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                 # Check regular protection levels
 944                 if( $action == 'edit' || $action == '' ) {
 945                         $r = $this->getRestrictions( 'edit' );
 946                         foreach( $wgRestrictionLevels as $level ) {
 947                                 if( in_array( $level, $r ) && $level != '' ) {
 948                                         return( true );
 949                                 }
 950                         }
 951                 }
 952
 953                 if( $action == 'move' || $action == '' ) {
 954                         $r = $this->getRestrictions( 'move' );
 955                         foreach( $wgRestrictionLevels as $level ) {
 956                                 if( in_array( $level, $r ) && $level != '' ) {
 957                                         return( true );
 958                                 }
 959                         }
 960                 }
 961
 962                 return false;
 963         }
 964
 965         /**
 966          * Is $wgUser is watching this page?
 967          * @return boolean
 968          */
 969         public function userIsWatching() {
 970                 global $wgUser;
 971
 972                 if ( is_null( $this->mWatched ) ) {
 973                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn()) {
 974                                 $this->mWatched = false;
 975                         } else {
 976                                 $this->mWatched = $wgUser->isWatched( $this );
 977                         }
 978                 }
 979                 return $this->mWatched;
 980         }
 981
 982         /**
 983          * Can $wgUser perform $action on this page?
 984          * This skips potentially expensive cascading permission checks.
 985          *
 986          * Suitable for use for nonessential UI controls in common cases, but
 987          * _not_ for functional access control.
 988          *
 989          * May provide false positives, but should never provide a false negative.
 990          *
 991          * @param string $action action that permission needs to be checked for
 992          * @return boolean
 993          */
 994         public function quickUserCan( $action ) {
 995                 return $this->userCan( $action, false );
 996         }
 997
 998         /**
 999          * Can $wgUser perform $action on this page?
1000          * @param string $action action that permission needs to be checked for
1001          * @param bool $doExpensiveQueries Set this to false to avoid doing unnecessary queries.
1002          * @return boolean
1003          */
1004         public function userCan( $action, $doExpensiveQueries = true ) {
1005                 $fname = 'Title::userCan';
1006                 wfProfileIn( $fname );
1007
1008                 global $wgUser, $wgNamespaceProtection;
1009
1010                 $result = null;
1011                 wfRunHooks( 'userCan', array( &$this, &$wgUser, $action, &$result ) );
1012                 if ( $result !== null ) {
1013                         wfProfileOut( $fname );
1014                         return $result;
1015                 }
1016
1017                 if( NS_SPECIAL == $this->mNamespace ) {
1018                         wfProfileOut( $fname );
1019                         return false;
1020                 }
1021
1022                 if ( array_key_exists( $this->mNamespace, $wgNamespaceProtection ) ) {
1023                         $nsProt = $wgNamespaceProtection[ $this->mNamespace ];
1024                         if ( !is_array($nsProt) ) $nsProt = array($nsProt);
1025                         foreach( $nsProt as $right ) {
1026                                 if( '' != $right && !$wgUser->isAllowed( $right ) ) {
1027                                         wfProfileOut( $fname );
1028                                         return false;
1029                                 }
1030                         }
1031                 }
1032
1033                 if( $this->mDbkeyform == '_' ) {
1034                         # FIXME: Is this necessary? Shouldn't be allowed anyway...
1035                         wfProfileOut( $fname );
1036                         return false;
1037                 }
1038
1039                 # protect css/js subpages of user pages
1040                 # XXX: this might be better using restrictions
1041                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssJsSubpage() from working
1042                 if( $this->isCssJsSubpage()
1043                         && !$wgUser->isAllowed('editinterface')
1044                         && !preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) ) {
1045                         wfProfileOut( $fname );
1046                         return false;
1047                 }
1048
1049                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1050                         # We /could/ use the protection level on the source page, but it's fairly ugly
1051                         #  as we have to establish a precedence hierarchy for pages included by multiple
1052                         #  cascade-protected pages. So just restrict it to people with 'protect' permission,
1053                         #  as they could remove the protection anyway.
1054                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1055                         # Cascading protection depends on more than this page...
1056                         # Several cascading protected pages may include this page...
1057                         # Check each cascading level
1058                         # This is only for protection restrictions, not for all actions
1059                         if( $cascadingSources > 0 && isset($restrictions[$action]) ) {
1060                                 foreach( $restrictions[$action] as $right ) {
1061                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1062                                         if( '' != $right && !$wgUser->isAllowed( $right ) ) {
1063                                                 wfProfileOut( $fname );
1064                                                 return false;
1065                                         }
1066                                 }
1067                         }
1068                 }
1069
1070                 foreach( $this->getRestrictions($action) as $right ) {
1071                         // Backwards compatibility, rewrite sysop -> protect
1072                         if ( $right == 'sysop' ) {
1073                                 $right = 'protect';
1074                         }
1075                         if( '' != $right && !$wgUser->isAllowed( $right ) ) {
1076                                 wfProfileOut( $fname );
1077                                 return false;
1078                         }
1079                 }
1080
1081                 if( $action == 'move' &&
1082                         !( $this->isMovable() && $wgUser->isAllowed( 'move' ) ) ) {
1083                         wfProfileOut( $fname );
1084                         return false;
1085                 }
1086
1087                 if( $action == 'create' ) {
1088                         if( (  $this->isTalkPage() && !$wgUser->isAllowed( 'createtalk' ) ) ||
1089                                 ( !$this->isTalkPage() && !$wgUser->isAllowed( 'createpage' ) ) ) {
1090                                 wfProfileOut( $fname );
1091                                 return false;
1092                         }
1093                 }
1094
1095                 wfProfileOut( $fname );
1096                 return true;
1097         }
1098
1099         /**
1100          * Can $wgUser edit this page?
1101          * @return boolean
1102          * @deprecated use userCan('edit')
1103          */
1104         public function userCanEdit( $doExpensiveQueries = true ) {
1105                 return $this->userCan( 'edit', $doExpensiveQueries );
1106         }
1107
1108         /**
1109          * Can $wgUser create this page?
1110          * @return boolean
1111          * @deprecated use userCan('create')
1112          */
1113         public function userCanCreate( $doExpensiveQueries = true ) {
1114                 return $this->userCan( 'create', $doExpensiveQueries );
1115         }
1116
1117         /**
1118          * Can $wgUser move this page?
1119          * @return boolean
1120          * @deprecated use userCan('move')
1121          */
1122         public function userCanMove( $doExpensiveQueries = true ) {
1123                 return $this->userCan( 'move', $doExpensiveQueries );
1124         }
1125
1126         /**
1127          * Would anybody with sufficient privileges be able to move this page?
1128          * Some pages just aren't movable.
1129          *
1130          * @return boolean
1131          */
1132         public function isMovable() {
1133                 return Namespace::isMovable( $this->getNamespace() )
1134                         && $this->getInterwiki() == '';
1135         }
1136
1137         /**
1138          * Can $wgUser read this page?
1139          * @return boolean
1140          * @todo fold these checks into userCan()
1141          */
1142         public function userCanRead() {
1143                 global $wgUser;
1144
1145                 $result = null;
1146                 wfRunHooks( 'userCan', array( &$this, &$wgUser, 'read', &$result ) );
1147                 if ( $result !== null ) {
1148                         return $result;
1149                 }
1150
1151                 if( $wgUser->isAllowed( 'read' ) ) {
1152                         return true;
1153                 } else {
1154                         global $wgWhitelistRead;
1155
1156                         /**
1157                          * Always grant access to the login page.
1158                          * Even anons need to be able to log in.
1159                         */
1160                         if( $this->isSpecial( 'Userlogin' ) || $this->isSpecial( 'Resetpass' ) ) {
1161                                 return true;
1162                         }
1163
1164                         /**
1165                          * Check for explicit whitelisting
1166                          */
1167                         $name = $this->getPrefixedText();
1168                         if( $wgWhitelistRead && in_array( $name, $wgWhitelistRead, true ) )
1169                                 return true;
1170
1171                         /**
1172                          * Old settings might have the title prefixed with
1173                          * a colon for main-namespace pages
1174                          */
1175                         if( $wgWhitelistRead && $this->getNamespace() == NS_MAIN ) {
1176                                 if( in_array( ':' . $name, $wgWhitelistRead ) )
1177                                         return true;
1178                         }
1179
1180                         /**
1181                          * If it's a special page, ditch the subpage bit
1182                          * and check again
1183                          */
1184                         if( $this->getNamespace() == NS_SPECIAL ) {
1185                                 $name = $this->getText();
1186                                 list( $name, $subpage ) = SpecialPage::resolveAliasWithSubpage( $name );
1187                                 $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
1188                                 if( in_array( $pure, $wgWhitelistRead, true ) )
1189                                         return true;
1190                         }
1191
1192                 }
1193                 return false;
1194         }
1195
1196         /**
1197          * Is this a talk page of some sort?
1198          * @return bool
1199          */
1200         public function isTalkPage() {
1201                 return Namespace::isTalk( $this->getNamespace() );
1202         }
1203
1204         /**
1205          * Is this a subpage?
1206          * @return bool
1207          */
1208         public function isSubpage() {
1209                 global $wgNamespacesWithSubpages;
1210
1211                 if( isset( $wgNamespacesWithSubpages[ $this->mNamespace ] ) ) {
1212                         return ( strpos( $this->getText(), '/' ) !== false && $wgNamespacesWithSubpages[ $this->mNamespace ] == true );
1213                 } else {
1214                         return false;
1215                 }
1216         }
1217
1218         /**
1219          * Is this a .css or .js subpage of a user page?
1220          * @return bool
1221          */
1222         public function isCssJsSubpage() {
1223                 return ( NS_USER == $this->mNamespace and preg_match("/\\/.*\\.(?:css|js)$/", $this->mTextform ) );
1224         }
1225         /**
1226          * Is this a *valid* .css or .js subpage of a user page?
1227          * Check that the corresponding skin exists
1228          */
1229         public function isValidCssJsSubpage() {
1230                 if ( $this->isCssJsSubpage() ) {
1231                         $skinNames = Skin::getSkinNames();
1232                         return array_key_exists( $this->getSkinFromCssJsSubpage(), $skinNames );
1233                 } else {
1234                         return false;
1235                 }
1236         }
1237         /**
1238          * Trim down a .css or .js subpage title to get the corresponding skin name
1239          */
1240         public function getSkinFromCssJsSubpage() {
1241                 $subpage = explode( '/', $this->mTextform );
1242                 $subpage = $subpage[ count( $subpage ) - 1 ];
1243                 return( str_replace( array( '.css', '.js' ), array( '', '' ), $subpage ) );
1244         }
1245         /**
1246          * Is this a .css subpage of a user page?
1247          * @return bool
1248          */
1249         public function isCssSubpage() {
1250                 return ( NS_USER == $this->mNamespace and preg_match("/\\/.*\\.css$/", $this->mTextform ) );
1251         }
1252         /**
1253          * Is this a .js subpage of a user page?
1254          * @return bool
1255          */
1256         public function isJsSubpage() {
1257                 return ( NS_USER == $this->mNamespace and preg_match("/\\/.*\\.js$/", $this->mTextform ) );
1258         }
1259         /**
1260          * Protect css/js subpages of user pages: can $wgUser edit
1261          * this page?
1262          *
1263          * @return boolean
1264          * @todo XXX: this might be better using restrictions
1265          */
1266         public function userCanEditCssJsSubpage() {
1267                 global $wgUser;
1268                 return ( $wgUser->isAllowed('editinterface') or preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1269         }
1270
1271         /**
1272          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
1273          *
1274          * @return bool If the page is subject to cascading restrictions.
1275          */
1276         public function isCascadeProtected() {
1277                 list( $sources, $restrictions ) = $this->getCascadeProtectionSources( false );
1278                 return ( $sources > 0 );
1279         }
1280
1281         /**
1282          * Cascading protection: Get the source of any cascading restrictions on this page.
1283          *
1284          * @param $get_pages bool Whether or not to retrieve the actual pages that the restrictions have come from.
1285          * @return array( mixed title array, restriction array)
1286          * 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.
1287          * The restriction array is an array of each type, each of which contains an array of unique groups
1288          */
1289         public function getCascadeProtectionSources( $get_pages = true ) {
1290                 global $wgEnableCascadingProtection, $wgRestrictionTypes;
1291
1292                 # Define our dimension of restrictions types
1293                 $pagerestrictions = array();
1294                 foreach( $wgRestrictionTypes as $action )
1295                         $pagerestrictions[$action] = array();
1296
1297                 if (!$wgEnableCascadingProtection)
1298                         return array( false, $pagerestrictions );
1299
1300                 if ( isset( $this->mCascadeSources ) && $get_pages ) {
1301                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
1302                 } else if ( isset( $this->mHasCascadingRestrictions ) && !$get_pages ) {
1303                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
1304                 }
1305
1306                 wfProfileIn( __METHOD__ );
1307
1308                 $dbr = wfGetDb( DB_SLAVE );
1309
1310                 if ( $this->getNamespace() == NS_IMAGE ) {
1311                         $tables = array ('imagelinks', 'page_restrictions');
1312                         $where_clauses = array(
1313                                 'il_to' => $this->getDBkey(),
1314                                 'il_from=pr_page',
1315                                 'pr_cascade' => 1 );
1316                 } else {
1317                         $tables = array ('templatelinks', 'page_restrictions');
1318                         $where_clauses = array(
1319                                 'tl_namespace' => $this->getNamespace(),
1320                                 'tl_title' => $this->getDBkey(),
1321                                 'tl_from=pr_page',
1322                                 'pr_cascade' => 1 );
1323                 }
1324
1325                 if ( $get_pages ) {
1326                         $cols = array('pr_page', 'page_namespace', 'page_title', 'pr_expiry', 'pr_type', 'pr_level' );
1327                         $where_clauses[] = 'page_id=pr_page';
1328                         $tables[] = 'page';
1329                 } else {
1330                         $cols = array( 'pr_expiry' );
1331                 }
1332
1333                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
1334
1335                 $sources = $get_pages ? array() : false;
1336                 $now = wfTimestampNow();
1337                 $purgeExpired = false;
1338
1339                 while( $row = $dbr->fetchObject( $res ) ) {
1340                         $expiry = Block::decodeExpiry( $row->pr_expiry );
1341                         if( $expiry > $now ) {
1342                                 if ($get_pages) {
1343                                         $page_id = $row->pr_page;
1344                                         $page_ns = $row->page_namespace;
1345                                         $page_title = $row->page_title;
1346                                         $sources[$page_id] = Title::makeTitle($page_ns, $page_title);
1347                                         # Add groups needed for each restriction type if its not already there
1348                                         # Make sure this restriction type still exists
1349                                         if ( isset($pagerestrictions[$row->pr_type]) && !in_array($row->pr_level, $pagerestrictions[$row->pr_type]) ) {
1350                                                 $pagerestrictions[$row->pr_type][]=$row->pr_level;
1351                                         }
1352                                 } else {
1353                                         $sources = true;
1354                                 }
1355                         } else {
1356                                 // Trigger lazy purge of expired restrictions from the db
1357                                 $purgeExpired = true;
1358                         }
1359                 }
1360                 if( $purgeExpired ) {
1361                         Title::purgeExpiredRestrictions();
1362                 }
1363
1364                 wfProfileOut( __METHOD__ );
1365
1366                 if ( $get_pages ) {
1367                         $this->mCascadeSources = $sources;
1368                         $this->mCascadingRestrictions = $pagerestrictions;
1369                 } else {
1370                         $this->mHasCascadingRestrictions = $sources;
1371                 }
1372
1373                 return array( $sources, $pagerestrictions );
1374         }
1375
1376         function areRestrictionsCascading() {
1377                 if (!$this->mRestrictionsLoaded) {
1378                         $this->loadRestrictions();
1379                 }
1380
1381                 return $this->mCascadeRestriction;
1382         }
1383
1384         /**
1385          * Loads a string into mRestrictions array
1386          * @param resource $res restrictions as an SQL result.
1387          */
1388         private function loadRestrictionsFromRow( $res, $oldFashionedRestrictions = NULL ) {
1389                 $dbr = wfGetDb( DB_SLAVE );
1390
1391                 $this->mRestrictions['edit'] = array();
1392                 $this->mRestrictions['move'] = array();
1393
1394                 # Backwards-compatibility: also load the restrictions from the page record (old format).
1395
1396                 if ( $oldFashionedRestrictions == NULL ) {
1397                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions', array( 'page_id' => $this->getArticleId() ), __METHOD__ );
1398                 }
1399
1400                 if ($oldFashionedRestrictions != '') {
1401
1402                         foreach( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
1403                                 $temp = explode( '=', trim( $restrict ) );
1404                                 if(count($temp) == 1) {
1405                                         // old old format should be treated as edit/move restriction
1406                                         $this->mRestrictions["edit"] = explode( ',', trim( $temp[0] ) );
1407                                         $this->mRestrictions["move"] = explode( ',', trim( $temp[0] ) );
1408                                 } else {
1409                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
1410                                 }
1411                         }
1412
1413                         $this->mOldRestrictions = true;
1414                         $this->mCascadeRestriction = false;
1415                         $this->mRestrictionsExpiry = Block::decodeExpiry('');
1416
1417                 }
1418
1419                 if( $dbr->numRows( $res ) ) {
1420                         # Current system - load second to make them override.
1421                         $now = wfTimestampNow();
1422                         $purgeExpired = false;
1423
1424                         while ($row = $dbr->fetchObject( $res ) ) {
1425                                 # Cycle through all the restrictions.
1426
1427                                 // This code should be refactored, now that it's being used more generally,
1428                                 // But I don't really see any harm in leaving it in Block for now -werdna
1429                                 $expiry = Block::decodeExpiry( $row->pr_expiry );
1430
1431                                 // Only apply the restrictions if they haven't expired!
1432                                 if ( !$expiry || $expiry > $now ) {
1433                                         $this->mRestrictionsExpiry = $expiry;
1434                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
1435
1436                                         $this->mCascadeRestriction |= $row->pr_cascade;
1437                                 } else {
1438                                         // Trigger a lazy purge of expired restrictions
1439                                         $purgeExpired = true;
1440                                 }
1441                         }
1442
1443                         if( $purgeExpired ) {
1444                                 Title::purgeExpiredRestrictions();
1445                         }
1446                 }
1447
1448                 $this->mRestrictionsLoaded = true;
1449         }
1450
1451         public function loadRestrictions( $oldFashionedRestrictions = NULL ) {
1452                 if( !$this->mRestrictionsLoaded ) {
1453                         $dbr = wfGetDB( DB_SLAVE );
1454
1455                         $res = $dbr->select( 'page_restrictions', '*',
1456                                 array ( 'pr_page' => $this->getArticleId() ), __METHOD__ );
1457
1458                         $this->loadRestrictionsFromRow( $res, $oldFashionedRestrictions );
1459                 }
1460         }
1461
1462         /**
1463          * Purge expired restrictions from the page_restrictions table
1464          */
1465         static function purgeExpiredRestrictions() {
1466                 $dbw = wfGetDB( DB_MASTER );
1467                 $dbw->delete( 'page_restrictions',
1468                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
1469                         __METHOD__ );
1470         }
1471
1472         /**
1473          * Accessor/initialisation for mRestrictions
1474          *
1475          * @param string $action action that permission needs to be checked for
1476          * @return array the array of groups allowed to edit this article
1477          */
1478         public function getRestrictions( $action ) {
1479                 if( $this->exists() ) {
1480                         if( !$this->mRestrictionsLoaded ) {
1481                                 $this->loadRestrictions();
1482                         }
1483                         return isset( $this->mRestrictions[$action] )
1484                                         ? $this->mRestrictions[$action]
1485                                         : array();
1486                 } else {
1487                         return array();
1488                 }
1489         }
1490
1491         /**
1492          * Is there a version of this page in the deletion archive?
1493          * @return int the number of archived revisions
1494          */
1495         public function isDeleted() {
1496                 $fname = 'Title::isDeleted';
1497                 if ( $this->getNamespace() < 0 ) {
1498                         $n = 0;
1499                 } else {
1500                         $dbr = wfGetDB( DB_SLAVE );
1501                         $n = $dbr->selectField( 'archive', 'COUNT(*)', array( 'ar_namespace' => $this->getNamespace(),
1502                                 'ar_title' => $this->getDBkey() ), $fname );
1503                         if( $this->getNamespace() == NS_IMAGE ) {
1504                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
1505                                         array( 'fa_name' => $this->getDBkey() ), $fname );
1506                         }
1507                 }
1508                 return (int)$n;
1509         }
1510
1511         /**
1512          * Get the article ID for this Title from the link cache,
1513          * adding it if necessary
1514          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select
1515          *      for update
1516          * @return int the ID
1517          */
1518         public function getArticleID( $flags = 0 ) {
1519                 $linkCache =& LinkCache::singleton();
1520                 if ( $flags & GAID_FOR_UPDATE ) {
1521                         $oldUpdate = $linkCache->forUpdate( true );
1522                         $this->mArticleID = $linkCache->addLinkObj( $this );
1523                         $linkCache->forUpdate( $oldUpdate );
1524                 } else {
1525                         if ( -1 == $this->mArticleID ) {
1526                                 $this->mArticleID = $linkCache->addLinkObj( $this );
1527                         }
1528                 }
1529                 return $this->mArticleID;
1530         }
1531
1532         public function getLatestRevID() {
1533                 if ($this->mLatestID !== false)
1534                         return $this->mLatestID;
1535
1536                 $db = wfGetDB(DB_SLAVE);
1537                 return $this->mLatestID = $db->selectField( 'revision',
1538                         "max(rev_id)",
1539                         array('rev_page' => $this->getArticleID()),
1540                         'Title::getLatestRevID' );
1541         }
1542
1543         /**
1544          * This clears some fields in this object, and clears any associated
1545          * keys in the "bad links" section of the link cache.
1546          *
1547          * - This is called from Article::insertNewArticle() to allow
1548          * loading of the new page_id. It's also called from
1549          * Article::doDeleteArticle()
1550          *
1551          * @param int $newid the new Article ID
1552          */
1553         public function resetArticleID( $newid ) {
1554                 $linkCache =& LinkCache::singleton();
1555                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
1556
1557                 if ( 0 == $newid ) { $this->mArticleID = -1; }
1558                 else { $this->mArticleID = $newid; }
1559                 $this->mRestrictionsLoaded = false;
1560                 $this->mRestrictions = array();
1561         }
1562
1563         /**
1564          * Updates page_touched for this page; called from LinksUpdate.php
1565          * @return bool true if the update succeded
1566          */
1567         public function invalidateCache() {
1568                 global $wgUseFileCache;
1569
1570                 if ( wfReadOnly() ) {
1571                         return;
1572                 }
1573
1574                 $dbw = wfGetDB( DB_MASTER );
1575                 $success = $dbw->update( 'page',
1576                         array( /* SET */
1577                                 'page_touched' => $dbw->timestamp()
1578                         ), array( /* WHERE */
1579                                 'page_namespace' => $this->getNamespace() ,
1580                                 'page_title' => $this->getDBkey()
1581                         ), 'Title::invalidateCache'
1582                 );
1583
1584                 if ($wgUseFileCache) {
1585                         $cache = new HTMLFileCache($this);
1586                         @unlink($cache->fileCacheName());
1587                 }
1588
1589                 return $success;
1590         }
1591
1592         /**
1593          * Prefix some arbitrary text with the namespace or interwiki prefix
1594          * of this object
1595          *
1596          * @param string $name the text
1597          * @return string the prefixed text
1598          * @private
1599          */
1600         /* private */ function prefix( $name ) {
1601                 $p = '';
1602                 if ( '' != $this->mInterwiki ) {
1603                         $p = $this->mInterwiki . ':';
1604                 }
1605                 if ( 0 != $this->mNamespace ) {
1606                         $p .= $this->getNsText() . ':';
1607                 }
1608                 return $p . $name;
1609         }
1610
1611         /**
1612          * Secure and split - main initialisation function for this object
1613          *
1614          * Assumes that mDbkeyform has been set, and is urldecoded
1615          * and uses underscores, but not otherwise munged.  This function
1616          * removes illegal characters, splits off the interwiki and
1617          * namespace prefixes, sets the other forms, and canonicalizes
1618          * everything.
1619          * @return bool true on success
1620          */
1621         private function secureAndSplit() {
1622                 global $wgContLang, $wgLocalInterwiki, $wgCapitalLinks;
1623
1624                 # Initialisation
1625                 static $rxTc = false;
1626                 if( !$rxTc ) {
1627                         # % is needed as well
1628                         $rxTc = '/[^' . Title::legalChars() . ']|%[0-9A-Fa-f]{2}/S';
1629                 }
1630
1631                 $this->mInterwiki = $this->mFragment = '';
1632                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
1633
1634                 $dbkey = $this->mDbkeyform;
1635
1636                 # Strip Unicode bidi override characters.
1637                 # Sometimes they slip into cut-n-pasted page titles, where the
1638                 # override chars get included in list displays.
1639                 $dbkey = str_replace( "\xE2\x80\x8E", '', $dbkey ); // 200E LEFT-TO-RIGHT MARK
1640                 $dbkey = str_replace( "\xE2\x80\x8F", '', $dbkey ); // 200F RIGHT-TO-LEFT MARK
1641
1642                 # Clean up whitespace
1643                 #
1644                 $dbkey = preg_replace( '/[ _]+/', '_', $dbkey );
1645                 $dbkey = trim( $dbkey, '_' );
1646
1647                 if ( '' == $dbkey ) {
1648                         return false;
1649                 }
1650
1651                 if( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
1652                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
1653                         return false;
1654                 }
1655
1656                 $this->mDbkeyform = $dbkey;
1657
1658                 # Initial colon indicates main namespace rather than specified default
1659                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
1660                 if ( ':' == $dbkey{0} ) {
1661                         $this->mNamespace = NS_MAIN;
1662                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
1663                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
1664                 }
1665
1666                 # Namespace or interwiki prefix
1667                 $firstPass = true;
1668                 do {
1669                         $m = array();
1670                         if ( preg_match( "/^(.+?)_*:_*(.*)$/S", $dbkey, $m ) ) {
1671                                 $p = $m[1];
1672                                 if ( $ns = $wgContLang->getNsIndex( $p )) {
1673                                         # Ordinary namespace
1674                                         $dbkey = $m[2];
1675                                         $this->mNamespace = $ns;
1676                                 } elseif( $this->getInterwikiLink( $p ) ) {
1677                                         if( !$firstPass ) {
1678                                                 # Can't make a local interwiki link to an interwiki link.
1679                                                 # That's just crazy!
1680                                                 return false;
1681                                         }
1682
1683                                         # Interwiki link
1684                                         $dbkey = $m[2];
1685                                         $this->mInterwiki = $wgContLang->lc( $p );
1686
1687                                         # Redundant interwiki prefix to the local wiki
1688                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
1689                                                 if( $dbkey == '' ) {
1690                                                         # Can't have an empty self-link
1691                                                         return false;
1692                                                 }
1693                                                 $this->mInterwiki = '';
1694                                                 $firstPass = false;
1695                                                 # Do another namespace split...
1696                                                 continue;
1697                                         }
1698
1699                                         # If there's an initial colon after the interwiki, that also
1700                                         # resets the default namespace
1701                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
1702                                                 $this->mNamespace = NS_MAIN;
1703                                                 $dbkey = substr( $dbkey, 1 );
1704                                         }
1705                                 }
1706                                 # If there's no recognized interwiki or namespace,
1707                                 # then let the colon expression be part of the title.
1708                         }
1709                         break;
1710                 } while( true );
1711
1712                 # We already know that some pages won't be in the database!
1713                 #
1714                 if ( '' != $this->mInterwiki || NS_SPECIAL == $this->mNamespace ) {
1715                         $this->mArticleID = 0;
1716                 }
1717                 $fragment = strstr( $dbkey, '#' );
1718                 if ( false !== $fragment ) {
1719                         $this->setFragment( $fragment );
1720                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
1721                         # remove whitespace again: prevents "Foo_bar_#"
1722                         # becoming "Foo_bar_"
1723                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
1724                 }
1725
1726                 # Reject illegal characters.
1727                 #
1728                 if( preg_match( $rxTc, $dbkey ) ) {
1729                         return false;
1730                 }
1731
1732                 /**
1733                  * Pages with "/./" or "/../" appearing in the URLs will
1734                  * often be unreachable due to the way web browsers deal
1735                  * with 'relative' URLs. Forbid them explicitly.
1736                  */
1737                 if ( strpos( $dbkey, '.' ) !== false &&
1738                      ( $dbkey === '.' || $dbkey === '..' ||
1739                        strpos( $dbkey, './' ) === 0  ||
1740                        strpos( $dbkey, '../' ) === 0 ||
1741                        strpos( $dbkey, '/./' ) !== false ||
1742                        strpos( $dbkey, '/../' ) !== false ) )
1743                 {
1744                         return false;
1745                 }
1746
1747                 /**
1748                  * Magic tilde sequences? Nu-uh!
1749                  */
1750                 if( strpos( $dbkey, '~~~' ) !== false ) {
1751                         return false;
1752                 }
1753
1754                 /**
1755                  * Limit the size of titles to 255 bytes.
1756                  * This is typically the size of the underlying database field.
1757                  * We make an exception for special pages, which don't need to be stored
1758                  * in the database, and may edge over 255 bytes due to subpage syntax
1759                  * for long titles, e.g. [[Special:Block/Long name]]
1760                  */
1761                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
1762                   strlen( $dbkey ) > 512 )
1763                 {
1764                         return false;
1765                 }
1766
1767                 /**
1768                  * Normally, all wiki links are forced to have
1769                  * an initial capital letter so [[foo]] and [[Foo]]
1770                  * point to the same place.
1771                  *
1772                  * Don't force it for interwikis, since the other
1773                  * site might be case-sensitive.
1774                  */
1775                 $this->mUserCaseDBKey = $dbkey;
1776                 if( $wgCapitalLinks && $this->mInterwiki == '') {
1777                         $dbkey = $wgContLang->ucfirst( $dbkey );
1778                 }
1779
1780                 /**
1781                  * Can't make a link to a namespace alone...
1782                  * "empty" local links can only be self-links
1783                  * with a fragment identifier.
1784                  */
1785                 if( $dbkey == '' &&
1786                         $this->mInterwiki == '' &&
1787                         $this->mNamespace != NS_MAIN ) {
1788                         return false;
1789                 }
1790
1791                 // Any remaining initial :s are illegal.
1792                 if ( $dbkey !== '' && ':' == $dbkey{0} ) {
1793                         return false;
1794                 }
1795
1796                 # Fill fields
1797                 $this->mDbkeyform = $dbkey;
1798                 $this->mUrlform = wfUrlencode( $dbkey );
1799
1800                 $this->mTextform = str_replace( '_', ' ', $dbkey );
1801
1802                 return true;
1803         }
1804
1805         /**
1806          * Set the fragment for this title
1807          * This is kind of bad, since except for this rarely-used function, Title objects
1808          * are immutable. The reason this is here is because it's better than setting the
1809          * members directly, which is what Linker::formatComment was doing previously.
1810          *
1811          * @param string $fragment text
1812          * @todo clarify whether access is supposed to be public (was marked as "kind of public")
1813          */
1814         public function setFragment( $fragment ) {
1815                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
1816         }
1817
1818         /**
1819          * Get a Title object associated with the talk page of this article
1820          * @return Title the object for the talk page
1821          */
1822         public function getTalkPage() {
1823                 return Title::makeTitle( Namespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1824         }
1825
1826         /**
1827          * Get a title object associated with the subject page of this
1828          * talk page
1829          *
1830          * @return Title the object for the subject page
1831          */
1832         public function getSubjectPage() {
1833                 return Title::makeTitle( Namespace::getSubject( $this->getNamespace() ), $this->getDBkey() );
1834         }
1835
1836         /**
1837          * Get an array of Title objects linking to this Title
1838          * Also stores the IDs in the link cache.
1839          *
1840          * WARNING: do not use this function on arbitrary user-supplied titles!
1841          * On heavily-used templates it will max out the memory.
1842          *
1843          * @param string $options may be FOR UPDATE
1844          * @return array the Title objects linking here
1845          */
1846         public function getLinksTo( $options = '', $table = 'pagelinks', $prefix = 'pl' ) {
1847                 $linkCache =& LinkCache::singleton();
1848
1849                 if ( $options ) {
1850                         $db = wfGetDB( DB_MASTER );
1851                 } else {
1852                         $db = wfGetDB( DB_SLAVE );
1853                 }
1854
1855                 $res = $db->select( array( 'page', $table ),
1856                         array( 'page_namespace', 'page_title', 'page_id' ),
1857                         array(
1858                                 "{$prefix}_from=page_id",
1859                                 "{$prefix}_namespace" => $this->getNamespace(),
1860                                 "{$prefix}_title"     => $this->getDbKey() ),
1861                         'Title::getLinksTo',
1862                         $options );
1863
1864                 $retVal = array();
1865                 if ( $db->numRows( $res ) ) {
1866                         while ( $row = $db->fetchObject( $res ) ) {
1867                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
1868                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj );
1869                                         $retVal[] = $titleObj;
1870                                 }
1871                         }
1872                 }
1873                 $db->freeResult( $res );
1874                 return $retVal;
1875         }
1876
1877         /**
1878          * Get an array of Title objects using this Title as a template
1879          * Also stores the IDs in the link cache.
1880          *
1881          * WARNING: do not use this function on arbitrary user-supplied titles!
1882          * On heavily-used templates it will max out the memory.
1883          *
1884          * @param string $options may be FOR UPDATE
1885          * @return array the Title objects linking here
1886          */
1887         public function getTemplateLinksTo( $options = '' ) {
1888                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
1889         }
1890
1891         /**
1892          * Get an array of Title objects referring to non-existent articles linked from this page
1893          *
1894          * @param string $options may be FOR UPDATE
1895          * @return array the Title objects
1896          */
1897         public function getBrokenLinksFrom( $options = '' ) {
1898                 if ( $options ) {
1899                         $db = wfGetDB( DB_MASTER );
1900                 } else {
1901                         $db = wfGetDB( DB_SLAVE );
1902                 }
1903
1904                 $res = $db->safeQuery(
1905                           "SELECT pl_namespace, pl_title
1906                              FROM !
1907                         LEFT JOIN !
1908                                ON pl_namespace=page_namespace
1909                               AND pl_title=page_title
1910                             WHERE pl_from=?
1911                               AND page_namespace IS NULL
1912                                   !",
1913                         $db->tableName( 'pagelinks' ),
1914                         $db->tableName( 'page' ),
1915                         $this->getArticleId(),
1916                         $options );
1917
1918                 $retVal = array();
1919                 if ( $db->numRows( $res ) ) {
1920                         while ( $row = $db->fetchObject( $res ) ) {
1921                                 $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
1922                         }
1923                 }
1924                 $db->freeResult( $res );
1925                 return $retVal;
1926         }
1927
1928
1929         /**
1930          * Get a list of URLs to purge from the Squid cache when this
1931          * page changes
1932          *
1933          * @return array the URLs
1934          */
1935         public function getSquidURLs() {
1936                 global $wgContLang;
1937
1938                 $urls = array(
1939                         $this->getInternalURL(),
1940                         $this->getInternalURL( 'action=history' )
1941                 );
1942
1943                 // purge variant urls as well
1944                 if($wgContLang->hasVariants()){
1945                         $variants = $wgContLang->getVariants();
1946                         foreach($variants as $vCode){
1947                                 if($vCode==$wgContLang->getCode()) continue; // we don't want default variant
1948                                 $urls[] = $this->getInternalURL('',$vCode);
1949                         }
1950                 }
1951
1952                 return $urls;
1953         }
1954
1955         public function purgeSquid() {
1956                 global $wgUseSquid;
1957                 if ( $wgUseSquid ) {
1958                         $urls = $this->getSquidURLs();
1959                         $u = new SquidUpdate( $urls );
1960                         $u->doUpdate();
1961                 }
1962         }
1963
1964         /**
1965          * Move this page without authentication
1966          * @param Title &$nt the new page Title
1967          */
1968         public function moveNoAuth( &$nt ) {
1969                 return $this->moveTo( $nt, false );
1970         }
1971
1972         /**
1973          * Check whether a given move operation would be valid.
1974          * Returns true if ok, or a message key string for an error message
1975          * if invalid. (Scarrrrry ugly interface this.)
1976          * @param Title &$nt the new title
1977          * @param bool $auth indicates whether $wgUser's permissions
1978          *      should be checked
1979          * @return mixed true on success, message name on failure
1980          */
1981         public function isValidMoveOperation( &$nt, $auth = true ) {
1982                 if( !$this or !$nt ) {
1983                         return 'badtitletext';
1984                 }
1985                 if( $this->equals( $nt ) ) {
1986                         return 'selfmove';
1987                 }
1988                 if( !$this->isMovable() || !$nt->isMovable() ) {
1989                         return 'immobile_namespace';
1990                 }
1991
1992                 $oldid = $this->getArticleID();
1993                 $newid = $nt->getArticleID();
1994
1995                 if ( strlen( $nt->getDBkey() ) < 1 ) {
1996                         return 'articleexists';
1997                 }
1998                 if ( ( '' == $this->getDBkey() ) ||
1999                          ( !$oldid ) ||
2000                      ( '' == $nt->getDBkey() ) ) {
2001                         return 'badarticleerror';
2002                 }
2003
2004                 if ( $auth && (
2005                                 !$this->userCan( 'edit' ) || !$nt->userCan( 'edit' ) ||
2006                                 !$this->userCan( 'move' ) || !$nt->userCan( 'move' ) ) ) {
2007                         return 'protectedpage';
2008                 }
2009
2010                 # The move is allowed only if (1) the target doesn't exist, or
2011                 # (2) the target is a redirect to the source, and has no history
2012                 # (so we can undo bad moves right after they're done).
2013
2014                 if ( 0 != $newid ) { # Target exists; check for validity
2015                         if ( ! $this->isValidMoveTarget( $nt ) ) {
2016                                 return 'articleexists';
2017                         }
2018                 }
2019                 return true;
2020         }
2021
2022         /**
2023          * Move a title to a new location
2024          * @param Title &$nt the new title
2025          * @param bool $auth indicates whether $wgUser's permissions
2026          *      should be checked
2027          * @return mixed true on success, message name on failure
2028          */
2029         public function moveTo( &$nt, $auth = true, $reason = '' ) {
2030                 $err = $this->isValidMoveOperation( $nt, $auth );
2031                 if( is_string( $err ) ) {
2032                         return $err;
2033                 }
2034
2035                 $pageid = $this->getArticleID();
2036                 if( $nt->exists() ) {
2037                         $this->moveOverExistingRedirect( $nt, $reason );
2038                         $pageCountChange = 0;
2039                 } else { # Target didn't exist, do normal move.
2040                         $this->moveToNewTitle( $nt, $reason );
2041                         $pageCountChange = 1;
2042                 }
2043                 $redirid = $this->getArticleID();
2044
2045                 # Fixing category links (those without piped 'alternate' names) to be sorted under the new title
2046                 $dbw = wfGetDB( DB_MASTER );
2047                 $categorylinks = $dbw->tableName( 'categorylinks' );
2048                 $sql = "UPDATE $categorylinks SET cl_sortkey=" . $dbw->addQuotes( $nt->getPrefixedText() ) .
2049                         " WHERE cl_from=" . $dbw->addQuotes( $pageid ) .
2050                         " AND cl_sortkey=" . $dbw->addQuotes( $this->getPrefixedText() );
2051                 $dbw->query( $sql, 'SpecialMovepage::doSubmit' );
2052
2053                 # Update watchlists
2054
2055                 $oldnamespace = $this->getNamespace() & ~1;
2056                 $newnamespace = $nt->getNamespace() & ~1;
2057                 $oldtitle = $this->getDBkey();
2058                 $newtitle = $nt->getDBkey();
2059
2060                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
2061                         WatchedItem::duplicateEntries( $this, $nt );
2062                 }
2063
2064                 # Update search engine
2065                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
2066                 $u->doUpdate();
2067                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
2068                 $u->doUpdate();
2069
2070                 # Update site_stats
2071                 if( $this->isContentPage() && !$nt->isContentPage() ) {
2072                         # No longer a content page
2073                         # Not viewed, edited, removing
2074                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange );
2075                 } elseif( !$this->isContentPage() && $nt->isContentPage() ) {
2076                         # Now a content page
2077                         # Not viewed, edited, adding
2078                         $u = new SiteStatsUpdate( 0, 1, +1, $pageCountChange );
2079                 } elseif( $pageCountChange ) {
2080                         # Redirect added
2081                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
2082                 } else {
2083                         # Nothing special
2084                         $u = false;
2085                 }
2086                 if( $u )
2087                         $u->doUpdate();
2088
2089                 global $wgUser;
2090                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
2091                 return true;
2092         }
2093
2094         /**
2095          * Move page to a title which is at present a redirect to the
2096          * source page
2097          *
2098          * @param Title &$nt the page to move to, which should currently
2099          *      be a redirect
2100          */
2101         private function moveOverExistingRedirect( &$nt, $reason = '' ) {
2102                 global $wgUseSquid;
2103                 $fname = 'Title::moveOverExistingRedirect';
2104                 $comment = wfMsgForContent( '1movedto2_redir', $this->getPrefixedText(), $nt->getPrefixedText() );
2105
2106                 if ( $reason ) {
2107                         $comment .= ": $reason";
2108                 }
2109
2110                 $now = wfTimestampNow();
2111                 $newid = $nt->getArticleID();
2112                 $oldid = $this->getArticleID();
2113                 $dbw = wfGetDB( DB_MASTER );
2114                 $linkCache =& LinkCache::singleton();
2115
2116                 # Delete the old redirect. We don't save it to history since
2117                 # by definition if we've got here it's rather uninteresting.
2118                 # We have to remove it so that the next step doesn't trigger
2119                 # a conflict on the unique namespace+title index...
2120                 $dbw->delete( 'page', array( 'page_id' => $newid ), $fname );
2121
2122                 # Save a null revision in the page's history notifying of the move
2123                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
2124                 $nullRevId = $nullRevision->insertOn( $dbw );
2125
2126                 # Change the name of the target page:
2127                 $dbw->update( 'page',
2128                         /* SET */ array(
2129                                 'page_touched'   => $dbw->timestamp($now),
2130                                 'page_namespace' => $nt->getNamespace(),
2131                                 'page_title'     => $nt->getDBkey(),
2132                                 'page_latest'    => $nullRevId,
2133                         ),
2134                         /* WHERE */ array( 'page_id' => $oldid ),
2135                         $fname
2136                 );
2137                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
2138
2139                 # Recreate the redirect, this time in the other direction.
2140                 $mwRedir = MagicWord::get( 'redirect' );
2141                 $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
2142                 $redirectArticle = new Article( $this );
2143                 $newid = $redirectArticle->insertOn( $dbw );
2144                 $redirectRevision = new Revision( array(
2145                         'page'    => $newid,
2146                         'comment' => $comment,
2147                         'text'    => $redirectText ) );
2148                 $redirectRevision->insertOn( $dbw );
2149                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
2150                 $linkCache->clearLink( $this->getPrefixedDBkey() );
2151
2152                 # Log the move
2153                 $log = new LogPage( 'move' );
2154                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText() ) );
2155
2156                 # Now, we record the link from the redirect to the new title.
2157                 # It should have no other outgoing links...
2158                 $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), $fname );
2159                 $dbw->insert( 'pagelinks',
2160                         array(
2161                                 'pl_from'      => $newid,
2162                                 'pl_namespace' => $nt->getNamespace(),
2163                                 'pl_title'     => $nt->getDbKey() ),
2164                         $fname );
2165
2166                 # Purge squid
2167                 if ( $wgUseSquid ) {
2168                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
2169                         $u = new SquidUpdate( $urls );
2170                         $u->doUpdate();
2171                 }
2172         }
2173
2174         /**
2175          * Move page to non-existing title.
2176          * @param Title &$nt the new Title
2177          */
2178         private function moveToNewTitle( &$nt, $reason = '' ) {
2179                 global $wgUseSquid;
2180                 $fname = 'MovePageForm::moveToNewTitle';
2181                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
2182                 if ( $reason ) {
2183                         $comment .= ": $reason";
2184                 }
2185
2186                 $newid = $nt->getArticleID();
2187                 $oldid = $this->getArticleID();
2188                 $dbw = wfGetDB( DB_MASTER );
2189                 $now = $dbw->timestamp();
2190                 $linkCache =& LinkCache::singleton();
2191
2192                 # Save a null revision in the page's history notifying of the move
2193                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
2194                 $nullRevId = $nullRevision->insertOn( $dbw );
2195
2196                 # Rename cur entry
2197                 $dbw->update( 'page',
2198                         /* SET */ array(
2199                                 'page_touched'   => $now,
2200                                 'page_namespace' => $nt->getNamespace(),
2201                                 'page_title'     => $nt->getDBkey(),
2202                                 'page_latest'    => $nullRevId,
2203                         ),
2204                         /* WHERE */ array( 'page_id' => $oldid ),
2205                         $fname
2206                 );
2207
2208                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
2209
2210                 # Insert redirect
2211                 $mwRedir = MagicWord::get( 'redirect' );
2212                 $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
2213                 $redirectArticle = new Article( $this );
2214                 $newid = $redirectArticle->insertOn( $dbw );
2215                 $redirectRevision = new Revision( array(
2216                         'page'    => $newid,
2217                         'comment' => $comment,
2218                         'text'    => $redirectText ) );
2219                 $redirectRevision->insertOn( $dbw );
2220                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
2221                 $linkCache->clearLink( $this->getPrefixedDBkey() );
2222
2223                 # Log the move
2224                 $log = new LogPage( 'move' );
2225                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText()) );
2226
2227                 # Purge caches as per article creation
2228                 Article::onArticleCreate( $nt );
2229
2230                 # Record the just-created redirect's linking to the page
2231                 $dbw->insert( 'pagelinks',
2232                         array(
2233                                 'pl_from'      => $newid,
2234                                 'pl_namespace' => $nt->getNamespace(),
2235                                 'pl_title'     => $nt->getDBkey() ),
2236                         $fname );
2237
2238                 # Purge old title from squid
2239                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
2240                 $this->purgeSquid();
2241         }
2242
2243         /**
2244          * Checks if $this can be moved to a given Title
2245          * - Selects for update, so don't call it unless you mean business
2246          *
2247          * @param Title &$nt the new title to check
2248          */
2249         public function isValidMoveTarget( $nt ) {
2250
2251                 $fname = 'Title::isValidMoveTarget';
2252                 $dbw = wfGetDB( DB_MASTER );
2253
2254                 # Is it a redirect?
2255                 $id  = $nt->getArticleID();
2256                 $obj = $dbw->selectRow( array( 'page', 'revision', 'text'),
2257                         array( 'page_is_redirect','old_text','old_flags' ),
2258                         array( 'page_id' => $id, 'page_latest=rev_id', 'rev_text_id=old_id' ),
2259                         $fname, 'FOR UPDATE' );
2260
2261                 if ( !$obj || 0 == $obj->page_is_redirect ) {
2262                         # Not a redirect
2263                         wfDebug( __METHOD__ . ": not a redirect\n" );
2264                         return false;
2265                 }
2266                 $text = Revision::getRevisionText( $obj );
2267
2268                 # Does the redirect point to the source?
2269                 # Or is it a broken self-redirect, usually caused by namespace collisions?
2270                 $m = array();
2271                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
2272                         $redirTitle = Title::newFromText( $m[1] );
2273                         if( !is_object( $redirTitle ) ||
2274                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
2275                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
2276                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
2277                                 return false;
2278                         }
2279                 } else {
2280                         # Fail safe
2281                         wfDebug( __METHOD__ . ": failsafe\n" );
2282                         return false;
2283                 }
2284
2285                 # Does the article have a history?
2286                 $row = $dbw->selectRow( array( 'page', 'revision'),
2287                         array( 'rev_id' ),
2288                         array( 'page_namespace' => $nt->getNamespace(),
2289                                 'page_title' => $nt->getDBkey(),
2290                                 'page_id=rev_page AND page_latest != rev_id'
2291                         ), $fname, 'FOR UPDATE'
2292                 );
2293
2294                 # Return true if there was no history
2295                 return $row === false;
2296         }
2297
2298         /**
2299          * Get categories to which this Title belongs and return an array of
2300          * categories' names.
2301          *
2302          * @return array an array of parents in the form:
2303          *      $parent => $currentarticle
2304          */
2305         public function getParentCategories() {
2306                 global $wgContLang;
2307
2308                 $titlekey = $this->getArticleId();
2309                 $dbr = wfGetDB( DB_SLAVE );
2310                 $categorylinks = $dbr->tableName( 'categorylinks' );
2311
2312                 # NEW SQL
2313                 $sql = "SELECT * FROM $categorylinks"
2314                      ." WHERE cl_from='$titlekey'"
2315                          ." AND cl_from <> '0'"
2316                          ." ORDER BY cl_sortkey";
2317
2318                 $res = $dbr->query ( $sql ) ;
2319
2320                 if($dbr->numRows($res) > 0) {
2321                         while ( $x = $dbr->fetchObject ( $res ) )
2322                                 //$data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to);
2323                                 $data[$wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to] = $this->getFullText();
2324                         $dbr->freeResult ( $res ) ;
2325                 } else {
2326                         $data = '';
2327                 }
2328                 return $data;
2329         }
2330
2331         /**
2332          * Get a tree of parent categories
2333          * @param array $children an array with the children in the keys, to check for circular refs
2334          * @return array
2335          */
2336         public function getParentCategoryTree( $children = array() ) {
2337                 $parents = $this->getParentCategories();
2338
2339                 if($parents != '') {
2340                         foreach($parents as $parent => $current) {
2341                                 if ( array_key_exists( $parent, $children ) ) {
2342                                         # Circular reference
2343                                         $stack[$parent] = array();
2344                                 } else {
2345                                         $nt = Title::newFromText($parent);
2346                                         if ( $nt ) {
2347                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array($parent => 1) );
2348                                         }
2349                                 }
2350                         }
2351                         return $stack;
2352                 } else {
2353                         return array();
2354                 }
2355         }
2356
2357
2358         /**
2359          * Get an associative array for selecting this title from
2360          * the "page" table
2361          *
2362          * @return array
2363          */
2364         public function pageCond() {
2365                 return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
2366         }
2367
2368         /**
2369          * Get the revision ID of the previous revision
2370          *
2371          * @param integer $revision  Revision ID. Get the revision that was before this one.
2372          * @return integer $oldrevision|false
2373          */
2374         public function getPreviousRevisionID( $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 DESC' );
2379         }
2380
2381         /**
2382          * Get the revision ID of the next revision
2383          *
2384          * @param integer $revision  Revision ID. Get the revision that was after this one.
2385          * @return integer $oldrevision|false
2386          */
2387         public function getNextRevisionID( $revision ) {
2388                 $dbr = wfGetDB( DB_SLAVE );
2389                 return $dbr->selectField( 'revision', 'rev_id',
2390                         'rev_page=' . intval( $this->getArticleId() ) .
2391                         ' AND rev_id>' . intval( $revision ) . ' ORDER BY rev_id' );
2392         }
2393
2394         /**
2395          * Get the number of revisions between the given revision IDs.
2396          *
2397          * @param integer $old  Revision ID.
2398          * @param integer $new  Revision ID.
2399          * @return integer  Number of revisions between these IDs.
2400          */
2401         public function countRevisionsBetween( $old, $new ) {
2402                 $dbr = wfGetDB( DB_SLAVE );
2403                 return $dbr->selectField( 'revision', 'count(*)',
2404                         'rev_page = ' . intval( $this->getArticleId() ) .
2405                         ' AND rev_id > ' . intval( $old ) .
2406                         ' AND rev_id < ' . intval( $new ) );
2407         }
2408
2409         /**
2410          * Compare with another title.
2411          *
2412          * @param Title $title
2413          * @return bool
2414          */
2415         public function equals( $title ) {
2416                 // Note: === is necessary for proper matching of number-like titles.
2417                 return $this->getInterwiki() === $title->getInterwiki()
2418                         && $this->getNamespace() == $title->getNamespace()
2419                         && $this->getDbkey() === $title->getDbkey();
2420         }
2421
2422         /**
2423          * Check if page exists
2424          * @return bool
2425          */
2426         public function exists() {
2427                 return $this->getArticleId() != 0;
2428         }
2429
2430         /**
2431          * Should a link should be displayed as a known link, just based on its title?
2432          *
2433          * Currently, a self-link with a fragment and special pages are in
2434          * this category. System messages that have defined default values are also
2435          * always known.
2436          */
2437         public function isAlwaysKnown() {
2438                 return ( $this->isExternal() ||
2439                          ( 0 == $this->mNamespace && "" == $this->mDbkeyform ) ||
2440                          ( NS_MEDIAWIKI == $this->mNamespace && wfMsgWeirdKey( $this->mDbkeyform ) ) );
2441         }
2442
2443         /**
2444          * Update page_touched timestamps and send squid purge messages for
2445          * pages linking to this title. May be sent to the job queue depending
2446          * on the number of links. Typically called on create and delete.
2447          */
2448         public function touchLinks() {
2449                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
2450                 $u->doUpdate();
2451
2452                 if ( $this->getNamespace() == NS_CATEGORY ) {
2453                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
2454                         $u->doUpdate();
2455                 }
2456         }
2457
2458         /**
2459          * Get the last touched timestamp
2460          */
2461         public function getTouched() {
2462                 $dbr = wfGetDB( DB_SLAVE );
2463                 $touched = $dbr->selectField( 'page', 'page_touched',
2464                         array(
2465                                 'page_namespace' => $this->getNamespace(),
2466                                 'page_title' => $this->getDBkey()
2467                         ), __METHOD__
2468                 );
2469                 return $touched;
2470         }
2471
2472         public function trackbackURL() {
2473                 global $wgTitle, $wgScriptPath, $wgServer;
2474
2475                 return "$wgServer$wgScriptPath/trackback.php?article="
2476                         . htmlspecialchars(urlencode($wgTitle->getPrefixedDBkey()));
2477         }
2478
2479         public function trackbackRDF() {
2480                 $url = htmlspecialchars($this->getFullURL());
2481                 $title = htmlspecialchars($this->getText());
2482                 $tburl = $this->trackbackURL();
2483
2484                 return "
2485 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
2486          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
2487          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
2488 <rdf:Description
2489    rdf:about=\"$url\"
2490    dc:identifier=\"$url\"
2491    dc:title=\"$title\"
2492    trackback:ping=\"$tburl\" />
2493 </rdf:RDF>";
2494         }
2495
2496         /**
2497          * Generate strings used for xml 'id' names in monobook tabs
2498          * @return string
2499          */
2500         public function getNamespaceKey() {
2501                 global $wgContLang;
2502                 switch ($this->getNamespace()) {
2503                         case NS_MAIN:
2504                         case NS_TALK:
2505                                 return 'nstab-main';
2506                         case NS_USER:
2507                         case NS_USER_TALK:
2508                                 return 'nstab-user';
2509                         case NS_MEDIA:
2510                                 return 'nstab-media';
2511                         case NS_SPECIAL:
2512                                 return 'nstab-special';
2513                         case NS_PROJECT:
2514                         case NS_PROJECT_TALK:
2515                                 return 'nstab-project';
2516                         case NS_IMAGE:
2517                         case NS_IMAGE_TALK:
2518                                 return 'nstab-image';
2519                         case NS_MEDIAWIKI:
2520                         case NS_MEDIAWIKI_TALK:
2521                                 return 'nstab-mediawiki';
2522                         case NS_TEMPLATE:
2523                         case NS_TEMPLATE_TALK:
2524                                 return 'nstab-template';
2525                         case NS_HELP:
2526                         case NS_HELP_TALK:
2527                                 return 'nstab-help';
2528                         case NS_CATEGORY:
2529                         case NS_CATEGORY_TALK:
2530                                 return 'nstab-category';
2531                         default:
2532                                 return 'nstab-' . $wgContLang->lc( $this->getSubjectNsText() );
2533                 }
2534         }
2535
2536         /**
2537          * Returns true if this title resolves to the named special page
2538          * @param string $name The special page name
2539          */
2540         public function isSpecial( $name ) {
2541                 if ( $this->getNamespace() == NS_SPECIAL ) {
2542                         list( $thisName, /* $subpage */ ) = SpecialPage::resolveAliasWithSubpage( $this->getDBkey() );
2543                         if ( $name == $thisName ) {
2544                                 return true;
2545                         }
2546                 }
2547                 return false;
2548         }
2549
2550         /**
2551          * If the Title refers to a special page alias which is not the local default,
2552          * returns a new Title which points to the local default. Otherwise, returns $this.
2553          */
2554         public function fixSpecialName() {
2555                 if ( $this->getNamespace() == NS_SPECIAL ) {
2556                         $canonicalName = SpecialPage::resolveAlias( $this->mDbkeyform );
2557                         if ( $canonicalName ) {
2558                                 $localName = SpecialPage::getLocalNameFor( $canonicalName );
2559                                 if ( $localName != $this->mDbkeyform ) {
2560                                         return Title::makeTitle( NS_SPECIAL, $localName );
2561                                 }
2562                         }
2563                 }
2564                 return $this;
2565         }
2566
2567         /**
2568          * Is this Title in a namespace which contains content?
2569          * In other words, is this a content page, for the purposes of calculating
2570          * statistics, etc?
2571          *
2572          * @return bool
2573          */
2574         public function isContentPage() {
2575                 return Namespace::isContent( $this->getNamespace() );
2576         }
2577
2578 }
2579
2580 ?>