includes/Title.php

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