includes/Title.php

   1 <?php
   2 /**
   3  * See title.txt
   4  * @file
   5  */
   6
   7 /**
   8  * @todo:  determine if it is really necessary to load this.  Appears to be left over from pre-autoloader versions, and
   9  *   is only really needed to provide access to constant UTF8_REPLACEMENT, which actually resides in UtfNormalDefines.php
  10  *   and is loaded by UtfNormalUtil.php, which is loaded by UtfNormal.php.
  11  */
  12 if ( !class_exists( 'UtfNormal' ) ) {
  13         require_once( dirname( __FILE__ ) . '/normal/UtfNormal.php' );
  14 }
  15
  16 /**
  17  * Represents a title within MediaWiki.
  18  * Optionally may contain an interwiki designation or namespace.
  19  * @note This class can fetch various kinds of data from the database;
  20  *       however, it does so inefficiently.
  21  *
  22  * @internal documentation reviewed 15 Mar 2010
  23  */
  24 class Title {
  25         /** @name Static cache variables */
  26         // @{
  27         static private $titleCache = array();
  28         // @}
  29
  30         /**
  31          * Title::newFromText maintains a cache to avoid expensive re-normalization of
  32          * commonly used titles. On a batch operation this can become a memory leak
  33          * if not bounded. After hitting this many titles reset the cache.
  34          */
  35         const CACHE_MAX = 1000;
  36
  37         /**
  38          * Used to be GAID_FOR_UPDATE define. Used with getArticleId() and friends
  39          * to use the master DB
  40          */
  41         const GAID_FOR_UPDATE = 1;
  42
  43
  44         /**
  45          * @name Private member variables
  46          * Please use the accessor functions instead.
  47          * @private
  48          */
  49         // @{
  50
  51         var $mTextform = '';              // /< Text form (spaces not underscores) of the main part
  52         var $mUrlform = '';               // /< URL-encoded form of the main part
  53         var $mDbkeyform = '';             // /< Main part with underscores
  54         var $mUserCaseDBKey;              // /< DB key with the initial letter in the case specified by the user
  55         var $mNamespace = NS_MAIN;        // /< Namespace index, i.e. one of the NS_xxxx constants
  56         var $mInterwiki = '';             // /< Interwiki prefix (or null string)
  57         var $mFragment;                   // /< Title fragment (i.e. the bit after the #)
  58         var $mArticleID = -1;             // /< Article ID, fetched from the link cache on demand
  59         var $mLatestID = false;           // /< ID of most recent revision
  60         var $mRestrictions = array();     // /< Array of groups allowed to edit this article
  61         var $mOldRestrictions = false;
  62         var $mCascadeRestriction;         ///< Cascade restrictions on this page to included templates and images?
  63         var $mCascadingRestrictions;      // Caching the results of getCascadeProtectionSources
  64         var $mRestrictionsExpiry = array(); ///< When do the restrictions on this page expire?
  65         var $mHasCascadingRestrictions;   ///< Are cascading restrictions in effect on this page?
  66         var $mCascadeSources;             ///< Where are the cascading restrictions coming from on this page?
  67         var $mRestrictionsLoaded = false; ///< Boolean for initialisation on demand
  68         var $mPrefixedText;               ///< Text form including namespace/interwiki, initialised on demand
  69         var $mTitleProtection;            ///< Cached value of getTitleProtection
  70         # Don't change the following default, NS_MAIN is hardcoded in several
  71         # places.  See bug 696.
  72         var $mDefaultNamespace = NS_MAIN; // /< Namespace index when there is no namespace
  73                                           # Zero except in {{transclusion}} tags
  74         var $mWatched = null;             // /< Is $wgUser watching this page? null if unfilled, accessed through userIsWatching()
  75         var $mLength = -1;                // /< The page length, 0 for special pages
  76         var $mRedirect = null;            // /< Is the article at this title a redirect?
  77         var $mNotificationTimestamp = array(); // /< Associative array of user ID -> timestamp/false
  78         var $mBacklinkCache = null;       // /< Cache of links to this title
  79         // @}
  80
  81
  82         /**
  83          * Constructor
  84          * @private
  85          */
  86         /* private */ function __construct() { }
  87
  88         /**
  89          * Create a new Title from a prefixed DB key
  90          *
  91          * @param $key \type{\string} The database key, which has underscores
  92          *      instead of spaces, possibly including namespace and
  93          *      interwiki prefixes
  94          * @return \type{Title} the new object, or NULL on an error
  95          */
  96         public static function newFromDBkey( $key ) {
  97                 $t = new Title();
  98                 $t->mDbkeyform = $key;
  99                 if ( $t->secureAndSplit() ) {
 100                         return $t;
 101                 } else {
 102                         return null;
 103                 }
 104         }
 105
 106         /**
 107          * Create a new Title from text, such as what one would find in a link. De-
 108          * codes any HTML entities in the text.
 109          *
 110          * @param $text string  The link text; spaces, prefixes, and an
 111          *   initial ':' indicating the main namespace are accepted.
 112          * @param $defaultNamespace int The namespace to use if none is speci-
 113          *   fied by a prefix.  If you want to force a specific namespace even if
 114          *   $text might begin with a namespace prefix, use makeTitle() or
 115          *   makeTitleSafe().
 116          * @return Title  The new object, or null on an error.
 117          */
 118         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 119                 if ( is_object( $text ) ) {
 120                         throw new MWException( 'Title::newFromText given an object' );
 121                 }
 122
 123                 /**
 124                  * Wiki pages often contain multiple links to the same page.
 125                  * Title normalization and parsing can become expensive on
 126                  * pages with many links, so we can save a little time by
 127                  * caching them.
 128                  *
 129                  * In theory these are value objects and won't get changed...
 130                  */
 131                 if ( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 132                         return Title::$titleCache[$text];
 133                 }
 134
 135                 /**
 136                  * Convert things like &eacute; &#257; or &#x3017; into normalized (bug 14952) text
 137                  */
 138                 $filteredText = Sanitizer::decodeCharReferencesAndNormalize( $text );
 139
 140                 $t = new Title();
 141                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 142                 $t->mDefaultNamespace = $defaultNamespace;
 143
 144                 static $cachedcount = 0 ;
 145                 if ( $t->secureAndSplit() ) {
 146                         if ( $defaultNamespace == NS_MAIN ) {
 147                                 if ( $cachedcount >= self::CACHE_MAX ) {
 148                                         # Avoid memory leaks on mass operations...
 149                                         Title::$titleCache = array();
 150                                         $cachedcount = 0;
 151                                 }
 152                                 $cachedcount++;
 153                                 Title::$titleCache[$text] =& $t;
 154                         }
 155                         return $t;
 156                 } else {
 157                         $ret = null;
 158                         return $ret;
 159                 }
 160         }
 161
 162         /**
 163          * THIS IS NOT THE FUNCTION YOU WANT. Use Title::newFromText().
 164          *
 165          * Example of wrong and broken code:
 166          * $title = Title::newFromURL( $wgRequest->getVal( 'title' ) );
 167          *
 168          * Example of right code:
 169          * $title = Title::newFromText( $wgRequest->getVal( 'title' ) );
 170          *
 171          * Create a new Title from URL-encoded text. Ensures that
 172          * the given title's length does not exceed the maximum.
 173          *
 174          * @param $url \type{\string} the title, as might be taken from a URL
 175          * @return \type{Title} the new object, or NULL on an error
 176          */
 177         public static function newFromURL( $url ) {
 178                 global $wgLegalTitleChars;
 179                 $t = new Title();
 180
 181                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 182                 # but some URLs used it as a space replacement and they still come
 183                 # from some external search tools.
 184                 if ( strpos( $wgLegalTitleChars, '+' ) === false ) {
 185                         $url = str_replace( '+', ' ', $url );
 186                 }
 187
 188                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 189                 if ( $t->secureAndSplit() ) {
 190                         return $t;
 191                 } else {
 192                         return null;
 193                 }
 194         }
 195
 196         /**
 197          * Create a new Title from an article ID
 198          *
 199          * @param $id \type{\int} the page_id corresponding to the Title to create
 200          * @param $flags \type{\int} use Title::GAID_FOR_UPDATE to use master
 201          * @return \type{Title} the new object, or NULL on an error
 202          */
 203         public static function newFromID( $id, $flags = 0 ) {
 204                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
 205                 $row = $db->selectRow( 'page', '*', array( 'page_id' => $id ), __METHOD__ );
 206                 if ( $row !== false ) {
 207                         $title = Title::newFromRow( $row );
 208                 } else {
 209                         $title = null;
 210                 }
 211                 return $title;
 212         }
 213
 214         /**
 215          * Make an array of titles from an array of IDs
 216          *
 217          * @param $ids \type{\arrayof{\int}} Array of IDs
 218          * @return \type{\arrayof{Title}} Array of Titles
 219          */
 220         public static function newFromIDs( $ids ) {
 221                 if ( !count( $ids ) ) {
 222                         return array();
 223                 }
 224                 $dbr = wfGetDB( DB_SLAVE );
 225
 226                 $res = $dbr->select(
 227                         'page',
 228                         array(
 229                                 'page_namespace', 'page_title', 'page_id',
 230                                 'page_len', 'page_is_redirect', 'page_latest',
 231                         ),
 232                         array( 'page_id' => $ids ),
 233                         __METHOD__
 234                 );
 235
 236                 $titles = array();
 237                 foreach ( $res as $row ) {
 238                         $titles[] = Title::newFromRow( $row );
 239                 }
 240                 return $titles;
 241         }
 242
 243         /**
 244          * Make a Title object from a DB row
 245          *
 246          * @param $row \type{Row} (needs at least page_title,page_namespace)
 247          * @return \type{Title} corresponding Title
 248          */
 249         public static function newFromRow( $row ) {
 250                 $t = self::makeTitle( $row->page_namespace, $row->page_title );
 251
 252                 $t->mArticleID = isset( $row->page_id ) ? intval( $row->page_id ) : -1;
 253                 $t->mLength = isset( $row->page_len ) ? intval( $row->page_len ) : -1;
 254                 $t->mRedirect = isset( $row->page_is_redirect ) ? (bool)$row->page_is_redirect : null;
 255                 $t->mLatestID = isset( $row->page_latest ) ? intval( $row->page_latest ) : false;
 256
 257                 return $t;
 258         }
 259
 260         /**
 261          * Create a new Title from a namespace index and a DB key.
 262          * It's assumed that $ns and $title are *valid*, for instance when
 263          * they came directly from the database or a special page name.
 264          * For convenience, spaces are converted to underscores so that
 265          * eg user_text fields can be used directly.
 266          *
 267          * @param $ns \type{\int} the namespace of the article
 268          * @param $title \type{\string} the unprefixed database key form
 269          * @param $fragment \type{\string} The link fragment (after the "#")
 270          * @param $interwiki \type{\string} The interwiki prefix
 271          * @return \type{Title} the new object
 272          */
 273         public static function &makeTitle( $ns, $title, $fragment = '', $interwiki = '' ) {
 274                 $t = new Title();
 275                 $t->mInterwiki = $interwiki;
 276                 $t->mFragment = $fragment;
 277                 $t->mNamespace = $ns = intval( $ns );
 278                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 279                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 280                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 281                 $t->mTextform = str_replace( '_', ' ', $title );
 282                 return $t;
 283         }
 284
 285         /**
 286          * Create a new Title from a namespace index and a DB key.
 287          * The parameters will be checked for validity, which is a bit slower
 288          * than makeTitle() but safer for user-provided data.
 289          *
 290          * @param $ns \type{\int} the namespace of the article
 291          * @param $title \type{\string} the database key form
 292          * @param $fragment \type{\string} The link fragment (after the "#")
 293          * @param $interwiki \type{\string} The interwiki prefix
 294          * @return \type{Title} the new object, or NULL on an error
 295          */
 296         public static function makeTitleSafe( $ns, $title, $fragment = '', $interwiki = '' ) {
 297                 $t = new Title();
 298                 $t->mDbkeyform = Title::makeName( $ns, $title, $fragment, $interwiki );
 299                 if ( $t->secureAndSplit() ) {
 300                         return $t;
 301                 } else {
 302                         return null;
 303                 }
 304         }
 305
 306         /**
 307          * Create a new Title for the Main Page
 308          *
 309          * @return \type{Title} the new object
 310          */
 311         public static function newMainPage() {
 312                 $title = Title::newFromText( wfMsgForContent( 'mainpage' ) );
 313                 // Don't give fatal errors if the message is broken
 314                 if ( !$title ) {
 315                         $title = Title::newFromText( 'Main Page' );
 316                 }
 317                 return $title;
 318         }
 319
 320         /**
 321          * Extract a redirect destination from a string and return the
 322          * Title, or null if the text doesn't contain a valid redirect
 323          * This will only return the very next target, useful for
 324          * the redirect table and other checks that don't need full recursion
 325          *
 326          * @param $text \type{\string} Text with possible redirect
 327          * @return \type{Title} The corresponding Title
 328          */
 329         public static function newFromRedirect( $text ) {
 330                 return self::newFromRedirectInternal( $text );
 331         }
 332
 333         /**
 334          * Extract a redirect destination from a string and return the
 335          * Title, or null if the text doesn't contain a valid redirect
 336          * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
 337          * in order to provide (hopefully) the Title of the final destination instead of another redirect
 338          *
 339          * @param $text \type{\string} Text with possible redirect
 340          * @return \type{Title} The corresponding Title
 341          */
 342         public static function newFromRedirectRecurse( $text ) {
 343                 $titles = self::newFromRedirectArray( $text );
 344                 return $titles ? array_pop( $titles ) : null;
 345         }
 346
 347         /**
 348          * Extract a redirect destination from a string and return an
 349          * array of Titles, or null if the text doesn't contain a valid redirect
 350          * The last element in the array is the final destination after all redirects
 351          * have been resolved (up to $wgMaxRedirects times)
 352          *
 353          * @param $text \type{\string} Text with possible redirect
 354          * @return \type{\array} Array of Titles, with the destination last
 355          */
 356         public static function newFromRedirectArray( $text ) {
 357                 global $wgMaxRedirects;
 358                 // are redirects disabled?
 359                 if ( $wgMaxRedirects < 1 ) {
 360                         return null;
 361                 }
 362                 $title = self::newFromRedirectInternal( $text );
 363                 if ( is_null( $title ) ) {
 364                         return null;
 365                 }
 366                 // recursive check to follow double redirects
 367                 $recurse = $wgMaxRedirects;
 368                 $titles = array( $title );
 369                 while ( --$recurse > 0 ) {
 370                         if ( $title->isRedirect() ) {
 371                                 $article = new Article( $title, 0 );
 372                                 $newtitle = $article->getRedirectTarget();
 373                         } else {
 374                                 break;
 375                         }
 376                         // Redirects to some special pages are not permitted
 377                         if ( $newtitle instanceOf Title && $newtitle->isValidRedirectTarget() ) {
 378                                 // the new title passes the checks, so make that our current title so that further recursion can be checked
 379                                 $title = $newtitle;
 380                                 $titles[] = $newtitle;
 381                         } else {
 382                                 break;
 383                         }
 384                 }
 385                 return $titles;
 386         }
 387
 388         /**
 389          * Really extract the redirect destination
 390          * Do not call this function directly, use one of the newFromRedirect* functions above
 391          *
 392          * @param $text \type{\string} Text with possible redirect
 393          * @return \type{Title} The corresponding Title
 394          */
 395         protected static function newFromRedirectInternal( $text ) {
 396                 $redir = MagicWord::get( 'redirect' );
 397                 $text = trim( $text );
 398                 if ( $redir->matchStartAndRemove( $text ) ) {
 399                         // Extract the first link and see if it's usable
 400                         // Ensure that it really does come directly after #REDIRECT
 401                         // Some older redirects included a colon, so don't freak about that!
 402                         $m = array();
 403                         if ( preg_match( '!^\s*:?\s*\[{2}(.*?)(?:\|.*?)?\]{2}!', $text, $m ) ) {
 404                                 // Strip preceding colon used to "escape" categories, etc.
 405                                 // and URL-decode links
 406                                 if ( strpos( $m[1], '%' ) !== false ) {
 407                                         // Match behavior of inline link parsing here;
 408                                         // don't interpret + as " " most of the time!
 409                                         // It might be safe to just use rawurldecode instead, though.
 410                                         $m[1] = urldecode( ltrim( $m[1], ':' ) );
 411                                 }
 412                                 $title = Title::newFromText( $m[1] );
 413                                 // If the title is a redirect to bad special pages or is invalid, return null
 414                                 if ( !$title instanceof Title || !$title->isValidRedirectTarget() ) {
 415                                         return null;
 416                                 }
 417                                 return $title;
 418                         }
 419                 }
 420                 return null;
 421         }
 422
 423 # ----------------------------------------------------------------------------
 424 #       Static functions
 425 # ----------------------------------------------------------------------------
 426
 427         /**
 428          * Get the prefixed DB key associated with an ID
 429          *
 430          * @param $id \type{\int} the page_id of the article
 431          * @return \type{Title} an object representing the article, or NULL
 432          *  if no such article was found
 433          */
 434         public static function nameOf( $id ) {
 435                 $dbr = wfGetDB( DB_SLAVE );
 436
 437                 $s = $dbr->selectRow(
 438                         'page',
 439                         array( 'page_namespace', 'page_title' ),
 440                         array( 'page_id' => $id ),
 441                         __METHOD__
 442                 );
 443                 if ( $s === false ) {
 444                         return null;
 445                 }
 446
 447                 $n = self::makeName( $s->page_namespace, $s->page_title );
 448                 return $n;
 449         }
 450
 451         /**
 452          * Get a regex character class describing the legal characters in a link
 453          *
 454          * @return \type{\string} the list of characters, not delimited
 455          */
 456         public static function legalChars() {
 457                 global $wgLegalTitleChars;
 458                 return $wgLegalTitleChars;
 459         }
 460
 461         /**
 462          * Get a string representation of a title suitable for
 463          * including in a search index
 464          *
 465          * @param $ns \type{\int} a namespace index
 466          * @param $title \type{\string} text-form main part
 467          * @return \type{\string} a stripped-down title string ready for the
 468          *  search index
 469          */
 470         public static function indexTitle( $ns, $title ) {
 471                 global $wgContLang;
 472
 473                 $lc = SearchEngine::legalSearchChars() . '&#;';
 474                 $t = $wgContLang->normalizeForSearch( $title );
 475                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 476                 $t = $wgContLang->lc( $t );
 477
 478                 # Handle 's, s'
 479                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 480                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 481
 482                 $t = preg_replace( "/\\s+/", ' ', $t );
 483
 484                 if ( $ns == NS_FILE ) {
 485                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 486                 }
 487                 return trim( $t );
 488         }
 489
 490         /**
 491          * Make a prefixed DB key from a DB key and a namespace index
 492          *
 493          * @param $ns \type{\int} numerical representation of the namespace
 494          * @param $title \type{\string} the DB key form the title
 495          * @param $fragment \type{\string} The link fragment (after the "#")
 496          * @param $interwiki \type{\string} The interwiki prefix
 497          * @return \type{\string} the prefixed form of the title
 498          */
 499         public static function makeName( $ns, $title, $fragment = '', $interwiki = '' ) {
 500                 global $wgContLang;
 501
 502                 $namespace = $wgContLang->getNsText( $ns );
 503                 $name = $namespace == '' ? $title : "$namespace:$title";
 504                 if ( strval( $interwiki ) != '' ) {
 505                         $name = "$interwiki:$name";
 506                 }
 507                 if ( strval( $fragment ) != '' ) {
 508                         $name .= '#' . $fragment;
 509                 }
 510                 return $name;
 511         }
 512
 513         /**
 514          * Determine whether the object refers to a page within
 515          * this project.
 516          *
 517          * @return \type{\bool} TRUE if this is an in-project interwiki link
 518          *      or a wikilink, FALSE otherwise
 519          */
 520         public function isLocal() {
 521                 if ( $this->mInterwiki != '' ) {
 522                         return Interwiki::fetch( $this->mInterwiki )->isLocal();
 523                 } else {
 524                         return true;
 525                 }
 526         }
 527
 528         /**
 529          * Determine whether the object refers to a page within
 530          * this project and is transcludable.
 531          *
 532          * @return \type{\bool} TRUE if this is transcludable
 533          */
 534         public function isTrans() {
 535                 if ( $this->mInterwiki == '' ) {
 536                         return false;
 537                 }
 538
 539                 return Interwiki::fetch( $this->mInterwiki )->isTranscludable();
 540         }
 541
 542         /**
 543          * Returns the DB name of the distant wiki
 544          * which owns the object.
 545          *
 546          * @return \type{\string} the DB name
 547          */
 548         public function getTransWikiID() {
 549                 if ( $this->mInterwiki == '' ) {
 550                         return false;
 551                 }
 552
 553                 return Interwiki::fetch( $this->mInterwiki )->getWikiID();
 554         }
 555
 556         /**
 557          * Escape a text fragment, say from a link, for a URL
 558          *
 559          * @param $fragment string containing a URL or link fragment (after the "#")
 560          * @return String: escaped string
 561          */
 562         static function escapeFragmentForURL( $fragment ) {
 563                 # Note that we don't urlencode the fragment.  urlencoded Unicode
 564                 # fragments appear not to work in IE (at least up to 7) or in at least
 565                 # one version of Opera 9.x.  The W3C validator, for one, doesn't seem
 566                 # to care if they aren't encoded.
 567                 return Sanitizer::escapeId( $fragment, 'noninitial' );
 568         }
 569
 570 # ----------------------------------------------------------------------------
 571 #       Other stuff
 572 # ----------------------------------------------------------------------------
 573
 574         /** Simple accessors */
 575         /**
 576          * Get the text form (spaces not underscores) of the main part
 577          *
 578          * @return \type{\string} Main part of the title
 579          */
 580         public function getText() { return $this->mTextform; }
 581
 582         /**
 583          * Get the URL-encoded form of the main part
 584          *
 585          * @return \type{\string} Main part of the title, URL-encoded
 586          */
 587         public function getPartialURL() { return $this->mUrlform; }
 588
 589         /**
 590          * Get the main part with underscores
 591          *
 592          * @return \type{\string} Main part of the title, with underscores
 593          */
 594         public function getDBkey() { return $this->mDbkeyform; }
 595
 596         /**
 597          * Get the namespace index, i.e.\ one of the NS_xxxx constants.
 598          *
 599          * @return \type{\int} Namespace index
 600          */
 601         public function getNamespace() { return $this->mNamespace; }
 602
 603         /**
 604          * Get the namespace text
 605          *
 606          * @return \type{\string} Namespace text
 607          */
 608         public function getNsText() {
 609                 global $wgContLang;
 610
 611                 if ( $this->mInterwiki != '' ) {
 612                         // This probably shouldn't even happen. ohh man, oh yuck.
 613                         // But for interwiki transclusion it sometimes does.
 614                         // Shit. Shit shit shit.
 615                         //
 616                         // Use the canonical namespaces if possible to try to
 617                         // resolve a foreign namespace.
 618                         if ( MWNamespace::exists( $this->mNamespace ) ) {
 619                                 return MWNamespace::getCanonicalName( $this->mNamespace );
 620                         }
 621                 }
 622                 return $wgContLang->getNsText( $this->mNamespace );
 623         }
 624
 625         /**
 626          * Get the DB key with the initial letter case as specified by the user
 627          *
 628          * @return \type{\string} DB key
 629          */
 630         function getUserCaseDBKey() {
 631                 return $this->mUserCaseDBKey;
 632         }
 633
 634         /**
 635          * Get the namespace text of the subject (rather than talk) page
 636          *
 637          * @return \type{\string} Namespace text
 638          */
 639         public function getSubjectNsText() {
 640                 global $wgContLang;
 641                 return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
 642         }
 643
 644         /**
 645          * Get the namespace text of the talk page
 646          *
 647          * @return \type{\string} Namespace text
 648          */
 649         public function getTalkNsText() {
 650                 global $wgContLang;
 651                 return( $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) ) );
 652         }
 653
 654         /**
 655          * Could this title have a corresponding talk page?
 656          *
 657          * @return \type{\bool} TRUE or FALSE
 658          */
 659         public function canTalk() {
 660                 return( MWNamespace::canTalk( $this->mNamespace ) );
 661         }
 662
 663         /**
 664          * Get the interwiki prefix (or null string)
 665          *
 666          * @return \type{\string} Interwiki prefix
 667          */
 668         public function getInterwiki() { return $this->mInterwiki; }
 669
 670         /**
 671          * Get the Title fragment (i.e.\ the bit after the #) in text form
 672          *
 673          * @return \type{\string} Title fragment
 674          */
 675         public function getFragment() { return $this->mFragment; }
 676
 677         /**
 678          * Get the fragment in URL form, including the "#" character if there is one
 679          * @return \type{\string} Fragment in URL form
 680          */
 681         public function getFragmentForURL() {
 682                 if ( $this->mFragment == '' ) {
 683                         return '';
 684                 } else {
 685                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
 686                 }
 687         }
 688
 689         /**
 690          * Get the default namespace index, for when there is no namespace
 691          *
 692          * @return \type{\int} Default namespace index
 693          */
 694         public function getDefaultNamespace() { return $this->mDefaultNamespace; }
 695
 696         /**
 697          * Get title for search index
 698          *
 699          * @return \type{\string} a stripped-down title string ready for the
 700          *  search index
 701          */
 702         public function getIndexTitle() {
 703                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 704         }
 705
 706         /**
 707          * Get the prefixed database key form
 708          *
 709          * @return \type{\string} the prefixed title, with underscores and
 710          *  any interwiki and namespace prefixes
 711          */
 712         public function getPrefixedDBkey() {
 713                 $s = $this->prefix( $this->mDbkeyform );
 714                 $s = str_replace( ' ', '_', $s );
 715                 return $s;
 716         }
 717
 718         /**
 719          * Get the prefixed title with spaces.
 720          * This is the form usually used for display
 721          *
 722          * @return \type{\string} the prefixed title, with spaces
 723          */
 724         public function getPrefixedText() {
 725                 if ( empty( $this->mPrefixedText ) ) { // FIXME: bad usage of empty() ?
 726                         $s = $this->prefix( $this->mTextform );
 727                         $s = str_replace( '_', ' ', $s );
 728                         $this->mPrefixedText = $s;
 729                 }
 730                 return $this->mPrefixedText;
 731         }
 732
 733         /**
 734          * Get the prefixed title with spaces, plus any fragment
 735          * (part beginning with '#')
 736          *
 737          * @return \type{\string} the prefixed title, with spaces and
 738          *  the fragment, including '#'
 739          */
 740         public function getFullText() {
 741                 $text = $this->getPrefixedText();
 742                 if ( $this->mFragment != '' ) {
 743                         $text .= '#' . $this->mFragment;
 744                 }
 745                 return $text;
 746         }
 747
 748         /**
 749          * Get the base name, i.e. the leftmost parts before the /
 750          *
 751          * @return \type{\string} Base name
 752          */
 753         public function getBaseText() {
 754                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
 755                         return $this->getText();
 756                 }
 757
 758                 $parts = explode( '/', $this->getText() );
 759                 # Don't discard the real title if there's no subpage involved
 760                 if ( count( $parts ) > 1 ) {
 761                         unset( $parts[count( $parts ) - 1] );
 762                 }
 763                 return implode( '/', $parts );
 764         }
 765
 766         /**
 767          * Get the lowest-level subpage name, i.e. the rightmost part after /
 768          *
 769          * @return \type{\string} Subpage name
 770          */
 771         public function getSubpageText() {
 772                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
 773                         return( $this->mTextform );
 774                 }
 775                 $parts = explode( '/', $this->mTextform );
 776                 return( $parts[count( $parts ) - 1] );
 777         }
 778
 779         /**
 780          * Get a URL-encoded form of the subpage text
 781          *
 782          * @return \type{\string} URL-encoded subpage name
 783          */
 784         public function getSubpageUrlForm() {
 785                 $text = $this->getSubpageText();
 786                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
 787                 return( $text );
 788         }
 789
 790         /**
 791          * Get a URL-encoded title (not an actual URL) including interwiki
 792          *
 793          * @return \type{\string} the URL-encoded form
 794          */
 795         public function getPrefixedURL() {
 796                 $s = $this->prefix( $this->mDbkeyform );
 797                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
 798                 return $s;
 799         }
 800
 801         /**
 802          * Get a real URL referring to this title, with interwiki link and
 803          * fragment
 804          *
 805          * @param $query \twotypes{\string,\array} an optional query string, not used for interwiki
 806          *   links. Can be specified as an associative array as well, e.g.,
 807          *   array( 'action' => 'edit' ) (keys and values will be URL-escaped).
 808          * @param $variant \type{\string} language variant of url (for sr, zh..)
 809          * @return \type{\string} the URL
 810          */
 811         public function getFullURL( $query = '', $variant = false ) {
 812                 global $wgServer, $wgRequest;
 813
 814                 if ( is_array( $query ) ) {
 815                         $query = wfArrayToCGI( $query );
 816                 }
 817
 818                 $interwiki = Interwiki::fetch( $this->mInterwiki );
 819                 if ( !$interwiki ) {
 820                         $url = $this->getLocalURL( $query, $variant );
 821
 822                         // Ugly quick hack to avoid duplicate prefixes (bug 4571 etc)
 823                         // Correct fix would be to move the prepending elsewhere.
 824                         if ( $wgRequest->getVal( 'action' ) != 'render' ) {
 825                                 $url = $wgServer . $url;
 826                         }
 827                 } else {
 828                         $baseUrl = $interwiki->getURL();
 829
 830                         $namespace = wfUrlencode( $this->getNsText() );
 831                         if ( $namespace != '' ) {
 832                                 # Can this actually happen? Interwikis shouldn't be parsed.
 833                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
 834                                 $namespace .= ':';
 835                         }
 836                         $url = str_replace( '$1', $namespace . $this->mUrlform, $baseUrl );
 837                         $url = wfAppendQuery( $url, $query );
 838                 }
 839
 840                 # Finally, add the fragment.
 841                 $url .= $this->getFragmentForURL();
 842
 843                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
 844                 return $url;
 845         }
 846
 847         /**
 848          * Get a URL with no fragment or server name.  If this page is generated
 849          * with action=render, $wgServer is prepended.
 850          *
 851          * @param $query Mixed: an optional query string; if not specified,
 852          *   $wgArticlePath will be used.  Can be specified as an associative array
 853          *   as well, e.g., array( 'action' => 'edit' ) (keys and values will be
 854          *   URL-escaped).
 855          * @param $variant \type{\string} language variant of url (for sr, zh..)
 856          * @return \type{\string} the URL
 857          */
 858         public function getLocalURL( $query = '', $variant = false ) {
 859                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
 860                 global $wgVariantArticlePath, $wgContLang, $wgUser;
 861
 862                 if ( is_array( $query ) ) {
 863                         $query = wfArrayToCGI( $query );
 864                 }
 865
 866                 // internal links should point to same variant as current page (only anonymous users)
 867                 if ( !$variant && $wgContLang->hasVariants() && !$wgUser->isLoggedIn() ) {
 868                         $pref = $wgContLang->getPreferredVariant( false );
 869                         if ( $pref != $wgContLang->getCode() ) {
 870                                 $variant = $pref;
 871                         }
 872                 }
 873
 874                 if ( $this->isExternal() ) {
 875                         $url = $this->getFullURL();
 876                         if ( $query ) {
 877                                 // This is currently only used for edit section links in the
 878                                 // context of interwiki transclusion. In theory we should
 879                                 // append the query to the end of any existing query string,
 880                                 // but interwiki transclusion is already broken in that case.
 881                                 $url .= "?$query";
 882                         }
 883                 } else {
 884                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 885                         if ( $query == '' ) {
 886                                 if ( $variant != false && $wgContLang->hasVariants() ) {
 887                                         if ( !$wgVariantArticlePath ) {
 888                                                 $variantArticlePath =  "$wgScript?title=$1&variant=$2"; // default
 889                                         } else {
 890                                                 $variantArticlePath = $wgVariantArticlePath;
 891                                         }
 892                                         $url = str_replace( '$2', urlencode( $variant ), $variantArticlePath );
 893                                         $url = str_replace( '$1', $dbkey, $url  );
 894                                 } else {
 895                                         $url = str_replace( '$1', $dbkey, $wgArticlePath );
 896                                 }
 897                         } else {
 898                                 global $wgActionPaths;
 899                                 $url = false;
 900                                 $matches = array();
 901                                 if ( !empty( $wgActionPaths ) &&
 902                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
 903                                 {
 904                                         $action = urldecode( $matches[2] );
 905                                         if ( isset( $wgActionPaths[$action] ) ) {
 906                                                 $query = $matches[1];
 907                                                 if ( isset( $matches[4] ) ) {
 908                                                         $query .= $matches[4];
 909                                                 }
 910                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
 911                                                 if ( $query != '' ) {
 912                                                         $url = wfAppendQuery( $url, $query );
 913                                                 }
 914                                         }
 915                                 }
 916                                 if ( $url === false ) {
 917                                         if ( $query == '-' ) {
 918                                                 $query = '';
 919                                         }
 920                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
 921                                 }
 922                         }
 923
 924                         // FIXME: this causes breakage in various places when we
 925                         // actually expected a local URL and end up with dupe prefixes.
 926                         if ( $wgRequest->getVal( 'action' ) == 'render' ) {
 927                                 $url = $wgServer . $url;
 928                         }
 929                 }
 930                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
 931                 return $url;
 932         }
 933
 934         /**
 935          * Get a URL that's the simplest URL that will be valid to link, locally,
 936          * to the current Title.  It includes the fragment, but does not include
 937          * the server unless action=render is used (or the link is external).  If
 938          * there's a fragment but the prefixed text is empty, we just return a link
 939          * to the fragment.
 940          *
 941          * The result obviously should not be URL-escaped, but does need to be
 942          * HTML-escaped if it's being output in HTML.
 943          *
 944          * @param $query \type{\arrayof{\string}} An associative array of key => value pairs for the
 945          *   query string.  Keys and values will be escaped.
 946          * @param $variant \type{\string} Language variant of URL (for sr, zh..).  Ignored
 947          *   for external links.  Default is "false" (same variant as current page,
 948          *   for anonymous users).
 949          * @return \type{\string} the URL
 950          */
 951         public function getLinkUrl( $query = array(), $variant = false ) {
 952                 wfProfileIn( __METHOD__ );
 953                 if ( $this->isExternal() ) {
 954                         $ret = $this->getFullURL( $query );
 955                 } elseif ( $this->getPrefixedText() === '' && $this->getFragment() !== '' ) {
 956                         $ret = $this->getFragmentForURL();
 957                 } else {
 958                         $ret = $this->getLocalURL( $query, $variant ) . $this->getFragmentForURL();
 959                 }
 960                 wfProfileOut( __METHOD__ );
 961                 return $ret;
 962         }
 963
 964         /**
 965          * Get an HTML-escaped version of the URL form, suitable for
 966          * using in a link, without a server name or fragment
 967          *
 968          * @param $query \type{\string} an optional query string
 969          * @return \type{\string} the URL
 970          */
 971         public function escapeLocalURL( $query = '' ) {
 972                 return htmlspecialchars( $this->getLocalURL( $query ) );
 973         }
 974
 975         /**
 976          * Get an HTML-escaped version of the URL form, suitable for
 977          * using in a link, including the server name and fragment
 978          *
 979          * @param $query \type{\string} an optional query string
 980          * @return \type{\string} the URL
 981          */
 982         public function escapeFullURL( $query = '' ) {
 983                 return htmlspecialchars( $this->getFullURL( $query ) );
 984         }
 985
 986         /**
 987          * Get the URL form for an internal link.
 988          * - Used in various Squid-related code, in case we have a different
 989          * internal hostname for the server from the exposed one.
 990          *
 991          * @param $query \type{\string} an optional query string
 992          * @param $variant \type{\string} language variant of url (for sr, zh..)
 993          * @return \type{\string} the URL
 994          */
 995         public function getInternalURL( $query = '', $variant = false ) {
 996                 global $wgInternalServer;
 997                 $url = $wgInternalServer . $this->getLocalURL( $query, $variant );
 998                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
 999                 return $url;
1000         }
1001
1002         /**
1003          * Get the edit URL for this Title
1004          *
1005          * @return \type{\string} the URL, or a null string if this is an
1006          *  interwiki link
1007          */
1008         public function getEditURL() {
1009                 if ( $this->mInterwiki != '' ) {
1010                         return '';
1011                 }
1012                 $s = $this->getLocalURL( 'action=edit' );
1013
1014                 return $s;
1015         }
1016
1017         /**
1018          * Get the HTML-escaped displayable text form.
1019          * Used for the title field in <a> tags.
1020          *
1021          * @return \type{\string} the text, including any prefixes
1022          */
1023         public function getEscapedText() {
1024                 return htmlspecialchars( $this->getPrefixedText() );
1025         }
1026
1027         /**
1028          * Is this Title interwiki?
1029          *
1030          * @return \type{\bool}
1031          */
1032         public function isExternal() {
1033                 return ( $this->mInterwiki != '' );
1034         }
1035
1036         /**
1037          * Is this page "semi-protected" - the *only* protection is autoconfirm?
1038          *
1039          * @param $action \type{\string} Action to check (default: edit)
1040          * @return \type{\bool}
1041          */
1042         public function isSemiProtected( $action = 'edit' ) {
1043                 if ( $this->exists() ) {
1044                         $restrictions = $this->getRestrictions( $action );
1045                         if ( count( $restrictions ) > 0 ) {
1046                                 foreach ( $restrictions as $restriction ) {
1047                                         if ( strtolower( $restriction ) != 'autoconfirmed' ) {
1048                                                 return false;
1049                                         }
1050                                 }
1051                         } else {
1052                                 # Not protected
1053                                 return false;
1054                         }
1055                         return true;
1056                 } else {
1057                         # If it doesn't exist, it can't be protected
1058                         return false;
1059                 }
1060         }
1061
1062         /**
1063          * Does the title correspond to a protected article?
1064          *
1065          * @param $action \type{\string} the action the page is protected from,
1066          * by default checks all actions.
1067          * @return \type{\bool}
1068          */
1069         public function isProtected( $action = '' ) {
1070                 global $wgRestrictionLevels;
1071
1072                 $restrictionTypes = $this->getRestrictionTypes();
1073
1074                 # Special pages have inherent protection
1075                 if( $this->getNamespace() == NS_SPECIAL ) {
1076                         return true;
1077                 }
1078
1079                 # Check regular protection levels
1080                 foreach ( $restrictionTypes as $type ) {
1081                         if ( $action == $type || $action == '' ) {
1082                                 $r = $this->getRestrictions( $type );
1083                                 foreach ( $wgRestrictionLevels as $level ) {
1084                                         if ( in_array( $level, $r ) && $level != '' ) {
1085                                                 return true;
1086                                         }
1087                                 }
1088                         }
1089                 }
1090
1091                 return false;
1092         }
1093
1094         /**
1095          * Is this a conversion table for the LanguageConverter?
1096          *
1097          * @return \type{\bool}
1098          */
1099         public function isConversionTable() {
1100                 if(
1101                         $this->getNamespace() == NS_MEDIAWIKI &&
1102                         strpos( $this->getText(), 'Conversiontable' ) !== false
1103                 )
1104                 {
1105                         return true;
1106                 }
1107
1108                 return false;
1109         }
1110
1111         /**
1112          * Is $wgUser watching this page?
1113          *
1114          * @return \type{\bool}
1115          */
1116         public function userIsWatching() {
1117                 global $wgUser;
1118
1119                 if ( is_null( $this->mWatched ) ) {
1120                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn() ) {
1121                                 $this->mWatched = false;
1122                         } else {
1123                                 $this->mWatched = $wgUser->isWatched( $this );
1124                         }
1125                 }
1126                 return $this->mWatched;
1127         }
1128
1129         /**
1130          * Can $wgUser perform $action on this page?
1131          * This skips potentially expensive cascading permission checks
1132          * as well as avoids expensive error formatting
1133          *
1134          * Suitable for use for nonessential UI controls in common cases, but
1135          * _not_ for functional access control.
1136          *
1137          * May provide false positives, but should never provide a false negative.
1138          *
1139          * @param $action \type{\string} action that permission needs to be checked for
1140          * @return \type{\bool}
1141          */
1142         public function quickUserCan( $action ) {
1143                 return $this->userCan( $action, false );
1144         }
1145
1146         /**
1147          * Determines if $wgUser is unable to edit this page because it has been protected
1148          * by $wgNamespaceProtection.
1149          *
1150          * @return \type{\bool}
1151          */
1152         public function isNamespaceProtected() {
1153                 global $wgNamespaceProtection, $wgUser;
1154                 if ( isset( $wgNamespaceProtection[$this->mNamespace] ) ) {
1155                         foreach ( (array)$wgNamespaceProtection[$this->mNamespace] as $right ) {
1156                                 if ( $right != '' && !$wgUser->isAllowed( $right ) ) {
1157                                         return true;
1158                                 }
1159                         }
1160                 }
1161                 return false;
1162         }
1163
1164         /**
1165          * Can $wgUser perform $action on this page?
1166          *
1167          * @param $action \type{\string} action that permission needs to be checked for
1168          * @param $doExpensiveQueries \type{\bool} Set this to false to avoid doing unnecessary queries.
1169          * @return \type{\bool}
1170          */
1171         public function userCan( $action, $doExpensiveQueries = true ) {
1172                 global $wgUser;
1173                 return ( $this->getUserPermissionsErrorsInternal( $action, $wgUser, $doExpensiveQueries, true ) === array() );
1174         }
1175
1176         /**
1177          * Can $user perform $action on this page?
1178          *
1179          * FIXME: This *does not* check throttles (User::pingLimiter()).
1180          *
1181          * @param $action \type{\string}action that permission needs to be checked for
1182          * @param $user \type{User} user to check
1183          * @param $doExpensiveQueries \type{\bool} Set this to false to avoid doing unnecessary queries.
1184          * @param $ignoreErrors \type{\arrayof{\string}} Set this to a list of message keys whose corresponding errors may be ignored.
1185          * @return \type{\array} Array of arrays of the arguments to wfMsg to explain permissions problems.
1186          */
1187         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1188                 if ( !StubObject::isRealObject( $user ) ) {
1189                         // Since StubObject is always used on globals, we can
1190                         // unstub $wgUser here and set $user = $wgUser
1191                         global $wgUser;
1192                         $wgUser->_unstub( '', 5 );
1193                         $user = $wgUser;
1194                 }
1195
1196                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1197
1198                 // Remove the errors being ignored.
1199                 foreach ( $errors as $index => $error ) {
1200                         $error_key = is_array( $error ) ? $error[0] : $error;
1201
1202                         if ( in_array( $error_key, $ignoreErrors ) ) {
1203                                 unset( $errors[$index] );
1204                         }
1205                 }
1206
1207                 return $errors;
1208         }
1209
1210         /**
1211          * Permissions checks that fail most often, and which are easiest to test.
1212          *
1213          * @param $action String the action to check
1214          * @param $user User user to check
1215          * @param $errors Array list of current errors
1216          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1217          * @param $short Boolean short circuit on first error
1218          *
1219          * @return Array list of errors
1220          */
1221         private function checkQuickPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1222                 if ( $action == 'create' ) {
1223                         if ( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1224                                  ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1225                                 $errors[] = $user->isAnon() ? array( 'nocreatetext' ) : array( 'nocreate-loggedin' );
1226                         }
1227                 } elseif ( $action == 'move' ) {
1228                         if ( !$user->isAllowed( 'move-rootuserpages' )
1229                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1230                                 // Show user page-specific message only if the user can move other pages
1231                                 $errors[] = array( 'cant-move-user-page' );
1232                         }
1233
1234                         // Check if user is allowed to move files if it's a file
1235                         if ( $this->mNamespace == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1236                                 $errors[] = array( 'movenotallowedfile' );
1237                         }
1238
1239                         if ( !$user->isAllowed( 'move' ) ) {
1240                                 // User can't move anything
1241                                 global $wgGroupPermissions;
1242                                 $userCanMove = false;
1243                                 if ( isset( $wgGroupPermissions['user']['move'] ) ) {
1244                                         $userCanMove = $wgGroupPermissions['user']['move'];
1245                                 }
1246                                 $autoconfirmedCanMove = false;
1247                                 if ( isset( $wgGroupPermissions['autoconfirmed']['move'] ) ) {
1248                                         $autoconfirmedCanMove = $wgGroupPermissions['autoconfirmed']['move'];
1249                                 }
1250                                 if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
1251                                         // custom message if logged-in users without any special rights can move
1252                                         $errors[] = array( 'movenologintext' );
1253                                 } else {
1254                                         $errors[] = array( 'movenotallowed' );
1255                                 }
1256                         }
1257                 } elseif ( $action == 'move-target' ) {
1258                         if ( !$user->isAllowed( 'move' ) ) {
1259                                 // User can't move anything
1260                                 $errors[] = array( 'movenotallowed' );
1261                         } elseif ( !$user->isAllowed( 'move-rootuserpages' )
1262                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1263                                 // Show user page-specific message only if the user can move other pages
1264                                 $errors[] = array( 'cant-move-to-user-page' );
1265                         }
1266                 } elseif ( !$user->isAllowed( $action ) ) {
1267                         $return = null;
1268
1269                         // We avoid expensive display logic for quickUserCan's and such
1270                         $groups = false;
1271                         if ( !$short ) {
1272                                 $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
1273                                         User::getGroupsWithPermission( $action ) );
1274                         }
1275
1276                         if ( $groups ) {
1277                                 global $wgLang;
1278                                 $return = array(
1279                                         'badaccess-groups',
1280                                         $wgLang->commaList( $groups ),
1281                                         count( $groups )
1282                                 );
1283                         } else {
1284                                 $return = array( 'badaccess-group0' );
1285                         }
1286                         $errors[] = $return;
1287                 }
1288
1289                 return $errors;
1290         }
1291
1292         /**
1293          * Add the resulting error code to the errors array
1294          *
1295          * @param $errors Array list of current errors
1296          * @param $result Mixed result of errors
1297          *
1298          * @return Array list of errors
1299          */
1300         private function resultToError( $errors, $result ) {
1301                 if ( is_array( $result ) && count( $result ) && !is_array( $result[0] ) ) {
1302                         // A single array representing an error
1303                         $errors[] = $result;
1304                 } else if ( is_array( $result ) && is_array( $result[0] ) ) {
1305                         // A nested array representing multiple errors
1306                         $errors = array_merge( $errors, $result );
1307                 } else if ( $result !== '' && is_string( $result ) ) {
1308                         // A string representing a message-id
1309                         $errors[] = array( $result );
1310                 } else if ( $result === false ) {
1311                         // a generic "We don't want them to do that"
1312                         $errors[] = array( 'badaccess-group0' );
1313                 }
1314                 return $errors;
1315         }
1316
1317         /**
1318          * Check various permission hooks
1319          * @see checkQuickPermissions for parameter information
1320          */
1321         private function checkPermissionHooks( $action, $user, $errors, $doExpensiveQueries, $short ) {
1322                 // Use getUserPermissionsErrors instead
1323                 $result = '';
1324                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1325                         return $result ? array() : array( array( 'badaccess-group0' ) );
1326                 }
1327                 // Check getUserPermissionsErrors hook
1328                 if ( !wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1329                         $errors = $this->resultToError( $errors, $result );
1330                 }
1331                 // Check getUserPermissionsErrorsExpensive hook
1332                 if ( $doExpensiveQueries && !( $short && count( $errors ) > 0 ) &&
1333                          !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) ) ) {
1334                         $errors = $this->resultToError( $errors, $result );
1335                 }
1336
1337                 return $errors;
1338         }
1339
1340         /**
1341          * Check permissions on special pages & namespaces
1342          * @see checkQuickPermissions for parameter information
1343          */
1344         private function checkSpecialsAndNSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1345                 # Only 'createaccount' and 'execute' can be performed on
1346                 # special pages, which don't actually exist in the DB.
1347                 $specialOKActions = array( 'createaccount', 'execute' );
1348                 if ( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions ) ) {
1349                         $errors[] = array( 'ns-specialprotected' );
1350                 }
1351
1352                 # Check $wgNamespaceProtection for restricted namespaces
1353                 if ( $this->isNamespaceProtected() ) {
1354                         $ns = $this->mNamespace == NS_MAIN ?
1355                                 wfMsg( 'nstab-main' ) : $this->getNsText();
1356                         $errors[] = $this->mNamespace == NS_MEDIAWIKI ?
1357                                 array( 'protectedinterface' ) : array( 'namespaceprotected',  $ns );
1358                 }
1359
1360                 return $errors;
1361         }
1362
1363         /**
1364          * Check CSS/JS sub-page permissions
1365          * @see checkQuickPermissions for parameter information
1366          */
1367         private function checkCSSandJSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1368                 # Protect css/js subpages of user pages
1369                 # XXX: this might be better using restrictions
1370                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssSubpage()
1371                 #      and $this->userCanEditJsSubpage() from working
1372                 # XXX: right 'editusercssjs' is deprecated, for backward compatibility only
1373                 if ( $action != 'patrol' && !$user->isAllowed( 'editusercssjs' )
1374                                 && !preg_match( '/^' . preg_quote( $user->getName(), '/' ) . '\//', $this->mTextform ) ) {
1375                         if ( $this->isCssSubpage() && !$user->isAllowed( 'editusercss' ) ) {
1376                                 $errors[] = array( 'customcssjsprotected' );
1377                         } else if ( $this->isJsSubpage() && !$user->isAllowed( 'edituserjs' ) ) {
1378                                 $errors[] = array( 'customcssjsprotected' );
1379                         }
1380                 }
1381
1382                 return $errors;
1383         }
1384
1385         /**
1386          * Check against page_restrictions table requirements on this
1387          * page. The user must possess all required rights for this
1388          * action.
1389          * @see checkQuickPermissions for parameter information
1390          */
1391         private function checkPageRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1392                 foreach ( $this->getRestrictions( $action ) as $right ) {
1393                         // Backwards compatibility, rewrite sysop -> protect
1394                         if ( $right == 'sysop' ) {
1395                                 $right = 'protect';
1396                         }
1397                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1398                                 // Users with 'editprotected' permission can edit protected pages
1399                                 if ( $action == 'edit' && $user->isAllowed( 'editprotected' ) ) {
1400                                         // Users with 'editprotected' permission cannot edit protected pages
1401                                         // with cascading option turned on.
1402                                         if ( $this->mCascadeRestriction ) {
1403                                                 $errors[] = array( 'protectedpagetext', $right );
1404                                         }
1405                                 } else {
1406                                         $errors[] = array( 'protectedpagetext', $right );
1407                                 }
1408                         }
1409                 }
1410
1411                 return $errors;
1412         }
1413
1414         /**
1415          * Check restrictions on cascading pages.
1416          * @see checkQuickPermissions for parameter information
1417          */
1418         private function checkCascadingSourcesRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1419                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1420                         # We /could/ use the protection level on the source page, but it's
1421                         # fairly ugly as we have to establish a precedence hierarchy for pages
1422                         # included by multiple cascade-protected pages. So just restrict
1423                         # it to people with 'protect' permission, as they could remove the
1424                         # protection anyway.
1425                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1426                         # Cascading protection depends on more than this page...
1427                         # Several cascading protected pages may include this page...
1428                         # Check each cascading level
1429                         # This is only for protection restrictions, not for all actions
1430                         if ( isset( $restrictions[$action] ) ) {
1431                                 foreach ( $restrictions[$action] as $right ) {
1432                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1433                                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1434                                                 $pages = '';
1435                                                 foreach ( $cascadingSources as $page )
1436                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1437                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1438                                         }
1439                                 }
1440                         }
1441                 }
1442
1443                 return $errors;
1444         }
1445
1446         /**
1447          * Check action permissions not already checked in checkQuickPermissions
1448          * @see checkQuickPermissions for parameter information
1449          */
1450         private function checkActionPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1451                 if ( $action == 'protect' ) {
1452                         if ( $this->getUserPermissionsErrors( 'edit', $user ) != array() ) {
1453                                 // If they can't edit, they shouldn't protect.
1454                                 $errors[] = array( 'protect-cantedit' );
1455                         }
1456                 } elseif ( $action == 'create' ) {
1457                         $title_protection = $this->getTitleProtection();
1458                         if( $title_protection ) {
1459                                 if( $title_protection['pt_create_perm'] == 'sysop' ) {
1460                                         $title_protection['pt_create_perm'] = 'protect'; // B/C
1461                                 }
1462                                 if( $title_protection['pt_create_perm'] == '' || !$user->isAllowed( $title_protection['pt_create_perm'] ) ) {
1463                                         $errors[] = array( 'titleprotected', User::whoIs( $title_protection['pt_user'] ), $title_protection['pt_reason'] );
1464                                 }
1465                         }
1466                 } elseif ( $action == 'move' ) {
1467                         // Check for immobile pages
1468                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1469                                 // Specific message for this case
1470                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1471                         } elseif ( !$this->isMovable() ) {
1472                                 // Less specific message for rarer cases
1473                                 $errors[] = array( 'immobile-page' );
1474                         }
1475                 } elseif ( $action == 'move-target' ) {
1476                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1477                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1478                         } elseif ( !$this->isMovable() ) {
1479                                 $errors[] = array( 'immobile-target-page' );
1480                         }
1481                 }
1482                 return $errors;
1483         }
1484
1485         /**
1486          * Check that the user isn't blocked from editting.
1487          * @see checkQuickPermissions for parameter information
1488          */
1489         private function checkUserBlock( $action, $user, $errors, $doExpensiveQueries, $short ) {
1490                 if( $short ) {
1491                         return $errors;
1492                 }
1493
1494                 global $wgContLang, $wgLang, $wgEmailConfirmToEdit;
1495
1496                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() && $action != 'createaccount' ) {
1497                         $errors[] = array( 'confirmedittext' );
1498                 }
1499
1500                 // Edit blocks should not affect reading. Account creation blocks handled at userlogin.
1501                 if ( $action != 'read' && $action != 'createaccount' && $user->isBlockedFrom( $this ) ) {
1502                         $block = $user->mBlock;
1503
1504                         // This is from OutputPage::blockedPage
1505                         // Copied at r23888 by werdna
1506
1507                         $id = $user->blockedBy();
1508                         $reason = $user->blockedFor();
1509                         if ( $reason == '' ) {
1510                                 $reason = wfMsg( 'blockednoreason' );
1511                         }
1512                         $ip = wfGetIP();
1513
1514                         if ( is_numeric( $id ) ) {
1515                                 $name = User::whoIs( $id );
1516                         } else {
1517                                 $name = $id;
1518                         }
1519
1520                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1521                         $blockid = $block->mId;
1522                         $blockExpiry = $user->mBlock->mExpiry;
1523                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $user->mBlock->mTimestamp ), true );
1524                         if ( $blockExpiry == 'infinity' ) {
1525                                 // Entry in database (table ipblocks) is 'infinity' but 'ipboptions' uses 'infinite' or 'indefinite'
1526                                 $scBlockExpiryOptions = wfMsg( 'ipboptions' );
1527
1528                                 foreach ( explode( ',', $scBlockExpiryOptions ) as $option ) {
1529                                         if ( !strpos( $option, ':' ) )
1530                                                 continue;
1531
1532                                         list( $show, $value ) = explode( ':', $option );
1533
1534                                         if ( $value == 'infinite' || $value == 'indefinite' ) {
1535                                                 $blockExpiry = $show;
1536                                                 break;
1537                                         }
1538                                 }
1539                         } else {
1540                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1541                         }
1542
1543                         $intended = $user->mBlock->mAddress;
1544
1545                         $errors[] = array( ( $block->mAuto ? 'autoblockedtext' : 'blockedtext' ), $link, $reason, $ip, $name,
1546                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
1547                 }
1548
1549                 return $errors;
1550         }
1551
1552         /**
1553          * Can $user perform $action on this page? This is an internal function,
1554          * which checks ONLY that previously checked by userCan (i.e. it leaves out
1555          * checks on wfReadOnly() and blocks)
1556          *
1557          * @param $action \type{\string} action that permission needs to be checked for
1558          * @param $user \type{User} user to check
1559          * @param $doExpensiveQueries \type{\bool} Set this to false to avoid doing unnecessary queries.
1560          * @param $short \type{\bool} Set this to true to stop after the first permission error.
1561          * @return \type{\array} Array of arrays of the arguments to wfMsg to explain permissions problems.
1562          */
1563         protected function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true, $short = false ) {
1564                 wfProfileIn( __METHOD__ );
1565
1566                 $errors = array();
1567                 $checks = array(
1568                         'checkQuickPermissions',
1569                         'checkPermissionHooks',
1570                         'checkSpecialsAndNSPermissions',
1571                         'checkCSSandJSPermissions',
1572                         'checkPageRestrictions',
1573                         'checkCascadingSourcesRestrictions',
1574                         'checkActionPermissions',
1575                         'checkUserBlock'
1576                 );
1577
1578                 while( count( $checks ) > 0 &&
1579                            !( $short && count( $errors ) > 0 ) ) {
1580                         $method = array_shift( $checks );
1581                         $errors = $this->$method( $action, $user, $errors, $doExpensiveQueries, $short );
1582                 }
1583
1584                 wfProfileOut( __METHOD__ );
1585                 return $errors;
1586         }
1587
1588         /**
1589          * Is this title subject to title protection?
1590          *
1591          * @return \type{\mixed} An associative array representing any existent title
1592          *   protection, or false if there's none.
1593          */
1594         private function getTitleProtection() {
1595                 // Can't protect pages in special namespaces
1596                 if ( $this->getNamespace() < 0 ) {
1597                         return false;
1598                 }
1599
1600                 // Can't protect pages that exist.
1601                 if ( $this->exists() ) {
1602                         return false;
1603                 }
1604
1605                 if ( !isset( $this->mTitleProtection ) ) {
1606                         $dbr = wfGetDB( DB_SLAVE );
1607                         $res = $dbr->select( 'protected_titles', '*',
1608                                 array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
1609                                 __METHOD__ );
1610
1611                         // fetchRow returns false if there are no rows.
1612                         $this->mTitleProtection = $dbr->fetchRow( $res );
1613                 }
1614                 return $this->mTitleProtection;
1615         }
1616
1617         /**
1618          * Update the title protection status
1619          *
1620          * @param $create_perm \type{\string} Permission required for creation
1621          * @param $reason \type{\string} Reason for protection
1622          * @param $expiry \type{\string} Expiry timestamp
1623          * @return boolean true
1624          */
1625         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
1626                 global $wgUser, $wgContLang;
1627
1628                 if ( $create_perm == implode( ',', $this->getRestrictions( 'create' ) )
1629                         && $expiry == $this->mRestrictionsExpiry['create'] ) {
1630                         // No change
1631                         return true;
1632                 }
1633
1634                 list ( $namespace, $title ) = array( $this->getNamespace(), $this->getDBkey() );
1635
1636                 $dbw = wfGetDB( DB_MASTER );
1637
1638                 $encodedExpiry = Block::encodeExpiry( $expiry, $dbw );
1639
1640                 $expiry_description = '';
1641                 if ( $encodedExpiry != 'infinity' ) {
1642                         $expiry_description = ' (' . wfMsgForContent( 'protect-expiring', $wgContLang->timeanddate( $expiry ),
1643                                 $wgContLang->date( $expiry ) , $wgContLang->time( $expiry ) ) . ')';
1644                 } else {
1645                         $expiry_description .= ' (' . wfMsgForContent( 'protect-expiry-indefinite' ) . ')';
1646                 }
1647
1648                 # Update protection table
1649                 if ( $create_perm != '' ) {
1650                         $dbw->replace( 'protected_titles', array( array( 'pt_namespace', 'pt_title' ) ),
1651                                 array(
1652                                         'pt_namespace' => $namespace,
1653                                         'pt_title' => $title,
1654                                         'pt_create_perm' => $create_perm,
1655                                         'pt_timestamp' => Block::encodeExpiry( wfTimestampNow(), $dbw ),
1656                                         'pt_expiry' => $encodedExpiry,
1657                                         'pt_user' => $wgUser->getId(),
1658                                         'pt_reason' => $reason,
1659                                 ), __METHOD__
1660                         );
1661                 } else {
1662                         $dbw->delete( 'protected_titles', array( 'pt_namespace' => $namespace,
1663                                 'pt_title' => $title ), __METHOD__ );
1664                 }
1665                 # Update the protection log
1666                 if ( $dbw->affectedRows() ) {
1667                         $log = new LogPage( 'protect' );
1668
1669                         if ( $create_perm ) {
1670                                 $params = array( "[create=$create_perm] $expiry_description", '' );
1671                                 $log->addEntry( ( isset( $this->mRestrictions['create'] ) && $this->mRestrictions['create'] ) ? 'modify' : 'protect', $this, trim( $reason ), $params );
1672                         } else {
1673                                 $log->addEntry( 'unprotect', $this, $reason );
1674                         }
1675                 }
1676
1677                 return true;
1678         }
1679
1680         /**
1681          * Remove any title protection due to page existing
1682          */
1683         public function deleteTitleProtection() {
1684                 $dbw = wfGetDB( DB_MASTER );
1685
1686                 $dbw->delete(
1687                         'protected_titles',
1688                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
1689                         __METHOD__
1690                 );
1691         }
1692
1693         /**
1694          * Would anybody with sufficient privileges be able to move this page?
1695          * Some pages just aren't movable.
1696          *
1697          * @return \type{\bool} TRUE or FALSE
1698          */
1699         public function isMovable() {
1700                 return MWNamespace::isMovable( $this->getNamespace() ) && $this->getInterwiki() == '';
1701         }
1702
1703         /**
1704          * Can $wgUser read this page?
1705          *
1706          * @return \type{\bool}
1707          * @todo fold these checks into userCan()
1708          */
1709         public function userCanRead() {
1710                 global $wgUser, $wgGroupPermissions;
1711
1712                 static $useShortcut = null;
1713
1714                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
1715                 if ( is_null( $useShortcut ) ) {
1716                         global $wgRevokePermissions;
1717                         $useShortcut = true;
1718                         if ( empty( $wgGroupPermissions['*']['read'] ) ) {
1719                                 # Not a public wiki, so no shortcut
1720                                 $useShortcut = false;
1721                         } elseif ( !empty( $wgRevokePermissions ) ) {
1722                                 /*
1723                                  * Iterate through each group with permissions being revoked (key not included since we don't care
1724                                  * what the group name is), then check if the read permission is being revoked. If it is, then
1725                                  * we don't use the shortcut below since the user might not be able to read, even though anon
1726                                  * reading is allowed.
1727                                  */
1728                                 foreach ( $wgRevokePermissions as $perms ) {
1729                                         if ( !empty( $perms['read'] ) ) {
1730                                                 # We might be removing the read right from the user, so no shortcut
1731                                                 $useShortcut = false;
1732                                                 break;
1733                                         }
1734                                 }
1735                         }
1736                 }
1737
1738                 $result = null;
1739                 wfRunHooks( 'userCan', array( &$this, &$wgUser, 'read', &$result ) );
1740                 if ( $result !== null ) {
1741                         return $result;
1742                 }
1743
1744                 # Shortcut for public wikis, allows skipping quite a bit of code
1745                 if ( $useShortcut ) {
1746                         return true;
1747                 }
1748
1749                 if ( $wgUser->isAllowed( 'read' ) ) {
1750                         return true;
1751                 } else {
1752                         global $wgWhitelistRead;
1753
1754                         /**
1755                          * Always grant access to the login page.
1756                          * Even anons need to be able to log in.
1757                         */
1758                         if ( $this->isSpecial( 'Userlogin' ) || $this->isSpecial( 'Resetpass' ) ) {
1759                                 return true;
1760                         }
1761
1762                         /**
1763                          * Bail out if there isn't whitelist
1764                          */
1765                         if ( !is_array( $wgWhitelistRead ) ) {
1766                                 return false;
1767                         }
1768
1769                         /**
1770                          * Check for explicit whitelisting
1771                          */
1772                         $name = $this->getPrefixedText();
1773                         $dbName = $this->getPrefixedDBKey();
1774                         // Check with and without underscores
1775                         if ( in_array( $name, $wgWhitelistRead, true ) || in_array( $dbName, $wgWhitelistRead, true ) )
1776                                 return true;
1777
1778                         /**
1779                          * Old settings might have the title prefixed with
1780                          * a colon for main-namespace pages
1781                          */
1782                         if ( $this->getNamespace() == NS_MAIN ) {
1783                                 if ( in_array( ':' . $name, $wgWhitelistRead ) ) {
1784                                         return true;
1785                                 }
1786                         }
1787
1788                         /**
1789                          * If it's a special page, ditch the subpage bit
1790                          * and check again
1791                          */
1792                         if ( $this->getNamespace() == NS_SPECIAL ) {
1793                                 $name = $this->getDBkey();
1794                                 list( $name, /* $subpage */ ) = SpecialPage::resolveAliasWithSubpage( $name );
1795                                 if ( $name === false ) {
1796                                         # Invalid special page, but we show standard login required message
1797                                         return false;
1798                                 }
1799
1800                                 $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
1801                                 if ( in_array( $pure, $wgWhitelistRead, true ) ) {
1802                                         return true;
1803                                 }
1804                         }
1805
1806                 }
1807                 return false;
1808         }
1809
1810         /**
1811          * Is this a talk page of some sort?
1812          *
1813          * @return \type{\bool}
1814          */
1815         public function isTalkPage() {
1816                 return MWNamespace::isTalk( $this->getNamespace() );
1817         }
1818
1819         /**
1820          * Is this a subpage?
1821          *
1822          * @return \type{\bool}
1823          */
1824         public function isSubpage() {
1825                 return MWNamespace::hasSubpages( $this->mNamespace )
1826                         ? strpos( $this->getText(), '/' ) !== false
1827                         : false;
1828         }
1829
1830         /**
1831          * Does this have subpages?  (Warning, usually requires an extra DB query.)
1832          *
1833          * @return \type{\bool}
1834          */
1835         public function hasSubpages() {
1836                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1837                         # Duh
1838                         return false;
1839                 }
1840
1841                 # We dynamically add a member variable for the purpose of this method
1842                 # alone to cache the result.  There's no point in having it hanging
1843                 # around uninitialized in every Title object; therefore we only add it
1844                 # if needed and don't declare it statically.
1845                 if ( isset( $this->mHasSubpages ) ) {
1846                         return $this->mHasSubpages;
1847                 }
1848
1849                 $subpages = $this->getSubpages( 1 );
1850                 if ( $subpages instanceof TitleArray ) {
1851                         return $this->mHasSubpages = (bool)$subpages->count();
1852                 }
1853                 return $this->mHasSubpages = false;
1854         }
1855
1856         /**
1857          * Get all subpages of this page.
1858          *
1859          * @param $limit Maximum number of subpages to fetch; -1 for no limit
1860          * @return mixed TitleArray, or empty array if this page's namespace
1861          *  doesn't allow subpages
1862          */
1863         public function getSubpages( $limit = -1 ) {
1864                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
1865                         return array();
1866                 }
1867
1868                 $dbr = wfGetDB( DB_SLAVE );
1869                 $conds['page_namespace'] = $this->getNamespace();
1870                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
1871                 $options = array();
1872                 if ( $limit > -1 ) {
1873                         $options['LIMIT'] = $limit;
1874                 }
1875                 return $this->mSubpages = TitleArray::newFromResult(
1876                         $dbr->select( 'page',
1877                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
1878                                 $conds,
1879                                 __METHOD__,
1880                                 $options
1881                         )
1882                 );
1883         }
1884
1885         /**
1886          * Could this page contain custom CSS or JavaScript, based
1887          * on the title?
1888          *
1889          * @return \type{\bool}
1890          */
1891         public function isCssOrJsPage() {
1892                 return $this->mNamespace == NS_MEDIAWIKI
1893                         && preg_match( '!\.(?:css|js)$!u', $this->mTextform ) > 0;
1894         }
1895
1896         /**
1897          * Is this a .css or .js subpage of a user page?
1898          * @return \type{\bool}
1899          */
1900         public function isCssJsSubpage() {
1901                 return ( NS_USER == $this->mNamespace and preg_match( "/\\/.*\\.(?:css|js)$/", $this->mTextform ) );
1902         }
1903
1904         /**
1905          * Is this a *valid* .css or .js subpage of a user page?
1906          * Check that the corresponding skin exists
1907          *
1908          * @return \type{\bool}
1909          */
1910         public function isValidCssJsSubpage() {
1911                 if ( $this->isCssJsSubpage() ) {
1912                         $name = $this->getSkinFromCssJsSubpage();
1913                         if ( $name == 'common' ) {
1914                                 return true;
1915                         }
1916                         $skinNames = Skin::getSkinNames();
1917                         return array_key_exists( $name, $skinNames );
1918                 } else {
1919                         return false;
1920                 }
1921         }
1922
1923         /**
1924          * Trim down a .css or .js subpage title to get the corresponding skin name
1925          *
1926          * @return string containing skin name from .css or .js subpage title
1927          */
1928         public function getSkinFromCssJsSubpage() {
1929                 $subpage = explode( '/', $this->mTextform );
1930                 $subpage = $subpage[ count( $subpage ) - 1 ];
1931                 return( str_replace( array( '.css', '.js' ), array( '', '' ), $subpage ) );
1932         }
1933
1934         /**
1935          * Is this a .css subpage of a user page?
1936          *
1937          * @return \type{\bool}
1938          */
1939         public function isCssSubpage() {
1940                 return ( NS_USER == $this->mNamespace && preg_match( "/\\/.*\\.css$/", $this->mTextform ) );
1941         }
1942
1943         /**
1944          * Is this a .js subpage of a user page?
1945          *
1946          * @return \type{\bool}
1947          */
1948         public function isJsSubpage() {
1949                 return ( NS_USER == $this->mNamespace && preg_match( "/\\/.*\\.js$/", $this->mTextform ) );
1950         }
1951
1952         /**
1953          * Protect css subpages of user pages: can $wgUser edit
1954          * this page?
1955          *
1956          * @return \type{\bool}
1957          * @todo XXX: this might be better using restrictions
1958          */
1959         public function userCanEditCssSubpage() {
1960                 global $wgUser;
1961                 return ( ( $wgUser->isAllowed( 'editusercssjs' ) && $wgUser->isAllowed( 'editusercss' ) )
1962                         || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
1963         }
1964
1965         /**
1966          * Protect js subpages of user pages: can $wgUser edit
1967          * this page?
1968          *
1969          * @return \type{\bool}
1970          * @todo XXX: this might be better using restrictions
1971          */
1972         public function userCanEditJsSubpage() {
1973                 global $wgUser;
1974                 return ( ( $wgUser->isAllowed( 'editusercssjs' ) && $wgUser->isAllowed( 'edituserjs' ) )
1975                        || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
1976         }
1977
1978         /**
1979          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
1980          *
1981          * @return \type{\bool} If the page is subject to cascading restrictions.
1982          */
1983         public function isCascadeProtected() {
1984                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
1985                 return ( $sources > 0 );
1986         }
1987
1988         /**
1989          * Cascading protection: Get the source of any cascading restrictions on this page.
1990          *
1991          * @param $getPages \type{\bool} Whether or not to retrieve the actual pages
1992          *        that the restrictions have come from.
1993          * @return \type{\arrayof{mixed title array, restriction array}} Array of the Title
1994          *         objects of the pages from which cascading restrictions have come,
1995          *         false for none, or true if such restrictions exist, but $getPages was not set.
1996          *         The restriction array is an array of each type, each of which contains a
1997          *         array of unique groups.
1998          */
1999         public function getCascadeProtectionSources( $getPages = true ) {
2000                 $pagerestrictions = array();
2001
2002                 if ( isset( $this->mCascadeSources ) && $getPages ) {
2003                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
2004                 } else if ( isset( $this->mHasCascadingRestrictions ) && !$getPages ) {
2005                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
2006                 }
2007
2008                 wfProfileIn( __METHOD__ );
2009
2010                 $dbr = wfGetDB( DB_SLAVE );
2011
2012                 if ( $this->getNamespace() == NS_FILE ) {
2013                         $tables = array( 'imagelinks', 'page_restrictions' );
2014                         $where_clauses = array(
2015                                 'il_to' => $this->getDBkey(),
2016                                 'il_from=pr_page',
2017                                 'pr_cascade' => 1
2018                         );
2019                 } else {
2020                         $tables = array( 'templatelinks', 'page_restrictions' );
2021                         $where_clauses = array(
2022                                 'tl_namespace' => $this->getNamespace(),
2023                                 'tl_title' => $this->getDBkey(),
2024                                 'tl_from=pr_page',
2025                                 'pr_cascade' => 1
2026                         );
2027                 }
2028
2029                 if ( $getPages ) {
2030                         $cols = array( 'pr_page', 'page_namespace', 'page_title',
2031                                                    'pr_expiry', 'pr_type', 'pr_level' );
2032                         $where_clauses[] = 'page_id=pr_page';
2033                         $tables[] = 'page';
2034                 } else {
2035                         $cols = array( 'pr_expiry' );
2036                 }
2037
2038                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
2039
2040                 $sources = $getPages ? array() : false;
2041                 $now = wfTimestampNow();
2042                 $purgeExpired = false;
2043
2044                 foreach ( $res as $row ) {
2045                         $expiry = Block::decodeExpiry( $row->pr_expiry );
2046                         if ( $expiry > $now ) {
2047                                 if ( $getPages ) {
2048                                         $page_id = $row->pr_page;
2049                                         $page_ns = $row->page_namespace;
2050                                         $page_title = $row->page_title;
2051                                         $sources[$page_id] = Title::makeTitle( $page_ns, $page_title );
2052                                         # Add groups needed for each restriction type if its not already there
2053                                         # Make sure this restriction type still exists
2054
2055                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
2056                                                 $pagerestrictions[$row->pr_type] = array();
2057                                         }
2058
2059                                         if ( isset( $pagerestrictions[$row->pr_type] ) &&
2060                                                  !in_array( $row->pr_level, $pagerestrictions[$row->pr_type] ) ) {
2061                                                 $pagerestrictions[$row->pr_type][] = $row->pr_level;
2062                                         }
2063                                 } else {
2064                                         $sources = true;
2065                                 }
2066                         } else {
2067                                 // Trigger lazy purge of expired restrictions from the db
2068                                 $purgeExpired = true;
2069                         }
2070                 }
2071                 if ( $purgeExpired ) {
2072                         Title::purgeExpiredRestrictions();
2073                 }
2074
2075                 wfProfileOut( __METHOD__ );
2076
2077                 if ( $getPages ) {
2078                         $this->mCascadeSources = $sources;
2079                         $this->mCascadingRestrictions = $pagerestrictions;
2080                 } else {
2081                         $this->mHasCascadingRestrictions = $sources;
2082                 }
2083
2084                 return array( $sources, $pagerestrictions );
2085         }
2086
2087         /**
2088          * Returns cascading restrictions for the current article
2089          *
2090          * @return Boolean
2091          */
2092         function areRestrictionsCascading() {
2093                 if ( !$this->mRestrictionsLoaded ) {
2094                         $this->loadRestrictions();
2095                 }
2096
2097                 return $this->mCascadeRestriction;
2098         }
2099
2100         /**
2101          * Loads a string into mRestrictions array
2102          *
2103          * @param $res \type{Resource} restrictions as an SQL result.
2104          * @param $oldFashionedRestrictions string comma-separated list of page
2105          *        restrictions from page table (pre 1.10)
2106          */
2107         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
2108                 $rows = array();
2109
2110                 foreach ( $res as $row ) {
2111                         $rows[] = $row;
2112                 }
2113
2114                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
2115         }
2116
2117         /**
2118          * Compiles list of active page restrictions from both page table (pre 1.10)
2119          * and page_restrictions table
2120          *
2121          * @param $rows array of db result objects
2122          * @param $oldFashionedRestrictions string comma-separated list of page
2123          *        restrictions from page table (pre 1.10)
2124          */
2125         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
2126                 $dbr = wfGetDB( DB_SLAVE );
2127
2128                 $restrictionTypes = $this->getRestrictionTypes();
2129
2130                 foreach ( $restrictionTypes as $type ) {
2131                         $this->mRestrictions[$type] = array();
2132                         $this->mRestrictionsExpiry[$type] = Block::decodeExpiry( '' );
2133                 }
2134
2135                 $this->mCascadeRestriction = false;
2136
2137                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2138
2139                 if ( $oldFashionedRestrictions === null ) {
2140                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2141                                 array( 'page_id' => $this->getArticleId() ), __METHOD__ );
2142                 }
2143
2144                 if ( $oldFashionedRestrictions != '' ) {
2145
2146                         foreach ( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2147                                 $temp = explode( '=', trim( $restrict ) );
2148                                 if ( count( $temp ) == 1 ) {
2149                                         // old old format should be treated as edit/move restriction
2150                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2151                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2152                                 } else {
2153                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
2154                                 }
2155                         }
2156
2157                         $this->mOldRestrictions = true;
2158
2159                 }
2160
2161                 if ( count( $rows ) ) {
2162                         # Current system - load second to make them override.
2163                         $now = wfTimestampNow();
2164                         $purgeExpired = false;
2165
2166                         foreach ( $rows as $row ) {
2167                                 # Cycle through all the restrictions.
2168
2169                                 // Don't take care of restrictions types that aren't allowed
2170
2171                                 if ( !in_array( $row->pr_type, $restrictionTypes ) )
2172                                         continue;
2173
2174                                 // This code should be refactored, now that it's being used more generally,
2175                                 // But I don't really see any harm in leaving it in Block for now -werdna
2176                                 $expiry = Block::decodeExpiry( $row->pr_expiry );
2177
2178                                 // Only apply the restrictions if they haven't expired!
2179                                 if ( !$expiry || $expiry > $now ) {
2180                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2181                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2182
2183                                         $this->mCascadeRestriction |= $row->pr_cascade;
2184                                 } else {
2185                                         // Trigger a lazy purge of expired restrictions
2186                                         $purgeExpired = true;
2187                                 }
2188                         }
2189
2190                         if ( $purgeExpired ) {
2191                                 Title::purgeExpiredRestrictions();
2192                         }
2193                 }
2194
2195                 $this->mRestrictionsLoaded = true;
2196         }
2197
2198         /**
2199          * Load restrictions from the page_restrictions table
2200          *
2201          * @param $oldFashionedRestrictions string comma-separated list of page
2202          *        restrictions from page table (pre 1.10)
2203          */
2204         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2205                 if ( !$this->mRestrictionsLoaded ) {
2206                         if ( $this->exists() ) {
2207                                 $dbr = wfGetDB( DB_SLAVE );
2208
2209                                 $res = $dbr->select( 'page_restrictions', '*',
2210                                         array( 'pr_page' => $this->getArticleId() ), __METHOD__ );
2211
2212                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2213                         } else {
2214                                 $title_protection = $this->getTitleProtection();
2215
2216                                 if ( $title_protection ) {
2217                                         $now = wfTimestampNow();
2218                                         $expiry = Block::decodeExpiry( $title_protection['pt_expiry'] );
2219
2220                                         if ( !$expiry || $expiry > $now ) {
2221                                                 // Apply the restrictions
2222                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2223                                                 $this->mRestrictions['create'] = explode( ',', trim( $title_protection['pt_create_perm'] ) );
2224                                         } else { // Get rid of the old restrictions
2225                                                 Title::purgeExpiredRestrictions();
2226                                         }
2227                                 } else {
2228                                         $this->mRestrictionsExpiry['create'] = Block::decodeExpiry( '' );
2229                                 }
2230                                 $this->mRestrictionsLoaded = true;
2231                         }
2232                 }
2233         }
2234
2235         /**
2236          * Purge expired restrictions from the page_restrictions table
2237          */
2238         static function purgeExpiredRestrictions() {
2239                 $dbw = wfGetDB( DB_MASTER );
2240                 $dbw->delete(
2241                         'page_restrictions',
2242                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2243                         __METHOD__
2244                 );
2245
2246                 $dbw->delete(
2247                         'protected_titles',
2248                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2249                         __METHOD__
2250                 );
2251         }
2252
2253         /**
2254          * Accessor/initialisation for mRestrictions
2255          *
2256          * @param $action \type{\string} action that permission needs to be checked for
2257          * @return \type{\arrayof{\string}} the array of groups allowed to edit this article
2258          */
2259         public function getRestrictions( $action ) {
2260                 if ( !$this->mRestrictionsLoaded ) {
2261                         $this->loadRestrictions();
2262                 }
2263                 return isset( $this->mRestrictions[$action] )
2264                                 ? $this->mRestrictions[$action]
2265                                 : array();
2266         }
2267
2268         /**
2269          * Get the expiry time for the restriction against a given action
2270          *
2271          * @return 14-char timestamp, or 'infinity' if the page is protected forever
2272          *      or not protected at all, or false if the action is not recognised.
2273          */
2274         public function getRestrictionExpiry( $action ) {
2275                 if ( !$this->mRestrictionsLoaded ) {
2276                         $this->loadRestrictions();
2277                 }
2278                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2279         }
2280
2281         /**
2282          * Is there a version of this page in the deletion archive?
2283          *
2284          * @return \type{\int} the number of archived revisions
2285          */
2286         public function isDeleted() {
2287                 if ( $this->getNamespace() < 0 ) {
2288                         $n = 0;
2289                 } else {
2290                         $dbr = wfGetDB( DB_SLAVE );
2291                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2292                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2293                                 __METHOD__
2294                         );
2295                         if ( $this->getNamespace() == NS_FILE ) {
2296                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2297                                         array( 'fa_name' => $this->getDBkey() ),
2298                                         __METHOD__
2299                                 );
2300                         }
2301                 }
2302                 return (int)$n;
2303         }
2304
2305         /**
2306          * Is there a version of this page in the deletion archive?
2307          *
2308          * @return Boolean
2309          */
2310         public function isDeletedQuick() {
2311                 if ( $this->getNamespace() < 0 ) {
2312                         return false;
2313                 }
2314                 $dbr = wfGetDB( DB_SLAVE );
2315                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2316                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2317                         __METHOD__
2318                 );
2319                 if ( !$deleted && $this->getNamespace() == NS_FILE ) {
2320                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2321                                 array( 'fa_name' => $this->getDBkey() ),
2322                                 __METHOD__
2323                         );
2324                 }
2325                 return $deleted;
2326         }
2327
2328         /**
2329          * Get the article ID for this Title from the link cache,
2330          * adding it if necessary
2331          *
2332          * @param $flags \type{\int} a bit field; may be Title::GAID_FOR_UPDATE to select
2333          *  for update
2334          * @return \type{\int} the ID
2335          */
2336         public function getArticleID( $flags = 0 ) {
2337                 if ( $this->getNamespace() < 0 ) {
2338                         return $this->mArticleID = 0;
2339                 }
2340                 $linkCache = LinkCache::singleton();
2341                 if ( $flags & self::GAID_FOR_UPDATE ) {
2342                         $oldUpdate = $linkCache->forUpdate( true );
2343                         $linkCache->clearLink( $this );
2344                         $this->mArticleID = $linkCache->addLinkObj( $this );
2345                         $linkCache->forUpdate( $oldUpdate );
2346                 } else {
2347                         if ( -1 == $this->mArticleID ) {
2348                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2349                         }
2350                 }
2351                 return $this->mArticleID;
2352         }
2353
2354         /**
2355          * Is this an article that is a redirect page?
2356          * Uses link cache, adding it if necessary
2357          *
2358          * @param $flags \type{\int} a bit field; may be Title::GAID_FOR_UPDATE to select for update
2359          * @return \type{\bool}
2360          */
2361         public function isRedirect( $flags = 0 ) {
2362                 if ( !is_null( $this->mRedirect ) ) {
2363                         return $this->mRedirect;
2364                 }
2365                 # Calling getArticleID() loads the field from cache as needed
2366                 if ( !$this->getArticleID( $flags ) ) {
2367                         return $this->mRedirect = false;
2368                 }
2369                 $linkCache = LinkCache::singleton();
2370                 $this->mRedirect = (bool)$linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2371
2372                 return $this->mRedirect;
2373         }
2374
2375         /**
2376          * What is the length of this page?
2377          * Uses link cache, adding it if necessary
2378          *
2379          * @param $flags \type{\int} a bit field; may be Title::GAID_FOR_UPDATE to select for update
2380          * @return \type{\bool}
2381          */
2382         public function getLength( $flags = 0 ) {
2383                 if ( $this->mLength != -1 ) {
2384                         return $this->mLength;
2385                 }
2386                 # Calling getArticleID() loads the field from cache as needed
2387                 if ( !$this->getArticleID( $flags ) ) {
2388                         return $this->mLength = 0;
2389                 }
2390                 $linkCache = LinkCache::singleton();
2391                 $this->mLength = intval( $linkCache->getGoodLinkFieldObj( $this, 'length' ) );
2392
2393                 return $this->mLength;
2394         }
2395
2396         /**
2397          * What is the page_latest field for this page?
2398          *
2399          * @param $flags \type{\int} a bit field; may be Title::GAID_FOR_UPDATE to select for update
2400          * @return \type{\int} or 0 if the page doesn't exist
2401          */
2402         public function getLatestRevID( $flags = 0 ) {
2403                 if ( $this->mLatestID !== false ) {
2404                         return intval( $this->mLatestID );
2405                 }
2406                 # Calling getArticleID() loads the field from cache as needed
2407                 if ( !$this->getArticleID( $flags ) ) {
2408                         return $this->mLatestID = 0;
2409                 }
2410                 $linkCache = LinkCache::singleton();
2411                 $this->mLatestID = intval( $linkCache->getGoodLinkFieldObj( $this, 'revision' ) );
2412
2413                 return $this->mLatestID;
2414         }
2415
2416         /**
2417          * This clears some fields in this object, and clears any associated
2418          * keys in the "bad links" section of the link cache.
2419          *
2420          * - This is called from Article::insertNewArticle() to allow
2421          * loading of the new page_id. It's also called from
2422          * Article::doDeleteArticle()
2423          *
2424          * @param $newid \type{\int} the new Article ID
2425          */
2426         public function resetArticleID( $newid ) {
2427                 $linkCache = LinkCache::singleton();
2428                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
2429
2430                 if ( $newid === false ) {
2431                         $this->mArticleID = -1;
2432                 } else {
2433                         $this->mArticleID = intval( $newid );
2434                 }
2435                 $this->mRestrictionsLoaded = false;
2436                 $this->mRestrictions = array();
2437                 $this->mRedirect = null;
2438                 $this->mLength = -1;
2439                 $this->mLatestID = false;
2440         }
2441
2442         /**
2443          * Updates page_touched for this page; called from LinksUpdate.php
2444          *
2445          * @return \type{\bool} true if the update succeded
2446          */
2447         public function invalidateCache() {
2448                 if ( wfReadOnly() ) {
2449                         return;
2450                 }
2451                 $dbw = wfGetDB( DB_MASTER );
2452                 $success = $dbw->update(
2453                         'page',
2454                         array( 'page_touched' => $dbw->timestamp() ),
2455                         $this->pageCond(),
2456                         __METHOD__
2457                 );
2458                 HTMLFileCache::clearFileCache( $this );
2459                 return $success;
2460         }
2461
2462         /**
2463          * Prefix some arbitrary text with the namespace or interwiki prefix
2464          * of this object
2465          *
2466          * @param $name \type{\string} the text
2467          * @return \type{\string} the prefixed text
2468          * @private
2469          */
2470         /* private */ function prefix( $name ) {
2471                 $p = '';
2472                 if ( $this->mInterwiki != '' ) {
2473                         $p = $this->mInterwiki . ':';
2474                 }
2475                 if ( 0 != $this->mNamespace ) {
2476                         $p .= $this->getNsText() . ':';
2477                 }
2478                 return $p . $name;
2479         }
2480
2481         /**
2482          * Returns a simple regex that will match on characters and sequences invalid in titles.
2483          * Note that this doesn't pick up many things that could be wrong with titles, but that
2484          * replacing this regex with something valid will make many titles valid.
2485          *
2486          * @return string regex string
2487          */
2488         static function getTitleInvalidRegex() {
2489                 static $rxTc = false;
2490                 if ( !$rxTc ) {
2491                         # Matching titles will be held as illegal.
2492                         $rxTc = '/' .
2493                                 # Any character not allowed is forbidden...
2494                                 '[^' . Title::legalChars() . ']' .
2495                                 # URL percent encoding sequences interfere with the ability
2496                                 # to round-trip titles -- you can't link to them consistently.
2497                                 '|%[0-9A-Fa-f]{2}' .
2498                                 # XML/HTML character references produce similar issues.
2499                                 '|&[A-Za-z0-9\x80-\xff]+;' .
2500                                 '|&#[0-9]+;' .
2501                                 '|&#x[0-9A-Fa-f]+;' .
2502                                 '/S';
2503                 }
2504
2505                 return $rxTc;
2506         }
2507
2508         /**
2509          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
2510          *
2511          * @param $text string containing title to capitalize
2512          * @param $ns int namespace index, defaults to NS_MAIN
2513          * @return String containing capitalized title
2514          */
2515         public static function capitalize( $text, $ns = NS_MAIN ) {
2516                 global $wgContLang;
2517
2518                 if ( MWNamespace::isCapitalized( $ns ) ) {
2519                         return $wgContLang->ucfirst( $text );
2520                 } else {
2521                         return $text;
2522                 }
2523         }
2524
2525         /**
2526          * Secure and split - main initialisation function for this object
2527          *
2528          * Assumes that mDbkeyform has been set, and is urldecoded
2529          * and uses underscores, but not otherwise munged.  This function
2530          * removes illegal characters, splits off the interwiki and
2531          * namespace prefixes, sets the other forms, and canonicalizes
2532          * everything.
2533          *
2534          * @return \type{\bool} true on success
2535          */
2536         private function secureAndSplit() {
2537                 global $wgContLang, $wgLocalInterwiki;
2538
2539                 # Initialisation
2540                 $rxTc = self::getTitleInvalidRegex();
2541
2542                 $this->mInterwiki = $this->mFragment = '';
2543                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2544
2545                 $dbkey = $this->mDbkeyform;
2546
2547                 # Strip Unicode bidi override characters.
2548                 # Sometimes they slip into cut-n-pasted page titles, where the
2549                 # override chars get included in list displays.
2550                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
2551
2552                 # Clean up whitespace
2553                 # Note: use of the /u option on preg_replace here will cause
2554                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
2555                 # conveniently disabling them.
2556                 #
2557                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
2558                 $dbkey = trim( $dbkey, '_' );
2559
2560                 if ( $dbkey == '' ) {
2561                         return false;
2562                 }
2563
2564                 if ( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2565                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2566                         return false;
2567                 }
2568
2569                 $this->mDbkeyform = $dbkey;
2570
2571                 # Initial colon indicates main namespace rather than specified default
2572                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
2573                 if ( ':' == $dbkey { 0 } ) {
2574                         $this->mNamespace = NS_MAIN;
2575                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
2576                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
2577                 }
2578
2579                 # Namespace or interwiki prefix
2580                 $firstPass = true;
2581                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
2582                 do {
2583                         $m = array();
2584                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
2585                                 $p = $m[1];
2586                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
2587                                         # Ordinary namespace
2588                                         $dbkey = $m[2];
2589                                         $this->mNamespace = $ns;
2590                                         # For Talk:X pages, check if X has a "namespace" prefix
2591                                         if ( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
2592                                                 if ( $wgContLang->getNsIndex( $x[1] ) ) {
2593                                                         return false; # Disallow Talk:File:x type titles...
2594                                                 } else if ( Interwiki::isValidInterwiki( $x[1] ) ) {
2595                                                         return false; # Disallow Talk:Interwiki:x type titles...
2596                                                 }
2597                                         }
2598                                 } elseif ( Interwiki::isValidInterwiki( $p ) ) {
2599                                         if ( !$firstPass ) {
2600                                                 # Can't make a local interwiki link to an interwiki link.
2601                                                 # That's just crazy!
2602                                                 return false;
2603                                         }
2604
2605                                         # Interwiki link
2606                                         $dbkey = $m[2];
2607                                         $this->mInterwiki = $wgContLang->lc( $p );
2608
2609                                         # Redundant interwiki prefix to the local wiki
2610                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
2611                                                 if ( $dbkey == '' ) {
2612                                                         # Can't have an empty self-link
2613                                                         return false;
2614                                                 }
2615                                                 $this->mInterwiki = '';
2616                                                 $firstPass = false;
2617                                                 # Do another namespace split...
2618                                                 continue;
2619                                         }
2620
2621                                         # If there's an initial colon after the interwiki, that also
2622                                         # resets the default namespace
2623                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
2624                                                 $this->mNamespace = NS_MAIN;
2625                                                 $dbkey = substr( $dbkey, 1 );
2626                                         }
2627                                 }
2628                                 # If there's no recognized interwiki or namespace,
2629                                 # then let the colon expression be part of the title.
2630                         }
2631                         break;
2632                 } while ( true );
2633
2634                 # We already know that some pages won't be in the database!
2635                 #
2636                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
2637                         $this->mArticleID = 0;
2638                 }
2639                 $fragment = strstr( $dbkey, '#' );
2640                 if ( false !== $fragment ) {
2641                         $this->setFragment( preg_replace( '/^#_*/', '#', $fragment ) );
2642                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
2643                         # remove whitespace again: prevents "Foo_bar_#"
2644                         # becoming "Foo_bar_"
2645                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
2646                 }
2647
2648                 # Reject illegal characters.
2649                 #
2650                 if ( preg_match( $rxTc, $dbkey ) ) {
2651                         return false;
2652                 }
2653
2654                 /**
2655                  * Pages with "/./" or "/../" appearing in the URLs will often be un-
2656                  * reachable due to the way web browsers deal with 'relative' URLs.
2657                  * Also, they conflict with subpage syntax.  Forbid them explicitly.
2658                  */
2659                 if ( strpos( $dbkey, '.' ) !== false &&
2660                      ( $dbkey === '.' || $dbkey === '..' ||
2661                        strpos( $dbkey, './' ) === 0  ||
2662                        strpos( $dbkey, '../' ) === 0 ||
2663                        strpos( $dbkey, '/./' ) !== false ||
2664                        strpos( $dbkey, '/../' ) !== false  ||
2665                        substr( $dbkey, -2 ) == '/.' ||
2666                        substr( $dbkey, -3 ) == '/..' ) )
2667                 {
2668                         return false;
2669                 }
2670
2671                 /**
2672                  * Magic tilde sequences? Nu-uh!
2673                  */
2674                 if ( strpos( $dbkey, '~~~' ) !== false ) {
2675                         return false;
2676                 }
2677
2678                 /**
2679                  * Limit the size of titles to 255 bytes.
2680                  * This is typically the size of the underlying database field.
2681                  * We make an exception for special pages, which don't need to be stored
2682                  * in the database, and may edge over 255 bytes due to subpage syntax
2683                  * for long titles, e.g. [[Special:Block/Long name]]
2684                  */
2685                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
2686                   strlen( $dbkey ) > 512 )
2687                 {
2688                         return false;
2689                 }
2690
2691                 /**
2692                  * Normally, all wiki links are forced to have
2693                  * an initial capital letter so [[foo]] and [[Foo]]
2694                  * point to the same place.
2695                  *
2696                  * Don't force it for interwikis, since the other
2697                  * site might be case-sensitive.
2698                  */
2699                 $this->mUserCaseDBKey = $dbkey;
2700                 if ( $this->mInterwiki == '' ) {
2701                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
2702                 }
2703
2704                 /**
2705                  * Can't make a link to a namespace alone...
2706                  * "empty" local links can only be self-links
2707                  * with a fragment identifier.
2708                  */
2709                 if ( $dbkey == '' &&
2710                         $this->mInterwiki == '' &&
2711                         $this->mNamespace != NS_MAIN ) {
2712                         return false;
2713                 }
2714                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
2715                 // IP names are not allowed for accounts, and can only be referring to
2716                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
2717                 // there are numerous ways to present the same IP. Having sp:contribs scan
2718                 // them all is silly and having some show the edits and others not is
2719                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
2720                 $dbkey = ( $this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK ) ?
2721                         IP::sanitizeIP( $dbkey ) : $dbkey;
2722                 // Any remaining initial :s are illegal.
2723                 if ( $dbkey !== '' && ':' == $dbkey { 0 } ) {
2724                         return false;
2725                 }
2726
2727                 # Fill fields
2728                 $this->mDbkeyform = $dbkey;
2729                 $this->mUrlform = wfUrlencode( $dbkey );
2730
2731                 $this->mTextform = str_replace( '_', ' ', $dbkey );
2732
2733                 return true;
2734         }
2735
2736         /**
2737          * Set the fragment for this title. Removes the first character from the
2738          * specified fragment before setting, so it assumes you're passing it with
2739          * an initial "#".
2740          *
2741          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
2742          * Still in active use privately.
2743          *
2744          * @param $fragment \type{\string} text
2745          */
2746         public function setFragment( $fragment ) {
2747                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
2748         }
2749
2750         /**
2751          * Get a Title object associated with the talk page of this article
2752          *
2753          * @return \type{Title} the object for the talk page
2754          */
2755         public function getTalkPage() {
2756                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
2757         }
2758
2759         /**
2760          * Get a title object associated with the subject page of this
2761          * talk page
2762          *
2763          * @return \type{Title} the object for the subject page
2764          */
2765         public function getSubjectPage() {
2766                 // Is this the same title?
2767                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
2768                 if ( $this->getNamespace() == $subjectNS ) {
2769                         return $this;
2770                 }
2771                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
2772         }
2773
2774         /**
2775          * Get an array of Title objects linking to this Title
2776          * Also stores the IDs in the link cache.
2777          *
2778          * WARNING: do not use this function on arbitrary user-supplied titles!
2779          * On heavily-used templates it will max out the memory.
2780          *
2781          * @param $options Array: may be FOR UPDATE
2782          * @param $table String: table name
2783          * @param $prefix String: fields prefix
2784          * @return \type{\arrayof{Title}} the Title objects linking here
2785          */
2786         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
2787                 $linkCache = LinkCache::singleton();
2788
2789                 if ( count( $options ) > 0 ) {
2790                         $db = wfGetDB( DB_MASTER );
2791                 } else {
2792                         $db = wfGetDB( DB_SLAVE );
2793                 }
2794
2795                 $res = $db->select(
2796                         array( 'page', $table ),
2797                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ),
2798                         array(
2799                                 "{$prefix}_from=page_id",
2800                                 "{$prefix}_namespace" => $this->getNamespace(),
2801                                 "{$prefix}_title"     => $this->getDBkey() ),
2802                         __METHOD__,
2803                         $options
2804                 );
2805
2806                 $retVal = array();
2807                 if ( $db->numRows( $res ) ) {
2808                         foreach ( $res as $row ) {
2809                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
2810                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj, $row->page_len, $row->page_is_redirect, $row->page_latest );
2811                                         $retVal[] = $titleObj;
2812                                 }
2813                         }
2814                 }
2815                 return $retVal;
2816         }
2817
2818         /**
2819          * Get an array of Title objects using this Title as a template
2820          * Also stores the IDs in the link cache.
2821          *
2822          * WARNING: do not use this function on arbitrary user-supplied titles!
2823          * On heavily-used templates it will max out the memory.
2824          *
2825          * @param $options Array: may be FOR UPDATE
2826          * @return \type{\arrayof{Title}} the Title objects linking here
2827          */
2828         public function getTemplateLinksTo( $options = array() ) {
2829                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
2830         }
2831
2832         /**
2833          * Get an array of Title objects referring to non-existent articles linked from this page
2834          *
2835          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
2836          * @return \type{\arrayof{Title}} the Title objects
2837          */
2838         public function getBrokenLinksFrom() {
2839                 if ( $this->getArticleId() == 0 ) {
2840                         # All links from article ID 0 are false positives
2841                         return array();
2842                 }
2843
2844                 $dbr = wfGetDB( DB_SLAVE );
2845                 $res = $dbr->select(
2846                         array( 'page', 'pagelinks' ),
2847                         array( 'pl_namespace', 'pl_title' ),
2848                         array(
2849                                 'pl_from' => $this->getArticleId(),
2850                                 'page_namespace IS NULL'
2851                         ),
2852                         __METHOD__, array(),
2853                         array(
2854                                 'page' => array(
2855                                         'LEFT JOIN',
2856                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
2857                                 )
2858                         )
2859                 );
2860
2861                 $retVal = array();
2862                 foreach ( $res as $row ) {
2863                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
2864                 }
2865                 return $retVal;
2866         }
2867
2868
2869         /**
2870          * Get a list of URLs to purge from the Squid cache when this
2871          * page changes
2872          *
2873          * @return \type{\arrayof{\string}} the URLs
2874          */
2875         public function getSquidURLs() {
2876                 global $wgContLang;
2877
2878                 $urls = array(
2879                         $this->getInternalURL(),
2880                         $this->getInternalURL( 'action=history' )
2881                 );
2882
2883                 // purge variant urls as well
2884                 if ( $wgContLang->hasVariants() ) {
2885                         $variants = $wgContLang->getVariants();
2886                         foreach ( $variants as $vCode ) {
2887                                 $urls[] = $this->getInternalURL( '', $vCode );
2888                         }
2889                 }
2890
2891                 return $urls;
2892         }
2893
2894         /**
2895          * Purge all applicable Squid URLs
2896          */
2897         public function purgeSquid() {
2898                 global $wgUseSquid;
2899                 if ( $wgUseSquid ) {
2900                         $urls = $this->getSquidURLs();
2901                         $u = new SquidUpdate( $urls );
2902                         $u->doUpdate();
2903                 }
2904         }
2905
2906         /**
2907          * Move this page without authentication
2908          *
2909          * @param $nt \type{Title} the new page Title
2910          * @return \type{\mixed} true on success, getUserPermissionsErrors()-like array on failure
2911          */
2912         public function moveNoAuth( &$nt ) {
2913                 return $this->moveTo( $nt, false );
2914         }
2915
2916         /**
2917          * Check whether a given move operation would be valid.
2918          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
2919          *
2920          * @param $nt \type{Title} the new title
2921          * @param $auth \type{\bool} indicates whether $wgUser's permissions
2922          *  should be checked
2923          * @param $reason \type{\string} is the log summary of the move, used for spam checking
2924          * @return \type{\mixed} True on success, getUserPermissionsErrors()-like array on failure
2925          */
2926         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
2927                 global $wgUser;
2928
2929                 $errors = array();
2930                 if ( !$nt ) {
2931                         // Normally we'd add this to $errors, but we'll get
2932                         // lots of syntax errors if $nt is not an object
2933                         return array( array( 'badtitletext' ) );
2934                 }
2935                 if ( $this->equals( $nt ) ) {
2936                         $errors[] = array( 'selfmove' );
2937                 }
2938                 if ( !$this->isMovable() ) {
2939                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
2940                 }
2941                 if ( $nt->getInterwiki() != '' ) {
2942                         $errors[] = array( 'immobile-target-namespace-iw' );
2943                 }
2944                 if ( !$nt->isMovable() ) {
2945                         $errors[] = array( 'immobile-target-namespace', $nt->getNsText() );
2946                 }
2947
2948                 $oldid = $this->getArticleID();
2949                 $newid = $nt->getArticleID();
2950
2951                 if ( strlen( $nt->getDBkey() ) < 1 ) {
2952                         $errors[] = array( 'articleexists' );
2953                 }
2954                 if ( ( $this->getDBkey() == '' ) ||
2955                          ( !$oldid ) ||
2956                      ( $nt->getDBkey() == '' ) ) {
2957                         $errors[] = array( 'badarticleerror' );
2958                 }
2959
2960                 // Image-specific checks
2961                 if ( $this->getNamespace() == NS_FILE ) {
2962                         if ( $nt->getNamespace() != NS_FILE ) {
2963                                 $errors[] = array( 'imagenocrossnamespace' );
2964                         }
2965                         $file = wfLocalFile( $this );
2966                         if ( $file->exists() ) {
2967                                 if ( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
2968                                         $errors[] = array( 'imageinvalidfilename' );
2969                                 }
2970                                 if ( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
2971                                         $errors[] = array( 'imagetypemismatch' );
2972                                 }
2973                         }
2974                         $destfile = wfLocalFile( $nt );
2975                         if ( !$wgUser->isAllowed( 'reupload-shared' ) && !$destfile->exists() && wfFindFile( $nt ) ) {
2976                                 $errors[] = array( 'file-exists-sharedrepo' );
2977                         }
2978                 }
2979
2980                 if ( $nt->getNamespace() == NS_FILE && $this->getNamespace() != NS_FILE ) {
2981                         $errors[] = array( 'nonfile-cannot-move-to-file' );
2982                 }
2983
2984                 if ( $auth ) {
2985                         $errors = wfMergeErrorArrays( $errors,
2986                                 $this->getUserPermissionsErrors( 'move', $wgUser ),
2987                                 $this->getUserPermissionsErrors( 'edit', $wgUser ),
2988                                 $nt->getUserPermissionsErrors( 'move-target', $wgUser ),
2989                                 $nt->getUserPermissionsErrors( 'edit', $wgUser ) );
2990                 }
2991
2992                 $match = EditPage::matchSummarySpamRegex( $reason );
2993                 if ( $match !== false ) {
2994                         // This is kind of lame, won't display nice
2995                         $errors[] = array( 'spamprotectiontext' );
2996                 }
2997
2998                 $err = null;
2999                 if ( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
3000                         $errors[] = array( 'hookaborted', $err );
3001                 }
3002
3003                 # The move is allowed only if (1) the target doesn't exist, or
3004                 # (2) the target is a redirect to the source, and has no history
3005                 # (so we can undo bad moves right after they're done).
3006
3007                 if ( 0 != $newid ) { # Target exists; check for validity
3008                         if ( !$this->isValidMoveTarget( $nt ) ) {
3009                                 $errors[] = array( 'articleexists' );
3010                         }
3011                 } else {
3012                         $tp = $nt->getTitleProtection();
3013                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
3014                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
3015                                 $errors[] = array( 'cantmove-titleprotected' );
3016                         }
3017                 }
3018                 if ( empty( $errors ) ) {
3019                         return true;
3020                 }
3021                 return $errors;
3022         }
3023
3024         /**
3025          * Move a title to a new location
3026          *
3027          * @param $nt \type{Title} the new title
3028          * @param $auth \type{\bool} indicates whether $wgUser's permissions
3029          *  should be checked
3030          * @param $reason \type{\string} The reason for the move
3031          * @param $createRedirect \type{\bool} Whether to create a redirect from the old title to the new title.
3032          *  Ignored if the user doesn't have the suppressredirect right.
3033          * @return \type{\mixed} true on success, getUserPermissionsErrors()-like array on failure
3034          */
3035         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
3036                 global $wgContLang;
3037
3038                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
3039                 if ( is_array( $err ) ) {
3040                         return $err;
3041                 }
3042
3043                 // If it is a file, move it first. It is done before all other moving stuff is done because it's hard to revert
3044                 $dbw = wfGetDB( DB_MASTER );
3045                 if ( $this->getNamespace() == NS_FILE ) {
3046                         $file = wfLocalFile( $this );
3047                         if ( $file->exists() ) {
3048                                 $status = $file->move( $nt );
3049                                 if ( !$status->isOk() ) {
3050                                         return $status->getErrorsArray();
3051                                 }
3052                         }
3053                 }
3054
3055                 $pageid = $this->getArticleID();
3056                 $protected = $this->isProtected();
3057                 if ( $nt->exists() ) {
3058                         $err = $this->moveOverExistingRedirect( $nt, $reason, $createRedirect );
3059                         $pageCountChange = ( $createRedirect ? 0 : -1 );
3060                 } else { # Target didn't exist, do normal move.
3061                         $err = $this->moveToNewTitle( $nt, $reason, $createRedirect );
3062                         $pageCountChange = ( $createRedirect ? 1 : 0 );
3063                 }
3064
3065                 if ( is_array( $err ) ) {
3066                         return $err;
3067                 }
3068                 $redirid = $this->getArticleID();
3069
3070                 // Refresh the sortkey for this row.  Be careful to avoid resetting
3071                 // cl_timestamp, which may disturb time-based lists on some sites.
3072                 $prefix = $dbw->selectField(
3073                         'categorylinks',
3074                         'cl_sortkey_prefix',
3075                         array( 'cl_from' => $pageid ),
3076                         __METHOD__
3077                 );
3078                 $dbw->update( 'categorylinks',
3079                         array(
3080                                 'cl_sortkey' => $wgContLang->convertToSortkey( $nt->getCategorySortkey( $prefix ) ),
3081                                 'cl_timestamp=cl_timestamp' ),
3082                         array( 'cl_from' => $pageid ),
3083                         __METHOD__ );
3084
3085                 if ( $protected ) {
3086                         # Protect the redirect title as the title used to be...
3087                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
3088                                 array(
3089                                         'pr_page'    => $redirid,
3090                                         'pr_type'    => 'pr_type',
3091                                         'pr_level'   => 'pr_level',
3092                                         'pr_cascade' => 'pr_cascade',
3093                                         'pr_user'    => 'pr_user',
3094                                         'pr_expiry'  => 'pr_expiry'
3095                                 ),
3096                                 array( 'pr_page' => $pageid ),
3097                                 __METHOD__,
3098                                 array( 'IGNORE' )
3099                         );
3100                         # Update the protection log
3101                         $log = new LogPage( 'protect' );
3102                         $comment = wfMsgForContent( 'prot_1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
3103                         if ( $reason ) {
3104                                 $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3105                         }
3106                         $log->addEntry( 'move_prot', $nt, $comment, array( $this->getPrefixedText() ) ); // FIXME: $params?
3107                 }
3108
3109                 # Update watchlists
3110                 $oldnamespace = $this->getNamespace() & ~1;
3111                 $newnamespace = $nt->getNamespace() & ~1;
3112                 $oldtitle = $this->getDBkey();
3113                 $newtitle = $nt->getDBkey();
3114
3115                 if ( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
3116                         WatchedItem::duplicateEntries( $this, $nt );
3117                 }
3118
3119                 # Update search engine
3120                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
3121                 $u->doUpdate();
3122                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
3123                 $u->doUpdate();
3124
3125                 # Update site_stats
3126                 if ( $this->isContentPage() && !$nt->isContentPage() ) {
3127                         # No longer a content page
3128                         # Not viewed, edited, removing
3129                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange );
3130                 } elseif ( !$this->isContentPage() && $nt->isContentPage() ) {
3131                         # Now a content page
3132                         # Not viewed, edited, adding
3133                         $u = new SiteStatsUpdate( 0, 1, + 1, $pageCountChange );
3134                 } elseif ( $pageCountChange ) {
3135                         # Redirect added
3136                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
3137                 } else {
3138                         # Nothing special
3139                         $u = false;
3140                 }
3141                 if ( $u ) {
3142                         $u->doUpdate();
3143                 }
3144                 # Update message cache for interface messages
3145                 global $wgMessageCache;
3146                 if ( $this->getNamespace() == NS_MEDIAWIKI ) {
3147                         # @bug 17860: old article can be deleted, if this the case,
3148                         # delete it from message cache
3149                         if ( $this->getArticleID() === 0 ) {
3150                                 $wgMessageCache->replace( $this->getDBkey(), false );
3151                         } else {
3152                                 $oldarticle = new Article( $this );
3153                                 $wgMessageCache->replace( $this->getDBkey(), $oldarticle->getContent() );
3154                         }
3155                 }
3156                 if ( $nt->getNamespace() == NS_MEDIAWIKI ) {
3157                         $newarticle = new Article( $nt );
3158                         $wgMessageCache->replace( $nt->getDBkey(), $newarticle->getContent() );
3159                 }
3160
3161                 global $wgUser;
3162                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3163                 return true;
3164         }
3165
3166         /**
3167          * Move page to a title which is at present a redirect to the
3168          * source page
3169          *
3170          * @param $nt \type{Title} the page to move to, which should currently
3171          *  be a redirect
3172          * @param $reason \type{\string} The reason for the move
3173          * @param $createRedirect \type{\bool} Whether to leave a redirect at the old title.
3174          *  Ignored if the user doesn't have the suppressredirect right
3175          */
3176         private function moveOverExistingRedirect( &$nt, $reason = '', $createRedirect = true ) {
3177                 global $wgUseSquid, $wgUser, $wgContLang;
3178
3179                 $comment = wfMsgForContent( '1movedto2_redir', $this->getPrefixedText(), $nt->getPrefixedText() );
3180
3181                 if ( $reason ) {
3182                         $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
3183                 }
3184                 # Truncate for whole multibyte characters. +5 bytes for ellipsis
3185                 $comment = $wgContLang->truncate( $comment, 250 );
3186
3187                 $now = wfTimestampNow();
3188                 $newid = $nt->getArticleID();
3189                 $oldid = $this->getArticleID();
3190                 $latest = $this->getLatestRevID();
3191
3192                 $dbw = wfGetDB( DB_MASTER );
3193
3194                 $rcts = $dbw->timestamp( $nt->getEarliestRevTime() );
3195                 $newns = $nt->getNamespace();
3196                 $newdbk = $nt->getDBkey();
3197
3198                 # Delete the old redirect. We don't save it to history since
3199                 # by definition if we've got here it's rather uninteresting.
3200                 # We have to remove it so that the next step doesn't trigger
3201                 # a conflict on the unique namespace+title index...
3202                 $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3203                 if ( !$dbw->cascadingDeletes() ) {
3204                         $dbw->delete( 'revision', array( 'rev_page' => $newid ), __METHOD__ );
3205                         global $wgUseTrackbacks;
3206                         if ( $wgUseTrackbacks ) {
3207                                 $dbw->delete( 'trackbacks', array( 'tb_page' => $newid ), __METHOD__ );
3208                         }
3209                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
3210                         $dbw->delete( 'imagelinks', array( 'il_from' => $newid ), __METHOD__ );
3211                         $dbw->delete( 'categorylinks', array( 'cl_from' => $newid ), __METHOD__ );
3212                         $dbw->delete( 'templatelinks', array( 'tl_from' => $newid ), __METHOD__ );
3213                         $dbw->delete( 'externallinks', array( 'el_from' => $newid ), __METHOD__ );
3214                         $dbw->delete( 'langlinks', array( 'll_from' => $newid ), __METHOD__ );
3215                         $dbw->delete( 'redirect', array( 'rd_from' => $newid ), __METHOD__ );
3216                 }
3217                 // If the redirect was recently created, it may have an entry in recentchanges still
3218                 $dbw->delete( 'recentchanges',
3219                         array( 'rc_timestamp' => $rcts, 'rc_namespace' => $newns, 'rc_title' => $newdbk, 'rc_new' => 1 ),
3220                         __METHOD__
3221                 );
3222
3223                 # Save a null revision in the page's history notifying of the move
3224                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3225                 $nullRevId = $nullRevision->insertOn( $dbw );
3226
3227                 $article = new Article( $this );
3228                 wfRunHooks( 'NewRevisionFromEditComplete', array( $article, $nullRevision, $latest, $wgUser ) );
3229
3230                 # Change the name of the target page:
3231                 $dbw->update( 'page',
3232                         /* SET */ array(
3233                                 'page_touched'   => $dbw->timestamp( $now ),
3234                                 'page_namespace' => $nt->getNamespace(),
3235                                 'page_title'     => $nt->getDBkey(),
3236                                 'page_latest'    => $nullRevId,
3237                         ),
3238                         /* WHERE */ array( 'page_id' => $oldid ),
3239                         __METHOD__
3240                 );
3241                 $nt->resetArticleID( $oldid );
3242
3243                 # Recreate the redirect, this time in the other direction.
3244                 if ( $createRedirect || !$wgUser->isAllowed( 'suppressredirect' ) ) {
3245                         $mwRedir = MagicWord::get( 'redirect' );
3246                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3247                         $redirectArticle = new Article( $this );
3248                         $newid = $redirectArticle->insertOn( $dbw );
3249                         $redirectRevision = new Revision( array(
3250                                 'page'    => $newid,
3251                                 'comment' => $comment,
3252                                 'text'    => $redirectText ) );
3253                         $redirectRevision->insertOn( $dbw );
3254                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3255
3256                         wfRunHooks( 'NewRevisionFromEditComplete', array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3257
3258                         # Now, we record the link from the redirect to the new title.
3259                         # It should have no other outgoing links...
3260                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
3261                         $dbw->insert( 'pagelinks',
3262                                 array(
3263                                         'pl_from'      => $newid,
3264                                         'pl_namespace' => $nt->getNamespace(),
3265                                         'pl_title'     => $nt->getDBkey() ),
3266                                 __METHOD__ );
3267                         $redirectSuppressed = false;
3268                 } else {
3269                         $this->resetArticleID( 0 );
3270                         $redirectSuppressed = true;
3271                 }
3272
3273                 # Log the move
3274                 $log = new LogPage( 'move' );
3275                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText(), 2 => $redirectSuppressed ) );
3276
3277                 # Purge squid
3278                 if ( $wgUseSquid ) {
3279                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
3280                         $u = new SquidUpdate( $urls );
3281                         $u->doUpdate();
3282                 }
3283
3284         }
3285
3286         /**
3287          * Move page to non-existing title.
3288          *
3289          * @param $nt \type{Title} the new Title
3290          * @param $reason \type{\string} The reason for the move
3291          * @param $createRedirect \type{\bool} Whether to create a redirect from the old title to the new title
3292          *  Ignored if the user doesn't have the suppressredirect right
3293          */
3294         private function moveToNewTitle( &$nt, $reason = '', $createRedirect = true ) {
3295                 global $wgUser, $wgContLang;
3296
3297                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
3298                 if ( $reason ) {
3299                         $comment .= wfMsgExt( 'colon-separator',
3300                                 array( 'escapenoentities', 'content' ) );
3301                         $comment .= $reason;
3302                 }
3303                 # Truncate for whole multibyte characters. +5 bytes for ellipsis
3304                 $comment = $wgContLang->truncate( $comment, 250 );
3305
3306                 $newid = $nt->getArticleID();
3307                 $oldid = $this->getArticleID();
3308                 $latest = $this->getLatestRevId();
3309
3310                 $dbw = wfGetDB( DB_MASTER );
3311                 $now = $dbw->timestamp();
3312
3313                 # Save a null revision in the page's history notifying of the move
3314                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3315                 if ( !is_object( $nullRevision ) ) {
3316                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3317                 }
3318                 $nullRevId = $nullRevision->insertOn( $dbw );
3319
3320                 $article = new Article( $this );
3321                 wfRunHooks( 'NewRevisionFromEditComplete', array( $article, $nullRevision, $latest, $wgUser ) );
3322
3323                 # Rename page entry
3324                 $dbw->update( 'page',
3325                         /* SET */ array(
3326                                 'page_touched'   => $now,
3327                                 'page_namespace' => $nt->getNamespace(),
3328                                 'page_title'     => $nt->getDBkey(),
3329                                 'page_latest'    => $nullRevId,
3330                         ),
3331                         /* WHERE */ array( 'page_id' => $oldid ),
3332                         __METHOD__
3333                 );
3334                 $nt->resetArticleID( $oldid );
3335
3336                 if ( $createRedirect || !$wgUser->isAllowed( 'suppressredirect' ) ) {
3337                         # Insert redirect
3338                         $mwRedir = MagicWord::get( 'redirect' );
3339                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
3340                         $redirectArticle = new Article( $this );
3341                         $newid = $redirectArticle->insertOn( $dbw );
3342                         $redirectRevision = new Revision( array(
3343                                 'page'    => $newid,
3344                                 'comment' => $comment,
3345                                 'text'    => $redirectText ) );
3346                         $redirectRevision->insertOn( $dbw );
3347                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3348
3349                         wfRunHooks( 'NewRevisionFromEditComplete', array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3350
3351                         # Record the just-created redirect's linking to the page
3352                         $dbw->insert( 'pagelinks',
3353                                 array(
3354                                         'pl_from'      => $newid,
3355                                         'pl_namespace' => $nt->getNamespace(),
3356                                         'pl_title'     => $nt->getDBkey() ),
3357                                 __METHOD__ );
3358                         $redirectSuppressed = false;
3359                 } else {
3360                         $this->resetArticleID( 0 );
3361                         $redirectSuppressed = true;
3362                 }
3363
3364                 # Log the move
3365                 $log = new LogPage( 'move' );
3366                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText(), 2 => $redirectSuppressed ) );
3367
3368                 # Purge caches as per article creation
3369                 Article::onArticleCreate( $nt );
3370
3371                 # Purge old title from squid
3372                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
3373                 $this->purgeSquid();
3374         }
3375
3376         /**
3377          * Move this page's subpages to be subpages of $nt
3378          *
3379          * @param $nt Title Move target
3380          * @param $auth bool Whether $wgUser's permissions should be checked
3381          * @param $reason string The reason for the move
3382          * @param $createRedirect bool Whether to create redirects from the old subpages to the new ones
3383          *  Ignored if the user doesn't have the 'suppressredirect' right
3384          * @return mixed array with old page titles as keys, and strings (new page titles) or
3385          *  arrays (errors) as values, or an error array with numeric indices if no pages were moved
3386          */
3387         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3388                 global $wgMaximumMovedPages;
3389                 // Check permissions
3390                 if ( !$this->userCan( 'move-subpages' ) ) {
3391                         return array( 'cant-move-subpages' );
3392                 }
3393                 // Do the source and target namespaces support subpages?
3394                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
3395                         return array( 'namespace-nosubpages',
3396                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3397                 }
3398                 if ( !MWNamespace::hasSubpages( $nt->getNamespace() ) ) {
3399                         return array( 'namespace-nosubpages',
3400                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3401                 }
3402
3403                 $subpages = $this->getSubpages( $wgMaximumMovedPages + 1 );
3404                 $retval = array();
3405                 $count = 0;
3406                 foreach ( $subpages as $oldSubpage ) {
3407                         $count++;
3408                         if ( $count > $wgMaximumMovedPages ) {
3409                                 $retval[$oldSubpage->getPrefixedTitle()] =
3410                                                 array( 'movepage-max-pages',
3411                                                         $wgMaximumMovedPages );
3412                                 break;
3413                         }
3414
3415                         // We don't know whether this function was called before
3416                         // or after moving the root page, so check both
3417                         // $this and $nt
3418                         if ( $oldSubpage->getArticleId() == $this->getArticleId() ||
3419                                         $oldSubpage->getArticleID() == $nt->getArticleId() )
3420                         {
3421                                 // When moving a page to a subpage of itself,
3422                                 // don't move it twice
3423                                 continue;
3424                         }
3425                         $newPageName = preg_replace(
3426                                         '#^' . preg_quote( $this->getDBkey(), '#' ) . '#',
3427                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3428                                         $oldSubpage->getDBkey() );
3429                         if ( $oldSubpage->isTalkPage() ) {
3430                                 $newNs = $nt->getTalkPage()->getNamespace();
3431                         } else {
3432                                 $newNs = $nt->getSubjectPage()->getNamespace();
3433                         }
3434                         # Bug 14385: we need makeTitleSafe because the new page names may
3435                         # be longer than 255 characters.
3436                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3437
3438                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3439                         if ( $success === true ) {
3440                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3441                         } else {
3442                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3443                         }
3444                 }
3445                 return $retval;
3446         }
3447
3448         /**
3449          * Checks if this page is just a one-rev redirect.
3450          * Adds lock, so don't use just for light purposes.
3451          *
3452          * @return \type{\bool}
3453          */
3454         public function isSingleRevRedirect() {
3455                 $dbw = wfGetDB( DB_MASTER );
3456                 # Is it a redirect?
3457                 $row = $dbw->selectRow( 'page',
3458                         array( 'page_is_redirect', 'page_latest', 'page_id' ),
3459                         $this->pageCond(),
3460                         __METHOD__,
3461                         array( 'FOR UPDATE' )
3462                 );
3463                 # Cache some fields we may want
3464                 $this->mArticleID = $row ? intval( $row->page_id ) : 0;
3465                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3466                 $this->mLatestID = $row ? intval( $row->page_latest ) : false;
3467                 if ( !$this->mRedirect ) {
3468                         return false;
3469                 }
3470                 # Does the article have a history?
3471                 $row = $dbw->selectField( array( 'page', 'revision' ),
3472                         'rev_id',
3473                         array( 'page_namespace' => $this->getNamespace(),
3474                                 'page_title' => $this->getDBkey(),
3475                                 'page_id=rev_page',
3476                                 'page_latest != rev_id'
3477                         ),
3478                         __METHOD__,
3479                         array( 'FOR UPDATE' )
3480                 );
3481                 # Return true if there was no history
3482                 return ( $row === false );
3483         }
3484
3485         /**
3486          * Checks if $this can be moved to a given Title
3487          * - Selects for update, so don't call it unless you mean business
3488          *
3489          * @param $nt \type{Title} the new title to check
3490          * @return \type{\bool} TRUE or FALSE
3491          */
3492         public function isValidMoveTarget( $nt ) {
3493                 # Is it an existing file?
3494                 if ( $nt->getNamespace() == NS_FILE ) {
3495                         $file = wfLocalFile( $nt );
3496                         if ( $file->exists() ) {
3497                                 wfDebug( __METHOD__ . ": file exists\n" );
3498                                 return false;
3499                         }
3500                 }
3501                 # Is it a redirect with no history?
3502                 if ( !$nt->isSingleRevRedirect() ) {
3503                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3504                         return false;
3505                 }
3506                 # Get the article text
3507                 $rev = Revision::newFromTitle( $nt );
3508                 $text = $rev->getText();
3509                 # Does the redirect point to the source?
3510                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3511                 $m = array();
3512                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
3513                         $redirTitle = Title::newFromText( $m[1] );
3514                         if ( !is_object( $redirTitle ) ||
3515                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3516                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
3517                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3518                                 return false;
3519                         }
3520                 } else {
3521                         # Fail safe
3522                         wfDebug( __METHOD__ . ": failsafe\n" );
3523                         return false;
3524                 }
3525                 return true;
3526         }
3527
3528         /**
3529          * Can this title be added to a user's watchlist?
3530          *
3531          * @return \type{\bool} TRUE or FALSE
3532          */
3533         public function isWatchable() {
3534                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
3535         }
3536
3537         /**
3538          * Get categories to which this Title belongs and return an array of
3539          * categories' names.
3540          *
3541          * @return \type{\array} array an array of parents in the form:
3542          *      $parent => $currentarticle
3543          */
3544         public function getParentCategories() {
3545                 global $wgContLang;
3546
3547                 $titlekey = $this->getArticleId();
3548                 $dbr = wfGetDB( DB_SLAVE );
3549                 $categorylinks = $dbr->tableName( 'categorylinks' );
3550
3551                 # NEW SQL
3552                 $sql = "SELECT * FROM $categorylinks"
3553                      . " WHERE cl_from='$titlekey'"
3554                          . " AND cl_from <> '0'"
3555                          . " ORDER BY cl_sortkey";
3556
3557                 $res = $dbr->query( $sql );
3558                 $data = array();
3559
3560                 if ( $dbr->numRows( $res ) > 0 ) {
3561                         foreach ( $res as $row ) {
3562                                 // $data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
3563                                 $data[$wgContLang->getNSText( NS_CATEGORY ) . ':' . $row->cl_to] = $this->getFullText();
3564                         }
3565                 }
3566                 return $data;
3567         }
3568
3569         /**
3570          * Get a tree of parent categories
3571          *
3572          * @param $children \type{\array} an array with the children in the keys, to check for circular refs
3573          * @return \type{\array} Tree of parent categories
3574          */
3575         public function getParentCategoryTree( $children = array() ) {
3576                 $stack = array();
3577                 $parents = $this->getParentCategories();
3578
3579                 if ( $parents ) {
3580                         foreach ( $parents as $parent => $current ) {
3581                                 if ( array_key_exists( $parent, $children ) ) {
3582                                         # Circular reference
3583                                         $stack[$parent] = array();
3584                                 } else {
3585                                         $nt = Title::newFromText( $parent );
3586                                         if ( $nt ) {
3587                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array( $parent => 1 ) );
3588                                         }
3589                                 }
3590                         }
3591                 }
3592
3593                 return $stack;
3594         }
3595
3596
3597         /**
3598          * Get an associative array for selecting this title from
3599          * the "page" table
3600          *
3601          * @return \type{\array} Selection array
3602          */
3603         public function pageCond() {
3604                 if ( $this->mArticleID > 0 ) {
3605                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
3606                         return array( 'page_id' => $this->mArticleID );
3607                 } else {
3608                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
3609                 }
3610         }
3611
3612         /**
3613          * Get the revision ID of the previous revision
3614          *
3615          * @param $revId \type{\int} Revision ID. Get the revision that was before this one.
3616          * @param $flags \type{\int} Title::GAID_FOR_UPDATE
3617          * @return \twotypes{\int,\bool} Old revision ID, or FALSE if none exists
3618          */
3619         public function getPreviousRevisionID( $revId, $flags = 0 ) {
3620                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3621                 return $db->selectField( 'revision', 'rev_id',
3622                         array(
3623                                 'rev_page' => $this->getArticleId( $flags ),
3624                                 'rev_id < ' . intval( $revId )
3625                         ),
3626                         __METHOD__,
3627                         array( 'ORDER BY' => 'rev_id DESC' )
3628                 );
3629         }
3630
3631         /**
3632          * Get the revision ID of the next revision
3633          *
3634          * @param $revId \type{\int} Revision ID. Get the revision that was after this one.
3635          * @param $flags \type{\int} Title::GAID_FOR_UPDATE
3636          * @return \twotypes{\int,\bool} Next revision ID, or FALSE if none exists
3637          */
3638         public function getNextRevisionID( $revId, $flags = 0 ) {
3639                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3640                 return $db->selectField( 'revision', 'rev_id',
3641                         array(
3642                                 'rev_page' => $this->getArticleId( $flags ),
3643                                 'rev_id > ' . intval( $revId )
3644                         ),
3645                         __METHOD__,
3646                         array( 'ORDER BY' => 'rev_id' )
3647                 );
3648         }
3649
3650         /**
3651          * Get the first revision of the page
3652          *
3653          * @param $flags \type{\int} Title::GAID_FOR_UPDATE
3654          * @return Revision (or NULL if page doesn't exist)
3655          */
3656         public function getFirstRevision( $flags = 0 ) {
3657                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3658                 $pageId = $this->getArticleId( $flags );
3659                 if ( !$pageId ) {
3660                         return null;
3661                 }
3662                 $row = $db->selectRow( 'revision', '*',
3663                         array( 'rev_page' => $pageId ),
3664                         __METHOD__,
3665                         array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
3666                 );
3667                 if ( !$row ) {
3668                         return null;
3669                 } else {
3670                         return new Revision( $row );
3671                 }
3672         }
3673
3674         /**
3675          * Check if this is a new page
3676          *
3677          * @return bool
3678          */
3679         public function isNewPage() {
3680                 $dbr = wfGetDB( DB_SLAVE );
3681                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
3682         }
3683
3684         /**
3685          * Get the oldest revision timestamp of this page
3686          *
3687          * @return String: MW timestamp
3688          */
3689         public function getEarliestRevTime() {
3690                 $dbr = wfGetDB( DB_SLAVE );
3691                 if ( $this->exists() ) {
3692                         $min = $dbr->selectField( 'revision',
3693                                 'MIN(rev_timestamp)',
3694                                 array( 'rev_page' => $this->getArticleId() ),
3695                                 __METHOD__ );
3696                         return wfTimestampOrNull( TS_MW, $min );
3697                 }
3698                 return null;
3699         }
3700
3701         /**
3702          * Get the number of revisions between the given revision IDs.
3703          * Used for diffs and other things that really need it.
3704          *
3705          * @param $old \type{\int} Revision ID.
3706          * @param $new \type{\int} Revision ID.
3707          * @return \type{\int} Number of revisions between these IDs.
3708          */
3709         public function countRevisionsBetween( $old, $new ) {
3710                 $dbr = wfGetDB( DB_SLAVE );
3711                 return (int)$dbr->selectField( 'revision', 'count(*)',
3712                         'rev_page = ' . intval( $this->getArticleId() ) .
3713                         ' AND rev_id > ' . intval( $old ) .
3714                         ' AND rev_id < ' . intval( $new ),
3715                         __METHOD__
3716                 );
3717         }
3718
3719         /**
3720          * Compare with another title.
3721          *
3722          * @param $title \type{Title}
3723          * @return \type{\bool} TRUE or FALSE
3724          */
3725         public function equals( Title $title ) {
3726                 // Note: === is necessary for proper matching of number-like titles.
3727                 return $this->getInterwiki() === $title->getInterwiki()
3728                         && $this->getNamespace() == $title->getNamespace()
3729                         && $this->getDBkey() === $title->getDBkey();
3730         }
3731
3732         /**
3733          * Callback for usort() to do title sorts by (namespace, title)
3734          *
3735          * @return Integer: result of string comparison, or namespace comparison
3736          */
3737         public static function compare( $a, $b ) {
3738                 if ( $a->getNamespace() == $b->getNamespace() ) {
3739                         return strcmp( $a->getText(), $b->getText() );
3740                 } else {
3741                         return $a->getNamespace() - $b->getNamespace();
3742                 }
3743         }
3744
3745         /**
3746          * Return a string representation of this title
3747          *
3748          * @return \type{\string} String representation of this title
3749          */
3750         public function __toString() {
3751                 return $this->getPrefixedText();
3752         }
3753
3754         /**
3755          * Check if page exists.  For historical reasons, this function simply
3756          * checks for the existence of the title in the page table, and will
3757          * thus return false for interwiki links, special pages and the like.
3758          * If you want to know if a title can be meaningfully viewed, you should
3759          * probably call the isKnown() method instead.
3760          *
3761          * @return \type{\bool}
3762          */
3763         public function exists() {
3764                 return $this->getArticleId() != 0;
3765         }
3766
3767         /**
3768          * Should links to this title be shown as potentially viewable (i.e. as
3769          * "bluelinks"), even if there's no record by this title in the page
3770          * table?
3771          *
3772          * This function is semi-deprecated for public use, as well as somewhat
3773          * misleadingly named.  You probably just want to call isKnown(), which
3774          * calls this function internally.
3775          *
3776          * (ISSUE: Most of these checks are cheap, but the file existence check
3777          * can potentially be quite expensive.  Including it here fixes a lot of
3778          * existing code, but we might want to add an optional parameter to skip
3779          * it and any other expensive checks.)
3780          *
3781          * @return \type{\bool}
3782          */
3783         public function isAlwaysKnown() {
3784                 if ( $this->mInterwiki != '' ) {
3785                         return true;  // any interwiki link might be viewable, for all we know
3786                 }
3787                 switch( $this->mNamespace ) {
3788                         case NS_MEDIA:
3789                         case NS_FILE:
3790                                 return (bool)wfFindFile( $this );  // file exists, possibly in a foreign repo
3791                         case NS_SPECIAL:
3792                                 return SpecialPage::exists( $this->getDBkey() );  // valid special page
3793                         case NS_MAIN:
3794                                 return $this->mDbkeyform == '';  // selflink, possibly with fragment
3795                         case NS_MEDIAWIKI:
3796                                 // If the page is form Mediawiki:message/lang, calling wfMsgWeirdKey causes
3797                                 // the full l10n of that language to be loaded. That takes much memory and
3798                                 // isn't needed. So we strip the language part away.
3799                                 list( $basename, /* rest */ ) = explode( '/', $this->mDbkeyform, 2 );
3800                                 return (bool)wfMsgWeirdKey( $basename );  // known system message
3801                         default:
3802                                 return false;
3803                 }
3804         }
3805
3806         /**
3807          * Does this title refer to a page that can (or might) be meaningfully
3808          * viewed?  In particular, this function may be used to determine if
3809          * links to the title should be rendered as "bluelinks" (as opposed to
3810          * "redlinks" to non-existent pages).
3811          *
3812          * @return \type{\bool}
3813          */
3814         public function isKnown() {
3815                 return $this->isAlwaysKnown() || $this->exists();
3816         }
3817
3818         /**
3819          * Does this page have source text?
3820          *
3821          * @return Boolean
3822          */
3823         public function hasSourceText() {
3824                 if ( $this->exists() ) {
3825                         return true;
3826                 }
3827
3828                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
3829                         // If the page doesn't exist but is a known system message, default
3830                         // message content will be displayed, same for language subpages
3831                         // Also, if the page is form Mediawiki:message/lang, calling wfMsgWeirdKey
3832                         // causes the full l10n of that language to be loaded. That takes much
3833                         // memory and isn't needed. So we strip the language part away.
3834                         list( $basename, /* rest */ ) = explode( '/', $this->mDbkeyform, 2 );
3835                         return (bool)wfMsgWeirdKey( $basename );
3836                 }
3837
3838                 return false;
3839         }
3840
3841         /**
3842          * Is this in a namespace that allows actual pages?
3843          *
3844          * @return \type{\bool}
3845          * @internal note -- uses hardcoded namespace index instead of constants
3846          */
3847         public function canExist() {
3848                 return $this->mNamespace >= 0 && $this->mNamespace != NS_MEDIA;
3849         }
3850
3851         /**
3852          * Update page_touched timestamps and send squid purge messages for
3853          * pages linking to this title. May be sent to the job queue depending
3854          * on the number of links. Typically called on create and delete.
3855          */
3856         public function touchLinks() {
3857                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
3858                 $u->doUpdate();
3859
3860                 if ( $this->getNamespace() == NS_CATEGORY ) {
3861                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
3862                         $u->doUpdate();
3863                 }
3864         }
3865
3866         /**
3867          * Get the last touched timestamp
3868          *
3869          * @param $db DatabaseBase: optional db
3870          * @return \type{\string} Last touched timestamp
3871          */
3872         public function getTouched( $db = null ) {
3873                 $db = isset( $db ) ? $db : wfGetDB( DB_SLAVE );
3874                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
3875                 return $touched;
3876         }
3877
3878         /**
3879          * Get the timestamp when this page was updated since the user last saw it.
3880          *
3881          * @param $user User
3882          * @return Mixed: string/null
3883          */
3884         public function getNotificationTimestamp( $user = null ) {
3885                 global $wgUser, $wgShowUpdatedMarker;
3886                 // Assume current user if none given
3887                 if ( !$user ) {
3888                         $user = $wgUser;
3889                 }
3890                 // Check cache first
3891                 $uid = $user->getId();
3892                 if ( isset( $this->mNotificationTimestamp[$uid] ) ) {
3893                         return $this->mNotificationTimestamp[$uid];
3894                 }
3895                 if ( !$uid || !$wgShowUpdatedMarker ) {
3896                         return $this->mNotificationTimestamp[$uid] = false;
3897                 }
3898                 // Don't cache too much!
3899                 if ( count( $this->mNotificationTimestamp ) >= self::CACHE_MAX ) {
3900                         $this->mNotificationTimestamp = array();
3901                 }
3902                 $dbr = wfGetDB( DB_SLAVE );
3903                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
3904                         'wl_notificationtimestamp',
3905                         array( 'wl_namespace' => $this->getNamespace(),
3906                                 'wl_title' => $this->getDBkey(),
3907                                 'wl_user' => $user->getId()
3908                         ),
3909                         __METHOD__
3910                 );
3911                 return $this->mNotificationTimestamp[$uid];
3912         }
3913
3914         /**
3915          * Get the trackback URL for this page
3916          *
3917          * @return \type{\string} Trackback URL
3918          */
3919         public function trackbackURL() {
3920                 global $wgScriptPath, $wgServer, $wgScriptExtension;
3921
3922                 return "$wgServer$wgScriptPath/trackback$wgScriptExtension?article="
3923                         . htmlspecialchars( urlencode( $this->getPrefixedDBkey() ) );
3924         }
3925
3926         /**
3927          * Get the trackback RDF for this page
3928          *
3929          * @return \type{\string} Trackback RDF
3930          */
3931         public function trackbackRDF() {
3932                 $url = htmlspecialchars( $this->getFullURL() );
3933                 $title = htmlspecialchars( $this->getText() );
3934                 $tburl = $this->trackbackURL();
3935
3936                 // Autodiscovery RDF is placed in comments so HTML validator
3937                 // won't barf. This is a rather icky workaround, but seems
3938                 // frequently used by this kind of RDF thingy.
3939                 //
3940                 // Spec: http://www.sixapart.com/pronet/docs/trackback_spec
3941                 return "<!--
3942 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
3943          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
3944          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
3945 <rdf:Description
3946    rdf:about=\"$url\"
3947    dc:identifier=\"$url\"
3948    dc:title=\"$title\"
3949    trackback:ping=\"$tburl\" />
3950 </rdf:RDF>
3951 -->";
3952         }
3953
3954         /**
3955          * Generate strings used for xml 'id' names in monobook tabs
3956          *
3957          * @param $prepend string defaults to 'nstab-'
3958          * @return \type{\string} XML 'id' name
3959          */
3960         public function getNamespaceKey( $prepend = 'nstab-' ) {
3961                 global $wgContLang;
3962                 // Gets the subject namespace if this title
3963                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
3964                 // Checks if cononical namespace name exists for namespace
3965                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
3966                         // Uses canonical namespace name
3967                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
3968                 } else {
3969                         // Uses text of namespace
3970                         $namespaceKey = $this->getSubjectNsText();
3971                 }
3972                 // Makes namespace key lowercase
3973                 $namespaceKey = $wgContLang->lc( $namespaceKey );
3974                 // Uses main
3975                 if ( $namespaceKey == '' ) {
3976                         $namespaceKey = 'main';
3977                 }
3978                 // Changes file to image for backwards compatibility
3979                 if ( $namespaceKey == 'file' ) {
3980                         $namespaceKey = 'image';
3981                 }
3982                 return $prepend . $namespaceKey;
3983         }
3984
3985         /**
3986          * Returns true if this is a special page.
3987          *
3988          * @return boolean
3989          */
3990         public function isSpecialPage() {
3991                 return $this->getNamespace() == NS_SPECIAL;
3992         }
3993
3994         /**
3995          * Returns true if this title resolves to the named special page
3996          *
3997          * @param $name \type{\string} The special page name
3998          * @return boolean
3999          */
4000         public function isSpecial( $name ) {
4001                 if ( $this->getNamespace() == NS_SPECIAL ) {
4002                         list( $thisName, /* $subpage */ ) = SpecialPage::resolveAliasWithSubpage( $this->getDBkey() );
4003                         if ( $name == $thisName ) {
4004                                 return true;
4005                         }
4006                 }
4007                 return false;
4008         }
4009
4010         /**
4011          * If the Title refers to a special page alias which is not the local default,
4012          *
4013          * @return \type{Title} A new Title which points to the local default.
4014          *         Otherwise, returns $this.
4015          */
4016         public function fixSpecialName() {
4017                 if ( $this->getNamespace() == NS_SPECIAL ) {
4018                         $canonicalName = SpecialPage::resolveAlias( $this->mDbkeyform );
4019                         if ( $canonicalName ) {
4020                                 $localName = SpecialPage::getLocalNameFor( $canonicalName );
4021                                 if ( $localName != $this->mDbkeyform ) {
4022                                         return Title::makeTitle( NS_SPECIAL, $localName );
4023                                 }
4024                         }
4025                 }
4026                 return $this;
4027         }
4028
4029         /**
4030          * Is this Title in a namespace which contains content?
4031          * In other words, is this a content page, for the purposes of calculating
4032          * statistics, etc?
4033          *
4034          * @return \type{\bool}
4035          */
4036         public function isContentPage() {
4037                 return MWNamespace::isContent( $this->getNamespace() );
4038         }
4039
4040         /**
4041          * Get all extant redirects to this Title
4042          *
4043          * @param $ns \twotypes{\int,\null} Single namespace to consider;
4044          *            NULL to consider all namespaces
4045          * @return \type{\arrayof{Title}} Redirects to this title
4046          */
4047         public function getRedirectsHere( $ns = null ) {
4048                 $redirs = array();
4049
4050                 $dbr = wfGetDB( DB_SLAVE );
4051                 $where = array(
4052                         'rd_namespace' => $this->getNamespace(),
4053                         'rd_title' => $this->getDBkey(),
4054                         'rd_from = page_id'
4055                 );
4056                 if ( !is_null( $ns ) ) {
4057                         $where['page_namespace'] = $ns;
4058                 }
4059
4060                 $res = $dbr->select(
4061                         array( 'redirect', 'page' ),
4062                         array( 'page_namespace', 'page_title' ),
4063                         $where,
4064                         __METHOD__
4065                 );
4066
4067                 foreach ( $res as $row ) {
4068                         $redirs[] = self::newFromRow( $row );
4069                 }
4070                 return $redirs;
4071         }
4072
4073         /**
4074          * Check if this Title is a valid redirect target
4075          *
4076          * @return \type{\bool}
4077          */
4078         public function isValidRedirectTarget() {
4079                 global $wgInvalidRedirectTargets;
4080
4081                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
4082                 if ( $this->isSpecial( 'Userlogout' ) ) {
4083                         return false;
4084                 }
4085
4086                 foreach ( $wgInvalidRedirectTargets as $target ) {
4087                         if ( $this->isSpecial( $target ) ) {
4088                                 return false;
4089                         }
4090                 }
4091
4092                 return true;
4093         }
4094
4095         /**
4096          * Get a backlink cache object
4097          *
4098          * @return object BacklinkCache
4099          */
4100         function getBacklinkCache() {
4101                 if ( is_null( $this->mBacklinkCache ) ) {
4102                         $this->mBacklinkCache = new BacklinkCache( $this );
4103                 }
4104                 return $this->mBacklinkCache;
4105         }
4106
4107         /**
4108          * Whether the magic words __INDEX__ and __NOINDEX__ function for
4109          * this page.
4110          *
4111          * @return Boolean
4112          */
4113         public function canUseNoindex() {
4114                 global $wgContentNamespaces, $wgExemptFromUserRobotsControl;
4115
4116                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
4117                         ? $wgContentNamespaces
4118                         : $wgExemptFromUserRobotsControl;
4119
4120                 return !in_array( $this->mNamespace, $bannedNamespaces );
4121
4122         }
4123
4124         /**
4125          * Returns restriction types for the current Title
4126          *
4127          * @return array applicable restriction types
4128          */
4129         public function getRestrictionTypes() {
4130                 global $wgRestrictionTypes;
4131                 $types = $this->exists() ? $wgRestrictionTypes : array( 'create' );
4132
4133                 if ( $this->getNamespace() == NS_FILE ) {
4134                         $types[] = 'upload';
4135                 }
4136
4137                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
4138
4139                 return $types;
4140         }
4141
4142         /**
4143          * Returns the raw sort key to be used for categories, with the specified
4144          * prefix.  This will be fed to Language::convertToSortkey() to get a
4145          * binary sortkey that can be used for actual sorting.
4146          *
4147          * @param $prefix string The prefix to be used, specified using
4148          *   {{defaultsort:}} or like [[Category:Foo|prefix]].  Empty for no
4149          *   prefix.
4150          * @return string
4151          */
4152         public function getCategorySortkey( $prefix = '' ) {
4153                 $unprefixed = $this->getText();
4154                 if ( $prefix !== '' ) {
4155                         # Separate with a null byte, so the unprefixed part is only used as
4156                         # a tiebreaker when two pages have the exact same prefix -- null
4157                         # sorts before everything else (hopefully).
4158                         return "$prefix\0$unprefixed";
4159                 }
4160                 return $unprefixed;
4161         }
4162 }