includes/Title.php

   1 <?php
   2 /**
   3  * See title.txt
   4  *
   5  */
   6
   7 /** */
   8 if ( !class_exists( 'UtfNormal' ) ) {
   9         require_once( dirname(__FILE__) . '/normal/UtfNormal.php' );
  10 }
  11
  12 define ( 'GAID_FOR_UPDATE', 1 );
  13
  14 # Title::newFromTitle maintains a cache to avoid
  15 # expensive re-normalization of commonly used titles.
  16 # On a batch operation this can become a memory leak
  17 # if not bounded. After hitting this many titles,
  18 # reset the cache.
  19 define( 'MW_TITLECACHE_MAX', 1000 );
  20
  21 # Constants for pr_cascade bitfield
  22 define( 'CASCADE', 1 );
  23
  24 /**
  25  * Title class
  26  * - Represents a title, which may contain an interwiki designation or namespace
  27  * - Can fetch various kinds of data from the database, albeit inefficiently.
  28  *
  29  */
  30 class Title {
  31         /**
  32          * Static cache variables
  33          */
  34         static private $titleCache=array();
  35         static private $interwikiCache=array();
  36
  37
  38         /**
  39          * All member variables should be considered private
  40          * Please use the accessor functions
  41          */
  42
  43         /**#@+
  44          * @private
  45          */
  46
  47         var $mTextform;                 # Text form (spaces not underscores) of the main part
  48         var $mUrlform;                  # URL-encoded form of the main part
  49         var $mDbkeyform;                # Main part with underscores
  50         var $mUserCaseDBKey;        # DB key with the initial letter in the case specified by the user
  51         var $mNamespace;                # Namespace index, i.e. one of the NS_xxxx constants
  52         var $mInterwiki;                # Interwiki prefix (or null string)
  53         var $mFragment;                 # Title fragment (i.e. the bit after the #)
  54         var $mArticleID;                # Article ID, fetched from the link cache on demand
  55         var $mLatestID;                 # ID of most recent revision
  56         var $mRestrictions;             # Array of groups allowed to edit this article
  57         var $mCascadeRestriction;       # Cascade restrictions on this page to included templates and images?
  58         var $mRestrictionsExpiry;       # When do the restrictions on this page expire?
  59         var $mHasCascadingRestrictions; # Are cascading restrictions in effect on this page?
  60         var $mCascadeRestrictionSources;# Where are the cascading restrictions coming from on this page?
  61         var $mRestrictionsLoaded;       # Boolean for initialisation on demand
  62         var $mPrefixedText;             # Text form including namespace/interwiki, initialised on demand
  63         var $mDefaultNamespace;         # Namespace index when there is no namespace
  64                                         # Zero except in {{transclusion}} tags
  65         var $mWatched;                  # Is $wgUser watching this page? NULL if unfilled, accessed through userIsWatching()
  66         /**#@-*/
  67
  68
  69         /**
  70          * Constructor
  71          * @private
  72          */
  73         /* private */ function __construct() {
  74                 $this->mInterwiki = $this->mUrlform =
  75                 $this->mTextform = $this->mDbkeyform = '';
  76                 $this->mArticleID = -1;
  77                 $this->mNamespace = NS_MAIN;
  78                 $this->mRestrictionsLoaded = false;
  79                 $this->mRestrictions = array();
  80                 # Dont change the following, NS_MAIN is hardcoded in several place
  81                 # See bug #696
  82                 $this->mDefaultNamespace = NS_MAIN;
  83                 $this->mWatched = NULL;
  84                 $this->mLatestID = false;
  85                 $this->mOldRestrictions = false;
  86         }
  87
  88         /**
  89          * Create a new Title from a prefixed DB key
  90          * @param string $key The database key, which has underscores
  91          *      instead of spaces, possibly including namespace and
  92          *      interwiki prefixes
  93          * @return Title the new object, or NULL on an error
  94          */
  95         public static function newFromDBkey( $key ) {
  96                 $t = new Title();
  97                 $t->mDbkeyform = $key;
  98                 if( $t->secureAndSplit() )
  99                         return $t;
 100                 else
 101                         return NULL;
 102         }
 103
 104         /**
 105          * Create a new Title from text, such as what one would
 106          * find in a link. Decodes any HTML entities in the text.
 107          *
 108          * @param string $text the link text; spaces, prefixes,
 109          *      and an initial ':' indicating the main namespace
 110          *      are accepted
 111          * @param int $defaultNamespace the namespace to use if
 112          *      none is specified by a prefix
 113          * @return Title the new object, or NULL on an error
 114          */
 115         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 116                 if( is_object( $text ) ) {
 117                         throw new MWException( 'Title::newFromText given an object' );
 118                 }
 119
 120                 /**
 121                  * Wiki pages often contain multiple links to the same page.
 122                  * Title normalization and parsing can become expensive on
 123                  * pages with many links, so we can save a little time by
 124                  * caching them.
 125                  *
 126                  * In theory these are value objects and won't get changed...
 127                  */
 128                 if( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 129                         return Title::$titleCache[$text];
 130                 }
 131
 132                 /**
 133                  * Convert things like &eacute; &#257; or &#x3017; into real text...
 134                  */
 135                 $filteredText = Sanitizer::decodeCharReferences( $text );
 136
 137                 $t = new Title();
 138                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 139                 $t->mDefaultNamespace = $defaultNamespace;
 140
 141                 static $cachedcount = 0 ;
 142                 if( $t->secureAndSplit() ) {
 143                         if( $defaultNamespace == NS_MAIN ) {
 144                                 if( $cachedcount >= MW_TITLECACHE_MAX ) {
 145                                         # Avoid memory leaks on mass operations...
 146                                         Title::$titleCache = array();
 147                                         $cachedcount=0;
 148                                 }
 149                                 $cachedcount++;
 150                                 Title::$titleCache[$text] =& $t;
 151                         }
 152                         return $t;
 153                 } else {
 154                         $ret = NULL;
 155                         return $ret;
 156                 }
 157         }
 158
 159         /**
 160          * Create a new Title from URL-encoded text. Ensures that
 161          * the given title's length does not exceed the maximum.
 162          * @param string $url the title, as might be taken from a URL
 163          * @return Title the new object, or NULL on an error
 164          */
 165         public static function newFromURL( $url ) {
 166                 global $wgLegalTitleChars;
 167                 $t = new Title();
 168
 169                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 170                 # but some URLs used it as a space replacement and they still come
 171                 # from some external search tools.
 172                 if ( strpos( $wgLegalTitleChars, '+' ) === false ) {
 173                         $url = str_replace( '+', ' ', $url );
 174                 }
 175
 176                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 177                 if( $t->secureAndSplit() ) {
 178                         return $t;
 179                 } else {
 180                         return NULL;
 181                 }
 182         }
 183
 184         /**
 185          * Create a new Title from an article ID
 186          *
 187          * @todo This is inefficiently implemented, the page row is requested
 188          *       but not used for anything else
 189          *
 190          * @param int $id the page_id corresponding to the Title to create
 191          * @return Title the new object, or NULL on an error
 192          */
 193         public static function newFromID( $id ) {
 194                 $fname = 'Title::newFromID';
 195                 $dbr = wfGetDB( DB_SLAVE );
 196                 $row = $dbr->selectRow( 'page', array( 'page_namespace', 'page_title' ),
 197                         array( 'page_id' => $id ), $fname );
 198                 if ( $row !== false ) {
 199                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 200                 } else {
 201                         $title = NULL;
 202                 }
 203                 return $title;
 204         }
 205
 206         /**
 207          * Make an array of titles from an array of IDs
 208          */
 209         public static function newFromIDs( $ids ) {
 210                 $dbr = wfGetDB( DB_SLAVE );
 211                 $res = $dbr->select( 'page', array( 'page_namespace', 'page_title' ),
 212                         'page_id IN (' . $dbr->makeList( $ids ) . ')', __METHOD__ );
 213
 214                 $titles = array();
 215                 while ( $row = $dbr->fetchObject( $res ) ) {
 216                         $titles[] = Title::makeTitle( $row->page_namespace, $row->page_title );
 217                 }
 218                 return $titles;
 219         }
 220
 221         /**
 222          * Create a new Title from a namespace index and a DB key.
 223          * It's assumed that $ns and $title are *valid*, for instance when
 224          * they came directly from the database or a special page name.
 225          * For convenience, spaces are converted to underscores so that
 226          * eg user_text fields can be used directly.
 227          *
 228          * @param int $ns the namespace of the article
 229          * @param string $title the unprefixed database key form
 230          * @return Title the new object
 231          */
 232         public static function &makeTitle( $ns, $title ) {
 233                 $t = new Title();
 234                 $t->mInterwiki = '';
 235                 $t->mFragment = '';
 236                 $t->mNamespace = $ns = intval( $ns );
 237                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 238                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 239                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 240                 $t->mTextform = str_replace( '_', ' ', $title );
 241                 return $t;
 242         }
 243
 244         /**
 245          * Create a new Title from a namespace index and a DB key.
 246          * The parameters will be checked for validity, which is a bit slower
 247          * than makeTitle() but safer for user-provided data.
 248          *
 249          * @param int $ns the namespace of the article
 250          * @param string $title the database key form
 251          * @return Title the new object, or NULL on an error
 252          */
 253         public static function makeTitleSafe( $ns, $title ) {
 254                 $t = new Title();
 255                 $t->mDbkeyform = Title::makeName( $ns, $title );
 256                 if( $t->secureAndSplit() ) {
 257                         return $t;
 258                 } else {
 259                         return NULL;
 260                 }
 261         }
 262
 263         /**
 264          * Create a new Title for the Main Page
 265          * @return Title the new object
 266          */
 267         public static function newMainPage() {
 268                 return Title::newFromText( wfMsgForContent( 'mainpage' ) );
 269         }
 270
 271         /**
 272          * Extract a redirect destination from a string and return the
 273          * Title, or null if the text doesn't contain a valid redirect
 274          *
 275          * @param string $text Text with possible redirect
 276          * @return Title
 277          */
 278         public static function newFromRedirect( $text ) {
 279                 $redir = MagicWord::get( 'redirect' );
 280                 if( $redir->matchStart( $text ) ) {
 281                         // Extract the first link and see if it's usable
 282                         $m = array();
 283                         if( preg_match( '!\[{2}(.*?)(?:\||\]{2})!', $text, $m ) ) {
 284                                 // Strip preceding colon used to "escape" categories, etc.
 285                                 // and URL-decode links
 286                                 if( strpos( $m[1], '%' ) !== false ) {
 287                                         // Match behavior of inline link parsing here;
 288                                         // don't interpret + as " " most of the time!
 289                                         // It might be safe to just use rawurldecode instead, though.
 290                                         $m[1] = urldecode( ltrim( $m[1], ':' ) );
 291                                 }
 292                                 $title = Title::newFromText( $m[1] );
 293                                 // Redirects to Special:Userlogout are not permitted
 294                                 if( $title instanceof Title && !$title->isSpecial( 'Userlogout' ) )
 295                                         return $title;
 296                         }
 297                 }
 298                 return null;
 299         }
 300
 301 #----------------------------------------------------------------------------
 302 #       Static functions
 303 #----------------------------------------------------------------------------
 304
 305         /**
 306          * Get the prefixed DB key associated with an ID
 307          * @param int $id the page_id of the article
 308          * @return Title an object representing the article, or NULL
 309          *      if no such article was found
 310          * @static
 311          * @access public
 312          */
 313         function nameOf( $id ) {
 314                 $fname = 'Title::nameOf';
 315                 $dbr = wfGetDB( DB_SLAVE );
 316
 317                 $s = $dbr->selectRow( 'page', array( 'page_namespace','page_title' ),  array( 'page_id' => $id ), $fname );
 318                 if ( $s === false ) { return NULL; }
 319
 320                 $n = Title::makeName( $s->page_namespace, $s->page_title );
 321                 return $n;
 322         }
 323
 324         /**
 325          * Get a regex character class describing the legal characters in a link
 326          * @return string the list of characters, not delimited
 327          */
 328         public static function legalChars() {
 329                 global $wgLegalTitleChars;
 330                 return $wgLegalTitleChars;
 331         }
 332
 333         /**
 334          * Get a string representation of a title suitable for
 335          * including in a search index
 336          *
 337          * @param int $ns a namespace index
 338          * @param string $title text-form main part
 339          * @return string a stripped-down title string ready for the
 340          *      search index
 341          */
 342         public static function indexTitle( $ns, $title ) {
 343                 global $wgContLang;
 344
 345                 $lc = SearchEngine::legalSearchChars() . '&#;';
 346                 $t = $wgContLang->stripForSearch( $title );
 347                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 348                 $t = $wgContLang->lc( $t );
 349
 350                 # Handle 's, s'
 351                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 352                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 353
 354                 $t = preg_replace( "/\\s+/", ' ', $t );
 355
 356                 if ( $ns == NS_IMAGE ) {
 357                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 358                 }
 359                 return trim( $t );
 360         }
 361
 362         /*
 363          * Make a prefixed DB key from a DB key and a namespace index
 364          * @param int $ns numerical representation of the namespace
 365          * @param string $title the DB key form the title
 366          * @return string the prefixed form of the title
 367          */
 368         public static function makeName( $ns, $title ) {
 369                 global $wgContLang;
 370
 371                 $n = $wgContLang->getNsText( $ns );
 372                 return $n == '' ? $title : "$n:$title";
 373         }
 374
 375         /**
 376          * Returns the URL associated with an interwiki prefix
 377          * @param string $key the interwiki prefix (e.g. "MeatBall")
 378          * @return the associated URL, containing "$1", which should be
 379          *      replaced by an article title
 380          * @static (arguably)
 381          */
 382         public function getInterwikiLink( $key )  {
 383                 global $wgMemc, $wgInterwikiExpiry;
 384                 global $wgInterwikiCache, $wgContLang;
 385                 $fname = 'Title::getInterwikiLink';
 386
 387                 $key = $wgContLang->lc( $key );
 388
 389                 $k = wfMemcKey( 'interwiki', $key );
 390                 if( array_key_exists( $k, Title::$interwikiCache ) ) {
 391                         return Title::$interwikiCache[$k]->iw_url;
 392                 }
 393
 394                 if ($wgInterwikiCache) {
 395                         return Title::getInterwikiCached( $key );
 396                 }
 397
 398                 $s = $wgMemc->get( $k );
 399                 # Ignore old keys with no iw_local
 400                 if( $s && isset( $s->iw_local ) && isset($s->iw_trans)) {
 401                         Title::$interwikiCache[$k] = $s;
 402                         return $s->iw_url;
 403                 }
 404
 405                 $dbr = wfGetDB( DB_SLAVE );
 406                 $res = $dbr->select( 'interwiki',
 407                         array( 'iw_url', 'iw_local', 'iw_trans' ),
 408                         array( 'iw_prefix' => $key ), $fname );
 409                 if( !$res ) {
 410                         return '';
 411                 }
 412
 413                 $s = $dbr->fetchObject( $res );
 414                 if( !$s ) {
 415                         # Cache non-existence: create a blank object and save it to memcached
 416                         $s = (object)false;
 417                         $s->iw_url = '';
 418                         $s->iw_local = 0;
 419                         $s->iw_trans = 0;
 420                 }
 421                 $wgMemc->set( $k, $s, $wgInterwikiExpiry );
 422                 Title::$interwikiCache[$k] = $s;
 423
 424                 return $s->iw_url;
 425         }
 426
 427         /**
 428          * Fetch interwiki prefix data from local cache in constant database
 429          *
 430          * More logic is explained in DefaultSettings
 431          *
 432          * @return string URL of interwiki site
 433          */
 434         public static function getInterwikiCached( $key ) {
 435                 global $wgInterwikiCache, $wgInterwikiScopes, $wgInterwikiFallbackSite;
 436                 static $db, $site;
 437
 438                 if (!$db)
 439                         $db=dba_open($wgInterwikiCache,'r','cdb');
 440                 /* Resolve site name */
 441                 if ($wgInterwikiScopes>=3 and !$site) {
 442                         $site = dba_fetch('__sites:' . wfWikiID(), $db);
 443                         if ($site=="")
 444                                 $site = $wgInterwikiFallbackSite;
 445                 }
 446                 $value = dba_fetch( wfMemcKey( $key ), $db);
 447                 if ($value=='' and $wgInterwikiScopes>=3) {
 448                         /* try site-level */
 449                         $value = dba_fetch("_{$site}:{$key}", $db);
 450                 }
 451                 if ($value=='' and $wgInterwikiScopes>=2) {
 452                         /* try globals */
 453                         $value = dba_fetch("__global:{$key}", $db);
 454                 }
 455                 if ($value=='undef')
 456                         $value='';
 457                 $s = (object)false;
 458                 $s->iw_url = '';
 459                 $s->iw_local = 0;
 460                 $s->iw_trans = 0;
 461                 if ($value!='') {
 462                         list($local,$url)=explode(' ',$value,2);
 463                         $s->iw_url=$url;
 464                         $s->iw_local=(int)$local;
 465                 }
 466                 Title::$interwikiCache[wfMemcKey( 'interwiki', $key )] = $s;
 467                 return $s->iw_url;
 468         }
 469         /**
 470          * Determine whether the object refers to a page within
 471          * this project.
 472          *
 473          * @return bool TRUE if this is an in-project interwiki link
 474          *      or a wikilink, FALSE otherwise
 475          */
 476         public function isLocal() {
 477                 if ( $this->mInterwiki != '' ) {
 478                         # Make sure key is loaded into cache
 479                         $this->getInterwikiLink( $this->mInterwiki );
 480                         $k = wfMemcKey( 'interwiki', $this->mInterwiki );
 481                         return (bool)(Title::$interwikiCache[$k]->iw_local);
 482                 } else {
 483                         return true;
 484                 }
 485         }
 486
 487         /**
 488          * Determine whether the object refers to a page within
 489          * this project and is transcludable.
 490          *
 491          * @return bool TRUE if this is transcludable
 492          */
 493         public function isTrans() {
 494                 if ($this->mInterwiki == '')
 495                         return false;
 496                 # Make sure key is loaded into cache
 497                 $this->getInterwikiLink( $this->mInterwiki );
 498                 $k = wfMemcKey( 'interwiki', $this->mInterwiki );
 499                 return (bool)(Title::$interwikiCache[$k]->iw_trans);
 500         }
 501
 502         /**
 503          * Escape a text fragment, say from a link, for a URL
 504          */
 505         static function escapeFragmentForURL( $fragment ) {
 506                 $fragment = str_replace( ' ', '_', $fragment );
 507                 $fragment = urlencode( Sanitizer::decodeCharReferences( $fragment ) );
 508                 $replaceArray = array(
 509                         '%3A' => ':',
 510                         '%' => '.'
 511                 );
 512                 return strtr( $fragment, $replaceArray );
 513         }
 514
 515 #----------------------------------------------------------------------------
 516 #       Other stuff
 517 #----------------------------------------------------------------------------
 518
 519         /** Simple accessors */
 520         /**
 521          * Get the text form (spaces not underscores) of the main part
 522          * @return string
 523          */
 524         public function getText() { return $this->mTextform; }
 525         /**
 526          * Get the URL-encoded form of the main part
 527          * @return string
 528          */
 529         public function getPartialURL() { return $this->mUrlform; }
 530         /**
 531          * Get the main part with underscores
 532          * @return string
 533          */
 534         public function getDBkey() { return $this->mDbkeyform; }
 535         /**
 536          * Get the namespace index, i.e. one of the NS_xxxx constants
 537          * @return int
 538          */
 539         public function getNamespace() { return $this->mNamespace; }
 540         /**
 541          * Get the namespace text
 542          * @return string
 543          */
 544         public function getNsText() {
 545                 global $wgContLang, $wgCanonicalNamespaceNames;
 546
 547                 if ( '' != $this->mInterwiki ) {
 548                         // This probably shouldn't even happen. ohh man, oh yuck.
 549                         // But for interwiki transclusion it sometimes does.
 550                         // Shit. Shit shit shit.
 551                         //
 552                         // Use the canonical namespaces if possible to try to
 553                         // resolve a foreign namespace.
 554                         if( isset( $wgCanonicalNamespaceNames[$this->mNamespace] ) ) {
 555                                 return $wgCanonicalNamespaceNames[$this->mNamespace];
 556                         }
 557                 }
 558                 return $wgContLang->getNsText( $this->mNamespace );
 559         }
 560         /**
 561          * Get the DB key with the initial letter case as specified by the user
 562          */
 563         function getUserCaseDBKey() {
 564                 return $this->mUserCaseDBKey;
 565         }
 566         /**
 567          * Get the namespace text of the subject (rather than talk) page
 568          * @return string
 569          */
 570         public function getSubjectNsText() {
 571                 global $wgContLang;
 572                 return $wgContLang->getNsText( Namespace::getSubject( $this->mNamespace ) );
 573         }
 574
 575         /**
 576          * Get the namespace text of the talk page
 577          * @return string
 578          */
 579         public function getTalkNsText() {
 580                 global $wgContLang;
 581                 return( $wgContLang->getNsText( Namespace::getTalk( $this->mNamespace ) ) );
 582         }
 583
 584         /**
 585          * Could this title have a corresponding talk page?
 586          * @return bool
 587          */
 588         public function canTalk() {
 589                 return( Namespace::canTalk( $this->mNamespace ) );
 590         }
 591
 592         /**
 593          * Get the interwiki prefix (or null string)
 594          * @return string
 595          */
 596         public function getInterwiki() { return $this->mInterwiki; }
 597         /**
 598          * Get the Title fragment (i.e. the bit after the #) in text form
 599          * @return string
 600          */
 601         public function getFragment() { return $this->mFragment; }
 602         /**
 603          * Get the fragment in URL form, including the "#" character if there is one
 604          * @return string
 605          */
 606         public function getFragmentForURL() {
 607                 if ( $this->mFragment == '' ) {
 608                         return '';
 609                 } else {
 610                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
 611                 }
 612         }
 613         /**
 614          * Get the default namespace index, for when there is no namespace
 615          * @return int
 616          */
 617         public function getDefaultNamespace() { return $this->mDefaultNamespace; }
 618
 619         /**
 620          * Get title for search index
 621          * @return string a stripped-down title string ready for the
 622          *      search index
 623          */
 624         public function getIndexTitle() {
 625                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 626         }
 627
 628         /**
 629          * Get the prefixed database key form
 630          * @return string the prefixed title, with underscores and
 631          *      any interwiki and namespace prefixes
 632          */
 633         public function getPrefixedDBkey() {
 634                 $s = $this->prefix( $this->mDbkeyform );
 635                 $s = str_replace( ' ', '_', $s );
 636                 return $s;
 637         }
 638
 639         /**
 640          * Get the prefixed title with spaces.
 641          * This is the form usually used for display
 642          * @return string the prefixed title, with spaces
 643          */
 644         public function getPrefixedText() {
 645                 if ( empty( $this->mPrefixedText ) ) { // FIXME: bad usage of empty() ?
 646                         $s = $this->prefix( $this->mTextform );
 647                         $s = str_replace( '_', ' ', $s );
 648                         $this->mPrefixedText = $s;
 649                 }
 650                 return $this->mPrefixedText;
 651         }
 652
 653         /**
 654          * Get the prefixed title with spaces, plus any fragment
 655          * (part beginning with '#')
 656          * @return string the prefixed title, with spaces and
 657          *      the fragment, including '#'
 658          */
 659         public function getFullText() {
 660                 $text = $this->getPrefixedText();
 661                 if( '' != $this->mFragment ) {
 662                         $text .= '#' . $this->mFragment;
 663                 }
 664                 return $text;
 665         }
 666
 667         /**
 668          * Get the base name, i.e. the leftmost parts before the /
 669          * @return string Base name
 670          */
 671         public function getBaseText() {
 672                 global $wgNamespacesWithSubpages;
 673                 if( isset( $wgNamespacesWithSubpages[ $this->mNamespace ] ) && $wgNamespacesWithSubpages[ $this->mNamespace ] ) {
 674                         $parts = explode( '/', $this->getText() );
 675                         # Don't discard the real title if there's no subpage involved
 676                         if( count( $parts ) > 1 )
 677                                 unset( $parts[ count( $parts ) - 1 ] );
 678                         return implode( '/', $parts );
 679                 } else {
 680                         return $this->getText();
 681                 }
 682         }
 683
 684         /**
 685          * Get the lowest-level subpage name, i.e. the rightmost part after /
 686          * @return string Subpage name
 687          */
 688         public function getSubpageText() {
 689                 global $wgNamespacesWithSubpages;
 690                 if( isset( $wgNamespacesWithSubpages[ $this->mNamespace ] ) && $wgNamespacesWithSubpages[ $this->mNamespace ] ) {
 691                         $parts = explode( '/', $this->mTextform );
 692                         return( $parts[ count( $parts ) - 1 ] );
 693                 } else {
 694                         return( $this->mTextform );
 695                 }
 696         }
 697
 698         /**
 699          * Get a URL-encoded form of the subpage text
 700          * @return string URL-encoded subpage name
 701          */
 702         public function getSubpageUrlForm() {
 703                 $text = $this->getSubpageText();
 704                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
 705                 $text = str_replace( '%28', '(', str_replace( '%29', ')', $text ) ); # Clean up the URL; per below, this might not be safe
 706                 return( $text );
 707         }
 708
 709         /**
 710          * Get a URL-encoded title (not an actual URL) including interwiki
 711          * @return string the URL-encoded form
 712          */
 713         public function getPrefixedURL() {
 714                 $s = $this->prefix( $this->mDbkeyform );
 715                 $s = str_replace( ' ', '_', $s );
 716
 717                 $s = wfUrlencode ( $s ) ;
 718
 719                 # Cleaning up URL to make it look nice -- is this safe?
 720                 $s = str_replace( '%28', '(', $s );
 721                 $s = str_replace( '%29', ')', $s );
 722
 723                 return $s;
 724         }
 725
 726         /**
 727          * Get a real URL referring to this title, with interwiki link and
 728          * fragment
 729          *
 730          * @param string $query an optional query string, not used
 731          *      for interwiki links
 732          * @param string $variant language variant of url (for sr, zh..)
 733          * @return string the URL
 734          */
 735         public function getFullURL( $query = '', $variant = false ) {
 736                 global $wgContLang, $wgServer, $wgRequest;
 737
 738                 if ( '' == $this->mInterwiki ) {
 739                         $url = $this->getLocalUrl( $query, $variant );
 740
 741                         // Ugly quick hack to avoid duplicate prefixes (bug 4571 etc)
 742                         // Correct fix would be to move the prepending elsewhere.
 743                         if ($wgRequest->getVal('action') != 'render') {
 744                                 $url = $wgServer . $url;
 745                         }
 746                 } else {
 747                         $baseUrl = $this->getInterwikiLink( $this->mInterwiki );
 748
 749                         $namespace = wfUrlencode( $this->getNsText() );
 750                         if ( '' != $namespace ) {
 751                                 # Can this actually happen? Interwikis shouldn't be parsed.
 752                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
 753                                 $namespace .= ':';
 754                         }
 755                         $url = str_replace( '$1', $namespace . $this->mUrlform, $baseUrl );
 756                         $url = wfAppendQuery( $url, $query );
 757                 }
 758
 759                 # Finally, add the fragment.
 760                 $url .= $this->getFragmentForURL();
 761
 762                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
 763                 return $url;
 764         }
 765
 766         /**
 767          * Get a URL with no fragment or server name.  If this page is generated
 768          * with action=render, $wgServer is prepended.
 769          * @param string $query an optional query string; if not specified,
 770          *      $wgArticlePath will be used.
 771          * @param string $variant language variant of url (for sr, zh..)
 772          * @return string the URL
 773          */
 774         public function getLocalURL( $query = '', $variant = false ) {
 775                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
 776                 global $wgVariantArticlePath, $wgContLang, $wgUser;
 777
 778                 // internal links should point to same variant as current page (only anonymous users)
 779                 if($variant == false && $wgContLang->hasVariants() && !$wgUser->isLoggedIn()){
 780                         $pref = $wgContLang->getPreferredVariant(false);
 781                         if($pref != $wgContLang->getCode())
 782                                 $variant = $pref;
 783                 }
 784
 785                 if ( $this->isExternal() ) {
 786                         $url = $this->getFullURL();
 787                         if ( $query ) {
 788                                 // This is currently only used for edit section links in the
 789                                 // context of interwiki transclusion. In theory we should
 790                                 // append the query to the end of any existing query string,
 791                                 // but interwiki transclusion is already broken in that case.
 792                                 $url .= "?$query";
 793                         }
 794                 } else {
 795                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 796                         if ( $query == '' ) {
 797                                 if($variant!=false && $wgContLang->hasVariants()){
 798                                         if($wgVariantArticlePath==false) {
 799                                                 $variantArticlePath =  "$wgScript?title=$1&variant=$2"; // default
 800                                         } else {
 801                                                 $variantArticlePath = $wgVariantArticlePath;
 802                                         }
 803                                         $url = str_replace( '$2', urlencode( $variant ), $variantArticlePath );
 804                                         $url = str_replace( '$1', $dbkey, $url  );
 805                                 }
 806                                 else {
 807                                         $url = str_replace( '$1', $dbkey, $wgArticlePath );
 808                                 }
 809                         } else {
 810                                 global $wgActionPaths;
 811                                 $url = false;
 812                                 $matches = array();
 813                                 if( !empty( $wgActionPaths ) &&
 814                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
 815                                 {
 816                                         $action = urldecode( $matches[2] );
 817                                         if( isset( $wgActionPaths[$action] ) ) {
 818                                                 $query = $matches[1];
 819                                                 if( isset( $matches[4] ) ) $query .= $matches[4];
 820                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
 821                                                 if( $query != '' ) $url .= '?' . $query;
 822                                         }
 823                                 }
 824                                 if ( $url === false ) {
 825                                         if ( $query == '-' ) {
 826                                                 $query = '';
 827                                         }
 828                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
 829                                 }
 830                         }
 831
 832                         // FIXME: this causes breakage in various places when we
 833                         // actually expected a local URL and end up with dupe prefixes.
 834                         if ($wgRequest->getVal('action') == 'render') {
 835                                 $url = $wgServer . $url;
 836                         }
 837                 }
 838                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
 839                 return $url;
 840         }
 841
 842         /**
 843          * Get an HTML-escaped version of the URL form, suitable for
 844          * using in a link, without a server name or fragment
 845          * @param string $query an optional query string
 846          * @return string the URL
 847          */
 848         public function escapeLocalURL( $query = '' ) {
 849                 return htmlspecialchars( $this->getLocalURL( $query ) );
 850         }
 851
 852         /**
 853          * Get an HTML-escaped version of the URL form, suitable for
 854          * using in a link, including the server name and fragment
 855          *
 856          * @return string the URL
 857          * @param string $query an optional query string
 858          */
 859         public function escapeFullURL( $query = '' ) {
 860                 return htmlspecialchars( $this->getFullURL( $query ) );
 861         }
 862
 863         /**
 864          * Get the URL form for an internal link.
 865          * - Used in various Squid-related code, in case we have a different
 866          * internal hostname for the server from the exposed one.
 867          *
 868          * @param string $query an optional query string
 869          * @param string $variant language variant of url (for sr, zh..)
 870          * @return string the URL
 871          */
 872         public function getInternalURL( $query = '', $variant = false ) {
 873                 global $wgInternalServer;
 874                 $url = $wgInternalServer . $this->getLocalURL( $query, $variant );
 875                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
 876                 return $url;
 877         }
 878
 879         /**
 880          * Get the edit URL for this Title
 881          * @return string the URL, or a null string if this is an
 882          *      interwiki link
 883          */
 884         public function getEditURL() {
 885                 if ( '' != $this->mInterwiki ) { return ''; }
 886                 $s = $this->getLocalURL( 'action=edit' );
 887
 888                 return $s;
 889         }
 890
 891         /**
 892          * Get the HTML-escaped displayable text form.
 893          * Used for the title field in <a> tags.
 894          * @return string the text, including any prefixes
 895          */
 896         public function getEscapedText() {
 897                 return htmlspecialchars( $this->getPrefixedText() );
 898         }
 899
 900         /**
 901          * Is this Title interwiki?
 902          * @return boolean
 903          */
 904         public function isExternal() { return ( '' != $this->mInterwiki ); }
 905
 906         /**
 907          * Is this page "semi-protected" - the *only* protection is autoconfirm?
 908          *
 909          * @param string Action to check (default: edit)
 910          * @return bool
 911          */
 912         public function isSemiProtected( $action = 'edit' ) {
 913                 if( $this->exists() ) {
 914                         $restrictions = $this->getRestrictions( $action );
 915                         if( count( $restrictions ) > 0 ) {
 916                                 foreach( $restrictions as $restriction ) {
 917                                         if( strtolower( $restriction ) != 'autoconfirmed' )
 918                                                 return false;
 919                                 }
 920                         } else {
 921                                 # Not protected
 922                                 return false;
 923                         }
 924                         return true;
 925                 } else {
 926                         # If it doesn't exist, it can't be protected
 927                         return false;
 928                 }
 929         }
 930
 931         /**
 932          * Does the title correspond to a protected article?
 933          * @param string $what the action the page is protected from,
 934          * by default checks move and edit
 935          * @return boolean
 936          */
 937         public function isProtected( $action = '' ) {
 938                 global $wgRestrictionLevels;
 939
 940                 # Special pages have inherent protection
 941                 if( $this->getNamespace() == NS_SPECIAL )
 942                         return true;
 943
 944                 # Check regular protection levels
 945                 if( $action == 'edit' || $action == '' ) {
 946                         $r = $this->getRestrictions( 'edit' );
 947                         foreach( $wgRestrictionLevels as $level ) {
 948                                 if( in_array( $level, $r ) && $level != '' ) {
 949                                         return( true );
 950                                 }
 951                         }
 952                 }
 953
 954                 if( $action == 'move' || $action == '' ) {
 955                         $r = $this->getRestrictions( 'move' );
 956                         foreach( $wgRestrictionLevels as $level ) {
 957                                 if( in_array( $level, $r ) && $level != '' ) {
 958                                         return( true );
 959                                 }
 960                         }
 961                 }
 962
 963                 return false;
 964         }
 965
 966         /**
 967          * Is $wgUser is watching this page?
 968          * @return boolean
 969          */
 970         public function userIsWatching() {
 971                 global $wgUser;
 972
 973                 if ( is_null( $this->mWatched ) ) {
 974                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn()) {
 975                                 $this->mWatched = false;
 976                         } else {
 977                                 $this->mWatched = $wgUser->isWatched( $this );
 978                         }
 979                 }
 980                 return $this->mWatched;
 981         }
 982
 983         /**
 984          * Can $wgUser perform $action on this page?
 985          * This skips potentially expensive cascading permission checks.
 986          *
 987          * Suitable for use for nonessential UI controls in common cases, but
 988          * _not_ for functional access control.
 989          *
 990          * May provide false positives, but should never provide a false negative.
 991          *
 992          * @param string $action action that permission needs to be checked for
 993          * @return boolean
 994          */
 995         public function quickUserCan( $action ) {
 996                 return $this->userCan( $action, false );
 997         }
 998
 999         /**
1000          * Determines if $wgUser is unable to edit this page because it has been protected
1001          * by $wgNamespaceProtection.
1002          *
1003          * @return boolean
1004          */
1005         public function isNamespaceProtected() {
1006                 global $wgNamespaceProtection, $wgUser;
1007                 if( isset( $wgNamespaceProtection[ $this->mNamespace ] ) ) {
1008                         foreach( (array)$wgNamespaceProtection[ $this->mNamespace ] as $right ) {
1009                                 if( $right != '' && !$wgUser->isAllowed( $right ) )
1010                                         return true;
1011                         }
1012                 }
1013                 return false;
1014         }
1015
1016         /**
1017          * Can $wgUser perform $action on this page?
1018          * @param string $action action that permission needs to be checked for
1019          * @param bool $doExpensiveQueries Set this to false to avoid doing unnecessary queries.
1020          * @return boolean
1021          */
1022         public function userCan( $action, $doExpensiveQueries = true ) {
1023                 global $wgUser;
1024                 return ( $this->getUserPermissionsErrorsInternal( $action, $wgUser, $doExpensiveQueries ) === array());
1025         }
1026
1027         /**
1028          * Can $user perform $action on this page?
1029          * @param string $action action that permission needs to be checked for
1030          * @param bool $doExpensiveQueries Set this to false to avoid doing unnecessary queries.
1031          * @return array Array of arrays of the arguments to wfMsg to explain permissions problems.
1032          */
1033         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true ) {
1034                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1035
1036                 global $wgContLang;
1037                 global $wgLang;
1038
1039                 if ( wfReadOnly() && $action != 'read' ) {
1040                         global $wgReadOnly;
1041                         $errors[] = array( 'readonlytext', $wgReadOnly );
1042                 }
1043
1044                 global $wgEmailConfirmToEdit, $wgUser;
1045
1046                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() )
1047                 {
1048                         $errors[] = array( 'confirmedittext' );
1049                 }
1050
1051                 if ( $user->isBlockedFrom( $this ) ) {
1052                         $block = $user->mBlock;
1053
1054                         // This is from OutputPage::blockedPage
1055                         // Copied at r23888 by werdna
1056
1057                         $id = $user->blockedBy();
1058                         $reason = $user->blockedFor();
1059                         if( $reason == '' ) {
1060                                 $reason = wfMsg( 'blockednoreason' );
1061                         }
1062                         $ip = wfGetIP();
1063
1064                         if ( is_numeric( $id ) ) {
1065                                 $name = User::whoIs( $id );
1066                         } else {
1067                                 $name = $id;
1068                         }
1069
1070                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1071                         $blockid = $block->mId;
1072                         $blockExpiry = $user->mBlock->mExpiry;
1073                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $user->mBlock->mTimestamp ), true );
1074
1075                         if ( $blockExpiry == 'infinity' ) {
1076                                 // Entry in database (table ipblocks) is 'infinity' but 'ipboptions' uses 'infinite' or 'indefinite'
1077                                 $scBlockExpiryOptions = wfMsg( 'ipboptions' );
1078
1079                                 foreach ( explode( ',', $scBlockExpiryOptions ) as $option ) {
1080                                         if ( strpos( $option, ':' ) == false )
1081                                                 continue;
1082
1083                                         list ($show, $value) = explode( ":", $option );
1084
1085                                         if ( $value == 'infinite' || $value == 'indefinite' ) {
1086                                                 $blockExpiry = $show;
1087                                                 break;
1088                                         }
1089                                 }
1090                         } else {
1091                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1092                         }
1093
1094                         $intended = $user->mBlock->mAddress;
1095
1096                         $errors[] = array ( ($block->mAuto ? 'autoblockedtext' : 'blockedtext'), $link, $reason, $ip, $name, $blockid, $blockExpiry, $intended, $blockTimestamp );
1097                 }
1098
1099                 return $errors;
1100         }
1101
1102         /**
1103          * Can $user perform $action on this page?
1104          * This is an internal function, which checks ONLY that previously checked by userCan (i.e. it leaves out checks on wfReadOnly() and blocks)
1105          * @param string $action action that permission needs to be checked for
1106          * @param bool $doExpensiveQueries Set this to false to avoid doing unnecessary queries.
1107          * @return array Array of arrays of the arguments to wfMsg to explain permissions problems.
1108          */
1109         private function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true ) {
1110                 $fname = 'Title::userCan';
1111                 wfProfileIn( $fname );
1112
1113                 $errors = array();
1114
1115                 // Use getUserPermissionsErrors instead
1116                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1117                         return $result ? array() : array( array( 'badaccess-group0' ) );
1118                 }
1119
1120                 if (!wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1121                         if ($result != array() && is_array($result) && !is_array($result[0]))
1122                                 $errors[] = $result; # A single array representing an error
1123                         else if (is_array($result) && is_array($result[0]))
1124                                 $errors = array_merge( $errors, $result ); # A nested array representing multiple errors
1125                         else if ($result != '' && $result != null && $result !== true && $result !== false)
1126                                 $errors[] = array($result); # A string representing a message-id
1127                         else if ($result === false )
1128                                 $errors[] = array('badaccess-group0'); # a generic "We don't want them to do that"
1129                 }
1130
1131                 if( NS_SPECIAL == $this->mNamespace ) {
1132                         $errors[] = array('ns-specialprotected');
1133                 }
1134
1135                 if ( $this->isNamespaceProtected() ) {
1136                         $ns = $this->getNamespace() == NS_MAIN
1137                                 ? wfMsg( 'nstab-main' )
1138                                 : $this->getNsText();
1139                         $errors[] = (NS_MEDIAWIKI == $this->mNamespace
1140                                 ? array('protectedinterface')
1141                                 : array( 'namespaceprotected',  $ns ) );
1142                 }
1143
1144                 if( $this->mDbkeyform == '_' ) {
1145                         # FIXME: Is this necessary? Shouldn't be allowed anyway...
1146                         $errors[] = array('badaccess-group0');
1147                 }
1148
1149                 # protect css/js subpages of user pages
1150                 # XXX: this might be better using restrictions
1151                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssJsSubpage() from working
1152                 if( $this->isCssJsSubpage()
1153                         && !$user->isAllowed('editusercssjs')
1154                         && !preg_match('/^'.preg_quote($user->getName(), '/').'\//', $this->mTextform) ) {
1155                         $errors[] = array('customcssjsprotected');
1156                 }
1157
1158                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1159                         # We /could/ use the protection level on the source page, but it's fairly ugly
1160                         #  as we have to establish a precedence hierarchy for pages included by multiple
1161                         #  cascade-protected pages. So just restrict it to people with 'protect' permission,
1162                         #  as they could remove the protection anyway.
1163                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1164                         # Cascading protection depends on more than this page...
1165                         # Several cascading protected pages may include this page...
1166                         # Check each cascading level
1167                         # This is only for protection restrictions, not for all actions
1168                         if( $cascadingSources > 0 && isset($restrictions[$action]) ) {
1169                                 foreach( $restrictions[$action] as $right ) {
1170                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1171                                         if( '' != $right && !$user->isAllowed( $right ) ) {
1172                                                 $pages = '';
1173                                                 foreach( $cascadingSources as $page )
1174                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1175                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1176                                         }
1177                                 }
1178                         }
1179                 }
1180
1181                 foreach( $this->getRestrictions($action) as $right ) {
1182                         // Backwards compatibility, rewrite sysop -> protect
1183                         if ( $right == 'sysop' ) {
1184                                 $right = 'protect';
1185                         }
1186                         if( '' != $right && !$user->isAllowed( $right ) ) {
1187                                 $errors[] = array( 'protectedpagetext', $right );
1188                         }
1189                 }
1190
1191                 if( $action == 'create' ) {
1192                         if( (  $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1193                                 ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1194                                 $errors[] = $user->isAnon() ? array ('nocreatetext') : array ('nocreate-loggedin');
1195                         }
1196                 } elseif( $action == 'move' && !( $this->isMovable() && $user->isAllowed( 'move' ) ) ) {
1197                         $errors[] = $user->isAnon() ? array ( 'movenologintext' ) : array ('movenotallowed');
1198         } else if ( !$user->isAllowed( $action ) ) {
1199                         $return = null;
1200                     $groups = array();
1201                         global $wgGroupPermissions;
1202                         foreach( $wgGroupPermissions as $key => $value ) {
1203                             if( isset( $value[$action] ) && $value[$action] == true ) {
1204                                 $groupName = User::getGroupName( $key );
1205                                 $groupPage = User::getGroupPage( $key );
1206                                 if( $groupPage ) {
1207                                     $groups[] = '[['.$groupPage->getPrefixedText().'|'.$groupName.']]';
1208                                 } else {
1209                                     $groups[] = $groupName;
1210                                 }
1211                             }
1212                         }
1213                         $n = count( $groups );
1214                         $groups = implode( ', ', $groups );
1215                         switch( $n ) {
1216                             case 0:
1217                             case 1:
1218                             case 2:
1219                                 $return = array( "badaccess-group$n", $groups );
1220                                 break;
1221                             default:
1222                                 $return = array( 'badaccess-groups', $groups );
1223                         }
1224                         $errors[] = $return;
1225                 }
1226
1227                 wfProfileOut( $fname );
1228                 return $errors;
1229         }
1230
1231         /**
1232          * Can $wgUser edit this page?
1233          * @return boolean
1234          * @deprecated use userCan('edit')
1235          */
1236         public function userCanEdit( $doExpensiveQueries = true ) {
1237                 return $this->userCan( 'edit', $doExpensiveQueries );
1238         }
1239
1240         /**
1241          * Can $wgUser create this page?
1242          * @return boolean
1243          * @deprecated use userCan('create')
1244          */
1245         public function userCanCreate( $doExpensiveQueries = true ) {
1246                 return $this->userCan( 'create', $doExpensiveQueries );
1247         }
1248
1249         /**
1250          * Can $wgUser move this page?
1251          * @return boolean
1252          * @deprecated use userCan('move')
1253          */
1254         public function userCanMove( $doExpensiveQueries = true ) {
1255                 return $this->userCan( 'move', $doExpensiveQueries );
1256         }
1257
1258         /**
1259          * Would anybody with sufficient privileges be able to move this page?
1260          * Some pages just aren't movable.
1261          *
1262          * @return boolean
1263          */
1264         public function isMovable() {
1265                 return Namespace::isMovable( $this->getNamespace() )
1266                         && $this->getInterwiki() == '';
1267         }
1268
1269         /**
1270          * Can $wgUser read this page?
1271          * @return boolean
1272          * @todo fold these checks into userCan()
1273          */
1274         public function userCanRead() {
1275                 global $wgUser;
1276
1277                 $result = null;
1278                 wfRunHooks( 'userCan', array( &$this, &$wgUser, 'read', &$result ) );
1279                 if ( $result !== null ) {
1280                         return $result;
1281                 }
1282
1283                 if( $wgUser->isAllowed( 'read' ) ) {
1284                         return true;
1285                 } else {
1286                         global $wgWhitelistRead;
1287
1288                         /**
1289                          * Always grant access to the login page.
1290                          * Even anons need to be able to log in.
1291                         */
1292                         if( $this->isSpecial( 'Userlogin' ) || $this->isSpecial( 'Resetpass' ) ) {
1293                                 return true;
1294                         }
1295
1296                         /**
1297                          * Bail out if there isn't whitelist
1298                          */
1299                         if( !is_array($wgWhitelistRead) ) {
1300                                 return false;
1301                         }
1302
1303                         /**
1304                          * Check for explicit whitelisting
1305                          */
1306                         $name = $this->getPrefixedText();
1307                         if( in_array( $name, $wgWhitelistRead, true ) )
1308                                 return true;
1309
1310                         /**
1311                          * Old settings might have the title prefixed with
1312                          * a colon for main-namespace pages
1313                          */
1314                         if( $this->getNamespace() == NS_MAIN ) {
1315                                 if( in_array( ':' . $name, $wgWhitelistRead ) )
1316                                         return true;
1317                         }
1318
1319                         /**
1320                          * If it's a special page, ditch the subpage bit
1321                          * and check again
1322                          */
1323                         if( $this->getNamespace() == NS_SPECIAL ) {
1324                                 $name = $this->getDBKey();
1325                                 list( $name, /* $subpage */) = SpecialPage::resolveAliasWithSubpage( $name );
1326                                 if ( $name === false ) {
1327                                         # Invalid special page, but we show standard login required message
1328                                         return false;
1329                                 }
1330
1331                                 $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
1332                                 if( in_array( $pure, $wgWhitelistRead, true ) )
1333                                         return true;
1334                         }
1335
1336                 }
1337                 return false;
1338         }
1339
1340         /**
1341          * Is this a talk page of some sort?
1342          * @return bool
1343          */
1344         public function isTalkPage() {
1345                 return Namespace::isTalk( $this->getNamespace() );
1346         }
1347
1348         /**
1349          * Is this a subpage?
1350          * @return bool
1351          */
1352         public function isSubpage() {
1353                 global $wgNamespacesWithSubpages;
1354
1355                 if( isset( $wgNamespacesWithSubpages[ $this->mNamespace ] ) ) {
1356                         return ( strpos( $this->getText(), '/' ) !== false && $wgNamespacesWithSubpages[ $this->mNamespace ] == true );
1357                 } else {
1358                         return false;
1359                 }
1360         }
1361
1362         /**
1363          * Could this page contain custom CSS or JavaScript, based
1364          * on the title?
1365          *
1366          * @return bool
1367          */
1368         public function isCssOrJsPage() {
1369                 return $this->mNamespace == NS_MEDIAWIKI
1370                         && preg_match( '!\.(?:css|js)$!u', $this->mTextform ) > 0;
1371         }
1372
1373         /**
1374          * Is this a .css or .js subpage of a user page?
1375          * @return bool
1376          */
1377         public function isCssJsSubpage() {
1378                 return ( NS_USER == $this->mNamespace and preg_match("/\\/.*\\.(?:css|js)$/", $this->mTextform ) );
1379         }
1380         /**
1381          * Is this a *valid* .css or .js subpage of a user page?
1382          * Check that the corresponding skin exists
1383          */
1384         public function isValidCssJsSubpage() {
1385                 if ( $this->isCssJsSubpage() ) {
1386                         $skinNames = Skin::getSkinNames();
1387                         return array_key_exists( $this->getSkinFromCssJsSubpage(), $skinNames );
1388                 } else {
1389                         return false;
1390                 }
1391         }
1392         /**
1393          * Trim down a .css or .js subpage title to get the corresponding skin name
1394          */
1395         public function getSkinFromCssJsSubpage() {
1396                 $subpage = explode( '/', $this->mTextform );
1397                 $subpage = $subpage[ count( $subpage ) - 1 ];
1398                 return( str_replace( array( '.css', '.js' ), array( '', '' ), $subpage ) );
1399         }
1400         /**
1401          * Is this a .css subpage of a user page?
1402          * @return bool
1403          */
1404         public function isCssSubpage() {
1405                 return ( NS_USER == $this->mNamespace and preg_match("/\\/.*\\.css$/", $this->mTextform ) );
1406         }
1407         /**
1408          * Is this a .js subpage of a user page?
1409          * @return bool
1410          */
1411         public function isJsSubpage() {
1412                 return ( NS_USER == $this->mNamespace and preg_match("/\\/.*\\.js$/", $this->mTextform ) );
1413         }
1414         /**
1415          * Protect css/js subpages of user pages: can $wgUser edit
1416          * this page?
1417          *
1418          * @return boolean
1419          * @todo XXX: this might be better using restrictions
1420          */
1421         public function userCanEditCssJsSubpage() {
1422                 global $wgUser;
1423                 return ( $wgUser->isAllowed('editusercssjs') or preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1424         }
1425
1426         /**
1427          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
1428          *
1429          * @return bool If the page is subject to cascading restrictions.
1430          */
1431         public function isCascadeProtected() {
1432                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
1433                 return ( $sources > 0 );
1434         }
1435
1436         /**
1437          * Cascading protection: Get the source of any cascading restrictions on this page.
1438          *
1439          * @param $get_pages bool Whether or not to retrieve the actual pages that the restrictions have come from.
1440          * @return array( mixed title array, restriction array)
1441          * Array of the Title objects of the pages from which cascading restrictions have come, false for none, or true if such restrictions exist, but $get_pages was not set.
1442          * The restriction array is an array of each type, each of which contains an array of unique groups
1443          */
1444         public function getCascadeProtectionSources( $get_pages = true ) {
1445                 global $wgEnableCascadingProtection, $wgRestrictionTypes;
1446
1447                 # Define our dimension of restrictions types
1448                 $pagerestrictions = array();
1449                 foreach( $wgRestrictionTypes as $action )
1450                         $pagerestrictions[$action] = array();
1451
1452                 if (!$wgEnableCascadingProtection)
1453                         return array( false, $pagerestrictions );
1454
1455                 if ( isset( $this->mCascadeSources ) && $get_pages ) {
1456                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
1457                 } else if ( isset( $this->mHasCascadingRestrictions ) && !$get_pages ) {
1458                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
1459                 }
1460
1461                 wfProfileIn( __METHOD__ );
1462
1463                 $dbr = wfGetDb( DB_SLAVE );
1464
1465                 if ( $this->getNamespace() == NS_IMAGE ) {
1466                         $tables = array ('imagelinks', 'page_restrictions');
1467                         $where_clauses = array(
1468                                 'il_to' => $this->getDBkey(),
1469                                 'il_from=pr_page',
1470                                 'pr_cascade' => 1 );
1471                 } else {
1472                         $tables = array ('templatelinks', 'page_restrictions');
1473                         $where_clauses = array(
1474                                 'tl_namespace' => $this->getNamespace(),
1475                                 'tl_title' => $this->getDBkey(),
1476                                 'tl_from=pr_page',
1477                                 'pr_cascade' => 1 );
1478                 }
1479
1480                 if ( $get_pages ) {
1481                         $cols = array('pr_page', 'page_namespace', 'page_title', 'pr_expiry', 'pr_type', 'pr_level' );
1482                         $where_clauses[] = 'page_id=pr_page';
1483                         $tables[] = 'page';
1484                 } else {
1485                         $cols = array( 'pr_expiry' );
1486                 }
1487
1488                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
1489
1490                 $sources = $get_pages ? array() : false;
1491                 $now = wfTimestampNow();
1492                 $purgeExpired = false;
1493
1494                 while( $row = $dbr->fetchObject( $res ) ) {
1495                         $expiry = Block::decodeExpiry( $row->pr_expiry );
1496                         if( $expiry > $now ) {
1497                                 if ($get_pages) {
1498                                         $page_id = $row->pr_page;
1499                                         $page_ns = $row->page_namespace;
1500                                         $page_title = $row->page_title;
1501                                         $sources[$page_id] = Title::makeTitle($page_ns, $page_title);
1502                                         # Add groups needed for each restriction type if its not already there
1503                                         # Make sure this restriction type still exists
1504                                         if ( isset($pagerestrictions[$row->pr_type]) && !in_array($row->pr_level, $pagerestrictions[$row->pr_type]) ) {
1505                                                 $pagerestrictions[$row->pr_type][]=$row->pr_level;
1506                                         }
1507                                 } else {
1508                                         $sources = true;
1509                                 }
1510                         } else {
1511                                 // Trigger lazy purge of expired restrictions from the db
1512                                 $purgeExpired = true;
1513                         }
1514                 }
1515                 if( $purgeExpired ) {
1516                         Title::purgeExpiredRestrictions();
1517                 }
1518
1519                 wfProfileOut( __METHOD__ );
1520
1521                 if ( $get_pages ) {
1522                         $this->mCascadeSources = $sources;
1523                         $this->mCascadingRestrictions = $pagerestrictions;
1524                 } else {
1525                         $this->mHasCascadingRestrictions = $sources;
1526                 }
1527
1528                 return array( $sources, $pagerestrictions );
1529         }
1530
1531         function areRestrictionsCascading() {
1532                 if (!$this->mRestrictionsLoaded) {
1533                         $this->loadRestrictions();
1534                 }
1535
1536                 return $this->mCascadeRestriction;
1537         }
1538
1539         /**
1540          * Loads a string into mRestrictions array
1541          * @param resource $res restrictions as an SQL result.
1542          */
1543         private function loadRestrictionsFromRow( $res, $oldFashionedRestrictions = NULL ) {
1544                 $dbr = wfGetDb( DB_SLAVE );
1545
1546                 $this->mRestrictions['edit'] = array();
1547                 $this->mRestrictions['move'] = array();
1548
1549                 # Backwards-compatibility: also load the restrictions from the page record (old format).
1550
1551                 if ( $oldFashionedRestrictions == NULL ) {
1552                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions', array( 'page_id' => $this->getArticleId() ), __METHOD__ );
1553                 }
1554
1555                 if ($oldFashionedRestrictions != '') {
1556
1557                         foreach( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
1558                                 $temp = explode( '=', trim( $restrict ) );
1559                                 if(count($temp) == 1) {
1560                                         // old old format should be treated as edit/move restriction
1561                                         $this->mRestrictions["edit"] = explode( ',', trim( $temp[0] ) );
1562                                         $this->mRestrictions["move"] = explode( ',', trim( $temp[0] ) );
1563                                 } else {
1564                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
1565                                 }
1566                         }
1567
1568                         $this->mOldRestrictions = true;
1569                         $this->mCascadeRestriction = false;
1570                         $this->mRestrictionsExpiry = Block::decodeExpiry('');
1571
1572                 }
1573
1574                 if( $dbr->numRows( $res ) ) {
1575                         # Current system - load second to make them override.
1576                         $now = wfTimestampNow();
1577                         $purgeExpired = false;
1578
1579                         while ($row = $dbr->fetchObject( $res ) ) {
1580                                 # Cycle through all the restrictions.
1581
1582                                 // This code should be refactored, now that it's being used more generally,
1583                                 // But I don't really see any harm in leaving it in Block for now -werdna
1584                                 $expiry = Block::decodeExpiry( $row->pr_expiry );
1585
1586                                 // Only apply the restrictions if they haven't expired!
1587                                 if ( !$expiry || $expiry > $now ) {
1588                                         $this->mRestrictionsExpiry = $expiry;
1589                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
1590
1591                                         $this->mCascadeRestriction |= $row->pr_cascade;
1592                                 } else {
1593                                         // Trigger a lazy purge of expired restrictions
1594                                         $purgeExpired = true;
1595                                 }
1596                         }
1597
1598                         if( $purgeExpired ) {
1599                                 Title::purgeExpiredRestrictions();
1600                         }
1601                 }
1602
1603                 $this->mRestrictionsLoaded = true;
1604         }
1605
1606         public function loadRestrictions( $oldFashionedRestrictions = NULL ) {
1607                 if( !$this->mRestrictionsLoaded ) {
1608                         $dbr = wfGetDB( DB_SLAVE );
1609
1610                         $res = $dbr->select( 'page_restrictions', '*',
1611                                 array ( 'pr_page' => $this->getArticleId() ), __METHOD__ );
1612
1613                         $this->loadRestrictionsFromRow( $res, $oldFashionedRestrictions );
1614                 }
1615         }
1616
1617         /**
1618          * Purge expired restrictions from the page_restrictions table
1619          */
1620         static function purgeExpiredRestrictions() {
1621                 $dbw = wfGetDB( DB_MASTER );
1622                 $dbw->delete( 'page_restrictions',
1623                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
1624                         __METHOD__ );
1625         }
1626
1627         /**
1628          * Accessor/initialisation for mRestrictions
1629          *
1630          * @param string $action action that permission needs to be checked for
1631          * @return array the array of groups allowed to edit this article
1632          */
1633         public function getRestrictions( $action ) {
1634                 if( $this->exists() ) {
1635                         if( !$this->mRestrictionsLoaded ) {
1636                                 $this->loadRestrictions();
1637                         }
1638                         return isset( $this->mRestrictions[$action] )
1639                                         ? $this->mRestrictions[$action]
1640                                         : array();
1641                 } else {
1642                         return array();
1643                 }
1644         }
1645
1646         /**
1647          * Is there a version of this page in the deletion archive?
1648          * @return int the number of archived revisions
1649          */
1650         public function isDeleted() {
1651                 $fname = 'Title::isDeleted';
1652                 if ( $this->getNamespace() < 0 ) {
1653                         $n = 0;
1654                 } else {
1655                         $dbr = wfGetDB( DB_SLAVE );
1656                         $n = $dbr->selectField( 'archive', 'COUNT(*)', array( 'ar_namespace' => $this->getNamespace(),
1657                                 'ar_title' => $this->getDBkey() ), $fname );
1658                         if( $this->getNamespace() == NS_IMAGE ) {
1659                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
1660                                         array( 'fa_name' => $this->getDBkey() ), $fname );
1661                         }
1662                 }
1663                 return (int)$n;
1664         }
1665
1666         /**
1667          * Get the article ID for this Title from the link cache,
1668          * adding it if necessary
1669          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select
1670          *      for update
1671          * @return int the ID
1672          */
1673         public function getArticleID( $flags = 0 ) {
1674                 $linkCache =& LinkCache::singleton();
1675                 if ( $flags & GAID_FOR_UPDATE ) {
1676                         $oldUpdate = $linkCache->forUpdate( true );
1677                         $this->mArticleID = $linkCache->addLinkObj( $this );
1678                         $linkCache->forUpdate( $oldUpdate );
1679                 } else {
1680                         if ( -1 == $this->mArticleID ) {
1681                                 $this->mArticleID = $linkCache->addLinkObj( $this );
1682                         }
1683                 }
1684                 return $this->mArticleID;
1685         }
1686
1687         public function getLatestRevID() {
1688                 if ($this->mLatestID !== false)
1689                         return $this->mLatestID;
1690
1691                 $db = wfGetDB(DB_SLAVE);
1692                 return $this->mLatestID = $db->selectField( 'revision',
1693                         "max(rev_id)",
1694                         array('rev_page' => $this->getArticleID()),
1695                         'Title::getLatestRevID' );
1696         }
1697
1698         /**
1699          * This clears some fields in this object, and clears any associated
1700          * keys in the "bad links" section of the link cache.
1701          *
1702          * - This is called from Article::insertNewArticle() to allow
1703          * loading of the new page_id. It's also called from
1704          * Article::doDeleteArticle()
1705          *
1706          * @param int $newid the new Article ID
1707          */
1708         public function resetArticleID( $newid ) {
1709                 $linkCache =& LinkCache::singleton();
1710                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
1711
1712                 if ( 0 == $newid ) { $this->mArticleID = -1; }
1713                 else { $this->mArticleID = $newid; }
1714                 $this->mRestrictionsLoaded = false;
1715                 $this->mRestrictions = array();
1716         }
1717
1718         /**
1719          * Updates page_touched for this page; called from LinksUpdate.php
1720          * @return bool true if the update succeded
1721          */
1722         public function invalidateCache() {
1723                 global $wgUseFileCache;
1724
1725                 if ( wfReadOnly() ) {
1726                         return;
1727                 }
1728
1729                 $dbw = wfGetDB( DB_MASTER );
1730                 $success = $dbw->update( 'page',
1731                         array( /* SET */
1732                                 'page_touched' => $dbw->timestamp()
1733                         ), array( /* WHERE */
1734                                 'page_namespace' => $this->getNamespace() ,
1735                                 'page_title' => $this->getDBkey()
1736                         ), 'Title::invalidateCache'
1737                 );
1738
1739                 if ($wgUseFileCache) {
1740                         $cache = new HTMLFileCache($this);
1741                         @unlink($cache->fileCacheName());
1742                 }
1743
1744                 return $success;
1745         }
1746
1747         /**
1748          * Prefix some arbitrary text with the namespace or interwiki prefix
1749          * of this object
1750          *
1751          * @param string $name the text
1752          * @return string the prefixed text
1753          * @private
1754          */
1755         /* private */ function prefix( $name ) {
1756                 $p = '';
1757                 if ( '' != $this->mInterwiki ) {
1758                         $p = $this->mInterwiki . ':';
1759                 }
1760                 if ( 0 != $this->mNamespace ) {
1761                         $p .= $this->getNsText() . ':';
1762                 }
1763                 return $p . $name;
1764         }
1765
1766         /**
1767          * Secure and split - main initialisation function for this object
1768          *
1769          * Assumes that mDbkeyform has been set, and is urldecoded
1770          * and uses underscores, but not otherwise munged.  This function
1771          * removes illegal characters, splits off the interwiki and
1772          * namespace prefixes, sets the other forms, and canonicalizes
1773          * everything.
1774          * @return bool true on success
1775          */
1776         private function secureAndSplit() {
1777                 global $wgContLang, $wgLocalInterwiki, $wgCapitalLinks;
1778
1779                 # Initialisation
1780                 static $rxTc = false;
1781                 if( !$rxTc ) {
1782                         # % is needed as well
1783                         $rxTc = '/[^' . Title::legalChars() . ']|%[0-9A-Fa-f]{2}/S';
1784                 }
1785
1786                 $this->mInterwiki = $this->mFragment = '';
1787                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
1788
1789                 $dbkey = $this->mDbkeyform;
1790
1791                 # Strip Unicode bidi override characters.
1792                 # Sometimes they slip into cut-n-pasted page titles, where the
1793                 # override chars get included in list displays.
1794                 $dbkey = str_replace( "\xE2\x80\x8E", '', $dbkey ); // 200E LEFT-TO-RIGHT MARK
1795                 $dbkey = str_replace( "\xE2\x80\x8F", '', $dbkey ); // 200F RIGHT-TO-LEFT MARK
1796
1797                 # Clean up whitespace
1798                 #
1799                 $dbkey = preg_replace( '/[ _]+/', '_', $dbkey );
1800                 $dbkey = trim( $dbkey, '_' );
1801
1802                 if ( '' == $dbkey ) {
1803                         return false;
1804                 }
1805
1806                 if( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
1807                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
1808                         return false;
1809                 }
1810
1811                 $this->mDbkeyform = $dbkey;
1812
1813                 # Initial colon indicates main namespace rather than specified default
1814                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
1815                 if ( ':' == $dbkey{0} ) {
1816                         $this->mNamespace = NS_MAIN;
1817                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
1818                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
1819                 }
1820
1821                 # Namespace or interwiki prefix
1822                 $firstPass = true;
1823                 do {
1824                         $m = array();
1825                         if ( preg_match( "/^(.+?)_*:_*(.*)$/S", $dbkey, $m ) ) {
1826                                 $p = $m[1];
1827                                 if ( $ns = $wgContLang->getNsIndex( $p )) {
1828                                         # Ordinary namespace
1829                                         $dbkey = $m[2];
1830                                         $this->mNamespace = $ns;
1831                                 } elseif( $this->getInterwikiLink( $p ) ) {
1832                                         if( !$firstPass ) {
1833                                                 # Can't make a local interwiki link to an interwiki link.
1834                                                 # That's just crazy!
1835                                                 return false;
1836                                         }
1837
1838                                         # Interwiki link
1839                                         $dbkey = $m[2];
1840                                         $this->mInterwiki = $wgContLang->lc( $p );
1841
1842                                         # Redundant interwiki prefix to the local wiki
1843                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
1844                                                 if( $dbkey == '' ) {
1845                                                         # Can't have an empty self-link
1846                                                         return false;
1847                                                 }
1848                                                 $this->mInterwiki = '';
1849                                                 $firstPass = false;
1850                                                 # Do another namespace split...
1851                                                 continue;
1852                                         }
1853
1854                                         # If there's an initial colon after the interwiki, that also
1855                                         # resets the default namespace
1856                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
1857                                                 $this->mNamespace = NS_MAIN;
1858                                                 $dbkey = substr( $dbkey, 1 );
1859                                         }
1860                                 }
1861                                 # If there's no recognized interwiki or namespace,
1862                                 # then let the colon expression be part of the title.
1863                         }
1864                         break;
1865                 } while( true );
1866
1867                 # We already know that some pages won't be in the database!
1868                 #
1869                 if ( '' != $this->mInterwiki || NS_SPECIAL == $this->mNamespace ) {
1870                         $this->mArticleID = 0;
1871                 }
1872                 $fragment = strstr( $dbkey, '#' );
1873                 if ( false !== $fragment ) {
1874                         $this->setFragment( $fragment );
1875                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
1876                         # remove whitespace again: prevents "Foo_bar_#"
1877                         # becoming "Foo_bar_"
1878                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
1879                 }
1880
1881                 # Reject illegal characters.
1882                 #
1883                 if( preg_match( $rxTc, $dbkey ) ) {
1884                         return false;
1885                 }
1886
1887                 /**
1888                  * Pages with "/./" or "/../" appearing in the URLs will
1889                  * often be unreachable due to the way web browsers deal
1890                  * with 'relative' URLs. Forbid them explicitly.
1891                  */
1892                 if ( strpos( $dbkey, '.' ) !== false &&
1893                      ( $dbkey === '.' || $dbkey === '..' ||
1894                        strpos( $dbkey, './' ) === 0  ||
1895                        strpos( $dbkey, '../' ) === 0 ||
1896                        strpos( $dbkey, '/./' ) !== false ||
1897                        strpos( $dbkey, '/../' ) !== false ) )
1898                 {
1899                         return false;
1900                 }
1901
1902                 /**
1903                  * Magic tilde sequences? Nu-uh!
1904                  */
1905                 if( strpos( $dbkey, '~~~' ) !== false ) {
1906                         return false;
1907                 }
1908
1909                 /**
1910                  * Limit the size of titles to 255 bytes.
1911                  * This is typically the size of the underlying database field.
1912                  * We make an exception for special pages, which don't need to be stored
1913                  * in the database, and may edge over 255 bytes due to subpage syntax
1914                  * for long titles, e.g. [[Special:Block/Long name]]
1915                  */
1916                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
1917                   strlen( $dbkey ) > 512 )
1918                 {
1919                         return false;
1920                 }
1921
1922                 /**
1923                  * Normally, all wiki links are forced to have
1924                  * an initial capital letter so [[foo]] and [[Foo]]
1925                  * point to the same place.
1926                  *
1927                  * Don't force it for interwikis, since the other
1928                  * site might be case-sensitive.
1929                  */
1930                 $this->mUserCaseDBKey = $dbkey;
1931                 if( $wgCapitalLinks && $this->mInterwiki == '') {
1932                         $dbkey = $wgContLang->ucfirst( $dbkey );
1933                 }
1934
1935                 /**
1936                  * Can't make a link to a namespace alone...
1937                  * "empty" local links can only be self-links
1938                  * with a fragment identifier.
1939                  */
1940                 if( $dbkey == '' &&
1941                         $this->mInterwiki == '' &&
1942                         $this->mNamespace != NS_MAIN ) {
1943                         return false;
1944                 }
1945                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
1946                 // IP names are not allowed for accounts, and can only be referring to
1947                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
1948                 // there are numerous ways to present the same IP. Having sp:contribs scan
1949                 // them all is silly and having some show the edits and others not is
1950                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
1951                 $dbkey = ($this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK) ?
1952                         IP::sanitizeIP( $dbkey ) : $dbkey;
1953                 // Any remaining initial :s are illegal.
1954                 if ( $dbkey !== '' && ':' == $dbkey{0} ) {
1955                         return false;
1956                 }
1957
1958                 # Fill fields
1959                 $this->mDbkeyform = $dbkey;
1960                 $this->mUrlform = wfUrlencode( $dbkey );
1961
1962                 $this->mTextform = str_replace( '_', ' ', $dbkey );
1963
1964                 return true;
1965         }
1966
1967         /**
1968          * Set the fragment for this title
1969          * This is kind of bad, since except for this rarely-used function, Title objects
1970          * are immutable. The reason this is here is because it's better than setting the
1971          * members directly, which is what Linker::formatComment was doing previously.
1972          *
1973          * @param string $fragment text
1974          * @todo clarify whether access is supposed to be public (was marked as "kind of public")
1975          */
1976         public function setFragment( $fragment ) {
1977                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
1978         }
1979
1980         /**
1981          * Get a Title object associated with the talk page of this article
1982          * @return Title the object for the talk page
1983          */
1984         public function getTalkPage() {
1985                 return Title::makeTitle( Namespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1986         }
1987
1988         /**
1989          * Get a title object associated with the subject page of this
1990          * talk page
1991          *
1992          * @return Title the object for the subject page
1993          */
1994         public function getSubjectPage() {
1995                 return Title::makeTitle( Namespace::getSubject( $this->getNamespace() ), $this->getDBkey() );
1996         }
1997
1998         /**
1999          * Get an array of Title objects linking to this Title
2000          * Also stores the IDs in the link cache.
2001          *
2002          * WARNING: do not use this function on arbitrary user-supplied titles!
2003          * On heavily-used templates it will max out the memory.
2004          *
2005          * @param string $options may be FOR UPDATE
2006          * @return array the Title objects linking here
2007          */
2008         public function getLinksTo( $options = '', $table = 'pagelinks', $prefix = 'pl' ) {
2009                 $linkCache =& LinkCache::singleton();
2010
2011                 if ( $options ) {
2012                         $db = wfGetDB( DB_MASTER );
2013                 } else {
2014                         $db = wfGetDB( DB_SLAVE );
2015                 }
2016
2017                 $res = $db->select( array( 'page', $table ),
2018                         array( 'page_namespace', 'page_title', 'page_id' ),
2019                         array(
2020                                 "{$prefix}_from=page_id",
2021                                 "{$prefix}_namespace" => $this->getNamespace(),
2022                                 "{$prefix}_title"     => $this->getDbKey() ),
2023                         'Title::getLinksTo',
2024                         $options );
2025
2026                 $retVal = array();
2027                 if ( $db->numRows( $res ) ) {
2028                         while ( $row = $db->fetchObject( $res ) ) {
2029                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
2030                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj );
2031                                         $retVal[] = $titleObj;
2032                                 }
2033                         }
2034                 }
2035                 $db->freeResult( $res );
2036                 return $retVal;
2037         }
2038
2039         /**
2040          * Get an array of Title objects using this Title as a template
2041          * Also stores the IDs in the link cache.
2042          *
2043          * WARNING: do not use this function on arbitrary user-supplied titles!
2044          * On heavily-used templates it will max out the memory.
2045          *
2046          * @param string $options may be FOR UPDATE
2047          * @return array the Title objects linking here
2048          */
2049         public function getTemplateLinksTo( $options = '' ) {
2050                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
2051         }
2052
2053         /**
2054          * Get an array of Title objects referring to non-existent articles linked from this page
2055          *
2056          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
2057          * @param string $options may be FOR UPDATE
2058          * @return array the Title objects
2059          */
2060         public function getBrokenLinksFrom( $options = '' ) {
2061                 if ( $this->getArticleId() == 0 ) {
2062                         # All links from article ID 0 are false positives
2063                         return array();
2064                 }
2065
2066                 if ( $options ) {
2067                         $db = wfGetDB( DB_MASTER );
2068                 } else {
2069                         $db = wfGetDB( DB_SLAVE );
2070                 }
2071
2072                 $res = $db->safeQuery(
2073                           "SELECT pl_namespace, pl_title
2074                              FROM !
2075                         LEFT JOIN !
2076                                ON pl_namespace=page_namespace
2077                               AND pl_title=page_title
2078                             WHERE pl_from=?
2079                               AND page_namespace IS NULL
2080                                   !",
2081                         $db->tableName( 'pagelinks' ),
2082                         $db->tableName( 'page' ),
2083                         $this->getArticleId(),
2084                         $options );
2085
2086                 $retVal = array();
2087                 if ( $db->numRows( $res ) ) {
2088                         while ( $row = $db->fetchObject( $res ) ) {
2089                                 $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
2090                         }
2091                 }
2092                 $db->freeResult( $res );
2093                 return $retVal;
2094         }
2095
2096
2097         /**
2098          * Get a list of URLs to purge from the Squid cache when this
2099          * page changes
2100          *
2101          * @return array the URLs
2102          */
2103         public function getSquidURLs() {
2104                 global $wgContLang;
2105
2106                 $urls = array(
2107                         $this->getInternalURL(),
2108                         $this->getInternalURL( 'action=history' )
2109                 );
2110
2111                 // purge variant urls as well
2112                 if($wgContLang->hasVariants()){
2113                         $variants = $wgContLang->getVariants();
2114                         foreach($variants as $vCode){
2115                                 if($vCode==$wgContLang->getCode()) continue; // we don't want default variant
2116                                 $urls[] = $this->getInternalURL('',$vCode);
2117                         }
2118                 }
2119
2120                 return $urls;
2121         }
2122
2123         public function purgeSquid() {
2124                 global $wgUseSquid;
2125                 if ( $wgUseSquid ) {
2126                         $urls = $this->getSquidURLs();
2127                         $u = new SquidUpdate( $urls );
2128                         $u->doUpdate();
2129                 }
2130         }
2131
2132         /**
2133          * Move this page without authentication
2134          * @param Title &$nt the new page Title
2135          */
2136         public function moveNoAuth( &$nt ) {
2137                 return $this->moveTo( $nt, false );
2138         }
2139
2140         /**
2141          * Check whether a given move operation would be valid.
2142          * Returns true if ok, or a message key string for an error message
2143          * if invalid. (Scarrrrry ugly interface this.)
2144          * @param Title &$nt the new title
2145          * @param bool $auth indicates whether $wgUser's permissions
2146          *      should be checked
2147          * @return mixed true on success, message name on failure
2148          */
2149         public function isValidMoveOperation( &$nt, $auth = true ) {
2150                 if( !$this or !$nt ) {
2151                         return 'badtitletext';
2152                 }
2153                 if( $this->equals( $nt ) ) {
2154                         return 'selfmove';
2155                 }
2156                 if( !$this->isMovable() || !$nt->isMovable() ) {
2157                         return 'immobile_namespace';
2158                 }
2159
2160                 $oldid = $this->getArticleID();
2161                 $newid = $nt->getArticleID();
2162
2163                 if ( strlen( $nt->getDBkey() ) < 1 ) {
2164                         return 'articleexists';
2165                 }
2166                 if ( ( '' == $this->getDBkey() ) ||
2167                          ( !$oldid ) ||
2168                      ( '' == $nt->getDBkey() ) ) {
2169                         return 'badarticleerror';
2170                 }
2171
2172                 if ( $auth && (
2173                                 !$this->userCan( 'edit' ) || !$nt->userCan( 'edit' ) ||
2174                                 !$this->userCan( 'move' ) || !$nt->userCan( 'move' ) ) ) {
2175                         return 'protectedpage';
2176                 }
2177
2178                 # The move is allowed only if (1) the target doesn't exist, or
2179                 # (2) the target is a redirect to the source, and has no history
2180                 # (so we can undo bad moves right after they're done).
2181
2182                 if ( 0 != $newid ) { # Target exists; check for validity
2183                         if ( ! $this->isValidMoveTarget( $nt ) ) {
2184                                 return 'articleexists';
2185                         }
2186                 }
2187                 return true;
2188         }
2189
2190         /**
2191          * Move a title to a new location
2192          * @param Title &$nt the new title
2193          * @param bool $auth indicates whether $wgUser's permissions
2194          *      should be checked
2195          * @param string $reason The reason for the move
2196          * @param bool $createRedirect Whether to create a redirect from the old title to the new title
2197          * @return mixed true on success, message name on failure
2198          */
2199         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
2200                 $err = $this->isValidMoveOperation( $nt, $auth );
2201                 if( is_string( $err ) ) {
2202                         return $err;
2203                 }
2204
2205                 $pageid = $this->getArticleID();
2206                 if( $nt->exists() ) {
2207                         $this->moveOverExistingRedirect( $nt, $reason, $createRedirect );
2208                         $pageCountChange = ($createRedirect ? 0 : -1);
2209                 } else { # Target didn't exist, do normal move.
2210                         $this->moveToNewTitle( $nt, $reason, $createRedirect );
2211                         $pageCountChange = ($createRedirect ? 1 : 0);
2212                 }
2213                 $redirid = $this->getArticleID();
2214
2215                 # Fixing category links (those without piped 'alternate' names) to be sorted under the new title
2216                 $dbw = wfGetDB( DB_MASTER );
2217                 $categorylinks = $dbw->tableName( 'categorylinks' );
2218                 $sql = "UPDATE $categorylinks SET cl_sortkey=" . $dbw->addQuotes( $nt->getPrefixedText() ) .
2219                         " WHERE cl_from=" . $dbw->addQuotes( $pageid ) .
2220                         " AND cl_sortkey=" . $dbw->addQuotes( $this->getPrefixedText() );
2221                 $dbw->query( $sql, 'SpecialMovepage::doSubmit' );
2222
2223                 # Update watchlists
2224
2225                 $oldnamespace = $this->getNamespace() & ~1;
2226                 $newnamespace = $nt->getNamespace() & ~1;
2227                 $oldtitle = $this->getDBkey();
2228                 $newtitle = $nt->getDBkey();
2229
2230                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
2231                         WatchedItem::duplicateEntries( $this, $nt );
2232                 }
2233
2234                 # Update search engine
2235                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
2236                 $u->doUpdate();
2237                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
2238                 $u->doUpdate();
2239
2240                 # Update site_stats
2241                 if( $this->isContentPage() && !$nt->isContentPage() ) {
2242                         # No longer a content page
2243                         # Not viewed, edited, removing
2244                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange );
2245                 } elseif( !$this->isContentPage() && $nt->isContentPage() ) {
2246                         # Now a content page
2247                         # Not viewed, edited, adding
2248                         $u = new SiteStatsUpdate( 0, 1, +1, $pageCountChange );
2249                 } elseif( $pageCountChange ) {
2250                         # Redirect added
2251                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
2252                 } else {
2253                         # Nothing special
2254                         $u = false;
2255                 }
2256                 if( $u )
2257                         $u->doUpdate();
2258
2259                 global $wgUser;
2260                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
2261                 return true;
2262         }
2263
2264         /**
2265          * Move page to a title which is at present a redirect to the
2266          * source page
2267          *
2268          * @param Title &$nt the page to move to, which should currently
2269          *      be a redirect
2270          * @param string $reason The reason for the move
2271          * @param bool $createRedirect Whether to leave a redirect at the old title
2272          */
2273         private function moveOverExistingRedirect( &$nt, $reason = '', $createRedirect = true ) {
2274                 global $wgUseSquid;
2275                 $fname = 'Title::moveOverExistingRedirect';
2276                 $comment = wfMsgForContent( '1movedto2_redir', $this->getPrefixedText(), $nt->getPrefixedText() );
2277
2278                 if ( $reason ) {
2279                         $comment .= ": $reason";
2280                 }
2281
2282                 $now = wfTimestampNow();
2283                 $newid = $nt->getArticleID();
2284                 $oldid = $this->getArticleID();
2285                 $dbw = wfGetDB( DB_MASTER );
2286                 $linkCache =& LinkCache::singleton();
2287
2288                 # Delete the old redirect. We don't save it to history since
2289                 # by definition if we've got here it's rather uninteresting.
2290                 # We have to remove it so that the next step doesn't trigger
2291                 # a conflict on the unique namespace+title index...
2292                 $dbw->delete( 'page', array( 'page_id' => $newid ), $fname );
2293
2294                 # Save a null revision in the page's history notifying of the move
2295                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
2296                 $nullRevId = $nullRevision->insertOn( $dbw );
2297
2298                 # Change the name of the target page:
2299                 $dbw->update( 'page',
2300                         /* SET */ array(
2301                                 'page_touched'   => $dbw->timestamp($now),
2302                                 'page_namespace' => $nt->getNamespace(),
2303                                 'page_title'     => $nt->getDBkey(),
2304                                 'page_latest'    => $nullRevId,
2305                         ),
2306                         /* WHERE */ array( 'page_id' => $oldid ),
2307                         $fname
2308                 );
2309                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
2310
2311                 # Recreate the redirect, this time in the other direction.
2312                 if($createRedirect)
2313                 {
2314                         $mwRedir = MagicWord::get( 'redirect' );
2315                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
2316                         $redirectArticle = new Article( $this );
2317                         $newid = $redirectArticle->insertOn( $dbw );
2318                         $redirectRevision = new Revision( array(
2319                                 'page'    => $newid,
2320                                 'comment' => $comment,
2321                                 'text'    => $redirectText ) );
2322                         $redirectRevision->insertOn( $dbw );
2323                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
2324                         $linkCache->clearLink( $this->getPrefixedDBkey() );
2325
2326                         # Now, we record the link from the redirect to the new title.
2327                         # It should have no other outgoing links...
2328                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), $fname );
2329                         $dbw->insert( 'pagelinks',
2330                                 array(
2331                                         'pl_from'      => $newid,
2332                                         'pl_namespace' => $nt->getNamespace(),
2333                                         'pl_title'     => $nt->getDbKey() ),
2334                                 $fname );
2335                 }
2336
2337                 # Log the move
2338                 $log = new LogPage( 'move' );
2339                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText() ) );
2340
2341                 # Purge squid
2342                 if ( $wgUseSquid ) {
2343                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
2344                         $u = new SquidUpdate( $urls );
2345                         $u->doUpdate();
2346                 }
2347         }
2348
2349         /**
2350          * Move page to non-existing title.
2351          * @param Title &$nt the new Title
2352          * @param string $reason The reason for the move
2353          * @param bool $createRedirect Whether to create a redirect from the old title to the new title
2354          */
2355         private function moveToNewTitle( &$nt, $reason = '', $createRedirect = true ) {
2356                 global $wgUseSquid;
2357                 $fname = 'MovePageForm::moveToNewTitle';
2358                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
2359                 if ( $reason ) {
2360                         $comment .= ": $reason";
2361                 }
2362
2363                 $newid = $nt->getArticleID();
2364                 $oldid = $this->getArticleID();
2365                 $dbw = wfGetDB( DB_MASTER );
2366                 $now = $dbw->timestamp();
2367                 $linkCache =& LinkCache::singleton();
2368
2369                 # Save a null revision in the page's history notifying of the move
2370                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
2371                 $nullRevId = $nullRevision->insertOn( $dbw );
2372
2373                 # Rename cur entry
2374                 $dbw->update( 'page',
2375                         /* SET */ array(
2376                                 'page_touched'   => $now,
2377                                 'page_namespace' => $nt->getNamespace(),
2378                                 'page_title'     => $nt->getDBkey(),
2379                                 'page_latest'    => $nullRevId,
2380                         ),
2381                         /* WHERE */ array( 'page_id' => $oldid ),
2382                         $fname
2383                 );
2384
2385                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
2386
2387                 if($createRedirect)
2388                 {
2389                         # Insert redirect
2390                         $mwRedir = MagicWord::get( 'redirect' );
2391                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
2392                         $redirectArticle = new Article( $this );
2393                         $newid = $redirectArticle->insertOn( $dbw );
2394                         $redirectRevision = new Revision( array(
2395                                 'page'    => $newid,
2396                                 'comment' => $comment,
2397                                 'text'    => $redirectText ) );
2398                         $redirectRevision->insertOn( $dbw );
2399                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
2400                         $linkCache->clearLink( $this->getPrefixedDBkey() );
2401                         # Record the just-created redirect's linking to the page
2402                         $dbw->insert( 'pagelinks',
2403                                 array(
2404                                         'pl_from'      => $newid,
2405                                         'pl_namespace' => $nt->getNamespace(),
2406                                         'pl_title'     => $nt->getDBkey() ),
2407                                 $fname );
2408                 }
2409
2410                 # Log the move
2411                 $log = new LogPage( 'move' );
2412                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText()) );
2413
2414                 # Purge caches as per article creation
2415                 Article::onArticleCreate( $nt );
2416
2417                 # Purge old title from squid
2418                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
2419                 $this->purgeSquid();
2420         }
2421
2422         /**
2423          * Checks if $this can be moved to a given Title
2424          * - Selects for update, so don't call it unless you mean business
2425          *
2426          * @param Title &$nt the new title to check
2427          */
2428         public function isValidMoveTarget( $nt ) {
2429
2430                 $fname = 'Title::isValidMoveTarget';
2431                 $dbw = wfGetDB( DB_MASTER );
2432
2433                 # Is it a redirect?
2434                 $id  = $nt->getArticleID();
2435                 $obj = $dbw->selectRow( array( 'page', 'revision', 'text'),
2436                         array( 'page_is_redirect','old_text','old_flags' ),
2437                         array( 'page_id' => $id, 'page_latest=rev_id', 'rev_text_id=old_id' ),
2438                         $fname, 'FOR UPDATE' );
2439
2440                 if ( !$obj || 0 == $obj->page_is_redirect ) {
2441                         # Not a redirect
2442                         wfDebug( __METHOD__ . ": not a redirect\n" );
2443                         return false;
2444                 }
2445                 $text = Revision::getRevisionText( $obj );
2446
2447                 # Does the redirect point to the source?
2448                 # Or is it a broken self-redirect, usually caused by namespace collisions?
2449                 $m = array();
2450                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
2451                         $redirTitle = Title::newFromText( $m[1] );
2452                         if( !is_object( $redirTitle ) ||
2453                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
2454                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
2455                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
2456                                 return false;
2457                         }
2458                 } else {
2459                         # Fail safe
2460                         wfDebug( __METHOD__ . ": failsafe\n" );
2461                         return false;
2462                 }
2463
2464                 # Does the article have a history?
2465                 $row = $dbw->selectRow( array( 'page', 'revision'),
2466                         array( 'rev_id' ),
2467                         array( 'page_namespace' => $nt->getNamespace(),
2468                                 'page_title' => $nt->getDBkey(),
2469                                 'page_id=rev_page AND page_latest != rev_id'
2470                         ), $fname, 'FOR UPDATE'
2471                 );
2472
2473                 # Return true if there was no history
2474                 return $row === false;
2475         }
2476
2477         /**
2478          * Can this title be added to a user's watchlist?
2479          *
2480          * @return bool
2481          */
2482         public function isWatchable() {
2483                 return !$this->isExternal()
2484                         && Namespace::isWatchable( $this->getNamespace() );
2485         }
2486
2487         /**
2488          * Get categories to which this Title belongs and return an array of
2489          * categories' names.
2490          *
2491          * @return array an array of parents in the form:
2492          *      $parent => $currentarticle
2493          */
2494         public function getParentCategories() {
2495                 global $wgContLang;
2496
2497                 $titlekey = $this->getArticleId();
2498                 $dbr = wfGetDB( DB_SLAVE );
2499                 $categorylinks = $dbr->tableName( 'categorylinks' );
2500
2501                 # NEW SQL
2502                 $sql = "SELECT * FROM $categorylinks"
2503                      ." WHERE cl_from='$titlekey'"
2504                          ." AND cl_from <> '0'"
2505                          ." ORDER BY cl_sortkey";
2506
2507                 $res = $dbr->query ( $sql ) ;
2508
2509                 if($dbr->numRows($res) > 0) {
2510                         while ( $x = $dbr->fetchObject ( $res ) )
2511                                 //$data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to);
2512                                 $data[$wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to] = $this->getFullText();
2513                         $dbr->freeResult ( $res ) ;
2514                 } else {
2515                         $data = array();
2516                 }
2517                 return $data;
2518         }
2519
2520         /**
2521          * Get a tree of parent categories
2522          * @param array $children an array with the children in the keys, to check for circular refs
2523          * @return array
2524          */
2525         public function getParentCategoryTree( $children = array() ) {
2526                 $parents = $this->getParentCategories();
2527
2528                 if($parents != '') {
2529                         foreach($parents as $parent => $current) {
2530                                 if ( array_key_exists( $parent, $children ) ) {
2531                                         # Circular reference
2532                                         $stack[$parent] = array();
2533                                 } else {
2534                                         $nt = Title::newFromText($parent);
2535                                         if ( $nt ) {
2536                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array($parent => 1) );
2537                                         }
2538                                 }
2539                         }
2540                         return $stack;
2541                 } else {
2542                         return array();
2543                 }
2544         }
2545
2546
2547         /**
2548          * Get an associative array for selecting this title from
2549          * the "page" table
2550          *
2551          * @return array
2552          */
2553         public function pageCond() {
2554                 return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
2555         }
2556
2557         /**
2558          * Get the revision ID of the previous revision
2559          *
2560          * @param integer $revision  Revision ID. Get the revision that was before this one.
2561          * @return integer $oldrevision|false
2562          */
2563         public function getPreviousRevisionID( $revision ) {
2564                 $dbr = wfGetDB( DB_SLAVE );
2565                 return $dbr->selectField( 'revision', 'rev_id',
2566                         'rev_page=' . intval( $this->getArticleId() ) .
2567                         ' AND rev_id<' . intval( $revision ) . ' ORDER BY rev_id DESC' );
2568         }
2569
2570         /**
2571          * Get the revision ID of the next revision
2572          *
2573          * @param integer $revision  Revision ID. Get the revision that was after this one.
2574          * @return integer $oldrevision|false
2575          */
2576         public function getNextRevisionID( $revision ) {
2577                 $dbr = wfGetDB( DB_SLAVE );
2578                 return $dbr->selectField( 'revision', 'rev_id',
2579                         'rev_page=' . intval( $this->getArticleId() ) .
2580                         ' AND rev_id>' . intval( $revision ) . ' ORDER BY rev_id' );
2581         }
2582
2583         /**
2584          * Get the number of revisions between the given revision IDs.
2585          *
2586          * @param integer $old  Revision ID.
2587          * @param integer $new  Revision ID.
2588          * @return integer  Number of revisions between these IDs.
2589          */
2590         public function countRevisionsBetween( $old, $new ) {
2591                 $dbr = wfGetDB( DB_SLAVE );
2592                 return $dbr->selectField( 'revision', 'count(*)',
2593                         'rev_page = ' . intval( $this->getArticleId() ) .
2594                         ' AND rev_id > ' . intval( $old ) .
2595                         ' AND rev_id < ' . intval( $new ) );
2596         }
2597
2598         /**
2599          * Compare with another title.
2600          *
2601          * @param Title $title
2602          * @return bool
2603          */
2604         public function equals( $title ) {
2605                 // Note: === is necessary for proper matching of number-like titles.
2606                 return $this->getInterwiki() === $title->getInterwiki()
2607                         && $this->getNamespace() == $title->getNamespace()
2608                         && $this->getDbkey() === $title->getDbkey();
2609         }
2610
2611         /**
2612          * Return a string representation of this title
2613          *
2614          * @return string
2615          */
2616         public function __toString() {
2617                 return $this->getPrefixedText();
2618         }
2619
2620         /**
2621          * Check if page exists
2622          * @return bool
2623          */
2624         public function exists() {
2625                 return $this->getArticleId() != 0;
2626         }
2627
2628         /**
2629          * Do we know that this title definitely exists, or should we otherwise
2630          * consider that it exists?
2631          *
2632          * @return bool
2633          */
2634         public function isAlwaysKnown() {
2635                 return $this->isExternal()
2636                         || ( $this->mNamespace == NS_MAIN && $this->mDbkeyform == '' )
2637                         || ( $this->mNamespace == NS_MEDIAWIKI && wfMsgWeirdKey( $this->mDbkeyform ) );
2638         }
2639
2640         /**
2641          * Update page_touched timestamps and send squid purge messages for
2642          * pages linking to this title. May be sent to the job queue depending
2643          * on the number of links. Typically called on create and delete.
2644          */
2645         public function touchLinks() {
2646                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
2647                 $u->doUpdate();
2648
2649                 if ( $this->getNamespace() == NS_CATEGORY ) {
2650                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
2651                         $u->doUpdate();
2652                 }
2653         }
2654
2655         /**
2656          * Get the last touched timestamp
2657          */
2658         public function getTouched() {
2659                 $dbr = wfGetDB( DB_SLAVE );
2660                 $touched = $dbr->selectField( 'page', 'page_touched',
2661                         array(
2662                                 'page_namespace' => $this->getNamespace(),
2663                                 'page_title' => $this->getDBkey()
2664                         ), __METHOD__
2665                 );
2666                 return $touched;
2667         }
2668
2669         public function trackbackURL() {
2670                 global $wgTitle, $wgScriptPath, $wgServer;
2671
2672                 return "$wgServer$wgScriptPath/trackback.php?article="
2673                         . htmlspecialchars(urlencode($wgTitle->getPrefixedDBkey()));
2674         }
2675
2676         public function trackbackRDF() {
2677                 $url = htmlspecialchars($this->getFullURL());
2678                 $title = htmlspecialchars($this->getText());
2679                 $tburl = $this->trackbackURL();
2680
2681                 return "
2682 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
2683          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
2684          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
2685 <rdf:Description
2686    rdf:about=\"$url\"
2687    dc:identifier=\"$url\"
2688    dc:title=\"$title\"
2689    trackback:ping=\"$tburl\" />
2690 </rdf:RDF>";
2691         }
2692
2693         /**
2694          * Generate strings used for xml 'id' names in monobook tabs
2695          * @return string
2696          */
2697         public function getNamespaceKey() {
2698                 global $wgContLang;
2699                 switch ($this->getNamespace()) {
2700                         case NS_MAIN:
2701                         case NS_TALK:
2702                                 return 'nstab-main';
2703                         case NS_USER:
2704                         case NS_USER_TALK:
2705                                 return 'nstab-user';
2706                         case NS_MEDIA:
2707                                 return 'nstab-media';
2708                         case NS_SPECIAL:
2709                                 return 'nstab-special';
2710                         case NS_PROJECT:
2711                         case NS_PROJECT_TALK:
2712                                 return 'nstab-project';
2713                         case NS_IMAGE:
2714                         case NS_IMAGE_TALK:
2715                                 return 'nstab-image';
2716                         case NS_MEDIAWIKI:
2717                         case NS_MEDIAWIKI_TALK:
2718                                 return 'nstab-mediawiki';
2719                         case NS_TEMPLATE:
2720                         case NS_TEMPLATE_TALK:
2721                                 return 'nstab-template';
2722                         case NS_HELP:
2723                         case NS_HELP_TALK:
2724                                 return 'nstab-help';
2725                         case NS_CATEGORY:
2726                         case NS_CATEGORY_TALK:
2727                                 return 'nstab-category';
2728                         default:
2729                                 return 'nstab-' . $wgContLang->lc( $this->getSubjectNsText() );
2730                 }
2731         }
2732
2733         /**
2734          * Returns true if this title resolves to the named special page
2735          * @param string $name The special page name
2736          */
2737         public function isSpecial( $name ) {
2738                 if ( $this->getNamespace() == NS_SPECIAL ) {
2739                         list( $thisName, /* $subpage */ ) = SpecialPage::resolveAliasWithSubpage( $this->getDBkey() );
2740                         if ( $name == $thisName ) {
2741                                 return true;
2742                         }
2743                 }
2744                 return false;
2745         }
2746
2747         /**
2748          * If the Title refers to a special page alias which is not the local default,
2749          * returns a new Title which points to the local default. Otherwise, returns $this.
2750          */
2751         public function fixSpecialName() {
2752                 if ( $this->getNamespace() == NS_SPECIAL ) {
2753                         $canonicalName = SpecialPage::resolveAlias( $this->mDbkeyform );
2754                         if ( $canonicalName ) {
2755                                 $localName = SpecialPage::getLocalNameFor( $canonicalName );
2756                                 if ( $localName != $this->mDbkeyform ) {
2757                                         return Title::makeTitle( NS_SPECIAL, $localName );
2758                                 }
2759                         }
2760                 }
2761                 return $this;
2762         }
2763
2764         /**
2765          * Is this Title in a namespace which contains content?
2766          * In other words, is this a content page, for the purposes of calculating
2767          * statistics, etc?
2768          *
2769          * @return bool
2770          */
2771         public function isContentPage() {
2772                 return Namespace::isContent( $this->getNamespace() );
2773         }
2774
2775 }
2776
2777