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         var $mLength;              # The page length, 0 for special pages
  67         var $mRedirect;            # Is the article at this title a redirect?
  68         /**#@-*/
  69
  70
  71         /**
  72          * Constructor
  73          * @private
  74          */
  75         /* private */ function __construct() {
  76                 $this->mInterwiki = $this->mUrlform =
  77                 $this->mTextform = $this->mDbkeyform = '';
  78                 $this->mArticleID = -1;
  79                 $this->mNamespace = NS_MAIN;
  80                 $this->mRestrictionsLoaded = false;
  81                 $this->mRestrictions = array();
  82                 # Dont change the following, NS_MAIN is hardcoded in several place
  83                 # See bug #696
  84                 $this->mDefaultNamespace = NS_MAIN;
  85                 $this->mWatched = NULL;
  86                 $this->mLatestID = false;
  87                 $this->mOldRestrictions = false;
  88                 $this->mLength = -1;
  89                 $this->mRedirect = NULL;
  90         }
  91
  92         /**
  93          * Create a new Title from a prefixed DB key
  94          * @param string $key The database key, which has underscores
  95          *      instead of spaces, possibly including namespace and
  96          *      interwiki prefixes
  97          * @return Title the new object, or NULL on an error
  98          */
  99         public static function newFromDBkey( $key ) {
 100                 $t = new Title();
 101                 $t->mDbkeyform = $key;
 102                 if( $t->secureAndSplit() )
 103                         return $t;
 104                 else
 105                         return NULL;
 106         }
 107
 108         /**
 109          * Create a new Title from text, such as what one would
 110          * find in a link. Decodes any HTML entities in the text.
 111          *
 112          * @param string $text the link text; spaces, prefixes,
 113          *      and an initial ':' indicating the main namespace
 114          *      are accepted
 115          * @param int $defaultNamespace the namespace to use if
 116          *      none is specified by a prefix
 117          * @return Title the new object, or NULL on an error
 118          */
 119         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 120                 if( is_object( $text ) ) {
 121                         throw new MWException( 'Title::newFromText given an object' );
 122                 }
 123
 124                 /**
 125                  * Wiki pages often contain multiple links to the same page.
 126                  * Title normalization and parsing can become expensive on
 127                  * pages with many links, so we can save a little time by
 128                  * caching them.
 129                  *
 130                  * In theory these are value objects and won't get changed...
 131                  */
 132                 if( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 133                         return Title::$titleCache[$text];
 134                 }
 135
 136                 /**
 137                  * Convert things like &eacute; &#257; or &#x3017; into real text...
 138                  */
 139                 $filteredText = Sanitizer::decodeCharReferences( $text );
 140
 141                 $t = new Title();
 142                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 143                 $t->mDefaultNamespace = $defaultNamespace;
 144
 145                 static $cachedcount = 0 ;
 146                 if( $t->secureAndSplit() ) {
 147                         if( $defaultNamespace == NS_MAIN ) {
 148                                 if( $cachedcount >= MW_TITLECACHE_MAX ) {
 149                                         # Avoid memory leaks on mass operations...
 150                                         Title::$titleCache = array();
 151                                         $cachedcount=0;
 152                                 }
 153                                 $cachedcount++;
 154                                 Title::$titleCache[$text] =& $t;
 155                         }
 156                         return $t;
 157                 } else {
 158                         $ret = NULL;
 159                         return $ret;
 160                 }
 161         }
 162
 163         /**
 164          * Create a new Title from URL-encoded text. Ensures that
 165          * the given title's length does not exceed the maximum.
 166          * @param string $url the title, as might be taken from a URL
 167          * @return Title the new object, or NULL on an error
 168          */
 169         public static function newFromURL( $url ) {
 170                 global $wgLegalTitleChars;
 171                 $t = new Title();
 172
 173                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 174                 # but some URLs used it as a space replacement and they still come
 175                 # from some external search tools.
 176                 if ( strpos( $wgLegalTitleChars, '+' ) === false ) {
 177                         $url = str_replace( '+', ' ', $url );
 178                 }
 179
 180                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 181                 if( $t->secureAndSplit() ) {
 182                         return $t;
 183                 } else {
 184                         return NULL;
 185                 }
 186         }
 187
 188         /**
 189          * Create a new Title from an article ID
 190          *
 191          * @todo This is inefficiently implemented, the page row is requested
 192          *       but not used for anything else
 193          *
 194          * @param int $id the page_id corresponding to the Title to create
 195          * @return Title the new object, or NULL on an error
 196          */
 197         public static function newFromID( $id ) {
 198                 $fname = 'Title::newFromID';
 199                 $dbr = wfGetDB( DB_SLAVE );
 200                 $row = $dbr->selectRow( 'page', array( 'page_namespace', 'page_title' ),
 201                         array( 'page_id' => $id ), $fname );
 202                 if ( $row !== false ) {
 203                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 204                 } else {
 205                         $title = NULL;
 206                 }
 207                 return $title;
 208         }
 209
 210         /**
 211          * Make an array of titles from an array of IDs
 212          */
 213         public static function newFromIDs( $ids ) {
 214                 if ( !count( $ids ) ) {
 215                         return array();
 216                 }
 217                 $dbr = wfGetDB( DB_SLAVE );
 218                 $res = $dbr->select( 'page', array( 'page_namespace', 'page_title' ),
 219                         'page_id IN (' . $dbr->makeList( $ids ) . ')', __METHOD__ );
 220
 221                 $titles = array();
 222                 while ( $row = $dbr->fetchObject( $res ) ) {
 223                         $titles[] = Title::makeTitle( $row->page_namespace, $row->page_title );
 224                 }
 225                 return $titles;
 226         }
 227
 228         /**
 229          * Make a Title object from a DB row
 230          * @param Row $row (needs at least page_title,page_namespace)
 231          */
 232         public static function newFromRow( $row ) {
 233                 $t = self::makeTitle( $row->page_namespace, $row->page_title );
 234
 235                 $t->mArticleID = isset($row->page_id) ? intval($row->page_id) : -1;
 236                 $t->mLength = isset($row->page_len) ? intval($row->page_len) : -1;
 237                 $t->mRedirect = isset($row->page_is_redirect) ? (bool)$row->page_is_redirect : NULL;
 238                 $t->mLatestID = isset($row->page_latest) ? $row->page_latest : false;
 239
 240                 return $t;
 241         }
 242
 243         /**
 244          * Create a new Title from a namespace index and a DB key.
 245          * It's assumed that $ns and $title are *valid*, for instance when
 246          * they came directly from the database or a special page name.
 247          * For convenience, spaces are converted to underscores so that
 248          * eg user_text fields can be used directly.
 249          *
 250          * @param int $ns the namespace of the article
 251          * @param string $title the unprefixed database key form
 252          * @return Title the new object
 253          */
 254         public static function &makeTitle( $ns, $title ) {
 255                 $t = new Title();
 256                 $t->mInterwiki = '';
 257                 $t->mFragment = '';
 258                 $t->mNamespace = $ns = intval( $ns );
 259                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 260                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 261                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 262                 $t->mTextform = str_replace( '_', ' ', $title );
 263                 return $t;
 264         }
 265
 266         /**
 267          * Create a new Title from a namespace index and a DB key.
 268          * The parameters will be checked for validity, which is a bit slower
 269          * than makeTitle() but safer for user-provided data.
 270          *
 271          * @param int $ns the namespace of the article
 272          * @param string $title the database key form
 273          * @return Title the new object, or NULL on an error
 274          */
 275         public static function makeTitleSafe( $ns, $title ) {
 276                 $t = new Title();
 277                 $t->mDbkeyform = Title::makeName( $ns, $title );
 278                 if( $t->secureAndSplit() ) {
 279                         return $t;
 280                 } else {
 281                         return NULL;
 282                 }
 283         }
 284
 285         /**
 286          * Create a new Title for the Main Page
 287          * @return Title the new object
 288          */
 289         public static function newMainPage() {
 290                 $title = Title::newFromText( wfMsgForContent( 'mainpage' ) );
 291                 // Don't give fatal errors if the message is broken
 292                 if ( !$title ) {
 293                         $title = Title::newFromText( 'Main Page' );
 294                 }
 295                 return $title;
 296         }
 297
 298         /**
 299          * Extract a redirect destination from a string and return the
 300          * Title, or null if the text doesn't contain a valid redirect
 301          *
 302          * @param string $text Text with possible redirect
 303          * @return Title
 304          */
 305         public static function newFromRedirect( $text ) {
 306                 $redir = MagicWord::get( 'redirect' );
 307                 if( $redir->matchStart( trim($text) ) ) {
 308                         // Extract the first link and see if it's usable
 309                         $m = array();
 310                         if( preg_match( '!\[{2}(.*?)(?:\|.*?)?\]{2}!', $text, $m ) ) {
 311                                 // Strip preceding colon used to "escape" categories, etc.
 312                                 // and URL-decode links
 313                                 if( strpos( $m[1], '%' ) !== false ) {
 314                                         // Match behavior of inline link parsing here;
 315                                         // don't interpret + as " " most of the time!
 316                                         // It might be safe to just use rawurldecode instead, though.
 317                                         $m[1] = urldecode( ltrim( $m[1], ':' ) );
 318                                 }
 319                                 $title = Title::newFromText( $m[1] );
 320                                 // Redirects to Special:Userlogout are not permitted
 321                                 if( $title instanceof Title && !$title->isSpecial( 'Userlogout' ) )
 322                                         return $title;
 323                         }
 324                 }
 325                 return null;
 326         }
 327
 328 #----------------------------------------------------------------------------
 329 #       Static functions
 330 #----------------------------------------------------------------------------
 331
 332         /**
 333          * Get the prefixed DB key associated with an ID
 334          * @param int $id the page_id of the article
 335          * @return Title an object representing the article, or NULL
 336          *      if no such article was found
 337          * @static
 338          * @access public
 339          */
 340         function nameOf( $id ) {
 341                 $fname = 'Title::nameOf';
 342                 $dbr = wfGetDB( DB_SLAVE );
 343
 344                 $s = $dbr->selectRow( 'page', array( 'page_namespace','page_title' ),  array( 'page_id' => $id ), $fname );
 345                 if ( $s === false ) { return NULL; }
 346
 347                 $n = Title::makeName( $s->page_namespace, $s->page_title );
 348                 return $n;
 349         }
 350
 351         /**
 352          * Get a regex character class describing the legal characters in a link
 353          * @return string the list of characters, not delimited
 354          */
 355         public static function legalChars() {
 356                 global $wgLegalTitleChars;
 357                 return $wgLegalTitleChars;
 358         }
 359
 360         /**
 361          * Get a string representation of a title suitable for
 362          * including in a search index
 363          *
 364          * @param int $ns a namespace index
 365          * @param string $title text-form main part
 366          * @return string a stripped-down title string ready for the
 367          *      search index
 368          */
 369         public static function indexTitle( $ns, $title ) {
 370                 global $wgContLang;
 371
 372                 $lc = SearchEngine::legalSearchChars() . '&#;';
 373                 $t = $wgContLang->stripForSearch( $title );
 374                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 375                 $t = $wgContLang->lc( $t );
 376
 377                 # Handle 's, s'
 378                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 379                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 380
 381                 $t = preg_replace( "/\\s+/", ' ', $t );
 382
 383                 if ( $ns == NS_IMAGE ) {
 384                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 385                 }
 386                 return trim( $t );
 387         }
 388
 389         /*
 390          * Make a prefixed DB key from a DB key and a namespace index
 391          * @param int $ns numerical representation of the namespace
 392          * @param string $title the DB key form the title
 393          * @return string the prefixed form of the title
 394          */
 395         public static function makeName( $ns, $title ) {
 396                 global $wgContLang;
 397
 398                 $n = $wgContLang->getNsText( $ns );
 399                 return $n == '' ? $title : "$n:$title";
 400         }
 401
 402         /**
 403          * Returns the URL associated with an interwiki prefix
 404          * @param string $key the interwiki prefix (e.g. "MeatBall")
 405          * @return the associated URL, containing "$1", which should be
 406          *      replaced by an article title
 407          * @static (arguably)
 408          */
 409         public function getInterwikiLink( $key )  {
 410                 global $wgMemc, $wgInterwikiExpiry;
 411                 global $wgInterwikiCache, $wgContLang;
 412                 $fname = 'Title::getInterwikiLink';
 413
 414                 $key = $wgContLang->lc( $key );
 415
 416                 $k = wfMemcKey( 'interwiki', $key );
 417                 if( array_key_exists( $k, Title::$interwikiCache ) ) {
 418                         return Title::$interwikiCache[$k]->iw_url;
 419                 }
 420
 421                 if ($wgInterwikiCache) {
 422                         return Title::getInterwikiCached( $key );
 423                 }
 424
 425                 $s = $wgMemc->get( $k );
 426                 # Ignore old keys with no iw_local
 427                 if( $s && isset( $s->iw_local ) && isset($s->iw_trans)) {
 428                         Title::$interwikiCache[$k] = $s;
 429                         return $s->iw_url;
 430                 }
 431
 432                 $dbr = wfGetDB( DB_SLAVE );
 433                 $res = $dbr->select( 'interwiki',
 434                         array( 'iw_url', 'iw_local', 'iw_trans' ),
 435                         array( 'iw_prefix' => $key ), $fname );
 436                 if( !$res ) {
 437                         return '';
 438                 }
 439
 440                 $s = $dbr->fetchObject( $res );
 441                 if( !$s ) {
 442                         # Cache non-existence: create a blank object and save it to memcached
 443                         $s = (object)false;
 444                         $s->iw_url = '';
 445                         $s->iw_local = 0;
 446                         $s->iw_trans = 0;
 447                 }
 448                 $wgMemc->set( $k, $s, $wgInterwikiExpiry );
 449                 Title::$interwikiCache[$k] = $s;
 450
 451                 return $s->iw_url;
 452         }
 453
 454         /**
 455          * Fetch interwiki prefix data from local cache in constant database
 456          *
 457          * More logic is explained in DefaultSettings
 458          *
 459          * @return string URL of interwiki site
 460          */
 461         public static function getInterwikiCached( $key ) {
 462                 global $wgInterwikiCache, $wgInterwikiScopes, $wgInterwikiFallbackSite;
 463                 static $db, $site;
 464
 465                 if (!$db)
 466                         $db=dba_open($wgInterwikiCache,'r','cdb');
 467                 /* Resolve site name */
 468                 if ($wgInterwikiScopes>=3 and !$site) {
 469                         $site = dba_fetch('__sites:' . wfWikiID(), $db);
 470                         if ($site=="")
 471                                 $site = $wgInterwikiFallbackSite;
 472                 }
 473                 $value = dba_fetch( wfMemcKey( $key ), $db);
 474                 if ($value=='' and $wgInterwikiScopes>=3) {
 475                         /* try site-level */
 476                         $value = dba_fetch("_{$site}:{$key}", $db);
 477                 }
 478                 if ($value=='' and $wgInterwikiScopes>=2) {
 479                         /* try globals */
 480                         $value = dba_fetch("__global:{$key}", $db);
 481                 }
 482                 if ($value=='undef')
 483                         $value='';
 484                 $s = (object)false;
 485                 $s->iw_url = '';
 486                 $s->iw_local = 0;
 487                 $s->iw_trans = 0;
 488                 if ($value!='') {
 489                         list($local,$url)=explode(' ',$value,2);
 490                         $s->iw_url=$url;
 491                         $s->iw_local=(int)$local;
 492                 }
 493                 Title::$interwikiCache[wfMemcKey( 'interwiki', $key )] = $s;
 494                 return $s->iw_url;
 495         }
 496         /**
 497          * Determine whether the object refers to a page within
 498          * this project.
 499          *
 500          * @return bool TRUE if this is an in-project interwiki link
 501          *      or a wikilink, FALSE otherwise
 502          */
 503         public function isLocal() {
 504                 if ( $this->mInterwiki != '' ) {
 505                         # Make sure key is loaded into cache
 506                         $this->getInterwikiLink( $this->mInterwiki );
 507                         $k = wfMemcKey( 'interwiki', $this->mInterwiki );
 508                         return (bool)(Title::$interwikiCache[$k]->iw_local);
 509                 } else {
 510                         return true;
 511                 }
 512         }
 513
 514         /**
 515          * Determine whether the object refers to a page within
 516          * this project and is transcludable.
 517          *
 518          * @return bool TRUE if this is transcludable
 519          */
 520         public function isTrans() {
 521                 if ($this->mInterwiki == '')
 522                         return false;
 523                 # Make sure key is loaded into cache
 524                 $this->getInterwikiLink( $this->mInterwiki );
 525                 $k = wfMemcKey( 'interwiki', $this->mInterwiki );
 526                 return (bool)(Title::$interwikiCache[$k]->iw_trans);
 527         }
 528
 529         /**
 530          * Escape a text fragment, say from a link, for a URL
 531          */
 532         static function escapeFragmentForURL( $fragment ) {
 533                 $fragment = str_replace( ' ', '_', $fragment );
 534                 $fragment = urlencode( Sanitizer::decodeCharReferences( $fragment ) );
 535                 $replaceArray = array(
 536                         '%3A' => ':',
 537                         '%' => '.'
 538                 );
 539                 return strtr( $fragment, $replaceArray );
 540         }
 541
 542 #----------------------------------------------------------------------------
 543 #       Other stuff
 544 #----------------------------------------------------------------------------
 545
 546         /** Simple accessors */
 547         /**
 548          * Get the text form (spaces not underscores) of the main part
 549          * @return string
 550          */
 551         public function getText() { return $this->mTextform; }
 552         /**
 553          * Get the URL-encoded form of the main part
 554          * @return string
 555          */
 556         public function getPartialURL() { return $this->mUrlform; }
 557         /**
 558          * Get the main part with underscores
 559          * @return string
 560          */
 561         public function getDBkey() { return $this->mDbkeyform; }
 562         /**
 563          * Get the namespace index, i.e. one of the NS_xxxx constants
 564          * @return int
 565          */
 566         public function getNamespace() { return $this->mNamespace; }
 567         /**
 568          * Get the namespace text
 569          * @return string
 570          */
 571         public function getNsText() {
 572                 global $wgContLang, $wgCanonicalNamespaceNames;
 573
 574                 if ( '' != $this->mInterwiki ) {
 575                         // This probably shouldn't even happen. ohh man, oh yuck.
 576                         // But for interwiki transclusion it sometimes does.
 577                         // Shit. Shit shit shit.
 578                         //
 579                         // Use the canonical namespaces if possible to try to
 580                         // resolve a foreign namespace.
 581                         if( isset( $wgCanonicalNamespaceNames[$this->mNamespace] ) ) {
 582                                 return $wgCanonicalNamespaceNames[$this->mNamespace];
 583                         }
 584                 }
 585                 return $wgContLang->getNsText( $this->mNamespace );
 586         }
 587         /**
 588          * Get the DB key with the initial letter case as specified by the user
 589          */
 590         function getUserCaseDBKey() {
 591                 return $this->mUserCaseDBKey;
 592         }
 593         /**
 594          * Get the namespace text of the subject (rather than talk) page
 595          * @return string
 596          */
 597         public function getSubjectNsText() {
 598                 global $wgContLang;
 599                 return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
 600         }
 601
 602         /**
 603          * Get the namespace text of the talk page
 604          * @return string
 605          */
 606         public function getTalkNsText() {
 607                 global $wgContLang;
 608                 return( $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) ) );
 609         }
 610
 611         /**
 612          * Could this title have a corresponding talk page?
 613          * @return bool
 614          */
 615         public function canTalk() {
 616                 return( MWNamespace::canTalk( $this->mNamespace ) );
 617         }
 618
 619         /**
 620          * Get the interwiki prefix (or null string)
 621          * @return string
 622          */
 623         public function getInterwiki() { return $this->mInterwiki; }
 624         /**
 625          * Get the Title fragment (i.e. the bit after the #) in text form
 626          * @return string
 627          */
 628         public function getFragment() { return $this->mFragment; }
 629         /**
 630          * Get the fragment in URL form, including the "#" character if there is one
 631          * @return string
 632          */
 633         public function getFragmentForURL() {
 634                 if ( $this->mFragment == '' ) {
 635                         return '';
 636                 } else {
 637                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
 638                 }
 639         }
 640         /**
 641          * Get the default namespace index, for when there is no namespace
 642          * @return int
 643          */
 644         public function getDefaultNamespace() { return $this->mDefaultNamespace; }
 645
 646         /**
 647          * Get title for search index
 648          * @return string a stripped-down title string ready for the
 649          *      search index
 650          */
 651         public function getIndexTitle() {
 652                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 653         }
 654
 655         /**
 656          * Get the prefixed database key form
 657          * @return string the prefixed title, with underscores and
 658          *      any interwiki and namespace prefixes
 659          */
 660         public function getPrefixedDBkey() {
 661                 $s = $this->prefix( $this->mDbkeyform );
 662                 $s = str_replace( ' ', '_', $s );
 663                 return $s;
 664         }
 665
 666         /**
 667          * Get the prefixed title with spaces.
 668          * This is the form usually used for display
 669          * @return string the prefixed title, with spaces
 670          */
 671         public function getPrefixedText() {
 672                 if ( empty( $this->mPrefixedText ) ) { // FIXME: bad usage of empty() ?
 673                         $s = $this->prefix( $this->mTextform );
 674                         $s = str_replace( '_', ' ', $s );
 675                         $this->mPrefixedText = $s;
 676                 }
 677                 return $this->mPrefixedText;
 678         }
 679
 680         /**
 681          * Get the prefixed title with spaces, plus any fragment
 682          * (part beginning with '#')
 683          * @return string the prefixed title, with spaces and
 684          *      the fragment, including '#'
 685          */
 686         public function getFullText() {
 687                 $text = $this->getPrefixedText();
 688                 if( '' != $this->mFragment ) {
 689                         $text .= '#' . $this->mFragment;
 690                 }
 691                 return $text;
 692         }
 693
 694         /**
 695          * Get the base name, i.e. the leftmost parts before the /
 696          * @return string Base name
 697          */
 698         public function getBaseText() {
 699                 global $wgNamespacesWithSubpages;
 700                 if( !empty( $wgNamespacesWithSubpages[$this->mNamespace] ) ) {
 701                         $parts = explode( '/', $this->getText() );
 702                         # Don't discard the real title if there's no subpage involved
 703                         if( count( $parts ) > 1 )
 704                                 unset( $parts[ count( $parts ) - 1 ] );
 705                         return implode( '/', $parts );
 706                 } else {
 707                         return $this->getText();
 708                 }
 709         }
 710
 711         /**
 712          * Get the lowest-level subpage name, i.e. the rightmost part after /
 713          * @return string Subpage name
 714          */
 715         public function getSubpageText() {
 716                 global $wgNamespacesWithSubpages;
 717                 if( isset( $wgNamespacesWithSubpages[ $this->mNamespace ] ) && $wgNamespacesWithSubpages[ $this->mNamespace ] ) {
 718                         $parts = explode( '/', $this->mTextform );
 719                         return( $parts[ count( $parts ) - 1 ] );
 720                 } else {
 721                         return( $this->mTextform );
 722                 }
 723         }
 724
 725         /**
 726          * Get a URL-encoded form of the subpage text
 727          * @return string URL-encoded subpage name
 728          */
 729         public function getSubpageUrlForm() {
 730                 $text = $this->getSubpageText();
 731                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
 732                 $text = str_replace( '%28', '(', str_replace( '%29', ')', $text ) ); # Clean up the URL; per below, this might not be safe
 733                 return( $text );
 734         }
 735
 736         /**
 737          * Get a URL-encoded title (not an actual URL) including interwiki
 738          * @return string the URL-encoded form
 739          */
 740         public function getPrefixedURL() {
 741                 $s = $this->prefix( $this->mDbkeyform );
 742                 $s = str_replace( ' ', '_', $s );
 743
 744                 $s = wfUrlencode ( $s ) ;
 745
 746                 # Cleaning up URL to make it look nice -- is this safe?
 747                 $s = str_replace( '%28', '(', $s );
 748                 $s = str_replace( '%29', ')', $s );
 749
 750                 return $s;
 751         }
 752
 753         /**
 754          * Get a real URL referring to this title, with interwiki link and
 755          * fragment
 756          *
 757          * @param string $query an optional query string, not used
 758          *      for interwiki links
 759          * @param string $variant language variant of url (for sr, zh..)
 760          * @return string the URL
 761          */
 762         public function getFullURL( $query = '', $variant = false ) {
 763                 global $wgContLang, $wgServer, $wgRequest;
 764
 765                 if ( '' == $this->mInterwiki ) {
 766                         $url = $this->getLocalUrl( $query, $variant );
 767
 768                         // Ugly quick hack to avoid duplicate prefixes (bug 4571 etc)
 769                         // Correct fix would be to move the prepending elsewhere.
 770                         if ($wgRequest->getVal('action') != 'render') {
 771                                 $url = $wgServer . $url;
 772                         }
 773                 } else {
 774                         $baseUrl = $this->getInterwikiLink( $this->mInterwiki );
 775
 776                         $namespace = wfUrlencode( $this->getNsText() );
 777                         if ( '' != $namespace ) {
 778                                 # Can this actually happen? Interwikis shouldn't be parsed.
 779                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
 780                                 $namespace .= ':';
 781                         }
 782                         $url = str_replace( '$1', $namespace . $this->mUrlform, $baseUrl );
 783                         $url = wfAppendQuery( $url, $query );
 784                 }
 785
 786                 # Finally, add the fragment.
 787                 $url .= $this->getFragmentForURL();
 788
 789                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
 790                 return $url;
 791         }
 792
 793         /**
 794          * Get a URL with no fragment or server name.  If this page is generated
 795          * with action=render, $wgServer is prepended.
 796          * @param string $query an optional query string; if not specified,
 797          *      $wgArticlePath will be used.
 798          * @param string $variant language variant of url (for sr, zh..)
 799          * @return string the URL
 800          */
 801         public function getLocalURL( $query = '', $variant = false ) {
 802                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
 803                 global $wgVariantArticlePath, $wgContLang, $wgUser;
 804
 805                 // internal links should point to same variant as current page (only anonymous users)
 806                 if($variant == false && $wgContLang->hasVariants() && !$wgUser->isLoggedIn()){
 807                         $pref = $wgContLang->getPreferredVariant(false);
 808                         if($pref != $wgContLang->getCode())
 809                                 $variant = $pref;
 810                 }
 811
 812                 if ( $this->isExternal() ) {
 813                         $url = $this->getFullURL();
 814                         if ( $query ) {
 815                                 // This is currently only used for edit section links in the
 816                                 // context of interwiki transclusion. In theory we should
 817                                 // append the query to the end of any existing query string,
 818                                 // but interwiki transclusion is already broken in that case.
 819                                 $url .= "?$query";
 820                         }
 821                 } else {
 822                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 823                         if ( $query == '' ) {
 824                                 if( $variant != false && $wgContLang->hasVariants() ) {
 825                                         if( $wgVariantArticlePath == false ) {
 826                                                 $variantArticlePath =  "$wgScript?title=$1&variant=$2"; // default
 827                                         } else {
 828                                                 $variantArticlePath = $wgVariantArticlePath;
 829                                         }
 830                                         $url = str_replace( '$2', urlencode( $variant ), $variantArticlePath );
 831                                         $url = str_replace( '$1', $dbkey, $url  );
 832                                 } else {
 833                                         $url = str_replace( '$1', $dbkey, $wgArticlePath );
 834                                 }
 835                         } else {
 836                                 global $wgActionPaths;
 837                                 $url = false;
 838                                 $matches = array();
 839                                 if( !empty( $wgActionPaths ) &&
 840                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
 841                                 {
 842                                         $action = urldecode( $matches[2] );
 843                                         if( isset( $wgActionPaths[$action] ) ) {
 844                                                 $query = $matches[1];
 845                                                 if( isset( $matches[4] ) ) $query .= $matches[4];
 846                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
 847                                                 if( $query != '' ) $url .= '?' . $query;
 848                                         }
 849                                 }
 850                                 if ( $url === false ) {
 851                                         if ( $query == '-' ) {
 852                                                 $query = '';
 853                                         }
 854                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
 855                                 }
 856                         }
 857
 858                         // FIXME: this causes breakage in various places when we
 859                         // actually expected a local URL and end up with dupe prefixes.
 860                         if ($wgRequest->getVal('action') == 'render') {
 861                                 $url = $wgServer . $url;
 862                         }
 863                 }
 864                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
 865                 return $url;
 866         }
 867
 868         /**
 869          * Get an HTML-escaped version of the URL form, suitable for
 870          * using in a link, without a server name or fragment
 871          * @param string $query an optional query string
 872          * @return string the URL
 873          */
 874         public function escapeLocalURL( $query = '' ) {
 875                 return htmlspecialchars( $this->getLocalURL( $query ) );
 876         }
 877
 878         /**
 879          * Get an HTML-escaped version of the URL form, suitable for
 880          * using in a link, including the server name and fragment
 881          *
 882          * @return string the URL
 883          * @param string $query an optional query string
 884          */
 885         public function escapeFullURL( $query = '' ) {
 886                 return htmlspecialchars( $this->getFullURL( $query ) );
 887         }
 888
 889         /**
 890          * Get the URL form for an internal link.
 891          * - Used in various Squid-related code, in case we have a different
 892          * internal hostname for the server from the exposed one.
 893          *
 894          * @param string $query an optional query string
 895          * @param string $variant language variant of url (for sr, zh..)
 896          * @return string the URL
 897          */
 898         public function getInternalURL( $query = '', $variant = false ) {
 899                 global $wgInternalServer;
 900                 $url = $wgInternalServer . $this->getLocalURL( $query, $variant );
 901                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
 902                 return $url;
 903         }
 904
 905         /**
 906          * Get the edit URL for this Title
 907          * @return string the URL, or a null string if this is an
 908          *      interwiki link
 909          */
 910         public function getEditURL() {
 911                 if ( '' != $this->mInterwiki ) { return ''; }
 912                 $s = $this->getLocalURL( 'action=edit' );
 913
 914                 return $s;
 915         }
 916
 917         /**
 918          * Get the HTML-escaped displayable text form.
 919          * Used for the title field in <a> tags.
 920          * @return string the text, including any prefixes
 921          */
 922         public function getEscapedText() {
 923                 return htmlspecialchars( $this->getPrefixedText() );
 924         }
 925
 926         /**
 927          * Is this Title interwiki?
 928          * @return boolean
 929          */
 930         public function isExternal() { return ( '' != $this->mInterwiki ); }
 931
 932         /**
 933          * Is this page "semi-protected" - the *only* protection is autoconfirm?
 934          *
 935          * @param string Action to check (default: edit)
 936          * @return bool
 937          */
 938         public function isSemiProtected( $action = 'edit' ) {
 939                 if( $this->exists() ) {
 940                         $restrictions = $this->getRestrictions( $action );
 941                         if( count( $restrictions ) > 0 ) {
 942                                 foreach( $restrictions as $restriction ) {
 943                                         if( strtolower( $restriction ) != 'autoconfirmed' )
 944                                                 return false;
 945                                 }
 946                         } else {
 947                                 # Not protected
 948                                 return false;
 949                         }
 950                         return true;
 951                 } else {
 952                         # If it doesn't exist, it can't be protected
 953                         return false;
 954                 }
 955         }
 956
 957         /**
 958          * Does the title correspond to a protected article?
 959          * @param string $what the action the page is protected from,
 960          * by default checks move and edit
 961          * @return boolean
 962          */
 963         public function isProtected( $action = '' ) {
 964                 global $wgRestrictionLevels, $wgRestrictionTypes;
 965
 966                 # Special pages have inherent protection
 967                 if( $this->getNamespace() == NS_SPECIAL )
 968                         return true;
 969
 970                 # Check regular protection levels
 971                 foreach( $wgRestrictionTypes as $type ){
 972                         if( $action == $type || $action == '' ) {
 973                                 $r = $this->getRestrictions( $type );
 974                                 foreach( $wgRestrictionLevels as $level ) {
 975                                         if( in_array( $level, $r ) && $level != '' ) {
 976                                                 return true;
 977                                         }
 978                                 }
 979                         }
 980                 }
 981
 982                 return false;
 983         }
 984
 985         /**
 986          * Is $wgUser watching this page?
 987          * @return boolean
 988          */
 989         public function userIsWatching() {
 990                 global $wgUser;
 991
 992                 if ( is_null( $this->mWatched ) ) {
 993                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn()) {
 994                                 $this->mWatched = false;
 995                         } else {
 996                                 $this->mWatched = $wgUser->isWatched( $this );
 997                         }
 998                 }
 999                 return $this->mWatched;
1000         }
1001
1002         /**
1003          * Can $wgUser perform $action on this page?
1004          * This skips potentially expensive cascading permission checks.
1005          *
1006          * Suitable for use for nonessential UI controls in common cases, but
1007          * _not_ for functional access control.
1008          *
1009          * May provide false positives, but should never provide a false negative.
1010          *
1011          * @param string $action action that permission needs to be checked for
1012          * @return boolean
1013          */
1014         public function quickUserCan( $action ) {
1015                 return $this->userCan( $action, false );
1016         }
1017
1018         /**
1019          * Determines if $wgUser is unable to edit this page because it has been protected
1020          * by $wgNamespaceProtection.
1021          *
1022          * @return boolean
1023          */
1024         public function isNamespaceProtected() {
1025                 global $wgNamespaceProtection, $wgUser;
1026                 if( isset( $wgNamespaceProtection[ $this->mNamespace ] ) ) {
1027                         foreach( (array)$wgNamespaceProtection[ $this->mNamespace ] as $right ) {
1028                                 if( $right != '' && !$wgUser->isAllowed( $right ) )
1029                                         return true;
1030                         }
1031                 }
1032                 return false;
1033         }
1034
1035         /**
1036          * Can $wgUser perform $action on this page?
1037          * @param string $action action that permission needs to be checked for
1038          * @param bool $doExpensiveQueries Set this to false to avoid doing unnecessary queries.
1039          * @return boolean
1040          */
1041         public function userCan( $action, $doExpensiveQueries = true ) {
1042                 global $wgUser;
1043                 return ( $this->getUserPermissionsErrorsInternal( $action, $wgUser, $doExpensiveQueries ) === array());
1044         }
1045
1046         /**
1047          * Can $user perform $action on this page?
1048          *
1049          * FIXME: This *does not* check throttles (User::pingLimiter()).
1050          *
1051          * @param string $action action that permission needs to be checked for
1052          * @param User $user user to check
1053          * @param bool $doExpensiveQueries Set this to false to avoid doing unnecessary queries.
1054          * @return array Array of arrays of the arguments to wfMsg to explain permissions problems.
1055          */
1056         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true ) {
1057                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1058
1059                 global $wgContLang;
1060                 global $wgLang;
1061                 global $wgEmailConfirmToEdit;
1062
1063                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() ) {
1064                         $errors[] = array( 'confirmedittext' );
1065                 }
1066
1067                 if ( $user->isBlockedFrom( $this ) ) {
1068                         $block = $user->mBlock;
1069
1070                         // This is from OutputPage::blockedPage
1071                         // Copied at r23888 by werdna
1072
1073                         $id = $user->blockedBy();
1074                         $reason = $user->blockedFor();
1075                         if( $reason == '' ) {
1076                                 $reason = wfMsg( 'blockednoreason' );
1077                         }
1078                         $ip = wfGetIP();
1079
1080                         if ( is_numeric( $id ) ) {
1081                                 $name = User::whoIs( $id );
1082                         } else {
1083                                 $name = $id;
1084                         }
1085
1086                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1087                         $blockid = $block->mId;
1088                         $blockExpiry = $user->mBlock->mExpiry;
1089                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $user->mBlock->mTimestamp ), true );
1090
1091                         if ( $blockExpiry == 'infinity' ) {
1092                                 // Entry in database (table ipblocks) is 'infinity' but 'ipboptions' uses 'infinite' or 'indefinite'
1093                                 $scBlockExpiryOptions = wfMsg( 'ipboptions' );
1094
1095                                 foreach ( explode( ',', $scBlockExpiryOptions ) as $option ) {
1096                                         if ( strpos( $option, ':' ) == false )
1097                                                 continue;
1098
1099                                         list ($show, $value) = explode( ":", $option );
1100
1101                                         if ( $value == 'infinite' || $value == 'indefinite' ) {
1102                                                 $blockExpiry = $show;
1103                                                 break;
1104                                         }
1105                                 }
1106                         } else {
1107                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1108                         }
1109
1110                         $intended = $user->mBlock->mAddress;
1111
1112                         $errors[] = array ( ($block->mAuto ? 'autoblockedtext' : 'blockedtext'), $link, $reason, $ip, $name, $blockid, $blockExpiry, $intended, $blockTimestamp );
1113                 }
1114
1115                 return $errors;
1116         }
1117
1118         /**
1119          * Can $user perform $action on this page? This is an internal function,
1120          * which checks ONLY that previously checked by userCan (i.e. it leaves out
1121          * checks on wfReadOnly() and blocks)
1122          *
1123          * @param string $action action that permission needs to be checked for
1124          * @param User $user user to check
1125          * @param bool $doExpensiveQueries Set this to false to avoid doing unnecessary queries.
1126          * @return array Array of arrays of the arguments to wfMsg to explain permissions problems.
1127          */
1128         private function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true ) {
1129                 wfProfileIn( __METHOD__ );
1130
1131                 $errors = array();
1132
1133                 // Use getUserPermissionsErrors instead
1134                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1135                         return $result ? array() : array( array( 'badaccess-group0' ) );
1136                 }
1137
1138                 if (!wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1139                         if ($result != array() && is_array($result) && !is_array($result[0]))
1140                                 $errors[] = $result; # A single array representing an error
1141                         else if (is_array($result) && is_array($result[0]))
1142                                 $errors = array_merge( $errors, $result ); # A nested array representing multiple errors
1143                         else if ($result != '' && $result != null && $result !== true && $result !== false)
1144                                 $errors[] = array($result); # A string representing a message-id
1145                         else if ($result === false )
1146                                 $errors[] = array('badaccess-group0'); # a generic "We don't want them to do that"
1147                 }
1148                 if ($doExpensiveQueries && !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) ) ) {
1149                         if ($result != array() && is_array($result) && !is_array($result[0]))
1150                                 $errors[] = $result; # A single array representing an error
1151                         else if (is_array($result) && is_array($result[0]))
1152                                 $errors = array_merge( $errors, $result ); # A nested array representing multiple errors
1153                         else if ($result != '' && $result != null && $result !== true && $result !== false)
1154                                 $errors[] = array($result); # A string representing a message-id
1155                         else if ($result === false )
1156                                 $errors[] = array('badaccess-group0'); # a generic "We don't want them to do that"
1157                 }
1158
1159                 if( NS_SPECIAL == $this->mNamespace ) {
1160                         $errors[] = array('ns-specialprotected');
1161                 }
1162
1163                 if ( $this->isNamespaceProtected() ) {
1164                         $ns = $this->getNamespace() == NS_MAIN
1165                                 ? wfMsg( 'nstab-main' )
1166                                 : $this->getNsText();
1167                         $errors[] = (NS_MEDIAWIKI == $this->mNamespace
1168                                 ? array('protectedinterface')
1169                                 : array( 'namespaceprotected',  $ns ) );
1170                 }
1171
1172                 if( $this->mDbkeyform == '_' ) {
1173                         # FIXME: Is this necessary? Shouldn't be allowed anyway...
1174                         $errors[] = array('badaccess-group0');
1175                 }
1176
1177                 # protect css/js subpages of user pages
1178                 # XXX: this might be better using restrictions
1179                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssJsSubpage() from working
1180                 if( $this->isCssJsSubpage()
1181                         && !$user->isAllowed('editusercssjs')
1182                         && !preg_match('/^'.preg_quote($user->getName(), '/').'\//', $this->mTextform) ) {
1183                         $errors[] = array('customcssjsprotected');
1184                 }
1185
1186                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1187                         # We /could/ use the protection level on the source page, but it's fairly ugly
1188                         #  as we have to establish a precedence hierarchy for pages included by multiple
1189                         #  cascade-protected pages. So just restrict it to people with 'protect' permission,
1190                         #  as they could remove the protection anyway.
1191                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1192                         # Cascading protection depends on more than this page...
1193                         # Several cascading protected pages may include this page...
1194                         # Check each cascading level
1195                         # This is only for protection restrictions, not for all actions
1196                         if( $cascadingSources > 0 && isset($restrictions[$action]) ) {
1197                                 foreach( $restrictions[$action] as $right ) {
1198                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1199                                         if( '' != $right && !$user->isAllowed( $right ) ) {
1200                                                 $pages = '';
1201                                                 foreach( $cascadingSources as $page )
1202                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1203                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1204                                         }
1205                                 }
1206                         }
1207                 }
1208
1209                 foreach( $this->getRestrictions($action) as $right ) {
1210                         // Backwards compatibility, rewrite sysop -> protect
1211                         if ( $right == 'sysop' ) {
1212                                 $right = 'protect';
1213                         }
1214                         if( '' != $right && !$user->isAllowed( $right ) ) {
1215                                 //Users with 'editprotected' permission can edit protected pages
1216                                 if( $action=='edit' && $user->isAllowed( 'editprotected' ) ) {
1217                                         //Users with 'editprotected' permission cannot edit protected pages
1218                                         //with cascading option turned on.
1219                                         if($this->mCascadeRestriction) {
1220                                                 $errors[] = array( 'protectedpagetext', $right );
1221                                         } else {
1222                                                 //Nothing, user can edit!
1223                                         }
1224                                 } else {
1225                                         $errors[] = array( 'protectedpagetext', $right );
1226                                 }
1227                         }
1228                 }
1229
1230                 if ($action == 'protect') {
1231                         if ($this->getUserPermissionsErrors('edit', $user) != array()) {
1232                                 $errors[] = array( 'protect-cantedit' ); // If they can't edit, they shouldn't protect.
1233                         }
1234                 }
1235
1236                 if ($action == 'create') {
1237                         $title_protection = $this->getTitleProtection();
1238
1239                         if (is_array($title_protection)) {
1240                                 extract($title_protection);
1241
1242                                 if ($pt_create_perm == 'sysop')
1243                                         $pt_create_perm = 'protect';
1244
1245                                 if ($pt_create_perm == '' || !$user->isAllowed($pt_create_perm)) {
1246                                         $errors[] = array ( 'titleprotected', User::whoIs($pt_user), $pt_reason );
1247                                 }
1248                         }
1249
1250                         if( (  $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1251                                 ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1252                                 $errors[] = $user->isAnon() ? array ('nocreatetext') : array ('nocreate-loggedin');
1253                         }
1254                 } elseif( $action == 'move' && !( $this->isMovable() && $user->isAllowed( 'move' ) ) ) {
1255                         $errors[] = $user->isAnon() ? array ( 'movenologintext' ) : array ('movenotallowed');
1256                 } elseif ( !$user->isAllowed( $action ) ) {
1257                         $return = null;
1258                         $groups = array();
1259                         global $wgGroupPermissions;
1260                         foreach( $wgGroupPermissions as $key => $value ) {
1261                                 if( isset( $value[$action] ) && $value[$action] == true ) {
1262                                         $groupName = User::getGroupName( $key );
1263                                         $groupPage = User::getGroupPage( $key );
1264                                         if( $groupPage ) {
1265                                                 $groups[] = '[['.$groupPage->getPrefixedText().'|'.$groupName.']]';
1266                                         } else {
1267                                                 $groups[] = $groupName;
1268                                         }
1269                                 }
1270                         }
1271                         $n = count( $groups );
1272                         $groups = implode( ', ', $groups );
1273                         switch( $n ) {
1274                                 case 0:
1275                                 case 1:
1276                                 case 2:
1277                                         $return = array( "badaccess-group$n", $groups );
1278                                         break;
1279                                 default:
1280                                         $return = array( 'badaccess-groups', $groups );
1281                         }
1282                         $errors[] = $return;
1283                 }
1284
1285                 wfProfileOut( __METHOD__ );
1286                 return $errors;
1287         }
1288
1289         /**
1290          * Is this title subject to title protection?
1291          * @return mixed An associative array representing any existent title
1292          *   protection, or false if there's none.
1293          */
1294         private function getTitleProtection() {
1295                 // Can't protect pages in special namespaces
1296                 if ( $this->getNamespace() < 0 ) {
1297                         return false;
1298                 }
1299
1300                 $dbr = wfGetDB( DB_SLAVE );
1301                 $res = $dbr->select( 'protected_titles', '*',
1302                         array ('pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey()) );
1303
1304                 if ($row = $dbr->fetchRow( $res )) {
1305                         return $row;
1306                 } else {
1307                         return false;
1308                 }
1309         }
1310
1311         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
1312                 global $wgGroupPermissions,$wgUser,$wgContLang;
1313
1314                 if ($create_perm == implode(',',$this->getRestrictions('create'))
1315                         && $expiry == $this->mRestrictionsExpiry) {
1316                         // No change
1317                         return true;
1318                 }
1319
1320                 list ($namespace, $title) = array( $this->getNamespace(), $this->getDBkey() );
1321
1322                 $dbw = wfGetDB( DB_MASTER );
1323
1324                 $encodedExpiry = Block::encodeExpiry($expiry, $dbw );
1325
1326                 $expiry_description = '';
1327                 if ( $encodedExpiry != 'infinity' ) {
1328                         $expiry_description = ' (' . wfMsgForContent( 'protect-expiring', $wgContLang->timeanddate( $expiry ) ).')';
1329                 }
1330
1331                 # Update protection table
1332                 if ($create_perm != '' ) {
1333                         $dbw->replace( 'protected_titles', array(array('pt_namespace', 'pt_title')),
1334                                 array( 'pt_namespace' => $namespace, 'pt_title' => $title
1335                                         , 'pt_create_perm' => $create_perm
1336                                         , 'pt_timestamp' => Block::encodeExpiry(wfTimestampNow(), $dbw)
1337                                         , 'pt_expiry' => $encodedExpiry
1338                                         , 'pt_user' => $wgUser->getId(), 'pt_reason' => $reason ), __METHOD__  );
1339                 } else {
1340                         $dbw->delete( 'protected_titles', array( 'pt_namespace' => $namespace,
1341                                 'pt_title' => $title ), __METHOD__ );
1342                 }
1343                 # Update the protection log
1344                 $log = new LogPage( 'protect' );
1345
1346                 if( $create_perm ) {
1347                         $log->addEntry( $this->mRestrictions['create'] ? 'modify' : 'protect', $this, trim( $reason . " [create=$create_perm] $expiry_description" ) );
1348                 } else {
1349                         $log->addEntry( 'unprotect', $this, $reason );
1350                 }
1351
1352                 return true;
1353         }
1354
1355         /**
1356          * Remove any title protection (due to page existing
1357          */
1358         public function deleteTitleProtection() {
1359                 $dbw = wfGetDB( DB_MASTER );
1360
1361                 $dbw->delete( 'protected_titles',
1362                         array ('pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey()), __METHOD__ );
1363         }
1364
1365         /**
1366          * Can $wgUser edit this page?
1367          * @return boolean
1368          * @deprecated use userCan('edit')
1369          */
1370         public function userCanEdit( $doExpensiveQueries = true ) {
1371                 return $this->userCan( 'edit', $doExpensiveQueries );
1372         }
1373
1374         /**
1375          * Can $wgUser create this page?
1376          * @return boolean
1377          * @deprecated use userCan('create')
1378          */
1379         public function userCanCreate( $doExpensiveQueries = true ) {
1380                 return $this->userCan( 'create', $doExpensiveQueries );
1381         }
1382
1383         /**
1384          * Can $wgUser move this page?
1385          * @return boolean
1386          * @deprecated use userCan('move')
1387          */
1388         public function userCanMove( $doExpensiveQueries = true ) {
1389                 return $this->userCan( 'move', $doExpensiveQueries );
1390         }
1391
1392         /**
1393          * Would anybody with sufficient privileges be able to move this page?
1394          * Some pages just aren't movable.
1395          *
1396          * @return boolean
1397          */
1398         public function isMovable() {
1399                 return MWNamespace::isMovable( $this->getNamespace() )
1400                         && $this->getInterwiki() == '';
1401         }
1402
1403         /**
1404          * Can $wgUser read this page?
1405          * @return boolean
1406          * @todo fold these checks into userCan()
1407          */
1408         public function userCanRead() {
1409                 global $wgUser, $wgGroupPermissions;
1410
1411                 $result = null;
1412                 wfRunHooks( 'userCan', array( &$this, &$wgUser, 'read', &$result ) );
1413                 if ( $result !== null ) {
1414                         return $result;
1415                 }
1416
1417                 # Shortcut for public wikis, allows skipping quite a bit of code
1418                 if ($wgGroupPermissions['*']['read'])
1419                         return true;
1420
1421                 if( $wgUser->isAllowed( 'read' ) ) {
1422                         return true;
1423                 } else {
1424                         global $wgWhitelistRead;
1425
1426                         /**
1427                          * Always grant access to the login page.
1428                          * Even anons need to be able to log in.
1429                         */
1430                         if( $this->isSpecial( 'Userlogin' ) || $this->isSpecial( 'Resetpass' ) ) {
1431                                 return true;
1432                         }
1433
1434                         /**
1435                          * Bail out if there isn't whitelist
1436                          */
1437                         if( !is_array($wgWhitelistRead) ) {
1438                                 return false;
1439                         }
1440
1441                         /**
1442                          * Check for explicit whitelisting
1443                          */
1444                         $name = $this->getPrefixedText();
1445                         if( in_array( $name, $wgWhitelistRead, true ) )
1446                                 return true;
1447
1448                         /**
1449                          * Old settings might have the title prefixed with
1450                          * a colon for main-namespace pages
1451                          */
1452                         if( $this->getNamespace() == NS_MAIN ) {
1453                                 if( in_array( ':' . $name, $wgWhitelistRead ) )
1454                                         return true;
1455                         }
1456
1457                         /**
1458                          * If it's a special page, ditch the subpage bit
1459                          * and check again
1460                          */
1461                         if( $this->getNamespace() == NS_SPECIAL ) {
1462                                 $name = $this->getDBkey();
1463                                 list( $name, /* $subpage */) = SpecialPage::resolveAliasWithSubpage( $name );
1464                                 if ( $name === false ) {
1465                                         # Invalid special page, but we show standard login required message
1466                                         return false;
1467                                 }
1468
1469                                 $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
1470                                 if( in_array( $pure, $wgWhitelistRead, true ) )
1471                                         return true;
1472                         }
1473
1474                 }
1475                 return false;
1476         }
1477
1478         /**
1479          * Is this a talk page of some sort?
1480          * @return bool
1481          */
1482         public function isTalkPage() {
1483                 return MWNamespace::isTalk( $this->getNamespace() );
1484         }
1485
1486         /**
1487          * Is this a subpage?
1488          * @return bool
1489          */
1490         public function isSubpage() {
1491                 global $wgNamespacesWithSubpages;
1492
1493                 if( isset( $wgNamespacesWithSubpages[ $this->mNamespace ] ) ) {
1494                         return ( strpos( $this->getText(), '/' ) !== false && $wgNamespacesWithSubpages[ $this->mNamespace ] == true );
1495                 } else {
1496                         return false;
1497                 }
1498         }
1499
1500         /**
1501          * Could this page contain custom CSS or JavaScript, based
1502          * on the title?
1503          *
1504          * @return bool
1505          */
1506         public function isCssOrJsPage() {
1507                 return $this->mNamespace == NS_MEDIAWIKI
1508                         && preg_match( '!\.(?:css|js)$!u', $this->mTextform ) > 0;
1509         }
1510
1511         /**
1512          * Is this a .css or .js subpage of a user page?
1513          * @return bool
1514          */
1515         public function isCssJsSubpage() {
1516                 return ( NS_USER == $this->mNamespace and preg_match("/\\/.*\\.(?:css|js)$/", $this->mTextform ) );
1517         }
1518         /**
1519          * Is this a *valid* .css or .js subpage of a user page?
1520          * Check that the corresponding skin exists
1521          */
1522         public function isValidCssJsSubpage() {
1523                 if ( $this->isCssJsSubpage() ) {
1524                         $skinNames = Skin::getSkinNames();
1525                         return array_key_exists( $this->getSkinFromCssJsSubpage(), $skinNames );
1526                 } else {
1527                         return false;
1528                 }
1529         }
1530         /**
1531          * Trim down a .css or .js subpage title to get the corresponding skin name
1532          */
1533         public function getSkinFromCssJsSubpage() {
1534                 $subpage = explode( '/', $this->mTextform );
1535                 $subpage = $subpage[ count( $subpage ) - 1 ];
1536                 return( str_replace( array( '.css', '.js' ), array( '', '' ), $subpage ) );
1537         }
1538         /**
1539          * Is this a .css subpage of a user page?
1540          * @return bool
1541          */
1542         public function isCssSubpage() {
1543                 return ( NS_USER == $this->mNamespace && preg_match("/\\/.*\\.css$/", $this->mTextform ) );
1544         }
1545         /**
1546          * Is this a .js subpage of a user page?
1547          * @return bool
1548          */
1549         public function isJsSubpage() {
1550                 return ( NS_USER == $this->mNamespace && preg_match("/\\/.*\\.js$/", $this->mTextform ) );
1551         }
1552         /**
1553          * Protect css/js subpages of user pages: can $wgUser edit
1554          * this page?
1555          *
1556          * @return boolean
1557          * @todo XXX: this might be better using restrictions
1558          */
1559         public function userCanEditCssJsSubpage() {
1560                 global $wgUser;
1561                 return ( $wgUser->isAllowed('editusercssjs') || preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1562         }
1563
1564         /**
1565          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
1566          *
1567          * @return bool If the page is subject to cascading restrictions.
1568          */
1569         public function isCascadeProtected() {
1570                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
1571                 return ( $sources > 0 );
1572         }
1573
1574         /**
1575          * Cascading protection: Get the source of any cascading restrictions on this page.
1576          *
1577          * @param $get_pages bool Whether or not to retrieve the actual pages that the restrictions have come from.
1578          * @return array( mixed title array, restriction array)
1579          * 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.
1580          * The restriction array is an array of each type, each of which contains an array of unique groups
1581          */
1582         public function getCascadeProtectionSources( $get_pages = true ) {
1583                 global $wgEnableCascadingProtection, $wgRestrictionTypes;
1584
1585                 # Define our dimension of restrictions types
1586                 $pagerestrictions = array();
1587                 foreach( $wgRestrictionTypes as $action )
1588                         $pagerestrictions[$action] = array();
1589
1590                 if (!$wgEnableCascadingProtection)
1591                         return array( false, $pagerestrictions );
1592
1593                 if ( isset( $this->mCascadeSources ) && $get_pages ) {
1594                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
1595                 } else if ( isset( $this->mHasCascadingRestrictions ) && !$get_pages ) {
1596                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
1597                 }
1598
1599                 wfProfileIn( __METHOD__ );
1600
1601                 $dbr = wfGetDb( DB_SLAVE );
1602
1603                 if ( $this->getNamespace() == NS_IMAGE ) {
1604                         $tables = array ('imagelinks', 'page_restrictions');
1605                         $where_clauses = array(
1606                                 'il_to' => $this->getDBkey(),
1607                                 'il_from=pr_page',
1608                                 'pr_cascade' => 1 );
1609                 } else {
1610                         $tables = array ('templatelinks', 'page_restrictions');
1611                         $where_clauses = array(
1612                                 'tl_namespace' => $this->getNamespace(),
1613                                 'tl_title' => $this->getDBkey(),
1614                                 'tl_from=pr_page',
1615                                 'pr_cascade' => 1 );
1616                 }
1617
1618                 if ( $get_pages ) {
1619                         $cols = array('pr_page', 'page_namespace', 'page_title', 'pr_expiry', 'pr_type', 'pr_level' );
1620                         $where_clauses[] = 'page_id=pr_page';
1621                         $tables[] = 'page';
1622                 } else {
1623                         $cols = array( 'pr_expiry' );
1624                 }
1625
1626                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
1627
1628                 $sources = $get_pages ? array() : false;
1629                 $now = wfTimestampNow();
1630                 $purgeExpired = false;
1631
1632                 while( $row = $dbr->fetchObject( $res ) ) {
1633                         $expiry = Block::decodeExpiry( $row->pr_expiry );
1634                         if( $expiry > $now ) {
1635                                 if ($get_pages) {
1636                                         $page_id = $row->pr_page;
1637                                         $page_ns = $row->page_namespace;
1638                                         $page_title = $row->page_title;
1639                                         $sources[$page_id] = Title::makeTitle($page_ns, $page_title);
1640                                         # Add groups needed for each restriction type if its not already there
1641                                         # Make sure this restriction type still exists
1642                                         if ( isset($pagerestrictions[$row->pr_type]) && !in_array($row->pr_level, $pagerestrictions[$row->pr_type]) ) {
1643                                                 $pagerestrictions[$row->pr_type][]=$row->pr_level;
1644                                         }
1645                                 } else {
1646                                         $sources = true;
1647                                 }
1648                         } else {
1649                                 // Trigger lazy purge of expired restrictions from the db
1650                                 $purgeExpired = true;
1651                         }
1652                 }
1653                 if( $purgeExpired ) {
1654                         Title::purgeExpiredRestrictions();
1655                 }
1656
1657                 wfProfileOut( __METHOD__ );
1658
1659                 if ( $get_pages ) {
1660                         $this->mCascadeSources = $sources;
1661                         $this->mCascadingRestrictions = $pagerestrictions;
1662                 } else {
1663                         $this->mHasCascadingRestrictions = $sources;
1664                 }
1665
1666                 return array( $sources, $pagerestrictions );
1667         }
1668
1669         function areRestrictionsCascading() {
1670                 if (!$this->mRestrictionsLoaded) {
1671                         $this->loadRestrictions();
1672                 }
1673
1674                 return $this->mCascadeRestriction;
1675         }
1676
1677         /**
1678          * Loads a string into mRestrictions array
1679          * @param resource $res restrictions as an SQL result.
1680          */
1681         private function loadRestrictionsFromRow( $res, $oldFashionedRestrictions = NULL ) {
1682                 global $wgRestrictionTypes;
1683                 $dbr = wfGetDB( DB_SLAVE );
1684
1685                 foreach( $wgRestrictionTypes as $type ){
1686                         $this->mRestrictions[$type] = array();
1687                 }
1688
1689                 $this->mCascadeRestriction = false;
1690                 $this->mRestrictionsExpiry = Block::decodeExpiry('');
1691
1692                 # Backwards-compatibility: also load the restrictions from the page record (old format).
1693
1694                 if ( $oldFashionedRestrictions == NULL ) {
1695                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions', array( 'page_id' => $this->getArticleId() ), __METHOD__ );
1696                 }
1697
1698                 if ($oldFashionedRestrictions != '') {
1699
1700                         foreach( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
1701                                 $temp = explode( '=', trim( $restrict ) );
1702                                 if(count($temp) == 1) {
1703                                         // old old format should be treated as edit/move restriction
1704                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
1705                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
1706                                 } else {
1707                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
1708                                 }
1709                         }
1710
1711                         $this->mOldRestrictions = true;
1712
1713                 }
1714
1715                 if( $dbr->numRows( $res ) ) {
1716                         # Current system - load second to make them override.
1717                         $now = wfTimestampNow();
1718                         $purgeExpired = false;
1719
1720                         while ($row = $dbr->fetchObject( $res ) ) {
1721                                 # Cycle through all the restrictions.
1722
1723                                 // Don't take care of restrictions types that aren't in $wgRestrictionTypes
1724                                 if( !in_array( $row->pr_type, $wgRestrictionTypes ) )
1725                                         continue;
1726
1727                                 // This code should be refactored, now that it's being used more generally,
1728                                 // But I don't really see any harm in leaving it in Block for now -werdna
1729                                 $expiry = Block::decodeExpiry( $row->pr_expiry );
1730
1731                                 // Only apply the restrictions if they haven't expired!
1732                                 if ( !$expiry || $expiry > $now ) {
1733                                         $this->mRestrictionsExpiry = $expiry;
1734                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
1735
1736                                         $this->mCascadeRestriction |= $row->pr_cascade;
1737                                 } else {
1738                                         // Trigger a lazy purge of expired restrictions
1739                                         $purgeExpired = true;
1740                                 }
1741                         }
1742
1743                         if( $purgeExpired ) {
1744                                 Title::purgeExpiredRestrictions();
1745                         }
1746                 }
1747
1748                 $this->mRestrictionsLoaded = true;
1749         }
1750
1751         public function loadRestrictions( $oldFashionedRestrictions = NULL ) {
1752                 if( !$this->mRestrictionsLoaded ) {
1753                         if ($this->exists()) {
1754                                 $dbr = wfGetDB( DB_SLAVE );
1755
1756                                 $res = $dbr->select( 'page_restrictions', '*',
1757                                         array ( 'pr_page' => $this->getArticleId() ), __METHOD__ );
1758
1759                                 $this->loadRestrictionsFromRow( $res, $oldFashionedRestrictions );
1760                         } else {
1761                                 $title_protection = $this->getTitleProtection();
1762
1763                                 if (is_array($title_protection)) {
1764                                         extract($title_protection);
1765
1766                                         $now = wfTimestampNow();
1767                                         $expiry = Block::decodeExpiry($pt_expiry);
1768
1769                                         if (!$expiry || $expiry > $now) {
1770                                                 // Apply the restrictions
1771                                                 $this->mRestrictionsExpiry = $expiry;
1772                                                 $this->mRestrictions['create'] = explode(',', trim($pt_create_perm) );
1773                                         } else { // Get rid of the old restrictions
1774                                                 Title::purgeExpiredRestrictions();
1775                                         }
1776                                 }
1777                                 $this->mRestrictionsLoaded = true;
1778                         }
1779                 }
1780         }
1781
1782         /**
1783          * Purge expired restrictions from the page_restrictions table
1784          */
1785         static function purgeExpiredRestrictions() {
1786                 $dbw = wfGetDB( DB_MASTER );
1787                 $dbw->delete( 'page_restrictions',
1788                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
1789                         __METHOD__ );
1790
1791                 $dbw->delete( 'protected_titles',
1792                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
1793                         __METHOD__ );
1794         }
1795
1796         /**
1797          * Accessor/initialisation for mRestrictions
1798          *
1799          * @param string $action action that permission needs to be checked for
1800          * @return array the array of groups allowed to edit this article
1801          */
1802         public function getRestrictions( $action ) {
1803                 if( !$this->mRestrictionsLoaded ) {
1804                         $this->loadRestrictions();
1805                 }
1806                 return isset( $this->mRestrictions[$action] )
1807                                 ? $this->mRestrictions[$action]
1808                                 : array();
1809         }
1810
1811         /**
1812          * Is there a version of this page in the deletion archive?
1813          * @return int the number of archived revisions
1814          */
1815         public function isDeleted() {
1816                 $fname = 'Title::isDeleted';
1817                 if ( $this->getNamespace() < 0 ) {
1818                         $n = 0;
1819                 } else {
1820                         $dbr = wfGetDB( DB_SLAVE );
1821                         $n = $dbr->selectField( 'archive', 'COUNT(*)', array( 'ar_namespace' => $this->getNamespace(),
1822                                 'ar_title' => $this->getDBkey() ), $fname );
1823                         if( $this->getNamespace() == NS_IMAGE ) {
1824                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
1825                                         array( 'fa_name' => $this->getDBkey() ), $fname );
1826                         }
1827                 }
1828                 return (int)$n;
1829         }
1830
1831         /**
1832          * Get the article ID for this Title from the link cache,
1833          * adding it if necessary
1834          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select
1835          *      for update
1836          * @return int the ID
1837          */
1838         public function getArticleID( $flags = 0 ) {
1839                 $linkCache = LinkCache::singleton();
1840                 if ( $flags & GAID_FOR_UPDATE ) {
1841                         $oldUpdate = $linkCache->forUpdate( true );
1842                         $this->mArticleID = $linkCache->addLinkObj( $this );
1843                         $linkCache->forUpdate( $oldUpdate );
1844                 } else {
1845                         if ( -1 == $this->mArticleID ) {
1846                                 $this->mArticleID = $linkCache->addLinkObj( $this );
1847                         }
1848                 }
1849                 return $this->mArticleID;
1850         }
1851
1852         /**
1853          * Is this an article that is a redirect page?
1854          * Uses link cache, adding it if necessary
1855          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select for update
1856          * @return bool
1857          */
1858         public function isRedirect( $flags = 0 ) {
1859                 if( !is_null($this->mRedirect) )
1860                         return $this->mRedirect;
1861                 # Zero for special pages.
1862                 # Also, calling getArticleID() loads the field from cache!
1863                 if( !$this->getArticleID($flags) || $this->getNamespace() == NS_SPECIAL ) {
1864                         return false;
1865                 }
1866                 $linkCache = LinkCache::singleton();
1867                 $this->mRedirect = (bool)$linkCache->getGoodLinkFieldObj( $this, 'redirect' );
1868
1869                 return $this->mRedirect;
1870         }
1871
1872         /**
1873          * What is the length of this page?
1874          * Uses link cache, adding it if necessary
1875          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select for update
1876          * @return bool
1877          */
1878         public function getLength( $flags = 0 ) {
1879                 if( $this->mLength != -1 )
1880                         return $this->mLength;
1881                 # Zero for special pages.
1882                 # Also, calling getArticleID() loads the field from cache!
1883                 if( !$this->getArticleID($flags) || $this->getNamespace() == NS_SPECIAL ) {
1884                         return 0;
1885                 }
1886                 $linkCache = LinkCache::singleton();
1887                 $this->mLength = intval( $linkCache->getGoodLinkFieldObj( $this, 'length' ) );
1888
1889                 return $this->mLength;
1890         }
1891
1892         public function getLatestRevID() {
1893                 if ($this->mLatestID !== false)
1894                         return $this->mLatestID;
1895
1896                 $db = wfGetDB(DB_SLAVE);
1897                 return $this->mLatestID = $db->selectField( 'revision',
1898                         "max(rev_id)",
1899                         array('rev_page' => $this->getArticleID()),
1900                         'Title::getLatestRevID' );
1901         }
1902
1903         /**
1904          * This clears some fields in this object, and clears any associated
1905          * keys in the "bad links" section of the link cache.
1906          *
1907          * - This is called from Article::insertNewArticle() to allow
1908          * loading of the new page_id. It's also called from
1909          * Article::doDeleteArticle()
1910          *
1911          * @param int $newid the new Article ID
1912          */
1913         public function resetArticleID( $newid ) {
1914                 $linkCache = LinkCache::singleton();
1915                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
1916
1917                 if ( 0 == $newid ) { $this->mArticleID = -1; }
1918                 else { $this->mArticleID = $newid; }
1919                 $this->mRestrictionsLoaded = false;
1920                 $this->mRestrictions = array();
1921         }
1922
1923         /**
1924          * Updates page_touched for this page; called from LinksUpdate.php
1925          * @return bool true if the update succeded
1926          */
1927         public function invalidateCache() {
1928                 global $wgUseFileCache;
1929
1930                 if ( wfReadOnly() ) {
1931                         return;
1932                 }
1933
1934                 $dbw = wfGetDB( DB_MASTER );
1935                 $success = $dbw->update( 'page',
1936                         array( /* SET */
1937                                 'page_touched' => $dbw->timestamp()
1938                         ), array( /* WHERE */
1939                                 'page_namespace' => $this->getNamespace() ,
1940                                 'page_title' => $this->getDBkey()
1941                         ), 'Title::invalidateCache'
1942                 );
1943
1944                 if ($wgUseFileCache) {
1945                         $cache = new HTMLFileCache($this);
1946                         @unlink($cache->fileCacheName());
1947                 }
1948
1949                 return $success;
1950         }
1951
1952         /**
1953          * Prefix some arbitrary text with the namespace or interwiki prefix
1954          * of this object
1955          *
1956          * @param string $name the text
1957          * @return string the prefixed text
1958          * @private
1959          */
1960         /* private */ function prefix( $name ) {
1961                 $p = '';
1962                 if ( '' != $this->mInterwiki ) {
1963                         $p = $this->mInterwiki . ':';
1964                 }
1965                 if ( 0 != $this->mNamespace ) {
1966                         $p .= $this->getNsText() . ':';
1967                 }
1968                 return $p . $name;
1969         }
1970
1971         /**
1972          * Secure and split - main initialisation function for this object
1973          *
1974          * Assumes that mDbkeyform has been set, and is urldecoded
1975          * and uses underscores, but not otherwise munged.  This function
1976          * removes illegal characters, splits off the interwiki and
1977          * namespace prefixes, sets the other forms, and canonicalizes
1978          * everything.
1979          * @return bool true on success
1980          */
1981         private function secureAndSplit() {
1982                 global $wgContLang, $wgLocalInterwiki, $wgCapitalLinks;
1983
1984                 # Initialisation
1985                 static $rxTc = false;
1986                 if( !$rxTc ) {
1987                         # Matching titles will be held as illegal.
1988                         $rxTc = '/' .
1989                                 # Any character not allowed is forbidden...
1990                                 '[^' . Title::legalChars() . ']' .
1991                                 # URL percent encoding sequences interfere with the ability
1992                                 # to round-trip titles -- you can't link to them consistently.
1993                                 '|%[0-9A-Fa-f]{2}' .
1994                                 # XML/HTML character references produce similar issues.
1995                                 '|&[A-Za-z0-9\x80-\xff]+;' .
1996                                 '|&#[0-9]+;' .
1997                                 '|&#x[0-9A-Fa-f]+;' .
1998                                 '/S';
1999                 }
2000
2001                 $this->mInterwiki = $this->mFragment = '';
2002                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2003
2004                 $dbkey = $this->mDbkeyform;
2005
2006                 # Strip Unicode bidi override characters.
2007                 # Sometimes they slip into cut-n-pasted page titles, where the
2008                 # override chars get included in list displays.
2009                 $dbkey = str_replace( "\xE2\x80\x8E", '', $dbkey ); // 200E LEFT-TO-RIGHT MARK
2010                 $dbkey = str_replace( "\xE2\x80\x8F", '', $dbkey ); // 200F RIGHT-TO-LEFT MARK
2011
2012                 # Clean up whitespace
2013                 #
2014                 $dbkey = preg_replace( '/[ _]+/', '_', $dbkey );
2015                 $dbkey = trim( $dbkey, '_' );
2016
2017                 if ( '' == $dbkey ) {
2018                         return false;
2019                 }
2020
2021                 if( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2022                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2023                         return false;
2024                 }
2025
2026                 $this->mDbkeyform = $dbkey;
2027
2028                 # Initial colon indicates main namespace rather than specified default
2029                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
2030                 if ( ':' == $dbkey{0} ) {
2031                         $this->mNamespace = NS_MAIN;
2032                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
2033                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
2034                 }
2035
2036                 # Namespace or interwiki prefix
2037                 $firstPass = true;
2038                 do {
2039                         $m = array();
2040                         if ( preg_match( "/^(.+?)_*:_*(.*)$/S", $dbkey, $m ) ) {
2041                                 $p = $m[1];
2042                                 if ( $ns = $wgContLang->getNsIndex( $p )) {
2043                                         # Ordinary namespace
2044                                         $dbkey = $m[2];
2045                                         $this->mNamespace = $ns;
2046                                 } elseif( $this->getInterwikiLink( $p ) ) {
2047                                         if( !$firstPass ) {
2048                                                 # Can't make a local interwiki link to an interwiki link.
2049                                                 # That's just crazy!
2050                                                 return false;
2051                                         }
2052
2053                                         # Interwiki link
2054                                         $dbkey = $m[2];
2055                                         $this->mInterwiki = $wgContLang->lc( $p );
2056
2057                                         # Redundant interwiki prefix to the local wiki
2058                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
2059                                                 if( $dbkey == '' ) {
2060                                                         # Can't have an empty self-link
2061                                                         return false;
2062                                                 }
2063                                                 $this->mInterwiki = '';
2064                                                 $firstPass = false;
2065                                                 # Do another namespace split...
2066                                                 continue;
2067                                         }
2068
2069                                         # If there's an initial colon after the interwiki, that also
2070                                         # resets the default namespace
2071                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
2072                                                 $this->mNamespace = NS_MAIN;
2073                                                 $dbkey = substr( $dbkey, 1 );
2074                                         }
2075                                 }
2076                                 # If there's no recognized interwiki or namespace,
2077                                 # then let the colon expression be part of the title.
2078                         }
2079                         break;
2080                 } while( true );
2081
2082                 # We already know that some pages won't be in the database!
2083                 #
2084                 if ( '' != $this->mInterwiki || NS_SPECIAL == $this->mNamespace ) {
2085                         $this->mArticleID = 0;
2086                 }
2087                 $fragment = strstr( $dbkey, '#' );
2088                 if ( false !== $fragment ) {
2089                         $this->setFragment( $fragment );
2090                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
2091                         # remove whitespace again: prevents "Foo_bar_#"
2092                         # becoming "Foo_bar_"
2093                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
2094                 }
2095
2096                 # Reject illegal characters.
2097                 #
2098                 if( preg_match( $rxTc, $dbkey ) ) {
2099                         return false;
2100                 }
2101
2102                 /**
2103                  * Pages with "/./" or "/../" appearing in the URLs will
2104                  * often be unreachable due to the way web browsers deal
2105                  * with 'relative' URLs. Forbid them explicitly.
2106                  */
2107                 if ( strpos( $dbkey, '.' ) !== false &&
2108                      ( $dbkey === '.' || $dbkey === '..' ||
2109                        strpos( $dbkey, './' ) === 0  ||
2110                        strpos( $dbkey, '../' ) === 0 ||
2111                        strpos( $dbkey, '/./' ) !== false ||
2112                        strpos( $dbkey, '/../' ) !== false  ||
2113                        substr( $dbkey, -2 ) == '/.' ||
2114                        substr( $dbkey, -3 ) == '/..' ) )
2115                 {
2116                         return false;
2117                 }
2118
2119                 /**
2120                  * Magic tilde sequences? Nu-uh!
2121                  */
2122                 if( strpos( $dbkey, '~~~' ) !== false ) {
2123                         return false;
2124                 }
2125
2126                 /**
2127                  * Limit the size of titles to 255 bytes.
2128                  * This is typically the size of the underlying database field.
2129                  * We make an exception for special pages, which don't need to be stored
2130                  * in the database, and may edge over 255 bytes due to subpage syntax
2131                  * for long titles, e.g. [[Special:Block/Long name]]
2132                  */
2133                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
2134                   strlen( $dbkey ) > 512 )
2135                 {
2136                         return false;
2137                 }
2138
2139                 /**
2140                  * Normally, all wiki links are forced to have
2141                  * an initial capital letter so [[foo]] and [[Foo]]
2142                  * point to the same place.
2143                  *
2144                  * Don't force it for interwikis, since the other
2145                  * site might be case-sensitive.
2146                  */
2147                 $this->mUserCaseDBKey = $dbkey;
2148                 if( $wgCapitalLinks && $this->mInterwiki == '') {
2149                         $dbkey = $wgContLang->ucfirst( $dbkey );
2150                 }
2151
2152                 /**
2153                  * Can't make a link to a namespace alone...
2154                  * "empty" local links can only be self-links
2155                  * with a fragment identifier.
2156                  */
2157                 if( $dbkey == '' &&
2158                         $this->mInterwiki == '' &&
2159                         $this->mNamespace != NS_MAIN ) {
2160                         return false;
2161                 }
2162                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
2163                 // IP names are not allowed for accounts, and can only be referring to
2164                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
2165                 // there are numerous ways to present the same IP. Having sp:contribs scan
2166                 // them all is silly and having some show the edits and others not is
2167                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
2168                 $dbkey = ($this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK) ?
2169                         IP::sanitizeIP( $dbkey ) : $dbkey;
2170                 // Any remaining initial :s are illegal.
2171                 if ( $dbkey !== '' && ':' == $dbkey{0} ) {
2172                         return false;
2173                 }
2174
2175                 # Fill fields
2176                 $this->mDbkeyform = $dbkey;
2177                 $this->mUrlform = wfUrlencode( $dbkey );
2178
2179                 $this->mTextform = str_replace( '_', ' ', $dbkey );
2180
2181                 return true;
2182         }
2183
2184         /**
2185          * Set the fragment for this title
2186          * This is kind of bad, since except for this rarely-used function, Title objects
2187          * are immutable. The reason this is here is because it's better than setting the
2188          * members directly, which is what Linker::formatComment was doing previously.
2189          *
2190          * @param string $fragment text
2191          * @todo clarify whether access is supposed to be public (was marked as "kind of public")
2192          */
2193         public function setFragment( $fragment ) {
2194                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
2195         }
2196
2197         /**
2198          * Get a Title object associated with the talk page of this article
2199          * @return Title the object for the talk page
2200          */
2201         public function getTalkPage() {
2202                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
2203         }
2204
2205         /**
2206          * Get a title object associated with the subject page of this
2207          * talk page
2208          *
2209          * @return Title the object for the subject page
2210          */
2211         public function getSubjectPage() {
2212                 return Title::makeTitle( MWNamespace::getSubject( $this->getNamespace() ), $this->getDBkey() );
2213         }
2214
2215         /**
2216          * Get an array of Title objects linking to this Title
2217          * Also stores the IDs in the link cache.
2218          *
2219          * WARNING: do not use this function on arbitrary user-supplied titles!
2220          * On heavily-used templates it will max out the memory.
2221          *
2222          * @param string $options may be FOR UPDATE
2223          * @return array the Title objects linking here
2224          */
2225         public function getLinksTo( $options = '', $table = 'pagelinks', $prefix = 'pl' ) {
2226                 $linkCache = LinkCache::singleton();
2227
2228                 if ( $options ) {
2229                         $db = wfGetDB( DB_MASTER );
2230                 } else {
2231                         $db = wfGetDB( DB_SLAVE );
2232                 }
2233
2234                 $res = $db->select( array( 'page', $table ),
2235                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect' ),
2236                         array(
2237                                 "{$prefix}_from=page_id",
2238                                 "{$prefix}_namespace" => $this->getNamespace(),
2239                                 "{$prefix}_title"     => $this->getDBkey() ),
2240                         'Title::getLinksTo',
2241                         $options );
2242
2243                 $retVal = array();
2244                 if ( $db->numRows( $res ) ) {
2245                         while ( $row = $db->fetchObject( $res ) ) {
2246                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
2247                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj, $row->page_len, $row->page_is_redirect );
2248                                         $retVal[] = $titleObj;
2249                                 }
2250                         }
2251                 }
2252                 $db->freeResult( $res );
2253                 return $retVal;
2254         }
2255
2256         /**
2257          * Get an array of Title objects using this Title as a template
2258          * Also stores the IDs in the link cache.
2259          *
2260          * WARNING: do not use this function on arbitrary user-supplied titles!
2261          * On heavily-used templates it will max out the memory.
2262          *
2263          * @param string $options may be FOR UPDATE
2264          * @return array the Title objects linking here
2265          */
2266         public function getTemplateLinksTo( $options = '' ) {
2267                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
2268         }
2269
2270         /**
2271          * Get an array of Title objects referring to non-existent articles linked from this page
2272          *
2273          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
2274          * @param string $options may be FOR UPDATE
2275          * @return array the Title objects
2276          */
2277         public function getBrokenLinksFrom( $options = '' ) {
2278                 if ( $this->getArticleId() == 0 ) {
2279                         # All links from article ID 0 are false positives
2280                         return array();
2281                 }
2282
2283                 if ( $options ) {
2284                         $db = wfGetDB( DB_MASTER );
2285                 } else {
2286                         $db = wfGetDB( DB_SLAVE );
2287                 }
2288
2289                 $res = $db->safeQuery(
2290                           "SELECT pl_namespace, pl_title
2291                              FROM !
2292                         LEFT JOIN !
2293                                ON pl_namespace=page_namespace
2294                               AND pl_title=page_title
2295                             WHERE pl_from=?
2296                               AND page_namespace IS NULL
2297                                   !",
2298                         $db->tableName( 'pagelinks' ),
2299                         $db->tableName( 'page' ),
2300                         $this->getArticleId(),
2301                         $options );
2302
2303                 $retVal = array();
2304                 if ( $db->numRows( $res ) ) {
2305                         while ( $row = $db->fetchObject( $res ) ) {
2306                                 $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
2307                         }
2308                 }
2309                 $db->freeResult( $res );
2310                 return $retVal;
2311         }
2312
2313
2314         /**
2315          * Get a list of URLs to purge from the Squid cache when this
2316          * page changes
2317          *
2318          * @return array the URLs
2319          */
2320         public function getSquidURLs() {
2321                 global $wgContLang;
2322
2323                 $urls = array(
2324                         $this->getInternalURL(),
2325                         $this->getInternalURL( 'action=history' )
2326                 );
2327
2328                 // purge variant urls as well
2329                 if($wgContLang->hasVariants()){
2330                         $variants = $wgContLang->getVariants();
2331                         foreach($variants as $vCode){
2332                                 if($vCode==$wgContLang->getCode()) continue; // we don't want default variant
2333                                 $urls[] = $this->getInternalURL('',$vCode);
2334                         }
2335                 }
2336
2337                 return $urls;
2338         }
2339
2340         public function purgeSquid() {
2341                 global $wgUseSquid;
2342                 if ( $wgUseSquid ) {
2343                         $urls = $this->getSquidURLs();
2344                         $u = new SquidUpdate( $urls );
2345                         $u->doUpdate();
2346                 }
2347         }
2348
2349         /**
2350          * Move this page without authentication
2351          * @param Title &$nt the new page Title
2352          */
2353         public function moveNoAuth( &$nt ) {
2354                 return $this->moveTo( $nt, false );
2355         }
2356
2357         /**
2358          * Check whether a given move operation would be valid.
2359          * Returns true if ok, or a message key string for an error message
2360          * if invalid. (Scarrrrry ugly interface this.)
2361          * @param Title &$nt the new title
2362          * @param bool $auth indicates whether $wgUser's permissions
2363          *      should be checked
2364          * @return mixed true on success, message name on failure
2365          */
2366         public function isValidMoveOperation( &$nt, $auth = true ) {
2367                 if( !$this or !$nt ) {
2368                         return 'badtitletext';
2369                 }
2370                 if( $this->equals( $nt ) ) {
2371                         return 'selfmove';
2372                 }
2373                 if( !$this->isMovable() || !$nt->isMovable() ) {
2374                         return 'immobile_namespace';
2375                 }
2376
2377                 $oldid = $this->getArticleID();
2378                 $newid = $nt->getArticleID();
2379
2380                 if ( strlen( $nt->getDBkey() ) < 1 ) {
2381                         return 'articleexists';
2382                 }
2383                 if ( ( '' == $this->getDBkey() ) ||
2384                          ( !$oldid ) ||
2385                      ( '' == $nt->getDBkey() ) ) {
2386                         return 'badarticleerror';
2387                 }
2388
2389                 if ( $auth ) {
2390                         global $wgUser;
2391                         $errors = array_merge($this->getUserPermissionsErrors('move', $wgUser),
2392                                         $this->getUserPermissionsErrors('edit', $wgUser),
2393                                         $nt->getUserPermissionsErrors('move', $wgUser),
2394                                         $nt->getUserPermissionsErrors('edit', $wgUser));
2395                         if($errors !== array())
2396                                 return $errors[0][0];
2397                 }
2398
2399                 global $wgUser;
2400                 $err = null;
2401                 if( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err ) ) ) {
2402                         return 'hookaborted';
2403                 }
2404
2405                 # The move is allowed only if (1) the target doesn't exist, or
2406                 # (2) the target is a redirect to the source, and has no history
2407                 # (so we can undo bad moves right after they're done).
2408
2409                 if ( 0 != $newid ) { # Target exists; check for validity
2410                         if ( ! $this->isValidMoveTarget( $nt ) ) {
2411                                 return 'articleexists';
2412                         }
2413                 } else {
2414                         $tp = $nt->getTitleProtection();
2415                         if ( $tp and !$wgUser->isAllowed( $tp['pt_create_perm'] ) ) {
2416                                 return 'cantmove-titleprotected';
2417                         }
2418                 }
2419                 return true;
2420         }
2421
2422         /**
2423          * Move a title to a new location
2424          * @param Title &$nt the new title
2425          * @param bool $auth indicates whether $wgUser's permissions
2426          *      should be checked
2427          * @param string $reason The reason for the move
2428          * @param bool $createRedirect Whether to create a redirect from the old title to the new title.
2429          *  Ignored if the user doesn't have the suppressredirect right.
2430          * @return mixed true on success, message name on failure
2431          */
2432         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
2433                 $err = $this->isValidMoveOperation( $nt, $auth );
2434                 if( is_string( $err ) ) {
2435                         return $err;
2436                 }
2437
2438                 $pageid = $this->getArticleID();
2439                 if( $nt->exists() ) {
2440                         $this->moveOverExistingRedirect( $nt, $reason, $createRedirect );
2441                         $pageCountChange = ($createRedirect ? 0 : -1);
2442                 } else { # Target didn't exist, do normal move.
2443                         $this->moveToNewTitle( $nt, $reason, $createRedirect );
2444                         $pageCountChange = ($createRedirect ? 1 : 0);
2445                 }
2446                 $redirid = $this->getArticleID();
2447
2448                 // Category memberships include a sort key which may be customized.
2449                 // If it's left as the default (the page title), we need to update
2450                 // the sort key to match the new title.
2451                 //
2452                 // Be careful to avoid resetting cl_timestamp, which may disturb
2453                 // time-based lists on some sites.
2454                 //
2455                 // Warning -- if the sort key is *explicitly* set to the old title,
2456                 // we can't actually distinguish it from a default here, and it'll
2457                 // be set to the new title even though it really shouldn't.
2458                 // It'll get corrected on the next edit, but resetting cl_timestamp.
2459                 $dbw = wfGetDB( DB_MASTER );
2460                 $dbw->update( 'categorylinks',
2461                         array(
2462                                 'cl_sortkey' => $nt->getPrefixedText(),
2463                                 'cl_timestamp=cl_timestamp' ),
2464                         array(
2465                                 'cl_from' => $pageid,
2466                                 'cl_sortkey' => $this->getPrefixedText() ),
2467                         __METHOD__ );
2468
2469                 # Update watchlists
2470
2471                 $oldnamespace = $this->getNamespace() & ~1;
2472                 $newnamespace = $nt->getNamespace() & ~1;
2473                 $oldtitle = $this->getDBkey();
2474                 $newtitle = $nt->getDBkey();
2475
2476                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
2477                         WatchedItem::duplicateEntries( $this, $nt );
2478                 }
2479
2480                 # Update search engine
2481                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
2482                 $u->doUpdate();
2483                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
2484                 $u->doUpdate();
2485
2486                 # Update site_stats
2487                 if( $this->isContentPage() && !$nt->isContentPage() ) {
2488                         # No longer a content page
2489                         # Not viewed, edited, removing
2490                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange );
2491                 } elseif( !$this->isContentPage() && $nt->isContentPage() ) {
2492                         # Now a content page
2493                         # Not viewed, edited, adding
2494                         $u = new SiteStatsUpdate( 0, 1, +1, $pageCountChange );
2495                 } elseif( $pageCountChange ) {
2496                         # Redirect added
2497                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
2498                 } else {
2499                         # Nothing special
2500                         $u = false;
2501                 }
2502                 if( $u )
2503                         $u->doUpdate();
2504                 # Update message cache for interface messages
2505                 if( $nt->getNamespace() == NS_MEDIAWIKI ) {
2506                         global $wgMessageCache;
2507                         $oldarticle = new Article( $this );
2508                         $wgMessageCache->replace( $this->getDBkey(), $oldarticle->getContent() );
2509                         $newarticle = new Article( $nt );
2510                         $wgMessageCache->replace( $nt->getDBkey(), $newarticle->getContent() );
2511                 }
2512
2513                 global $wgUser;
2514                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
2515                 return true;
2516         }
2517
2518         /**
2519          * Move page to a title which is at present a redirect to the
2520          * source page
2521          *
2522          * @param Title &$nt the page to move to, which should currently
2523          *      be a redirect
2524          * @param string $reason The reason for the move
2525          * @param bool $createRedirect Whether to leave a redirect at the old title.
2526          *  Ignored if the user doesn't have the suppressredirect right
2527          */
2528         private function moveOverExistingRedirect( &$nt, $reason = '', $createRedirect = true ) {
2529                 global $wgUseSquid, $wgUser;
2530                 $fname = 'Title::moveOverExistingRedirect';
2531                 $comment = wfMsgForContent( '1movedto2_redir', $this->getPrefixedText(), $nt->getPrefixedText() );
2532
2533                 if ( $reason ) {
2534                         $comment .= ": $reason";
2535                 }
2536
2537                 $now = wfTimestampNow();
2538                 $newid = $nt->getArticleID();
2539                 $oldid = $this->getArticleID();
2540                 $dbw = wfGetDB( DB_MASTER );
2541
2542                 # Delete the old redirect. We don't save it to history since
2543                 # by definition if we've got here it's rather uninteresting.
2544                 # We have to remove it so that the next step doesn't trigger
2545                 # a conflict on the unique namespace+title index...
2546                 $dbw->delete( 'page', array( 'page_id' => $newid ), $fname );
2547                 if ( !$dbw->cascadingDeletes() ) {
2548                         $dbw->delete( 'revision', array( 'rev_page' => $newid ), __METHOD__ );
2549                         global $wgUseTrackbacks;
2550                         if ($wgUseTrackbacks)
2551                                 $dbw->delete( 'trackbacks', array( 'tb_page' => $newid ), __METHOD__ );
2552                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
2553                         $dbw->delete( 'imagelinks', array( 'il_from' => $newid ), __METHOD__ );
2554                         $dbw->delete( 'categorylinks', array( 'cl_from' => $newid ), __METHOD__ );
2555                         $dbw->delete( 'templatelinks', array( 'tl_from' => $newid ), __METHOD__ );
2556                         $dbw->delete( 'externallinks', array( 'el_from' => $newid ), __METHOD__ );
2557                         $dbw->delete( 'langlinks', array( 'll_from' => $newid ), __METHOD__ );
2558                         $dbw->delete( 'redirect', array( 'rd_from' => $newid ), __METHOD__ );
2559                 }
2560
2561                 # Save a null revision in the page's history notifying of the move
2562                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
2563                 $nullRevId = $nullRevision->insertOn( $dbw );
2564
2565                 # Change the name of the target page:
2566                 $dbw->update( 'page',
2567                         /* SET */ array(
2568                                 'page_touched'   => $dbw->timestamp($now),
2569                                 'page_namespace' => $nt->getNamespace(),
2570                                 'page_title'     => $nt->getDBkey(),
2571                                 'page_latest'    => $nullRevId,
2572                         ),
2573                         /* WHERE */ array( 'page_id' => $oldid ),
2574                         $fname
2575                 );
2576                 $nt->resetArticleID( $oldid );
2577
2578                 # Recreate the redirect, this time in the other direction.
2579                 if($createRedirect || !$wgUser->isAllowed('suppressredirect'))
2580                 {
2581                         $mwRedir = MagicWord::get( 'redirect' );
2582                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
2583                         $redirectArticle = new Article( $this );
2584                         $newid = $redirectArticle->insertOn( $dbw );
2585                         $redirectRevision = new Revision( array(
2586                                 'page'    => $newid,
2587                                 'comment' => $comment,
2588                                 'text'    => $redirectText ) );
2589                         $redirectRevision->insertOn( $dbw );
2590                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
2591
2592                         # Now, we record the link from the redirect to the new title.
2593                         # It should have no other outgoing links...
2594                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), $fname );
2595                         $dbw->insert( 'pagelinks',
2596                                 array(
2597                                         'pl_from'      => $newid,
2598                                         'pl_namespace' => $nt->getNamespace(),
2599                                         'pl_title'     => $nt->getDBkey() ),
2600                                 $fname );
2601                 } else {
2602                         $this->resetArticleID( 0 );
2603                 }
2604
2605                 # Log the move
2606                 $log = new LogPage( 'move' );
2607                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText() ) );
2608
2609                 # Purge squid
2610                 if ( $wgUseSquid ) {
2611                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
2612                         $u = new SquidUpdate( $urls );
2613                         $u->doUpdate();
2614                 }
2615         }
2616
2617         /**
2618          * Move page to non-existing title.
2619          * @param Title &$nt the new Title
2620          * @param string $reason The reason for the move
2621          * @param bool $createRedirect Whether to create a redirect from the old title to the new title
2622          *  Ignored if the user doesn't have the suppressredirect right
2623          */
2624         private function moveToNewTitle( &$nt, $reason = '', $createRedirect = true ) {
2625                 global $wgUseSquid, $wgUser;
2626                 $fname = 'MovePageForm::moveToNewTitle';
2627                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
2628                 if ( $reason ) {
2629                         $comment .= ": $reason";
2630                 }
2631
2632                 $newid = $nt->getArticleID();
2633                 $oldid = $this->getArticleID();
2634                 $dbw = wfGetDB( DB_MASTER );
2635                 $now = $dbw->timestamp();
2636
2637                 # Save a null revision in the page's history notifying of the move
2638                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
2639                 $nullRevId = $nullRevision->insertOn( $dbw );
2640
2641                 # Rename page entry
2642                 $dbw->update( 'page',
2643                         /* SET */ array(
2644                                 'page_touched'   => $now,
2645                                 'page_namespace' => $nt->getNamespace(),
2646                                 'page_title'     => $nt->getDBkey(),
2647                                 'page_latest'    => $nullRevId,
2648                         ),
2649                         /* WHERE */ array( 'page_id' => $oldid ),
2650                         $fname
2651                 );
2652                 $nt->resetArticleID( $oldid );
2653
2654                 if($createRedirect || !$wgUser->isAllowed('suppressredirect'))
2655                 {
2656                         # Insert redirect
2657                         $mwRedir = MagicWord::get( 'redirect' );
2658                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
2659                         $redirectArticle = new Article( $this );
2660                         $newid = $redirectArticle->insertOn( $dbw );
2661                         $redirectRevision = new Revision( array(
2662                                 'page'    => $newid,
2663                                 'comment' => $comment,
2664                                 'text'    => $redirectText ) );
2665                         $redirectRevision->insertOn( $dbw );
2666                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
2667
2668                         # Record the just-created redirect's linking to the page
2669                         $dbw->insert( 'pagelinks',
2670                                 array(
2671                                         'pl_from'      => $newid,
2672                                         'pl_namespace' => $nt->getNamespace(),
2673                                         'pl_title'     => $nt->getDBkey() ),
2674                                 $fname );
2675                 } else {
2676                         $this->resetArticleID( 0 );
2677                 }
2678
2679                 # Log the move
2680                 $log = new LogPage( 'move' );
2681                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText()) );
2682
2683                 # Purge caches as per article creation
2684                 Article::onArticleCreate( $nt );
2685
2686                 # Purge old title from squid
2687                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
2688                 $this->purgeSquid();
2689         }
2690
2691         /**
2692          * Checks if $this can be moved to a given Title
2693          * - Selects for update, so don't call it unless you mean business
2694          *
2695          * @param Title &$nt the new title to check
2696          */
2697         public function isValidMoveTarget( $nt ) {
2698
2699                 $fname = 'Title::isValidMoveTarget';
2700                 $dbw = wfGetDB( DB_MASTER );
2701
2702                 # Is it a redirect?
2703                 $id  = $nt->getArticleID();
2704                 $obj = $dbw->selectRow( array( 'page', 'revision', 'text'),
2705                         array( 'page_is_redirect','old_text','old_flags' ),
2706                         array( 'page_id' => $id, 'page_latest=rev_id', 'rev_text_id=old_id' ),
2707                         $fname, 'FOR UPDATE' );
2708
2709                 if ( !$obj || 0 == $obj->page_is_redirect ) {
2710                         # Not a redirect
2711                         wfDebug( __METHOD__ . ": not a redirect\n" );
2712                         return false;
2713                 }
2714                 $text = Revision::getRevisionText( $obj );
2715
2716                 # Does the redirect point to the source?
2717                 # Or is it a broken self-redirect, usually caused by namespace collisions?
2718                 $m = array();
2719                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
2720                         $redirTitle = Title::newFromText( $m[1] );
2721                         if( !is_object( $redirTitle ) ||
2722                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
2723                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
2724                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
2725                                 return false;
2726                         }
2727                 } else {
2728                         # Fail safe
2729                         wfDebug( __METHOD__ . ": failsafe\n" );
2730                         return false;
2731                 }
2732
2733                 # Does the article have a history?
2734                 $row = $dbw->selectRow( array( 'page', 'revision'),
2735                         array( 'rev_id' ),
2736                         array( 'page_namespace' => $nt->getNamespace(),
2737                                 'page_title' => $nt->getDBkey(),
2738                                 'page_id=rev_page AND page_latest != rev_id'
2739                         ), $fname, 'FOR UPDATE'
2740                 );
2741
2742                 # Return true if there was no history
2743                 return $row === false;
2744         }
2745
2746         /**
2747          * Can this title be added to a user's watchlist?
2748          *
2749          * @return bool
2750          */
2751         public function isWatchable() {
2752                 return !$this->isExternal()
2753                         && MWNamespace::isWatchable( $this->getNamespace() );
2754         }
2755
2756         /**
2757          * Get categories to which this Title belongs and return an array of
2758          * categories' names.
2759          *
2760          * @return array an array of parents in the form:
2761          *      $parent => $currentarticle
2762          */
2763         public function getParentCategories() {
2764                 global $wgContLang;
2765
2766                 $titlekey = $this->getArticleId();
2767                 $dbr = wfGetDB( DB_SLAVE );
2768                 $categorylinks = $dbr->tableName( 'categorylinks' );
2769
2770                 # NEW SQL
2771                 $sql = "SELECT * FROM $categorylinks"
2772                      ." WHERE cl_from='$titlekey'"
2773                          ." AND cl_from <> '0'"
2774                          ." ORDER BY cl_sortkey";
2775
2776                 $res = $dbr->query ( $sql ) ;
2777
2778                 if($dbr->numRows($res) > 0) {
2779                         while ( $x = $dbr->fetchObject ( $res ) )
2780                                 //$data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to);
2781                                 $data[$wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to] = $this->getFullText();
2782                         $dbr->freeResult ( $res ) ;
2783                 } else {
2784                         $data = array();
2785                 }
2786                 return $data;
2787         }
2788
2789         /**
2790          * Get a tree of parent categories
2791          * @param array $children an array with the children in the keys, to check for circular refs
2792          * @return array
2793          */
2794         public function getParentCategoryTree( $children = array() ) {
2795                 $stack = array();
2796                 $parents = $this->getParentCategories();
2797
2798                 if($parents != '') {
2799                         foreach($parents as $parent => $current) {
2800                                 if ( array_key_exists( $parent, $children ) ) {
2801                                         # Circular reference
2802                                         $stack[$parent] = array();
2803                                 } else {
2804                                         $nt = Title::newFromText($parent);
2805                                         if ( $nt ) {
2806                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array($parent => 1) );
2807                                         }
2808                                 }
2809                         }
2810                         return $stack;
2811                 } else {
2812                         return array();
2813                 }
2814         }
2815
2816
2817         /**
2818          * Get an associative array for selecting this title from
2819          * the "page" table
2820          *
2821          * @return array
2822          */
2823         public function pageCond() {
2824                 return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
2825         }
2826
2827         /**
2828          * Get the revision ID of the previous revision
2829          *
2830          * @param integer $revision  Revision ID. Get the revision that was before this one.
2831          * @return integer $oldrevision|false
2832          */
2833         public function getPreviousRevisionID( $revision ) {
2834                 $dbr = wfGetDB( DB_SLAVE );
2835                 return $dbr->selectField( 'revision', 'rev_id',
2836                         'rev_page=' . intval( $this->getArticleId() ) .
2837                         ' AND rev_id<' . intval( $revision ) . ' ORDER BY rev_id DESC' );
2838         }
2839
2840         /**
2841          * Get the revision ID of the next revision
2842          *
2843          * @param integer $revision  Revision ID. Get the revision that was after this one.
2844          * @return integer $oldrevision|false
2845          */
2846         public function getNextRevisionID( $revision ) {
2847                 $dbr = wfGetDB( DB_SLAVE );
2848                 return $dbr->selectField( 'revision', 'rev_id',
2849                         'rev_page=' . intval( $this->getArticleId() ) .
2850                         ' AND rev_id>' . intval( $revision ) . ' ORDER BY rev_id' );
2851         }
2852
2853         /**
2854          * Get the number of revisions between the given revision IDs.
2855          *
2856          * @param integer $old  Revision ID.
2857          * @param integer $new  Revision ID.
2858          * @return integer  Number of revisions between these IDs.
2859          */
2860         public function countRevisionsBetween( $old, $new ) {
2861                 $dbr = wfGetDB( DB_SLAVE );
2862                 return $dbr->selectField( 'revision', 'count(*)',
2863                         'rev_page = ' . intval( $this->getArticleId() ) .
2864                         ' AND rev_id > ' . intval( $old ) .
2865                         ' AND rev_id < ' . intval( $new ),
2866                         __METHOD__ );
2867         }
2868
2869         /**
2870          * Compare with another title.
2871          *
2872          * @param Title $title
2873          * @return bool
2874          */
2875         public function equals( $title ) {
2876                 // Note: === is necessary for proper matching of number-like titles.
2877                 return $this->getInterwiki() === $title->getInterwiki()
2878                         && $this->getNamespace() == $title->getNamespace()
2879                         && $this->getDBkey() === $title->getDBkey();
2880         }
2881
2882         /**
2883          * Return a string representation of this title
2884          *
2885          * @return string
2886          */
2887         public function __toString() {
2888                 return $this->getPrefixedText();
2889         }
2890
2891         /**
2892          * Check if page exists
2893          * @return bool
2894          */
2895         public function exists() {
2896                 return $this->getArticleId() != 0;
2897         }
2898
2899         /**
2900          * Do we know that this title definitely exists, or should we otherwise
2901          * consider that it exists?
2902          *
2903          * @return bool
2904          */
2905         public function isAlwaysKnown() {
2906                 // If the page is form Mediawiki:message/lang, calling wfMsgWeirdKey causes
2907                 // the full l10n of that language to be loaded. That takes much memory and
2908                 // isn't needed. So we strip the language part away.
2909                 // Also, extension messages which are not loaded, are shown as red, because
2910                 // we don't call MessageCache::loadAllMessages.
2911                 list( $basename, /* rest */ ) = explode( '/', $this->mDbkeyform, 2 );
2912                 return $this->isExternal()
2913                         || ( $this->mNamespace == NS_MAIN && $this->mDbkeyform == '' )
2914                         || ( $this->mNamespace == NS_MEDIAWIKI && wfMsgWeirdKey( $basename ) );
2915         }
2916
2917         /**
2918          * Update page_touched timestamps and send squid purge messages for
2919          * pages linking to this title. May be sent to the job queue depending
2920          * on the number of links. Typically called on create and delete.
2921          */
2922         public function touchLinks() {
2923                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
2924                 $u->doUpdate();
2925
2926                 if ( $this->getNamespace() == NS_CATEGORY ) {
2927                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
2928                         $u->doUpdate();
2929                 }
2930         }
2931
2932         /**
2933          * Get the last touched timestamp
2934          */
2935         public function getTouched() {
2936                 $dbr = wfGetDB( DB_SLAVE );
2937                 $touched = $dbr->selectField( 'page', 'page_touched',
2938                         array(
2939                                 'page_namespace' => $this->getNamespace(),
2940                                 'page_title' => $this->getDBkey()
2941                         ), __METHOD__
2942                 );
2943                 return $touched;
2944         }
2945
2946         public function trackbackURL() {
2947                 global $wgTitle, $wgScriptPath, $wgServer;
2948
2949                 return "$wgServer$wgScriptPath/trackback.php?article="
2950                         . htmlspecialchars(urlencode($wgTitle->getPrefixedDBkey()));
2951         }
2952
2953         public function trackbackRDF() {
2954                 $url = htmlspecialchars($this->getFullURL());
2955                 $title = htmlspecialchars($this->getText());
2956                 $tburl = $this->trackbackURL();
2957
2958                 // Autodiscovery RDF is placed in comments so HTML validator
2959                 // won't barf. This is a rather icky workaround, but seems
2960                 // frequently used by this kind of RDF thingy.
2961                 //
2962                 // Spec: http://www.sixapart.com/pronet/docs/trackback_spec
2963                 return "<!--
2964 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
2965          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
2966          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
2967 <rdf:Description
2968    rdf:about=\"$url\"
2969    dc:identifier=\"$url\"
2970    dc:title=\"$title\"
2971    trackback:ping=\"$tburl\" />
2972 </rdf:RDF>
2973 -->";
2974         }
2975
2976         /**
2977          * Generate strings used for xml 'id' names in monobook tabs
2978          * @return string
2979          */
2980         public function getNamespaceKey() {
2981                 global $wgContLang;
2982                 switch ($this->getNamespace()) {
2983                         case NS_MAIN:
2984                         case NS_TALK:
2985                                 return 'nstab-main';
2986                         case NS_USER:
2987                         case NS_USER_TALK:
2988                                 return 'nstab-user';
2989                         case NS_MEDIA:
2990                                 return 'nstab-media';
2991                         case NS_SPECIAL:
2992                                 return 'nstab-special';
2993                         case NS_PROJECT:
2994                         case NS_PROJECT_TALK:
2995                                 return 'nstab-project';
2996                         case NS_IMAGE:
2997                         case NS_IMAGE_TALK:
2998                                 return 'nstab-image';
2999                         case NS_MEDIAWIKI:
3000                         case NS_MEDIAWIKI_TALK:
3001                                 return 'nstab-mediawiki';
3002                         case NS_TEMPLATE:
3003                         case NS_TEMPLATE_TALK:
3004                                 return 'nstab-template';
3005                         case NS_HELP:
3006                         case NS_HELP_TALK:
3007                                 return 'nstab-help';
3008                         case NS_CATEGORY:
3009                         case NS_CATEGORY_TALK:
3010                                 return 'nstab-category';
3011                         default:
3012                                 return 'nstab-' . $wgContLang->lc( $this->getSubjectNsText() );
3013                 }
3014         }
3015
3016         /**
3017          * Returns true if this title resolves to the named special page
3018          * @param string $name The special page name
3019          */
3020         public function isSpecial( $name ) {
3021                 if ( $this->getNamespace() == NS_SPECIAL ) {
3022                         list( $thisName, /* $subpage */ ) = SpecialPage::resolveAliasWithSubpage( $this->getDBkey() );
3023                         if ( $name == $thisName ) {
3024                                 return true;
3025                         }
3026                 }
3027                 return false;
3028         }
3029
3030         /**
3031          * If the Title refers to a special page alias which is not the local default,
3032          * returns a new Title which points to the local default. Otherwise, returns $this.
3033          */
3034         public function fixSpecialName() {
3035                 if ( $this->getNamespace() == NS_SPECIAL ) {
3036                         $canonicalName = SpecialPage::resolveAlias( $this->mDbkeyform );
3037                         if ( $canonicalName ) {
3038                                 $localName = SpecialPage::getLocalNameFor( $canonicalName );
3039                                 if ( $localName != $this->mDbkeyform ) {
3040                                         return Title::makeTitle( NS_SPECIAL, $localName );
3041                                 }
3042                         }
3043                 }
3044                 return $this;
3045         }
3046
3047         /**
3048          * Is this Title in a namespace which contains content?
3049          * In other words, is this a content page, for the purposes of calculating
3050          * statistics, etc?
3051          *
3052          * @return bool
3053          */
3054         public function isContentPage() {
3055                 return MWNamespace::isContent( $this->getNamespace() );
3056         }
3057
3058 }