includes/Title.php

   1 <?php
   2 /**
   3  * Representation a title within %MediaWiki.
   4  *
   5  * See title.txt
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  20  * http://www.gnu.org/copyleft/gpl.html
  21  *
  22  * @file
  23  */
  24
  25 /**
  26  * Represents a title within MediaWiki.
  27  * Optionally may contain an interwiki designation or namespace.
  28  * @note This class can fetch various kinds of data from the database;
  29  *       however, it does so inefficiently.
  30  *
  31  * @internal documentation reviewed 15 Mar 2010
  32  */
  33 class Title {
  34         /** @name Static cache variables */
  35         // @{
  36         static private $titleCache = array();
  37         // @}
  38
  39         /**
  40          * Title::newFromText maintains a cache to avoid expensive re-normalization of
  41          * commonly used titles. On a batch operation this can become a memory leak
  42          * if not bounded. After hitting this many titles reset the cache.
  43          */
  44         const CACHE_MAX = 1000;
  45
  46         /**
  47          * Used to be GAID_FOR_UPDATE define. Used with getArticleID() and friends
  48          * to use the master DB
  49          */
  50         const GAID_FOR_UPDATE = 1;
  51
  52         /**
  53          * @name Private member variables
  54          * Please use the accessor functions instead.
  55          * @private
  56          */
  57         // @{
  58
  59         var $mTextform = '';              // /< Text form (spaces not underscores) of the main part
  60         var $mUrlform = '';               // /< URL-encoded form of the main part
  61         var $mDbkeyform = '';             // /< Main part with underscores
  62         var $mUserCaseDBKey;              // /< DB key with the initial letter in the case specified by the user
  63         var $mNamespace = NS_MAIN;        // /< Namespace index, i.e. one of the NS_xxxx constants
  64         var $mInterwiki = '';             // /< Interwiki prefix (or null string)
  65         var $mFragment;                   // /< Title fragment (i.e. the bit after the #)
  66         var $mArticleID = -1;             // /< Article ID, fetched from the link cache on demand
  67         var $mLatestID = false;           // /< ID of most recent revision
  68         var $mContentModel = false;       // /< ID of the page's content model, i.e. one of the CONTENT_MODEL_XXX constants
  69         private $mEstimateRevisions;      // /< Estimated number of revisions; null of not loaded
  70         var $mRestrictions = array();     // /< Array of groups allowed to edit this article
  71         var $mOldRestrictions = false;
  72         var $mCascadeRestriction;         ///< Cascade restrictions on this page to included templates and images?
  73         var $mCascadingRestrictions;      // Caching the results of getCascadeProtectionSources
  74         var $mRestrictionsExpiry = array(); ///< When do the restrictions on this page expire?
  75         var $mHasCascadingRestrictions;   ///< Are cascading restrictions in effect on this page?
  76         var $mCascadeSources;             ///< Where are the cascading restrictions coming from on this page?
  77         var $mRestrictionsLoaded = false; ///< Boolean for initialisation on demand
  78         var $mPrefixedText;               ///< Text form including namespace/interwiki, initialised on demand
  79         var $mTitleProtection;            ///< Cached value for getTitleProtection (create protection)
  80         # Don't change the following default, NS_MAIN is hardcoded in several
  81         # places.  See bug 696.
  82         var $mDefaultNamespace = NS_MAIN; // /< Namespace index when there is no namespace
  83                                                                           # Zero except in {{transclusion}} tags
  84         var $mWatched = null;             // /< Is $wgUser watching this page? null if unfilled, accessed through userIsWatching()
  85         var $mLength = -1;                // /< The page length, 0 for special pages
  86         var $mRedirect = null;            // /< Is the article at this title a redirect?
  87         var $mNotificationTimestamp = array(); // /< Associative array of user ID -> timestamp/false
  88         var $mHasSubpage;                 // /< Whether a page has any subpages
  89         // @}
  90
  91
  92         /**
  93          * Constructor
  94          */
  95         /*protected*/ function __construct() { }
  96
  97         /**
  98          * Create a new Title from a prefixed DB key
  99          *
 100          * @param $key String the database key, which has underscores
 101          *      instead of spaces, possibly including namespace and
 102          *      interwiki prefixes
 103          * @return Title, or NULL on an error
 104          */
 105         public static function newFromDBkey( $key ) {
 106                 $t = new Title();
 107                 $t->mDbkeyform = $key;
 108                 if ( $t->secureAndSplit() ) {
 109                         return $t;
 110                 } else {
 111                         return null;
 112                 }
 113         }
 114
 115         /**
 116          * Create a new Title from text, such as what one would find in a link. De-
 117          * codes any HTML entities in the text.
 118          *
 119          * @param $text String the link text; spaces, prefixes, and an
 120          *   initial ':' indicating the main namespace are accepted.
 121          * @param $defaultNamespace Int the namespace to use if none is speci-
 122          *   fied by a prefix.  If you want to force a specific namespace even if
 123          *   $text might begin with a namespace prefix, use makeTitle() or
 124          *   makeTitleSafe().
 125          * @throws MWException
 126          * @return Title|null - Title or null on an error.
 127          */
 128         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 129                 if ( is_object( $text ) ) {
 130                         throw new MWException( 'Title::newFromText given an object' );
 131                 }
 132
 133                 /**
 134                  * Wiki pages often contain multiple links to the same page.
 135                  * Title normalization and parsing can become expensive on
 136                  * pages with many links, so we can save a little time by
 137                  * caching them.
 138                  *
 139                  * In theory these are value objects and won't get changed...
 140                  */
 141                 if ( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 142                         return Title::$titleCache[$text];
 143                 }
 144
 145                 # Convert things like &eacute; &#257; or &#x3017; into normalized (bug 14952) text
 146                 $filteredText = Sanitizer::decodeCharReferencesAndNormalize( $text );
 147
 148                 $t = new Title();
 149                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 150                 $t->mDefaultNamespace = $defaultNamespace;
 151
 152                 static $cachedcount = 0;
 153                 if ( $t->secureAndSplit() ) {
 154                         if ( $defaultNamespace == NS_MAIN ) {
 155                                 if ( $cachedcount >= self::CACHE_MAX ) {
 156                                         # Avoid memory leaks on mass operations...
 157                                         Title::$titleCache = array();
 158                                         $cachedcount = 0;
 159                                 }
 160                                 $cachedcount++;
 161                                 Title::$titleCache[$text] =& $t;
 162                         }
 163                         return $t;
 164                 } else {
 165                         $ret = null;
 166                         return $ret;
 167                 }
 168         }
 169
 170         /**
 171          * THIS IS NOT THE FUNCTION YOU WANT. Use Title::newFromText().
 172          *
 173          * Example of wrong and broken code:
 174          * $title = Title::newFromURL( $wgRequest->getVal( 'title' ) );
 175          *
 176          * Example of right code:
 177          * $title = Title::newFromText( $wgRequest->getVal( 'title' ) );
 178          *
 179          * Create a new Title from URL-encoded text. Ensures that
 180          * the given title's length does not exceed the maximum.
 181          *
 182          * @param $url String the title, as might be taken from a URL
 183          * @return Title the new object, or NULL on an error
 184          */
 185         public static function newFromURL( $url ) {
 186                 $t = new Title();
 187
 188                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 189                 # but some URLs used it as a space replacement and they still come
 190                 # from some external search tools.
 191                 if ( strpos( self::legalChars(), '+' ) === false ) {
 192                         $url = str_replace( '+', ' ', $url );
 193                 }
 194
 195                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 196                 if ( $t->secureAndSplit() ) {
 197                         return $t;
 198                 } else {
 199                         return null;
 200                 }
 201         }
 202
 203         /**
 204          * Returns a list of fields that are to be selected for initializing Title objects or LinkCache entries.
 205          * Uses $wgContentHandlerUseDB to determine whether to include page_content_model.
 206          *
 207          * @return array
 208          */
 209         protected static function getSelectFields() {
 210                 global $wgContentHandlerUseDB;
 211
 212                 $fields = array(
 213                         'page_namespace', 'page_title', 'page_id',
 214                         'page_len', 'page_is_redirect', 'page_latest',
 215                 );
 216
 217                 if ( $wgContentHandlerUseDB ) {
 218                         $fields[] = 'page_content_model';
 219                 }
 220
 221                 return $fields;
 222         }
 223
 224         /**
 225          * Create a new Title from an article ID
 226          *
 227          * @param $id Int the page_id corresponding to the Title to create
 228          * @param $flags Int use Title::GAID_FOR_UPDATE to use master
 229          * @return Title the new object, or NULL on an error
 230          */
 231         public static function newFromID( $id, $flags = 0 ) {
 232                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
 233                 $row = $db->selectRow(
 234                         'page',
 235                         self::getSelectFields(),
 236                         array( 'page_id' => $id ),
 237                         __METHOD__
 238                 );
 239                 if ( $row !== false ) {
 240                         $title = Title::newFromRow( $row );
 241                 } else {
 242                         $title = null;
 243                 }
 244                 return $title;
 245         }
 246
 247         /**
 248          * Make an array of titles from an array of IDs
 249          *
 250          * @param $ids Array of Int Array of IDs
 251          * @return Array of Titles
 252          */
 253         public static function newFromIDs( $ids ) {
 254                 if ( !count( $ids ) ) {
 255                         return array();
 256                 }
 257                 $dbr = wfGetDB( DB_SLAVE );
 258
 259                 $res = $dbr->select(
 260                         'page',
 261                         self::getSelectFields(),
 262                         array( 'page_id' => $ids ),
 263                         __METHOD__
 264                 );
 265
 266                 $titles = array();
 267                 foreach ( $res as $row ) {
 268                         $titles[] = Title::newFromRow( $row );
 269                 }
 270                 return $titles;
 271         }
 272
 273         /**
 274          * Make a Title object from a DB row
 275          *
 276          * @param $row Object database row (needs at least page_title,page_namespace)
 277          * @return Title corresponding Title
 278          */
 279         public static function newFromRow( $row ) {
 280                 $t = self::makeTitle( $row->page_namespace, $row->page_title );
 281                 $t->loadFromRow( $row );
 282                 return $t;
 283         }
 284
 285         /**
 286          * Load Title object fields from a DB row.
 287          * If false is given, the title will be treated as non-existing.
 288          *
 289          * @param $row Object|bool database row
 290          */
 291         public function loadFromRow( $row ) {
 292                 if ( $row ) { // page found
 293                         if ( isset( $row->page_id ) )
 294                                 $this->mArticleID = (int)$row->page_id;
 295                         if ( isset( $row->page_len ) )
 296                                 $this->mLength = (int)$row->page_len;
 297                         if ( isset( $row->page_is_redirect ) )
 298                                 $this->mRedirect = (bool)$row->page_is_redirect;
 299                         if ( isset( $row->page_latest ) )
 300                                 $this->mLatestID = (int)$row->page_latest;
 301                         if ( isset( $row->page_content_model ) )
 302                                 $this->mContentModel = strval( $row->page_content_model );
 303                         else
 304                                 $this->mContentModel = false; # initialized lazily in getContentModel()
 305                 } else { // page not found
 306                         $this->mArticleID = 0;
 307                         $this->mLength = 0;
 308                         $this->mRedirect = false;
 309                         $this->mLatestID = 0;
 310                         $this->mContentModel = false; # initialized lazily in getContentModel()
 311                 }
 312         }
 313
 314         /**
 315          * Create a new Title from a namespace index and a DB key.
 316          * It's assumed that $ns and $title are *valid*, for instance when
 317          * they came directly from the database or a special page name.
 318          * For convenience, spaces are converted to underscores so that
 319          * eg user_text fields can be used directly.
 320          *
 321          * @param $ns Int the namespace of the article
 322          * @param $title String the unprefixed database key form
 323          * @param $fragment String the link fragment (after the "#")
 324          * @param $interwiki String the interwiki prefix
 325          * @return Title the new object
 326          */
 327         public static function &makeTitle( $ns, $title, $fragment = '', $interwiki = '' ) {
 328                 $t = new Title();
 329                 $t->mInterwiki = $interwiki;
 330                 $t->mFragment = $fragment;
 331                 $t->mNamespace = $ns = intval( $ns );
 332                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 333                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 334                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 335                 $t->mTextform = str_replace( '_', ' ', $title );
 336                 $t->mContentModel = false; # initialized lazily in getContentModel()
 337                 return $t;
 338         }
 339
 340         /**
 341          * Create a new Title from a namespace index and a DB key.
 342          * The parameters will be checked for validity, which is a bit slower
 343          * than makeTitle() but safer for user-provided data.
 344          *
 345          * @param $ns Int the namespace of the article
 346          * @param $title String database key form
 347          * @param $fragment String the link fragment (after the "#")
 348          * @param $interwiki String interwiki prefix
 349          * @return Title the new object, or NULL on an error
 350          */
 351         public static function makeTitleSafe( $ns, $title, $fragment = '', $interwiki = '' ) {
 352                 if ( !MWNamespace::exists( $ns ) ) {
 353                         return null;
 354                 }
 355
 356                 $t = new Title();
 357                 $t->mDbkeyform = Title::makeName( $ns, $title, $fragment, $interwiki );
 358                 if ( $t->secureAndSplit() ) {
 359                         return $t;
 360                 } else {
 361                         return null;
 362                 }
 363         }
 364
 365         /**
 366          * Create a new Title for the Main Page
 367          *
 368          * @return Title the new object
 369          */
 370         public static function newMainPage() {
 371                 $title = Title::newFromText( wfMessage( 'mainpage' )->inContentLanguage()->text() );
 372                 // Don't give fatal errors if the message is broken
 373                 if ( !$title ) {
 374                         $title = Title::newFromText( 'Main Page' );
 375                 }
 376                 return $title;
 377         }
 378
 379         /**
 380          * Extract a redirect destination from a string and return the
 381          * Title, or null if the text doesn't contain a valid redirect
 382          * This will only return the very next target, useful for
 383          * the redirect table and other checks that don't need full recursion
 384          *
 385          * @param $text String: Text with possible redirect
 386          * @return Title: The corresponding Title
 387          * @deprecated since 1.21, use Content::getRedirectTarget instead.
 388          */
 389         public static function newFromRedirect( $text ) {
 390                 ContentHandler::deprecated( __METHOD__, '1.21' );
 391
 392                 $content = ContentHandler::makeContent( $text, null, CONTENT_MODEL_WIKITEXT );
 393                 return $content->getRedirectTarget();
 394         }
 395
 396         /**
 397          * Extract a redirect destination from a string and return the
 398          * Title, or null if the text doesn't contain a valid redirect
 399          * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
 400          * in order to provide (hopefully) the Title of the final destination instead of another redirect
 401          *
 402          * @param $text String Text with possible redirect
 403          * @return Title
 404          * @deprecated since 1.21, use Content::getUltimateRedirectTarget instead.
 405          */
 406         public static function newFromRedirectRecurse( $text ) {
 407                 ContentHandler::deprecated( __METHOD__, '1.21' );
 408
 409                 $content = ContentHandler::makeContent( $text, null, CONTENT_MODEL_WIKITEXT );
 410                 return $content->getUltimateRedirectTarget();
 411         }
 412
 413         /**
 414          * Extract a redirect destination from a string and return an
 415          * array of Titles, or null if the text doesn't contain a valid redirect
 416          * The last element in the array is the final destination after all redirects
 417          * have been resolved (up to $wgMaxRedirects times)
 418          *
 419          * @param $text String Text with possible redirect
 420          * @return Array of Titles, with the destination last
 421          * @deprecated since 1.21, use Content::getRedirectChain instead.
 422          */
 423         public static function newFromRedirectArray( $text ) {
 424                 ContentHandler::deprecated( __METHOD__, '1.21' );
 425
 426                 $content = ContentHandler::makeContent( $text, null, CONTENT_MODEL_WIKITEXT );
 427                 return $content->getRedirectChain();
 428         }
 429
 430         /**
 431          * Get the prefixed DB key associated with an ID
 432          *
 433          * @param $id Int the page_id of the article
 434          * @return Title an object representing the article, or NULL if no such article was found
 435          */
 436         public static function nameOf( $id ) {
 437                 $dbr = wfGetDB( DB_SLAVE );
 438
 439                 $s = $dbr->selectRow(
 440                         'page',
 441                         array( 'page_namespace', 'page_title' ),
 442                         array( 'page_id' => $id ),
 443                         __METHOD__
 444                 );
 445                 if ( $s === false ) {
 446                         return null;
 447                 }
 448
 449                 $n = self::makeName( $s->page_namespace, $s->page_title );
 450                 return $n;
 451         }
 452
 453         /**
 454          * Get a regex character class describing the legal characters in a link
 455          *
 456          * @return String the list of characters, not delimited
 457          */
 458         public static function legalChars() {
 459                 global $wgLegalTitleChars;
 460                 return $wgLegalTitleChars;
 461         }
 462
 463         /**
 464          * Returns a simple regex that will match on characters and sequences invalid in titles.
 465          * Note that this doesn't pick up many things that could be wrong with titles, but that
 466          * replacing this regex with something valid will make many titles valid.
 467          *
 468          * @return String regex string
 469          */
 470         static function getTitleInvalidRegex() {
 471                 static $rxTc = false;
 472                 if ( !$rxTc ) {
 473                         # Matching titles will be held as illegal.
 474                         $rxTc = '/' .
 475                                 # Any character not allowed is forbidden...
 476                                 '[^' . self::legalChars() . ']' .
 477                                 # URL percent encoding sequences interfere with the ability
 478                                 # to round-trip titles -- you can't link to them consistently.
 479                                 '|%[0-9A-Fa-f]{2}' .
 480                                 # XML/HTML character references produce similar issues.
 481                                 '|&[A-Za-z0-9\x80-\xff]+;' .
 482                                 '|&#[0-9]+;' .
 483                                 '|&#x[0-9A-Fa-f]+;' .
 484                                 '/S';
 485                 }
 486
 487                 return $rxTc;
 488         }
 489
 490         /**
 491          * Get a string representation of a title suitable for
 492          * including in a search index
 493          *
 494          * @param $ns Int a namespace index
 495          * @param $title String text-form main part
 496          * @return String a stripped-down title string ready for the search index
 497          */
 498         public static function indexTitle( $ns, $title ) {
 499                 global $wgContLang;
 500
 501                 $lc = SearchEngine::legalSearchChars() . '&#;';
 502                 $t = $wgContLang->normalizeForSearch( $title );
 503                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 504                 $t = $wgContLang->lc( $t );
 505
 506                 # Handle 's, s'
 507                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 508                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 509
 510                 $t = preg_replace( "/\\s+/", ' ', $t );
 511
 512                 if ( $ns == NS_FILE ) {
 513                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 514                 }
 515                 return trim( $t );
 516         }
 517
 518         /**
 519          * Make a prefixed DB key from a DB key and a namespace index
 520          *
 521          * @param $ns Int numerical representation of the namespace
 522          * @param $title String the DB key form the title
 523          * @param $fragment String The link fragment (after the "#")
 524          * @param $interwiki String The interwiki prefix
 525          * @return String the prefixed form of the title
 526          */
 527         public static function makeName( $ns, $title, $fragment = '', $interwiki = '' ) {
 528                 global $wgContLang;
 529
 530                 $namespace = $wgContLang->getNsText( $ns );
 531                 $name = $namespace == '' ? $title : "$namespace:$title";
 532                 if ( strval( $interwiki ) != '' ) {
 533                         $name = "$interwiki:$name";
 534                 }
 535                 if ( strval( $fragment ) != '' ) {
 536                         $name .= '#' . $fragment;
 537                 }
 538                 return $name;
 539         }
 540
 541         /**
 542          * Escape a text fragment, say from a link, for a URL
 543          *
 544          * @param $fragment string containing a URL or link fragment (after the "#")
 545          * @return String: escaped string
 546          */
 547         static function escapeFragmentForURL( $fragment ) {
 548                 # Note that we don't urlencode the fragment.  urlencoded Unicode
 549                 # fragments appear not to work in IE (at least up to 7) or in at least
 550                 # one version of Opera 9.x.  The W3C validator, for one, doesn't seem
 551                 # to care if they aren't encoded.
 552                 return Sanitizer::escapeId( $fragment, 'noninitial' );
 553         }
 554
 555         /**
 556          * Callback for usort() to do title sorts by (namespace, title)
 557          *
 558          * @param $a Title
 559          * @param $b Title
 560          *
 561          * @return Integer: result of string comparison, or namespace comparison
 562          */
 563         public static function compare( $a, $b ) {
 564                 if ( $a->getNamespace() == $b->getNamespace() ) {
 565                         return strcmp( $a->getText(), $b->getText() );
 566                 } else {
 567                         return $a->getNamespace() - $b->getNamespace();
 568                 }
 569         }
 570
 571         /**
 572          * Determine whether the object refers to a page within
 573          * this project.
 574          *
 575          * @return Bool TRUE if this is an in-project interwiki link or a wikilink, FALSE otherwise
 576          */
 577         public function isLocal() {
 578                 if ( $this->mInterwiki != '' ) {
 579                         return Interwiki::fetch( $this->mInterwiki )->isLocal();
 580                 } else {
 581                         return true;
 582                 }
 583         }
 584
 585         /**
 586          * Is this Title interwiki?
 587          *
 588          * @return Bool
 589          */
 590         public function isExternal() {
 591                 return ( $this->mInterwiki != '' );
 592         }
 593
 594         /**
 595          * Get the interwiki prefix (or null string)
 596          *
 597          * @return String Interwiki prefix
 598          */
 599         public function getInterwiki() {
 600                 return $this->mInterwiki;
 601         }
 602
 603         /**
 604          * Determine whether the object refers to a page within
 605          * this project and is transcludable.
 606          *
 607          * @return Bool TRUE if this is transcludable
 608          */
 609         public function isTrans() {
 610                 if ( $this->mInterwiki == '' ) {
 611                         return false;
 612                 }
 613
 614                 return Interwiki::fetch( $this->mInterwiki )->isTranscludable();
 615         }
 616
 617         /**
 618          * Returns the DB name of the distant wiki which owns the object.
 619          *
 620          * @return String the DB name
 621          */
 622         public function getTransWikiID() {
 623                 if ( $this->mInterwiki == '' ) {
 624                         return false;
 625                 }
 626
 627                 return Interwiki::fetch( $this->mInterwiki )->getWikiID();
 628         }
 629
 630         /**
 631          * Get the text form (spaces not underscores) of the main part
 632          *
 633          * @return String Main part of the title
 634          */
 635         public function getText() {
 636                 return $this->mTextform;
 637         }
 638
 639         /**
 640          * Get the URL-encoded form of the main part
 641          *
 642          * @return String Main part of the title, URL-encoded
 643          */
 644         public function getPartialURL() {
 645                 return $this->mUrlform;
 646         }
 647
 648         /**
 649          * Get the main part with underscores
 650          *
 651          * @return String: Main part of the title, with underscores
 652          */
 653         public function getDBkey() {
 654                 return $this->mDbkeyform;
 655         }
 656
 657         /**
 658          * Get the DB key with the initial letter case as specified by the user
 659          *
 660          * @return String DB key
 661          */
 662         function getUserCaseDBKey() {
 663                 return $this->mUserCaseDBKey;
 664         }
 665
 666         /**
 667          * Get the namespace index, i.e. one of the NS_xxxx constants.
 668          *
 669          * @return Integer: Namespace index
 670          */
 671         public function getNamespace() {
 672                 return $this->mNamespace;
 673         }
 674
 675         /**
 676          * Get the page's content model id, see the CONTENT_MODEL_XXX constants.
 677          *
 678          * @throws MWException
 679          * @return String: Content model id
 680          */
 681         public function getContentModel() {
 682                 if ( !$this->mContentModel ) {
 683                         $linkCache = LinkCache::singleton();
 684                         $linkCache->addLinkObj( $this );
 685                         $this->mContentModel = $linkCache->getGoodLinkFieldObj( $this, 'model' );
 686                 }
 687
 688                 if ( !$this->mContentModel ) {
 689                         $this->mContentModel = ContentHandler::getDefaultModelFor( $this );
 690                 }
 691
 692                 if( !$this->mContentModel ) {
 693                         throw new MWException( 'Failed to determine content model!' );
 694                 }
 695
 696                 return $this->mContentModel;
 697         }
 698
 699         /**
 700          * Convenience method for checking a title's content model name
 701          *
 702          * @param String $id The content model ID (use the CONTENT_MODEL_XXX constants).
 703          * @return Boolean true if $this->getContentModel() == $id
 704          */
 705         public function hasContentModel( $id ) {
 706                 return $this->getContentModel() == $id;
 707         }
 708
 709         /**
 710          * Get the namespace text
 711          *
 712          * @return String: Namespace text
 713          */
 714         public function getNsText() {
 715                 global $wgContLang;
 716
 717                 if ( $this->mInterwiki != '' ) {
 718                         // This probably shouldn't even happen. ohh man, oh yuck.
 719                         // But for interwiki transclusion it sometimes does.
 720                         // Shit. Shit shit shit.
 721                         //
 722                         // Use the canonical namespaces if possible to try to
 723                         // resolve a foreign namespace.
 724                         if ( MWNamespace::exists( $this->mNamespace ) ) {
 725                                 return MWNamespace::getCanonicalName( $this->mNamespace );
 726                         }
 727                 }
 728
 729                 if ( $wgContLang->needsGenderDistinction() &&
 730                                 MWNamespace::hasGenderDistinction( $this->mNamespace ) ) {
 731                         $gender = GenderCache::singleton()->getGenderOf( $this->getText(), __METHOD__ );
 732                         return $wgContLang->getGenderNsText( $this->mNamespace, $gender );
 733                 }
 734
 735                 return $wgContLang->getNsText( $this->mNamespace );
 736         }
 737
 738         /**
 739          * Get the namespace text of the subject (rather than talk) page
 740          *
 741          * @return String Namespace text
 742          */
 743         public function getSubjectNsText() {
 744                 global $wgContLang;
 745                 return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
 746         }
 747
 748         /**
 749          * Get the namespace text of the talk page
 750          *
 751          * @return String Namespace text
 752          */
 753         public function getTalkNsText() {
 754                 global $wgContLang;
 755                 return( $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) ) );
 756         }
 757
 758         /**
 759          * Could this title have a corresponding talk page?
 760          *
 761          * @return Bool TRUE or FALSE
 762          */
 763         public function canTalk() {
 764                 return( MWNamespace::canTalk( $this->mNamespace ) );
 765         }
 766
 767         /**
 768          * Is this in a namespace that allows actual pages?
 769          *
 770          * @return Bool
 771          * @internal note -- uses hardcoded namespace index instead of constants
 772          */
 773         public function canExist() {
 774                 return $this->mNamespace >= NS_MAIN;
 775         }
 776
 777         /**
 778          * Can this title be added to a user's watchlist?
 779          *
 780          * @return Bool TRUE or FALSE
 781          */
 782         public function isWatchable() {
 783                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
 784         }
 785
 786         /**
 787          * Returns true if this is a special page.
 788          *
 789          * @return boolean
 790          */
 791         public function isSpecialPage() {
 792                 return $this->getNamespace() == NS_SPECIAL;
 793         }
 794
 795         /**
 796          * Returns true if this title resolves to the named special page
 797          *
 798          * @param $name String The special page name
 799          * @return boolean
 800          */
 801         public function isSpecial( $name ) {
 802                 if ( $this->isSpecialPage() ) {
 803                         list( $thisName, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $this->getDBkey() );
 804                         if ( $name == $thisName ) {
 805                                 return true;
 806                         }
 807                 }
 808                 return false;
 809         }
 810
 811         /**
 812          * If the Title refers to a special page alias which is not the local default, resolve
 813          * the alias, and localise the name as necessary.  Otherwise, return $this
 814          *
 815          * @return Title
 816          */
 817         public function fixSpecialName() {
 818                 if ( $this->isSpecialPage() ) {
 819                         list( $canonicalName, $par ) = SpecialPageFactory::resolveAlias( $this->mDbkeyform );
 820                         if ( $canonicalName ) {
 821                                 $localName = SpecialPageFactory::getLocalNameFor( $canonicalName, $par );
 822                                 if ( $localName != $this->mDbkeyform ) {
 823                                         return Title::makeTitle( NS_SPECIAL, $localName );
 824                                 }
 825                         }
 826                 }
 827                 return $this;
 828         }
 829
 830         /**
 831          * Returns true if the title is inside the specified namespace.
 832          *
 833          * Please make use of this instead of comparing to getNamespace()
 834          * This function is much more resistant to changes we may make
 835          * to namespaces than code that makes direct comparisons.
 836          * @param $ns int The namespace
 837          * @return bool
 838          * @since 1.19
 839          */
 840         public function inNamespace( $ns ) {
 841                 return MWNamespace::equals( $this->getNamespace(), $ns );
 842         }
 843
 844         /**
 845          * Returns true if the title is inside one of the specified namespaces.
 846          *
 847          * @param ...$namespaces The namespaces to check for
 848          * @return bool
 849          * @since 1.19
 850          */
 851         public function inNamespaces( /* ... */ ) {
 852                 $namespaces = func_get_args();
 853                 if ( count( $namespaces ) > 0 && is_array( $namespaces[0] ) ) {
 854                         $namespaces = $namespaces[0];
 855                 }
 856
 857                 foreach ( $namespaces as $ns ) {
 858                         if ( $this->inNamespace( $ns ) ) {
 859                                 return true;
 860                         }
 861                 }
 862
 863                 return false;
 864         }
 865
 866         /**
 867          * Returns true if the title has the same subject namespace as the
 868          * namespace specified.
 869          * For example this method will take NS_USER and return true if namespace
 870          * is either NS_USER or NS_USER_TALK since both of them have NS_USER
 871          * as their subject namespace.
 872          *
 873          * This is MUCH simpler than individually testing for equivilance
 874          * against both NS_USER and NS_USER_TALK, and is also forward compatible.
 875          * @since 1.19
 876          * @param $ns int
 877          * @return bool
 878          */
 879         public function hasSubjectNamespace( $ns ) {
 880                 return MWNamespace::subjectEquals( $this->getNamespace(), $ns );
 881         }
 882
 883         /**
 884          * Is this Title in a namespace which contains content?
 885          * In other words, is this a content page, for the purposes of calculating
 886          * statistics, etc?
 887          *
 888          * @return Boolean
 889          */
 890         public function isContentPage() {
 891                 return MWNamespace::isContent( $this->getNamespace() );
 892         }
 893
 894         /**
 895          * Would anybody with sufficient privileges be able to move this page?
 896          * Some pages just aren't movable.
 897          *
 898          * @return Bool TRUE or FALSE
 899          */
 900         public function isMovable() {
 901                 if ( !MWNamespace::isMovable( $this->getNamespace() ) || $this->getInterwiki() != '' ) {
 902                         // Interwiki title or immovable namespace. Hooks don't get to override here
 903                         return false;
 904                 }
 905
 906                 $result = true;
 907                 wfRunHooks( 'TitleIsMovable', array( $this, &$result ) );
 908                 return $result;
 909         }
 910
 911         /**
 912          * Is this the mainpage?
 913          * @note Title::newFromText seems to be sufficiently optimized by the title
 914          * cache that we don't need to over-optimize by doing direct comparisons and
 915          * acidentally creating new bugs where $title->equals( Title::newFromText() )
 916          * ends up reporting something differently than $title->isMainPage();
 917          *
 918          * @since 1.18
 919          * @return Bool
 920          */
 921         public function isMainPage() {
 922                 return $this->equals( Title::newMainPage() );
 923         }
 924
 925         /**
 926          * Is this a subpage?
 927          *
 928          * @return Bool
 929          */
 930         public function isSubpage() {
 931                 return MWNamespace::hasSubpages( $this->mNamespace )
 932                         ? strpos( $this->getText(), '/' ) !== false
 933                         : false;
 934         }
 935
 936         /**
 937          * Is this a conversion table for the LanguageConverter?
 938          *
 939          * @return Bool
 940          */
 941         public function isConversionTable() {
 942                 //@todo: ConversionTable should become a separate content model.
 943
 944                 return $this->getNamespace() == NS_MEDIAWIKI &&
 945                         strpos( $this->getText(), 'Conversiontable/' ) === 0;
 946         }
 947
 948         /**
 949          * Does that page contain wikitext, or it is JS, CSS or whatever?
 950          *
 951          * @return Bool
 952          */
 953         public function isWikitextPage() {
 954                 return $this->hasContentModel( CONTENT_MODEL_WIKITEXT );
 955         }
 956
 957         /**
 958          * Could this page contain custom CSS or JavaScript for the global UI.
 959          * This is generally true for pages in the MediaWiki namespace having CONTENT_MODEL_CSS
 960          * or CONTENT_MODEL_JAVASCRIPT.
 961          *
 962          * This method does *not* return true for per-user JS/CSS. Use isCssJsSubpage() for that!
 963          *
 964          * Note that this method should not return true for pages that contain and show "inactive" CSS or JS.
 965          *
 966          * @return Bool
 967          */
 968         public function isCssOrJsPage() {
 969                 $isCssOrJsPage = NS_MEDIAWIKI == $this->mNamespace
 970                         && ( $this->hasContentModel( CONTENT_MODEL_CSS )
 971                                 || $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
 972
 973                 #NOTE: this hook is also called in ContentHandler::getDefaultModel. It's called here again to make sure
 974                 #      hook funktions can force this method to return true even outside the mediawiki namespace.
 975
 976                 wfRunHooks( 'TitleIsCssOrJsPage', array( $this, &$isCssOrJsPage ) );
 977
 978                 return $isCssOrJsPage;
 979         }
 980
 981         /**
 982          * Is this a .css or .js subpage of a user page?
 983          * @return Bool
 984          */
 985         public function isCssJsSubpage() {
 986                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
 987                                 && ( $this->hasContentModel( CONTENT_MODEL_CSS )
 988                                         || $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) ) );
 989         }
 990
 991         /**
 992          * Trim down a .css or .js subpage title to get the corresponding skin name
 993          *
 994          * @return string containing skin name from .css or .js subpage title
 995          */
 996         public function getSkinFromCssJsSubpage() {
 997                 $subpage = explode( '/', $this->mTextform );
 998                 $subpage = $subpage[ count( $subpage ) - 1 ];
 999                 $lastdot = strrpos( $subpage, '.' );
1000                 if ( $lastdot === false )
1001                         return $subpage; # Never happens: only called for names ending in '.css' or '.js'
1002                 return substr( $subpage, 0, $lastdot );
1003         }
1004
1005         /**
1006          * Is this a .css subpage of a user page?
1007          *
1008          * @return Bool
1009          */
1010         public function isCssSubpage() {
1011                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
1012                         && $this->hasContentModel( CONTENT_MODEL_CSS ) );
1013         }
1014
1015         /**
1016          * Is this a .js subpage of a user page?
1017          *
1018          * @return Bool
1019          */
1020         public function isJsSubpage() {
1021                 return ( NS_USER == $this->mNamespace && $this->isSubpage()
1022                         && $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
1023         }
1024
1025         /**
1026          * Is this a talk page of some sort?
1027          *
1028          * @return Bool
1029          */
1030         public function isTalkPage() {
1031                 return MWNamespace::isTalk( $this->getNamespace() );
1032         }
1033
1034         /**
1035          * Get a Title object associated with the talk page of this article
1036          *
1037          * @return Title the object for the talk page
1038          */
1039         public function getTalkPage() {
1040                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1041         }
1042
1043         /**
1044          * Get a title object associated with the subject page of this
1045          * talk page
1046          *
1047          * @return Title the object for the subject page
1048          */
1049         public function getSubjectPage() {
1050                 // Is this the same title?
1051                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
1052                 if ( $this->getNamespace() == $subjectNS ) {
1053                         return $this;
1054                 }
1055                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
1056         }
1057
1058         /**
1059          * Get the default namespace index, for when there is no namespace
1060          *
1061          * @return Int Default namespace index
1062          */
1063         public function getDefaultNamespace() {
1064                 return $this->mDefaultNamespace;
1065         }
1066
1067         /**
1068          * Get title for search index
1069          *
1070          * @return String a stripped-down title string ready for the
1071          *  search index
1072          */
1073         public function getIndexTitle() {
1074                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
1075         }
1076
1077         /**
1078          * Get the Title fragment (i.e.\ the bit after the #) in text form
1079          *
1080          * @return String Title fragment
1081          */
1082         public function getFragment() {
1083                 return $this->mFragment;
1084         }
1085
1086         /**
1087          * Get the fragment in URL form, including the "#" character if there is one
1088          * @return String Fragment in URL form
1089          */
1090         public function getFragmentForURL() {
1091                 if ( $this->mFragment == '' ) {
1092                         return '';
1093                 } else {
1094                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
1095                 }
1096         }
1097
1098         /**
1099          * Set the fragment for this title. Removes the first character from the
1100          * specified fragment before setting, so it assumes you're passing it with
1101          * an initial "#".
1102          *
1103          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
1104          * Still in active use privately.
1105          *
1106          * @param $fragment String text
1107          */
1108         public function setFragment( $fragment ) {
1109                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
1110         }
1111
1112         /**
1113          * Prefix some arbitrary text with the namespace or interwiki prefix
1114          * of this object
1115          *
1116          * @param $name String the text
1117          * @return String the prefixed text
1118          * @private
1119          */
1120         private function prefix( $name ) {
1121                 $p = '';
1122                 if ( $this->mInterwiki != '' ) {
1123                         $p = $this->mInterwiki . ':';
1124                 }
1125
1126                 if ( 0 != $this->mNamespace ) {
1127                         $p .= $this->getNsText() . ':';
1128                 }
1129                 return $p . $name;
1130         }
1131
1132         /**
1133          * Get the prefixed database key form
1134          *
1135          * @return String the prefixed title, with underscores and
1136          *  any interwiki and namespace prefixes
1137          */
1138         public function getPrefixedDBkey() {
1139                 $s = $this->prefix( $this->mDbkeyform );
1140                 $s = str_replace( ' ', '_', $s );
1141                 return $s;
1142         }
1143
1144         /**
1145          * Get the prefixed title with spaces.
1146          * This is the form usually used for display
1147          *
1148          * @return String the prefixed title, with spaces
1149          */
1150         public function getPrefixedText() {
1151                 // @todo FIXME: Bad usage of empty() ?
1152                 if ( empty( $this->mPrefixedText ) ) {
1153                         $s = $this->prefix( $this->mTextform );
1154                         $s = str_replace( '_', ' ', $s );
1155                         $this->mPrefixedText = $s;
1156                 }
1157                 return $this->mPrefixedText;
1158         }
1159
1160         /**
1161          * Return a string representation of this title
1162          *
1163          * @return String representation of this title
1164          */
1165         public function __toString() {
1166                 return $this->getPrefixedText();
1167         }
1168
1169         /**
1170          * Get the prefixed title with spaces, plus any fragment
1171          * (part beginning with '#')
1172          *
1173          * @return String the prefixed title, with spaces and the fragment, including '#'
1174          */
1175         public function getFullText() {
1176                 $text = $this->getPrefixedText();
1177                 if ( $this->mFragment != '' ) {
1178                         $text .= '#' . $this->mFragment;
1179                 }
1180                 return $text;
1181         }
1182
1183         /**
1184          * Get the root page name text without a namespace, i.e. the leftmost part before any slashes
1185          *
1186          * @par Example:
1187          * @code
1188          * Title::newFromText('User:Foo/Bar/Baz')->getRootText();
1189          * # returns: 'Foo'
1190          * @endcode
1191          *
1192          * @return String Root name
1193          * @since 1.20
1194          */
1195         public function getRootText() {
1196                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1197                         return $this->getText();
1198                 }
1199
1200                 return strtok( $this->getText(), '/' );
1201         }
1202
1203         /**
1204          * Get the root page name title, i.e. the leftmost part before any slashes
1205          *
1206          * @par Example:
1207          * @code
1208          * Title::newFromText('User:Foo/Bar/Baz')->getRootTitle();
1209          * # returns: Title{User:Foo}
1210          * @endcode
1211          *
1212          * @return Title Root title
1213          * @since 1.20
1214          */
1215         public function getRootTitle() {
1216                 return Title::makeTitle( $this->getNamespace(), $this->getRootText() );
1217         }
1218
1219         /**
1220          * Get the base page name without a namespace, i.e. the part before the subpage name
1221          *
1222          * @par Example:
1223          * @code
1224          * Title::newFromText('User:Foo/Bar/Baz')->getBaseText();
1225          * # returns: 'Foo/Bar'
1226          * @endcode
1227          *
1228          * @return String Base name
1229          */
1230         public function getBaseText() {
1231                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1232                         return $this->getText();
1233                 }
1234
1235                 $parts = explode( '/', $this->getText() );
1236                 # Don't discard the real title if there's no subpage involved
1237                 if ( count( $parts ) > 1 ) {
1238                         unset( $parts[count( $parts ) - 1] );
1239                 }
1240                 return implode( '/', $parts );
1241         }
1242
1243         /**
1244          * Get the base page name title, i.e. the part before the subpage name
1245          *
1246          * @par Example:
1247          * @code
1248          * Title::newFromText('User:Foo/Bar/Baz')->getBaseTitle();
1249          * # returns: Title{User:Foo/Bar}
1250          * @endcode
1251          *
1252          * @return Title Base title
1253          * @since 1.20
1254          */
1255         public function getBaseTitle() {
1256                 return Title::makeTitle( $this->getNamespace(), $this->getBaseText() );
1257         }
1258
1259         /**
1260          * Get the lowest-level subpage name, i.e. the rightmost part after any slashes
1261          *
1262          * @par Example:
1263          * @code
1264          * Title::newFromText('User:Foo/Bar/Baz')->getSubpageText();
1265          * # returns: "Baz"
1266          * @endcode
1267          *
1268          * @return String Subpage name
1269          */
1270         public function getSubpageText() {
1271                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1272                         return( $this->mTextform );
1273                 }
1274                 $parts = explode( '/', $this->mTextform );
1275                 return( $parts[count( $parts ) - 1] );
1276         }
1277
1278         /**
1279          * Get the title for a subpage of the current page
1280          *
1281          * @par Example:
1282          * @code
1283          * Title::newFromText('User:Foo/Bar/Baz')->getSubpage("Asdf");
1284          * # returns: Title{User:Foo/Bar/Baz/Asdf}
1285          * @endcode
1286          *
1287          * @param $text String The subpage name to add to the title
1288          * @return Title Subpage title
1289          * @since 1.20
1290          */
1291         public function getSubpage( $text ) {
1292                 return Title::makeTitleSafe( $this->getNamespace(), $this->getText() . '/' . $text );
1293         }
1294
1295         /**
1296          * Get the HTML-escaped displayable text form.
1297          * Used for the title field in <a> tags.
1298          *
1299          * @return String the text, including any prefixes
1300          */
1301         public function getEscapedText() {
1302                 wfDeprecated( __METHOD__, '1.19' );
1303                 return htmlspecialchars( $this->getPrefixedText() );
1304         }
1305
1306         /**
1307          * Get a URL-encoded form of the subpage text
1308          *
1309          * @return String URL-encoded subpage name
1310          */
1311         public function getSubpageUrlForm() {
1312                 $text = $this->getSubpageText();
1313                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
1314                 return( $text );
1315         }
1316
1317         /**
1318          * Get a URL-encoded title (not an actual URL) including interwiki
1319          *
1320          * @return String the URL-encoded form
1321          */
1322         public function getPrefixedURL() {
1323                 $s = $this->prefix( $this->mDbkeyform );
1324                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
1325                 return $s;
1326         }
1327
1328         /**
1329          * Helper to fix up the get{Local,Full,Link,Canonical}URL args
1330          * get{Canonical,Full,Link,Local}URL methods accepted an optional
1331          * second argument named variant. This was deprecated in favor
1332          * of passing an array of option with a "variant" key
1333          * Once $query2 is removed for good, this helper can be dropped
1334          * andthe wfArrayToCgi moved to getLocalURL();
1335          *
1336          * @since 1.19 (r105919)
1337          * @param $query
1338          * @param $query2 bool
1339          * @return String
1340          */
1341         private static function fixUrlQueryArgs( $query, $query2 = false ) {
1342                 if( $query2 !== false ) {
1343                         wfDeprecated( "Title::get{Canonical,Full,Link,Local} method called with a second parameter is deprecated. Add your parameter to an array passed as the first parameter.", "1.19" );
1344                 }
1345                 if ( is_array( $query ) ) {
1346                         $query = wfArrayToCgi( $query );
1347                 }
1348                 if ( $query2 ) {
1349                         if ( is_string( $query2 ) ) {
1350                                 // $query2 is a string, we will consider this to be
1351                                 // a deprecated $variant argument and add it to the query
1352                                 $query2 = wfArrayToCgi( array( 'variant' => $query2 ) );
1353                         } else {
1354                                 $query2 = wfArrayToCgi( $query2 );
1355                         }
1356                         // If we have $query content add a & to it first
1357                         if ( $query ) {
1358                                 $query .= '&';
1359                         }
1360                         // Now append the queries together
1361                         $query .= $query2;
1362                 }
1363                 return $query;
1364         }
1365
1366         /**
1367          * Get a real URL referring to this title, with interwiki link and
1368          * fragment
1369          *
1370          * See getLocalURL for the arguments.
1371          *
1372          * @see self::getLocalURL
1373          * @see wfExpandUrl
1374          * @param $query
1375          * @param $query2 bool
1376          * @param $proto Protocol type to use in URL
1377          * @return String the URL
1378          */
1379         public function getFullURL( $query = '', $query2 = false, $proto = PROTO_RELATIVE ) {
1380                 $query = self::fixUrlQueryArgs( $query, $query2 );
1381
1382                 # Hand off all the decisions on urls to getLocalURL
1383                 $url = $this->getLocalURL( $query );
1384
1385                 # Expand the url to make it a full url. Note that getLocalURL has the
1386                 # potential to output full urls for a variety of reasons, so we use
1387                 # wfExpandUrl instead of simply prepending $wgServer
1388                 $url = wfExpandUrl( $url, $proto );
1389
1390                 # Finally, add the fragment.
1391                 $url .= $this->getFragmentForURL();
1392
1393                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
1394                 return $url;
1395         }
1396
1397         /**
1398          * Get a URL with no fragment or server name.  If this page is generated
1399          * with action=render, $wgServer is prepended.
1400          *
1401
1402          * @param $query string|array an optional query string,
1403          *   not used for interwiki links. Can be specified as an associative array as well,
1404          *   e.g., array( 'action' => 'edit' ) (keys and values will be URL-escaped).
1405          *   Some query patterns will trigger various shorturl path replacements.
1406          * @param $query2 Mixed: An optional secondary query array. This one MUST
1407          *   be an array. If a string is passed it will be interpreted as a deprecated
1408          *   variant argument and urlencoded into a variant= argument.
1409          *   This second query argument will be added to the $query
1410          *   The second parameter is deprecated since 1.19. Pass it as a key,value
1411          *   pair in the first parameter array instead.
1412          *
1413          * @return String the URL
1414          */
1415         public function getLocalURL( $query = '', $query2 = false ) {
1416                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
1417
1418                 $query = self::fixUrlQueryArgs( $query, $query2 );
1419
1420                 $interwiki = Interwiki::fetch( $this->mInterwiki );
1421                 if ( $interwiki ) {
1422                         $namespace = $this->getNsText();
1423                         if ( $namespace != '' ) {
1424                                 # Can this actually happen? Interwikis shouldn't be parsed.
1425                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
1426                                 $namespace .= ':';
1427                         }
1428                         $url = $interwiki->getURL( $namespace . $this->getDBkey() );
1429                         $url = wfAppendQuery( $url, $query );
1430                 } else {
1431                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
1432                         if ( $query == '' ) {
1433                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
1434                                 wfRunHooks( 'GetLocalURL::Article', array( &$this, &$url ) );
1435                         } else {
1436                                 global $wgVariantArticlePath, $wgActionPaths;
1437                                 $url = false;
1438                                 $matches = array();
1439
1440                                 if ( !empty( $wgActionPaths ) &&
1441                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
1442                                 {
1443                                         $action = urldecode( $matches[2] );
1444                                         if ( isset( $wgActionPaths[$action] ) ) {
1445                                                 $query = $matches[1];
1446                                                 if ( isset( $matches[4] ) ) {
1447                                                         $query .= $matches[4];
1448                                                 }
1449                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
1450                                                 if ( $query != '' ) {
1451                                                         $url = wfAppendQuery( $url, $query );
1452                                                 }
1453                                         }
1454                                 }
1455
1456                                 if ( $url === false &&
1457                                         $wgVariantArticlePath &&
1458                                         $this->getPageLanguage()->hasVariants() &&
1459                                         preg_match( '/^variant=([^&]*)$/', $query, $matches ) )
1460                                 {
1461                                         $variant = urldecode( $matches[1] );
1462                                         if ( $this->getPageLanguage()->hasVariant( $variant ) ) {
1463                                                 // Only do the variant replacement if the given variant is a valid
1464                                                 // variant for the page's language.
1465                                                 $url = str_replace( '$2', urlencode( $variant ), $wgVariantArticlePath );
1466                                                 $url = str_replace( '$1', $dbkey, $url );
1467                                         }
1468                                 }
1469
1470                                 if ( $url === false ) {
1471                                         if ( $query == '-' ) {
1472                                                 $query = '';
1473                                         }
1474                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
1475                                 }
1476                         }
1477
1478                         wfRunHooks( 'GetLocalURL::Internal', array( &$this, &$url, $query ) );
1479
1480                         // @todo FIXME: This causes breakage in various places when we
1481                         // actually expected a local URL and end up with dupe prefixes.
1482                         if ( $wgRequest->getVal( 'action' ) == 'render' ) {
1483                                 $url = $wgServer . $url;
1484                         }
1485                 }
1486                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
1487                 return $url;
1488         }
1489
1490         /**
1491          * Get a URL that's the simplest URL that will be valid to link, locally,
1492          * to the current Title.  It includes the fragment, but does not include
1493          * the server unless action=render is used (or the link is external).  If
1494          * there's a fragment but the prefixed text is empty, we just return a link
1495          * to the fragment.
1496          *
1497          * The result obviously should not be URL-escaped, but does need to be
1498          * HTML-escaped if it's being output in HTML.
1499          *
1500          * See getLocalURL for the arguments.
1501          *
1502          * @param $query
1503          * @param $query2 bool
1504          * @param $proto Protocol to use; setting this will cause a full URL to be used
1505          * @see self::getLocalURL
1506          * @return String the URL
1507          */
1508         public function getLinkURL( $query = '', $query2 = false, $proto = PROTO_RELATIVE ) {
1509                 wfProfileIn( __METHOD__ );
1510                 if ( $this->isExternal() || $proto !== PROTO_RELATIVE ) {
1511                         $ret = $this->getFullURL( $query, $query2, $proto );
1512                 } elseif ( $this->getPrefixedText() === '' && $this->getFragment() !== '' ) {
1513                         $ret = $this->getFragmentForURL();
1514                 } else {
1515                         $ret = $this->getLocalURL( $query, $query2 ) . $this->getFragmentForURL();
1516                 }
1517                 wfProfileOut( __METHOD__ );
1518                 return $ret;
1519         }
1520
1521         /**
1522          * Get an HTML-escaped version of the URL form, suitable for
1523          * using in a link, without a server name or fragment
1524          *
1525          * See getLocalURL for the arguments.
1526          *
1527          * @see self::getLocalURL
1528          * @param $query string
1529          * @param $query2 bool|string
1530          * @return String the URL
1531          */
1532         public function escapeLocalURL( $query = '', $query2 = false ) {
1533                 wfDeprecated( __METHOD__, '1.19' );
1534                 return htmlspecialchars( $this->getLocalURL( $query, $query2 ) );
1535         }
1536
1537         /**
1538          * Get an HTML-escaped version of the URL form, suitable for
1539          * using in a link, including the server name and fragment
1540          *
1541          * See getLocalURL for the arguments.
1542          *
1543          * @see self::getLocalURL
1544          * @return String the URL
1545          */
1546         public function escapeFullURL( $query = '', $query2 = false ) {
1547                 wfDeprecated( __METHOD__, '1.19' );
1548                 return htmlspecialchars( $this->getFullURL( $query, $query2 ) );
1549         }
1550
1551         /**
1552          * Get the URL form for an internal link.
1553          * - Used in various Squid-related code, in case we have a different
1554          * internal hostname for the server from the exposed one.
1555          *
1556          * This uses $wgInternalServer to qualify the path, or $wgServer
1557          * if $wgInternalServer is not set. If the server variable used is
1558          * protocol-relative, the URL will be expanded to http://
1559          *
1560          * See getLocalURL for the arguments.
1561          *
1562          * @see self::getLocalURL
1563          * @return String the URL
1564          */
1565         public function getInternalURL( $query = '', $query2 = false ) {
1566                 global $wgInternalServer, $wgServer;
1567                 $query = self::fixUrlQueryArgs( $query, $query2 );
1568                 $server = $wgInternalServer !== false ? $wgInternalServer : $wgServer;
1569                 $url = wfExpandUrl( $server . $this->getLocalURL( $query ), PROTO_HTTP );
1570                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
1571                 return $url;
1572         }
1573
1574         /**
1575          * Get the URL for a canonical link, for use in things like IRC and
1576          * e-mail notifications. Uses $wgCanonicalServer and the
1577          * GetCanonicalURL hook.
1578          *
1579          * NOTE: Unlike getInternalURL(), the canonical URL includes the fragment
1580          *
1581          * See getLocalURL for the arguments.
1582          *
1583          * @see self::getLocalURL
1584          * @return string The URL
1585          * @since 1.18
1586          */
1587         public function getCanonicalURL( $query = '', $query2 = false ) {
1588                 $query = self::fixUrlQueryArgs( $query, $query2 );
1589                 $url = wfExpandUrl( $this->getLocalURL( $query ) . $this->getFragmentForURL(), PROTO_CANONICAL );
1590                 wfRunHooks( 'GetCanonicalURL', array( &$this, &$url, $query ) );
1591                 return $url;
1592         }
1593
1594         /**
1595          * HTML-escaped version of getCanonicalURL()
1596          *
1597          * See getLocalURL for the arguments.
1598          *
1599          * @see self::getLocalURL
1600          * @since 1.18
1601          * @return string
1602          */
1603         public function escapeCanonicalURL( $query = '', $query2 = false ) {
1604                 wfDeprecated( __METHOD__, '1.19' );
1605                 return htmlspecialchars( $this->getCanonicalURL( $query, $query2 ) );
1606         }
1607
1608         /**
1609          * Get the edit URL for this Title
1610          *
1611          * @return String the URL, or a null string if this is an
1612          *  interwiki link
1613          */
1614         public function getEditURL() {
1615                 if ( $this->mInterwiki != '' ) {
1616                         return '';
1617                 }
1618                 $s = $this->getLocalURL( 'action=edit' );
1619
1620                 return $s;
1621         }
1622
1623         /**
1624          * Is $wgUser watching this page?
1625          *
1626          * @deprecated in 1.20; use User::isWatched() instead.
1627          * @return Bool
1628          */
1629         public function userIsWatching() {
1630                 global $wgUser;
1631
1632                 if ( is_null( $this->mWatched ) ) {
1633                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn() ) {
1634                                 $this->mWatched = false;
1635                         } else {
1636                                 $this->mWatched = $wgUser->isWatched( $this );
1637                         }
1638                 }
1639                 return $this->mWatched;
1640         }
1641
1642         /**
1643          * Can $wgUser read this page?
1644          *
1645          * @deprecated in 1.19; use userCan(), quickUserCan() or getUserPermissionsErrors() instead
1646          * @return Bool
1647          * @todo fold these checks into userCan()
1648          */
1649         public function userCanRead() {
1650                 wfDeprecated( __METHOD__, '1.19' );
1651                 return $this->userCan( 'read' );
1652         }
1653
1654         /**
1655          * Can $user perform $action on this page?
1656          * This skips potentially expensive cascading permission checks
1657          * as well as avoids expensive error formatting
1658          *
1659          * Suitable for use for nonessential UI controls in common cases, but
1660          * _not_ for functional access control.
1661          *
1662          * May provide false positives, but should never provide a false negative.
1663          *
1664          * @param $action String action that permission needs to be checked for
1665          * @param $user User to check (since 1.19); $wgUser will be used if not
1666          *              provided.
1667          * @return Bool
1668          */
1669         public function quickUserCan( $action, $user = null ) {
1670                 return $this->userCan( $action, $user, false );
1671         }
1672
1673         /**
1674          * Can $user perform $action on this page?
1675          *
1676          * @param $action String action that permission needs to be checked for
1677          * @param $user User to check (since 1.19); $wgUser will be used if not
1678          *   provided.
1679          * @param $doExpensiveQueries Bool Set this to false to avoid doing
1680          *   unnecessary queries.
1681          * @return Bool
1682          */
1683         public function userCan( $action, $user = null, $doExpensiveQueries = true ) {
1684                 if ( !$user instanceof User ) {
1685                         global $wgUser;
1686                         $user = $wgUser;
1687                 }
1688                 return !count( $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries, true ) );
1689         }
1690
1691         /**
1692          * Can $user perform $action on this page?
1693          *
1694          * @todo FIXME: This *does not* check throttles (User::pingLimiter()).
1695          *
1696          * @param $action String action that permission needs to be checked for
1697          * @param $user User to check
1698          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary
1699          *   queries by skipping checks for cascading protections and user blocks.
1700          * @param $ignoreErrors Array of Strings Set this to a list of message keys
1701          *   whose corresponding errors may be ignored.
1702          * @return Array of arguments to wfMessage to explain permissions problems.
1703          */
1704         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1705                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1706
1707                 // Remove the errors being ignored.
1708                 foreach ( $errors as $index => $error ) {
1709                         $error_key = is_array( $error ) ? $error[0] : $error;
1710
1711                         if ( in_array( $error_key, $ignoreErrors ) ) {
1712                                 unset( $errors[$index] );
1713                         }
1714                 }
1715
1716                 return $errors;
1717         }
1718
1719         /**
1720          * Permissions checks that fail most often, and which are easiest to test.
1721          *
1722          * @param $action String the action to check
1723          * @param $user User user to check
1724          * @param $errors Array list of current errors
1725          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1726          * @param $short Boolean short circuit on first error
1727          *
1728          * @return Array list of errors
1729          */
1730         private function checkQuickPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1731                 if ( $action == 'create' ) {
1732                         if ( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1733                                  ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) ) {
1734                                 $errors[] = $user->isAnon() ? array( 'nocreatetext' ) : array( 'nocreate-loggedin' );
1735                         }
1736                 } elseif ( $action == 'move' ) {
1737                         if ( !$user->isAllowed( 'move-rootuserpages' )
1738                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1739                                 // Show user page-specific message only if the user can move other pages
1740                                 $errors[] = array( 'cant-move-user-page' );
1741                         }
1742
1743                         // Check if user is allowed to move files if it's a file
1744                         if ( $this->mNamespace == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1745                                 $errors[] = array( 'movenotallowedfile' );
1746                         }
1747
1748                         if ( !$user->isAllowed( 'move' ) ) {
1749                                 // User can't move anything
1750                                 $userCanMove = User::groupHasPermission( 'user', 'move' );
1751                                 $autoconfirmedCanMove = User::groupHasPermission( 'autoconfirmed', 'move' );
1752                                 if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
1753                                         // custom message if logged-in users without any special rights can move
1754                                         $errors[] = array( 'movenologintext' );
1755                                 } else {
1756                                         $errors[] = array( 'movenotallowed' );
1757                                 }
1758                         }
1759                 } elseif ( $action == 'move-target' ) {
1760                         if ( !$user->isAllowed( 'move' ) ) {
1761                                 // User can't move anything
1762                                 $errors[] = array( 'movenotallowed' );
1763                         } elseif ( !$user->isAllowed( 'move-rootuserpages' )
1764                                         && $this->mNamespace == NS_USER && !$this->isSubpage() ) {
1765                                 // Show user page-specific message only if the user can move other pages
1766                                 $errors[] = array( 'cant-move-to-user-page' );
1767                         }
1768                 } elseif ( !$user->isAllowed( $action ) ) {
1769                         $errors[] = $this->missingPermissionError( $action, $short );
1770                 }
1771
1772                 return $errors;
1773         }
1774
1775         /**
1776          * Add the resulting error code to the errors array
1777          *
1778          * @param $errors Array list of current errors
1779          * @param $result Mixed result of errors
1780          *
1781          * @return Array list of errors
1782          */
1783         private function resultToError( $errors, $result ) {
1784                 if ( is_array( $result ) && count( $result ) && !is_array( $result[0] ) ) {
1785                         // A single array representing an error
1786                         $errors[] = $result;
1787                 } elseif ( is_array( $result ) && is_array( $result[0] ) ) {
1788                         // A nested array representing multiple errors
1789                         $errors = array_merge( $errors, $result );
1790                 } elseif ( $result !== '' && is_string( $result ) ) {
1791                         // A string representing a message-id
1792                         $errors[] = array( $result );
1793                 } elseif ( $result === false ) {
1794                         // a generic "We don't want them to do that"
1795                         $errors[] = array( 'badaccess-group0' );
1796                 }
1797                 return $errors;
1798         }
1799
1800         /**
1801          * Check various permission hooks
1802          *
1803          * @param $action String the action to check
1804          * @param $user User user to check
1805          * @param $errors Array list of current errors
1806          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1807          * @param $short Boolean short circuit on first error
1808          *
1809          * @return Array list of errors
1810          */
1811         private function checkPermissionHooks( $action, $user, $errors, $doExpensiveQueries, $short ) {
1812                 // Use getUserPermissionsErrors instead
1813                 $result = '';
1814                 if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1815                         return $result ? array() : array( array( 'badaccess-group0' ) );
1816                 }
1817                 // Check getUserPermissionsErrors hook
1818                 if ( !wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
1819                         $errors = $this->resultToError( $errors, $result );
1820                 }
1821                 // Check getUserPermissionsErrorsExpensive hook
1822                 if ( $doExpensiveQueries && !( $short && count( $errors ) > 0 ) &&
1823                          !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) ) ) {
1824                         $errors = $this->resultToError( $errors, $result );
1825                 }
1826
1827                 return $errors;
1828         }
1829
1830         /**
1831          * Check permissions on special pages & namespaces
1832          *
1833          * @param $action String the action to check
1834          * @param $user User user to check
1835          * @param $errors Array list of current errors
1836          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1837          * @param $short Boolean short circuit on first error
1838          *
1839          * @return Array list of errors
1840          */
1841         private function checkSpecialsAndNSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1842                 # Only 'createaccount' can be performed on special pages,
1843                 # which don't actually exist in the DB.
1844                 if ( NS_SPECIAL == $this->mNamespace && $action !== 'createaccount' ) {
1845                         $errors[] = array( 'ns-specialprotected' );
1846                 }
1847
1848                 # Check $wgNamespaceProtection for restricted namespaces
1849                 if ( $this->isNamespaceProtected( $user ) ) {
1850                         $ns = $this->mNamespace == NS_MAIN ?
1851                                 wfMessage( 'nstab-main' )->text() : $this->getNsText();
1852                         $errors[] = $this->mNamespace == NS_MEDIAWIKI ?
1853                                 array( 'protectedinterface' ) : array( 'namespaceprotected', $ns );
1854                 }
1855
1856                 return $errors;
1857         }
1858
1859         /**
1860          * Check CSS/JS sub-page permissions
1861          *
1862          * @param $action String the action to check
1863          * @param $user User user to check
1864          * @param $errors Array list of current errors
1865          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1866          * @param $short Boolean short circuit on first error
1867          *
1868          * @return Array list of errors
1869          */
1870         private function checkCSSandJSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1871                 # Protect css/js subpages of user pages
1872                 # XXX: this might be better using restrictions
1873                 # XXX: right 'editusercssjs' is deprecated, for backward compatibility only
1874                 if ( $action != 'patrol' && !$user->isAllowed( 'editusercssjs' )
1875                                 && !preg_match( '/^' . preg_quote( $user->getName(), '/' ) . '\//', $this->mTextform ) ) {
1876                         if ( $this->isCssSubpage() && !$user->isAllowed( 'editusercss' ) ) {
1877                                 $errors[] = array( 'customcssprotected' );
1878                         } elseif ( $this->isJsSubpage() && !$user->isAllowed( 'edituserjs' ) ) {
1879                                 $errors[] = array( 'customjsprotected' );
1880                         }
1881                 }
1882
1883                 return $errors;
1884         }
1885
1886         /**
1887          * Check against page_restrictions table requirements on this
1888          * page. The user must possess all required rights for this
1889          * action.
1890          *
1891          * @param $action String the action to check
1892          * @param $user User user to check
1893          * @param $errors Array list of current errors
1894          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1895          * @param $short Boolean short circuit on first error
1896          *
1897          * @return Array list of errors
1898          */
1899         private function checkPageRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1900                 foreach ( $this->getRestrictions( $action ) as $right ) {
1901                         // Backwards compatibility, rewrite sysop -> protect
1902                         if ( $right == 'sysop' ) {
1903                                 $right = 'protect';
1904                         }
1905                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1906                                 // Users with 'editprotected' permission can edit protected pages
1907                                 // without cascading option turned on.
1908                                 if ( $action != 'edit' || !$user->isAllowed( 'editprotected' )
1909                                         || $this->mCascadeRestriction )
1910                                 {
1911                                         $errors[] = array( 'protectedpagetext', $right );
1912                                 }
1913                         }
1914                 }
1915
1916                 return $errors;
1917         }
1918
1919         /**
1920          * Check restrictions on cascading pages.
1921          *
1922          * @param $action String the action to check
1923          * @param $user User to check
1924          * @param $errors Array list of current errors
1925          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1926          * @param $short Boolean short circuit on first error
1927          *
1928          * @return Array list of errors
1929          */
1930         private function checkCascadingSourcesRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1931                 if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1932                         # We /could/ use the protection level on the source page, but it's
1933                         # fairly ugly as we have to establish a precedence hierarchy for pages
1934                         # included by multiple cascade-protected pages. So just restrict
1935                         # it to people with 'protect' permission, as they could remove the
1936                         # protection anyway.
1937                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1938                         # Cascading protection depends on more than this page...
1939                         # Several cascading protected pages may include this page...
1940                         # Check each cascading level
1941                         # This is only for protection restrictions, not for all actions
1942                         if ( isset( $restrictions[$action] ) ) {
1943                                 foreach ( $restrictions[$action] as $right ) {
1944                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1945                                         if ( $right != '' && !$user->isAllowed( $right ) ) {
1946                                                 $pages = '';
1947                                                 foreach ( $cascadingSources as $page )
1948                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1949                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1950                                         }
1951                                 }
1952                         }
1953                 }
1954
1955                 return $errors;
1956         }
1957
1958         /**
1959          * Check action permissions not already checked in checkQuickPermissions
1960          *
1961          * @param $action String the action to check
1962          * @param $user User to check
1963          * @param $errors Array list of current errors
1964          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
1965          * @param $short Boolean short circuit on first error
1966          *
1967          * @return Array list of errors
1968          */
1969         private function checkActionPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
1970                 global $wgDeleteRevisionsLimit, $wgLang;
1971
1972                 if ( $action == 'protect' ) {
1973                         if ( count( $this->getUserPermissionsErrorsInternal( 'edit', $user, $doExpensiveQueries, true ) ) ) {
1974                                 // If they can't edit, they shouldn't protect.
1975                                 $errors[] = array( 'protect-cantedit' );
1976                         }
1977                 } elseif ( $action == 'create' ) {
1978                         $title_protection = $this->getTitleProtection();
1979                         if( $title_protection ) {
1980                                 if( $title_protection['pt_create_perm'] == 'sysop' ) {
1981                                         $title_protection['pt_create_perm'] = 'protect'; // B/C
1982                                 }
1983                                 if( $title_protection['pt_create_perm'] == '' ||
1984                                         !$user->isAllowed( $title_protection['pt_create_perm'] ) )
1985                                 {
1986                                         $errors[] = array( 'titleprotected', User::whoIs( $title_protection['pt_user'] ), $title_protection['pt_reason'] );
1987                                 }
1988                         }
1989                 } elseif ( $action == 'move' ) {
1990                         // Check for immobile pages
1991                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
1992                                 // Specific message for this case
1993                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1994                         } elseif ( !$this->isMovable() ) {
1995                                 // Less specific message for rarer cases
1996                                 $errors[] = array( 'immobile-source-page' );
1997                         }
1998                 } elseif ( $action == 'move-target' ) {
1999                         if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
2000                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
2001                         } elseif ( !$this->isMovable() ) {
2002                                 $errors[] = array( 'immobile-target-page' );
2003                         }
2004                 } elseif ( $action == 'delete' ) {
2005                         if ( $doExpensiveQueries && $wgDeleteRevisionsLimit
2006                                 && !$this->userCan( 'bigdelete', $user ) && $this->isBigDeletion() )
2007                         {
2008                                 $errors[] = array( 'delete-toobig', $wgLang->formatNum( $wgDeleteRevisionsLimit ) );
2009                         }
2010                 }
2011                 return $errors;
2012         }
2013
2014         /**
2015          * Check that the user isn't blocked from editting.
2016          *
2017          * @param $action String the action to check
2018          * @param $user User to check
2019          * @param $errors Array list of current errors
2020          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
2021          * @param $short Boolean short circuit on first error
2022          *
2023          * @return Array list of errors
2024          */
2025         private function checkUserBlock( $action, $user, $errors, $doExpensiveQueries, $short ) {
2026                 // Account creation blocks handled at userlogin.
2027                 // Unblocking handled in SpecialUnblock
2028                 if( !$doExpensiveQueries || in_array( $action, array( 'createaccount', 'unblock' ) ) ) {
2029                         return $errors;
2030                 }
2031
2032                 global $wgContLang, $wgLang, $wgEmailConfirmToEdit;
2033
2034                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() ) {
2035                         $errors[] = array( 'confirmedittext' );
2036                 }
2037
2038                 if ( ( $action == 'edit' || $action == 'create' ) && !$user->isBlockedFrom( $this ) ) {
2039                         // Don't block the user from editing their own talk page unless they've been
2040                         // explicitly blocked from that too.
2041                 } elseif( $user->isBlocked() && $user->mBlock->prevents( $action ) !== false ) {
2042                         $block = $user->getBlock();
2043
2044                         // This is from OutputPage::blockedPage
2045                         // Copied at r23888 by werdna
2046
2047                         $id = $user->blockedBy();
2048                         $reason = $user->blockedFor();
2049                         if ( $reason == '' ) {
2050                                 $reason = wfMessage( 'blockednoreason' )->text();
2051                         }
2052                         $ip = $user->getRequest()->getIP();
2053
2054                         if ( is_numeric( $id ) ) {
2055                                 $name = User::whoIs( $id );
2056                         } else {
2057                                 $name = $id;
2058                         }
2059
2060                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
2061                         $blockid = $block->getId();
2062                         $blockExpiry = $block->getExpiry();
2063                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $block->mTimestamp ), true );
2064                         if ( $blockExpiry == 'infinity' ) {
2065                                 $blockExpiry = wfMessage( 'infiniteblock' )->text();
2066                         } else {
2067                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
2068                         }
2069
2070                         $intended = strval( $block->getTarget() );
2071
2072                         $errors[] = array( ( $block->mAuto ? 'autoblockedtext' : 'blockedtext' ), $link, $reason, $ip, $name,
2073                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
2074                 }
2075
2076                 return $errors;
2077         }
2078
2079         /**
2080          * Check that the user is allowed to read this page.
2081          *
2082          * @param $action String the action to check
2083          * @param $user User to check
2084          * @param $errors Array list of current errors
2085          * @param $doExpensiveQueries Boolean whether or not to perform expensive queries
2086          * @param $short Boolean short circuit on first error
2087          *
2088          * @return Array list of errors
2089          */
2090         private function checkReadPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
2091                 global $wgWhitelistRead, $wgWhitelistReadRegexp, $wgRevokePermissions;
2092                 static $useShortcut = null;
2093
2094                 # Initialize the $useShortcut boolean, to determine if we can skip quite a bit of code below
2095                 if ( is_null( $useShortcut ) ) {
2096                         $useShortcut = true;
2097                         if ( !User::groupHasPermission( '*', 'read' ) ) {
2098                                 # Not a public wiki, so no shortcut
2099                                 $useShortcut = false;
2100                         } elseif ( !empty( $wgRevokePermissions ) ) {
2101                                 /**
2102                                  * Iterate through each group with permissions being revoked (key not included since we don't care
2103                                  * what the group name is), then check if the read permission is being revoked. If it is, then
2104                                  * we don't use the shortcut below since the user might not be able to read, even though anon
2105                                  * reading is allowed.
2106                                  */
2107                                 foreach ( $wgRevokePermissions as $perms ) {
2108                                         if ( !empty( $perms['read'] ) ) {
2109                                                 # We might be removing the read right from the user, so no shortcut
2110                                                 $useShortcut = false;
2111                                                 break;
2112                                         }
2113                                 }
2114                         }
2115                 }
2116
2117                 $whitelisted = false;
2118                 if ( $useShortcut ) {
2119                         # Shortcut for public wikis, allows skipping quite a bit of code
2120                         $whitelisted = true;
2121                 } elseif ( $user->isAllowed( 'read' ) ) {
2122                         # If the user is allowed to read pages, he is allowed to read all pages
2123                         $whitelisted = true;
2124                 } elseif ( $this->isSpecial( 'Userlogin' )
2125                         || $this->isSpecial( 'ChangePassword' )
2126                         || $this->isSpecial( 'PasswordReset' )
2127                 ) {
2128                         # Always grant access to the login page.
2129                         # Even anons need to be able to log in.
2130                         $whitelisted = true;
2131                 } elseif ( is_array( $wgWhitelistRead ) && count( $wgWhitelistRead ) ) {
2132                         # Time to check the whitelist
2133                         # Only do these checks is there's something to check against
2134                         $name = $this->getPrefixedText();
2135                         $dbName = $this->getPrefixedDBKey();
2136
2137                         // Check for explicit whitelisting with and without underscores
2138                         if ( in_array( $name, $wgWhitelistRead, true ) || in_array( $dbName, $wgWhitelistRead, true ) ) {
2139                                 $whitelisted = true;
2140                         } elseif ( $this->getNamespace() == NS_MAIN ) {
2141                                 # Old settings might have the title prefixed with
2142                                 # a colon for main-namespace pages
2143                                 if ( in_array( ':' . $name, $wgWhitelistRead ) ) {
2144                                         $whitelisted = true;
2145                                 }
2146                         } elseif ( $this->isSpecialPage() ) {
2147                                 # If it's a special page, ditch the subpage bit and check again
2148                                 $name = $this->getDBkey();
2149                                 list( $name, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $name );
2150                                 if ( $name ) {
2151                                         $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
2152                                         if ( in_array( $pure, $wgWhitelistRead, true ) ) {
2153                                                 $whitelisted = true;
2154                                         }
2155                                 }
2156                         }
2157                 }
2158
2159                 if( !$whitelisted && is_array( $wgWhitelistReadRegexp ) && !empty( $wgWhitelistReadRegexp ) ) {
2160                         $name = $this->getPrefixedText();
2161                         // Check for regex whitelisting
2162                         foreach ( $wgWhitelistReadRegexp as $listItem ) {
2163                                 if ( preg_match( $listItem, $name ) ) {
2164                                         $whitelisted = true;
2165                                         break;
2166                                 }
2167                         }
2168                 }
2169
2170                 if ( !$whitelisted ) {
2171                         # If the title is not whitelisted, give extensions a chance to do so...
2172                         wfRunHooks( 'TitleReadWhitelist', array( $this, $user, &$whitelisted ) );
2173                         if ( !$whitelisted ) {
2174                                 $errors[] = $this->missingPermissionError( $action, $short );
2175                         }
2176                 }
2177
2178                 return $errors;
2179         }
2180
2181         /**
2182          * Get a description array when the user doesn't have the right to perform
2183          * $action (i.e. when User::isAllowed() returns false)
2184          *
2185          * @param $action String the action to check
2186          * @param $short Boolean short circuit on first error
2187          * @return Array list of errors
2188          */
2189         private function missingPermissionError( $action, $short ) {
2190                 // We avoid expensive display logic for quickUserCan's and such
2191                 if ( $short ) {
2192                         return array( 'badaccess-group0' );
2193                 }
2194
2195                 $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
2196                         User::getGroupsWithPermission( $action ) );
2197
2198                 if ( count( $groups ) ) {
2199                         global $wgLang;
2200                         return array(
2201                                 'badaccess-groups',
2202                                 $wgLang->commaList( $groups ),
2203                                 count( $groups )
2204                         );
2205                 } else {
2206                         return array( 'badaccess-group0' );
2207                 }
2208         }
2209
2210         /**
2211          * Can $user perform $action on this page? This is an internal function,
2212          * which checks ONLY that previously checked by userCan (i.e. it leaves out
2213          * checks on wfReadOnly() and blocks)
2214          *
2215          * @param $action String action that permission needs to be checked for
2216          * @param $user User to check
2217          * @param $doExpensiveQueries Bool Set this to false to avoid doing unnecessary queries.
2218          * @param $short Bool Set this to true to stop after the first permission error.
2219          * @return Array of arrays of the arguments to wfMessage to explain permissions problems.
2220          */
2221         protected function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries = true, $short = false ) {
2222                 wfProfileIn( __METHOD__ );
2223
2224                 # Read has special handling
2225                 if ( $action == 'read' ) {
2226                         $checks = array(
2227                                 'checkPermissionHooks',
2228                                 'checkReadPermissions',
2229                         );
2230                 } else {
2231                         $checks = array(
2232                                 'checkQuickPermissions',
2233                                 'checkPermissionHooks',
2234                                 'checkSpecialsAndNSPermissions',
2235                                 'checkCSSandJSPermissions',
2236                                 'checkPageRestrictions',
2237                                 'checkCascadingSourcesRestrictions',
2238                                 'checkActionPermissions',
2239                                 'checkUserBlock'
2240                         );
2241                 }
2242
2243                 $errors = array();
2244                 while( count( $checks ) > 0 &&
2245                                 !( $short && count( $errors ) > 0 ) ) {
2246                         $method = array_shift( $checks );
2247                         $errors = $this->$method( $action, $user, $errors, $doExpensiveQueries, $short );
2248                 }
2249
2250                 wfProfileOut( __METHOD__ );
2251                 return $errors;
2252         }
2253
2254         /**
2255          * Protect css subpages of user pages: can $wgUser edit
2256          * this page?
2257          *
2258          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2259          * @return Bool
2260          */
2261         public function userCanEditCssSubpage() {
2262                 global $wgUser;
2263                 wfDeprecated( __METHOD__, '1.19' );
2264                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'editusercss' ) )
2265                         || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2266         }
2267
2268         /**
2269          * Protect js subpages of user pages: can $wgUser edit
2270          * this page?
2271          *
2272          * @deprecated in 1.19; will be removed in 1.20. Use getUserPermissionsErrors() instead.
2273          * @return Bool
2274          */
2275         public function userCanEditJsSubpage() {
2276                 global $wgUser;
2277                 wfDeprecated( __METHOD__, '1.19' );
2278                 return ( ( $wgUser->isAllowedAll( 'editusercssjs', 'edituserjs' ) )
2279                            || preg_match( '/^' . preg_quote( $wgUser->getName(), '/' ) . '\//', $this->mTextform ) );
2280         }
2281
2282         /**
2283          * Get a filtered list of all restriction types supported by this wiki.
2284          * @param bool $exists True to get all restriction types that apply to
2285          * titles that do exist, False for all restriction types that apply to
2286          * titles that do not exist
2287          * @return array
2288          */
2289         public static function getFilteredRestrictionTypes( $exists = true ) {
2290                 global $wgRestrictionTypes;
2291                 $types = $wgRestrictionTypes;
2292                 if ( $exists ) {
2293                         # Remove the create restriction for existing titles
2294                         $types = array_diff( $types, array( 'create' ) );
2295                 } else {
2296                         # Only the create and upload restrictions apply to non-existing titles
2297                         $types = array_intersect( $types, array( 'create', 'upload' ) );
2298                 }
2299                 return $types;
2300         }
2301
2302         /**
2303          * Returns restriction types for the current Title
2304          *
2305          * @return array applicable restriction types
2306          */
2307         public function getRestrictionTypes() {
2308                 if ( $this->isSpecialPage() ) {
2309                         return array();
2310                 }
2311
2312                 $types = self::getFilteredRestrictionTypes( $this->exists() );
2313
2314                 if ( $this->getNamespace() != NS_FILE ) {
2315                         # Remove the upload restriction for non-file titles
2316                         $types = array_diff( $types, array( 'upload' ) );
2317                 }
2318
2319                 wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );
2320
2321                 wfDebug( __METHOD__ . ': applicable restrictions to [[' .
2322                         $this->getPrefixedText() . ']] are {' . implode( ',', $types ) . "}\n" );
2323
2324                 return $types;
2325         }
2326
2327         /**
2328          * Is this title subject to title protection?
2329          * Title protection is the one applied against creation of such title.
2330          *
2331          * @return Mixed An associative array representing any existent title
2332          *   protection, or false if there's none.
2333          */
2334         private function getTitleProtection() {
2335                 // Can't protect pages in special namespaces
2336                 if ( $this->getNamespace() < 0 ) {
2337                         return false;
2338                 }
2339
2340                 // Can't protect pages that exist.
2341                 if ( $this->exists() ) {
2342                         return false;
2343                 }
2344
2345                 if ( !isset( $this->mTitleProtection ) ) {
2346                         $dbr = wfGetDB( DB_SLAVE );
2347                         $res = $dbr->select(
2348                                 'protected_titles',
2349                                 array( 'pt_user', 'pt_reason', 'pt_expiry', 'pt_create_perm' ),
2350                                 array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2351                                 __METHOD__
2352                         );
2353
2354                         // fetchRow returns false if there are no rows.
2355                         $this->mTitleProtection = $dbr->fetchRow( $res );
2356                 }
2357                 return $this->mTitleProtection;
2358         }
2359
2360         /**
2361          * Update the title protection status
2362          *
2363          * @deprecated in 1.19; will be removed in 1.20. Use WikiPage::doUpdateRestrictions() instead.
2364          * @param $create_perm String Permission required for creation
2365          * @param $reason String Reason for protection
2366          * @param $expiry String Expiry timestamp
2367          * @return boolean true
2368          */
2369         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
2370                 wfDeprecated( __METHOD__, '1.19' );
2371
2372                 global $wgUser;
2373
2374                 $limit = array( 'create' => $create_perm );
2375                 $expiry = array( 'create' => $expiry );
2376
2377                 $page = WikiPage::factory( $this );
2378                 $cascade = false;
2379                 $status = $page->doUpdateRestrictions( $limit, $expiry, $cascade, $reason, $wgUser );
2380
2381                 return $status->isOK();
2382         }
2383
2384         /**
2385          * Remove any title protection due to page existing
2386          */
2387         public function deleteTitleProtection() {
2388                 $dbw = wfGetDB( DB_MASTER );
2389
2390                 $dbw->delete(
2391                         'protected_titles',
2392                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
2393                         __METHOD__
2394                 );
2395                 $this->mTitleProtection = false;
2396         }
2397
2398         /**
2399          * Is this page "semi-protected" - the *only* protection is autoconfirm?
2400          *
2401          * @param $action String Action to check (default: edit)
2402          * @return Bool
2403          */
2404         public function isSemiProtected( $action = 'edit' ) {
2405                 if ( $this->exists() ) {
2406                         $restrictions = $this->getRestrictions( $action );
2407                         if ( count( $restrictions ) > 0 ) {
2408                                 foreach ( $restrictions as $restriction ) {
2409                                         if ( strtolower( $restriction ) != 'autoconfirmed' ) {
2410                                                 return false;
2411                                         }
2412                                 }
2413                         } else {
2414                                 # Not protected
2415                                 return false;
2416                         }
2417                         return true;
2418                 } else {
2419                         # If it doesn't exist, it can't be protected
2420                         return false;
2421                 }
2422         }
2423
2424         /**
2425          * Does the title correspond to a protected article?
2426          *
2427          * @param $action String the action the page is protected from,
2428          * by default checks all actions.
2429          * @return Bool
2430          */
2431         public function isProtected( $action = '' ) {
2432                 global $wgRestrictionLevels;
2433
2434                 $restrictionTypes = $this->getRestrictionTypes();
2435
2436                 # Special pages have inherent protection
2437                 if( $this->isSpecialPage() ) {
2438                         return true;
2439                 }
2440
2441                 # Check regular protection levels
2442                 foreach ( $restrictionTypes as $type ) {
2443                         if ( $action == $type || $action == '' ) {
2444                                 $r = $this->getRestrictions( $type );
2445                                 foreach ( $wgRestrictionLevels as $level ) {
2446                                         if ( in_array( $level, $r ) && $level != '' ) {
2447                                                 return true;
2448                                         }
2449                                 }
2450                         }
2451                 }
2452
2453                 return false;
2454         }
2455
2456         /**
2457          * Determines if $user is unable to edit this page because it has been protected
2458          * by $wgNamespaceProtection.
2459          *
2460          * @param $user User object to check permissions
2461          * @return Bool
2462          */
2463         public function isNamespaceProtected( User $user ) {
2464                 global $wgNamespaceProtection;
2465
2466                 if ( isset( $wgNamespaceProtection[$this->mNamespace] ) ) {
2467                         foreach ( (array)$wgNamespaceProtection[$this->mNamespace] as $right ) {
2468                                 if ( $right != '' && !$user->isAllowed( $right ) ) {
2469                                         return true;
2470                                 }
2471                         }
2472                 }
2473                 return false;
2474         }
2475
2476         /**
2477          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
2478          *
2479          * @return Bool If the page is subject to cascading restrictions.
2480          */
2481         public function isCascadeProtected() {
2482                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
2483                 return ( $sources > 0 );
2484         }
2485
2486         /**
2487          * Cascading protection: Get the source of any cascading restrictions on this page.
2488          *
2489          * @param $getPages Bool Whether or not to retrieve the actual pages
2490          *        that the restrictions have come from.
2491          * @return Mixed Array of Title objects of the pages from which cascading restrictions
2492          *     have come, false for none, or true if such restrictions exist, but $getPages
2493          *     was not set.  The restriction array is an array of each type, each of which
2494          *     contains a array of unique groups.
2495          */
2496         public function getCascadeProtectionSources( $getPages = true ) {
2497                 global $wgContLang;
2498                 $pagerestrictions = array();
2499
2500                 if ( isset( $this->mCascadeSources ) && $getPages ) {
2501                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
2502                 } elseif ( isset( $this->mHasCascadingRestrictions ) && !$getPages ) {
2503                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
2504                 }
2505
2506                 wfProfileIn( __METHOD__ );
2507
2508                 $dbr = wfGetDB( DB_SLAVE );
2509
2510                 if ( $this->getNamespace() == NS_FILE ) {
2511                         $tables = array( 'imagelinks', 'page_restrictions' );
2512                         $where_clauses = array(
2513                                 'il_to' => $this->getDBkey(),
2514                                 'il_from=pr_page',
2515                                 'pr_cascade' => 1
2516                         );
2517                 } else {
2518                         $tables = array( 'templatelinks', 'page_restrictions' );
2519                         $where_clauses = array(
2520                                 'tl_namespace' => $this->getNamespace(),
2521                                 'tl_title' => $this->getDBkey(),
2522                                 'tl_from=pr_page',
2523                                 'pr_cascade' => 1
2524                         );
2525                 }
2526
2527                 if ( $getPages ) {
2528                         $cols = array( 'pr_page', 'page_namespace', 'page_title',
2529                                                    'pr_expiry', 'pr_type', 'pr_level' );
2530                         $where_clauses[] = 'page_id=pr_page';
2531                         $tables[] = 'page';
2532                 } else {
2533                         $cols = array( 'pr_expiry' );
2534                 }
2535
2536                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
2537
2538                 $sources = $getPages ? array() : false;
2539                 $now = wfTimestampNow();
2540                 $purgeExpired = false;
2541
2542                 foreach ( $res as $row ) {
2543                         $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2544                         if ( $expiry > $now ) {
2545                                 if ( $getPages ) {
2546                                         $page_id = $row->pr_page;
2547                                         $page_ns = $row->page_namespace;
2548                                         $page_title = $row->page_title;
2549                                         $sources[$page_id] = Title::makeTitle( $page_ns, $page_title );
2550                                         # Add groups needed for each restriction type if its not already there
2551                                         # Make sure this restriction type still exists
2552
2553                                         if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
2554                                                 $pagerestrictions[$row->pr_type] = array();
2555                                         }
2556
2557                                         if ( isset( $pagerestrictions[$row->pr_type] ) &&
2558                                                  !in_array( $row->pr_level, $pagerestrictions[$row->pr_type] ) ) {
2559                                                 $pagerestrictions[$row->pr_type][] = $row->pr_level;
2560                                         }
2561                                 } else {
2562                                         $sources = true;
2563                                 }
2564                         } else {
2565                                 // Trigger lazy purge of expired restrictions from the db
2566                                 $purgeExpired = true;
2567                         }
2568                 }
2569                 if ( $purgeExpired ) {
2570                         Title::purgeExpiredRestrictions();
2571                 }
2572
2573                 if ( $getPages ) {
2574                         $this->mCascadeSources = $sources;
2575                         $this->mCascadingRestrictions = $pagerestrictions;
2576                 } else {
2577                         $this->mHasCascadingRestrictions = $sources;
2578                 }
2579
2580                 wfProfileOut( __METHOD__ );
2581                 return array( $sources, $pagerestrictions );
2582         }
2583
2584         /**
2585          * Accessor/initialisation for mRestrictions
2586          *
2587          * @param $action String action that permission needs to be checked for
2588          * @return Array of Strings the array of groups allowed to edit this article
2589          */
2590         public function getRestrictions( $action ) {
2591                 if ( !$this->mRestrictionsLoaded ) {
2592                         $this->loadRestrictions();
2593                 }
2594                 return isset( $this->mRestrictions[$action] )
2595                                 ? $this->mRestrictions[$action]
2596                                 : array();
2597         }
2598
2599         /**
2600          * Get the expiry time for the restriction against a given action
2601          *
2602          * @param $action
2603          * @return String|Bool 14-char timestamp, or 'infinity' if the page is protected forever
2604          *     or not protected at all, or false if the action is not recognised.
2605          */
2606         public function getRestrictionExpiry( $action ) {
2607                 if ( !$this->mRestrictionsLoaded ) {
2608                         $this->loadRestrictions();
2609                 }
2610                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
2611         }
2612
2613         /**
2614          * Returns cascading restrictions for the current article
2615          *
2616          * @return Boolean
2617          */
2618         function areRestrictionsCascading() {
2619                 if ( !$this->mRestrictionsLoaded ) {
2620                         $this->loadRestrictions();
2621                 }
2622
2623                 return $this->mCascadeRestriction;
2624         }
2625
2626         /**
2627          * Loads a string into mRestrictions array
2628          *
2629          * @param $res Resource restrictions as an SQL result.
2630          * @param $oldFashionedRestrictions String comma-separated list of page
2631          *        restrictions from page table (pre 1.10)
2632          */
2633         private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
2634                 $rows = array();
2635
2636                 foreach ( $res as $row ) {
2637                         $rows[] = $row;
2638                 }
2639
2640                 $this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
2641         }
2642
2643         /**
2644          * Compiles list of active page restrictions from both page table (pre 1.10)
2645          * and page_restrictions table for this existing page.
2646          * Public for usage by LiquidThreads.
2647          *
2648          * @param $rows array of db result objects
2649          * @param $oldFashionedRestrictions string comma-separated list of page
2650          *        restrictions from page table (pre 1.10)
2651          */
2652         public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
2653                 global $wgContLang;
2654                 $dbr = wfGetDB( DB_SLAVE );
2655
2656                 $restrictionTypes = $this->getRestrictionTypes();
2657
2658                 foreach ( $restrictionTypes as $type ) {
2659                         $this->mRestrictions[$type] = array();
2660                         $this->mRestrictionsExpiry[$type] = $wgContLang->formatExpiry( '', TS_MW );
2661                 }
2662
2663                 $this->mCascadeRestriction = false;
2664
2665                 # Backwards-compatibility: also load the restrictions from the page record (old format).
2666
2667                 if ( $oldFashionedRestrictions === null ) {
2668                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
2669                                 array( 'page_id' => $this->getArticleID() ), __METHOD__ );
2670                 }
2671
2672                 if ( $oldFashionedRestrictions != '' ) {
2673
2674                         foreach ( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
2675                                 $temp = explode( '=', trim( $restrict ) );
2676                                 if ( count( $temp ) == 1 ) {
2677                                         // old old format should be treated as edit/move restriction
2678                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
2679                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
2680                                 } else {
2681                                         $restriction = trim( $temp[1] );
2682                                         if( $restriction != '' ) { //some old entries are empty
2683                                                 $this->mRestrictions[$temp[0]] = explode( ',', $restriction );
2684                                         }
2685                                 }
2686                         }
2687
2688                         $this->mOldRestrictions = true;
2689
2690                 }
2691
2692                 if ( count( $rows ) ) {
2693                         # Current system - load second to make them override.
2694                         $now = wfTimestampNow();
2695                         $purgeExpired = false;
2696
2697                         # Cycle through all the restrictions.
2698                         foreach ( $rows as $row ) {
2699
2700                                 // Don't take care of restrictions types that aren't allowed
2701                                 if ( !in_array( $row->pr_type, $restrictionTypes ) )
2702                                         continue;
2703
2704                                 // This code should be refactored, now that it's being used more generally,
2705                                 // But I don't really see any harm in leaving it in Block for now -werdna
2706                                 $expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
2707
2708                                 // Only apply the restrictions if they haven't expired!
2709                                 if ( !$expiry || $expiry > $now ) {
2710                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
2711                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
2712
2713                                         $this->mCascadeRestriction |= $row->pr_cascade;
2714                                 } else {
2715                                         // Trigger a lazy purge of expired restrictions
2716                                         $purgeExpired = true;
2717                                 }
2718                         }
2719
2720                         if ( $purgeExpired ) {
2721                                 Title::purgeExpiredRestrictions();
2722                         }
2723                 }
2724
2725                 $this->mRestrictionsLoaded = true;
2726         }
2727
2728         /**
2729          * Load restrictions from the page_restrictions table
2730          *
2731          * @param $oldFashionedRestrictions String comma-separated list of page
2732          *        restrictions from page table (pre 1.10)
2733          */
2734         public function loadRestrictions( $oldFashionedRestrictions = null ) {
2735                 global $wgContLang;
2736                 if ( !$this->mRestrictionsLoaded ) {
2737                         if ( $this->exists() ) {
2738                                 $dbr = wfGetDB( DB_SLAVE );
2739
2740                                 $res = $dbr->select(
2741                                         'page_restrictions',
2742                                         array( 'pr_type', 'pr_expiry', 'pr_level', 'pr_cascade' ),
2743                                         array( 'pr_page' => $this->getArticleID() ),
2744                                         __METHOD__
2745                                 );
2746
2747                                 $this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
2748                         } else {
2749                                 $title_protection = $this->getTitleProtection();
2750
2751                                 if ( $title_protection ) {
2752                                         $now = wfTimestampNow();
2753                                         $expiry = $wgContLang->formatExpiry( $title_protection['pt_expiry'], TS_MW );
2754
2755                                         if ( !$expiry || $expiry > $now ) {
2756                                                 // Apply the restrictions
2757                                                 $this->mRestrictionsExpiry['create'] = $expiry;
2758                                                 $this->mRestrictions['create'] = explode( ',', trim( $title_protection['pt_create_perm'] ) );
2759                                         } else { // Get rid of the old restrictions
2760                                                 Title::purgeExpiredRestrictions();
2761                                                 $this->mTitleProtection = false;
2762                                         }
2763                                 } else {
2764                                         $this->mRestrictionsExpiry['create'] = $wgContLang->formatExpiry( '', TS_MW );
2765                                 }
2766                                 $this->mRestrictionsLoaded = true;
2767                         }
2768                 }
2769         }
2770
2771         /**
2772          * Flush the protection cache in this object and force reload from the database.
2773          * This is used when updating protection from WikiPage::doUpdateRestrictions().
2774          */
2775         public function flushRestrictions() {
2776                 $this->mRestrictionsLoaded = false;
2777                 $this->mTitleProtection = null;
2778         }
2779
2780         /**
2781          * Purge expired restrictions from the page_restrictions table
2782          */
2783         static function purgeExpiredRestrictions() {
2784                 if ( wfReadOnly() ) {
2785                         return;
2786                 }
2787
2788                 $dbw = wfGetDB( DB_MASTER );
2789                 $dbw->delete(
2790                         'page_restrictions',
2791                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2792                         __METHOD__
2793                 );
2794
2795                 $dbw->delete(
2796                         'protected_titles',
2797                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
2798                         __METHOD__
2799                 );
2800         }
2801
2802         /**
2803          * Does this have subpages?  (Warning, usually requires an extra DB query.)
2804          *
2805          * @return Bool
2806          */
2807         public function hasSubpages() {
2808                 if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
2809                         # Duh
2810                         return false;
2811                 }
2812
2813                 # We dynamically add a member variable for the purpose of this method
2814                 # alone to cache the result.  There's no point in having it hanging
2815                 # around uninitialized in every Title object; therefore we only add it
2816                 # if needed and don't declare it statically.
2817                 if ( isset( $this->mHasSubpages ) ) {
2818                         return $this->mHasSubpages;
2819                 }
2820
2821                 $subpages = $this->getSubpages( 1 );
2822                 if ( $subpages instanceof TitleArray ) {
2823                         return $this->mHasSubpages = (bool)$subpages->count();
2824                 }
2825                 return $this->mHasSubpages = false;
2826         }
2827
2828         /**
2829          * Get all subpages of this page.
2830          *
2831          * @param $limit Int maximum number of subpages to fetch; -1 for no limit
2832          * @return mixed TitleArray, or empty array if this page's namespace
2833          *  doesn't allow subpages
2834          */
2835         public function getSubpages( $limit = -1 ) {
2836                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
2837                         return array();
2838                 }
2839
2840                 $dbr = wfGetDB( DB_SLAVE );
2841                 $conds['page_namespace'] = $this->getNamespace();
2842                 $conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
2843                 $options = array();
2844                 if ( $limit > -1 ) {
2845                         $options['LIMIT'] = $limit;
2846                 }
2847                 return $this->mSubpages = TitleArray::newFromResult(
2848                         $dbr->select( 'page',
2849                                 array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
2850                                 $conds,
2851                                 __METHOD__,
2852                                 $options
2853                         )
2854                 );
2855         }
2856
2857         /**
2858          * Is there a version of this page in the deletion archive?
2859          *
2860          * @return Int the number of archived revisions
2861          */
2862         public function isDeleted() {
2863                 if ( $this->getNamespace() < 0 ) {
2864                         $n = 0;
2865                 } else {
2866                         $dbr = wfGetDB( DB_SLAVE );
2867
2868                         $n = $dbr->selectField( 'archive', 'COUNT(*)',
2869                                 array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2870                                 __METHOD__
2871                         );
2872                         if ( $this->getNamespace() == NS_FILE ) {
2873                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
2874                                         array( 'fa_name' => $this->getDBkey() ),
2875                                         __METHOD__
2876                                 );
2877                         }
2878                 }
2879                 return (int)$n;
2880         }
2881
2882         /**
2883          * Is there a version of this page in the deletion archive?
2884          *
2885          * @return Boolean
2886          */
2887         public function isDeletedQuick() {
2888                 if ( $this->getNamespace() < 0 ) {
2889                         return false;
2890                 }
2891                 $dbr = wfGetDB( DB_SLAVE );
2892                 $deleted = (bool)$dbr->selectField( 'archive', '1',
2893                         array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
2894                         __METHOD__
2895                 );
2896                 if ( !$deleted && $this->getNamespace() == NS_FILE ) {
2897                         $deleted = (bool)$dbr->selectField( 'filearchive', '1',
2898                                 array( 'fa_name' => $this->getDBkey() ),
2899                                 __METHOD__
2900                         );
2901                 }
2902                 return $deleted;
2903         }
2904
2905         /**
2906          * Get the article ID for this Title from the link cache,
2907          * adding it if necessary
2908          *
2909          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select
2910          *  for update
2911          * @return Int the ID
2912          */
2913         public function getArticleID( $flags = 0 ) {
2914                 if ( $this->getNamespace() < 0 ) {
2915                         return $this->mArticleID = 0;
2916                 }
2917                 $linkCache = LinkCache::singleton();
2918                 if ( $flags & self::GAID_FOR_UPDATE ) {
2919                         $oldUpdate = $linkCache->forUpdate( true );
2920                         $linkCache->clearLink( $this );
2921                         $this->mArticleID = $linkCache->addLinkObj( $this );
2922                         $linkCache->forUpdate( $oldUpdate );
2923                 } else {
2924                         if ( -1 == $this->mArticleID ) {
2925                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2926                         }
2927                 }
2928                 return $this->mArticleID;
2929         }
2930
2931         /**
2932          * Is this an article that is a redirect page?
2933          * Uses link cache, adding it if necessary
2934          *
2935          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2936          * @return Bool
2937          */
2938         public function isRedirect( $flags = 0 ) {
2939                 if ( !( $flags & Title::GAID_FOR_UPDATE ) && !is_null( $this->mRedirect ) ) {
2940                         return $this->mRedirect;
2941                 }
2942
2943                 if ( !$this->getArticleID( $flags ) ) {
2944                         return $this->mRedirect = false;
2945                 }
2946
2947                 $linkCache = LinkCache::singleton();
2948                 $linkCache->addLinkObj( $this );
2949                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2950
2951                 if ( $cached === null ) {
2952                         // Should not happen
2953                         throw new MWException( "LinkCache doesn't know redirect status of this title: " . $this->getPrefixedDBkey() );
2954                 }
2955
2956                 $this->mRedirect = (bool)$cached;
2957
2958                 return $this->mRedirect;
2959         }
2960
2961         /**
2962          * What is the length of this page?
2963          * Uses link cache, adding it if necessary
2964          *
2965          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2966          * @return Int
2967          */
2968         public function getLength( $flags = 0 ) {
2969                 if ( !( $flags & Title::GAID_FOR_UPDATE ) && $this->mLength != -1 ) {
2970                         return $this->mLength;
2971                 }
2972
2973                 if ( !$this->getArticleID( $flags ) ) {
2974                         return $this->mLength = 0;
2975                 }
2976
2977                 $linkCache = LinkCache::singleton();
2978                 $linkCache->addLinkObj( $this );
2979                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'length' );
2980
2981                 if ( $cached === null ) {
2982                         // Should not happen
2983                         throw new MWException( "LinkCache doesn't know redirect status of this title: " . $this->getPrefixedDBkey() );
2984                 }
2985
2986                 $this->mLength = intval( $cached );
2987
2988                 return $this->mLength;
2989         }
2990
2991         /**
2992          * What is the page_latest field for this page?
2993          *
2994          * @param $flags Int a bit field; may be Title::GAID_FOR_UPDATE to select for update
2995          * @throws MWException
2996          * @return Int or 0 if the page doesn't exist
2997          */
2998         public function getLatestRevID( $flags = 0 ) {
2999                 if ( !( $flags & Title::GAID_FOR_UPDATE ) && $this->mLatestID !== false ) {
3000                         return intval( $this->mLatestID );
3001                 }
3002
3003                 if ( !$this->getArticleID( $flags ) ) {
3004                         return $this->mLatestID = 0;
3005                 }
3006
3007                 $linkCache = LinkCache::singleton();
3008                 $linkCache->addLinkObj( $this );
3009                 $cached = $linkCache->getGoodLinkFieldObj( $this, 'revision' );
3010
3011                 if ( $cached === null ) {
3012                         // Should not happen
3013                         throw new MWException( "LinkCache doesn't know latest revision ID of this title: " . $this->getPrefixedDBkey() );
3014                 }
3015
3016                 $this->mLatestID = intval( $cached );
3017
3018                 return $this->mLatestID;
3019         }
3020
3021         /**
3022          * This clears some fields in this object, and clears any associated
3023          * keys in the "bad links" section of the link cache.
3024          *
3025          * - This is called from WikiPage::doEdit() and WikiPage::insertOn() to allow
3026          * loading of the new page_id. It's also called from
3027          * WikiPage::doDeleteArticleReal()
3028          *
3029          * @param $newid Int the new Article ID
3030          */
3031         public function resetArticleID( $newid ) {
3032                 $linkCache = LinkCache::singleton();
3033                 $linkCache->clearLink( $this );
3034
3035                 if ( $newid === false ) {
3036                         $this->mArticleID = -1;
3037                 } else {
3038                         $this->mArticleID = intval( $newid );
3039                 }
3040                 $this->mRestrictionsLoaded = false;
3041                 $this->mRestrictions = array();
3042                 $this->mRedirect = null;
3043                 $this->mLength = -1;
3044                 $this->mLatestID = false;
3045                 $this->mContentModel = false;
3046                 $this->mEstimateRevisions = null;
3047         }
3048
3049         /**
3050          * Capitalize a text string for a title if it belongs to a namespace that capitalizes
3051          *
3052          * @param $text String containing title to capitalize
3053          * @param $ns int namespace index, defaults to NS_MAIN
3054          * @return String containing capitalized title
3055          */
3056         public static function capitalize( $text, $ns = NS_MAIN ) {
3057                 global $wgContLang;
3058
3059                 if ( MWNamespace::isCapitalized( $ns ) ) {
3060                         return $wgContLang->ucfirst( $text );
3061                 } else {
3062                         return $text;
3063                 }
3064         }
3065
3066         /**
3067          * Secure and split - main initialisation function for this object
3068          *
3069          * Assumes that mDbkeyform has been set, and is urldecoded
3070          * and uses underscores, but not otherwise munged.  This function
3071          * removes illegal characters, splits off the interwiki and
3072          * namespace prefixes, sets the other forms, and canonicalizes
3073          * everything.
3074          *
3075          * @return Bool true on success
3076          */
3077         private function secureAndSplit() {
3078                 global $wgContLang, $wgLocalInterwiki;
3079
3080                 # Initialisation
3081                 $this->mInterwiki = $this->mFragment = '';
3082                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
3083
3084                 $dbkey = $this->mDbkeyform;
3085
3086                 # Strip Unicode bidi override characters.
3087                 # Sometimes they slip into cut-n-pasted page titles, where the
3088                 # override chars get included in list displays.
3089                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
3090
3091                 # Clean up whitespace
3092                 # Note: use of the /u option on preg_replace here will cause
3093                 # input with invalid UTF-8 sequences to be nullified out in PHP 5.2.x,
3094                 # conveniently disabling them.
3095                 $dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
3096                 $dbkey = trim( $dbkey, '_' );
3097
3098                 if ( $dbkey == '' ) {
3099                         return false;
3100                 }
3101
3102                 if ( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
3103                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
3104                         return false;
3105                 }
3106
3107                 $this->mDbkeyform = $dbkey;
3108
3109                 # Initial colon indicates main namespace rather than specified default
3110                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
3111                 if ( ':' == $dbkey[0] ) {
3112                         $this->mNamespace = NS_MAIN;
3113                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
3114                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
3115                 }
3116
3117                 # Namespace or interwiki prefix
3118                 $firstPass = true;
3119                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
3120                 do {
3121                         $m = array();
3122                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
3123                                 $p = $m[1];
3124                                 if ( ( $ns = $wgContLang->getNsIndex( $p ) ) !== false ) {
3125                                         # Ordinary namespace
3126                                         $dbkey = $m[2];
3127                                         $this->mNamespace = $ns;
3128                                         # For Talk:X pages, check if X has a "namespace" prefix
3129                                         if ( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
3130                                                 if ( $wgContLang->getNsIndex( $x[1] ) ) {
3131                                                         # Disallow Talk:File:x type titles...
3132                                                         return false;
3133                                                 } elseif ( Interwiki::isValidInterwiki( $x[1] ) ) {
3134                                                         # Disallow Talk:Interwiki:x type titles...
3135                                                         return false;
3136                                                 }
3137                                         }
3138                                 } elseif ( Interwiki::isValidInterwiki( $p ) ) {
3139                                         if ( !$firstPass ) {
3140                                                 # Can't make a local interwiki link to an interwiki link.
3141                                                 # That's just crazy!
3142                                                 return false;
3143                                         }
3144
3145                                         # Interwiki link
3146                                         $dbkey = $m[2];
3147                                         $this->mInterwiki = $wgContLang->lc( $p );
3148
3149                                         # Redundant interwiki prefix to the local wiki
3150                                         if ( $wgLocalInterwiki !== false
3151                                                 && 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) )
3152                                         {
3153                                                 if ( $dbkey == '' ) {
3154                                                         # Can't have an empty self-link
3155                                                         return false;
3156                                                 }
3157                                                 $this->mInterwiki = '';
3158                                                 $firstPass = false;
3159                                                 # Do another namespace split...
3160                                                 continue;
3161                                         }
3162
3163                                         # If there's an initial colon after the interwiki, that also
3164                                         # resets the default namespace
3165                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
3166                                                 $this->mNamespace = NS_MAIN;
3167                                                 $dbkey = substr( $dbkey, 1 );
3168                                         }
3169                                 }
3170                                 # If there's no recognized interwiki or namespace,
3171                                 # then let the colon expression be part of the title.
3172                         }
3173                         break;
3174                 } while ( true );
3175
3176                 # We already know that some pages won't be in the database!
3177                 if ( $this->mInterwiki != '' || NS_SPECIAL == $this->mNamespace ) {
3178                         $this->mArticleID = 0;
3179                 }
3180                 $fragment = strstr( $dbkey, '#' );
3181                 if ( false !== $fragment ) {
3182                         $this->setFragment( $fragment );
3183                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
3184                         # remove whitespace again: prevents "Foo_bar_#"
3185                         # becoming "Foo_bar_"
3186                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
3187                 }
3188
3189                 # Reject illegal characters.
3190                 $rxTc = self::getTitleInvalidRegex();
3191                 if ( preg_match( $rxTc, $dbkey ) ) {
3192                         return false;
3193                 }
3194
3195                 # Pages with "/./" or "/../" appearing in the URLs will often be un-
3196                 # reachable due to the way web browsers deal with 'relative' URLs.
3197                 # Also, they conflict with subpage syntax.  Forbid them explicitly.
3198                 if ( strpos( $dbkey, '.' ) !== false &&
3199                          ( $dbkey === '.' || $dbkey === '..' ||
3200                            strpos( $dbkey, './' ) === 0  ||
3201                            strpos( $dbkey, '../' ) === 0 ||
3202                            strpos( $dbkey, '/./' ) !== false ||
3203                            strpos( $dbkey, '/../' ) !== false  ||
3204                            substr( $dbkey, -2 ) == '/.' ||
3205                            substr( $dbkey, -3 ) == '/..' ) )
3206                 {
3207                         return false;
3208                 }
3209
3210                 # Magic tilde sequences? Nu-uh!
3211                 if ( strpos( $dbkey, '~~~' ) !== false ) {
3212                         return false;
3213                 }
3214
3215                 # Limit the size of titles to 255 bytes. This is typically the size of the
3216                 # underlying database field. We make an exception for special pages, which
3217                 # don't need to be stored in the database, and may edge over 255 bytes due
3218                 # to subpage syntax for long titles, e.g. [[Special:Block/Long name]]
3219                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
3220                   strlen( $dbkey ) > 512 )
3221                 {
3222                         return false;
3223                 }
3224
3225                 # Normally, all wiki links are forced to have an initial capital letter so [[foo]]
3226                 # and [[Foo]] point to the same place.  Don't force it for interwikis, since the
3227                 # other site might be case-sensitive.
3228                 $this->mUserCaseDBKey = $dbkey;
3229                 if ( $this->mInterwiki == '' ) {
3230                         $dbkey = self::capitalize( $dbkey, $this->mNamespace );
3231                 }
3232
3233                 # Can't make a link to a namespace alone... "empty" local links can only be
3234                 # self-links with a fragment identifier.
3235                 if ( $dbkey == '' && $this->mInterwiki == '' && $this->mNamespace != NS_MAIN ) {
3236                         return false;
3237                 }
3238
3239                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
3240                 // IP names are not allowed for accounts, and can only be referring to
3241                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
3242                 // there are numerous ways to present the same IP. Having sp:contribs scan
3243                 // them all is silly and having some show the edits and others not is
3244                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
3245                 $dbkey = ( $this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK )
3246                         ? IP::sanitizeIP( $dbkey )
3247                         : $dbkey;
3248
3249                 // Any remaining initial :s are illegal.
3250                 if ( $dbkey !== '' && ':' == $dbkey[0] ) {
3251                         return false;
3252                 }
3253
3254                 # Fill fields
3255                 $this->mDbkeyform = $dbkey;
3256                 $this->mUrlform = wfUrlencode( $dbkey );
3257
3258                 $this->mTextform = str_replace( '_', ' ', $dbkey );
3259
3260                 return true;
3261         }
3262
3263         /**
3264          * Get an array of Title objects linking to this Title
3265          * Also stores the IDs in the link cache.
3266          *
3267          * WARNING: do not use this function on arbitrary user-supplied titles!
3268          * On heavily-used templates it will max out the memory.
3269          *
3270          * @param $options Array: may be FOR UPDATE
3271          * @param $table String: table name
3272          * @param $prefix String: fields prefix
3273          * @return Array of Title objects linking here
3274          */
3275         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3276                 if ( count( $options ) > 0 ) {
3277                         $db = wfGetDB( DB_MASTER );
3278                 } else {
3279                         $db = wfGetDB( DB_SLAVE );
3280                 }
3281
3282                 $res = $db->select(
3283                         array( 'page', $table ),
3284                         self::getSelectFields(),
3285                         array(
3286                                 "{$prefix}_from=page_id",
3287                                 "{$prefix}_namespace" => $this->getNamespace(),
3288                                 "{$prefix}_title"     => $this->getDBkey() ),
3289                         __METHOD__,
3290                         $options
3291                 );
3292
3293                 $retVal = array();
3294                 if ( $res->numRows() ) {
3295                         $linkCache = LinkCache::singleton();
3296                         foreach ( $res as $row ) {
3297                                 $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title );
3298                                 if ( $titleObj ) {
3299                                         $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3300                                         $retVal[] = $titleObj;
3301                                 }
3302                         }
3303                 }
3304                 return $retVal;
3305         }
3306
3307         /**
3308          * Get an array of Title objects using this Title as a template
3309          * Also stores the IDs in the link cache.
3310          *
3311          * WARNING: do not use this function on arbitrary user-supplied titles!
3312          * On heavily-used templates it will max out the memory.
3313          *
3314          * @param $options Array: may be FOR UPDATE
3315          * @return Array of Title the Title objects linking here
3316          */
3317         public function getTemplateLinksTo( $options = array() ) {
3318                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
3319         }
3320
3321         /**
3322          * Get an array of Title objects linked from this Title
3323          * Also stores the IDs in the link cache.
3324          *
3325          * WARNING: do not use this function on arbitrary user-supplied titles!
3326          * On heavily-used templates it will max out the memory.
3327          *
3328          * @param $options Array: may be FOR UPDATE
3329          * @param $table String: table name
3330          * @param $prefix String: fields prefix
3331          * @return Array of Title objects linking here
3332          */
3333         public function getLinksFrom( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
3334                 global $wgContentHandlerUseDB;
3335
3336                 $id = $this->getArticleID();
3337
3338                 # If the page doesn't exist; there can't be any link from this page
3339                 if ( !$id ) {
3340                         return array();
3341                 }
3342
3343                 if ( count( $options ) > 0 ) {
3344                         $db = wfGetDB( DB_MASTER );
3345                 } else {
3346                         $db = wfGetDB( DB_SLAVE );
3347                 }
3348
3349                 $namespaceFiled = "{$prefix}_namespace";
3350                 $titleField = "{$prefix}_title";
3351
3352                 $fields = array( $namespaceFiled, $titleField, 'page_id', 'page_len', 'page_is_redirect', 'page_latest' );
3353                 if ( $wgContentHandlerUseDB ) $fields[] = 'page_content_model';
3354
3355                 $res = $db->select(
3356                         array( $table, 'page' ),
3357                         $fields,
3358                         array( "{$prefix}_from" => $id ),
3359                         __METHOD__,
3360                         $options,
3361                         array( 'page' => array( 'LEFT JOIN', array( "page_namespace=$namespaceFiled", "page_title=$titleField" ) ) )
3362                 );
3363
3364                 $retVal = array();
3365                 if ( $res->numRows() ) {
3366                         $linkCache = LinkCache::singleton();
3367                         foreach ( $res as $row ) {
3368                                 $titleObj = Title::makeTitle( $row->$namespaceFiled, $row->$titleField );
3369                                 if ( $titleObj ) {
3370                                         if ( $row->page_id ) {
3371                                                 $linkCache->addGoodLinkObjFromRow( $titleObj, $row );
3372                                         } else {
3373                                                 $linkCache->addBadLinkObj( $titleObj );
3374                                         }
3375                                         $retVal[] = $titleObj;
3376                                 }
3377                         }
3378                 }
3379                 return $retVal;
3380         }
3381
3382         /**
3383          * Get an array of Title objects used on this Title as a template
3384          * Also stores the IDs in the link cache.
3385          *
3386          * WARNING: do not use this function on arbitrary user-supplied titles!
3387          * On heavily-used templates it will max out the memory.
3388          *
3389          * @param $options Array: may be FOR UPDATE
3390          * @return Array of Title the Title objects used here
3391          */
3392         public function getTemplateLinksFrom( $options = array() ) {
3393                 return $this->getLinksFrom( $options, 'templatelinks', 'tl' );
3394         }
3395
3396         /**
3397          * Get an array of Title objects referring to non-existent articles linked from this page
3398          *
3399          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
3400          * @return Array of Title the Title objects
3401          */
3402         public function getBrokenLinksFrom() {
3403                 if ( $this->getArticleID() == 0 ) {
3404                         # All links from article ID 0 are false positives
3405                         return array();
3406                 }
3407
3408                 $dbr = wfGetDB( DB_SLAVE );
3409                 $res = $dbr->select(
3410                         array( 'page', 'pagelinks' ),
3411                         array( 'pl_namespace', 'pl_title' ),
3412                         array(
3413                                 'pl_from' => $this->getArticleID(),
3414                                 'page_namespace IS NULL'
3415                         ),
3416                         __METHOD__, array(),
3417                         array(
3418                                 'page' => array(
3419                                         'LEFT JOIN',
3420                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
3421                                 )
3422                         )
3423                 );
3424
3425                 $retVal = array();
3426                 foreach ( $res as $row ) {
3427                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
3428                 }
3429                 return $retVal;
3430         }
3431
3432
3433         /**
3434          * Get a list of URLs to purge from the Squid cache when this
3435          * page changes
3436          *
3437          * @return Array of String the URLs
3438          */
3439         public function getSquidURLs() {
3440                 $urls = array(
3441                         $this->getInternalURL(),
3442                         $this->getInternalURL( 'action=history' )
3443                 );
3444
3445                 $pageLang = $this->getPageLanguage();
3446                 if ( $pageLang->hasVariants() ) {
3447                         $variants = $pageLang->getVariants();
3448                         foreach ( $variants as $vCode ) {
3449                                 $urls[] = $this->getInternalURL( '', $vCode );
3450                         }
3451                 }
3452
3453                 return $urls;
3454         }
3455
3456         /**
3457          * Purge all applicable Squid URLs
3458          */
3459         public function purgeSquid() {
3460                 global $wgUseSquid;
3461                 if ( $wgUseSquid ) {
3462                         $urls = $this->getSquidURLs();
3463                         $u = new SquidUpdate( $urls );
3464                         $u->doUpdate();
3465                 }
3466         }
3467
3468         /**
3469          * Move this page without authentication
3470          *
3471          * @param $nt Title the new page Title
3472          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3473          */
3474         public function moveNoAuth( &$nt ) {
3475                 return $this->moveTo( $nt, false );
3476         }
3477
3478         /**
3479          * Check whether a given move operation would be valid.
3480          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
3481          *
3482          * @param $nt Title the new title
3483          * @param $auth Bool indicates whether $wgUser's permissions
3484          *  should be checked
3485          * @param $reason String is the log summary of the move, used for spam checking
3486          * @return Mixed True on success, getUserPermissionsErrors()-like array on failure
3487          */
3488         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
3489                 global $wgUser, $wgContentHandlerUseDB;
3490
3491                 $errors = array();
3492                 if ( !$nt ) {
3493                         // Normally we'd add this to $errors, but we'll get
3494                         // lots of syntax errors if $nt is not an object
3495                         return array( array( 'badtitletext' ) );
3496                 }
3497                 if ( $this->equals( $nt ) ) {
3498                         $errors[] = array( 'selfmove' );
3499                 }
3500                 if ( !$this->isMovable() ) {
3501                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
3502                 }
3503                 if ( $nt->getInterwiki() != '' ) {
3504                         $errors[] = array( 'immobile-target-namespace-iw' );
3505                 }
3506                 if ( !$nt->isMovable() ) {
3507                         $errors[] = array( 'immobile-target-namespace', $nt->getNsText() );
3508                 }
3509
3510                 $oldid = $this->getArticleID();
3511                 $newid = $nt->getArticleID();
3512
3513                 if ( strlen( $nt->getDBkey() ) < 1 ) {
3514                         $errors[] = array( 'articleexists' );
3515                 }
3516                 if ( ( $this->getDBkey() == '' ) ||
3517                          ( !$oldid ) ||
3518                          ( $nt->getDBkey() == '' ) ) {
3519                         $errors[] = array( 'badarticleerror' );
3520                 }
3521
3522                 // Content model checks
3523                 if ( !$wgContentHandlerUseDB &&
3524                                 $this->getContentModel() !== $nt->getContentModel() ) {
3525                         // can't move a page if that would change the page's content model
3526                         $errors[] = array(
3527                                 'bad-target-model',
3528                                 ContentHandler::getLocalizedName( $this->getContentModel() ),
3529                                 ContentHandler::getLocalizedName( $nt->getContentModel() )
3530                         );
3531                 }
3532
3533                 // Image-specific checks
3534                 if ( $this->getNamespace() == NS_FILE ) {
3535                         $errors = array_merge( $errors, $this->validateFileMoveOperation( $nt ) );
3536                 }
3537
3538                 if ( $nt->getNamespace() == NS_FILE && $this->getNamespace() != NS_FILE ) {
3539                         $errors[] = array( 'nonfile-cannot-move-to-file' );
3540                 }
3541
3542                 if ( $auth ) {
3543                         $errors = wfMergeErrorArrays( $errors,
3544                                 $this->getUserPermissionsErrors( 'move', $wgUser ),
3545                                 $this->getUserPermissionsErrors( 'edit', $wgUser ),
3546                                 $nt->getUserPermissionsErrors( 'move-target', $wgUser ),
3547                                 $nt->getUserPermissionsErrors( 'edit', $wgUser ) );
3548                 }
3549
3550                 $match = EditPage::matchSummarySpamRegex( $reason );
3551                 if ( $match !== false ) {
3552                         // This is kind of lame, won't display nice
3553                         $errors[] = array( 'spamprotectiontext' );
3554                 }
3555
3556                 $err = null;
3557                 if ( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
3558                         $errors[] = array( 'hookaborted', $err );
3559                 }
3560
3561                 # The move is allowed only if (1) the target doesn't exist, or
3562                 # (2) the target is a redirect to the source, and has no history
3563                 # (so we can undo bad moves right after they're done).
3564
3565                 if ( 0 != $newid ) { # Target exists; check for validity
3566                         if ( !$this->isValidMoveTarget( $nt ) ) {
3567                                 $errors[] = array( 'articleexists' );
3568                         }
3569                 } else {
3570                         $tp = $nt->getTitleProtection();
3571                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
3572                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
3573                                 $errors[] = array( 'cantmove-titleprotected' );
3574                         }
3575                 }
3576                 if ( empty( $errors ) ) {
3577                         return true;
3578                 }
3579                 return $errors;
3580         }
3581
3582         /**
3583          * Check if the requested move target is a valid file move target
3584          * @param Title $nt Target title
3585          * @return array List of errors
3586          */
3587         protected function validateFileMoveOperation( $nt ) {
3588                 global $wgUser;
3589
3590                 $errors = array();
3591
3592                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is not allowed until below
3593
3594                 $file = wfLocalFile( $this );
3595                 if ( $file->exists() ) {
3596                         if ( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
3597                                 $errors[] = array( 'imageinvalidfilename' );
3598                         }
3599                         if ( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
3600                                 $errors[] = array( 'imagetypemismatch' );
3601                         }
3602                 }
3603
3604                 if ( $nt->getNamespace() != NS_FILE ) {
3605                         $errors[] = array( 'imagenocrossnamespace' );
3606                         // From here we want to do checks on a file object, so if we can't
3607                         // create one, we must return.
3608                         return $errors;
3609                 }
3610
3611                 // wfFindFile( $nt ) / wfLocalFile( $nt ) is allowed below here
3612
3613                 $destFile = wfLocalFile( $nt );
3614                 if ( !$wgUser->isAllowed( 'reupload-shared' ) && !$destFile->exists() && wfFindFile( $nt ) ) {
3615                         $errors[] = array( 'file-exists-sharedrepo' );
3616                 }
3617
3618                 return $errors;
3619         }
3620
3621         /**
3622          * Move a title to a new location
3623          *
3624          * @param $nt Title the new title
3625          * @param $auth Bool indicates whether $wgUser's permissions
3626          *  should be checked
3627          * @param $reason String the reason for the move
3628          * @param $createRedirect Bool Whether to create a redirect from the old title to the new title.
3629          *  Ignored if the user doesn't have the suppressredirect right.
3630          * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
3631          */
3632         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
3633                 global $wgUser;
3634                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
3635                 if ( is_array( $err ) ) {
3636                         // Auto-block user's IP if the account was "hard" blocked
3637                         $wgUser->spreadAnyEditBlock();
3638                         return $err;
3639                 }
3640                 // Check suppressredirect permission
3641                 if ( $auth && !$wgUser->isAllowed( 'suppressredirect' ) ) {
3642                         $createRedirect = true;
3643                 }
3644
3645                 // If it is a file, move it first.
3646                 // It is done before all other moving stuff is done because it's hard to revert.
3647                 $dbw = wfGetDB( DB_MASTER );
3648                 if ( $this->getNamespace() == NS_FILE ) {
3649                         $file = wfLocalFile( $this );
3650                         if ( $file->exists() ) {
3651                                 $status = $file->move( $nt );
3652                                 if ( !$status->isOk() ) {
3653                                         return $status->getErrorsArray();
3654                                 }
3655                         }
3656                         // Clear RepoGroup process cache
3657                         RepoGroup::singleton()->clearCache( $this );
3658                         RepoGroup::singleton()->clearCache( $nt ); # clear false negative cache
3659                 }
3660
3661                 $dbw->begin( __METHOD__ ); # If $file was a LocalFile, its transaction would have closed our own.
3662                 $pageid = $this->getArticleID( self::GAID_FOR_UPDATE );
3663                 $protected = $this->isProtected();
3664
3665                 // Do the actual move
3666                 $this->moveToInternal( $nt, $reason, $createRedirect );
3667
3668                 // Refresh the sortkey for this row.  Be careful to avoid resetting
3669                 // cl_timestamp, which may disturb time-based lists on some sites.
3670                 $prefixes = $dbw->select(
3671                         'categorylinks',
3672                         array( 'cl_sortkey_prefix', 'cl_to' ),
3673                         array( 'cl_from' => $pageid ),
3674                         __METHOD__
3675                 );
3676                 foreach ( $prefixes as $prefixRow ) {
3677                         $prefix = $prefixRow->cl_sortkey_prefix;
3678                         $catTo = $prefixRow->cl_to;
3679                         $dbw->update( 'categorylinks',
3680                                 array(
3681                                         'cl_sortkey' => Collation::singleton()->getSortKey(
3682                                                 $nt->getCategorySortkey( $prefix ) ),
3683                                         'cl_timestamp=cl_timestamp' ),
3684                                 array(
3685                                         'cl_from' => $pageid,
3686                                         'cl_to' => $catTo ),
3687                                 __METHOD__
3688                         );
3689                 }
3690
3691                 $redirid = $this->getArticleID();
3692
3693                 if ( $protected ) {
3694                         # Protect the redirect title as the title used to be...
3695                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
3696                                 array(
3697                                         'pr_page'    => $redirid,
3698                                         'pr_type'    => 'pr_type',
3699                                         'pr_level'   => 'pr_level',
3700                                         'pr_cascade' => 'pr_cascade',
3701                                         'pr_user'    => 'pr_user',
3702                                         'pr_expiry'  => 'pr_expiry'
3703                                 ),
3704                                 array( 'pr_page' => $pageid ),
3705                                 __METHOD__,
3706                                 array( 'IGNORE' )
3707                         );
3708                         # Update the protection log
3709                         $log = new LogPage( 'protect' );
3710                         $comment = wfMessage(
3711                                 'prot_1movedto2',
3712                                 $this->getPrefixedText(),
3713                                 $nt->getPrefixedText()
3714                         )->inContentLanguage()->text();
3715                         if ( $reason ) {
3716                                 $comment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
3717                         }
3718                         // @todo FIXME: $params?
3719                         $log->addEntry( 'move_prot', $nt, $comment, array( $this->getPrefixedText() ) );
3720                 }
3721
3722                 # Update watchlists
3723                 $oldnamespace = MWNamespace::getSubject( $this->getNamespace() );
3724                 $newnamespace = MWNamespace::getSubject( $nt->getNamespace() );
3725                 $oldtitle = $this->getDBkey();
3726                 $newtitle = $nt->getDBkey();
3727
3728                 if ( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
3729                         WatchedItem::duplicateEntries( $this, $nt );
3730                 }
3731
3732                 $dbw->commit( __METHOD__ );
3733
3734                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
3735                 return true;
3736         }
3737
3738         /**
3739          * Move page to a title which is either a redirect to the
3740          * source page or nonexistent
3741          *
3742          * @param $nt Title the page to move to, which should be a redirect or nonexistent
3743          * @param $reason String The reason for the move
3744          * @param $createRedirect Bool Whether to leave a redirect at the old title. Does not check
3745          *   if the user has the suppressredirect right
3746          * @throws MWException
3747          */
3748         private function moveToInternal( &$nt, $reason = '', $createRedirect = true ) {
3749                 global $wgUser, $wgContLang;
3750
3751                 if ( $nt->exists() ) {
3752                         $moveOverRedirect = true;
3753                         $logType = 'move_redir';
3754                 } else {
3755                         $moveOverRedirect = false;
3756                         $logType = 'move';
3757                 }
3758
3759                 if ( $createRedirect ) {
3760                         $contentHandler = ContentHandler::getForTitle( $this );
3761                         $redirectContent = $contentHandler->makeRedirectContent( $nt );
3762
3763                         // NOTE: If this page's content model does not support redirects, $redirectContent will be null.
3764                 } else {
3765                         $redirectContent = null;
3766                 }
3767
3768                 $logEntry = new ManualLogEntry( 'move', $logType );
3769                 $logEntry->setPerformer( $wgUser );
3770                 $logEntry->setTarget( $this );
3771                 $logEntry->setComment( $reason );
3772                 $logEntry->setParameters( array(
3773                         '4::target' => $nt->getPrefixedText(),
3774                         '5::noredir' => $redirectContent ? '0': '1',
3775                 ) );
3776
3777                 $formatter = LogFormatter::newFromEntry( $logEntry );
3778                 $formatter->setContext( RequestContext::newExtraneousContext( $this ) );
3779                 $comment = $formatter->getPlainActionText();
3780                 if ( $reason ) {
3781                         $comment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
3782                 }
3783                 # Truncate for whole multibyte characters.
3784                 $comment = $wgContLang->truncate( $comment, 255 );
3785
3786                 $oldid = $this->getArticleID();
3787
3788                 $dbw = wfGetDB( DB_MASTER );
3789
3790                 $newpage = WikiPage::factory( $nt );
3791
3792                 if ( $moveOverRedirect ) {
3793                         $newid = $nt->getArticleID();
3794
3795                         # Delete the old redirect. We don't save it to history since
3796                         # by definition if we've got here it's rather uninteresting.
3797                         # We have to remove it so that the next step doesn't trigger
3798                         # a conflict on the unique namespace+title index...
3799                         $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
3800
3801                         $newpage->doDeleteUpdates( $newid );
3802                 }
3803
3804                 # Save a null revision in the page's history notifying of the move
3805                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
3806                 if ( !is_object( $nullRevision ) ) {
3807                         throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
3808                 }
3809
3810                 $nullRevision->insertOn( $dbw );
3811
3812                 # Change the name of the target page:
3813                 $dbw->update( 'page',
3814                         /* SET */ array(
3815                                 'page_namespace' => $nt->getNamespace(),
3816                                 'page_title'     => $nt->getDBkey(),
3817                         ),
3818                         /* WHERE */ array( 'page_id' => $oldid ),
3819                         __METHOD__
3820                 );
3821
3822                 $this->resetArticleID( 0 );
3823                 $nt->resetArticleID( $oldid );
3824
3825                 $newpage->updateRevisionOn( $dbw, $nullRevision );
3826
3827                 wfRunHooks( 'NewRevisionFromEditComplete',
3828                         array( $newpage, $nullRevision, $nullRevision->getParentId(), $wgUser ) );
3829
3830                 $newpage->doEditUpdates( $nullRevision, $wgUser, array( 'changed' => false ) );
3831
3832                 if ( !$moveOverRedirect ) {
3833                         WikiPage::onArticleCreate( $nt );
3834                 }
3835
3836                 # Recreate the redirect, this time in the other direction.
3837                 if ( !$redirectContent ) {
3838                         WikiPage::onArticleDelete( $this );
3839                 } else {
3840                         $redirectArticle = WikiPage::factory( $this );
3841                         $newid = $redirectArticle->insertOn( $dbw );
3842                         if ( $newid ) { // sanity
3843                                 $redirectRevision = new Revision( array(
3844                                         'title'   => $this, // for determining the default content model
3845                                         'page'    => $newid,
3846                                         'comment' => $comment,
3847                                         'content'    => $redirectContent ) );
3848                                 $redirectRevision->insertOn( $dbw );
3849                                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
3850
3851                                 wfRunHooks( 'NewRevisionFromEditComplete',
3852                                         array( $redirectArticle, $redirectRevision, false, $wgUser ) );
3853
3854                                 $redirectArticle->doEditUpdates( $redirectRevision, $wgUser, array( 'created' => true ) );
3855                         }
3856                 }
3857
3858                 # Log the move
3859                 $logid = $logEntry->insert();
3860                 $logEntry->publish( $logid );
3861         }
3862
3863         /**
3864          * Move this page's subpages to be subpages of $nt
3865          *
3866          * @param $nt Title Move target
3867          * @param $auth bool Whether $wgUser's permissions should be checked
3868          * @param $reason string The reason for the move
3869          * @param $createRedirect bool Whether to create redirects from the old subpages to
3870          *     the new ones Ignored if the user doesn't have the 'suppressredirect' right
3871          * @return mixed array with old page titles as keys, and strings (new page titles) or
3872          *     arrays (errors) as values, or an error array with numeric indices if no pages
3873          *     were moved
3874          */
3875         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
3876                 global $wgMaximumMovedPages;
3877                 // Check permissions
3878                 if ( !$this->userCan( 'move-subpages' ) ) {
3879                         return array( 'cant-move-subpages' );
3880                 }
3881                 // Do the source and target namespaces support subpages?
3882                 if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
3883                         return array( 'namespace-nosubpages',
3884                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
3885                 }
3886                 if ( !MWNamespace::hasSubpages( $nt->getNamespace() ) ) {
3887                         return array( 'namespace-nosubpages',
3888                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
3889                 }
3890
3891                 $subpages = $this->getSubpages( $wgMaximumMovedPages + 1 );
3892                 $retval = array();
3893                 $count = 0;
3894                 foreach ( $subpages as $oldSubpage ) {
3895                         $count++;
3896                         if ( $count > $wgMaximumMovedPages ) {
3897                                 $retval[$oldSubpage->getPrefixedTitle()] =
3898                                                 array( 'movepage-max-pages',
3899                                                         $wgMaximumMovedPages );
3900                                 break;
3901                         }
3902
3903                         // We don't know whether this function was called before
3904                         // or after moving the root page, so check both
3905                         // $this and $nt
3906                         if ( $oldSubpage->getArticleID() == $this->getArticleID() ||
3907                                         $oldSubpage->getArticleID() == $nt->getArticleID() )
3908                         {
3909                                 // When moving a page to a subpage of itself,
3910                                 // don't move it twice
3911                                 continue;
3912                         }
3913                         $newPageName = preg_replace(
3914                                         '#^' . preg_quote( $this->getDBkey(), '#' ) . '#',
3915                                         StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
3916                                         $oldSubpage->getDBkey() );
3917                         if ( $oldSubpage->isTalkPage() ) {
3918                                 $newNs = $nt->getTalkPage()->getNamespace();
3919                         } else {
3920                                 $newNs = $nt->getSubjectPage()->getNamespace();
3921                         }
3922                         # Bug 14385: we need makeTitleSafe because the new page names may
3923                         # be longer than 255 characters.
3924                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3925
3926                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3927                         if ( $success === true ) {
3928                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3929                         } else {
3930                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3931                         }
3932                 }
3933                 return $retval;
3934         }
3935
3936         /**
3937          * Checks if this page is just a one-rev redirect.
3938          * Adds lock, so don't use just for light purposes.
3939          *
3940          * @return Bool
3941          */
3942         public function isSingleRevRedirect() {
3943                 global $wgContentHandlerUseDB;
3944
3945                 $dbw = wfGetDB( DB_MASTER );
3946
3947                 # Is it a redirect?
3948                 $fields = array( 'page_is_redirect', 'page_latest', 'page_id' );
3949                 if ( $wgContentHandlerUseDB ) $fields[] = 'page_content_model';
3950
3951                 $row = $dbw->selectRow( 'page',
3952                         $fields,
3953                         $this->pageCond(),
3954                         __METHOD__,
3955                         array( 'FOR UPDATE' )
3956                 );
3957                 # Cache some fields we may want
3958                 $this->mArticleID = $row ? intval( $row->page_id ) : 0;
3959                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3960                 $this->mLatestID = $row ? intval( $row->page_latest ) : false;
3961                 $this->mContentModel = $row && isset( $row->page_content_model ) ? strval( $row->page_content_model ) : false;
3962                 if ( !$this->mRedirect ) {
3963                         return false;
3964                 }
3965                 # Does the article have a history?
3966                 $row = $dbw->selectField( array( 'page', 'revision' ),
3967                         'rev_id',
3968                         array( 'page_namespace' => $this->getNamespace(),
3969                                 'page_title' => $this->getDBkey(),
3970                                 'page_id=rev_page',
3971                                 'page_latest != rev_id'
3972                         ),
3973                         __METHOD__,
3974                         array( 'FOR UPDATE' )
3975                 );
3976                 # Return true if there was no history
3977                 return ( $row === false );
3978         }
3979
3980         /**
3981          * Checks if $this can be moved to a given Title
3982          * - Selects for update, so don't call it unless you mean business
3983          *
3984          * @param $nt Title the new title to check
3985          * @return Bool
3986          */
3987         public function isValidMoveTarget( $nt ) {
3988                 # Is it an existing file?
3989                 if ( $nt->getNamespace() == NS_FILE ) {
3990                         $file = wfLocalFile( $nt );
3991                         if ( $file->exists() ) {
3992                                 wfDebug( __METHOD__ . ": file exists\n" );
3993                                 return false;
3994                         }
3995                 }
3996                 # Is it a redirect with no history?
3997                 if ( !$nt->isSingleRevRedirect() ) {
3998                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3999                         return false;
4000                 }
4001                 # Get the article text
4002                 $rev = Revision::newFromTitle( $nt, false, Revision::READ_LATEST );
4003                 if( !is_object( $rev ) ) {
4004                         return false;
4005                 }
4006                 $content = $rev->getContent();
4007                 # Does the redirect point to the source?
4008                 # Or is it a broken self-redirect, usually caused by namespace collisions?
4009                 $redirTitle = $content ? $content->getRedirectTarget() : null;
4010
4011                 if ( $redirTitle ) {
4012                         if ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
4013                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) {
4014                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
4015                                 return false;
4016                         } else {
4017                                 return true;
4018                         }
4019                 } else {
4020                         # Fail safe (not a redirect after all. strange.)
4021                         wfDebug( __METHOD__ . ": failsafe: database sais " . $nt->getPrefixedDBkey() .
4022                                                 " is a redirect, but it doesn't contain a valid redirect.\n" );
4023                         return false;
4024                 }
4025         }
4026
4027         /**
4028          * Get categories to which this Title belongs and return an array of
4029          * categories' names.
4030          *
4031          * @return Array of parents in the form:
4032          *        $parent => $currentarticle
4033          */
4034         public function getParentCategories() {
4035                 global $wgContLang;
4036
4037                 $data = array();
4038
4039                 $titleKey = $this->getArticleID();
4040
4041                 if ( $titleKey === 0 ) {
4042                         return $data;
4043                 }
4044
4045                 $dbr = wfGetDB( DB_SLAVE );
4046
4047                 $res = $dbr->select(
4048                         'categorylinks',
4049                         'cl_to',
4050                         array( 'cl_from' => $titleKey ),
4051                         __METHOD__
4052                 );
4053
4054                 if ( $res->numRows() > 0 ) {
4055                         foreach ( $res as $row ) {
4056                                 // $data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
4057                                 $data[$wgContLang->getNSText( NS_CATEGORY ) . ':' . $row->cl_to] = $this->getFullText();
4058                         }
4059                 }
4060                 return $data;
4061         }
4062
4063         /**
4064          * Get a tree of parent categories
4065          *
4066          * @param $children Array with the children in the keys, to check for circular refs
4067          * @return Array Tree of parent categories
4068          */
4069         public function getParentCategoryTree( $children = array() ) {
4070                 $stack = array();
4071                 $parents = $this->getParentCategories();
4072
4073                 if ( $parents ) {
4074                         foreach ( $parents as $parent => $current ) {
4075                                 if ( array_key_exists( $parent, $children ) ) {
4076                                         # Circular reference
4077                                         $stack[$parent] = array();
4078                                 } else {
4079                                         $nt = Title::newFromText( $parent );
4080                                         if ( $nt ) {
4081                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array( $parent => 1 ) );
4082                                         }
4083                                 }
4084                         }
4085                 }
4086
4087                 return $stack;
4088         }
4089
4090         /**
4091          * Get an associative array for selecting this title from
4092          * the "page" table
4093          *
4094          * @return Array suitable for the $where parameter of DB::select()
4095          */
4096         public function pageCond() {
4097                 if ( $this->mArticleID > 0 ) {
4098                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
4099                         return array( 'page_id' => $this->mArticleID );
4100                 } else {
4101                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
4102                 }
4103         }
4104
4105         /**
4106          * Get the revision ID of the previous revision
4107          *
4108          * @param $revId Int Revision ID. Get the revision that was before this one.
4109          * @param $flags Int Title::GAID_FOR_UPDATE
4110          * @return Int|Bool Old revision ID, or FALSE if none exists
4111          */
4112         public function getPreviousRevisionID( $revId, $flags = 0 ) {
4113                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4114                 $revId = $db->selectField( 'revision', 'rev_id',
4115                         array(
4116                                 'rev_page' => $this->getArticleID( $flags ),
4117                                 'rev_id < ' . intval( $revId )
4118                         ),
4119                         __METHOD__,
4120                         array( 'ORDER BY' => 'rev_id DESC' )
4121                 );
4122
4123                 if ( $revId === false ) {
4124                         return false;
4125                 } else {
4126                         return intval( $revId );
4127                 }
4128         }
4129
4130         /**
4131          * Get the revision ID of the next revision
4132          *
4133          * @param $revId Int Revision ID. Get the revision that was after this one.
4134          * @param $flags Int Title::GAID_FOR_UPDATE
4135          * @return Int|Bool Next revision ID, or FALSE if none exists
4136          */
4137         public function getNextRevisionID( $revId, $flags = 0 ) {
4138                 $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4139                 $revId = $db->selectField( 'revision', 'rev_id',
4140                         array(
4141                                 'rev_page' => $this->getArticleID( $flags ),
4142                                 'rev_id > ' . intval( $revId )
4143                         ),
4144                         __METHOD__,
4145                         array( 'ORDER BY' => 'rev_id' )
4146                 );
4147
4148                 if ( $revId === false ) {
4149                         return false;
4150                 } else {
4151                         return intval( $revId );
4152                 }
4153         }
4154
4155         /**
4156          * Get the first revision of the page
4157          *
4158          * @param $flags Int Title::GAID_FOR_UPDATE
4159          * @return Revision|Null if page doesn't exist
4160          */
4161         public function getFirstRevision( $flags = 0 ) {
4162                 $pageId = $this->getArticleID( $flags );
4163                 if ( $pageId ) {
4164                         $db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
4165                         $row = $db->selectRow( 'revision', Revision::selectFields(),
4166                                 array( 'rev_page' => $pageId ),
4167                                 __METHOD__,
4168                                 array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
4169                         );
4170                         if ( $row ) {
4171                                 return new Revision( $row );
4172                         }
4173                 }
4174                 return null;
4175         }
4176
4177         /**
4178          * Get the oldest revision timestamp of this page
4179          *
4180          * @param $flags Int Title::GAID_FOR_UPDATE
4181          * @return String: MW timestamp
4182          */
4183         public function getEarliestRevTime( $flags = 0 ) {
4184                 $rev = $this->getFirstRevision( $flags );
4185                 return $rev ? $rev->getTimestamp() : null;
4186         }
4187
4188         /**
4189          * Check if this is a new page
4190          *
4191          * @return bool
4192          */
4193         public function isNewPage() {
4194                 $dbr = wfGetDB( DB_SLAVE );
4195                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
4196         }
4197
4198         /**
4199          * Check whether the number of revisions of this page surpasses $wgDeleteRevisionsLimit
4200          *
4201          * @return bool
4202          */
4203         public function isBigDeletion() {
4204                 global $wgDeleteRevisionsLimit;
4205
4206                 if ( !$wgDeleteRevisionsLimit ) {
4207                         return false;
4208                 }
4209
4210                 $revCount = $this->estimateRevisionCount();
4211                 return $revCount > $wgDeleteRevisionsLimit;
4212         }
4213
4214         /**
4215          * Get the  approximate revision count of this page.
4216          *
4217          * @return int
4218          */
4219         public function estimateRevisionCount() {
4220                 if ( !$this->exists() ) {
4221                         return 0;
4222                 }
4223
4224                 if ( $this->mEstimateRevisions === null ) {
4225                         $dbr = wfGetDB( DB_SLAVE );
4226                         $this->mEstimateRevisions = $dbr->estimateRowCount( 'revision', '*',
4227                                 array( 'rev_page' => $this->getArticleID() ), __METHOD__ );
4228                 }
4229
4230                 return $this->mEstimateRevisions;
4231         }
4232
4233         /**
4234          * Get the number of revisions between the given revision.
4235          * Used for diffs and other things that really need it.
4236          *
4237          * @param $old int|Revision Old revision or rev ID (first before range)
4238          * @param $new int|Revision New revision or rev ID (first after range)
4239          * @return Int Number of revisions between these revisions.
4240          */
4241         public function countRevisionsBetween( $old, $new ) {
4242                 if ( !( $old instanceof Revision ) ) {
4243                         $old = Revision::newFromTitle( $this, (int)$old );
4244                 }
4245                 if ( !( $new instanceof Revision ) ) {
4246                         $new = Revision::newFromTitle( $this, (int)$new );
4247                 }
4248                 if ( !$old || !$new ) {
4249                         return 0; // nothing to compare
4250                 }
4251                 $dbr = wfGetDB( DB_SLAVE );
4252                 return (int)$dbr->selectField( 'revision', 'count(*)',
4253                         array(
4254                                 'rev_page' => $this->getArticleID(),
4255                                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4256                                 'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4257                         ),
4258                         __METHOD__
4259                 );
4260         }
4261
4262         /**
4263          * Get the number of authors between the given revisions or revision IDs.
4264          * Used for diffs and other things that really need it.
4265          *
4266          * @param $old int|Revision Old revision or rev ID (first before range by default)
4267          * @param $new int|Revision New revision or rev ID (first after range by default)
4268          * @param $limit int Maximum number of authors
4269          * @param $options string|array (Optional): Single option, or an array of options:
4270          *     'include_old' Include $old in the range; $new is excluded.
4271          *     'include_new' Include $new in the range; $old is excluded.
4272          *     'include_both' Include both $old and $new in the range.
4273          *     Unknown option values are ignored.
4274          * @return int Number of revision authors in the range; zero if not both revisions exist
4275          */
4276         public function countAuthorsBetween( $old, $new, $limit, $options = array() ) {
4277                 if ( !( $old instanceof Revision ) ) {
4278                         $old = Revision::newFromTitle( $this, (int)$old );
4279                 }
4280                 if ( !( $new instanceof Revision ) ) {
4281                         $new = Revision::newFromTitle( $this, (int)$new );
4282                 }
4283                 // XXX: what if Revision objects are passed in, but they don't refer to this title?
4284                 // Add $old->getPage() != $new->getPage() || $old->getPage() != $this->getArticleID()
4285                 // in the sanity check below?
4286                 if ( !$old || !$new ) {
4287                         return 0; // nothing to compare
4288                 }
4289                 $old_cmp = '>';
4290                 $new_cmp = '<';
4291                 $options = (array) $options;
4292                 if ( in_array( 'include_old', $options ) ) {
4293                         $old_cmp = '>=';
4294                 }
4295                 if ( in_array( 'include_new', $options ) ) {
4296                         $new_cmp = '<=';
4297                 }
4298                 if ( in_array( 'include_both', $options ) ) {
4299                         $old_cmp = '>=';
4300                         $new_cmp = '<=';
4301                 }
4302                 // No DB query needed if $old and $new are the same or successive revisions:
4303                 if ( $old->getId() === $new->getId() ) {
4304                         return ( $old_cmp === '>' && $new_cmp === '<' ) ? 0 : 1;
4305                 } else if ( $old->getId() === $new->getParentId() ) {
4306                         if ( $old_cmp === '>' || $new_cmp === '<' ) {
4307                                 return ( $old_cmp === '>' && $new_cmp === '<' ) ? 0 : 1;
4308                         }
4309                         return ( $old->getRawUserText() === $new->getRawUserText() ) ? 1 : 2;
4310                 }
4311                 $dbr = wfGetDB( DB_SLAVE );
4312                 $res = $dbr->select( 'revision', 'DISTINCT rev_user_text',
4313                         array(
4314                                 'rev_page' => $this->getArticleID(),
4315                                 "rev_timestamp $old_cmp " . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
4316                                 "rev_timestamp $new_cmp " . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
4317                         ), __METHOD__,
4318                         array( 'LIMIT' => $limit + 1 ) // add one so caller knows it was truncated
4319                 );
4320                 return (int)$dbr->numRows( $res );
4321         }
4322
4323         /**
4324          * Compare with another title.
4325          *
4326          * @param $title Title
4327          * @return Bool
4328          */
4329         public function equals( Title $title ) {
4330                 // Note: === is necessary for proper matching of number-like titles.
4331                 return $this->getInterwiki() === $title->getInterwiki()
4332                         && $this->getNamespace() == $title->getNamespace()
4333                         && $this->getDBkey() === $title->getDBkey();
4334         }
4335
4336         /**
4337          * Check if this title is a subpage of another title
4338          *
4339          * @param $title Title
4340          * @return Bool
4341          */
4342         public function isSubpageOf( Title $title ) {
4343                 return $this->getInterwiki() === $title->getInterwiki()
4344                         && $this->getNamespace() == $title->getNamespace()
4345                         && strpos( $this->getDBkey(), $title->getDBkey() . '/' ) === 0;
4346         }
4347
4348         /**
4349          * Check if page exists.  For historical reasons, this function simply
4350          * checks for the existence of the title in the page table, and will
4351          * thus return false for interwiki links, special pages and the like.
4352          * If you want to know if a title can be meaningfully viewed, you should
4353          * probably call the isKnown() method instead.
4354          *
4355          * @return Bool
4356          */
4357         public function exists() {
4358                 return $this->getArticleID() != 0;
4359         }
4360
4361         /**
4362          * Should links to this title be shown as potentially viewable (i.e. as
4363          * "bluelinks"), even if there's no record by this title in the page
4364          * table?
4365          *
4366          * This function is semi-deprecated for public use, as well as somewhat
4367          * misleadingly named.  You probably just want to call isKnown(), which
4368          * calls this function internally.
4369          *
4370          * (ISSUE: Most of these checks are cheap, but the file existence check
4371          * can potentially be quite expensive.  Including it here fixes a lot of
4372          * existing code, but we might want to add an optional parameter to skip
4373          * it and any other expensive checks.)
4374          *
4375          * @return Bool
4376          */
4377         public function isAlwaysKnown() {
4378                 $isKnown = null;
4379
4380                 /**
4381                  * Allows overriding default behaviour for determining if a page exists.
4382                  * If $isKnown is kept as null, regular checks happen. If it's
4383                  * a boolean, this value is returned by the isKnown method.
4384                  *
4385                  * @since 1.20
4386                  *
4387                  * @param Title $title
4388                  * @param boolean|null $isKnown
4389                  */
4390                 wfRunHooks( 'TitleIsAlwaysKnown', array( $this, &$isKnown ) );
4391
4392                 if ( !is_null( $isKnown ) ) {
4393                         return $isKnown;
4394                 }
4395
4396                 if ( $this->mInterwiki != '' ) {
4397                         return true;  // any interwiki link might be viewable, for all we know
4398                 }
4399
4400                 switch( $this->mNamespace ) {
4401                         case NS_MEDIA:
4402                         case NS_FILE:
4403                                 // file exists, possibly in a foreign repo
4404                                 return (bool)wfFindFile( $this );
4405                         case NS_SPECIAL:
4406                                 // valid special page
4407                                 return SpecialPageFactory::exists( $this->getDBkey() );
4408                         case NS_MAIN:
4409                                 // selflink, possibly with fragment
4410                                 return $this->mDbkeyform == '';
4411                         case NS_MEDIAWIKI:
4412                                 // known system message
4413                                 return $this->hasSourceText() !== false;
4414                         default:
4415                                 return false;
4416                 }
4417         }
4418
4419         /**
4420          * Does this title refer to a page that can (or might) be meaningfully
4421          * viewed?  In particular, this function may be used to determine if
4422          * links to the title should be rendered as "bluelinks" (as opposed to
4423          * "redlinks" to non-existent pages).
4424          * Adding something else to this function will cause inconsistency
4425          * since LinkHolderArray calls isAlwaysKnown() and does its own
4426          * page existence check.
4427          *
4428          * @return Bool
4429          */
4430         public function isKnown() {
4431                 return $this->isAlwaysKnown() || $this->exists();
4432         }
4433
4434         /**
4435          * Does this page have source text?
4436          *
4437          * @return Boolean
4438          */
4439         public function hasSourceText() {
4440                 if ( $this->exists() ) {
4441                         return true;
4442                 }
4443
4444                 if ( $this->mNamespace == NS_MEDIAWIKI ) {
4445                         // If the page doesn't exist but is a known system message, default
4446                         // message content will be displayed, same for language subpages-
4447                         // Use always content language to avoid loading hundreds of languages
4448                         // to get the link color.
4449                         global $wgContLang;
4450                         list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4451                         $message = wfMessage( $name )->inLanguage( $wgContLang )->useDatabase( false );
4452                         return $message->exists();
4453                 }
4454
4455                 return false;
4456         }
4457
4458         /**
4459          * Get the default message text or false if the message doesn't exist
4460          *
4461          * @return String or false
4462          */
4463         public function getDefaultMessageText() {
4464                 global $wgContLang;
4465
4466                 if ( $this->getNamespace() != NS_MEDIAWIKI ) { // Just in case
4467                         return false;
4468                 }
4469
4470                 list( $name, $lang ) = MessageCache::singleton()->figureMessage( $wgContLang->lcfirst( $this->getText() ) );
4471                 $message = wfMessage( $name )->inLanguage( $lang )->useDatabase( false );
4472
4473                 if ( $message->exists() ) {
4474                         return $message->plain();
4475                 } else {
4476                         return false;
4477                 }
4478         }
4479
4480         /**
4481          * Updates page_touched for this page; called from LinksUpdate.php
4482          *
4483          * @return Bool true if the update succeded
4484          */
4485         public function invalidateCache() {
4486                 global $wgMemc;
4487                 if ( wfReadOnly() ) {
4488                         return false;
4489                 }
4490                 $dbw = wfGetDB( DB_MASTER );
4491                 $success = $dbw->update(
4492                         'page',
4493                         array( 'page_touched' => $dbw->timestamp() ),
4494                         $this->pageCond(),
4495                         __METHOD__
4496                 );
4497                 HTMLFileCache::clearFileCache( $this );
4498
4499                 // Clear page info.
4500                 $revision = WikiPage::factory( $this )->getRevision();
4501                 if( $revision !== null ) {
4502                         $memcKey = wfMemcKey( 'infoaction', $this->getPrefixedText(), $revision->getId() );
4503                         $success = $success && $wgMemc->delete( $memcKey );
4504                 }
4505
4506                 return $success;
4507         }
4508
4509         /**
4510          * Update page_touched timestamps and send squid purge messages for
4511          * pages linking to this title. May be sent to the job queue depending
4512          * on the number of links. Typically called on create and delete.
4513          */
4514         public function touchLinks() {
4515                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
4516                 $u->doUpdate();
4517
4518                 if ( $this->getNamespace() == NS_CATEGORY ) {
4519                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
4520                         $u->doUpdate();
4521                 }
4522         }
4523
4524         /**
4525          * Get the last touched timestamp
4526          *
4527          * @param $db DatabaseBase: optional db
4528          * @return String last-touched timestamp
4529          */
4530         public function getTouched( $db = null ) {
4531                 $db = isset( $db ) ? $db : wfGetDB( DB_SLAVE );
4532                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
4533                 return $touched;
4534         }
4535
4536         /**
4537          * Get the timestamp when this page was updated since the user last saw it.
4538          *
4539          * @param $user User
4540          * @return String|Null
4541          */
4542         public function getNotificationTimestamp( $user = null ) {
4543                 global $wgUser, $wgShowUpdatedMarker;
4544                 // Assume current user if none given
4545                 if ( !$user ) {
4546                         $user = $wgUser;
4547                 }
4548                 // Check cache first
4549                 $uid = $user->getId();
4550                 // avoid isset here, as it'll return false for null entries
4551                 if ( array_key_exists( $uid, $this->mNotificationTimestamp ) ) {
4552                         return $this->mNotificationTimestamp[$uid];
4553                 }
4554                 if ( !$uid || !$wgShowUpdatedMarker ) {
4555                         return $this->mNotificationTimestamp[$uid] = false;
4556                 }
4557                 // Don't cache too much!
4558                 if ( count( $this->mNotificationTimestamp ) >= self::CACHE_MAX ) {
4559                         $this->mNotificationTimestamp = array();
4560                 }
4561                 $dbr = wfGetDB( DB_SLAVE );
4562                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
4563                         'wl_notificationtimestamp',
4564                         array(
4565                                 'wl_user' => $user->getId(),
4566                                 'wl_namespace' => $this->getNamespace(),
4567                                 'wl_title' => $this->getDBkey(),
4568                         ),
4569                         __METHOD__
4570                 );
4571                 return $this->mNotificationTimestamp[$uid];
4572         }
4573
4574         /**
4575          * Generate strings used for xml 'id' names in monobook tabs
4576          *
4577          * @param $prepend string defaults to 'nstab-'
4578          * @return String XML 'id' name
4579          */
4580         public function getNamespaceKey( $prepend = 'nstab-' ) {
4581                 global $wgContLang;
4582                 // Gets the subject namespace if this title
4583                 $namespace = MWNamespace::getSubject( $this->getNamespace() );
4584                 // Checks if cononical namespace name exists for namespace
4585                 if ( MWNamespace::exists( $this->getNamespace() ) ) {
4586                         // Uses canonical namespace name
4587                         $namespaceKey = MWNamespace::getCanonicalName( $namespace );
4588                 } else {
4589                         // Uses text of namespace
4590                         $namespaceKey = $this->getSubjectNsText();
4591                 }
4592                 // Makes namespace key lowercase
4593                 $namespaceKey = $wgContLang->lc( $namespaceKey );
4594                 // Uses main
4595                 if ( $namespaceKey == '' ) {
4596                         $namespaceKey = 'main';
4597                 }
4598                 // Changes file to image for backwards compatibility
4599                 if ( $namespaceKey == 'file' ) {
4600                         $namespaceKey = 'image';
4601                 }
4602                 return $prepend . $namespaceKey;
4603         }
4604
4605         /**
4606          * Get all extant redirects to this Title
4607          *
4608          * @param $ns Int|Null Single namespace to consider; NULL to consider all namespaces
4609          * @return Array of Title redirects to this title
4610          */
4611         public function getRedirectsHere( $ns = null ) {
4612                 $redirs = array();
4613
4614                 $dbr = wfGetDB( DB_SLAVE );
4615                 $where = array(
4616                         'rd_namespace' => $this->getNamespace(),
4617                         'rd_title' => $this->getDBkey(),
4618                         'rd_from = page_id'
4619                 );
4620                 if ( $this->isExternal() ) {
4621                         $where['rd_interwiki'] = $this->getInterwiki();
4622                 } else {
4623                         $where[] = 'rd_interwiki = ' . $dbr->addQuotes( '' ) . ' OR rd_interwiki IS NULL';
4624                 }
4625                 if ( !is_null( $ns ) ) {
4626                         $where['page_namespace'] = $ns;
4627                 }
4628
4629                 $res = $dbr->select(
4630                         array( 'redirect', 'page' ),
4631                         array( 'page_namespace', 'page_title' ),
4632                         $where,
4633                         __METHOD__
4634                 );
4635
4636                 foreach ( $res as $row ) {
4637                         $redirs[] = self::newFromRow( $row );
4638                 }
4639                 return $redirs;
4640         }
4641
4642         /**
4643          * Check if this Title is a valid redirect target
4644          *
4645          * @return Bool
4646          */
4647         public function isValidRedirectTarget() {
4648                 global $wgInvalidRedirectTargets;
4649
4650                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
4651                 if ( $this->isSpecial( 'Userlogout' ) ) {
4652                         return false;
4653                 }
4654
4655                 foreach ( $wgInvalidRedirectTargets as $target ) {
4656                         if ( $this->isSpecial( $target ) ) {
4657                                 return false;
4658                         }
4659                 }
4660
4661                 return true;
4662         }
4663
4664         /**
4665          * Get a backlink cache object
4666          *
4667          * @return BacklinkCache
4668          */
4669         public function getBacklinkCache() {
4670                 return BacklinkCache::get( $this );
4671         }
4672
4673         /**
4674          * Whether the magic words __INDEX__ and __NOINDEX__ function for  this page.
4675          *
4676          * @return Boolean
4677          */
4678         public function canUseNoindex() {
4679                 global $wgContentNamespaces, $wgExemptFromUserRobotsControl;
4680
4681                 $bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
4682                         ? $wgContentNamespaces
4683                         : $wgExemptFromUserRobotsControl;
4684
4685                 return !in_array( $this->mNamespace, $bannedNamespaces );
4686
4687         }
4688
4689         /**
4690          * Returns the raw sort key to be used for categories, with the specified
4691          * prefix.  This will be fed to Collation::getSortKey() to get a
4692          * binary sortkey that can be used for actual sorting.
4693          *
4694          * @param $prefix string The prefix to be used, specified using
4695          *   {{defaultsort:}} or like [[Category:Foo|prefix]].  Empty for no
4696          *   prefix.
4697          * @return string
4698          */
4699         public function getCategorySortkey( $prefix = '' ) {
4700                 $unprefixed = $this->getText();
4701
4702                 // Anything that uses this hook should only depend
4703                 // on the Title object passed in, and should probably
4704                 // tell the users to run updateCollations.php --force
4705                 // in order to re-sort existing category relations.
4706                 wfRunHooks( 'GetDefaultSortkey', array( $this, &$unprefixed ) );
4707                 if ( $prefix !== '' ) {
4708                         # Separate with a line feed, so the unprefixed part is only used as
4709                         # a tiebreaker when two pages have the exact same prefix.
4710                         # In UCA, tab is the only character that can sort above LF
4711                         # so we strip both of them from the original prefix.
4712                         $prefix = strtr( $prefix, "\n\t", '  ' );
4713                         return "$prefix\n$unprefixed";
4714                 }
4715                 return $unprefixed;
4716         }
4717
4718         /**
4719          * Get the language in which the content of this page is written in
4720          * wikitext. Defaults to $wgContLang, but in certain cases it can be
4721          * e.g. $wgLang (such as special pages, which are in the user language).
4722          *
4723          * @since 1.18
4724          * @return Language
4725          */
4726         public function getPageLanguage() {
4727                 global $wgLang;
4728                 if ( $this->isSpecialPage() ) {
4729                         // special pages are in the user language
4730                         return $wgLang;
4731                 }
4732
4733                 //TODO: use the LinkCache to cache this! Note that this may depend on user settings, so the cache should be only per-request.
4734                 //NOTE: ContentHandler::getPageLanguage() may need to load the content to determine the page language!
4735                 $contentHandler = ContentHandler::getForTitle( $this );
4736                 $pageLang = $contentHandler->getPageLanguage( $this );
4737
4738                 return wfGetLangObj( $pageLang );
4739         }
4740
4741         /**
4742          * Get the language in which the content of this page is written when
4743          * viewed by user. Defaults to $wgContLang, but in certain cases it can be
4744          * e.g. $wgLang (such as special pages, which are in the user language).
4745          *
4746          * @since 1.20
4747          * @return Language
4748          */
4749         public function getPageViewLanguage() {
4750                 global $wgLang;
4751
4752                 if ( $this->isSpecialPage() ) {
4753                         // If the user chooses a variant, the content is actually
4754                         // in a language whose code is the variant code.
4755                         $variant = $wgLang->getPreferredVariant();
4756                         if ( $wgLang->getCode() !== $variant ) {
4757                                 return Language::factory( $variant );
4758                         }
4759
4760                         return $wgLang;
4761                 }
4762
4763                 //NOTE: can't be cached persistently, depends on user settings
4764                 //NOTE: ContentHandler::getPageViewLanguage() may need to load the content to determine the page language!
4765                 $contentHandler = ContentHandler::getForTitle( $this );
4766                 $pageLang = $contentHandler->getPageViewLanguage( $this );
4767                 return $pageLang;
4768         }
4769
4770         /**
4771          * Get a list of rendered edit notices for this page.
4772          *
4773          * Array is keyed by the original message key, and values are rendered using parseAsBlock, so
4774          * they will already be wrapped in paragraphs.
4775          *
4776          * @since 1.21
4777          * @return Array
4778          */
4779         public function getEditNotices() {
4780                 $notices = array();
4781
4782                 # Optional notices on a per-namespace and per-page basis
4783                 $editnotice_ns = 'editnotice-' . $this->getNamespace();
4784                 $editnotice_ns_message = wfMessage( $editnotice_ns );
4785                 if ( $editnotice_ns_message->exists() ) {
4786                         $notices[$editnotice_ns] = $editnotice_ns_message->parseAsBlock();
4787                 }
4788                 if ( MWNamespace::hasSubpages( $this->getNamespace() ) ) {
4789                         $parts = explode( '/', $this->getDBkey() );
4790                         $editnotice_base = $editnotice_ns;
4791                         while ( count( $parts ) > 0 ) {
4792                                 $editnotice_base .= '-' . array_shift( $parts );
4793                                 $editnotice_base_msg = wfMessage( $editnotice_base );
4794                                 if ( $editnotice_base_msg->exists() ) {
4795                                         $notices[$editnotice_base] = $editnotice_base_msg->parseAsBlock();
4796                                 }
4797                         }
4798                 } else {
4799                         # Even if there are no subpages in namespace, we still don't want / in MW ns.
4800                         $editnoticeText = $editnotice_ns . '-' . str_replace( '/', '-', $this->getDBkey() );
4801                         $editnoticeMsg = wfMessage( $editnoticeText );
4802                         if ( $editnoticeMsg->exists() ) {
4803                                 $notices[$editnoticeText] = $editnoticeMsg->parseAsBlock();
4804                         }
4805                 }
4806                 return $notices;
4807         }
4808 }