {
1033                         wfProfileOut( $fname );
1034                         return false;
1035                 }
1036
1037                 if( $this->mDbkeyform == '_' ) {
1038                         # FIXME: Is this necessary? Shouldn't be allowed anyway...
1039                         wfProfileOut( $fname );
1040                         return false;
1041                 }
1042
1043                 # protect css/js subpages of user pages
1044                 # XXX: this might be better using restrictions
1045                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssJsSubpage() from working
1046                 if( NS_USER == $this->mNamespace
1047                         && preg_match("/\\.(css|js)$/", $this->mTextform )
1048                         && !$wgUser->isAllowed('editinterface')
1049                         && !preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) ) {
1050                         wfProfileOut( $fname );
1051                         return false;
1052                 }
1053
1054                 foreach( $this->getRestrictions($action) as $right ) {
1055                         // Backwards compatibility, rewrite sysop -> protect
1056                         if ( $right == 'sysop' ) {
1057                                 $right = 'protect';
1058                         }
1059                         if( '' != $right && !$wgUser->isAllowed( $right ) ) {
1060                                 wfProfileOut( $fname );
1061                                 return false;
1062                         }
1063                 }
1064
1065                 if( $action == 'move' &&
1066                         !( $this->isMovable() && $wgUser->isAllowed( 'move' ) ) ) {
1067                         wfProfileOut( $fname );
1068                         return false;
1069                 }
1070
1071                 if( $action == 'create' ) {
1072                         if( (  $this->isTalkPage() && !$wgUser->isAllowed( 'createtalk' ) ) ||
1073                                 ( !$this->isTalkPage() && !$wgUser->isAllowed( 'createpage' ) ) ) {
1074                                 wfProfileOut( $fname );
1075                                 return false;
1076                         }
1077                 }
1078
1079                 wfProfileOut( $fname );
1080                 return true;
1081         }
1082
1083         /**
1084          * Can $wgUser edit this page?
1085          * @return boolean
1086          * @access public
1087          */
1088         function userCanEdit() {
1089                 return $this->userCan('edit');
1090         }
1091
1092         /**
1093          * Can $wgUser create this page?
1094          * @return boolean
1095          * @access public
1096          */
1097         function userCanCreate() {
1098                 return $this->userCan('create');
1099         }
1100
1101         /**
1102          * Can $wgUser move this page?
1103          * @return boolean
1104          * @access public
1105          */
1106         function userCanMove() {
1107                 return $this->userCan('move');
1108         }
1109
1110         /**
1111          * Would anybody with sufficient privileges be able to move this page?
1112          * Some pages just aren't movable.
1113          *
1114          * @return boolean
1115          * @access public
1116          */
1117         function isMovable() {
1118                 return Namespace::isMovable( $this->getNamespace() )
1119                         && $this->getInterwiki() == '';
1120         }
1121
1122         /**
1123          * Can $wgUser read this page?
1124          * @return boolean
1125          * @access public
1126          */
1127         function userCanRead() {
1128                 global $wgUser;
1129
1130                 $result = null;
1131                 wfRunHooks( 'userCan', array( &$this, &$wgUser, 'read', &$result ) );
1132                 if ( $result !== null ) {
1133                         return $result;
1134                 }
1135
1136                 if( $wgUser->isAllowed('read') ) {
1137                         return true;
1138                 } else {
1139                         global $wgWhitelistRead;
1140
1141                         /** If anon users can create an account,
1142                             they need to reach the login page first! */
1143                         if( $wgUser->isAllowed( 'createaccount' )
1144                             && $this->getNamespace() == NS_SPECIAL
1145                             && $this->getText() == 'Userlogin' ) {
1146                                 return true;
1147                         }
1148
1149                         /** some pages are explicitly allowed */
1150                         $name = $this->getPrefixedText();
1151                         if( $wgWhitelistRead && in_array( $name, $wgWhitelistRead ) ) {
1152                                 return true;
1153                         }
1154
1155                         # Compatibility with old settings
1156                         if( $wgWhitelistRead && $this->getNamespace() == NS_MAIN ) {
1157                                 if( in_array( ':' . $name, $wgWhitelistRead ) ) {
1158                                         return true;
1159                                 }
1160                         }
1161                 }
1162                 return false;
1163         }
1164
1165         /**
1166          * Is this a talk page of some sort?
1167          * @return bool
1168          * @access public
1169          */
1170         function isTalkPage() {
1171                 return Namespace::isTalk( $this->getNamespace() );
1172         }
1173
1174         /**
1175          * Is this a .css or .js subpage of a user page?
1176          * @return bool
1177          * @access public
1178          */
1179         function isCssJsSubpage() {
1180                 return ( NS_USER == $this->mNamespace and preg_match("/\\.(css|js)$/", $this->mTextform ) );
1181         }
1182         /**
1183          * Is this a *valid* .css or .js subpage of a user page?
1184          * Check that the corresponding skin exists
1185          */
1186         function isValidCssJsSubpage() {
1187                 if ( $this->isCssJsSubpage() ) {
1188                         $skinNames = Skin::getSkinNames();
1189                         return array_key_exists( $this->getSkinFromCssJsSubpage(), $skinNames );
1190                 } else {
1191                         return false;
1192                 }
1193         }
1194         /**
1195          * Trim down a .css or .js subpage title to get the corresponding skin name
1196          */
1197         function getSkinFromCssJsSubpage() {
1198                 $subpage = explode( '/', $this->mTextform );
1199                 $subpage = $subpage[ count( $subpage ) - 1 ];
1200                 return( str_replace( array( '.css', '.js' ), array( '', '' ), $subpage ) );
1201         }
1202         /**
1203          * Is this a .css subpage of a user page?
1204          * @return bool
1205          * @access public
1206          */
1207         function isCssSubpage() {
1208                 return ( NS_USER == $this->mNamespace and preg_match("/\\.css$/", $this->mTextform ) );
1209         }
1210         /**
1211          * Is this a .js subpage of a user page?
1212          * @return bool
1213          * @access public
1214          */
1215         function isJsSubpage() {
1216                 return ( NS_USER == $this->mNamespace and preg_match("/\\.js$/", $this->mTextform ) );
1217         }
1218         /**
1219          * Protect css/js subpages of user pages: can $wgUser edit
1220          * this page?
1221          *
1222          * @return boolean
1223          * @todo XXX: this might be better using restrictions
1224          * @access public
1225          */
1226         function userCanEditCssJsSubpage() {
1227                 global $wgUser;
1228                 return ( $wgUser->isAllowed('editinterface') or preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1229         }
1230
1231         /**
1232          * Loads a string into mRestrictions array
1233          * @param string $res restrictions in string format
1234          * @access public
1235          */
1236         function loadRestrictions( $res ) {
1237                 foreach( explode( ':', trim( $res ) ) as $restrict ) {
1238                         $temp = explode( '=', trim( $restrict ) );
1239                         if(count($temp) == 1) {
1240                                 // old format should be treated as edit/move restriction
1241                                 $this->mRestrictions["edit"] = explode( ',', trim( $temp[0] ) );
1242                                 $this->mRestrictions["move"] = explode( ',', trim( $temp[0] ) );
1243                         } else {
1244                                 $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
1245                         }
1246                 }
1247                 $this->mRestrictionsLoaded = true;
1248         }
1249
1250         /**
1251          * Accessor/initialisation for mRestrictions
1252          * @param string $action action that permission needs to be checked for
1253          * @return array the array of groups allowed to edit this article
1254          * @access public
1255          */
1256         function getRestrictions($action) {
1257                 $id = $this->getArticleID();
1258                 if ( 0 == $id ) { return array(); }
1259
1260                 if ( ! $this->mRestrictionsLoaded ) {
1261                         $dbr =& wfGetDB( DB_SLAVE );
1262                         $res = $dbr->selectField( 'page', 'page_restrictions', 'page_id='.$id );
1263                         $this->loadRestrictions( $res );
1264                 }
1265                 if( isset( $this->mRestrictions[$action] ) ) {
1266                         return $this->mRestrictions[$action];
1267                 }
1268                 return array();
1269         }
1270
1271         /**
1272          * Is there a version of this page in the deletion archive?
1273          * @return int the number of archived revisions
1274          * @access public
1275          */
1276         function isDeleted() {
1277                 $fname = 'Title::isDeleted';
1278                 if ( $this->getNamespace() < 0 ) {
1279                         $n = 0;
1280                 } else {
1281                         $dbr =& wfGetDB( DB_SLAVE );
1282                         $n = $dbr->selectField( 'archive', 'COUNT(*)', array( 'ar_namespace' => $this->getNamespace(),
1283                                 'ar_title' => $this->getDBkey() ), $fname );
1284                         if( $this->getNamespace() == NS_IMAGE ) {
1285                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
1286                                         array( 'fa_name' => $this->getDBkey() ), $fname );
1287                         }
1288                 }
1289                 return (int)$n;
1290         }
1291
1292         /**
1293          * Get the article ID for this Title from the link cache,
1294          * adding it if necessary
1295          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select
1296          *      for update
1297          * @return int the ID
1298          * @access public
1299          */
1300         function getArticleID( $flags = 0 ) {
1301                 $linkCache =& LinkCache::singleton();
1302                 if ( $flags & GAID_FOR_UPDATE ) {
1303                         $oldUpdate = $linkCache->forUpdate( true );
1304                         $this->mArticleID = $linkCache->addLinkObj( $this );
1305                         $linkCache->forUpdate( $oldUpdate );
1306                 } else {
1307                         if ( -1 == $this->mArticleID ) {
1308                                 $this->mArticleID = $linkCache->addLinkObj( $this );
1309                         }
1310                 }
1311                 return $this->mArticleID;
1312         }
1313
1314         function getLatestRevID() {
1315                 if ($this->mLatestID !== false)
1316                         return $this->mLatestID;
1317
1318                 $db =& wfGetDB(DB_SLAVE);
1319                 return $this->mLatestID = $db->selectField( 'revision',
1320                         "max(rev_id)",
1321                         array('rev_page' => $this->getArticleID()),
1322                         'Title::getLatestRevID' );
1323         }
1324
1325         /**
1326          * This clears some fields in this object, and clears any associated
1327          * keys in the "bad links" section of the link cache.
1328          *
1329          * - This is called from Article::insertNewArticle() to allow
1330          * loading of the new page_id. It's also called from
1331          * Article::doDeleteArticle()
1332          *
1333          * @param int $newid the new Article ID
1334          * @access public
1335          */
1336         function resetArticleID( $newid ) {
1337                 $linkCache =& LinkCache::singleton();
1338                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
1339
1340                 if ( 0 == $newid ) { $this->mArticleID = -1; }
1341                 else { $this->mArticleID = $newid; }
1342                 $this->mRestrictionsLoaded = false;
1343                 $this->mRestrictions = array();
1344         }
1345
1346         /**
1347          * Updates page_touched for this page; called from LinksUpdate.php
1348          * @return bool true if the update succeded
1349          * @access public
1350          */
1351         function invalidateCache() {
1352                 global $wgUseFileCache;
1353
1354                 if ( wfReadOnly() ) {
1355                         return;
1356                 }
1357
1358                 $dbw =& wfGetDB( DB_MASTER );
1359                 $success = $dbw->update( 'page',
1360                         array( /* SET */
1361                                 'page_touched' => $dbw->timestamp()
1362                         ), array( /* WHERE */
1363                                 'page_namespace' => $this->getNamespace() ,
1364                                 'page_title' => $this->getDBkey()
1365                         ), 'Title::invalidateCache'
1366                 );
1367
1368                 if ($wgUseFileCache) {
1369                         $cache = new CacheManager($this);
1370                         @unlink($cache->fileCacheName());
1371                 }
1372
1373                 return $success;
1374         }
1375
1376         /**
1377          * Prefix some arbitrary text with the namespace or interwiki prefix
1378          * of this object
1379          *
1380          * @param string $name the text
1381          * @return string the prefixed text
1382          * @private
1383          */
1384         /* private */ function prefix( $name ) {
1385                 global $wgContLang;
1386
1387                 $p = '';
1388                 if ( '' != $this->mInterwiki ) {
1389                         $p = $this->mInterwiki . ':';
1390                 }
1391                 if ( 0 != $this->mNamespace ) {
1392                         $p .= $wgContLang->getNsText( $this->mNamespace ) . ':';
1393                 }
1394                 return $p . $name;
1395         }
1396
1397         /**
1398          * Secure and split - main initialisation function for this object
1399          *
1400          * Assumes that mDbkeyform has been set, and is urldecoded
1401          * and uses underscores, but not otherwise munged.  This function
1402          * removes illegal characters, splits off the interwiki and
1403          * namespace prefixes, sets the other forms, and canonicalizes
1404          * everything.
1405          * @return bool true on success
1406          * @private
1407          */
1408         /* private */ function secureAndSplit() {
1409                 global $wgContLang, $wgLocalInterwiki, $wgCapitalLinks;
1410                 $fname = 'Title::secureAndSplit';
1411
1412                 # Initialisation
1413                 static $rxTc = false;
1414                 if( !$rxTc ) {
1415                         # % is needed as well
1416                         $rxTc = '/[^' . Title::legalChars() . ']|%[0-9A-Fa-f]{2}/S';
1417                 }
1418
1419                 $this->mInterwiki = $this->mFragment = '';
1420                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
1421
1422                 # Clean up whitespace
1423                 #
1424                 $t = preg_replace( '/[ _]+/', '_', $this->mDbkeyform );
1425                 $t = trim( $t, '_' );
1426
1427                 if ( '' == $t ) {
1428                         return false;
1429                 }
1430
1431                 if( false !== strpos( $t, UTF8_REPLACEMENT ) ) {
1432                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
1433                         return false;
1434                 }
1435
1436                 $this->mDbkeyform = $t;
1437
1438                 # Initial colon indicates main namespace rather than specified default
1439                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
1440                 if ( ':' == $t{0} ) {
1441                         $this->mNamespace = NS_MAIN;
1442                         $t = substr( $t, 1 ); # remove the colon but continue processing
1443                 }
1444
1445                 # Namespace or interwiki prefix
1446                 $firstPass = true;
1447                 do {
1448                         if ( preg_match( "/^(.+?)_*:_*(.*)$/S", $t, $m ) ) {
1449                                 $p = $m[1];
1450                                 $lowerNs = strtolower( $p );
1451                                 if ( $ns = Namespace::getCanonicalIndex( $lowerNs ) ) {
1452                                         # Canonical namespace
1453                                         $t = $m[2];
1454                                         $this->mNamespace = $ns;
1455                                 } elseif ( $ns = $wgContLang->getNsIndex( $lowerNs )) {
1456                                         # Ordinary namespace
1457                                         $t = $m[2];
1458                                         $this->mNamespace = $ns;
1459                                 } elseif( $this->getInterwikiLink( $p ) ) {
1460                                         if( !$firstPass ) {
1461                                                 # Can't make a local interwiki link to an interwiki link.
1462                                                 # That's just crazy!
1463                                                 return false;
1464                                         }
1465
1466                                         # Interwiki link
1467                                         $t = $m[2];
1468                                         $this->mInterwiki = strtolower( $p );
1469
1470                                         # Redundant interwiki prefix to the local wiki
1471                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
1472                                                 if( $t == '' ) {
1473                                                         # Can't have an empty self-link
1474                                                         return false;
1475                                                 }
1476                                                 $this->mInterwiki = '';
1477                                                 $firstPass = false;
1478                                                 # Do another namespace split...
1479                                                 continue;
1480                                         }
1481
1482                                         # If there's an initial colon after the interwiki, that also
1483                                         # resets the default namespace
1484                                         if ( $t !== '' && $t[0] == ':' ) {
1485                                                 $this->mNamespace = NS_MAIN;
1486                                                 $t = substr( $t, 1 );
1487                                         }
1488                                 }
1489                                 # If there's no recognized interwiki or namespace,
1490                                 # then let the colon expression be part of the title.
1491                         }
1492                         break;
1493                 } while( true );
1494                 $r = $t;
1495
1496                 # We already know that some pages won't be in the database!
1497                 #
1498                 if ( '' != $this->mInterwiki || -1 == $this->mNamespace ) {
1499                         $this->mArticleID = 0;
1500                 }
1501                 $f = strstr( $r, '#' );
1502                 if ( false !== $f ) {
1503                         $this->mFragment = substr( $f, 1 );
1504                         $r = substr( $r, 0, strlen( $r ) - strlen( $f ) );
1505                         # remove whitespace again: prevents "Foo_bar_#"
1506                         # becoming "Foo_bar_"
1507                         $r = preg_replace( '/_*$/', '', $r );
1508                 }
1509
1510                 # Reject illegal characters.
1511                 #
1512                 if( preg_match( $rxTc, $r ) ) {
1513                         return false;
1514                 }
1515
1516                 /**
1517                  * Pages with "/./" or "/../" appearing in the URLs will
1518                  * often be unreachable due to the way web browsers deal
1519                  * with 'relative' URLs. Forbid them explicitly.
1520                  */
1521                 if ( strpos( $r, '.' ) !== false &&
1522                      ( $r === '.' || $r === '..' ||
1523                        strpos( $r, './' ) === 0  ||
1524                        strpos( $r, '../' ) === 0 ||
1525                        strpos( $r, '/./' ) !== false ||
1526                        strpos( $r, '/../' ) !== false ) )
1527                 {
1528                         return false;
1529                 }
1530
1531                 # We shouldn't need to query the DB for the size.
1532                 #$maxSize = $dbr->textFieldSize( 'page', 'page_title' );
1533                 if ( strlen( $r ) > 255 ) {
1534                         return false;
1535                 }
1536
1537                 /**
1538                  * Normally, all wiki links are forced to have
1539                  * an initial capital letter so [[foo]] and [[Foo]]
1540                  * point to the same place.
1541                  *
1542                  * Don't force it for interwikis, since the other
1543                  * site might be case-sensitive.
1544                  */
1545                 if( $wgCapitalLinks && $this->mInterwiki == '') {
1546                         $t = $wgContLang->ucfirst( $r );
1547                 } else {
1548                         $t = $r;
1549                 }
1550
1551                 /**
1552                  * Can't make a link to a namespace alone...
1553                  * "empty" local links can only be self-links
1554                  * with a fragment identifier.
1555                  */
1556                 if( $t == '' &&
1557                         $this->mInterwiki == '' &&
1558                         $this->mNamespace != NS_MAIN ) {
1559                         return false;
1560                 }
1561
1562                 // Any remaining initial :s are illegal.
1563                 if ( $t !== '' && ':' == $t{0} ) {
1564                         return false;
1565                 }
1566
1567                 # Fill fields
1568                 $this->mDbkeyform = $t;
1569                 $this->mUrlform = wfUrlencode( $t );
1570
1571                 $this->mTextform = str_replace( '_', ' ', $t );
1572
1573                 return true;
1574         }
1575
1576         /**
1577          * Get a Title object associated with the talk page of this article
1578          * @return Title the object for the talk page
1579          * @access public
1580          */
1581         function getTalkPage() {
1582                 return Title::makeTitle( Namespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1583         }
1584
1585         /**
1586          * Get a title object associated with the subject page of this
1587          * talk page
1588          *
1589          * @return Title the object for the subject page
1590          * @access public
1591          */
1592         function getSubjectPage() {
1593                 return Title::makeTitle( Namespace::getSubject( $this->getNamespace() ), $this->getDBkey() );
1594         }
1595
1596         /**
1597          * Get an array of Title objects linking to this Title
1598          * Also stores the IDs in the link cache.
1599          *
1600          * WARNING: do not use this function on arbitrary user-supplied titles!
1601          * On heavily-used templates it will max out the memory.
1602          *
1603          * @param string $options may be FOR UPDATE
1604          * @return array the Title objects linking here
1605          * @access public
1606          */
1607         function getLinksTo( $options = '', $table = 'pagelinks', $prefix = 'pl' ) {
1608                 $linkCache =& LinkCache::singleton();
1609                 $id = $this->getArticleID();
1610
1611                 if ( $options ) {
1612                         $db =& wfGetDB( DB_MASTER );
1613                 } else {
1614                         $db =& wfGetDB( DB_SLAVE );
1615                 }
1616
1617                 $res = $db->select( array( 'page', $table ),
1618                         array( 'page_namespace', 'page_title', 'page_id' ),
1619                         array(
1620                                 "{$prefix}_from=page_id",
1621                                 "{$prefix}_namespace" => $this->getNamespace(),
1622                                 "{$prefix}_title"     => $this->getDbKey() ),
1623                         'Title::getLinksTo',
1624                         $options );
1625
1626                 $retVal = array();
1627                 if ( $db->numRows( $res ) ) {
1628                         while ( $row = $db->fetchObject( $res ) ) {
1629                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
1630                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj );
1631                                         $retVal[] = $titleObj;
1632                                 }
1633                         }
1634                 }
1635                 $db->freeResult( $res );
1636                 return $retVal;
1637         }
1638
1639         /**
1640          * Get an array of Title objects using this Title as a template
1641          * Also stores the IDs in the link cache.
1642          *
1643          * WARNING: do not use this function on arbitrary user-supplied titles!
1644          * On heavily-used templates it will max out the memory.
1645          *
1646          * @param string $options may be FOR UPDATE
1647          * @return array the Title objects linking here
1648          * @access public
1649          */
1650         function getTemplateLinksTo( $options = '' ) {
1651                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
1652         }
1653
1654         /**
1655          * Get an array of Title objects referring to non-existent articles linked from this page
1656          *
1657          * @param string $options may be FOR UPDATE
1658          * @return array the Title objects
1659          * @access public
1660          */
1661         function getBrokenLinksFrom( $options = '' ) {
1662                 if ( $options ) {
1663                         $db =& wfGetDB( DB_MASTER );
1664                 } else {
1665                         $db =& wfGetDB( DB_SLAVE );
1666                 }
1667
1668                 $res = $db->safeQuery(
1669                           "SELECT pl_namespace, pl_title
1670                              FROM !
1671                         LEFT JOIN !
1672                                ON pl_namespace=page_namespace
1673                               AND pl_title=page_title
1674                             WHERE pl_from=?
1675                               AND page_namespace IS NULL
1676                                   !",
1677                         $db->tableName( 'pagelinks' ),
1678                         $db->tableName( 'page' ),
1679                         $this->getArticleId(),
1680                         $options );
1681
1682                 $retVal = array();
1683                 if ( $db->numRows( $res ) ) {
1684                         while ( $row = $db->fetchObject( $res ) ) {
1685                                 $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
1686                         }
1687                 }
1688                 $db->freeResult( $res );
1689                 return $retVal;
1690         }
1691
1692
1693         /**
1694          * Get a list of URLs to purge from the Squid cache when this
1695          * page changes
1696          *
1697          * @return array the URLs
1698          * @access public
1699          */
1700         function getSquidURLs() {
1701                 return array(
1702                         $this->getInternalURL(),
1703                         $this->getInternalURL( 'action=history' )
1704                 );
1705         }
1706
1707         function purgeSquid() {
1708                 global $wgUseSquid;
1709                 if ( $wgUseSquid ) {
1710                         $urls = $this->getSquidURLs();
1711                         $u = new SquidUpdate( $urls );
1712                         $u->doUpdate();
1713                 }
1714         }
1715
1716         /**
1717          * Move this page without authentication
1718          * @param Title &$nt the new page Title
1719          * @access public
1720          */
1721         function moveNoAuth( &$nt ) {
1722                 return $this->moveTo( $nt, false );
1723         }
1724
1725         /**
1726          * Check whether a given move operation would be valid.
1727          * Returns true if ok, or a message key string for an error message
1728          * if invalid. (Scarrrrry ugly interface this.)
1729          * @param Title &$nt the new title
1730          * @param bool $auth indicates whether $wgUser's permissions
1731          *      should be checked
1732          * @return mixed true on success, message name on failure
1733          * @access public
1734          */
1735         function isValidMoveOperation( &$nt, $auth = true ) {
1736                 if( !$this or !$nt ) {
1737                         return 'badtitletext';
1738                 }
1739                 if( $this->equals( $nt ) ) {
1740                         return 'selfmove';
1741                 }
1742                 if( !$this->isMovable() || !$nt->isMovable() ) {
1743                         return 'immobile_namespace';
1744                 }
1745
1746                 $oldid = $this->getArticleID();
1747                 $newid = $nt->getArticleID();
1748
1749                 if ( strlen( $nt->getDBkey() ) < 1 ) {
1750                         return 'articleexists';
1751                 }
1752                 if ( ( '' == $this->getDBkey() ) ||
1753                          ( !$oldid ) ||
1754                      ( '' == $nt->getDBkey() ) ) {
1755                         return 'badarticleerror';
1756                 }
1757
1758                 if ( $auth && (
1759                                 !$this->userCanEdit() || !$nt->userCanEdit() ||
1760                                 !$this->userCanMove() || !$nt->userCanMove() ) ) {
1761                         return 'protectedpage';
1762                 }
1763
1764                 # The move is allowed only if (1) the target doesn't exist, or
1765                 # (2) the target is a redirect to the source, and has no history
1766                 # (so we can undo bad moves right after they're done).
1767
1768                 if ( 0 != $newid ) { # Target exists; check for validity
1769                         if ( ! $this->isValidMoveTarget( $nt ) ) {
1770                                 return 'articleexists';
1771                         }
1772                 }
1773                 return true;
1774         }
1775
1776         /**
1777          * Move a title to a new location
1778          * @param Title &$nt the new title
1779          * @param bool $auth indicates whether $wgUser's permissions
1780          *      should be checked
1781          * @return mixed true on success, message name on failure
1782          * @access public
1783          */
1784         function moveTo( &$nt, $auth = true, $reason = '' ) {
1785                 $err = $this->isValidMoveOperation( $nt, $auth );
1786                 if( is_string( $err ) ) {
1787                         return $err;
1788                 }
1789
1790                 $pageid = $this->getArticleID();
1791                 if( $nt->exists() ) {
1792                         $this->moveOverExistingRedirect( $nt, $reason );
1793                         $pageCountChange = 0;
1794                 } else { # Target didn't exist, do normal move.
1795                         $this->moveToNewTitle( $nt, $reason );
1796                         $pageCountChange = 1;
1797                 }
1798                 $redirid = $this->getArticleID();
1799
1800                 # Fixing category links (those without piped 'alternate' names) to be sorted under the new title
1801                 $dbw =& wfGetDB( DB_MASTER );
1802                 $categorylinks = $dbw->tableName( 'categorylinks' );
1803                 $sql = "UPDATE $categorylinks SET cl_sortkey=" . $dbw->addQuotes( $nt->getPrefixedText() ) .
1804                         " WHERE cl_from=" . $dbw->addQuotes( $pageid ) .
1805                         " AND cl_sortkey=" . $dbw->addQuotes( $this->getPrefixedText() );
1806                 $dbw->query( $sql, 'SpecialMovepage::doSubmit' );
1807
1808                 # Update watchlists
1809
1810                 $oldnamespace = $this->getNamespace() & ~1;
1811                 $newnamespace = $nt->getNamespace() & ~1;
1812                 $oldtitle = $this->getDBkey();
1813                 $newtitle = $nt->getDBkey();
1814
1815                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
1816                         WatchedItem::duplicateEntries( $this, $nt );
1817                 }
1818
1819                 # Update search engine
1820                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
1821                 $u->doUpdate();
1822                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
1823                 $u->doUpdate();
1824
1825                 # Update site_stats
1826                 if ( $this->getNamespace() == NS_MAIN and $nt->getNamespace() != NS_MAIN ) {
1827                         # Moved out of main namespace
1828                         # not viewed, edited, removing
1829                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange);
1830                 } elseif ( $this->getNamespace() != NS_MAIN and $nt->getNamespace() == NS_MAIN ) {
1831                         # Moved into main namespace
1832                         # not viewed, edited, adding
1833                         $u = new SiteStatsUpdate( 0, 1, +1, $pageCountChange );
1834                 } elseif ( $pageCountChange ) {
1835                         # Added redirect
1836                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
1837                 } else{
1838                         $u = false;
1839                 }
1840                 if ( $u ) {
1841                         $u->doUpdate();
1842                 }
1843
1844                 global $wgUser;
1845                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
1846                 return true;
1847         }
1848
1849         /**
1850          * Move page to a title which is at present a redirect to the
1851          * source page
1852          *
1853          * @param Title &$nt the page to move to, which should currently
1854          *      be a redirect
1855          * @private
1856          */
1857         function moveOverExistingRedirect( &$nt, $reason = '' ) {
1858                 global $wgUseSquid;
1859                 $fname = 'Title::moveOverExistingRedirect';
1860                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
1861
1862                 if ( $reason ) {
1863                         $comment .= ": $reason";
1864                 }
1865
1866                 $now = wfTimestampNow();
1867                 $rand = wfRandom();
1868                 $newid = $nt->getArticleID();
1869                 $oldid = $this->getArticleID();
1870                 $dbw =& wfGetDB( DB_MASTER );
1871                 $linkCache =& LinkCache::singleton();
1872
1873                 # Delete the old redirect. We don't save it to history since
1874                 # by definition if we've got here it's rather uninteresting.
1875                 # We have to remove it so that the next step doesn't trigger
1876                 # a conflict on the unique namespace+title index...
1877                 $dbw->delete( 'page', array( 'page_id' => $newid ), $fname );
1878
1879                 # Save a null revision in the page's history notifying of the move
1880                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
1881                 $nullRevId = $nullRevision->insertOn( $dbw );
1882
1883                 # Change the name of the target page:
1884                 $dbw->update( 'page',
1885                         /* SET */ array(
1886                                 'page_touched'   => $dbw->timestamp($now),
1887                                 'page_namespace' => $nt->getNamespace(),
1888                                 'page_title'     => $nt->getDBkey(),
1889                                 'page_latest'    => $nullRevId,
1890                         ),
1891                         /* WHERE */ array( 'page_id' => $oldid ),
1892                         $fname
1893                 );
1894                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
1895
1896                 # Recreate the redirect, this time in the other direction.
1897                 $mwRedir = MagicWord::get( 'redirect' );
1898                 $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
1899                 $redirectArticle = new Article( $this );
1900                 $newid = $redirectArticle->insertOn( $dbw );
1901                 $redirectRevision = new Revision( array(
1902                         'page'    => $newid,
1903                         'comment' => $comment,
1904                         'text'    => $redirectText ) );
1905                 $revid = $redirectRevision->insertOn( $dbw );
1906                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
1907                 $linkCache->clearLink( $this->getPrefixedDBkey() );
1908
1909                 # Log the move
1910                 $log = new LogPage( 'move' );
1911                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText() ) );
1912
1913                 # Now, we record the link from the redirect to the new title.
1914                 # It should have no other outgoing links...
1915                 $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), $fname );
1916                 $dbw->insert( 'pagelinks',
1917                         array(
1918                                 'pl_from'      => $newid,
1919                                 'pl_namespace' => $nt->getNamespace(),
1920                                 'pl_title'     => $nt->getDbKey() ),
1921                         $fname );
1922
1923                 # Purge squid
1924                 if ( $wgUseSquid ) {
1925                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
1926                         $u = new SquidUpdate( $urls );
1927                         $u->doUpdate();
1928                 }
1929         }
1930
1931         /**
1932          * Move page to non-existing title.
1933          * @param Title &$nt the new Title
1934          * @private
1935          */
1936         function moveToNewTitle( &$nt, $reason = '' ) {
1937                 global $wgUseSquid;
1938                 $fname = 'MovePageForm::moveToNewTitle';
1939                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
1940                 if ( $reason ) {
1941                         $comment .= ": $reason";
1942                 }
1943
1944                 $newid = $nt->getArticleID();
1945                 $oldid = $this->getArticleID();
1946                 $dbw =& wfGetDB( DB_MASTER );
1947                 $now = $dbw->timestamp();
1948                 $rand = wfRandom();
1949                 $linkCache =& LinkCache::singleton();
1950
1951                 # Save a null revision in the page's history notifying of the move
1952                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
1953                 $nullRevId = $nullRevision->insertOn( $dbw );
1954
1955                 # Rename cur entry
1956                 $dbw->update( 'page',
1957                         /* SET */ array(
1958                                 'page_touched'   => $now,
1959                                 'page_namespace' => $nt->getNamespace(),
1960                                 'page_title'     => $nt->getDBkey(),
1961                                 'page_latest'    => $nullRevId,
1962                         ),
1963                         /* WHERE */ array( 'page_id' => $oldid ),
1964                         $fname
1965                 );
1966
1967                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
1968
1969                 # Insert redirect
1970                 $mwRedir = MagicWord::get( 'redirect' );
1971                 $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
1972                 $redirectArticle = new Article( $this );
1973                 $newid = $redirectArticle->insertOn( $dbw );
1974                 $redirectRevision = new Revision( array(
1975                         'page'    => $newid,
1976                         'comment' => $comment,
1977                         'text'    => $redirectText ) );
1978                 $revid = $redirectRevision->insertOn( $dbw );
1979                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
1980                 $linkCache->clearLink( $this->getPrefixedDBkey() );
1981
1982                 # Log the move
1983                 $log = new LogPage( 'move' );
1984                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText()) );
1985
1986                 # Purge caches as per article creation
1987                 Article::onArticleCreate( $nt );
1988
1989                 # Record the just-created redirect's linking to the page
1990                 $dbw->insert( 'pagelinks',
1991                         array(
1992                                 'pl_from'      => $newid,
1993                                 'pl_namespace' => $nt->getNamespace(),
1994                                 'pl_title'     => $nt->getDBkey() ),
1995                         $fname );
1996
1997                 # Purge old title from squid
1998                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
1999                 $this->purgeSquid();
2000         }
2001
2002         /**
2003          * Checks if $this can be moved to a given Title
2004          * - Selects for update, so don't call it unless you mean business
2005          *
2006          * @param Title &$nt the new title to check
2007          * @access public
2008          */
2009         function isValidMoveTarget( $nt ) {
2010
2011                 $fname = 'Title::isValidMoveTarget';
2012                 $dbw =& wfGetDB( DB_MASTER );
2013
2014                 # Is it a redirect?
2015                 $id  = $nt->getArticleID();
2016                 $obj = $dbw->selectRow( array( 'page', 'revision', 'text'),
2017                         array( 'page_is_redirect','old_text','old_flags' ),
2018                         array( 'page_id' => $id, 'page_latest=rev_id', 'rev_text_id=old_id' ),
2019                         $fname, 'FOR UPDATE' );
2020
2021                 if ( !$obj || 0 == $obj->page_is_redirect ) {
2022                         # Not a redirect
2023                         wfDebug( __METHOD__ . ": not a redirect\n" );
2024                         return false;
2025                 }
2026                 $text = Revision::getRevisionText( $obj );
2027
2028                 # Does the redirect point to the source?
2029                 # Or is it a broken self-redirect, usually caused by namespace collisions?
2030                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
2031                         $redirTitle = Title::newFromText( $m[1] );
2032                         if( !is_object( $redirTitle ) ||
2033                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
2034                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
2035                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
2036                                 return false;
2037                         }
2038                 } else {
2039                         # Fail safe
2040                         wfDebug( __METHOD__ . ": failsafe\n" );
2041                         return false;
2042                 }
2043
2044                 # Does the article have a history?
2045                 $row = $dbw->selectRow( array( 'page', 'revision'),
2046                         array( 'rev_id' ),
2047                         array( 'page_namespace' => $nt->getNamespace(),
2048                                 'page_title' => $nt->getDBkey(),
2049                                 'page_id=rev_page AND page_latest != rev_id'
2050                         ), $fname, 'FOR UPDATE'
2051                 );
2052
2053                 # Return true if there was no history
2054                 return $row === false;
2055         }
2056
2057         /**
2058          * Create a redirect; fails if the title already exists; does
2059          * not notify RC
2060          *
2061          * @param Title $dest the destination of the redirect
2062          * @param string $comment the comment string describing the move
2063          * @return bool true on success
2064          * @access public
2065          */
2066         function createRedirect( $dest, $comment ) {
2067                 if ( $this->getArticleID() ) {
2068                         return false;
2069                 }
2070
2071                 $fname = 'Title::createRedirect';
2072                 $dbw =& wfGetDB( DB_MASTER );
2073
2074                 $article = new Article( $this );
2075                 $newid = $article->insertOn( $dbw );
2076                 $revision = new Revision( array(
2077                         'page'      => $newid,
2078                         'comment'   => $comment,
2079                         'text'      => "#REDIRECT [[" . $dest->getPrefixedText() . "]]\n",
2080                         ) );
2081                 $revisionId = $revision->insertOn( $dbw );
2082                 $article->updateRevisionOn( $dbw, $revision, 0 );
2083
2084                 # Link table
2085                 $dbw->insert( 'pagelinks',
2086                         array(
2087                                 'pl_from'      => $newid,
2088                                 'pl_namespace' => $dest->getNamespace(),
2089                                 'pl_title'     => $dest->getDbKey()
2090                         ), $fname
2091                 );
2092
2093                 Article::onArticleCreate( $this );
2094                 return true;
2095         }
2096
2097         /**
2098          * Get categories to which this Title belongs and return an array of
2099          * categories' names.
2100          *
2101          * @return array an array of parents in the form:
2102          *      $parent => $currentarticle
2103          * @access public
2104          */
2105         function getParentCategories() {
2106                 global $wgContLang;
2107
2108                 $titlekey = $this->getArticleId();
2109                 $dbr =& wfGetDB( DB_SLAVE );
2110                 $categorylinks = $dbr->tableName( 'categorylinks' );
2111
2112                 # NEW SQL
2113                 $sql = "SELECT * FROM $categorylinks"
2114                      ." WHERE cl_from='$titlekey'"
2115                          ." AND cl_from <> '0'"
2116                          ." ORDER BY cl_sortkey";
2117
2118                 $res = $dbr->query ( $sql ) ;
2119
2120                 if($dbr->numRows($res) > 0) {
2121                         while ( $x = $dbr->fetchObject ( $res ) )
2122                                 //$data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to);
2123                                 $data[$wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to] = $this->getFullText();
2124                         $dbr->freeResult ( $res ) ;
2125                 } else {
2126                         $data = '';
2127                 }
2128                 return $data;
2129         }
2130
2131         /**
2132          * Get a tree of parent categories
2133          * @param array $children an array with the children in the keys, to check for circular refs
2134          * @return array
2135          * @access public
2136          */
2137         function getParentCategoryTree( $children = array() ) {
2138                 $parents = $this->getParentCategories();
2139
2140                 if($parents != '') {
2141                         foreach($parents as $parent => $current) {
2142                                 if ( array_key_exists( $parent, $children ) ) {
2143                                         # Circular reference
2144                                         $stack[$parent] = array();
2145                                 } else {
2146                                         $nt = Title::newFromText($parent);
2147                                         if ( $nt ) {
2148                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array($parent => 1) );
2149                                         }
2150                                 }
2151                         }
2152                         return $stack;
2153                 } else {
2154                         return array();
2155                 }
2156         }
2157
2158
2159         /**
2160          * Get an associative array for selecting this title from
2161          * the "page" table
2162          *
2163          * @return array
2164          * @access public
2165          */
2166         function pageCond() {
2167                 return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
2168         }
2169
2170         /**
2171          * Get the revision ID of the previous revision
2172          *
2173          * @param integer $revision  Revision ID. Get the revision that was before this one.
2174          * @return interger $oldrevision|false
2175          */
2176         function getPreviousRevisionID( $revision ) {
2177                 $dbr =& wfGetDB( DB_SLAVE );
2178                 return $dbr->selectField( 'revision', 'rev_id',
2179                         'rev_page=' . intval( $this->getArticleId() ) .
2180                         ' AND rev_id<' . intval( $revision ) . ' ORDER BY rev_id DESC' );
2181         }
2182
2183         /**
2184          * Get the revision ID of the next revision
2185          *
2186          * @param integer $revision  Revision ID. Get the revision that was after this one.
2187          * @return interger $oldrevision|false
2188          */
2189         function getNextRevisionID( $revision ) {
2190                 $dbr =& wfGetDB( DB_SLAVE );
2191                 return $dbr->selectField( 'revision', 'rev_id',
2192                         'rev_page=' . intval( $this->getArticleId() ) .
2193                         ' AND rev_id>' . intval( $revision ) . ' ORDER BY rev_id' );
2194         }
2195
2196         /**
2197          * Compare with another title.
2198          *
2199          * @param Title $title
2200          * @return bool
2201          */
2202         function equals( $title ) {
2203                 // Note: === is necessary for proper matching of number-like titles.
2204                 return $this->getInterwiki() === $title->getInterwiki()
2205                         && $this->getNamespace() == $title->getNamespace()
2206                         && $this->getDbkey() === $title->getDbkey();
2207         }
2208
2209         /**
2210          * Check if page exists
2211          * @return bool
2212          */
2213         function exists() {
2214                 return $this->getArticleId() != 0;
2215         }
2216
2217         /**
2218          * Should a link should be displayed as a known link, just based on its title?
2219          *
2220          * Currently, a self-link with a fragment and special pages are in
2221          * this category. Special pages never exist in the database.
2222          */
2223         function isAlwaysKnown() {
2224                 return  $this->isExternal() || ( 0 == $this->mNamespace && "" == $this->mDbkeyform )
2225                   || NS_SPECIAL == $this->mNamespace;
2226         }
2227
2228         /**
2229          * Update page_touched timestamps and send squid purge messages for
2230          * pages linking to this title. May be sent to the job queue depending
2231          * on the number of links. Typically called on create and delete.
2232          */
2233         function touchLinks() {
2234                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
2235                 $u->doUpdate();
2236
2237                 if ( $this->getNamespace() == NS_CATEGORY ) {
2238                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
2239                         $u->doUpdate();
2240                 }
2241         }
2242
2243         /**
2244          * Get the last touched timestamp
2245          */
2246         function getTouched() {
2247                 $dbr =& wfGetDB( DB_SLAVE );
2248                 $touched = $dbr->selectField( 'page', 'page_touched',
2249                         array(
2250                                 'page_namespace' => $this->getNamespace(),
2251                                 'page_title' => $this->getDBkey()
2252                         ), __METHOD__
2253                 );
2254                 return $touched;
2255         }
2256
2257         /**
2258          * Get a cached value from a global cache that is invalidated when this page changes
2259          * @param string $key the key
2260          * @param callback $callback A callback function which generates the value on cache miss
2261          */
2262         function getRelatedCache( $memc, $key, $expiry, $callback, $params = array() ) {
2263                 $touched = $this->getTouched();
2264                 $cacheEntry = $memc->get( $key );
2265                 if ( $cacheEntry ) {
2266                         if ( $cacheEntry['touched'] >= $touched ) {
2267                                 return $cacheEntry['value'];
2268                         } else {
2269                                 wfDebug( __METHOD__.": $key expired\n" );
2270                         }
2271                 } else {
2272                         wfDebug( __METHOD__.": $key not found\n" );
2273                 }
2274                 $value = call_user_func_array( $callback, $params );
2275                 $cacheEntry = array(
2276                         'value' => $value,
2277                         'touched' => $touched
2278                 );
2279                 $memc->set( $key, $cacheEntry, $expiry );
2280                 return $value;
2281         }
2282
2283         function trackbackURL() {
2284                 global $wgTitle, $wgScriptPath, $wgServer;
2285
2286                 return "$wgServer$wgScriptPath/trackback.php?article="
2287                         . htmlspecialchars(urlencode($wgTitle->getPrefixedDBkey()));
2288         }
2289
2290         function trackbackRDF() {
2291                 $url = htmlspecialchars($this->getFullURL());
2292                 $title = htmlspecialchars($this->getText());
2293                 $tburl = $this->trackbackURL();
2294
2295                 return "
2296 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
2297          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
2298          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
2299 <rdf:Description
2300    rdf:about=\"$url\"
2301    dc:identifier=\"$url\"
2302    dc:title=\"$title\"
2303    trackback:ping=\"$tburl\" />
2304 </rdf:RDF>";
2305         }
2306
2307         /**
2308          * Generate strings used for xml 'id' names in monobook tabs
2309          * @return string
2310          */
2311         function getNamespaceKey() {
2312                 switch ($this->getNamespace()) {
2313                         case NS_MAIN:
2314                         case NS_TALK:
2315                                 return 'nstab-main';
2316                         case NS_USER:
2317                         case NS_USER_TALK:
2318                                 return 'nstab-user';
2319                         case NS_MEDIA:
2320                                 return 'nstab-media';
2321                         case NS_SPECIAL:
2322                                 return 'nstab-special';
2323                         case NS_PROJECT:
2324                         case NS_PROJECT_TALK:
2325                                 return 'nstab-project';
2326                         case NS_IMAGE:
2327                         case NS_IMAGE_TALK:
2328                                 return 'nstab-image';
2329                         case NS_MEDIAWIKI:
2330                         case NS_MEDIAWIKI_TALK:
2331                                 return 'nstab-mediawiki';
2332                         case NS_TEMPLATE:
2333                         case NS_TEMPLATE_TALK:
2334                                 return 'nstab-template';
2335                         case NS_HELP:
2336                         case NS_HELP_TALK:
2337                                 return 'nstab-help';
2338                         case NS_CATEGORY:
2339                         case NS_CATEGORY_TALK:
2340                                 return 'nstab-category';
2341                         default:
2342                                 return 'nstab-' . strtolower( $this->getSubjectNsText() );
2343                 }
2344         }
2345 }
2346 ?>