includes/Title.php

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