includes/Title.php

   1 <?php
   2 /**
   3  * See title.txt
   4  * @file
   5  */
   6
   7 if ( !class_exists( 'UtfNormal' ) ) {
   8         require_once( dirname(__FILE__) . '/normal/UtfNormal.php' );
   9 }
  10
  11 define ( 'GAID_FOR_UPDATE', 1 );
  12
  13 /**
  14  * Title::newFromText maintains a cache to avoid expensive re-normalization of
  15  * commonly used titles. On a batch operation this can become a memory leak
  16  * if not bounded. After hitting this many titles reset the cache.
  17  */
  18 define( 'MW_TITLECACHE_MAX', 1000 );
  19
  20 /**
  21  * Constants for pr_cascade bitfield
  22  */
  23 define( 'CASCADE', 1 );
  24
  25 /**
  26  * Title class
  27  * - Represents a title, which may contain an interwiki designation or namespace
  28  * - Can fetch various kinds of data from the database, albeit inefficiently.
  29  *
  30  */
  31 class Title {
  32         /**
  33          * Static cache variables
  34          */
  35         static private $titleCache=array();
  36         static private $interwikiCache=array();
  37
  38
  39         /**
  40          * All member variables should be considered private
  41          * Please use the accessor functions
  42          */
  43
  44         /**#@+
  45          * @private
  46          */
  47
  48         var $mTextform = '';              # Text form (spaces not underscores) of the main part
  49         var $mUrlform = '';               # URL-encoded form of the main part
  50         var $mDbkeyform = '';             # Main part with underscores
  51         var $mUserCaseDBKey;              # DB key with the initial letter in the case specified by the user
  52         var $mNamespace = NS_MAIN;        # Namespace index, i.e. one of the NS_xxxx constants
  53         var $mInterwiki = '';             # Interwiki prefix (or null string)
  54         var $mFragment;                       # Title fragment (i.e. the bit after the #)
  55         var $mArticleID = -1;             # Article ID, fetched from the link cache on demand
  56         var $mLatestID = false;           # ID of most recent revision
  57         var $mRestrictions = array();     # Array of groups allowed to edit this article
  58         var $mOldRestrictions = false;
  59         var $mCascadeRestriction;             # Cascade restrictions on this page to included templates and images?
  60         var $mRestrictionsExpiry;             # When do the restrictions on this page expire?
  61         var $mHasCascadingRestrictions;   # Are cascading restrictions in effect on this page?
  62         var $mCascadeRestrictionSources;  # Where are the cascading restrictions coming from on this page?
  63         var $mRestrictionsLoaded = false; # Boolean for initialisation on demand
  64         var $mPrefixedText;                   # Text form including namespace/interwiki, initialised on demand
  65         # Don't change the following default, NS_MAIN is hardcoded in several
  66         # places.  See bug 696.
  67         var $mDefaultNamespace = NS_MAIN; # Namespace index when there is no namespace
  68                                               # Zero except in {{transclusion}} tags
  69         var $mWatched = null;                     # Is $wgUser watching this page? null if unfilled, accessed through userIsWatching()
  70         var $mLength = -1;                # The page length, 0 for special pages
  71         var $mRedirect = null;            # Is the article at this title a redirect?
  72         /**#@-*/
  73
  74
  75         /**
  76          * Constructor
  77          * @private
  78          */
  79         /* private */ function __construct() {}
  80
  81         /**
  82          * Create a new Title from a prefixed DB key
  83          * @param string $key The database key, which has underscores
  84          *      instead of spaces, possibly including namespace and
  85          *      interwiki prefixes
  86          * @return Title the new object, or NULL on an error
  87          */
  88         public static function newFromDBkey( $key ) {
  89                 $t = new Title();
  90                 $t->mDbkeyform = $key;
  91                 if( $t->secureAndSplit() )
  92                         return $t;
  93                 else
  94                         return NULL;
  95         }
  96
  97         /**
  98          * Create a new Title from text, such as what one would
  99          * find in a link. Decodes any HTML entities in the text.
 100          *
 101          * @param string $text the link text; spaces, prefixes,
 102          *      and an initial ':' indicating the main namespace
 103          *      are accepted
 104          * @param int $defaultNamespace the namespace to use if
 105          *      none is specified by a prefix
 106          * @return Title the new object, or NULL on an error
 107          */
 108         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 109                 if( is_object( $text ) ) {
 110                         throw new MWException( 'Title::newFromText given an object' );
 111                 }
 112
 113                 /**
 114                  * Wiki pages often contain multiple links to the same page.
 115                  * Title normalization and parsing can become expensive on
 116                  * pages with many links, so we can save a little time by
 117                  * caching them.
 118                  *
 119                  * In theory these are value objects and won't get changed...
 120                  */
 121                 if( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 122                         return Title::$titleCache[$text];
 123                 }
 124
 125                 /**
 126                  * Convert things like &eacute; &#257; or &#x3017; into real text...
 127                  */
 128                 $filteredText = Sanitizer::decodeCharReferences( $text );
 129
 130                 $t = new Title();
 131                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 132                 $t->mDefaultNamespace = $defaultNamespace;
 133
 134                 static $cachedcount = 0 ;
 135                 if( $t->secureAndSplit() ) {
 136                         if( $defaultNamespace == NS_MAIN ) {
 137                                 if( $cachedcount >= MW_TITLECACHE_MAX ) {
 138                                         # Avoid memory leaks on mass operations...
 139                                         Title::$titleCache = array();
 140                                         $cachedcount=0;
 141                                 }
 142                                 $cachedcount++;
 143                                 Title::$titleCache[$text] =& $t;
 144                         }
 145                         return $t;
 146                 } else {
 147                         $ret = NULL;
 148                         return $ret;
 149                 }
 150         }
 151
 152         /**
 153          * Create a new Title from URL-encoded text. Ensures that
 154          * the given title's length does not exceed the maximum.
 155          * @param string $url the title, as might be taken from a URL
 156          * @return Title the new object, or NULL on an error
 157          */
 158         public static function newFromURL( $url ) {
 159                 global $wgLegalTitleChars;
 160                 $t = new Title();
 161
 162                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 163                 # but some URLs used it as a space replacement and they still come
 164                 # from some external search tools.
 165                 if ( strpos( $wgLegalTitleChars, '+' ) === false ) {
 166                         $url = str_replace( '+', ' ', $url );
 167                 }
 168
 169                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 170                 if( $t->secureAndSplit() ) {
 171                         return $t;
 172                 } else {
 173                         return NULL;
 174                 }
 175         }
 176
 177         /**
 178          * Create a new Title from an article ID
 179          *
 180          * @todo This is inefficiently implemented, the page row is requested
 181          *       but not used for anything else
 182          *
 183          * @param int $id the page_id corresponding to the Title to create
 184          * @param int $flags, use GAID_FOR_UPDATE to use master
 185          * @return Title the new object, or NULL on an error
 186          */
 187         public static function newFromID( $id, $flags = 0 ) {
 188                 $fname = 'Title::newFromID';
 189                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
 190                 $row = $db->selectRow( 'page', array( 'page_namespace', 'page_title' ),
 191                         array( 'page_id' => $id ), $fname );
 192                 if ( $row !== false ) {
 193                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 194                 } else {
 195                         $title = NULL;
 196                 }
 197                 return $title;
 198         }
 199
 200         /**
 201          * Make an array of titles from an array of IDs
 202          */
 203         public static function newFromIDs( $ids ) {
 204                 if ( !count( $ids ) ) {
 205                         return array();
 206                 }
 207                 $dbr = wfGetDB( DB_SLAVE );
 208                 $res = $dbr->select( 'page', array( 'page_namespace', 'page_title' ),
 209                         'page_id IN (' . $dbr->makeList( $ids ) . ')', __METHOD__ );
 210
 211                 $titles = array();
 212                 foreach( $res as $row ) {
 213                         $titles[] = Title::makeTitle( $row->page_namespace, $row->page_title );
 214                 }
 215                 return $titles;
 216         }
 217
 218         /**
 219          * Make a Title object from a DB row
 220          * @param Row $row (needs at least page_title,page_namespace)
 221          */
 222         public static function newFromRow( $row ) {
 223                 $t = self::makeTitle( $row->page_namespace, $row->page_title );
 224
 225                 $t->mArticleID = isset($row->page_id) ? intval($row->page_id) : -1;
 226                 $t->mLength = isset($row->page_len) ? intval($row->page_len) : -1;
 227                 $t->mRedirect = isset($row->page_is_redirect) ? (bool)$row->page_is_redirect : NULL;
 228                 $t->mLatestID = isset($row->page_latest) ? $row->page_latest : false;
 229
 230                 return $t;
 231         }
 232
 233         /**
 234          * Create a new Title from a namespace index and a DB key.
 235          * It's assumed that $ns and $title are *valid*, for instance when
 236          * they came directly from the database or a special page name.
 237          * For convenience, spaces are converted to underscores so that
 238          * eg user_text fields can be used directly.
 239          *
 240          * @param int $ns the namespace of the article
 241          * @param string $title the unprefixed database key form
 242          * @param string $fragment The link fragment (after the "#")
 243          * @return Title the new object
 244          */
 245         public static function &makeTitle( $ns, $title, $fragment = '' ) {
 246                 $t = new Title();
 247                 $t->mInterwiki = '';
 248                 $t->mFragment = $fragment;
 249                 $t->mNamespace = $ns = intval( $ns );
 250                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 251                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 252                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 253                 $t->mTextform = str_replace( '_', ' ', $title );
 254                 return $t;
 255         }
 256
 257         /**
 258          * Create a new Title from a namespace index and a DB key.
 259          * The parameters will be checked for validity, which is a bit slower
 260          * than makeTitle() but safer for user-provided data.
 261          *
 262          * @param int $ns the namespace of the article
 263          * @param string $title the database key form
 264          * @param string $fragment The link fragment (after the "#")
 265          * @return Title the new object, or NULL on an error
 266          */
 267         public static function makeTitleSafe( $ns, $title, $fragment = '' ) {
 268                 $t = new Title();
 269                 $t->mDbkeyform = Title::makeName( $ns, $title, $fragment );
 270                 if( $t->secureAndSplit() ) {
 271                         return $t;
 272                 } else {
 273                         return NULL;
 274                 }
 275         }
 276
 277         /**
 278          * Create a new Title for the Main Page
 279          * @return Title the new object
 280          */
 281         public static function newMainPage() {
 282                 $title = Title::newFromText( wfMsgForContent( 'mainpage' ) );
 283                 // Don't give fatal errors if the message is broken
 284                 if ( !$title ) {
 285                         $title = Title::newFromText( 'Main Page' );
 286                 }
 287                 return $title;
 288         }
 289
 290         /**
 291          * Extract a redirect destination from a string and return the
 292          * Title, or null if the text doesn't contain a valid redirect
 293          *
 294          * @param string $text Text with possible redirect
 295          * @return Title
 296          */
 297         public static function newFromRedirect( $text ) {
 298                 $redir = MagicWord::get( 'redirect' );
 299                 if( $redir->matchStart( trim($text) ) ) {
 300                         // Extract the first link and see if it's usable
 301                         $m = array();
 302                         if( preg_match( '!\[{2}(.*?)(?:\|.*?)?\]{2}!', $text, $m ) ) {
 303                                 // Strip preceding colon used to "escape" categories, etc.
 304                                 // and URL-decode links
 305                                 if( strpos( $m[1], '%' ) !== false ) {
 306                                         // Match behavior of inline link parsing here;
 307                                         // don't interpret + as " " most of the time!
 308                                         // It might be safe to just use rawurldecode instead, though.
 309                                         $m[1] = urldecode( ltrim( $m[1], ':' ) );
 310                                 }
 311                                 $title = Title::newFromText( $m[1] );
 312                                 // Redirects to Special:Userlogout are not permitted
 313                                 if( $title instanceof Title && !$title->isSpecial( 'Userlogout' ) )
 314                                         return $title;
 315                         }
 316                 }
 317                 return null;
 318         }
 319
 320 #----------------------------------------------------------------------------
 321 #       Static functions
 322 #----------------------------------------------------------------------------
 323
 324         /**
 325          * Get the prefixed DB key associated with an ID
 326          * @param int $id the page_id of the article
 327          * @return Title an object representing the article, or NULL
 328          *      if no such article was found
 329          */
 330         public static function nameOf( $id ) {
 331                 $dbr = wfGetDB( DB_SLAVE );
 332
 333                 $s = $dbr->selectRow( 'page', array( 'page_namespace','page_title' ),  array( 'page_id' => $id ), __METHOD__ );
 334                 if ( $s === false ) { return NULL; }
 335
 336                 $n = self::makeName( $s->page_namespace, $s->page_title );
 337                 return $n;
 338         }
 339
 340         /**
 341          * Get a regex character class describing the legal characters in a link
 342          * @return string the list of characters, not delimited
 343          */
 344         public static function legalChars() {
 345                 global $wgLegalTitleChars;
 346                 return $wgLegalTitleChars;
 347         }
 348
 349         /**
 350          * Get a string representation of a title suitable for
 351          * including in a search index
 352          *
 353          * @param int $ns a namespace index
 354          * @param string $title text-form main part
 355          * @return string a stripped-down title string ready for the
 356          *      search index
 357          */
 358         public static function indexTitle( $ns, $title ) {
 359                 global $wgContLang;
 360
 361                 $lc = SearchEngine::legalSearchChars() . '&#;';
 362                 $t = $wgContLang->stripForSearch( $title );
 363                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 364                 $t = $wgContLang->lc( $t );
 365
 366                 # Handle 's, s'
 367                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 368                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 369
 370                 $t = preg_replace( "/\\s+/", ' ', $t );
 371
 372                 if ( $ns == NS_IMAGE ) {
 373                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 374                 }
 375                 return trim( $t );
 376         }
 377
 378         /*
 379          * Make a prefixed DB key from a DB key and a namespace index
 380          * @param int $ns numerical representation of the namespace
 381          * @param string $title the DB key form the title
 382          * @param string $fragment The link fragment (after the "#")
 383          * @return string the prefixed form of the title
 384          */
 385         public static function makeName( $ns, $title, $fragment = '' ) {
 386                 global $wgContLang;
 387
 388                 $namespace = $wgContLang->getNsText( $ns );
 389                 $name = $namespace == '' ? $title : "$namespace:$title";
 390                 if ( strval( $fragment ) != '' ) {
 391                         $name .= '#' . $fragment;
 392                 }
 393                 return $name;
 394         }
 395
 396         /**
 397          * Returns the URL associated with an interwiki prefix
 398          * @param string $key the interwiki prefix (e.g. "MeatBall")
 399          * @return the associated URL, containing "$1", which should be
 400          *      replaced by an article title
 401          * @static (arguably)
 402          */
 403         public function getInterwikiLink( $key )  {
 404                 global $wgMemc, $wgInterwikiExpiry;
 405                 global $wgInterwikiCache, $wgContLang;
 406                 $fname = 'Title::getInterwikiLink';
 407
 408                 $key = $wgContLang->lc( $key );
 409
 410                 $k = wfMemcKey( 'interwiki', $key );
 411                 if( array_key_exists( $k, Title::$interwikiCache ) ) {
 412                         return Title::$interwikiCache[$k]->iw_url;
 413                 }
 414
 415                 if ($wgInterwikiCache) {
 416                         return Title::getInterwikiCached( $key );
 417                 }
 418
 419                 $s = $wgMemc->get( $k );
 420                 # Ignore old keys with no iw_local
 421                 if( $s && isset( $s->iw_local ) && isset($s->iw_trans)) {
 422                         Title::$interwikiCache[$k] = $s;
 423                         return $s->iw_url;
 424                 }
 425
 426                 $dbr = wfGetDB( DB_SLAVE );
 427                 $res = $dbr->select( 'interwiki',
 428                         array( 'iw_url', 'iw_local', 'iw_trans' ),
 429                         array( 'iw_prefix' => $key ), $fname );
 430                 if( !$res ) {
 431                         return '';
 432                 }
 433
 434                 $s = $dbr->fetchObject( $res );
 435                 if( !$s ) {
 436                         # Cache non-existence: create a blank object and save it to memcached
 437                         $s = (object)false;
 438                         $s->iw_url = '';
 439                         $s->iw_local = 0;
 440                         $s->iw_trans = 0;
 441                 }
 442                 $wgMemc->set( $k, $s, $wgInterwikiExpiry );
 443                 Title::$interwikiCache[$k] = $s;
 444
 445                 return $s->iw_url;
 446         }
 447
 448         /**
 449          * Fetch interwiki prefix data from local cache in constant database
 450          *
 451          * More logic is explained in DefaultSettings
 452          *
 453          * @return string URL of interwiki site
 454          */
 455         public static function getInterwikiCached( $key ) {
 456                 global $wgInterwikiCache, $wgInterwikiScopes, $wgInterwikiFallbackSite;
 457                 static $db, $site;
 458
 459                 if (!$db)
 460                         $db=dba_open($wgInterwikiCache,'r','cdb');
 461                 /* Resolve site name */
 462                 if ($wgInterwikiScopes>=3 and !$site) {
 463                         $site = dba_fetch('__sites:' . wfWikiID(), $db);
 464                         if ($site=="")
 465                                 $site = $wgInterwikiFallbackSite;
 466                 }
 467                 $value = dba_fetch( wfMemcKey( $key ), $db);
 468                 if ($value=='' and $wgInterwikiScopes>=3) {
 469                         /* try site-level */
 470                         $value = dba_fetch("_{$site}:{$key}", $db);
 471                 }
 472                 if ($value=='' and $wgInterwikiScopes>=2) {
 473                         /* try globals */
 474                         $value = dba_fetch("__global:{$key}", $db);
 475                 }
 476                 if ($value=='undef')
 477                         $value='';
 478                 $s = (object)false;
 479                 $s->iw_url = '';
 480                 $s->iw_local = 0;
 481                 $s->iw_trans = 0;
 482                 if ($value!='') {
 483                         list($local,$url)=explode(' ',$value,2);
 484                         $s->iw_url=$url;
 485                         $s->iw_local=(int)$local;
 486                 }
 487                 Title::$interwikiCache[wfMemcKey( 'interwiki', $key )] = $s;
 488                 return $s->iw_url;
 489         }
 490         /**
 491          * Determine whether the object refers to a page within
 492          * this project.
 493          *
 494          * @return bool TRUE if this is an in-project interwiki link
 495          *      or a wikilink, FALSE otherwise
 496          */
 497         public function isLocal() {
 498                 if ( $this->mInterwiki != '' ) {
 499                         # Make sure key is loaded into cache
 500                         $this->getInterwikiLink( $this->mInterwiki );
 501                         $k = wfMemcKey( 'interwiki', $this->mInterwiki );
 502                         return (bool)(Title::$interwikiCache[$k]->iw_local);
 503                 } else {
 504                         return true;
 505                 }
 506         }
 507
 508         /**
 509          * Determine whether the object refers to a page within
 510          * this project and is transcludable.
 511          *
 512          * @return bool TRUE if this is transcludable
 513          */
 514         public function isTrans() {
 515                 if ($this->mInterwiki == '')
 516                         return false;
 517                 # Make sure key is loaded into cache
 518                 $this->getInterwikiLink( $this->mInterwiki );
 519                 $k = wfMemcKey( 'interwiki', $this->mInterwiki );
 520                 return (bool)(Title::$interwikiCache[$k]->iw_trans);
 521         }
 522
 523         /**
 524          * Escape a text fragment, say from a link, for a URL
 525          */
 526         static function escapeFragmentForURL( $fragment ) {
 527                 $fragment = str_replace( ' ', '_', $fragment );
 528                 $fragment = urlencode( Sanitizer::decodeCharReferences( $fragment ) );
 529                 $replaceArray = array(
 530                         '%3A' => ':',
 531                         '%' => '.'
 532                 );
 533                 return strtr( $fragment, $replaceArray );
 534         }
 535
 536 #----------------------------------------------------------------------------
 537 #       Other stuff
 538 #----------------------------------------------------------------------------
 539
 540         /** Simple accessors */
 541         /**
 542          * Get the text form (spaces not underscores) of the main part
 543          * @return string
 544          */
 545         public function getText() { return $this->mTextform; }
 546         /**
 547          * Get the URL-encoded form of the main part
 548          * @return string
 549          */
 550         public function getPartialURL() { return $this->mUrlform; }
 551         /**
 552          * Get the main part with underscores
 553          * @return string
 554          */
 555         public function getDBkey() { return $this->mDbkeyform; }
 556         /**
 557          * Get the namespace index, i.e. one of the NS_xxxx constants
 558          * @return int
 559          */
 560         public function getNamespace() { return $this->mNamespace; }
 561         /**
 562          * Get the namespace text
 563          * @return string
 564          */
 565         public function getNsText() {
 566                 global $wgContLang, $wgCanonicalNamespaceNames;
 567
 568                 if ( '' != $this->mInterwiki ) {
 569                         // This probably shouldn't even happen. ohh man, oh yuck.
 570                         // But for interwiki transclusion it sometimes does.
 571                         // Shit. Shit shit shit.
 572                         //
 573                         // Use the canonical namespaces if possible to try to
 574                         // resolve a foreign namespace.
 575                         if( isset( $wgCanonicalNamespaceNames[$this->mNamespace] ) ) {
 576                                 return $wgCanonicalNamespaceNames[$this->mNamespace];
 577                         }
 578                 }
 579                 return $wgContLang->getNsText( $this->mNamespace );
 580         }
 581         /**
 582          * Get the DB key with the initial letter case as specified by the user
 583          */
 584         function getUserCaseDBKey() {
 585                 return $this->mUserCaseDBKey;
 586         }
 587         /**
 588          * Get the namespace text of the subject (rather than talk) page
 589          * @return string
 590          */
 591         public function getSubjectNsText() {
 592                 global $wgContLang;
 593                 return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
 594         }
 595
 596         /**
 597          * Get the namespace text of the talk page
 598          * @return string
 599          */
 600         public function getTalkNsText() {
 601                 global $wgContLang;
 602                 return( $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) ) );
 603         }
 604
 605         /**
 606          * Could this title have a corresponding talk page?
 607          * @return bool
 608          */
 609         public function canTalk() {
 610                 return( MWNamespace::canTalk( $this->mNamespace ) );
 611         }
 612
 613         /**
 614          * Get the interwiki prefix (or null string)
 615          * @return string
 616          */
 617         public function getInterwiki() { return $this->mInterwiki; }
 618         /**
 619          * Get the Title fragment (i.e. the bit after the #) in text form
 620          * @return string
 621          */
 622         public function getFragment() { return $this->mFragment; }
 623         /**
 624          * Get the fragment in URL form, including the "#" character if there is one
 625          * @return string
 626          */
 627         public function getFragmentForURL() {
 628                 if ( $this->mFragment == '' ) {
 629                         return '';
 630                 } else {
 631                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
 632                 }
 633         }
 634         /**
 635          * Get the default namespace index, for when there is no namespace
 636          * @return int
 637          */
 638         public function getDefaultNamespace() { return $this->mDefaultNamespace; }
 639
 640         /**
 641          * Get title for search index
 642          * @return string a stripped-down title string ready for the
 643          *      search index
 644          */
 645         public function getIndexTitle() {
 646                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 647         }
 648
 649         /**
 650          * Get the prefixed database key form
 651          * @return string the prefixed title, with underscores and
 652          *      any interwiki and namespace prefixes
 653          */
 654         public function getPrefixedDBkey() {
 655                 $s = $this->prefix( $this->mDbkeyform );
 656                 $s = str_replace( ' ', '_', $s );
 657                 return $s;
 658         }
 659
 660         /**
 661          * Get the prefixed title with spaces.
 662          * This is the form usually used for display
 663          * @return string the prefixed title, with spaces
 664          */
 665         public function getPrefixedText() {
 666                 if ( empty( $this->mPrefixedText ) ) { // FIXME: bad usage of empty() ?
 667                         $s = $this->prefix( $this->mTextform );
 668                         $s = str_replace( '_', ' ', $s );
 669                         $this->mPrefixedText = $s;
 670                 }
 671                 return $this->mPrefixedText;
 672         }
 673
 674         /**
 675          * Get the prefixed title with spaces, plus any fragment
 676          * (part beginning with '#')
 677          * @return string the prefixed title, with spaces and
 678          *      the fragment, including '#'
 679          */
 680         public function getFullText() {
 681                 $text = $this->getPrefixedText();
 682                 if( '' != $this->mFragment ) {
 683                         $text .= '#' . $this->mFragment;
 684                 }
 685                 return $text;
 686         }
 687
 688         /**
 689          * Get the base name, i.e. the leftmost parts before the /
 690          * @return string Base name
 691          */
 692         public function getBaseText() {
 693                 if( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
 694                         return $this->getText();
 695                 }
 696
 697                 $parts = explode( '/', $this->getText() );
 698                 # Don't discard the real title if there's no subpage involved
 699                 if( count( $parts ) > 1 )
 700                         unset( $parts[ count( $parts ) - 1 ] );
 701                 return implode( '/', $parts );
 702         }
 703
 704         /**
 705          * Get the lowest-level subpage name, i.e. the rightmost part after /
 706          * @return string Subpage name
 707          */
 708         public function getSubpageText() {
 709                 if( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
 710                         return( $this->mTextform );
 711                 }
 712                 $parts = explode( '/', $this->mTextform );
 713                 return( $parts[ count( $parts ) - 1 ] );
 714         }
 715
 716         /**
 717          * Get a URL-encoded form of the subpage text
 718          * @return string URL-encoded subpage name
 719          */
 720         public function getSubpageUrlForm() {
 721                 $text = $this->getSubpageText();
 722                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
 723                 $text = str_replace( '%28', '(', str_replace( '%29', ')', $text ) ); # Clean up the URL; per below, this might not be safe
 724                 return( $text );
 725         }
 726
 727         /**
 728          * Get a URL-encoded title (not an actual URL) including interwiki
 729          * @return string the URL-encoded form
 730          */
 731         public function getPrefixedURL() {
 732                 $s = $this->prefix( $this->mDbkeyform );
 733                 $s = str_replace( ' ', '_', $s );
 734
 735                 $s = wfUrlencode ( $s ) ;
 736
 737                 # Cleaning up URL to make it look nice -- is this safe?
 738                 $s = str_replace( '%28', '(', $s );
 739                 $s = str_replace( '%29', ')', $s );
 740
 741                 return $s;
 742         }
 743
 744         /**
 745          * Get a real URL referring to this title, with interwiki link and
 746          * fragment
 747          *
 748          * @param array $query an optional query string, not used for interwiki
 749          *   links. Can be specified as an associative array as well, e.g.,
 750          *   array( 'action' => 'edit' ) (keys and values will be URL-escaped).
 751          * @param string $variant language variant of url (for sr, zh..)
 752          * @return string the URL
 753          */
 754         public function getFullURL( $query = '', $variant = false ) {
 755                 global $wgContLang, $wgServer, $wgRequest;
 756
 757                 if( is_array( $query ) ) {
 758                         $query = wfArrayToCGI( $query );
 759                 }
 760
 761                 if ( '' == $this->mInterwiki ) {
 762                         $url = $this->getLocalUrl( $query, $variant );
 763
 764                         // Ugly quick hack to avoid duplicate prefixes (bug 4571 etc)
 765                         // Correct fix would be to move the prepending elsewhere.
 766                         if ($wgRequest->getVal('action') != 'render') {
 767                                 $url = $wgServer . $url;
 768                         }
 769                 } else {
 770                         $baseUrl = $this->getInterwikiLink( $this->mInterwiki );
 771
 772                         $namespace = wfUrlencode( $this->getNsText() );
 773                         if ( '' != $namespace ) {
 774                                 # Can this actually happen? Interwikis shouldn't be parsed.
 775                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
 776                                 $namespace .= ':';
 777                         }
 778                         $url = str_replace( '$1', $namespace . $this->mUrlform, $baseUrl );
 779                         $url = wfAppendQuery( $url, $query );
 780                 }
 781
 782                 # Finally, add the fragment.
 783                 $url .= $this->getFragmentForURL();
 784
 785                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
 786                 return $url;
 787         }
 788
 789         /**
 790          * Get a URL with no fragment or server name.  If this page is generated
 791          * with action=render, $wgServer is prepended.
 792          * @param mixed $query an optional query string; if not specified,
 793          *       $wgArticlePath will be used.  Can be specified as an associative array
 794          *   as well, e.g., array( 'action' => 'edit' ) (keys and values will be
 795          *   URL-escaped).
 796          * @param string $variant language variant of url (for sr, zh..)
 797          * @return string the URL
 798          */
 799         public function getLocalURL( $query = '', $variant = false ) {
 800                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
 801                 global $wgVariantArticlePath, $wgContLang, $wgUser;
 802
 803                 if( is_array( $query ) ) {
 804                         $query = wfArrayToCGI( $query );
 805                 }
 806
 807                 // internal links should point to same variant as current page (only anonymous users)
 808                 if($variant == false && $wgContLang->hasVariants() && !$wgUser->isLoggedIn()){
 809                         $pref = $wgContLang->getPreferredVariant(false);
 810                         if($pref != $wgContLang->getCode())
 811                                 $variant = $pref;
 812                 }
 813
 814                 if ( $this->isExternal() ) {
 815                         $url = $this->getFullURL();
 816                         if ( $query ) {
 817                                 // This is currently only used for edit section links in the
 818                                 // context of interwiki transclusion. In theory we should
 819                                 // append the query to the end of any existing query string,
 820                                 // but interwiki transclusion is already broken in that case.
 821                                 $url .= "?$query";
 822                         }
 823                 } else {
 824                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 825                         if ( $query == '' ) {
 826                                 if( $variant != false && $wgContLang->hasVariants() ) {
 827                                         if( $wgVariantArticlePath == false ) {
 828                                                 $variantArticlePath =  "$wgScript?title=$1&variant=$2"; // default
 829                                         } else {
 830                                                 $variantArticlePath = $wgVariantArticlePath;
 831                                         }
 832                                         $url = str_replace( '$2', urlencode( $variant ), $variantArticlePath );
 833                                         $url = str_replace( '$1', $dbkey, $url  );
 834                                 } else {
 835                                         $url = str_replace( '$1', $dbkey, $wgArticlePath );
 836                                 }
 837                         } else {
 838                                 global $wgActionPaths;
 839                                 $url = false;
 840                                 $matches = array();
 841                                 if( !empty( $wgActionPaths ) &&
 842                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
 843                                 {
 844                                         $action = urldecode( $matches[2] );
 845                                         if( isset( $wgActionPaths[$action] ) ) {
 846                                                 $query = $matches[1];
 847                                                 if( isset( $matches[4] ) ) $query .= $matches[4];
 848                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
 849                                                 if( $query != '' ) $url .= '?' . $query;
 850                                         }
 851                                 }
 852                                 if ( $url === false ) {
 853                                         if ( $query == '-' ) {
 854                                                 $query = '';
 855                                         }
 856                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
 857                                 }
 858                         }
 859
 860                         // FIXME: this causes breakage in various places when we
 861                         // actually expected a local URL and end up with dupe prefixes.
 862                         if ($wgRequest->getVal('action') == 'render') {
 863                                 $url = $wgServer . $url;
 864                         }
 865                 }
 866                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
 867                 return $url;
 868         }
 869
 870         /**
 871          * Get a URL that's the simplest URL that will be valid to link, locally,
 872          * to the current Title.  It includes the fragment, but does not include
 873          * the server unless action=render is used (or the link is external).  If
 874          * there's a fragment but the prefixed text is empty, we just return a link
 875          * to the fragment.
 876          *
 877          * @param array $query An associative array of key => value pairs for the
 878          *   query string.  Keys and values will be escaped.
 879          * @param string $variant Language variant of URL (for sr, zh..).  Ignored
 880          *   for external links.  Default is "false" (same variant as current page,
 881          *   for anonymous users).
 882          * @return string the URL
 883          */
 884         public function getLinkUrl( $query = array(), $variant = false ) {
 885                 if( !is_array( $query ) ) {
 886                         throw new MWException( 'Title::getLinkUrl passed a non-array for '.
 887                         '$query' );
 888                 }
 889                 if( $this->isExternal() ) {
 890                         return $this->getFullURL( $query );
 891                 } elseif( $this->getPrefixedText() === ''
 892                 and $this->getFragment() !== '' ) {
 893                         return $this->getFragmentForURL();
 894                 } else {
 895                         return $this->getLocalURL( $query, $variant )
 896                                 . $this->getFragmentForURL();
 897                 }
 898         }
 899
 900         /**
 901          * Get an HTML-escaped version of the URL form, suitable for
 902          * using in a link, without a server name or fragment
 903          * @param string $query an optional query string
 904          * @return string the URL
 905          */
 906         public function escapeLocalURL( $query = '' ) {
 907                 return htmlspecialchars( $this->getLocalURL( $query ) );
 908         }
 909
 910         /**
 911          * Get an HTML-escaped version of the URL form, suitable for
 912          * using in a link, including the server name and fragment
 913          *
 914          * @return string the URL
 915          * @param string $query an optional query string
 916          */
 917         public function escapeFullURL( $query = '' ) {
 918                 return htmlspecialchars( $this->getFullURL( $query ) );
 919         }
 920
 921         /**
 922          * Get the URL form for an internal link.
 923          * - Used in various Squid-related code, in case we have a different
 924          * internal hostname for the server from the exposed one.
 925          *
 926          * @param string $query an optional query string
 927          * @param string $variant language variant of url (for sr, zh..)
 928          * @return string the URL
 929          */
 930         public function getInternalURL( $query = '', $variant = false ) {
 931                 global $wgInternalServer;
 932                 $url = $wgInternalServer . $this->getLocalURL( $query, $variant );
 933                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
 934                 return $url;
 935         }
 936
 937         /**
 938          * Get the edit URL for this Title
 939          * @return string the URL, or a null string if this is an
 940          *      interwiki link
 941          */
 942         public function getEditURL() {
 943                 if ( '' != $this->mInterwiki ) { return ''; }
 944                 $s = $this->getLocalURL( 'action=edit' );
 945
 946                 return $s;
 947         }
 948
 949         /**
 950          * Get the HTML-escaped displayable text form.
 951          * Used for the title field in <a> tags.
 952          * @return string the text, including any prefixes
 953          */
 954         public function getEscapedText() {
 955                 return htmlspecialchars( $this->getPrefixedText() );
 956         }
 957
 958         /**
 959          * Is this Title interwiki?
 960          * @return boolean
 961          */
 962         public function isExternal() { return ( '' != $this->mInterwiki ); }
 963
 964         /**
 965          * Is this page "semi-protected" - the *only* protection is autoconfirm?
 966          *
 967          * @param string Action to check (default: edit)
 968          * @return bool
 969          */
 970         public function isSemiProtected( $action = 'edit' ) {
 971                 if( $this->exists() ) {
 972                         $restrictions = $this->getRestrictions( $action );
 973                         if( count( $restrictions ) > 0 ) {
 974                                 foreach( $restrictions as $restriction ) {
 975                                         if( strtolower( $restriction ) != 'autoconfirmed' )
 976                                                 return false;
 977                                 }
 978                         } else {
 979                                 # Not protected
 980                                 return false;
 981                         }
 982                         return true;
 983                 } else {
 984                         # If it doesn't exist, it can't be protected
 985                         return false;
 986                 }
 987         }
 988
 989         /**
 990          * Does the title correspond to a protected article?
 991          * @param string $what the action the page is protected from,
 992          * by default checks move and edit
 993          * @return boolean
 994          */
 995         public function isProtected( $action = '' ) {
 996                 global $wgRestrictionLevels, $wgRestrictionTypes;
 997
 998                 # Special pages have inherent protection
 999                 if( $this->getNamespace() == NS_SPECIAL )
1000                         return true;
1001
1002                 # Check regular protection levels
1003                 foreach( $wgRestrictionTypes as $type ){
1004                         if( $action == $type || $action == '' ) {
1005                                 $r = $this->getRestrictions( $type );
1006                                 foreach( $wgRestrictionLevels as $level ) {
1007                                         if( in_array( $level, $r ) && $level != '' ) {
1008                                                 return true;
1009                                         }
1010                                 }
1011                         }
1012                 }
1013
1014                 return false;
1015         }
1016
1017         /**
1018          * Is $wgUser watching this page?
1019          * @return boolean
1020          */
1021         public function userIsWatching() {
1022                 global $wgUser;
1023
1024                 if ( is_null( $this->mWatched ) ) {
1025                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn()) {
1026                                 $this->mWatched = false;
1027                         } else {
1028                                 $this->mWatched = $wgUser->isWatched( $this );
1029                         }
1030                 }
1031                 return $this->mWatched;
1032         }
1033
1034         /**
1035          * Can $wgUser perform $action on this page?
1036          * This skips potentially expensive cascading permission checks.
1037          *
1038          * Suitable for use for nonessential UI controls in common cases, but
1039          * _not_ for functional access control.
1040          *
1041          * May provide false positives, but should never provide a false negative.
1042          *
1043          * @param string $action action that permission needs to be checked for
1044          * @return boolean
1045          */
1046         public function quickUserCan( $action ) {
1047                 return $this->userCan( $action, false );
1048         }
1049
1050         /**
1051          * Determines if $wgUser is unable to edit this page because it has been protected
1052          * by $wgNamespaceProtection.
1053          *
1054          * @return boolean
1055          */
1056         public function isNamespaceProtected() {
1057                 global $wgNamespaceProtection, $wgUser;
1058                 if( isset( $wgNamespaceProtection[ $this->mNamespace ] ) ) {
1059                         foreach( (array)$wgNamespaceProtection[ $this->mNamespace ] as $right ) {
1060                                 if( $right != '' && !$wgUser->isAllowed( $right ) )
1061                                         return true;
1062                         }
1063                 }
1064                 return false;
1065         }
1066
1067         /**
1068          * Can $wgUser perform $action on this page?
1069          * @param string $action action that permission needs to be checked for
1070          * @param bool $doExpensiveQueries Set this to false to avoid doing unnecessary queries.
1071          * @return boolean
1072          */
1073         public function userCan( $action, $doExpensiveQueries = true ) {
1074                 global $wgUser;
1075                 return ( $this->getUserPermissionsErrorsInternal( $action, $wgUser, $doExpensiveQueries ) === array());
1076         }
1077
1078         /**
1079          * Can $user perform $action on this page?
1080          *
1081          * FIXME: This *does not* check throttles (User::pingLimiter()).
1082          *
1083          * @param string $action action that permission needs to be checked for
1084          * @param User $user user to check
1085          * @param bool $doExpensiveQueries Set this to false to avoid doing unnecessary queries.
1086          * @param array $ignoreErrors Set this to a list of message keys whose corresponding errors may be ignored.
1087          * @return array Array of arrays of the arguments to wfMsg to explain permissions problems.
1088          */
1089         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1090                 if( !StubObject::isRealObject( $user ) ) {
1091                         //Since StubObject is always used on globals, we can unstub $wgUser here and set $user = $wgUser
1092                         global $wgUser;
1093                         $wgUser->_unstub( '', 5 );
1094                         $user = $wgUser;
1095                 }
1096                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1097
1098                 global $wgContLang;
1099                 global $wgLang;
1100                 global $wgEmailConfirmToEdit;
1101
1102                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() && $action != 'createaccount' ) {
1103                         $errors[] = array( 'confirmedittext' );
1104                 }
1105
1106                 if ( $user->isBlockedFrom( $this ) && $action != 'createaccount' ) {
1107                         $block = $user->mBlock;
1108
1109                         // This is from OutputPage::blockedPage
1110                         // Copied at r23888 by werdna
1111
1112                         $id = $user->blockedBy();
1113                         $reason = $user->blockedFor();
1114                         if( $reason == '' ) {
1115                                 $reason = wfMsg( 'blockednoreason' );
1116                         }
1117                         $ip = wfGetIP();
1118
1119                         if ( is_numeric( $id ) ) {
1120                                 $name = User::whoIs( $id );
1121                         } else {
1122                                 $name = $id;
1123                         }
1124
1125                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1126                         $blockid = $block->mId;
1127                         $blockExpiry = $user->mBlock->mExpiry;
1128                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $user->mBlock->mTimestamp ), true );
1129
1130                         if ( $blockExpiry == 'infinity' ) {
1131                                 // Entry in database (table ipblocks) is 'infinity' but 'ipboptions' uses 'infinite' or 'indefinite'
1132                                 $scBlockExpiryOptions = wfMsg( 'ipboptions' );
1133
1134                                 foreach ( explode( ',', $scBlockExpiryOptions ) as $option ) {
1135                                         if ( strpos( $option, ':' ) == false )
1136                                                 continue;
1137
1138                                         list ($show, $value) = explode( ":", $option );
1139
1140                                         if ( $value == 'infinite' || $value == 'indefinite' ) {
1141                                                 $blockExpiry = $show;
1142                                                 break;
1143                                         }
1144                                 }
1145                         } else {
1146                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1147                         }
1148
1149                         $intended = $user->mBlock->mAddress;
1150
1151                         $errors[] = array( ($block->mAuto ? 'autoblockedtext' : 'blockedtext'), $link, $reason, $ip, $name,
1152                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
1153                 }
1154
1155                 // Remove the errors being ignored.
1156
1157                 foreach( $errors as $index => $error ) {
1158                         $error_key = is_array($error) ? $error[0] : $error;
1159
1160                         if (in_array( $error_key, $ignoreErrors )) {
1161                                 unset($errors[$index]);
1162                         }
1163                 }
1164
1165                 return $errors;
1166         }
1167
1168         /**
1169          * Can $user perform $action on this page? This is an internal function,
1170          * which checks ONLY that previously checked by userCan (i.e. it leaves out
1171          * checks on wfReadOnly() and blocks)
1172          *
1173          * @param string $action action that permission needs to be checked for
1174          * @param User $user user to check
1175          * @param bool $doExpensiveQueries Set this to false to avoid doing unnecessary queries.
1176          * @return array Array of arrays of the arguments to wfMsg to explain permissions problems.
1177          */
1178         private function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true ) {
1179                 wfProfileIn( __METHOD__ );
1180
1181                 $errors = array();
1182
1183                 // Use getUserPermissionsErrors instead
1184                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1185                         wfProfileOut( __METHOD__ );
1186                         return $result ? array() : array( array( 'badaccess-group0' ) );
1187                 }
1188
1189                 if (!wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1190                         if ($result != array() && is_array($result) && !is_array($result[0]))
1191                                 $errors[] = $result; # A single array representing an error
1192                         else if (is_array($result) && is_array($result[0]))
1193                                 $errors = array_merge( $errors, $result ); # A nested array representing multiple errors
1194                         else if ($result != '' && $result != null && $result !== true && $result !== false)
1195                                 $errors[] = array($result); # A string representing a message-id
1196                         else if ($result === false )
1197                                 $errors[] = array('badaccess-group0'); # a generic "We don't want them to do that"
1198                 }
1199                 if ($doExpensiveQueries && !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) ) ) {
1200                         if ($result != array() && is_array($result) && !is_array($result[0]))
1201                                 $errors[] = $result; # A single array representing an error
1202                         else if (is_array($result) && is_array($result[0]))
1203                                 $errors = array_merge( $errors, $result ); # A nested array representing multiple errors
1204                         else if ($result != '' && $result != null && $result !== true && $result !== false)
1205                                 $errors[] = array($result); # A string representing a message-id
1206                         else if ($result === false )
1207                                 $errors[] = array('badaccess-group0'); # a generic "We don't want them to do that"
1208                 }
1209
1210                 $specialOKActions = array( 'createaccount', 'execute' );
1211                 if( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions) ) {
1212                         $errors[] = array('ns-specialprotected');
1213                 }
1214
1215                 if ( $this->isNamespaceProtected() ) {
1216                         $ns = $this->getNamespace() == NS_MAIN
1217                                 ? wfMsg( 'nstab-main' )
1218                                 : $this->getNsText();
1219                         $errors[] = (NS_MEDIAWIKI == $this->mNamespace
1220                                 ? array('protectedinterface')
1221                                 : array( 'namespaceprotected',  $ns ) );
1222                 }
1223
1224                 if( $this->mDbkeyform == '_' ) {
1225                         # FIXME: Is this necessary? Shouldn't be allowed anyway...
1226                         $errors[] = array('badaccess-group0');
1227                 }
1228
1229                 # protect css/js subpages of user pages
1230                 # XXX: this might be better using restrictions
1231                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssJsSubpage() from working
1232                 if( $this->isCssJsSubpage()
1233                         && !$user->isAllowed('editusercssjs')
1234                         && !preg_match('/^'.preg_quote($user->getName(), '/').'\//', $this->mTextform) ) {
1235                         $errors[] = array('customcssjsprotected');
1236                 }
1237
1238                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1239                         # We /could/ use the protection level on the source page, but it's fairly ugly
1240                         #  as we have to establish a precedence hierarchy for pages included by multiple
1241                         #  cascade-protected pages. So just restrict it to people with 'protect' permission,
1242                         #  as they could remove the protection anyway.
1243                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1244                         # Cascading protection depends on more than this page...
1245                         # Several cascading protected pages may include this page...
1246                         # Check each cascading level
1247                         # This is only for protection restrictions, not for all actions
1248                         if( $cascadingSources > 0 && isset($restrictions[$action]) ) {
1249                                 foreach( $restrictions[$action] as $right ) {
1250                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1251                                         if( '' != $right && !$user->isAllowed( $right ) ) {
1252                                                 $pages = '';
1253                                                 foreach( $cascadingSources as $page )
1254                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1255                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1256                                         }
1257                                 }
1258                         }
1259                 }
1260
1261                 foreach( $this->getRestrictions($action) as $right ) {
1262                         // Backwards compatibility, rewrite sysop -> protect
1263                         if ( $right == 'sysop' ) {
1264                                 $right = 'protect';
1265                         }
1266                         if( '' != $right && !$user->isAllowed( $right ) ) {
1267                                 //Users with 'editprotected' permission can edit protected pages
1268                                 if( $action=='edit' && $user->isAllowed( 'editprotected' ) ) {
1269                                         //Users with 'editprotected' permission cannot edit protected pages
1270                                         //with cascading option turned on.
1271                                         if($this->mCascadeRestriction) {
1272                                                 $errors[] = array( 'protectedpagetext', $right );
1273                                         } else {
1274                                                 //Nothing, user can edit!
1275                                         }
1276                                 } else {
1277                                         $errors[] = array( 'protectedpagetext', $right );
1278                                 }
1279                         }
1280                 }
1281
1282                 if ($action == 'protect') {
1283                         if ($this->getUserPermissionsErrors('edit', $user) != array()) {
1284                                 $errors[] = array( 'protect-cantedit' ); // If they can't edit, they shouldn't protect.
1285                         }
1286                 }
1287
1288                 if ($action == 'create') {
1289                         $title_protection = $this->getTitleProtection();
1290
1291                         if (is_array($title_protection)) {
1292                                 extract($title_protection);
1293
1294                                 if ($pt_create_perm == 'sysop')
1295                                         $pt_create_perm = 'protect';
1296
1297                                 if ($pt_create_perm == '' || !$user->isAllowed($pt_create_perm)) {
1298                                         $errors[] = array ( 'titleprotected', User::whoIs($pt_user), $pt_reason );
1299                                 }
1300                         }
1301
1302                         if( (  $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1303                                 ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1304                                 $errors[] = $user->isAnon() ? array ('nocreatetext') : array ('nocreate-loggedin');
1305                         }
1306                 } elseif( $action == 'move' && !( $this->isMovable() && $user->isAllowed( 'move' ) ) ) {
1307                         $errors[] = $user->isAnon() ? array ( 'movenologintext' ) : array ('movenotallowed');
1308                 } elseif ( !$user->isAllowed( $action ) ) {
1309                         $return = null;
1310                         $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
1311                                 User::getGroupsWithPermission( $action ) );
1312                         if ( $groups ) {
1313                                 $return = array( 'badaccess-groups',
1314                                         array(
1315                                                 implode( ', ', $groups ),
1316                                                 count( $groups ) ) );
1317                         }
1318                         else {
1319                                 $return = array( "badaccess-group0" );
1320                         }
1321                         $errors[] = $return;
1322                 }
1323
1324                 wfProfileOut( __METHOD__ );
1325                 return $errors;
1326         }
1327
1328         /**
1329          * Is this title subject to title protection?
1330          * @return mixed An associative array representing any existent title
1331          *   protection, or false if there's none.
1332          */
1333         private function getTitleProtection() {
1334                 // Can't protect pages in special namespaces
1335                 if ( $this->getNamespace() < 0 ) {
1336                         return false;
1337                 }
1338
1339                 $dbr = wfGetDB( DB_SLAVE );
1340                 $res = $dbr->select( 'protected_titles', '*',
1341                         array ('pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey()) );
1342
1343                 if ($row = $dbr->fetchRow( $res )) {
1344                         return $row;
1345                 } else {
1346                         return false;
1347                 }
1348         }
1349
1350         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
1351                 global $wgUser,$wgContLang;
1352
1353                 if ($create_perm == implode(',',$this->getRestrictions('create'))
1354                         && $expiry == $this->mRestrictionsExpiry) {
1355                         // No change
1356                         return true;
1357                 }
1358
1359                 list ($namespace, $title) = array( $this->getNamespace(), $this->getDBkey() );
1360
1361                 $dbw = wfGetDB( DB_MASTER );
1362
1363                 $encodedExpiry = Block::encodeExpiry($expiry, $dbw );
1364
1365                 $expiry_description = '';
1366                 if ( $encodedExpiry != 'infinity' ) {
1367                         $expiry_description = ' (' . wfMsgForContent( 'protect-expiring', $wgContLang->timeanddate( $expiry ) ).')';
1368                 }
1369
1370                 # Update protection table
1371                 if ($create_perm != '' ) {
1372                         $dbw->replace( 'protected_titles', array(array('pt_namespace', 'pt_title')),
1373                                 array( 'pt_namespace' => $namespace, 'pt_title' => $title
1374                                         , 'pt_create_perm' => $create_perm
1375                                         , 'pt_timestamp' => Block::encodeExpiry(wfTimestampNow(), $dbw)
1376                                         , 'pt_expiry' => $encodedExpiry
1377                                         , 'pt_user' => $wgUser->getId(), 'pt_reason' => $reason ), __METHOD__  );
1378                 } else {
1379                         $dbw->delete( 'protected_titles', array( 'pt_namespace' => $namespace,
1380                                 'pt_title' => $title ), __METHOD__ );
1381                 }
1382                 # Update the protection log
1383                 $log = new LogPage( 'protect' );
1384
1385                 if( $create_perm ) {
1386                         $log->addEntry( $this->mRestrictions['create'] ? 'modify' : 'protect', $this, trim( $reason . " [create=$create_perm] $expiry_description" ) );
1387                 } else {
1388                         $log->addEntry( 'unprotect', $this, $reason );
1389                 }
1390
1391                 return true;
1392         }
1393
1394         /**
1395          * Remove any title protection (due to page existing
1396          */
1397         public function deleteTitleProtection() {
1398                 $dbw = wfGetDB( DB_MASTER );
1399
1400                 $dbw->delete( 'protected_titles',
1401                         array ('pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey()), __METHOD__ );
1402         }
1403
1404         /**
1405          * Can $wgUser edit this page?
1406          * @return boolean
1407          * @deprecated use userCan('edit')
1408          */
1409         public function userCanEdit( $doExpensiveQueries = true ) {
1410                 return $this->userCan( 'edit', $doExpensiveQueries );
1411         }
1412
1413         /**
1414          * Can $wgUser create this page?
1415          * @return boolean
1416          * @deprecated use userCan('create')
1417          */
1418         public function userCanCreate( $doExpensiveQueries = true ) {
1419                 return $this->userCan( 'create', $doExpensiveQueries );
1420         }
1421
1422         /**
1423          * Can $wgUser move this page?
1424          * @return boolean
1425          * @deprecated use userCan('move')
1426          */
1427         public function userCanMove( $doExpensiveQueries = true ) {
1428                 return $this->userCan( 'move', $doExpensiveQueries );
1429         }
1430
1431         /**
1432          * Would anybody with sufficient privileges be able to move this page?
1433          * Some pages just aren't movable.
1434          *
1435          * @return boolean
1436          */
1437         public function isMovable() {
1438                 return MWNamespace::isMovable( $this->getNamespace() )
1439                         && $this->getInterwiki() == '';
1440         }
1441
1442         /**
1443          * Can $wgUser read this page?
1444          * @return boolean
1445          * @todo fold these checks into userCan()
1446          */
1447         public function userCanRead() {
1448                 global $wgUser, $wgGroupPermissions;
1449
1450                 $result = null;
1451                 wfRunHooks( 'userCan', array( &$this, &$wgUser, 'read', &$result ) );
1452                 if ( $result !== null ) {
1453                         return $result;
1454                 }
1455
1456                 # Shortcut for public wikis, allows skipping quite a bit of code
1457                 if ($wgGroupPermissions['*']['read'])
1458                         return true;
1459
1460                 if( $wgUser->isAllowed( 'read' ) ) {
1461                         return true;
1462                 } else {
1463                         global $wgWhitelistRead;
1464
1465                         /**
1466                          * Always grant access to the login page.
1467                          * Even anons need to be able to log in.
1468                         */
1469                         if( $this->isSpecial( 'Userlogin' ) || $this->isSpecial( 'Resetpass' ) ) {
1470                                 return true;
1471                         }
1472
1473                         /**
1474                          * Bail out if there isn't whitelist
1475                          */
1476                         if( !is_array($wgWhitelistRead) ) {
1477                                 return false;
1478                         }
1479
1480                         /**
1481                          * Check for explicit whitelisting
1482                          */
1483                         $name = $this->getPrefixedText();
1484                         $dbName = $this->getPrefixedDBKey();
1485                         // Check with and without underscores
1486                         if( in_array($name,$wgWhitelistRead,true) || in_array($dbName,$wgWhitelistRead,true) )
1487                                 return true;
1488
1489                         /**
1490                          * Old settings might have the title prefixed with
1491                          * a colon for main-namespace pages
1492                          */
1493                         if( $this->getNamespace() == NS_MAIN ) {
1494                                 if( in_array( ':' . $name, $wgWhitelistRead ) )
1495                                         return true;
1496                         }
1497
1498                         /**
1499                          * If it's a special page, ditch the subpage bit
1500                          * and check again
1501                          */
1502                         if( $this->getNamespace() == NS_SPECIAL ) {
1503                                 $name = $this->getDBkey();
1504                                 list( $name, /* $subpage */) = SpecialPage::resolveAliasWithSubpage( $name );
1505                                 if ( $name === false ) {
1506                                         # Invalid special page, but we show standard login required message
1507                                         return false;
1508                                 }
1509
1510                                 $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
1511                                 if( in_array( $pure, $wgWhitelistRead, true ) )
1512                                         return true;
1513                         }
1514
1515                 }
1516                 return false;
1517         }
1518
1519         /**
1520          * Is this a talk page of some sort?
1521          * @return bool
1522          */
1523         public function isTalkPage() {
1524                 return MWNamespace::isTalk( $this->getNamespace() );
1525         }
1526
1527         /**
1528          * Is this a subpage?
1529          * @return bool
1530          */
1531         public function isSubpage() {
1532                 return MWNamespace::hasSubpages( $this->mNamespace )
1533                         ? strpos( $this->getText(), '/' ) !== false
1534                         : false;
1535         }
1536
1537         /**
1538          * Does this have subpages?  (Warning, usually requires an extra DB query.)
1539          * @return bool
1540          */
1541         public function hasSubpages() {
1542                 if( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1543                         # Duh
1544                         return false;
1545                 }
1546
1547                 # We dynamically add a member variable for the purpose of this method
1548                 # alone to cache the result.  There's no point in having it hanging
1549                 # around uninitialized in every Title object; therefore we only add it
1550                 # if needed and don't declare it statically.
1551                 if( isset( $this->mHasSubpages ) ) {
1552                         return $this->mHasSubpages;
1553                 }
1554
1555                 $db = wfGetDB( DB_SLAVE );
1556                 return $this->mHasSubpages = (bool)$db->selectField( 'page', '1',
1557                         "page_namespace = {$this->mNamespace} AND page_title LIKE '"
1558                         . $db->escapeLike( $this->mDbkeyform ) . "/%'",
1559                         __METHOD__
1560                 );
1561         }
1562
1563         /**
1564          * Could this page contain custom CSS or JavaScript, based
1565          * on the title?
1566          *
1567          * @return bool
1568          */
1569         public function isCssOrJsPage() {
1570                 return $this->mNamespace == NS_MEDIAWIKI
1571                         && preg_match( '!\.(?:css|js)$!u', $this->mTextform ) > 0;
1572         }
1573
1574         /**
1575          * Is this a .css or .js subpage of a user page?
1576          * @return bool
1577          */
1578         public function isCssJsSubpage() {
1579                 return ( NS_USER == $this->mNamespace and preg_match("/\\/.*\\.(?:css|js)$/", $this->mTextform ) );
1580         }
1581         /**
1582          * Is this a *valid* .css or .js subpage of a user page?
1583          * Check that the corresponding skin exists
1584          */
1585         public function isValidCssJsSubpage() {
1586                 if ( $this->isCssJsSubpage() ) {
1587                         $skinNames = Skin::getSkinNames();
1588                         return array_key_exists( $this->getSkinFromCssJsSubpage(), $skinNames );
1589                 } else {
1590                         return false;
1591                 }
1592         }
1593         /**
1594          * Trim down a .css or .js subpage title to get the corresponding skin name
1595          */
1596         public function getSkinFromCssJsSubpage() {
1597                 $subpage = explode( '/', $this->mTextform );
1598                 $subpage = $subpage[ count( $subpage ) - 1 ];
1599                 return( str_replace( array( '.css', '.js' ), array( '', '' ), $subpage ) );
1600         }
1601         /**
1602          * Is this a .css subpage of a user page?
1603          * @return bool
1604          */
1605         public function isCssSubpage() {
1606                 return ( NS_USER == $this->mNamespace && preg_match("/\\/.*\\.css$/", $this->mTextform ) );
1607         }
1608         /**
1609          * Is this a .js subpage of a user page?
1610          * @return bool
1611          */
1612         public function isJsSubpage() {
1613                 return ( NS_USER == $this->mNamespace && preg_match("/\\/.*\\.js$/", $this->mTextform ) );
1614         }
1615         /**
1616          * Protect css/js subpages of user pages: can $wgUser edit
1617          * this page?
1618          *
1619          * @return boolean
1620          * @todo XXX: this might be better using restrictions
1621          */
1622         public function userCanEditCssJsSubpage() {
1623                 global $wgUser;
1624                 return ( $wgUser->isAllowed('editusercssjs') || preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1625         }
1626
1627         /**
1628          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
1629          *
1630          * @return bool If the page is subject to cascading restrictions.
1631          */
1632         public function isCascadeProtected() {
1633                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
1634                 return ( $sources > 0 );
1635         }
1636
1637         /**
1638          * Cascading protection: Get the source of any cascading restrictions on this page.
1639          *
1640          * @param $get_pages bool Whether or not to retrieve the actual pages that the restrictions have come from.
1641          * @return array( mixed title array, restriction array)
1642          * 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.
1643          * The restriction array is an array of each type, each of which contains an array of unique groups
1644          */
1645         public function getCascadeProtectionSources( $get_pages = true ) {
1646                 global $wgRestrictionTypes;
1647
1648                 # Define our dimension of restrictions types
1649                 $pagerestrictions = array();
1650                 foreach( $wgRestrictionTypes as $action )
1651                         $pagerestrictions[$action] = array();
1652
1653                 if ( isset( $this->mCascadeSources ) && $get_pages ) {
1654                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
1655                 } else if ( isset( $this->mHasCascadingRestrictions ) && !$get_pages ) {
1656                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
1657                 }
1658
1659                 wfProfileIn( __METHOD__ );
1660
1661                 $dbr = wfGetDb( DB_SLAVE );
1662
1663                 if ( $this->getNamespace() == NS_IMAGE ) {
1664                         $tables = array ('imagelinks', 'page_restrictions');
1665                         $where_clauses = array(
1666                                 'il_to' => $this->getDBkey(),
1667                                 'il_from=pr_page',
1668                                 'pr_cascade' => 1 );
1669                 } else {
1670                         $tables = array ('templatelinks', 'page_restrictions');
1671                         $where_clauses = array(
1672                                 'tl_namespace' => $this->getNamespace(),
1673                                 'tl_title' => $this->getDBkey(),
1674                                 'tl_from=pr_page',
1675                                 'pr_cascade' => 1 );
1676                 }
1677
1678                 if ( $get_pages ) {
1679                         $cols = array('pr_page', 'page_namespace', 'page_title', 'pr_expiry', 'pr_type', 'pr_level' );
1680                         $where_clauses[] = 'page_id=pr_page';
1681                         $tables[] = 'page';
1682                 } else {
1683                         $cols = array( 'pr_expiry' );
1684                 }
1685
1686                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
1687
1688                 $sources = $get_pages ? array() : false;
1689                 $now = wfTimestampNow();
1690                 $purgeExpired = false;
1691
1692                 foreach( $res as $row ) {
1693                         $expiry = Block::decodeExpiry( $row->pr_expiry );
1694                         if( $expiry > $now ) {
1695                                 if ($get_pages) {
1696                                         $page_id = $row->pr_page;
1697                                         $page_ns = $row->page_namespace;
1698                                         $page_title = $row->page_title;
1699                                         $sources[$page_id] = Title::makeTitle($page_ns, $page_title);
1700                                         # Add groups needed for each restriction type if its not already there
1701                                         # Make sure this restriction type still exists
1702                                         if ( isset($pagerestrictions[$row->pr_type]) && !in_array($row->pr_level, $pagerestrictions[$row->pr_type]) ) {
1703                                                 $pagerestrictions[$row->pr_type][]=$row->pr_level;
1704                                         }
1705                                 } else {
1706                                         $sources = true;
1707                                 }
1708                         } else {
1709                                 // Trigger lazy purge of expired restrictions from the db
1710                                 $purgeExpired = true;
1711                         }
1712                 }
1713                 if( $purgeExpired ) {
1714                         Title::purgeExpiredRestrictions();
1715                 }
1716
1717                 wfProfileOut( __METHOD__ );
1718
1719                 if ( $get_pages ) {
1720                         $this->mCascadeSources = $sources;
1721                         $this->mCascadingRestrictions = $pagerestrictions;
1722                 } else {
1723                         $this->mHasCascadingRestrictions = $sources;
1724                 }
1725
1726                 return array( $sources, $pagerestrictions );
1727         }
1728
1729         function areRestrictionsCascading() {
1730                 if (!$this->mRestrictionsLoaded) {
1731                         $this->loadRestrictions();
1732                 }
1733
1734                 return $this->mCascadeRestriction;
1735         }
1736
1737         /**
1738          * Loads a string into mRestrictions array
1739          * @param resource $res restrictions as an SQL result.
1740          */
1741         private function loadRestrictionsFromRow( $res, $oldFashionedRestrictions = NULL ) {
1742                 global $wgRestrictionTypes;
1743                 $dbr = wfGetDB( DB_SLAVE );
1744
1745                 foreach( $wgRestrictionTypes as $type ){
1746                         $this->mRestrictions[$type] = array();
1747                 }
1748
1749                 $this->mCascadeRestriction = false;
1750                 $this->mRestrictionsExpiry = Block::decodeExpiry('');
1751
1752                 # Backwards-compatibility: also load the restrictions from the page record (old format).
1753
1754                 if ( $oldFashionedRestrictions === NULL ) {
1755                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
1756                                 array( 'page_id' => $this->getArticleId() ), __METHOD__ );
1757                 }
1758
1759                 if ($oldFashionedRestrictions != '') {
1760
1761                         foreach( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
1762                                 $temp = explode( '=', trim( $restrict ) );
1763                                 if(count($temp) == 1) {
1764                                         // old old format should be treated as edit/move restriction
1765                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
1766                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
1767                                 } else {
1768                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
1769                                 }
1770                         }
1771
1772                         $this->mOldRestrictions = true;
1773
1774                 }
1775
1776                 if( $dbr->numRows( $res ) ) {
1777                         # Current system - load second to make them override.
1778                         $now = wfTimestampNow();
1779                         $purgeExpired = false;
1780
1781                         foreach( $res as $row ) {
1782                                 # Cycle through all the restrictions.
1783
1784                                 // Don't take care of restrictions types that aren't in $wgRestrictionTypes
1785                                 if( !in_array( $row->pr_type, $wgRestrictionTypes ) )
1786                                         continue;
1787
1788                                 // This code should be refactored, now that it's being used more generally,
1789                                 // But I don't really see any harm in leaving it in Block for now -werdna
1790                                 $expiry = Block::decodeExpiry( $row->pr_expiry );
1791
1792                                 // Only apply the restrictions if they haven't expired!
1793                                 if ( !$expiry || $expiry > $now ) {
1794                                         $this->mRestrictionsExpiry = $expiry;
1795                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
1796
1797                                         $this->mCascadeRestriction |= $row->pr_cascade;
1798                                 } else {
1799                                         // Trigger a lazy purge of expired restrictions
1800                                         $purgeExpired = true;
1801                                 }
1802                         }
1803
1804                         if( $purgeExpired ) {
1805                                 Title::purgeExpiredRestrictions();
1806                         }
1807                 }
1808
1809                 $this->mRestrictionsLoaded = true;
1810         }
1811
1812         public function loadRestrictions( $oldFashionedRestrictions = NULL ) {
1813                 if( !$this->mRestrictionsLoaded ) {
1814                         if ($this->exists()) {
1815                                 $dbr = wfGetDB( DB_SLAVE );
1816
1817                                 $res = $dbr->select( 'page_restrictions', '*',
1818                                         array ( 'pr_page' => $this->getArticleId() ), __METHOD__ );
1819
1820                                 $this->loadRestrictionsFromRow( $res, $oldFashionedRestrictions );
1821                         } else {
1822                                 $title_protection = $this->getTitleProtection();
1823
1824                                 if (is_array($title_protection)) {
1825                                         extract($title_protection);
1826
1827                                         $now = wfTimestampNow();
1828                                         $expiry = Block::decodeExpiry($pt_expiry);
1829
1830                                         if (!$expiry || $expiry > $now) {
1831                                                 // Apply the restrictions
1832                                                 $this->mRestrictionsExpiry = $expiry;
1833                                                 $this->mRestrictions['create'] = explode(',', trim($pt_create_perm) );
1834                                         } else { // Get rid of the old restrictions
1835                                                 Title::purgeExpiredRestrictions();
1836                                         }
1837                                 } else {
1838                                         $this->mRestrictionsExpiry = Block::decodeExpiry('');
1839                                 }
1840                                 $this->mRestrictionsLoaded = true;
1841                         }
1842                 }
1843         }
1844
1845         /**
1846          * Purge expired restrictions from the page_restrictions table
1847          */
1848         static function purgeExpiredRestrictions() {
1849                 $dbw = wfGetDB( DB_MASTER );
1850                 $dbw->delete( 'page_restrictions',
1851                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
1852                         __METHOD__ );
1853
1854                 $dbw->delete( 'protected_titles',
1855                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
1856                         __METHOD__ );
1857         }
1858
1859         /**
1860          * Accessor/initialisation for mRestrictions
1861          *
1862          * @param string $action action that permission needs to be checked for
1863          * @return array the array of groups allowed to edit this article
1864          */
1865         public function getRestrictions( $action ) {
1866                 if( !$this->mRestrictionsLoaded ) {
1867                         $this->loadRestrictions();
1868                 }
1869                 return isset( $this->mRestrictions[$action] )
1870                                 ? $this->mRestrictions[$action]
1871                                 : array();
1872         }
1873
1874         /**
1875          * Is there a version of this page in the deletion archive?
1876          * @return int the number of archived revisions
1877          */
1878         public function isDeleted() {
1879                 $fname = 'Title::isDeleted';
1880                 if ( $this->getNamespace() < 0 ) {
1881                         $n = 0;
1882                 } else {
1883                         $dbr = wfGetDB( DB_SLAVE );
1884                         $n = $dbr->selectField( 'archive', 'COUNT(*)', array( 'ar_namespace' => $this->getNamespace(),
1885                                 'ar_title' => $this->getDBkey() ), $fname );
1886                         if( $this->getNamespace() == NS_IMAGE ) {
1887                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
1888                                         array( 'fa_name' => $this->getDBkey() ), $fname );
1889                         }
1890                 }
1891                 return (int)$n;
1892         }
1893
1894         /**
1895          * Get the article ID for this Title from the link cache,
1896          * adding it if necessary
1897          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select
1898          *      for update
1899          * @return int the ID
1900          */
1901         public function getArticleID( $flags = 0 ) {
1902                 $linkCache = LinkCache::singleton();
1903                 if ( $flags & GAID_FOR_UPDATE ) {
1904                         $oldUpdate = $linkCache->forUpdate( true );
1905                         $this->mArticleID = $linkCache->addLinkObj( $this );
1906                         $linkCache->forUpdate( $oldUpdate );
1907                 } else {
1908                         if ( -1 == $this->mArticleID ) {
1909                                 $this->mArticleID = $linkCache->addLinkObj( $this );
1910                         }
1911                 }
1912                 return $this->mArticleID;
1913         }
1914
1915         /**
1916          * Is this an article that is a redirect page?
1917          * Uses link cache, adding it if necessary
1918          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select for update
1919          * @return bool
1920          */
1921         public function isRedirect( $flags = 0 ) {
1922                 if( !is_null($this->mRedirect) )
1923                         return $this->mRedirect;
1924                 # Zero for special pages.
1925                 # Also, calling getArticleID() loads the field from cache!
1926                 if( !$this->getArticleID($flags) || $this->getNamespace() == NS_SPECIAL ) {
1927                         return false;
1928                 }
1929                 $linkCache = LinkCache::singleton();
1930                 $this->mRedirect = (bool)$linkCache->getGoodLinkFieldObj( $this, 'redirect' );
1931
1932                 return $this->mRedirect;
1933         }
1934
1935         /**
1936          * What is the length of this page?
1937          * Uses link cache, adding it if necessary
1938          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select for update
1939          * @return bool
1940          */
1941         public function getLength( $flags = 0 ) {
1942                 if( $this->mLength != -1 )
1943                         return $this->mLength;
1944                 # Zero for special pages.
1945                 # Also, calling getArticleID() loads the field from cache!
1946                 if( !$this->getArticleID($flags) || $this->getNamespace() == NS_SPECIAL ) {
1947                         return 0;
1948                 }
1949                 $linkCache = LinkCache::singleton();
1950                 $this->mLength = intval( $linkCache->getGoodLinkFieldObj( $this, 'length' ) );
1951
1952                 return $this->mLength;
1953         }
1954
1955         /**
1956          * What is the page_latest field for this page?
1957          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select for update
1958          * @return int
1959          */
1960         public function getLatestRevID( $flags = 0 ) {
1961                 if ($this->mLatestID !== false)
1962                         return $this->mLatestID;
1963
1964                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB(DB_MASTER) : wfGetDB(DB_SLAVE);
1965                 return $this->mLatestID = $db->selectField( 'revision',
1966                         "max(rev_id)",
1967                         array('rev_page' => $this->getArticleID($flags)),
1968                         'Title::getLatestRevID' );
1969         }
1970
1971         /**
1972          * This clears some fields in this object, and clears any associated
1973          * keys in the "bad links" section of the link cache.
1974          *
1975          * - This is called from Article::insertNewArticle() to allow
1976          * loading of the new page_id. It's also called from
1977          * Article::doDeleteArticle()
1978          *
1979          * @param int $newid the new Article ID
1980          */
1981         public function resetArticleID( $newid ) {
1982                 $linkCache = LinkCache::singleton();
1983                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
1984
1985                 if ( 0 == $newid ) { $this->mArticleID = -1; }
1986                 else { $this->mArticleID = $newid; }
1987                 $this->mRestrictionsLoaded = false;
1988                 $this->mRestrictions = array();
1989         }
1990
1991         /**
1992          * Updates page_touched for this page; called from LinksUpdate.php
1993          * @return bool true if the update succeded
1994          */
1995         public function invalidateCache() {
1996                 global $wgUseFileCache;
1997
1998                 if ( wfReadOnly() ) {
1999                         return;
2000                 }
2001
2002                 $dbw = wfGetDB( DB_MASTER );
2003                 $success = $dbw->update( 'page',
2004                         array( /* SET */
2005                                 'page_touched' => $dbw->timestamp()
2006                         ), array( /* WHERE */
2007                                 'page_namespace' => $this->getNamespace() ,
2008                                 'page_title' => $this->getDBkey()
2009                         ), 'Title::invalidateCache'
2010                 );
2011
2012                 if ($wgUseFileCache) {
2013                         $cache = new HTMLFileCache($this);
2014                         @unlink($cache->fileCacheName());
2015                 }
2016
2017                 return $success;
2018         }
2019
2020         /**
2021          * Prefix some arbitrary text with the namespace or interwiki prefix
2022          * of this object
2023          *
2024          * @param string $name the text
2025          * @return string the prefixed text
2026          * @private
2027          */
2028         /* private */ function prefix( $name ) {
2029                 $p = '';
2030                 if ( '' != $this->mInterwiki ) {
2031                         $p = $this->mInterwiki . ':';
2032                 }
2033                 if ( 0 != $this->mNamespace ) {
2034                         $p .= $this->getNsText() . ':';
2035                 }
2036                 return $p . $name;
2037         }
2038
2039         /**
2040          * Secure and split - main initialisation function for this object
2041          *
2042          * Assumes that mDbkeyform has been set, and is urldecoded
2043          * and uses underscores, but not otherwise munged.  This function
2044          * removes illegal characters, splits off the interwiki and
2045          * namespace prefixes, sets the other forms, and canonicalizes
2046          * everything.
2047          * @return bool true on success
2048          */
2049         private function secureAndSplit() {
2050                 global $wgContLang, $wgLocalInterwiki, $wgCapitalLinks;
2051
2052                 # Initialisation
2053                 static $rxTc = false;
2054                 if( !$rxTc ) {
2055                         # Matching titles will be held as illegal.
2056                         $rxTc = '/' .
2057                                 # Any character not allowed is forbidden...
2058                                 '[^' . Title::legalChars() . ']' .
2059                                 # URL percent encoding sequences interfere with the ability
2060                                 # to round-trip titles -- you can't link to them consistently.
2061                                 '|%[0-9A-Fa-f]{2}' .
2062                                 # XML/HTML character references produce similar issues.
2063                                 '|&[A-Za-z0-9\x80-\xff]+;' .
2064                                 '|&#[0-9]+;' .
2065                                 '|&#x[0-9A-Fa-f]+;' .
2066                                 '/S';
2067                 }
2068
2069                 $this->mInterwiki = $this->mFragment = '';
2070                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2071
2072                 $dbkey = $this->mDbkeyform;
2073
2074                 # Strip Unicode bidi override characters.
2075                 # Sometimes they slip into cut-n-pasted page titles, where the
2076                 # override chars get included in list displays.
2077                 $dbkey = str_replace( "\xE2\x80\x8E", '', $dbkey ); // 200E LEFT-TO-RIGHT MARK
2078                 $dbkey = str_replace( "\xE2\x80\x8F", '', $dbkey ); // 200F RIGHT-TO-LEFT MARK
2079
2080                 # Clean up whitespace
2081                 #
2082                 $dbkey = preg_replace( '/[ _]+/', '_', $dbkey );
2083                 $dbkey = trim( $dbkey, '_' );
2084
2085                 if ( '' == $dbkey ) {
2086                         return false;
2087                 }
2088
2089                 if( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2090                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2091                         return false;
2092                 }
2093
2094                 $this->mDbkeyform = $dbkey;
2095
2096                 # Initial colon indicates main namespace rather than specified default
2097                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
2098                 if ( ':' == $dbkey{0} ) {
2099                         $this->mNamespace = NS_MAIN;
2100                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
2101                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
2102                 }
2103
2104                 # Namespace or interwiki prefix
2105                 $firstPass = true;
2106                 do {
2107                         $m = array();
2108                         if ( preg_match( "/^(.+?)_*:_*(.*)$/S", $dbkey, $m ) ) {
2109                                 $p = $m[1];
2110                                 if ( $ns = $wgContLang->getNsIndex( $p )) {
2111                                         # Ordinary namespace
2112                                         $dbkey = $m[2];
2113                                         $this->mNamespace = $ns;
2114                                 } elseif( $this->getInterwikiLink( $p ) ) {
2115                                         if( !$firstPass ) {
2116                                                 # Can't make a local interwiki link to an interwiki link.
2117                                                 # That's just crazy!
2118                                                 return false;
2119                                         }
2120
2121                                         # Interwiki link
2122                                         $dbkey = $m[2];
2123                                         $this->mInterwiki = $wgContLang->lc( $p );
2124
2125                                         # Redundant interwiki prefix to the local wiki
2126                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
2127                                                 if( $dbkey == '' ) {
2128                                                         # Can't have an empty self-link
2129                                                         return false;
2130                                                 }
2131                                                 $this->mInterwiki = '';
2132                                                 $firstPass = false;
2133                                                 # Do another namespace split...
2134                                                 continue;
2135                                         }
2136
2137                                         # If there's an initial colon after the interwiki, that also
2138                                         # resets the default namespace
2139                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
2140                                                 $this->mNamespace = NS_MAIN;
2141                                                 $dbkey = substr( $dbkey, 1 );
2142                                         }
2143                                 }
2144                                 # If there's no recognized interwiki or namespace,
2145                                 # then let the colon expression be part of the title.
2146                         }
2147                         break;
2148                 } while( true );
2149
2150                 # We already know that some pages won't be in the database!
2151                 #
2152                 if ( '' != $this->mInterwiki || NS_SPECIAL == $this->mNamespace ) {
2153                         $this->mArticleID = 0;
2154                 }
2155                 $fragment = strstr( $dbkey, '#' );
2156                 if ( false !== $fragment ) {
2157                         $this->setFragment( $fragment );
2158                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
2159                         # remove whitespace again: prevents "Foo_bar_#"
2160                         # becoming "Foo_bar_"
2161                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
2162                 }
2163
2164                 # Reject illegal characters.
2165                 #
2166                 if( preg_match( $rxTc, $dbkey ) ) {
2167                         return false;
2168                 }
2169
2170                 /**
2171                  * Pages with "/./" or "/../" appearing in the URLs will often be un-
2172                  * reachable due to the way web browsers deal with 'relative' URLs.
2173                  * Also, they conflict with subpage syntax.  Forbid them explicitly.
2174                  */
2175                 if ( strpos( $dbkey, '.' ) !== false &&
2176                      ( $dbkey === '.' || $dbkey === '..' ||
2177                        strpos( $dbkey, './' ) === 0  ||
2178                        strpos( $dbkey, '../' ) === 0 ||
2179                        strpos( $dbkey, '/./' ) !== false ||
2180                        strpos( $dbkey, '/../' ) !== false  ||
2181                        substr( $dbkey, -2 ) == '/.' ||
2182                        substr( $dbkey, -3 ) == '/..' ) )
2183                 {
2184                         return false;
2185                 }
2186
2187                 /**
2188                  * Magic tilde sequences? Nu-uh!
2189                  */
2190                 if( strpos( $dbkey, '~~~' ) !== false ) {
2191                         return false;
2192                 }
2193
2194                 /**
2195                  * Limit the size of titles to 255 bytes.
2196                  * This is typically the size of the underlying database field.
2197                  * We make an exception for special pages, which don't need to be stored
2198                  * in the database, and may edge over 255 bytes due to subpage syntax
2199                  * for long titles, e.g. [[Special:Block/Long name]]
2200                  */
2201                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
2202                   strlen( $dbkey ) > 512 )
2203                 {
2204                         return false;
2205                 }
2206
2207                 /**
2208                  * Normally, all wiki links are forced to have
2209                  * an initial capital letter so [[foo]] and [[Foo]]
2210                  * point to the same place.
2211                  *
2212                  * Don't force it for interwikis, since the other
2213                  * site might be case-sensitive.
2214                  */
2215                 $this->mUserCaseDBKey = $dbkey;
2216                 if( $wgCapitalLinks && $this->mInterwiki == '') {
2217                         $dbkey = $wgContLang->ucfirst( $dbkey );
2218                 }
2219
2220                 /**
2221                  * Can't make a link to a namespace alone...
2222                  * "empty" local links can only be self-links
2223                  * with a fragment identifier.
2224                  */
2225                 if( $dbkey == '' &&
2226                         $this->mInterwiki == '' &&
2227                         $this->mNamespace != NS_MAIN ) {
2228                         return false;
2229                 }
2230                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
2231                 // IP names are not allowed for accounts, and can only be referring to
2232                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
2233                 // there are numerous ways to present the same IP. Having sp:contribs scan
2234                 // them all is silly and having some show the edits and others not is
2235                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
2236                 $dbkey = ($this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK) ?
2237                         IP::sanitizeIP( $dbkey ) : $dbkey;
2238                 // Any remaining initial :s are illegal.
2239                 if ( $dbkey !== '' && ':' == $dbkey{0} ) {
2240                         return false;
2241                 }
2242
2243                 # Fill fields
2244                 $this->mDbkeyform = $dbkey;
2245                 $this->mUrlform = wfUrlencode( $dbkey );
2246
2247                 $this->mTextform = str_replace( '_', ' ', $dbkey );
2248
2249                 return true;
2250         }
2251
2252         /**
2253          * Set the fragment for this title
2254          * This is kind of bad, since except for this rarely-used function, Title objects
2255          * are immutable. The reason this is here is because it's better than setting the
2256          * members directly, which is what Linker::formatComment was doing previously.
2257          *
2258          * @param string $fragment text
2259          * @todo clarify whether access is supposed to be public (was marked as "kind of public")
2260          */
2261         public function setFragment( $fragment ) {
2262                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
2263         }
2264
2265         /**
2266          * Get a Title object associated with the talk page of this article
2267          * @return Title the object for the talk page
2268          */
2269         public function getTalkPage() {
2270                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
2271         }
2272
2273         /**
2274          * Get a title object associated with the subject page of this
2275          * talk page
2276          *
2277          * @return Title the object for the subject page
2278          */
2279         public function getSubjectPage() {
2280                 return Title::makeTitle( MWNamespace::getSubject( $this->getNamespace() ), $this->getDBkey() );
2281         }
2282
2283         /**
2284          * Get an array of Title objects linking to this Title
2285          * Also stores the IDs in the link cache.
2286          *
2287          * WARNING: do not use this function on arbitrary user-supplied titles!
2288          * On heavily-used templates it will max out the memory.
2289          *
2290          * @param string $options may be FOR UPDATE
2291          * @return array the Title objects linking here
2292          */
2293         public function getLinksTo( $options = '', $table = 'pagelinks', $prefix = 'pl' ) {
2294                 $linkCache = LinkCache::singleton();
2295
2296                 if ( $options ) {
2297                         $db = wfGetDB( DB_MASTER );
2298                 } else {
2299                         $db = wfGetDB( DB_SLAVE );
2300                 }
2301
2302                 $res = $db->select( array( 'page', $table ),
2303                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect' ),
2304                         array(
2305                                 "{$prefix}_from=page_id",
2306                                 "{$prefix}_namespace" => $this->getNamespace(),
2307                                 "{$prefix}_title"     => $this->getDBkey() ),
2308                         __METHOD__,
2309                         $options );
2310
2311                 $retVal = array();
2312                 if ( $db->numRows( $res ) ) {
2313                         foreach( $res as $row ) {
2314                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
2315                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj, $row->page_len, $row->page_is_redirect );
2316                                         $retVal[] = $titleObj;
2317                                 }
2318                         }
2319                 }
2320                 $db->freeResult( $res );
2321                 return $retVal;
2322         }
2323
2324         /**
2325          * Get an array of Title objects using this Title as a template
2326          * Also stores the IDs in the link cache.
2327          *
2328          * WARNING: do not use this function on arbitrary user-supplied titles!
2329          * On heavily-used templates it will max out the memory.
2330          *
2331          * @param string $options may be FOR UPDATE
2332          * @return array the Title objects linking here
2333          */
2334         public function getTemplateLinksTo( $options = '' ) {
2335                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
2336         }
2337
2338         /**
2339          * Get an array of Title objects referring to non-existent articles linked from this page
2340          *
2341          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
2342          * @param string $options may be FOR UPDATE
2343          * @return array the Title objects
2344          */
2345         public function getBrokenLinksFrom( $options = '' ) {
2346                 if ( $this->getArticleId() == 0 ) {
2347                         # All links from article ID 0 are false positives
2348                         return array();
2349                 }
2350
2351                 if ( $options ) {
2352                         $db = wfGetDB( DB_MASTER );
2353                 } else {
2354                         $db = wfGetDB( DB_SLAVE );
2355                 }
2356
2357                 $res = $db->safeQuery(
2358                           "SELECT pl_namespace, pl_title
2359                              FROM !
2360                         LEFT JOIN !
2361                                ON pl_namespace=page_namespace
2362                               AND pl_title=page_title
2363                             WHERE pl_from=?
2364                               AND page_namespace IS NULL
2365                                   !",
2366                         $db->tableName( 'pagelinks' ),
2367                         $db->tableName( 'page' ),
2368                         $this->getArticleId(),
2369                         $options );
2370
2371                 $retVal = array();
2372                 if ( $db->numRows( $res ) ) {
2373                         foreach( $res as $row ) {
2374                                 $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
2375                         }
2376                 }
2377                 $db->freeResult( $res );
2378                 return $retVal;
2379         }
2380
2381
2382         /**
2383          * Get a list of URLs to purge from the Squid cache when this
2384          * page changes
2385          *
2386          * @return array the URLs
2387          */
2388         public function getSquidURLs() {
2389                 global $wgContLang;
2390
2391                 $urls = array(
2392                         $this->getInternalURL(),
2393                         $this->getInternalURL( 'action=history' )
2394                 );
2395
2396                 // purge variant urls as well
2397                 if($wgContLang->hasVariants()){
2398                         $variants = $wgContLang->getVariants();
2399                         foreach($variants as $vCode){
2400                                 if($vCode==$wgContLang->getCode()) continue; // we don't want default variant
2401                                 $urls[] = $this->getInternalURL('',$vCode);
2402                         }
2403                 }
2404
2405                 return $urls;
2406         }
2407
2408         public function purgeSquid() {
2409                 global $wgUseSquid;
2410                 if ( $wgUseSquid ) {
2411                         $urls = $this->getSquidURLs();
2412                         $u = new SquidUpdate( $urls );
2413                         $u->doUpdate();
2414                 }
2415         }
2416
2417         /**
2418          * Move this page without authentication
2419          * @param Title &$nt the new page Title
2420          */
2421         public function moveNoAuth( &$nt ) {
2422                 return $this->moveTo( $nt, false );
2423         }
2424
2425         /**
2426          * Check whether a given move operation would be valid.
2427          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
2428          * @param Title &$nt the new title
2429          * @param bool $auth indicates whether $wgUser's permissions
2430          *      should be checked
2431          * @param string $reason is the log summary of the move, used for spam checking
2432          * @return mixed True on success, getUserPermissionsErrors()-like array on failure
2433          */
2434         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
2435                 $errors = array();
2436                 if( !$nt ) {
2437                         // Normally we'd add this to $errors, but we'll get
2438                         // lots of syntax errors if $nt is not an object
2439                         return array(array('badtitletext'));
2440                 }
2441                 if( $this->equals( $nt ) ) {
2442                         $errors[] = array('selfmove');
2443                 }
2444                 if( !$this->isMovable() || !$nt->isMovable() ) {
2445                         $errors[] = array('immobile_namespace');
2446                 }
2447
2448                 $oldid = $this->getArticleID();
2449                 $newid = $nt->getArticleID();
2450
2451                 if ( strlen( $nt->getDBkey() ) < 1 ) {
2452                         $errors[] = array('articleexists');
2453                 }
2454                 if ( ( '' == $this->getDBkey() ) ||
2455                          ( !$oldid ) ||
2456                      ( '' == $nt->getDBkey() ) ) {
2457                         $errors[] = array('badarticleerror');
2458                 }
2459
2460                 // Image-specific checks
2461                 if( $this->getNamespace() == NS_IMAGE ) {
2462                         $file = wfLocalFile( $this );
2463                         if( $file->exists() ) {
2464                                 if( $nt->getNamespace() != NS_IMAGE ) {
2465                                         $errors[] = array('imagenocrossnamespace');
2466                                 }
2467                                 if( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
2468                                         $errors[] = array('imageinvalidfilename');
2469                                 }
2470                                 if( !File::checkExtensionCompatibility( $file, $nt->getDbKey() ) ) {
2471                                         $errors[] = array('imagetypemismatch');
2472                                 }
2473                         }
2474                 }
2475
2476                 if ( $auth ) {
2477                         global $wgUser;
2478                         $errors = array_merge($errors,
2479                                         $this->getUserPermissionsErrors('move', $wgUser),
2480                                         $this->getUserPermissionsErrors('edit', $wgUser),
2481                                         $nt->getUserPermissionsErrors('move', $wgUser),
2482                                         $nt->getUserPermissionsErrors('edit', $wgUser));
2483                 }
2484
2485                 global $wgUser;
2486                 $err = null;
2487                 if( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
2488                         $errors[] = array('hookaborted', $err);
2489                 }
2490
2491                 # The move is allowed only if (1) the target doesn't exist, or
2492                 # (2) the target is a redirect to the source, and has no history
2493                 # (so we can undo bad moves right after they're done).
2494
2495                 if ( 0 != $newid ) { # Target exists; check for validity
2496                         if ( ! $this->isValidMoveTarget( $nt ) ) {
2497                                 $errors[] = array('articleexists');
2498                         }
2499                 } else {
2500                         $tp = $nt->getTitleProtection();
2501                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
2502                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
2503                                 $errors[] = array('cantmove-titleprotected');
2504                         }
2505                 }
2506                 if(empty($errors))
2507                         return true;
2508                 return $errors;
2509         }
2510
2511         /**
2512          * Move a title to a new location
2513          * @param Title &$nt the new title
2514          * @param bool $auth indicates whether $wgUser's permissions
2515          *      should be checked
2516          * @param string $reason The reason for the move
2517          * @param bool $createRedirect Whether to create a redirect from the old title to the new title.
2518          *  Ignored if the user doesn't have the suppressredirect right.
2519          * @return mixed true on success, getUserPermissionsErrors()-like array on failure
2520          */
2521         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
2522                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
2523                 if( is_array( $err ) ) {
2524                         return $err;
2525                 }
2526
2527                 $pageid = $this->getArticleID();
2528                 if( $nt->exists() ) {
2529                         $err = $this->moveOverExistingRedirect( $nt, $reason, $createRedirect );
2530                         $pageCountChange = ($createRedirect ? 0 : -1);
2531                 } else { # Target didn't exist, do normal move.
2532                         $err = $this->moveToNewTitle( $nt, $reason, $createRedirect );
2533                         $pageCountChange = ($createRedirect ? 1 : 0);
2534                 }
2535
2536                 if( is_array( $err ) ) {
2537                         return $err;
2538                 }
2539                 $redirid = $this->getArticleID();
2540
2541                 // Category memberships include a sort key which may be customized.
2542                 // If it's left as the default (the page title), we need to update
2543                 // the sort key to match the new title.
2544                 //
2545                 // Be careful to avoid resetting cl_timestamp, which may disturb
2546                 // time-based lists on some sites.
2547                 //
2548                 // Warning -- if the sort key is *explicitly* set to the old title,
2549                 // we can't actually distinguish it from a default here, and it'll
2550                 // be set to the new title even though it really shouldn't.
2551                 // It'll get corrected on the next edit, but resetting cl_timestamp.
2552                 $dbw = wfGetDB( DB_MASTER );
2553                 $dbw->update( 'categorylinks',
2554                         array(
2555                                 'cl_sortkey' => $nt->getPrefixedText(),
2556                                 'cl_timestamp=cl_timestamp' ),
2557                         array(
2558                                 'cl_from' => $pageid,
2559                                 'cl_sortkey' => $this->getPrefixedText() ),
2560                         __METHOD__ );
2561
2562                 # Update watchlists
2563
2564                 $oldnamespace = $this->getNamespace() & ~1;
2565                 $newnamespace = $nt->getNamespace() & ~1;
2566                 $oldtitle = $this->getDBkey();
2567                 $newtitle = $nt->getDBkey();
2568
2569                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
2570                         WatchedItem::duplicateEntries( $this, $nt );
2571                 }
2572
2573                 # Update search engine
2574                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
2575                 $u->doUpdate();
2576                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
2577                 $u->doUpdate();
2578
2579                 # Update site_stats
2580                 if( $this->isContentPage() && !$nt->isContentPage() ) {
2581                         # No longer a content page
2582                         # Not viewed, edited, removing
2583                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange );
2584                 } elseif( !$this->isContentPage() && $nt->isContentPage() ) {
2585                         # Now a content page
2586                         # Not viewed, edited, adding
2587                         $u = new SiteStatsUpdate( 0, 1, +1, $pageCountChange );
2588                 } elseif( $pageCountChange ) {
2589                         # Redirect added
2590                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
2591                 } else {
2592                         # Nothing special
2593                         $u = false;
2594                 }
2595                 if( $u )
2596                         $u->doUpdate();
2597                 # Update message cache for interface messages
2598                 if( $nt->getNamespace() == NS_MEDIAWIKI ) {
2599                         global $wgMessageCache;
2600                         $oldarticle = new Article( $this );
2601                         $wgMessageCache->replace( $this->getDBkey(), $oldarticle->getContent() );
2602                         $newarticle = new Article( $nt );
2603                         $wgMessageCache->replace( $nt->getDBkey(), $newarticle->getContent() );
2604                 }
2605
2606                 global $wgUser;
2607                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
2608                 return true;
2609         }
2610
2611         /**
2612          * Move page to a title which is at present a redirect to the
2613          * source page
2614          *
2615          * @param Title &$nt the page to move to, which should currently
2616          *      be a redirect
2617          * @param string $reason The reason for the move
2618          * @param bool $createRedirect Whether to leave a redirect at the old title.
2619          *  Ignored if the user doesn't have the suppressredirect right
2620          */
2621         private function moveOverExistingRedirect( &$nt, $reason = '', $createRedirect = true ) {
2622                 global $wgUseSquid, $wgUser;
2623                 $fname = 'Title::moveOverExistingRedirect';
2624                 $comment = wfMsgForContent( '1movedto2_redir', $this->getPrefixedText(), $nt->getPrefixedText() );
2625
2626                 if ( $reason ) {
2627                         $comment .= ": $reason";
2628                 }
2629
2630                 $now = wfTimestampNow();
2631                 $newid = $nt->getArticleID();
2632                 $oldid = $this->getArticleID();
2633                 $latest = $this->getLatestRevID();
2634
2635                 $dbw = wfGetDB( DB_MASTER );
2636                 $dbw->begin();
2637
2638                 # Delete the old redirect. We don't save it to history since
2639                 # by definition if we've got here it's rather uninteresting.
2640                 # We have to remove it so that the next step doesn't trigger
2641                 # a conflict on the unique namespace+title index...
2642                 $dbw->delete( 'page', array( 'page_id' => $newid ), $fname );
2643                 if ( !$dbw->cascadingDeletes() ) {
2644                         $dbw->delete( 'revision', array( 'rev_page' => $newid ), __METHOD__ );
2645                         global $wgUseTrackbacks;
2646                         if ($wgUseTrackbacks)
2647                                 $dbw->delete( 'trackbacks', array( 'tb_page' => $newid ), __METHOD__ );
2648                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
2649                         $dbw->delete( 'imagelinks', array( 'il_from' => $newid ), __METHOD__ );
2650                         $dbw->delete( 'categorylinks', array( 'cl_from' => $newid ), __METHOD__ );
2651                         $dbw->delete( 'templatelinks', array( 'tl_from' => $newid ), __METHOD__ );
2652                         $dbw->delete( 'externallinks', array( 'el_from' => $newid ), __METHOD__ );
2653                         $dbw->delete( 'langlinks', array( 'll_from' => $newid ), __METHOD__ );
2654                         $dbw->delete( 'redirect', array( 'rd_from' => $newid ), __METHOD__ );
2655                 }
2656
2657                 # Save a null revision in the page's history notifying of the move
2658                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
2659                 $nullRevId = $nullRevision->insertOn( $dbw );
2660
2661                 $article = new Article( $this );
2662                 wfRunHooks( 'NewRevisionFromEditComplete', array($article, $nullRevision, $latest) );
2663
2664                 # Change the name of the target page:
2665                 $dbw->update( 'page',
2666                         /* SET */ array(
2667                                 'page_touched'   => $dbw->timestamp($now),
2668                                 'page_namespace' => $nt->getNamespace(),
2669                                 'page_title'     => $nt->getDBkey(),
2670                                 'page_latest'    => $nullRevId,
2671                         ),
2672                         /* WHERE */ array( 'page_id' => $oldid ),
2673                         $fname
2674                 );
2675                 $nt->resetArticleID( $oldid );
2676
2677                 # Recreate the redirect, this time in the other direction.
2678                 if( $createRedirect || !$wgUser->isAllowed('suppressredirect') ) {
2679                         $mwRedir = MagicWord::get( 'redirect' );
2680                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
2681                         $redirectArticle = new Article( $this );
2682                         $newid = $redirectArticle->insertOn( $dbw );
2683                         $redirectRevision = new Revision( array(
2684                                 'page'    => $newid,
2685                                 'comment' => $comment,
2686                                 'text'    => $redirectText ) );
2687                         $redirectRevision->insertOn( $dbw );
2688                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
2689
2690                         wfRunHooks( 'NewRevisionFromEditComplete', array($redirectArticle, $redirectRevision, false) );
2691
2692                         # Now, we record the link from the redirect to the new title.
2693                         # It should have no other outgoing links...
2694                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), $fname );
2695                         $dbw->insert( 'pagelinks',
2696                                 array(
2697                                         'pl_from'      => $newid,
2698                                         'pl_namespace' => $nt->getNamespace(),
2699                                         'pl_title'     => $nt->getDBkey() ),
2700                                 $fname );
2701                 } else {
2702                         $this->resetArticleID( 0 );
2703                 }
2704
2705                 # Move an image if this is a file
2706                 if( $this->getNamespace() == NS_IMAGE ) {
2707                         $file = wfLocalFile( $this );
2708                         if( $file->exists() ) {
2709                                 $status = $file->move( $nt );
2710                                 if( !$status->isOk() ) {
2711                                         $dbw->rollback();
2712                                         return $status->getErrorsArray();
2713                                 }
2714                         }
2715                 }
2716                 $dbw->commit();
2717
2718                 # Log the move
2719                 $log = new LogPage( 'move' );
2720                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText() ) );
2721
2722                 # Purge squid
2723                 if ( $wgUseSquid ) {
2724                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
2725                         $u = new SquidUpdate( $urls );
2726                         $u->doUpdate();
2727                 }
2728
2729         }
2730
2731         /**
2732          * Move page to non-existing title.
2733          * @param Title &$nt the new Title
2734          * @param string $reason The reason for the move
2735          * @param bool $createRedirect Whether to create a redirect from the old title to the new title
2736          *  Ignored if the user doesn't have the suppressredirect right
2737          */
2738         private function moveToNewTitle( &$nt, $reason = '', $createRedirect = true ) {
2739                 global $wgUseSquid, $wgUser;
2740                 $fname = 'MovePageForm::moveToNewTitle';
2741                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
2742                 if ( $reason ) {
2743                         $comment .= ": $reason";
2744                 }
2745
2746                 $newid = $nt->getArticleID();
2747                 $oldid = $this->getArticleID();
2748                 $latest = $this->getLatestRevId();
2749
2750                 $dbw = wfGetDB( DB_MASTER );
2751                 $dbw->begin();
2752                 $now = $dbw->timestamp();
2753
2754                 # Save a null revision in the page's history notifying of the move
2755                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
2756                 $nullRevId = $nullRevision->insertOn( $dbw );
2757
2758                 $article = new Article( $this );
2759                 wfRunHooks( 'NewRevisionFromEditComplete', array($article, $nullRevision, $latest) );
2760
2761                 # Rename page entry
2762                 $dbw->update( 'page',
2763                         /* SET */ array(
2764                                 'page_touched'   => $now,
2765                                 'page_namespace' => $nt->getNamespace(),
2766                                 'page_title'     => $nt->getDBkey(),
2767                                 'page_latest'    => $nullRevId,
2768                         ),
2769                         /* WHERE */ array( 'page_id' => $oldid ),
2770                         $fname
2771                 );
2772                 $nt->resetArticleID( $oldid );
2773
2774                 if( $createRedirect || !$wgUser->isAllowed('suppressredirect') ) {
2775                         # Insert redirect
2776                         $mwRedir = MagicWord::get( 'redirect' );
2777                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
2778                         $redirectArticle = new Article( $this );
2779                         $newid = $redirectArticle->insertOn( $dbw );
2780                         $redirectRevision = new Revision( array(
2781                                 'page'    => $newid,
2782                                 'comment' => $comment,
2783                                 'text'    => $redirectText ) );
2784                         $redirectRevision->insertOn( $dbw );
2785                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
2786
2787                         wfRunHooks( 'NewRevisionFromEditComplete', array($redirectArticle, $redirectRevision, false) );
2788
2789                         # Record the just-created redirect's linking to the page
2790                         $dbw->insert( 'pagelinks',
2791                                 array(
2792                                         'pl_from'      => $newid,
2793                                         'pl_namespace' => $nt->getNamespace(),
2794                                         'pl_title'     => $nt->getDBkey() ),
2795                                 $fname );
2796                 } else {
2797                         $this->resetArticleID( 0 );
2798                 }
2799
2800                 # Move an image if this is a file
2801                 if( $this->getNamespace() == NS_IMAGE ) {
2802                         $file = wfLocalFile( $this );
2803                         if( $file->exists() ) {
2804                                 $status = $file->move( $nt );
2805                                 if( !$status->isOk() ) {
2806                                         $dbw->rollback();
2807                                         return $status->getErrorsArray();
2808                                 }
2809                         }
2810                 }
2811                 $dbw->commit();
2812
2813                 # Log the move
2814                 $log = new LogPage( 'move' );
2815                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText()) );
2816
2817                 # Purge caches as per article creation
2818                 Article::onArticleCreate( $nt );
2819
2820                 # Purge old title from squid
2821                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
2822                 $this->purgeSquid();
2823
2824         }
2825
2826         /**
2827          * Checks if $this can be moved to a given Title
2828          * - Selects for update, so don't call it unless you mean business
2829          *
2830          * @param Title &$nt the new title to check
2831          */
2832         public function isValidMoveTarget( $nt ) {
2833
2834                 $fname = 'Title::isValidMoveTarget';
2835                 $dbw = wfGetDB( DB_MASTER );
2836
2837                 # Is it an existsing file?
2838                 if( $nt->getNamespace() == NS_IMAGE ) {
2839                         $file = wfLocalFile( $nt );
2840                         if( $file->exists() ) {
2841                                 wfDebug( __METHOD__ . ": file exists\n" );
2842                                 return false;
2843                         }
2844                 }
2845
2846                 # Is it a redirect?
2847                 $id  = $nt->getArticleID();
2848                 $obj = $dbw->selectRow( array( 'page', 'revision', 'text'),
2849                         array( 'page_is_redirect','old_text','old_flags' ),
2850                         array( 'page_id' => $id, 'page_latest=rev_id', 'rev_text_id=old_id' ),
2851                         $fname, 'FOR UPDATE' );
2852
2853                 if ( !$obj || 0 == $obj->page_is_redirect ) {
2854                         # Not a redirect
2855                         wfDebug( __METHOD__ . ": not a redirect\n" );
2856                         return false;
2857                 }
2858                 $text = Revision::getRevisionText( $obj );
2859
2860                 # Does the redirect point to the source?
2861                 # Or is it a broken self-redirect, usually caused by namespace collisions?
2862                 $m = array();
2863                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
2864                         $redirTitle = Title::newFromText( $m[1] );
2865                         if( !is_object( $redirTitle ) ||
2866                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
2867                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
2868                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
2869                                 return false;
2870                         }
2871                 } else {
2872                         # Fail safe
2873                         wfDebug( __METHOD__ . ": failsafe\n" );
2874                         return false;
2875                 }
2876
2877                 # Does the article have a history?
2878                 $row = $dbw->selectRow( array( 'page', 'revision'),
2879                         array( 'rev_id' ),
2880                         array( 'page_namespace' => $nt->getNamespace(),
2881                                 'page_title' => $nt->getDBkey(),
2882                                 'page_id=rev_page AND page_latest != rev_id'
2883                         ), $fname, 'FOR UPDATE'
2884                 );
2885
2886                 # Return true if there was no history
2887                 return $row === false;
2888         }
2889
2890         /**
2891          * Can this title be added to a user's watchlist?
2892          *
2893          * @return bool
2894          */
2895         public function isWatchable() {
2896                 return !$this->isExternal()
2897                         && MWNamespace::isWatchable( $this->getNamespace() );
2898         }
2899
2900         /**
2901          * Get categories to which this Title belongs and return an array of
2902          * categories' names.
2903          *
2904          * @return array an array of parents in the form:
2905          *      $parent => $currentarticle
2906          */
2907         public function getParentCategories() {
2908                 global $wgContLang;
2909
2910                 $titlekey = $this->getArticleId();
2911                 $dbr = wfGetDB( DB_SLAVE );
2912                 $categorylinks = $dbr->tableName( 'categorylinks' );
2913
2914                 # NEW SQL
2915                 $sql = "SELECT * FROM $categorylinks"
2916                      ." WHERE cl_from='$titlekey'"
2917                          ." AND cl_from <> '0'"
2918                          ." ORDER BY cl_sortkey";
2919
2920                 $res = $dbr->query( $sql );
2921
2922                 if( $dbr->numRows( $res ) > 0 ) {
2923                         foreach( $res as $row )
2924                                 //$data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
2925                                 $data[$wgContLang->getNSText( NS_CATEGORY ).':'.$row->cl_to] = $this->getFullText();
2926                         $dbr->freeResult( $res );
2927                 } else {
2928                         $data = array();
2929                 }
2930                 return $data;
2931         }
2932
2933         /**
2934          * Get a tree of parent categories
2935          * @param array $children an array with the children in the keys, to check for circular refs
2936          * @return array
2937          */
2938         public function getParentCategoryTree( $children = array() ) {
2939                 $stack = array();
2940                 $parents = $this->getParentCategories();
2941
2942                 if( $parents ) {
2943                         foreach( $parents as $parent => $current ) {
2944                                 if ( array_key_exists( $parent, $children ) ) {
2945                                         # Circular reference
2946                                         $stack[$parent] = array();
2947                                 } else {
2948                                         $nt = Title::newFromText($parent);
2949                                         if ( $nt ) {
2950                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array($parent => 1) );
2951                                         }
2952                                 }
2953                         }
2954                         return $stack;
2955                 } else {
2956                         return array();
2957                 }
2958         }
2959
2960
2961         /**
2962          * Get an associative array for selecting this title from
2963          * the "page" table
2964          *
2965          * @return array
2966          */
2967         public function pageCond() {
2968                 return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
2969         }
2970
2971         /**
2972          * Get the revision ID of the previous revision
2973          *
2974          * @param integer $revId Revision ID. Get the revision that was before this one.
2975          * @param integer $flags, GAID_FOR_UPDATE
2976          * @return integer $oldrevision|false
2977          */
2978         public function getPreviousRevisionID( $revId, $flags=0 ) {
2979                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
2980                 return $db->selectField( 'revision', 'rev_id',
2981                         array(
2982                                 'rev_page' => $this->getArticleId($flags),
2983                                 'rev_id < ' . intval( $revId )
2984                         ),
2985                         __METHOD__,
2986                         array( 'ORDER BY' => 'rev_id DESC' )
2987                 );
2988         }
2989
2990         /**
2991          * Get the revision ID of the next revision
2992          *
2993          * @param integer $revId Revision ID. Get the revision that was after this one.
2994          * @param integer $flags, GAID_FOR_UPDATE
2995          * @return integer $oldrevision|false
2996          */
2997         public function getNextRevisionID( $revId, $flags=0 ) {
2998                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
2999                 return $db->selectField( 'revision', 'rev_id',
3000                         array(
3001                                 'rev_page' => $this->getArticleId($flags),
3002                                 'rev_id > ' . intval( $revId )
3003                         ),
3004                         __METHOD__,
3005                         array( 'ORDER BY' => 'rev_id' )
3006                 );
3007         }
3008
3009         /**
3010          * Get the number of revisions between the given revision IDs.
3011          * Used for diffs and other things that really need it.
3012          *
3013          * @param integer $old  Revision ID.
3014          * @param integer $new  Revision ID.
3015          * @return integer  Number of revisions between these IDs.
3016          */
3017         public function countRevisionsBetween( $old, $new ) {
3018                 $dbr = wfGetDB( DB_SLAVE );
3019                 return $dbr->selectField( 'revision', 'count(*)',
3020                         'rev_page = ' . intval( $this->getArticleId() ) .
3021                         ' AND rev_id > ' . intval( $old ) .
3022                         ' AND rev_id < ' . intval( $new ),
3023                         __METHOD__,
3024                         array( 'USE INDEX' => 'PRIMARY' ) );
3025         }
3026
3027         /**
3028          * Compare with another title.
3029          *
3030          * @param Title $title
3031          * @return bool
3032          */
3033         public function equals( Title $title ) {
3034                 // Note: === is necessary for proper matching of number-like titles.
3035                 return $this->getInterwiki() === $title->getInterwiki()
3036                         && $this->getNamespace() == $title->getNamespace()
3037                         && $this->getDBkey() === $title->getDBkey();
3038         }
3039
3040         /**
3041          * Callback for usort() to do title sorts by (namespace, title)
3042          */
3043         static function compare( $a, $b ) {
3044                 if( $a->getNamespace() == $b->getNamespace() ) {
3045                         return strcmp( $a->getText(), $b->getText() );
3046                 } else {
3047                         return $a->getNamespace() - $b->getNamespace();
3048                 }
3049         }
3050
3051         /**
3052          * Return a string representation of this title
3053          *
3054          * @return string
3055          */
3056         public function __toString() {
3057                 return $this->getPrefixedText();
3058         }
3059
3060         /**
3061          * Check if page exists
3062          * @return bool
3063          */
3064         public function exists() {
3065                 return $this->getArticleId() != 0;
3066         }
3067
3068         /**
3069          * Do we know that this title definitely exists, or should we otherwise
3070          * consider that it exists?
3071          *
3072          * @return bool
3073          */
3074         public function isAlwaysKnown() {
3075                 // If the page is form Mediawiki:message/lang, calling wfMsgWeirdKey causes
3076                 // the full l10n of that language to be loaded. That takes much memory and
3077                 // isn't needed. So we strip the language part away.
3078                 // Also, extension messages which are not loaded, are shown as red, because
3079                 // we don't call MessageCache::loadAllMessages.
3080                 list( $basename, /* rest */ ) = explode( '/', $this->mDbkeyform, 2 );
3081                 return $this->isExternal()
3082                         || ( $this->mNamespace == NS_MAIN && $this->mDbkeyform == '' )
3083                         || ( $this->mNamespace == NS_MEDIAWIKI && wfMsgWeirdKey( $basename ) );
3084         }
3085
3086         /**
3087          * Update page_touched timestamps and send squid purge messages for
3088          * pages linking to this title. May be sent to the job queue depending
3089          * on the number of links. Typically called on create and delete.
3090          */
3091         public function touchLinks() {
3092                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
3093                 $u->doUpdate();
3094
3095                 if ( $this->getNamespace() == NS_CATEGORY ) {
3096                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
3097                         $u->doUpdate();
3098                 }
3099         }
3100
3101         /**
3102          * Get the last touched timestamp
3103          */
3104         public function getTouched() {
3105                 $dbr = wfGetDB( DB_SLAVE );
3106                 $touched = $dbr->selectField( 'page', 'page_touched',
3107                         array(
3108                                 'page_namespace' => $this->getNamespace(),
3109                                 'page_title' => $this->getDBkey()
3110                         ), __METHOD__
3111                 );
3112                 return $touched;
3113         }
3114
3115         public function trackbackURL() {
3116                 global $wgTitle, $wgScriptPath, $wgServer;
3117
3118                 return "$wgServer$wgScriptPath/trackback.php?article="
3119                         . htmlspecialchars(urlencode($wgTitle->getPrefixedDBkey()));
3120         }
3121
3122         public function trackbackRDF() {
3123                 $url = htmlspecialchars($this->getFullURL());
3124                 $title = htmlspecialchars($this->getText());
3125                 $tburl = $this->trackbackURL();
3126
3127                 // Autodiscovery RDF is placed in comments so HTML validator
3128                 // won't barf. This is a rather icky workaround, but seems
3129                 // frequently used by this kind of RDF thingy.
3130                 //
3131                 // Spec: http://www.sixapart.com/pronet/docs/trackback_spec
3132                 return "<!--
3133 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
3134          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
3135          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
3136 <rdf:Description
3137    rdf:about=\"$url\"
3138    dc:identifier=\"$url\"
3139    dc:title=\"$title\"
3140    trackback:ping=\"$tburl\" />
3141 </rdf:RDF>
3142 -->";
3143         }
3144
3145         /**
3146          * Generate strings used for xml 'id' names in monobook tabs
3147          * @return string
3148          */
3149         public function getNamespaceKey() {
3150                 global $wgContLang;
3151                 switch ($this->getNamespace()) {
3152                         case NS_MAIN:
3153                         case NS_TALK:
3154                                 return 'nstab-main';
3155                         case NS_USER:
3156                         case NS_USER_TALK:
3157                                 return 'nstab-user';
3158                         case NS_MEDIA:
3159                                 return 'nstab-media';
3160                         case NS_SPECIAL:
3161                                 return 'nstab-special';
3162                         case NS_PROJECT:
3163                         case NS_PROJECT_TALK:
3164                                 return 'nstab-project';
3165                         case NS_IMAGE:
3166                         case NS_IMAGE_TALK:
3167                                 return 'nstab-image';
3168                         case NS_MEDIAWIKI:
3169                         case NS_MEDIAWIKI_TALK:
3170                                 return 'nstab-mediawiki';
3171                         case NS_TEMPLATE:
3172                         case NS_TEMPLATE_TALK:
3173                                 return 'nstab-template';
3174                         case NS_HELP:
3175                         case NS_HELP_TALK:
3176                                 return 'nstab-help';
3177                         case NS_CATEGORY:
3178                         case NS_CATEGORY_TALK:
3179                                 return 'nstab-category';
3180                         default:
3181                                 return 'nstab-' . $wgContLang->lc( $this->getSubjectNsText() );
3182                 }
3183         }
3184
3185         /**
3186          * Returns true if this title resolves to the named special page
3187          * @param string $name The special page name
3188          */
3189         public function isSpecial( $name ) {
3190                 if ( $this->getNamespace() == NS_SPECIAL ) {
3191                         list( $thisName, /* $subpage */ ) = SpecialPage::resolveAliasWithSubpage( $this->getDBkey() );
3192                         if ( $name == $thisName ) {
3193                                 return true;
3194                         }
3195                 }
3196                 return false;
3197         }
3198
3199         /**
3200          * If the Title refers to a special page alias which is not the local default,
3201          * returns a new Title which points to the local default. Otherwise, returns $this.
3202          */
3203         public function fixSpecialName() {
3204                 if ( $this->getNamespace() == NS_SPECIAL ) {
3205                         $canonicalName = SpecialPage::resolveAlias( $this->mDbkeyform );
3206                         if ( $canonicalName ) {
3207                                 $localName = SpecialPage::getLocalNameFor( $canonicalName );
3208                                 if ( $localName != $this->mDbkeyform ) {
3209                                         return Title::makeTitle( NS_SPECIAL, $localName );
3210                                 }
3211                         }
3212                 }
3213                 return $this;
3214         }
3215
3216         /**
3217          * Is this Title in a namespace which contains content?
3218          * In other words, is this a content page, for the purposes of calculating
3219          * statistics, etc?
3220          *
3221          * @return bool
3222          */
3223         public function isContentPage() {
3224                 return MWNamespace::isContent( $this->getNamespace() );
3225         }
3226
3227         public function getRedirectsHere( $ns = null ) {
3228                 $redirs = array();
3229
3230                 $dbr = wfGetDB( DB_SLAVE );
3231                 $where = array(
3232                         'rd_namespace' => $this->getNamespace(),
3233                         'rd_title' => $this->getDBkey(),
3234                         'rd_from = page_id'
3235                 );
3236                 if ( !is_null($ns) ) $where['page_namespace'] = $ns;
3237
3238                 $res = $dbr->select(
3239                         array( 'redirect', 'page' ),
3240                         array( 'page_namespace', 'page_title' ),
3241                         $where,
3242                         __METHOD__
3243                 );
3244
3245
3246                 foreach( $res as $row ) {
3247                         $redirs[] = self::newFromRow( $row );
3248                 }
3249                 return $redirs;
3250         }
3251 }