includes/page/WikiPage.php

   1 <?php
   2 /**
   3  * Base representation for a MediaWiki page.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 /**
  24  * Abstract class for type hinting (accepts WikiPage, Article, ImagePage, CategoryPage)
  25  */
  26 interface Page {
  27 }
  28
  29 /**
  30  * Class representing a MediaWiki article and history.
  31  *
  32  * Some fields are public only for backwards-compatibility. Use accessors.
  33  * In the past, this class was part of Article.php and everything was public.
  34  */
  35 class WikiPage implements Page, IDBAccessObject {
  36         // Constants for $mDataLoadedFrom and related
  37
  38         /**
  39          * @var Title
  40          */
  41         public $mTitle = null;
  42
  43         /**@{{
  44          * @protected
  45          */
  46         public $mDataLoaded = false;         // !< Boolean
  47         public $mIsRedirect = false;         // !< Boolean
  48         public $mLatest = false;             // !< Integer (false means "not loaded")
  49         /**@}}*/
  50
  51         /** @var stdClass Map of cache fields (text, parser output, ect) for a proposed/new edit */
  52         public $mPreparedEdit = false;
  53
  54         /**
  55          * @var int
  56          */
  57         protected $mId = null;
  58
  59         /**
  60          * @var int One of the READ_* constants
  61          */
  62         protected $mDataLoadedFrom = self::READ_NONE;
  63
  64         /**
  65          * @var Title
  66          */
  67         protected $mRedirectTarget = null;
  68
  69         /**
  70          * @var Revision
  71          */
  72         protected $mLastRevision = null;
  73
  74         /**
  75          * @var string Timestamp of the current revision or empty string if not loaded
  76          */
  77         protected $mTimestamp = '';
  78
  79         /**
  80          * @var string
  81          */
  82         protected $mTouched = '19700101000000';
  83
  84         /**
  85          * @var string
  86          */
  87         protected $mLinksUpdated = '19700101000000';
  88
  89         /**
  90          * Constructor and clear the article
  91          * @param Title $title Reference to a Title object.
  92          */
  93         public function __construct( Title $title ) {
  94                 $this->mTitle = $title;
  95         }
  96
  97         /**
  98          * Create a WikiPage object of the appropriate class for the given title.
  99          *
 100          * @param Title $title
 101          *
 102          * @throws MWException
 103          * @return WikiPage Object of the appropriate type
 104          */
 105         public static function factory( Title $title ) {
 106                 $ns = $title->getNamespace();
 107
 108                 if ( $ns == NS_MEDIA ) {
 109                         throw new MWException( "NS_MEDIA is a virtual namespace; use NS_FILE." );
 110                 } elseif ( $ns < 0 ) {
 111                         throw new MWException( "Invalid or virtual namespace $ns given." );
 112                 }
 113
 114                 switch ( $ns ) {
 115                         case NS_FILE:
 116                                 $page = new WikiFilePage( $title );
 117                                 break;
 118                         case NS_CATEGORY:
 119                                 $page = new WikiCategoryPage( $title );
 120                                 break;
 121                         default:
 122                                 $page = new WikiPage( $title );
 123                 }
 124
 125                 return $page;
 126         }
 127
 128         /**
 129          * Constructor from a page id
 130          *
 131          * @param int $id Article ID to load
 132          * @param string|int $from One of the following values:
 133          *        - "fromdb" or WikiPage::READ_NORMAL to select from a slave database
 134          *        - "fromdbmaster" or WikiPage::READ_LATEST to select from the master database
 135          *
 136          * @return WikiPage|null
 137          */
 138         public static function newFromID( $id, $from = 'fromdb' ) {
 139                 // page id's are never 0 or negative, see bug 61166
 140                 if ( $id < 1 ) {
 141                         return null;
 142                 }
 143
 144                 $from = self::convertSelectType( $from );
 145                 $db = wfGetDB( $from === self::READ_LATEST ? DB_MASTER : DB_SLAVE );
 146                 $row = $db->selectRow( 'page', self::selectFields(), array( 'page_id' => $id ), __METHOD__ );
 147                 if ( !$row ) {
 148                         return null;
 149                 }
 150                 return self::newFromRow( $row, $from );
 151         }
 152
 153         /**
 154          * Constructor from a database row
 155          *
 156          * @since 1.20
 157          * @param object $row Database row containing at least fields returned by selectFields().
 158          * @param string|int $from Source of $data:
 159          *        - "fromdb" or WikiPage::READ_NORMAL: from a slave DB
 160          *        - "fromdbmaster" or WikiPage::READ_LATEST: from the master DB
 161          *        - "forupdate" or WikiPage::READ_LOCKING: from the master DB using SELECT FOR UPDATE
 162          * @return WikiPage
 163          */
 164         public static function newFromRow( $row, $from = 'fromdb' ) {
 165                 $page = self::factory( Title::newFromRow( $row ) );
 166                 $page->loadFromRow( $row, $from );
 167                 return $page;
 168         }
 169
 170         /**
 171          * Convert 'fromdb', 'fromdbmaster' and 'forupdate' to READ_* constants.
 172          *
 173          * @param object|string|int $type
 174          * @return mixed
 175          */
 176         private static function convertSelectType( $type ) {
 177                 switch ( $type ) {
 178                 case 'fromdb':
 179                         return self::READ_NORMAL;
 180                 case 'fromdbmaster':
 181                         return self::READ_LATEST;
 182                 case 'forupdate':
 183                         return self::READ_LOCKING;
 184                 default:
 185                         // It may already be an integer or whatever else
 186                         return $type;
 187                 }
 188         }
 189
 190         /**
 191          * Returns overrides for action handlers.
 192          * Classes listed here will be used instead of the default one when
 193          * (and only when) $wgActions[$action] === true. This allows subclasses
 194          * to override the default behavior.
 195          *
 196          * @todo Move this UI stuff somewhere else
 197          *
 198          * @return array
 199          */
 200         public function getActionOverrides() {
 201                 $content_handler = $this->getContentHandler();
 202                 return $content_handler->getActionOverrides();
 203         }
 204
 205         /**
 206          * Returns the ContentHandler instance to be used to deal with the content of this WikiPage.
 207          *
 208          * Shorthand for ContentHandler::getForModelID( $this->getContentModel() );
 209          *
 210          * @return ContentHandler
 211          *
 212          * @since 1.21
 213          */
 214         public function getContentHandler() {
 215                 return ContentHandler::getForModelID( $this->getContentModel() );
 216         }
 217
 218         /**
 219          * Get the title object of the article
 220          * @return Title Title object of this page
 221          */
 222         public function getTitle() {
 223                 return $this->mTitle;
 224         }
 225
 226         /**
 227          * Clear the object
 228          * @return void
 229          */
 230         public function clear() {
 231                 $this->mDataLoaded = false;
 232                 $this->mDataLoadedFrom = self::READ_NONE;
 233
 234                 $this->clearCacheFields();
 235         }
 236
 237         /**
 238          * Clear the object cache fields
 239          * @return void
 240          */
 241         protected function clearCacheFields() {
 242                 $this->mId = null;
 243                 $this->mRedirectTarget = null; // Title object if set
 244                 $this->mLastRevision = null; // Latest revision
 245                 $this->mTouched = '19700101000000';
 246                 $this->mLinksUpdated = '19700101000000';
 247                 $this->mTimestamp = '';
 248                 $this->mIsRedirect = false;
 249                 $this->mLatest = false;
 250                 // Bug 57026: do not clear mPreparedEdit since prepareTextForEdit() already checks
 251                 // the requested rev ID and content against the cached one for equality. For most
 252                 // content types, the output should not change during the lifetime of this cache.
 253                 // Clearing it can cause extra parses on edit for no reason.
 254         }
 255
 256         /**
 257          * Clear the mPreparedEdit cache field, as may be needed by mutable content types
 258          * @return void
 259          * @since 1.23
 260          */
 261         public function clearPreparedEdit() {
 262                 $this->mPreparedEdit = false;
 263         }
 264
 265         /**
 266          * Return the list of revision fields that should be selected to create
 267          * a new page.
 268          *
 269          * @return array
 270          */
 271         public static function selectFields() {
 272                 global $wgContentHandlerUseDB, $wgPageLanguageUseDB;
 273
 274                 $fields = array(
 275                         'page_id',
 276                         'page_namespace',
 277                         'page_title',
 278                         'page_restrictions',
 279                         'page_is_redirect',
 280                         'page_is_new',
 281                         'page_random',
 282                         'page_touched',
 283                         'page_links_updated',
 284                         'page_latest',
 285                         'page_len',
 286                 );
 287
 288                 if ( $wgContentHandlerUseDB ) {
 289                         $fields[] = 'page_content_model';
 290                 }
 291
 292                 if ( $wgPageLanguageUseDB ) {
 293                         $fields[] = 'page_lang';
 294                 }
 295
 296                 return $fields;
 297         }
 298
 299         /**
 300          * Fetch a page record with the given conditions
 301          * @param DatabaseBase $dbr
 302          * @param array $conditions
 303          * @param array $options
 304          * @return object|bool Database result resource, or false on failure
 305          */
 306         protected function pageData( $dbr, $conditions, $options = array() ) {
 307                 $fields = self::selectFields();
 308
 309                 Hooks::run( 'ArticlePageDataBefore', array( &$this, &$fields ) );
 310
 311                 $row = $dbr->selectRow( 'page', $fields, $conditions, __METHOD__, $options );
 312
 313                 Hooks::run( 'ArticlePageDataAfter', array( &$this, &$row ) );
 314
 315                 return $row;
 316         }
 317
 318         /**
 319          * Fetch a page record matching the Title object's namespace and title
 320          * using a sanitized title string
 321          *
 322          * @param DatabaseBase $dbr
 323          * @param Title $title
 324          * @param array $options
 325          * @return object|bool Database result resource, or false on failure
 326          */
 327         public function pageDataFromTitle( $dbr, $title, $options = array() ) {
 328                 return $this->pageData( $dbr, array(
 329                         'page_namespace' => $title->getNamespace(),
 330                         'page_title' => $title->getDBkey() ), $options );
 331         }
 332
 333         /**
 334          * Fetch a page record matching the requested ID
 335          *
 336          * @param DatabaseBase $dbr
 337          * @param int $id
 338          * @param array $options
 339          * @return object|bool Database result resource, or false on failure
 340          */
 341         public function pageDataFromId( $dbr, $id, $options = array() ) {
 342                 return $this->pageData( $dbr, array( 'page_id' => $id ), $options );
 343         }
 344
 345         /**
 346          * Load the object from a given source by title
 347          *
 348          * @param object|string|int $from One of the following:
 349          *   - A DB query result object.
 350          *   - "fromdb" or WikiPage::READ_NORMAL to get from a slave DB.
 351          *   - "fromdbmaster" or WikiPage::READ_LATEST to get from the master DB.
 352          *   - "forupdate"  or WikiPage::READ_LOCKING to get from the master DB
 353          *     using SELECT FOR UPDATE.
 354          *
 355          * @return void
 356          */
 357         public function loadPageData( $from = 'fromdb' ) {
 358                 $from = self::convertSelectType( $from );
 359                 if ( is_int( $from ) && $from <= $this->mDataLoadedFrom ) {
 360                         // We already have the data from the correct location, no need to load it twice.
 361                         return;
 362                 }
 363
 364                 if ( $from === self::READ_LOCKING ) {
 365                         $data = $this->pageDataFromTitle( wfGetDB( DB_MASTER ), $this->mTitle, array( 'FOR UPDATE' ) );
 366                 } elseif ( $from === self::READ_LATEST ) {
 367                         $data = $this->pageDataFromTitle( wfGetDB( DB_MASTER ), $this->mTitle );
 368                 } elseif ( $from === self::READ_NORMAL ) {
 369                         $data = $this->pageDataFromTitle( wfGetDB( DB_SLAVE ), $this->mTitle );
 370                         if ( !$data
 371                                 && wfGetLB()->getServerCount() > 1
 372                                 && wfGetLB()->hasOrMadeRecentMasterChanges()
 373                         ) {
 374                                 $from = self::READ_LATEST;
 375                                 $data = $this->pageDataFromTitle( wfGetDB( DB_MASTER ), $this->mTitle );
 376                         }
 377                 } else {
 378                         // No idea from where the caller got this data, assume slave database.
 379                         $data = $from;
 380                         $from = self::READ_NORMAL;
 381                 }
 382
 383                 $this->loadFromRow( $data, $from );
 384         }
 385
 386         /**
 387          * Load the object from a database row
 388          *
 389          * @since 1.20
 390          * @param object $data Database row containing at least fields returned by selectFields()
 391          * @param string|int $from One of the following:
 392          *        - "fromdb" or WikiPage::READ_NORMAL if the data comes from a slave DB
 393          *        - "fromdbmaster" or WikiPage::READ_LATEST if the data comes from the master DB
 394          *        - "forupdate"  or WikiPage::READ_LOCKING if the data comes from
 395          *          the master DB using SELECT FOR UPDATE
 396          */
 397         public function loadFromRow( $data, $from ) {
 398                 $lc = LinkCache::singleton();
 399                 $lc->clearLink( $this->mTitle );
 400
 401                 if ( $data ) {
 402                         $lc->addGoodLinkObjFromRow( $this->mTitle, $data );
 403
 404                         $this->mTitle->loadFromRow( $data );
 405
 406                         // Old-fashioned restrictions
 407                         $this->mTitle->loadRestrictions( $data->page_restrictions );
 408
 409                         $this->mId = intval( $data->page_id );
 410                         $this->mTouched = wfTimestamp( TS_MW, $data->page_touched );
 411                         $this->mLinksUpdated = wfTimestampOrNull( TS_MW, $data->page_links_updated );
 412                         $this->mIsRedirect = intval( $data->page_is_redirect );
 413                         $this->mLatest = intval( $data->page_latest );
 414                         // Bug 37225: $latest may no longer match the cached latest Revision object.
 415                         // Double-check the ID of any cached latest Revision object for consistency.
 416                         if ( $this->mLastRevision && $this->mLastRevision->getId() != $this->mLatest ) {
 417                                 $this->mLastRevision = null;
 418                                 $this->mTimestamp = '';
 419                         }
 420                 } else {
 421                         $lc->addBadLinkObj( $this->mTitle );
 422
 423                         $this->mTitle->loadFromRow( false );
 424
 425                         $this->clearCacheFields();
 426
 427                         $this->mId = 0;
 428                 }
 429
 430                 $this->mDataLoaded = true;
 431                 $this->mDataLoadedFrom = self::convertSelectType( $from );
 432         }
 433
 434         /**
 435          * @return int Page ID
 436          */
 437         public function getId() {
 438                 if ( !$this->mDataLoaded ) {
 439                         $this->loadPageData();
 440                 }
 441                 return $this->mId;
 442         }
 443
 444         /**
 445          * @return bool Whether or not the page exists in the database
 446          */
 447         public function exists() {
 448                 if ( !$this->mDataLoaded ) {
 449                         $this->loadPageData();
 450                 }
 451                 return $this->mId > 0;
 452         }
 453
 454         /**
 455          * Check if this page is something we're going to be showing
 456          * some sort of sensible content for. If we return false, page
 457          * views (plain action=view) will return an HTTP 404 response,
 458          * so spiders and robots can know they're following a bad link.
 459          *
 460          * @return bool
 461          */
 462         public function hasViewableContent() {
 463                 return $this->exists() || $this->mTitle->isAlwaysKnown();
 464         }
 465
 466         /**
 467          * Tests if the article content represents a redirect
 468          *
 469          * @return bool
 470          */
 471         public function isRedirect() {
 472                 $content = $this->getContent();
 473                 if ( !$content ) {
 474                         return false;
 475                 }
 476
 477                 return $content->isRedirect();
 478         }
 479
 480         /**
 481          * Returns the page's content model id (see the CONTENT_MODEL_XXX constants).
 482          *
 483          * Will use the revisions actual content model if the page exists,
 484          * and the page's default if the page doesn't exist yet.
 485          *
 486          * @return string
 487          *
 488          * @since 1.21
 489          */
 490         public function getContentModel() {
 491                 if ( $this->exists() ) {
 492                         // look at the revision's actual content model
 493                         $rev = $this->getRevision();
 494
 495                         if ( $rev !== null ) {
 496                                 return $rev->getContentModel();
 497                         } else {
 498                                 $title = $this->mTitle->getPrefixedDBkey();
 499                                 wfWarn( "Page $title exists but has no (visible) revisions!" );
 500                         }
 501                 }
 502
 503                 // use the default model for this page
 504                 return $this->mTitle->getContentModel();
 505         }
 506
 507         /**
 508          * Loads page_touched and returns a value indicating if it should be used
 509          * @return bool True if not a redirect
 510          */
 511         public function checkTouched() {
 512                 if ( !$this->mDataLoaded ) {
 513                         $this->loadPageData();
 514                 }
 515                 return !$this->mIsRedirect;
 516         }
 517
 518         /**
 519          * Get the page_touched field
 520          * @return string Containing GMT timestamp
 521          */
 522         public function getTouched() {
 523                 if ( !$this->mDataLoaded ) {
 524                         $this->loadPageData();
 525                 }
 526                 return $this->mTouched;
 527         }
 528
 529         /**
 530          * Get the page_links_updated field
 531          * @return string|null Containing GMT timestamp
 532          */
 533         public function getLinksTimestamp() {
 534                 if ( !$this->mDataLoaded ) {
 535                         $this->loadPageData();
 536                 }
 537                 return $this->mLinksUpdated;
 538         }
 539
 540         /**
 541          * Get the page_latest field
 542          * @return int The rev_id of current revision
 543          */
 544         public function getLatest() {
 545                 if ( !$this->mDataLoaded ) {
 546                         $this->loadPageData();
 547                 }
 548                 return (int)$this->mLatest;
 549         }
 550
 551         /**
 552          * Get the Revision object of the oldest revision
 553          * @return Revision|null
 554          */
 555         public function getOldestRevision() {
 556
 557                 // Try using the slave database first, then try the master
 558                 $continue = 2;
 559                 $db = wfGetDB( DB_SLAVE );
 560                 $revSelectFields = Revision::selectFields();
 561
 562                 $row = null;
 563                 while ( $continue ) {
 564                         $row = $db->selectRow(
 565                                 array( 'page', 'revision' ),
 566                                 $revSelectFields,
 567                                 array(
 568                                         'page_namespace' => $this->mTitle->getNamespace(),
 569                                         'page_title' => $this->mTitle->getDBkey(),
 570                                         'rev_page = page_id'
 571                                 ),
 572                                 __METHOD__,
 573                                 array(
 574                                         'ORDER BY' => 'rev_timestamp ASC'
 575                                 )
 576                         );
 577
 578                         if ( $row ) {
 579                                 $continue = 0;
 580                         } else {
 581                                 $db = wfGetDB( DB_MASTER );
 582                                 $continue--;
 583                         }
 584                 }
 585
 586                 return $row ? Revision::newFromRow( $row ) : null;
 587         }
 588
 589         /**
 590          * Loads everything except the text
 591          * This isn't necessary for all uses, so it's only done if needed.
 592          */
 593         protected function loadLastEdit() {
 594                 if ( $this->mLastRevision !== null ) {
 595                         return; // already loaded
 596                 }
 597
 598                 $latest = $this->getLatest();
 599                 if ( !$latest ) {
 600                         return; // page doesn't exist or is missing page_latest info
 601                 }
 602
 603                 if ( $this->mDataLoadedFrom == self::READ_LOCKING ) {
 604                         // Bug 37225: if session S1 loads the page row FOR UPDATE, the result always
 605                         // includes the latest changes committed. This is true even within REPEATABLE-READ
 606                         // transactions, where S1 normally only sees changes committed before the first S1
 607                         // SELECT. Thus we need S1 to also gets the revision row FOR UPDATE; otherwise, it
 608                         // may not find it since a page row UPDATE and revision row INSERT by S2 may have
 609                         // happened after the first S1 SELECT.
 610                         // http://dev.mysql.com/doc/refman/5.0/en/set-transaction.html#isolevel_repeatable-read.
 611                         $flags = Revision::READ_LOCKING;
 612                 } elseif ( $this->mDataLoadedFrom == self::READ_LATEST ) {
 613                         // Bug T93976: if page_latest was loaded from the master, fetch the
 614                         // revision from there as well, as it may not exist yet on a slave DB.
 615                         // Also, this keeps the queries in the same REPEATABLE-READ snapshot.
 616                         $flags = Revision::READ_LATEST;
 617                 } else {
 618                         $flags = 0;
 619                 }
 620                 $revision = Revision::newFromPageId( $this->getId(), $latest, $flags );
 621                 if ( $revision ) { // sanity
 622                         $this->setLastEdit( $revision );
 623                 }
 624         }
 625
 626         /**
 627          * Set the latest revision
 628          * @param Revision $revision
 629          */
 630         protected function setLastEdit( Revision $revision ) {
 631                 $this->mLastRevision = $revision;
 632                 $this->mTimestamp = $revision->getTimestamp();
 633         }
 634
 635         /**
 636          * Get the latest revision
 637          * @return Revision|null
 638          */
 639         public function getRevision() {
 640                 $this->loadLastEdit();
 641                 if ( $this->mLastRevision ) {
 642                         return $this->mLastRevision;
 643                 }
 644                 return null;
 645         }
 646
 647         /**
 648          * Get the content of the current revision. No side-effects...
 649          *
 650          * @param int $audience One of:
 651          *   Revision::FOR_PUBLIC       to be displayed to all users
 652          *   Revision::FOR_THIS_USER    to be displayed to $wgUser
 653          *   Revision::RAW              get the text regardless of permissions
 654          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 655          *   to the $audience parameter
 656          * @return Content|null The content of the current revision
 657          *
 658          * @since 1.21
 659          */
 660         public function getContent( $audience = Revision::FOR_PUBLIC, User $user = null ) {
 661                 $this->loadLastEdit();
 662                 if ( $this->mLastRevision ) {
 663                         return $this->mLastRevision->getContent( $audience, $user );
 664                 }
 665                 return null;
 666         }
 667
 668         /**
 669          * Get the text of the current revision. No side-effects...
 670          *
 671          * @param int $audience One of:
 672          *   Revision::FOR_PUBLIC       to be displayed to all users
 673          *   Revision::FOR_THIS_USER    to be displayed to the given user
 674          *   Revision::RAW              get the text regardless of permissions
 675          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 676          *   to the $audience parameter
 677          * @return string|bool The text of the current revision
 678          * @deprecated since 1.21, getContent() should be used instead.
 679          */
 680         public function getText( $audience = Revision::FOR_PUBLIC, User $user = null ) {
 681                 ContentHandler::deprecated( __METHOD__, '1.21' );
 682
 683                 $this->loadLastEdit();
 684                 if ( $this->mLastRevision ) {
 685                         return $this->mLastRevision->getText( $audience, $user );
 686                 }
 687                 return false;
 688         }
 689
 690         /**
 691          * Get the text of the current revision. No side-effects...
 692          *
 693          * @return string|bool The text of the current revision. False on failure
 694          * @deprecated since 1.21, getContent() should be used instead.
 695          */
 696         public function getRawText() {
 697                 ContentHandler::deprecated( __METHOD__, '1.21' );
 698
 699                 return $this->getText( Revision::RAW );
 700         }
 701
 702         /**
 703          * @return string MW timestamp of last article revision
 704          */
 705         public function getTimestamp() {
 706                 // Check if the field has been filled by WikiPage::setTimestamp()
 707                 if ( !$this->mTimestamp ) {
 708                         $this->loadLastEdit();
 709                 }
 710
 711                 return wfTimestamp( TS_MW, $this->mTimestamp );
 712         }
 713
 714         /**
 715          * Set the page timestamp (use only to avoid DB queries)
 716          * @param string $ts MW timestamp of last article revision
 717          * @return void
 718          */
 719         public function setTimestamp( $ts ) {
 720                 $this->mTimestamp = wfTimestamp( TS_MW, $ts );
 721         }
 722
 723         /**
 724          * @param int $audience One of:
 725          *   Revision::FOR_PUBLIC       to be displayed to all users
 726          *   Revision::FOR_THIS_USER    to be displayed to the given user
 727          *   Revision::RAW              get the text regardless of permissions
 728          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 729          *   to the $audience parameter
 730          * @return int User ID for the user that made the last article revision
 731          */
 732         public function getUser( $audience = Revision::FOR_PUBLIC, User $user = null ) {
 733                 $this->loadLastEdit();
 734                 if ( $this->mLastRevision ) {
 735                         return $this->mLastRevision->getUser( $audience, $user );
 736                 } else {
 737                         return -1;
 738                 }
 739         }
 740
 741         /**
 742          * Get the User object of the user who created the page
 743          * @param int $audience One of:
 744          *   Revision::FOR_PUBLIC       to be displayed to all users
 745          *   Revision::FOR_THIS_USER    to be displayed to the given user
 746          *   Revision::RAW              get the text regardless of permissions
 747          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 748          *   to the $audience parameter
 749          * @return User|null
 750          */
 751         public function getCreator( $audience = Revision::FOR_PUBLIC, User $user = null ) {
 752                 $revision = $this->getOldestRevision();
 753                 if ( $revision ) {
 754                         $userName = $revision->getUserText( $audience, $user );
 755                         return User::newFromName( $userName, false );
 756                 } else {
 757                         return null;
 758                 }
 759         }
 760
 761         /**
 762          * @param int $audience One of:
 763          *   Revision::FOR_PUBLIC       to be displayed to all users
 764          *   Revision::FOR_THIS_USER    to be displayed to the given user
 765          *   Revision::RAW              get the text regardless of permissions
 766          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 767          *   to the $audience parameter
 768          * @return string Username of the user that made the last article revision
 769          */
 770         public function getUserText( $audience = Revision::FOR_PUBLIC, User $user = null ) {
 771                 $this->loadLastEdit();
 772                 if ( $this->mLastRevision ) {
 773                         return $this->mLastRevision->getUserText( $audience, $user );
 774                 } else {
 775                         return '';
 776                 }
 777         }
 778
 779         /**
 780          * @param int $audience One of:
 781          *   Revision::FOR_PUBLIC       to be displayed to all users
 782          *   Revision::FOR_THIS_USER    to be displayed to the given user
 783          *   Revision::RAW              get the text regardless of permissions
 784          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 785          *   to the $audience parameter
 786          * @return string Comment stored for the last article revision
 787          */
 788         public function getComment( $audience = Revision::FOR_PUBLIC, User $user = null ) {
 789                 $this->loadLastEdit();
 790                 if ( $this->mLastRevision ) {
 791                         return $this->mLastRevision->getComment( $audience, $user );
 792                 } else {
 793                         return '';
 794                 }
 795         }
 796
 797         /**
 798          * Returns true if last revision was marked as "minor edit"
 799          *
 800          * @return bool Minor edit indicator for the last article revision.
 801          */
 802         public function getMinorEdit() {
 803                 $this->loadLastEdit();
 804                 if ( $this->mLastRevision ) {
 805                         return $this->mLastRevision->isMinor();
 806                 } else {
 807                         return false;
 808                 }
 809         }
 810
 811         /**
 812          * Determine whether a page would be suitable for being counted as an
 813          * article in the site_stats table based on the title & its content
 814          *
 815          * @param object|bool $editInfo (false): object returned by prepareTextForEdit(),
 816          *   if false, the current database state will be used
 817          * @return bool
 818          */
 819         public function isCountable( $editInfo = false ) {
 820                 global $wgArticleCountMethod;
 821
 822                 if ( !$this->mTitle->isContentPage() ) {
 823                         return false;
 824                 }
 825
 826                 if ( $editInfo ) {
 827                         $content = $editInfo->pstContent;
 828                 } else {
 829                         $content = $this->getContent();
 830                 }
 831
 832                 if ( !$content || $content->isRedirect() ) {
 833                         return false;
 834                 }
 835
 836                 $hasLinks = null;
 837
 838                 if ( $wgArticleCountMethod === 'link' ) {
 839                         // nasty special case to avoid re-parsing to detect links
 840
 841                         if ( $editInfo ) {
 842                                 // ParserOutput::getLinks() is a 2D array of page links, so
 843                                 // to be really correct we would need to recurse in the array
 844                                 // but the main array should only have items in it if there are
 845                                 // links.
 846                                 $hasLinks = (bool)count( $editInfo->output->getLinks() );
 847                         } else {
 848                                 $hasLinks = (bool)wfGetDB( DB_SLAVE )->selectField( 'pagelinks', 1,
 849                                         array( 'pl_from' => $this->getId() ), __METHOD__ );
 850                         }
 851                 }
 852
 853                 return $content->isCountable( $hasLinks );
 854         }
 855
 856         /**
 857          * If this page is a redirect, get its target
 858          *
 859          * The target will be fetched from the redirect table if possible.
 860          * If this page doesn't have an entry there, call insertRedirect()
 861          * @return Title|null Title object, or null if this page is not a redirect
 862          */
 863         public function getRedirectTarget() {
 864                 if ( !$this->mTitle->isRedirect() ) {
 865                         return null;
 866                 }
 867
 868                 if ( $this->mRedirectTarget !== null ) {
 869                         return $this->mRedirectTarget;
 870                 }
 871
 872                 // Query the redirect table
 873                 $dbr = wfGetDB( DB_SLAVE );
 874                 $row = $dbr->selectRow( 'redirect',
 875                         array( 'rd_namespace', 'rd_title', 'rd_fragment', 'rd_interwiki' ),
 876                         array( 'rd_from' => $this->getId() ),
 877                         __METHOD__
 878                 );
 879
 880                 // rd_fragment and rd_interwiki were added later, populate them if empty
 881                 if ( $row && !is_null( $row->rd_fragment ) && !is_null( $row->rd_interwiki ) ) {
 882                         $this->mRedirectTarget = Title::makeTitle(
 883                                 $row->rd_namespace, $row->rd_title,
 884                                 $row->rd_fragment, $row->rd_interwiki );
 885                         return $this->mRedirectTarget;
 886                 }
 887
 888                 // This page doesn't have an entry in the redirect table
 889                 $this->mRedirectTarget = $this->insertRedirect();
 890                 return $this->mRedirectTarget;
 891         }
 892
 893         /**
 894          * Insert an entry for this page into the redirect table.
 895          *
 896          * Don't call this function directly unless you know what you're doing.
 897          * @return Title|null Title object or null if not a redirect
 898          */
 899         public function insertRedirect() {
 900                 // recurse through to only get the final target
 901                 $content = $this->getContent();
 902                 $retval = $content ? $content->getUltimateRedirectTarget() : null;
 903                 if ( !$retval ) {
 904                         return null;
 905                 }
 906                 $this->insertRedirectEntry( $retval );
 907                 return $retval;
 908         }
 909
 910         /**
 911          * Insert or update the redirect table entry for this page to indicate
 912          * it redirects to $rt .
 913          * @param Title $rt Redirect target
 914          */
 915         public function insertRedirectEntry( $rt ) {
 916                 $dbw = wfGetDB( DB_MASTER );
 917                 $dbw->replace( 'redirect', array( 'rd_from' ),
 918                         array(
 919                                 'rd_from' => $this->getId(),
 920                                 'rd_namespace' => $rt->getNamespace(),
 921                                 'rd_title' => $rt->getDBkey(),
 922                                 'rd_fragment' => $rt->getFragment(),
 923                                 'rd_interwiki' => $rt->getInterwiki(),
 924                         ),
 925                         __METHOD__
 926                 );
 927         }
 928
 929         /**
 930          * Get the Title object or URL this page redirects to
 931          *
 932          * @return bool|Title|string False, Title of in-wiki target, or string with URL
 933          */
 934         public function followRedirect() {
 935                 return $this->getRedirectURL( $this->getRedirectTarget() );
 936         }
 937
 938         /**
 939          * Get the Title object or URL to use for a redirect. We use Title
 940          * objects for same-wiki, non-special redirects and URLs for everything
 941          * else.
 942          * @param Title $rt Redirect target
 943          * @return bool|Title|string False, Title object of local target, or string with URL
 944          */
 945         public function getRedirectURL( $rt ) {
 946                 if ( !$rt ) {
 947                         return false;
 948                 }
 949
 950                 if ( $rt->isExternal() ) {
 951                         if ( $rt->isLocal() ) {
 952                                 // Offsite wikis need an HTTP redirect.
 953                                 //
 954                                 // This can be hard to reverse and may produce loops,
 955                                 // so they may be disabled in the site configuration.
 956                                 $source = $this->mTitle->getFullURL( 'redirect=no' );
 957                                 return $rt->getFullURL( array( 'rdfrom' => $source ) );
 958                         } else {
 959                                 // External pages without "local" bit set are not valid
 960                                 // redirect targets
 961                                 return false;
 962                         }
 963                 }
 964
 965                 if ( $rt->isSpecialPage() ) {
 966                         // Gotta handle redirects to special pages differently:
 967                         // Fill the HTTP response "Location" header and ignore
 968                         // the rest of the page we're on.
 969                         //
 970                         // Some pages are not valid targets
 971                         if ( $rt->isValidRedirectTarget() ) {
 972                                 return $rt->getFullURL();
 973                         } else {
 974                                 return false;
 975                         }
 976                 }
 977
 978                 return $rt;
 979         }
 980
 981         /**
 982          * Get a list of users who have edited this article, not including the user who made
 983          * the most recent revision, which you can get from $article->getUser() if you want it
 984          * @return UserArrayFromResult
 985          */
 986         public function getContributors() {
 987                 // @todo FIXME: This is expensive; cache this info somewhere.
 988
 989                 $dbr = wfGetDB( DB_SLAVE );
 990
 991                 if ( $dbr->implicitGroupby() ) {
 992                         $realNameField = 'user_real_name';
 993                 } else {
 994                         $realNameField = 'MIN(user_real_name) AS user_real_name';
 995                 }
 996
 997                 $tables = array( 'revision', 'user' );
 998
 999                 $fields = array(
1000                         'user_id' => 'rev_user',
1001                         'user_name' => 'rev_user_text',
1002                         $realNameField,
1003                         'timestamp' => 'MAX(rev_timestamp)',
1004                 );
1005
1006                 $conds = array( 'rev_page' => $this->getId() );
1007
1008                 // The user who made the top revision gets credited as "this page was last edited by
1009                 // John, based on contributions by Tom, Dick and Harry", so don't include them twice.
1010                 $user = $this->getUser();
1011                 if ( $user ) {
1012                         $conds[] = "rev_user != $user";
1013                 } else {
1014                         $conds[] = "rev_user_text != {$dbr->addQuotes( $this->getUserText() )}";
1015                 }
1016
1017                 $conds[] = "{$dbr->bitAnd( 'rev_deleted', Revision::DELETED_USER )} = 0"; // username hidden?
1018
1019                 $jconds = array(
1020                         'user' => array( 'LEFT JOIN', 'rev_user = user_id' ),
1021                 );
1022
1023                 $options = array(
1024                         'GROUP BY' => array( 'rev_user', 'rev_user_text' ),
1025                         'ORDER BY' => 'timestamp DESC',
1026                 );
1027
1028                 $res = $dbr->select( $tables, $fields, $conds, __METHOD__, $options, $jconds );
1029                 return new UserArrayFromResult( $res );
1030         }
1031
1032         /**
1033          * Get the last N authors
1034          * @param int $num Number of revisions to get
1035          * @param int|string $revLatest The latest rev_id, selected from the master (optional)
1036          * @return array Array of authors, duplicates not removed
1037          */
1038         public function getLastNAuthors( $num, $revLatest = 0 ) {
1039                 // First try the slave
1040                 // If that doesn't have the latest revision, try the master
1041                 $continue = 2;
1042                 $db = wfGetDB( DB_SLAVE );
1043
1044                 do {
1045                         $res = $db->select( array( 'page', 'revision' ),
1046                                 array( 'rev_id', 'rev_user_text' ),
1047                                 array(
1048                                         'page_namespace' => $this->mTitle->getNamespace(),
1049                                         'page_title' => $this->mTitle->getDBkey(),
1050                                         'rev_page = page_id'
1051                                 ), __METHOD__,
1052                                 array(
1053                                         'ORDER BY' => 'rev_timestamp DESC',
1054                                         'LIMIT' => $num
1055                                 )
1056                         );
1057
1058                         if ( !$res ) {
1059                                 return array();
1060                         }
1061
1062                         $row = $db->fetchObject( $res );
1063
1064                         if ( $continue == 2 && $revLatest && $row->rev_id != $revLatest ) {
1065                                 $db = wfGetDB( DB_MASTER );
1066                                 $continue--;
1067                         } else {
1068                                 $continue = 0;
1069                         }
1070                 } while ( $continue );
1071
1072                 $authors = array( $row->rev_user_text );
1073
1074                 foreach ( $res as $row ) {
1075                         $authors[] = $row->rev_user_text;
1076                 }
1077
1078                 return $authors;
1079         }
1080
1081         /**
1082          * Should the parser cache be used?
1083          *
1084          * @param ParserOptions $parserOptions ParserOptions to check
1085          * @param int $oldid
1086          * @return bool
1087          */
1088         public function isParserCacheUsed( ParserOptions $parserOptions, $oldid ) {
1089                 global $wgEnableParserCache;
1090
1091                 return $wgEnableParserCache
1092                         && $parserOptions->getStubThreshold() == 0
1093                         && $this->exists()
1094                         && ( $oldid === null || $oldid === 0 || $oldid === $this->getLatest() )
1095                         && $this->getContentHandler()->isParserCacheSupported();
1096         }
1097
1098         /**
1099          * Get a ParserOutput for the given ParserOptions and revision ID.
1100          * The parser cache will be used if possible.
1101          *
1102          * @since 1.19
1103          * @param ParserOptions $parserOptions ParserOptions to use for the parse operation
1104          * @param null|int $oldid Revision ID to get the text from, passing null or 0 will
1105          *   get the current revision (default value)
1106          *
1107          * @return ParserOutput|bool ParserOutput or false if the revision was not found
1108          */
1109         public function getParserOutput( ParserOptions $parserOptions, $oldid = null ) {
1110
1111                 $useParserCache = $this->isParserCacheUsed( $parserOptions, $oldid );
1112                 wfDebug( __METHOD__ . ': using parser cache: ' . ( $useParserCache ? 'yes' : 'no' ) . "\n" );
1113                 if ( $parserOptions->getStubThreshold() ) {
1114                         wfIncrStats( 'pcache_miss_stub' );
1115                 }
1116
1117                 if ( $useParserCache ) {
1118                         $parserOutput = ParserCache::singleton()->get( $this, $parserOptions );
1119                         if ( $parserOutput !== false ) {
1120                                 return $parserOutput;
1121                         }
1122                 }
1123
1124                 if ( $oldid === null || $oldid === 0 ) {
1125                         $oldid = $this->getLatest();
1126                 }
1127
1128                 $pool = new PoolWorkArticleView( $this, $parserOptions, $oldid, $useParserCache );
1129                 $pool->execute();
1130
1131                 return $pool->getParserOutput();
1132         }
1133
1134         /**
1135          * Do standard deferred updates after page view (existing or missing page)
1136          * @param User $user The relevant user
1137          * @param int $oldid The revision id being viewed. If not given or 0, latest revision is assumed.
1138          */
1139         public function doViewUpdates( User $user, $oldid = 0 ) {
1140                 if ( wfReadOnly() ) {
1141                         return;
1142                 }
1143
1144                 Hooks::run( 'PageViewUpdates', array( $this, $user ) );
1145                 // Update newtalk / watchlist notification status
1146                 try {
1147                         $user->clearNotification( $this->mTitle, $oldid );
1148                 } catch ( DBError $e ) {
1149                         // Avoid outage if the master is not reachable
1150                         MWExceptionHandler::logException( $e );
1151                 }
1152         }
1153
1154         /**
1155          * Perform the actions of a page purging
1156          * @return bool
1157          */
1158         public function doPurge() {
1159                 if ( !Hooks::run( 'ArticlePurge', array( &$this ) ) ) {
1160                         return false;
1161                 }
1162
1163                 $title = $this->mTitle;
1164                 wfGetDB( DB_MASTER )->onTransactionIdle( function() use ( $title ) {
1165                         global $wgUseSquid;
1166                         // Invalidate the cache in auto-commit mode
1167                         $title->invalidateCache();
1168                         if ( $wgUseSquid ) {
1169                                 // Send purge now that page_touched update was committed above
1170                                 $update = SquidUpdate::newSimplePurge( $title );
1171                                 $update->doUpdate();
1172                         }
1173                 } );
1174
1175                 if ( $this->mTitle->getNamespace() == NS_MEDIAWIKI ) {
1176                         // @todo move this logic to MessageCache
1177                         if ( $this->exists() ) {
1178                                 // NOTE: use transclusion text for messages.
1179                                 //       This is consistent with  MessageCache::getMsgFromNamespace()
1180
1181                                 $content = $this->getContent();
1182                                 $text = $content === null ? null : $content->getWikitextForTransclusion();
1183
1184                                 if ( $text === null ) {
1185                                         $text = false;
1186                                 }
1187                         } else {
1188                                 $text = false;
1189                         }
1190
1191                         MessageCache::singleton()->replace( $this->mTitle->getDBkey(), $text );
1192                 }
1193
1194                 return true;
1195         }
1196
1197         /**
1198          * Insert a new empty page record for this article.
1199          * This *must* be followed up by creating a revision
1200          * and running $this->updateRevisionOn( ... );
1201          * or else the record will be left in a funky state.
1202          * Best if all done inside a transaction.
1203          *
1204          * @param DatabaseBase $dbw
1205          * @return int The newly created page_id key, or false if the title already existed
1206          */
1207         public function insertOn( $dbw ) {
1208
1209                 $page_id = $dbw->nextSequenceValue( 'page_page_id_seq' );
1210                 $dbw->insert( 'page', array(
1211                         'page_id'           => $page_id,
1212                         'page_namespace'    => $this->mTitle->getNamespace(),
1213                         'page_title'        => $this->mTitle->getDBkey(),
1214                         'page_restrictions' => '',
1215                         'page_is_redirect'  => 0, // Will set this shortly...
1216                         'page_is_new'       => 1,
1217                         'page_random'       => wfRandom(),
1218                         'page_touched'      => $dbw->timestamp(),
1219                         'page_latest'       => 0, // Fill this in shortly...
1220                         'page_len'          => 0, // Fill this in shortly...
1221                 ), __METHOD__, 'IGNORE' );
1222
1223                 $affected = $dbw->affectedRows();
1224
1225                 if ( $affected ) {
1226                         $newid = $dbw->insertId();
1227                         $this->mId = $newid;
1228                         $this->mTitle->resetArticleID( $newid );
1229                 }
1230
1231                 return $affected ? $newid : false;
1232         }
1233
1234         /**
1235          * Update the page record to point to a newly saved revision.
1236          *
1237          * @param DatabaseBase $dbw
1238          * @param Revision $revision For ID number, and text used to set
1239          *   length and redirect status fields
1240          * @param int $lastRevision If given, will not overwrite the page field
1241          *   when different from the currently set value.
1242          *   Giving 0 indicates the new page flag should be set on.
1243          * @param bool $lastRevIsRedirect If given, will optimize adding and
1244          *   removing rows in redirect table.
1245          * @return bool True on success, false on failure
1246          */
1247         public function updateRevisionOn( $dbw, $revision, $lastRevision = null,
1248                 $lastRevIsRedirect = null
1249         ) {
1250                 global $wgContentHandlerUseDB;
1251
1252                 // Assertion to try to catch T92046
1253                 if ( (int)$revision->getId() === 0 ) {
1254                         throw new InvalidArgumentException(
1255                                 __METHOD__ . ': Revision has ID ' . var_export( $revision->getId(), 1 )
1256                         );
1257                 }
1258
1259                 $content = $revision->getContent();
1260                 $len = $content ? $content->getSize() : 0;
1261                 $rt = $content ? $content->getUltimateRedirectTarget() : null;
1262
1263                 $conditions = array( 'page_id' => $this->getId() );
1264
1265                 if ( !is_null( $lastRevision ) ) {
1266                         // An extra check against threads stepping on each other
1267                         $conditions['page_latest'] = $lastRevision;
1268                 }
1269
1270                 $now = wfTimestampNow();
1271                 $row = array( /* SET */
1272                         'page_latest'      => $revision->getId(),
1273                         'page_touched'     => $dbw->timestamp( $now ),
1274                         'page_is_new'      => ( $lastRevision === 0 ) ? 1 : 0,
1275                         'page_is_redirect' => $rt !== null ? 1 : 0,
1276                         'page_len'         => $len,
1277                 );
1278
1279                 if ( $wgContentHandlerUseDB ) {
1280                         $row['page_content_model'] = $revision->getContentModel();
1281                 }
1282
1283                 $dbw->update( 'page',
1284                         $row,
1285                         $conditions,
1286                         __METHOD__ );
1287
1288                 $result = $dbw->affectedRows() > 0;
1289                 if ( $result ) {
1290                         $this->updateRedirectOn( $dbw, $rt, $lastRevIsRedirect );
1291                         $this->setLastEdit( $revision );
1292                         $this->mLatest = $revision->getId();
1293                         $this->mIsRedirect = (bool)$rt;
1294                         // Update the LinkCache.
1295                         LinkCache::singleton()->addGoodLinkObj( $this->getId(), $this->mTitle, $len, $this->mIsRedirect,
1296                                                                                                         $this->mLatest, $revision->getContentModel() );
1297                 }
1298
1299                 return $result;
1300         }
1301
1302         /**
1303          * Add row to the redirect table if this is a redirect, remove otherwise.
1304          *
1305          * @param DatabaseBase $dbw
1306          * @param Title $redirectTitle Title object pointing to the redirect target,
1307          *   or NULL if this is not a redirect
1308          * @param null|bool $lastRevIsRedirect If given, will optimize adding and
1309          *   removing rows in redirect table.
1310          * @return bool True on success, false on failure
1311          * @private
1312          */
1313         public function updateRedirectOn( $dbw, $redirectTitle, $lastRevIsRedirect = null ) {
1314                 // Always update redirects (target link might have changed)
1315                 // Update/Insert if we don't know if the last revision was a redirect or not
1316                 // Delete if changing from redirect to non-redirect
1317                 $isRedirect = !is_null( $redirectTitle );
1318
1319                 if ( !$isRedirect && $lastRevIsRedirect === false ) {
1320                         return true;
1321                 }
1322
1323                 if ( $isRedirect ) {
1324                         $this->insertRedirectEntry( $redirectTitle );
1325                 } else {
1326                         // This is not a redirect, remove row from redirect table
1327                         $where = array( 'rd_from' => $this->getId() );
1328                         $dbw->delete( 'redirect', $where, __METHOD__ );
1329                 }
1330
1331                 if ( $this->getTitle()->getNamespace() == NS_FILE ) {
1332                         RepoGroup::singleton()->getLocalRepo()->invalidateImageRedirect( $this->getTitle() );
1333                 }
1334
1335                 return ( $dbw->affectedRows() != 0 );
1336         }
1337
1338         /**
1339          * If the given revision is newer than the currently set page_latest,
1340          * update the page record. Otherwise, do nothing.
1341          *
1342          * @deprecated since 1.24, use updateRevisionOn instead
1343          *
1344          * @param DatabaseBase $dbw
1345          * @param Revision $revision
1346          * @return bool
1347          */
1348         public function updateIfNewerOn( $dbw, $revision ) {
1349
1350                 $row = $dbw->selectRow(
1351                         array( 'revision', 'page' ),
1352                         array( 'rev_id', 'rev_timestamp', 'page_is_redirect' ),
1353                         array(
1354                                 'page_id' => $this->getId(),
1355                                 'page_latest=rev_id' ),
1356                         __METHOD__ );
1357
1358                 if ( $row ) {
1359                         if ( wfTimestamp( TS_MW, $row->rev_timestamp ) >= $revision->getTimestamp() ) {
1360                                 return false;
1361                         }
1362                         $prev = $row->rev_id;
1363                         $lastRevIsRedirect = (bool)$row->page_is_redirect;
1364                 } else {
1365                         // No or missing previous revision; mark the page as new
1366                         $prev = 0;
1367                         $lastRevIsRedirect = null;
1368                 }
1369
1370                 $ret = $this->updateRevisionOn( $dbw, $revision, $prev, $lastRevIsRedirect );
1371
1372                 return $ret;
1373         }
1374
1375         /**
1376          * Get the content that needs to be saved in order to undo all revisions
1377          * between $undo and $undoafter. Revisions must belong to the same page,
1378          * must exist and must not be deleted
1379          * @param Revision $undo
1380          * @param Revision $undoafter Must be an earlier revision than $undo
1381          * @return mixed String on success, false on failure
1382          * @since 1.21
1383          * Before we had the Content object, this was done in getUndoText
1384          */
1385         public function getUndoContent( Revision $undo, Revision $undoafter = null ) {
1386                 $handler = $undo->getContentHandler();
1387                 return $handler->getUndoContent( $this->getRevision(), $undo, $undoafter );
1388         }
1389
1390         /**
1391          * Get the text that needs to be saved in order to undo all revisions
1392          * between $undo and $undoafter. Revisions must belong to the same page,
1393          * must exist and must not be deleted
1394          * @param Revision $undo
1395          * @param Revision $undoafter Must be an earlier revision than $undo
1396          * @return string|bool String on success, false on failure
1397          * @deprecated since 1.21: use ContentHandler::getUndoContent() instead.
1398          */
1399         public function getUndoText( Revision $undo, Revision $undoafter = null ) {
1400                 ContentHandler::deprecated( __METHOD__, '1.21' );
1401
1402                 $this->loadLastEdit();
1403
1404                 if ( $this->mLastRevision ) {
1405                         if ( is_null( $undoafter ) ) {
1406                                 $undoafter = $undo->getPrevious();
1407                         }
1408
1409                         $handler = $this->getContentHandler();
1410                         $undone = $handler->getUndoContent( $this->mLastRevision, $undo, $undoafter );
1411
1412                         if ( !$undone ) {
1413                                 return false;
1414                         } else {
1415                                 return ContentHandler::getContentText( $undone );
1416                         }
1417                 }
1418
1419                 return false;
1420         }
1421
1422         /**
1423          * @param string|number|null|bool $sectionId Section identifier as a number or string
1424          * (e.g. 0, 1 or 'T-1'), null/false or an empty string for the whole page
1425          * or 'new' for a new section.
1426          * @param string $text New text of the section.
1427          * @param string $sectionTitle New section's subject, only if $section is "new".
1428          * @param string $edittime Revision timestamp or null to use the current revision.
1429          *
1430          * @throws MWException
1431          * @return string New complete article text, or null if error.
1432          *
1433          * @deprecated since 1.21, use replaceSectionAtRev() instead
1434          */
1435         public function replaceSection( $sectionId, $text, $sectionTitle = '',
1436                 $edittime = null
1437         ) {
1438                 ContentHandler::deprecated( __METHOD__, '1.21' );
1439
1440                 //NOTE: keep condition in sync with condition in replaceSectionContent!
1441                 if ( strval( $sectionId ) === '' ) {
1442                         // Whole-page edit; let the whole text through
1443                         return $text;
1444                 }
1445
1446                 if ( !$this->supportsSections() ) {
1447                         throw new MWException( "sections not supported for content model " .
1448                                 $this->getContentHandler()->getModelID() );
1449                 }
1450
1451                 // could even make section title, but that's not required.
1452                 $sectionContent = ContentHandler::makeContent( $text, $this->getTitle() );
1453
1454                 $newContent = $this->replaceSectionContent( $sectionId, $sectionContent, $sectionTitle,
1455                         $edittime );
1456
1457                 return ContentHandler::getContentText( $newContent );
1458         }
1459
1460         /**
1461          * Returns true if this page's content model supports sections.
1462          *
1463          * @return bool
1464          *
1465          * @todo The skin should check this and not offer section functionality if
1466          *   sections are not supported.
1467          * @todo The EditPage should check this and not offer section functionality
1468          *   if sections are not supported.
1469          */
1470         public function supportsSections() {
1471                 return $this->getContentHandler()->supportsSections();
1472         }
1473
1474         /**
1475          * @param string|number|null|bool $sectionId Section identifier as a number or string
1476          * (e.g. 0, 1 or 'T-1'), null/false or an empty string for the whole page
1477          * or 'new' for a new section.
1478          * @param Content $sectionContent New content of the section.
1479          * @param string $sectionTitle New section's subject, only if $section is "new".
1480          * @param string $edittime Revision timestamp or null to use the current revision.
1481          *
1482          * @throws MWException
1483          * @return Content New complete article content, or null if error.
1484          *
1485          * @since 1.21
1486          * @deprecated since 1.24, use replaceSectionAtRev instead
1487          */
1488         public function replaceSectionContent( $sectionId, Content $sectionContent, $sectionTitle = '',
1489                 $edittime = null ) {
1490
1491                 $baseRevId = null;
1492                 if ( $edittime && $sectionId !== 'new' ) {
1493                         $dbr = wfGetDB( DB_SLAVE );
1494                         $rev = Revision::loadFromTimestamp( $dbr, $this->mTitle, $edittime );
1495                         // Try the master if this thread may have just added it.
1496                         // This could be abstracted into a Revision method, but we don't want
1497                         // to encourage loading of revisions by timestamp.
1498                         if ( !$rev
1499                                 && wfGetLB()->getServerCount() > 1
1500                                 && wfGetLB()->hasOrMadeRecentMasterChanges()
1501                         ) {
1502                                 $dbw = wfGetDB( DB_MASTER );
1503                                 $rev = Revision::loadFromTimestamp( $dbw, $this->mTitle, $edittime );
1504                         }
1505                         if ( $rev ) {
1506                                 $baseRevId = $rev->getId();
1507                         }
1508                 }
1509
1510                 return $this->replaceSectionAtRev( $sectionId, $sectionContent, $sectionTitle, $baseRevId );
1511         }
1512
1513         /**
1514          * @param string|number|null|bool $sectionId Section identifier as a number or string
1515          * (e.g. 0, 1 or 'T-1'), null/false or an empty string for the whole page
1516          * or 'new' for a new section.
1517          * @param Content $sectionContent New content of the section.
1518          * @param string $sectionTitle New section's subject, only if $section is "new".
1519          * @param int|null $baseRevId
1520          *
1521          * @throws MWException
1522          * @return Content New complete article content, or null if error.
1523          *
1524          * @since 1.24
1525          */
1526         public function replaceSectionAtRev( $sectionId, Content $sectionContent,
1527                 $sectionTitle = '', $baseRevId = null
1528         ) {
1529
1530                 if ( strval( $sectionId ) === '' ) {
1531                         // Whole-page edit; let the whole text through
1532                         $newContent = $sectionContent;
1533                 } else {
1534                         if ( !$this->supportsSections() ) {
1535                                 throw new MWException( "sections not supported for content model " .
1536                                         $this->getContentHandler()->getModelID() );
1537                         }
1538
1539                         // Bug 30711: always use current version when adding a new section
1540                         if ( is_null( $baseRevId ) || $sectionId === 'new' ) {
1541                                 $oldContent = $this->getContent();
1542                         } else {
1543                                 $rev = Revision::newFromId( $baseRevId );
1544                                 if ( !$rev ) {
1545                                         wfDebug( __METHOD__ . " asked for bogus section (page: " .
1546                                                 $this->getId() . "; section: $sectionId)\n" );
1547                                         return null;
1548                                 }
1549
1550                                 $oldContent = $rev->getContent();
1551                         }
1552
1553                         if ( !$oldContent ) {
1554                                 wfDebug( __METHOD__ . ": no page text\n" );
1555                                 return null;
1556                         }
1557
1558                         $newContent = $oldContent->replaceSection( $sectionId, $sectionContent, $sectionTitle );
1559                 }
1560
1561                 return $newContent;
1562         }
1563
1564         /**
1565          * Check flags and add EDIT_NEW or EDIT_UPDATE to them as needed.
1566          * @param int $flags
1567          * @return int Updated $flags
1568          */
1569         public function checkFlags( $flags ) {
1570                 if ( !( $flags & EDIT_NEW ) && !( $flags & EDIT_UPDATE ) ) {
1571                         if ( $this->exists() ) {
1572                                 $flags |= EDIT_UPDATE;
1573                         } else {
1574                                 $flags |= EDIT_NEW;
1575                         }
1576                 }
1577
1578                 return $flags;
1579         }
1580
1581         /**
1582          * Change an existing article or create a new article. Updates RC and all necessary caches,
1583          * optionally via the deferred update array.
1584          *
1585          * @param string $text New text
1586          * @param string $summary Edit summary
1587          * @param int $flags Bitfield:
1588          *      EDIT_NEW
1589          *          Article is known or assumed to be non-existent, create a new one
1590          *      EDIT_UPDATE
1591          *          Article is known or assumed to be pre-existing, update it
1592          *      EDIT_MINOR
1593          *          Mark this edit minor, if the user is allowed to do so
1594          *      EDIT_SUPPRESS_RC
1595          *          Do not log the change in recentchanges
1596          *      EDIT_FORCE_BOT
1597          *          Mark the edit a "bot" edit regardless of user rights
1598          *      EDIT_DEFER_UPDATES
1599          *          Defer some of the updates until the end of index.php
1600          *      EDIT_AUTOSUMMARY
1601          *          Fill in blank summaries with generated text where possible
1602          *
1603          * If neither EDIT_NEW nor EDIT_UPDATE is specified, the status of the
1604          * article will be detected. If EDIT_UPDATE is specified and the article
1605          * doesn't exist, the function will return an edit-gone-missing error. If
1606          * EDIT_NEW is specified and the article does exist, an edit-already-exists
1607          * error will be returned. These two conditions are also possible with
1608          * auto-detection due to MediaWiki's performance-optimised locking strategy.
1609          *
1610          * @param bool|int $baseRevId The revision ID this edit was based off, if any.
1611          *   This is not the parent revision ID, rather the revision ID for older
1612          *   content used as the source for a rollback, for example.
1613          * @param User $user The user doing the edit
1614          *
1615          * @throws MWException
1616          * @return Status Possible errors:
1617          *   edit-hook-aborted: The ArticleSave hook aborted the edit but didn't
1618          *     set the fatal flag of $status
1619          *   edit-gone-missing: In update mode, but the article didn't exist.
1620          *   edit-conflict: In update mode, the article changed unexpectedly.
1621          *   edit-no-change: Warning that the text was the same as before.
1622          *   edit-already-exists: In creation mode, but the article already exists.
1623          *
1624          * Extensions may define additional errors.
1625          *
1626          * $return->value will contain an associative array with members as follows:
1627          *     new: Boolean indicating if the function attempted to create a new article.
1628          *     revision: The revision object for the inserted revision, or null.
1629          *
1630          * Compatibility note: this function previously returned a boolean value
1631          * indicating success/failure
1632          *
1633          * @deprecated since 1.21: use doEditContent() instead.
1634          */
1635         public function doEdit( $text, $summary, $flags = 0, $baseRevId = false, $user = null ) {
1636                 ContentHandler::deprecated( __METHOD__, '1.21' );
1637
1638                 $content = ContentHandler::makeContent( $text, $this->getTitle() );
1639
1640                 return $this->doEditContent( $content, $summary, $flags, $baseRevId, $user );
1641         }
1642
1643         /**
1644          * Change an existing article or create a new article. Updates RC and all necessary caches,
1645          * optionally via the deferred update array.
1646          *
1647          * @param Content $content New content
1648          * @param string $summary Edit summary
1649          * @param int $flags Bitfield:
1650          *      EDIT_NEW
1651          *          Article is known or assumed to be non-existent, create a new one
1652          *      EDIT_UPDATE
1653          *          Article is known or assumed to be pre-existing, update it
1654          *      EDIT_MINOR
1655          *          Mark this edit minor, if the user is allowed to do so
1656          *      EDIT_SUPPRESS_RC
1657          *          Do not log the change in recentchanges
1658          *      EDIT_FORCE_BOT
1659          *          Mark the edit a "bot" edit regardless of user rights
1660          *      EDIT_DEFER_UPDATES
1661          *          Defer some of the updates until the end of index.php
1662          *      EDIT_AUTOSUMMARY
1663          *          Fill in blank summaries with generated text where possible
1664          *
1665          * If neither EDIT_NEW nor EDIT_UPDATE is specified, the status of the
1666          * article will be detected. If EDIT_UPDATE is specified and the article
1667          * doesn't exist, the function will return an edit-gone-missing error. If
1668          * EDIT_NEW is specified and the article does exist, an edit-already-exists
1669          * error will be returned. These two conditions are also possible with
1670          * auto-detection due to MediaWiki's performance-optimised locking strategy.
1671          *
1672          * @param bool|int $baseRevId The revision ID this edit was based off, if any.
1673          *   This is not the parent revision ID, rather the revision ID for older
1674          *   content used as the source for a rollback, for example.
1675          * @param User $user The user doing the edit
1676          * @param string $serialFormat Format for storing the content in the
1677          *   database.
1678          *
1679          * @throws MWException
1680          * @return Status Possible errors:
1681          *     edit-hook-aborted: The ArticleSave hook aborted the edit but didn't
1682          *       set the fatal flag of $status.
1683          *     edit-gone-missing: In update mode, but the article didn't exist.
1684          *     edit-conflict: In update mode, the article changed unexpectedly.
1685          *     edit-no-change: Warning that the text was the same as before.
1686          *     edit-already-exists: In creation mode, but the article already exists.
1687          *
1688          *  Extensions may define additional errors.
1689          *
1690          *  $return->value will contain an associative array with members as follows:
1691          *     new: Boolean indicating if the function attempted to create a new article.
1692          *     revision: The revision object for the inserted revision, or null.
1693          *
1694          * @since 1.21
1695          * @throws MWException
1696          */
1697         public function doEditContent( Content $content, $summary, $flags = 0, $baseRevId = false,
1698                 User $user = null, $serialFormat = null
1699         ) {
1700                 global $wgUser, $wgUseAutomaticEditSummaries, $wgUseRCPatrol, $wgUseNPPatrol;
1701
1702                 // Low-level sanity check
1703                 if ( $this->mTitle->getText() === '' ) {
1704                         throw new MWException( 'Something is trying to edit an article with an empty title' );
1705                 }
1706
1707                 if ( !$content->getContentHandler()->canBeUsedOn( $this->getTitle() ) ) {
1708                         return Status::newFatal( 'content-not-allowed-here',
1709                                 ContentHandler::getLocalizedName( $content->getModel() ),
1710                                 $this->getTitle()->getPrefixedText() );
1711                 }
1712
1713                 $user = is_null( $user ) ? $wgUser : $user;
1714                 $status = Status::newGood( array() );
1715
1716                 // Load the data from the master database if needed.
1717                 // The caller may already loaded it from the master or even loaded it using
1718                 // SELECT FOR UPDATE, so do not override that using clear().
1719                 $this->loadPageData( 'fromdbmaster' );
1720
1721                 $flags = $this->checkFlags( $flags );
1722
1723                 // handle hook
1724                 $hook_args = array( &$this, &$user, &$content, &$summary,
1725                                                         $flags & EDIT_MINOR, null, null, &$flags, &$status );
1726
1727                 if ( !Hooks::run( 'PageContentSave', $hook_args )
1728                         || !ContentHandler::runLegacyHooks( 'ArticleSave', $hook_args ) ) {
1729
1730                         wfDebug( __METHOD__ . ": ArticleSave or ArticleSaveContent hook aborted save!\n" );
1731
1732                         if ( $status->isOK() ) {
1733                                 $status->fatal( 'edit-hook-aborted' );
1734                         }
1735
1736                         return $status;
1737                 }
1738
1739                 // Silently ignore EDIT_MINOR if not allowed
1740                 $isminor = ( $flags & EDIT_MINOR ) && $user->isAllowed( 'minoredit' );
1741                 $bot = $flags & EDIT_FORCE_BOT;
1742
1743                 $old_content = $this->getContent( Revision::RAW ); // current revision's content
1744
1745                 $oldsize = $old_content ? $old_content->getSize() : 0;
1746                 $oldid = $this->getLatest();
1747                 $oldIsRedirect = $this->isRedirect();
1748                 $oldcountable = $this->isCountable();
1749
1750                 $handler = $content->getContentHandler();
1751
1752                 // Provide autosummaries if one is not provided and autosummaries are enabled.
1753                 if ( $wgUseAutomaticEditSummaries && $flags & EDIT_AUTOSUMMARY && $summary == '' ) {
1754                         if ( !$old_content ) {
1755                                 $old_content = null;
1756                         }
1757                         $summary = $handler->getAutosummary( $old_content, $content, $flags );
1758                 }
1759
1760                 $editInfo = $this->prepareContentForEdit( $content, null, $user, $serialFormat );
1761                 $serialized = $editInfo->pst;
1762
1763                 /**
1764                  * @var Content $content
1765                  */
1766                 $content = $editInfo->pstContent;
1767                 $newsize = $content->getSize();
1768
1769                 $dbw = wfGetDB( DB_MASTER );
1770                 $now = wfTimestampNow();
1771                 $this->mTimestamp = $now;
1772
1773                 if ( $flags & EDIT_UPDATE ) {
1774                         // Update article, but only if changed.
1775                         $status->value['new'] = false;
1776
1777                         if ( !$oldid ) {
1778                                 // Article gone missing
1779                                 wfDebug( __METHOD__ . ": EDIT_UPDATE specified but article doesn't exist\n" );
1780                                 $status->fatal( 'edit-gone-missing' );
1781
1782                                 return $status;
1783                         } elseif ( !$old_content ) {
1784                                 // Sanity check for bug 37225
1785                                 throw new MWException( "Could not find text for current revision {$oldid}." );
1786                         }
1787
1788                         $revision = new Revision( array(
1789                                 'page'       => $this->getId(),
1790                                 'title'      => $this->getTitle(), // for determining the default content model
1791                                 'comment'    => $summary,
1792                                 'minor_edit' => $isminor,
1793                                 'text'       => $serialized,
1794                                 'len'        => $newsize,
1795                                 'parent_id'  => $oldid,
1796                                 'user'       => $user->getId(),
1797                                 'user_text'  => $user->getName(),
1798                                 'timestamp'  => $now,
1799                                 'content_model' => $content->getModel(),
1800                                 'content_format' => $serialFormat,
1801                         ) ); // XXX: pass content object?!
1802
1803                         $changed = !$content->equals( $old_content );
1804
1805                         if ( $changed ) {
1806                                 $dbw->begin( __METHOD__ );
1807
1808                                 $prepStatus = $content->prepareSave( $this, $flags, $oldid, $user );
1809                                 $status->merge( $prepStatus );
1810
1811                                 if ( !$status->isOK() ) {
1812                                         $dbw->rollback( __METHOD__ );
1813
1814                                         return $status;
1815                                 }
1816                                 $revisionId = $revision->insertOn( $dbw );
1817
1818                                 // Update page
1819                                 //
1820                                 // We check for conflicts by comparing $oldid with the current latest revision ID.
1821                                 $ok = $this->updateRevisionOn( $dbw, $revision, $oldid, $oldIsRedirect );
1822
1823                                 if ( !$ok ) {
1824                                         // Belated edit conflict! Run away!!
1825                                         $status->fatal( 'edit-conflict' );
1826
1827                                         $dbw->rollback( __METHOD__ );
1828
1829                                         return $status;
1830                                 }
1831
1832                                 Hooks::run( 'NewRevisionFromEditComplete', array( $this, $revision, $baseRevId, $user ) );
1833
1834                                 // Update recentchanges
1835                                 if ( !( $flags & EDIT_SUPPRESS_RC ) ) {
1836                                         // Mark as patrolled if the user can do so
1837                                         $patrolled = $wgUseRCPatrol && !count(
1838                                                 $this->mTitle->getUserPermissionsErrors( 'autopatrol', $user ) );
1839                                         // Add RC row to the DB
1840                                         RecentChange::notifyEdit(
1841                                                 $now, $this->mTitle, $isminor, $user, $summary,
1842                                                 $oldid, $this->getTimestamp(), $bot, '', $oldsize, $newsize,
1843                                                 $revisionId, $patrolled
1844                                         );
1845                                 }
1846
1847                                 $user->incEditCount();
1848
1849                                 $dbw->commit( __METHOD__ );
1850                         } else {
1851                                 // Bug 32948: revision ID must be set to page {{REVISIONID}} and
1852                                 // related variables correctly
1853                                 $revision->setId( $this->getLatest() );
1854                         }
1855
1856                         // Update links tables, site stats, etc.
1857                         $this->doEditUpdates(
1858                                 $revision,
1859                                 $user,
1860                                 array(
1861                                         'changed' => $changed,
1862                                         'oldcountable' => $oldcountable
1863                                 )
1864                         );
1865
1866                         if ( !$changed ) {
1867                                 $status->warning( 'edit-no-change' );
1868                                 $revision = null;
1869                                 // Update page_touched, this is usually implicit in the page update
1870                                 // Other cache updates are done in onArticleEdit()
1871                                 $this->mTitle->invalidateCache();
1872                         }
1873                 } else {
1874                         // Create new article
1875                         $status->value['new'] = true;
1876
1877                         $dbw->begin( __METHOD__ );
1878
1879                         $prepStatus = $content->prepareSave( $this, $flags, $oldid, $user );
1880                         $status->merge( $prepStatus );
1881
1882                         if ( !$status->isOK() ) {
1883                                 $dbw->rollback( __METHOD__ );
1884
1885                                 return $status;
1886                         }
1887
1888                         $status->merge( $prepStatus );
1889
1890                         // Add the page record; stake our claim on this title!
1891                         // This will return false if the article already exists
1892                         $newid = $this->insertOn( $dbw );
1893
1894                         if ( $newid === false ) {
1895                                 $dbw->rollback( __METHOD__ );
1896                                 $status->fatal( 'edit-already-exists' );
1897
1898                                 return $status;
1899                         }
1900
1901                         // Save the revision text...
1902                         $revision = new Revision( array(
1903                                 'page'       => $newid,
1904                                 'title'      => $this->getTitle(), // for determining the default content model
1905                                 'comment'    => $summary,
1906                                 'minor_edit' => $isminor,
1907                                 'text'       => $serialized,
1908                                 'len'        => $newsize,
1909                                 'user'       => $user->getId(),
1910                                 'user_text'  => $user->getName(),
1911                                 'timestamp'  => $now,
1912                                 'content_model' => $content->getModel(),
1913                                 'content_format' => $serialFormat,
1914                         ) );
1915                         $revisionId = $revision->insertOn( $dbw );
1916
1917                         // Bug 37225: use accessor to get the text as Revision may trim it
1918                         $content = $revision->getContent(); // sanity; get normalized version
1919
1920                         if ( $content ) {
1921                                 $newsize = $content->getSize();
1922                         }
1923
1924                         // Update the page record with revision data
1925                         $this->updateRevisionOn( $dbw, $revision, 0 );
1926
1927                         Hooks::run( 'NewRevisionFromEditComplete', array( $this, $revision, false, $user ) );
1928
1929                         // Update recentchanges
1930                         if ( !( $flags & EDIT_SUPPRESS_RC ) ) {
1931                                 // Mark as patrolled if the user can do so
1932                                 $patrolled = ( $wgUseRCPatrol || $wgUseNPPatrol ) && !count(
1933                                         $this->mTitle->getUserPermissionsErrors( 'autopatrol', $user ) );
1934                                 // Add RC row to the DB
1935                                 RecentChange::notifyNew(
1936                                         $now, $this->mTitle, $isminor, $user, $summary, $bot,
1937                                         '', $newsize, $revisionId, $patrolled
1938                                 );
1939                         }
1940
1941                         $user->incEditCount();
1942
1943                         $dbw->commit( __METHOD__ );
1944
1945                         // Update links, etc.
1946                         $this->doEditUpdates( $revision, $user, array( 'created' => true ) );
1947
1948                         $hook_args = array( &$this, &$user, $content, $summary,
1949                                                                 $flags & EDIT_MINOR, null, null, &$flags, $revision );
1950
1951                         ContentHandler::runLegacyHooks( 'ArticleInsertComplete', $hook_args );
1952                         Hooks::run( 'PageContentInsertComplete', $hook_args );
1953                 }
1954
1955                 // Do updates right now unless deferral was requested
1956                 if ( !( $flags & EDIT_DEFER_UPDATES ) ) {
1957                         DeferredUpdates::doUpdates();
1958                 }
1959
1960                 // Return the new revision (or null) to the caller
1961                 $status->value['revision'] = $revision;
1962
1963                 $hook_args = array( &$this, &$user, $content, $summary,
1964                                                         $flags & EDIT_MINOR, null, null, &$flags, $revision, &$status, $baseRevId );
1965
1966                 ContentHandler::runLegacyHooks( 'ArticleSaveComplete', $hook_args );
1967                 Hooks::run( 'PageContentSaveComplete', $hook_args );
1968
1969                 // Promote user to any groups they meet the criteria for
1970                 $dbw->onTransactionIdle( function () use ( $user ) {
1971                         $user->addAutopromoteOnceGroups( 'onEdit' );
1972                         $user->addAutopromoteOnceGroups( 'onView' ); // b/c
1973                 } );
1974
1975                 return $status;
1976         }
1977
1978         /**
1979          * Get parser options suitable for rendering the primary article wikitext
1980          *
1981          * @see ContentHandler::makeParserOptions
1982          *
1983          * @param IContextSource|User|string $context One of the following:
1984          *        - IContextSource: Use the User and the Language of the provided
1985          *          context
1986          *        - User: Use the provided User object and $wgLang for the language,
1987          *          so use an IContextSource object if possible.
1988          *        - 'canonical': Canonical options (anonymous user with default
1989          *          preferences and content language).
1990          * @return ParserOptions
1991          */
1992         public function makeParserOptions( $context ) {
1993                 $options = $this->getContentHandler()->makeParserOptions( $context );
1994
1995                 if ( $this->getTitle()->isConversionTable() ) {
1996                         // @todo ConversionTable should become a separate content model, so
1997                         // we don't need special cases like this one.
1998                         $options->disableContentConversion();
1999                 }
2000
2001                 return $options;
2002         }
2003
2004         /**
2005          * Prepare text which is about to be saved.
2006          * Returns a stdClass with source, pst and output members
2007          *
2008          * @deprecated since 1.21: use prepareContentForEdit instead.
2009          * @return object
2010          */
2011         public function prepareTextForEdit( $text, $revid = null, User $user = null ) {
2012                 ContentHandler::deprecated( __METHOD__, '1.21' );
2013                 $content = ContentHandler::makeContent( $text, $this->getTitle() );
2014                 return $this->prepareContentForEdit( $content, $revid, $user );
2015         }
2016
2017         /**
2018          * Prepare content which is about to be saved.
2019          * Returns a stdClass with source, pst and output members
2020          *
2021          * @param Content $content
2022          * @param Revision|int|null $revision Revision object. For backwards compatibility, a
2023          *        revision ID is also accepted, but this is deprecated.
2024          * @param User|null $user
2025          * @param string|null $serialFormat
2026          * @param bool $useCache Check shared prepared edit cache
2027          *
2028          * @return object
2029          *
2030          * @since 1.21
2031          */
2032         public function prepareContentForEdit(
2033                 Content $content, $revision = null, User $user = null, $serialFormat = null, $useCache = true
2034         ) {
2035                 global $wgContLang, $wgUser, $wgAjaxEditStash;
2036
2037                 if ( is_object( $revision ) ) {
2038                         $revid = $revision->getId();
2039                 } else {
2040                         $revid = $revision;
2041                         // This code path is deprecated, and nothing is known to
2042                         // use it, so performance here shouldn't be a worry.
2043                         if ( $revid !== null ) {
2044                                 $revision = Revision::newFromId( $revid, Revision::READ_LATEST );
2045                         } else {
2046                                 $revision = null;
2047                         }
2048                 }
2049
2050                 $user = is_null( $user ) ? $wgUser : $user;
2051                 //XXX: check $user->getId() here???
2052
2053                 // Use a sane default for $serialFormat, see bug 57026
2054                 if ( $serialFormat === null ) {
2055                         $serialFormat = $content->getContentHandler()->getDefaultFormat();
2056                 }
2057
2058                 if ( $this->mPreparedEdit
2059                         && $this->mPreparedEdit->newContent
2060                         && $this->mPreparedEdit->newContent->equals( $content )
2061                         && $this->mPreparedEdit->revid == $revid
2062                         && $this->mPreparedEdit->format == $serialFormat
2063                         // XXX: also check $user here?
2064                 ) {
2065                         // Already prepared
2066                         return $this->mPreparedEdit;
2067                 }
2068
2069                 // The edit may have already been prepared via api.php?action=stashedit
2070                 $cachedEdit = $useCache && $wgAjaxEditStash && !$user->isAllowed( 'bot' )
2071                         ? ApiStashEdit::checkCache( $this->getTitle(), $content, $user )
2072                         : false;
2073
2074                 $popts = ParserOptions::newFromUserAndLang( $user, $wgContLang );
2075                 Hooks::run( 'ArticlePrepareTextForEdit', array( $this, $popts ) );
2076
2077                 $edit = (object)array();
2078                 if ( $cachedEdit ) {
2079                         $edit->timestamp = $cachedEdit->timestamp;
2080                 } else {
2081                         $edit->timestamp = wfTimestampNow();
2082                 }
2083                 // @note: $cachedEdit is not used if the rev ID was referenced in the text
2084                 $edit->revid = $revid;
2085
2086                 if ( $cachedEdit ) {
2087                         $edit->pstContent = $cachedEdit->pstContent;
2088                 } else {
2089                         $edit->pstContent = $content
2090                                 ? $content->preSaveTransform( $this->mTitle, $user, $popts )
2091                                 : null;
2092                 }
2093
2094                 $edit->format = $serialFormat;
2095                 $edit->popts = $this->makeParserOptions( 'canonical' );
2096                 if ( $cachedEdit ) {
2097                         $edit->output = $cachedEdit->output;
2098                 } else {
2099                         if ( $revision ) {
2100                                 // We get here if vary-revision is set. This means that this page references
2101                                 // itself (such as via self-transclusion). In this case, we need to make sure
2102                                 // that any such self-references refer to the newly-saved revision, and not
2103                                 // to the previous one, which could otherwise happen due to slave lag.
2104                                 $oldCallback = $edit->popts->setCurrentRevisionCallback(
2105                                         function ( $title, $parser = false ) use ( $revision, &$oldCallback ) {
2106                                                 if ( $title->equals( $revision->getTitle() ) ) {
2107                                                         return $revision;
2108                                                 } else {
2109                                                         return call_user_func(
2110                                                                 $oldCallback,
2111                                                                 $title,
2112                                                                 $parser
2113                                                         );
2114                                                 }
2115                                         }
2116                                 );
2117                         }
2118                         $edit->output = $edit->pstContent
2119                                 ? $edit->pstContent->getParserOutput( $this->mTitle, $revid, $edit->popts )
2120                                 : null;
2121                 }
2122
2123                 $edit->newContent = $content;
2124                 $edit->oldContent = $this->getContent( Revision::RAW );
2125
2126                 // NOTE: B/C for hooks! don't use these fields!
2127                 $edit->newText = $edit->newContent ? ContentHandler::getContentText( $edit->newContent ) : '';
2128                 $edit->oldText = $edit->oldContent ? ContentHandler::getContentText( $edit->oldContent ) : '';
2129                 $edit->pst = $edit->pstContent ? $edit->pstContent->serialize( $serialFormat ) : '';
2130
2131                 $this->mPreparedEdit = $edit;
2132                 return $edit;
2133         }
2134
2135         /**
2136          * Do standard deferred updates after page edit.
2137          * Update links tables, site stats, search index and message cache.
2138          * Purges pages that include this page if the text was changed here.
2139          * Every 100th edit, prune the recent changes table.
2140          *
2141          * @param Revision $revision
2142          * @param User $user User object that did the revision
2143          * @param array $options Array of options, following indexes are used:
2144          * - changed: boolean, whether the revision changed the content (default true)
2145          * - created: boolean, whether the revision created the page (default false)
2146          * - moved: boolean, whether the page was moved (default false)
2147          * - oldcountable: boolean, null, or string 'no-change' (default null):
2148          *   - boolean: whether the page was counted as an article before that
2149          *     revision, only used in changed is true and created is false
2150          *   - null: if created is false, don't update the article count; if created
2151          *     is true, do update the article count
2152          *   - 'no-change': don't update the article count, ever
2153          */
2154         public function doEditUpdates( Revision $revision, User $user, array $options = array() ) {
2155                 global $wgEnableParserCache;
2156
2157                 $options += array(
2158                         'changed' => true,
2159                         'created' => false,
2160                         'moved' => false,
2161                         'oldcountable' => null
2162                 );
2163                 $content = $revision->getContent();
2164
2165                 // Parse the text
2166                 // Be careful not to do pre-save transform twice: $text is usually
2167                 // already pre-save transformed once.
2168                 if ( !$this->mPreparedEdit || $this->mPreparedEdit->output->getFlag( 'vary-revision' ) ) {
2169                         wfDebug( __METHOD__ . ": No prepared edit or vary-revision is set...\n" );
2170                         $editInfo = $this->prepareContentForEdit( $content, $revision, $user );
2171                 } else {
2172                         wfDebug( __METHOD__ . ": No vary-revision, using prepared edit...\n" );
2173                         $editInfo = $this->mPreparedEdit;
2174                 }
2175
2176                 // Save it to the parser cache
2177                 if ( $wgEnableParserCache ) {
2178                         $parserCache = ParserCache::singleton();
2179                         $parserCache->save(
2180                                 $editInfo->output, $this, $editInfo->popts, $editInfo->timestamp, $editInfo->revid
2181                         );
2182                 }
2183
2184                 // Update the links tables and other secondary data
2185                 if ( $content ) {
2186                         $recursive = $options['changed']; // bug 50785
2187                         $updates = $content->getSecondaryDataUpdates(
2188                                 $this->getTitle(), null, $recursive, $editInfo->output );
2189                         foreach ( $updates as $update ) {
2190                                 DeferredUpdates::addUpdate( $update );
2191                         }
2192                 }
2193
2194                 Hooks::run( 'ArticleEditUpdates', array( &$this, &$editInfo, $options['changed'] ) );
2195
2196                 if ( Hooks::run( 'ArticleEditUpdatesDeleteFromRecentchanges', array( &$this ) ) ) {
2197                         // Flush old entries from the `recentchanges` table
2198                         if ( mt_rand( 0, 9 ) == 0 ) {
2199                                 JobQueueGroup::singleton()->lazyPush( RecentChangesUpdateJob::newPurgeJob() );
2200                         }
2201                 }
2202
2203                 if ( !$this->exists() ) {
2204                         return;
2205                 }
2206
2207                 $id = $this->getId();
2208                 $title = $this->mTitle->getPrefixedDBkey();
2209                 $shortTitle = $this->mTitle->getDBkey();
2210
2211                 if ( $options['oldcountable'] === 'no-change' ||
2212                         ( !$options['changed'] && !$options['moved'] )
2213                 ) {
2214                         $good = 0;
2215                 } elseif ( $options['created'] ) {
2216                         $good = (int)$this->isCountable( $editInfo );
2217                 } elseif ( $options['oldcountable'] !== null ) {
2218                         $good = (int)$this->isCountable( $editInfo ) - (int)$options['oldcountable'];
2219                 } else {
2220                         $good = 0;
2221                 }
2222                 $edits = $options['changed'] ? 1 : 0;
2223                 $total = $options['created'] ? 1 : 0;
2224
2225                 DeferredUpdates::addUpdate( new SiteStatsUpdate( 0, $edits, $good, $total ) );
2226                 DeferredUpdates::addUpdate( new SearchUpdate( $id, $title, $content ) );
2227
2228                 // If this is another user's talk page, update newtalk.
2229                 // Don't do this if $options['changed'] = false (null-edits) nor if
2230                 // it's a minor edit and the user doesn't want notifications for those.
2231                 if ( $options['changed']
2232                         && $this->mTitle->getNamespace() == NS_USER_TALK
2233                         && $shortTitle != $user->getTitleKey()
2234                         && !( $revision->isMinor() && $user->isAllowed( 'nominornewtalk' ) )
2235                 ) {
2236                         $recipient = User::newFromName( $shortTitle, false );
2237                         if ( !$recipient ) {
2238                                 wfDebug( __METHOD__ . ": invalid username\n" );
2239                         } else {
2240                                 // Allow extensions to prevent user notification when a new message is added to their talk page
2241                                 if ( Hooks::run( 'ArticleEditUpdateNewTalk', array( &$this, $recipient ) ) ) {
2242                                         if ( User::isIP( $shortTitle ) ) {
2243                                                 // An anonymous user
2244                                                 $recipient->setNewtalk( true, $revision );
2245                                         } elseif ( $recipient->isLoggedIn() ) {
2246                                                 $recipient->setNewtalk( true, $revision );
2247                                         } else {
2248                                                 wfDebug( __METHOD__ . ": don't need to notify a nonexistent user\n" );
2249                                         }
2250                                 }
2251                         }
2252                 }
2253
2254                 if ( $this->mTitle->getNamespace() == NS_MEDIAWIKI ) {
2255                         // XXX: could skip pseudo-messages like js/css here, based on content model.
2256                         $msgtext = $content ? $content->getWikitextForTransclusion() : null;
2257                         if ( $msgtext === false || $msgtext === null ) {
2258                                 $msgtext = '';
2259                         }
2260
2261                         MessageCache::singleton()->replace( $shortTitle, $msgtext );
2262                 }
2263
2264                 if ( $options['created'] ) {
2265                         self::onArticleCreate( $this->mTitle );
2266                 } elseif ( $options['changed'] ) { // bug 50785
2267                         self::onArticleEdit( $this->mTitle );
2268                 }
2269         }
2270
2271         /**
2272          * Edit an article without doing all that other stuff
2273          * The article must already exist; link tables etc
2274          * are not updated, caches are not flushed.
2275          *
2276          * @param string $text Text submitted
2277          * @param User $user The relevant user
2278          * @param string $comment Comment submitted
2279          * @param bool $minor Whereas it's a minor modification
2280          *
2281          * @deprecated since 1.21, use doEditContent() instead.
2282          */
2283         public function doQuickEdit( $text, User $user, $comment = '', $minor = 0 ) {
2284                 ContentHandler::deprecated( __METHOD__, "1.21" );
2285
2286                 $content = ContentHandler::makeContent( $text, $this->getTitle() );
2287                 $this->doQuickEditContent( $content, $user, $comment, $minor );
2288         }
2289
2290         /**
2291          * Edit an article without doing all that other stuff
2292          * The article must already exist; link tables etc
2293          * are not updated, caches are not flushed.
2294          *
2295          * @param Content $content Content submitted
2296          * @param User $user The relevant user
2297          * @param string $comment Comment submitted
2298          * @param bool $minor Whereas it's a minor modification
2299          * @param string $serialFormat Format for storing the content in the database
2300          */
2301         public function doQuickEditContent( Content $content, User $user, $comment = '', $minor = false,
2302                 $serialFormat = null
2303         ) {
2304
2305                 $serialized = $content->serialize( $serialFormat );
2306
2307                 $dbw = wfGetDB( DB_MASTER );
2308                 $revision = new Revision( array(
2309                         'title'      => $this->getTitle(), // for determining the default content model
2310                         'page'       => $this->getId(),
2311                         'user_text'  => $user->getName(),
2312                         'user'       => $user->getId(),
2313                         'text'       => $serialized,
2314                         'length'     => $content->getSize(),
2315                         'comment'    => $comment,
2316                         'minor_edit' => $minor ? 1 : 0,
2317                 ) ); // XXX: set the content object?
2318                 $revision->insertOn( $dbw );
2319                 $this->updateRevisionOn( $dbw, $revision );
2320
2321                 Hooks::run( 'NewRevisionFromEditComplete', array( $this, $revision, false, $user ) );
2322
2323         }
2324
2325         /**
2326          * Update the article's restriction field, and leave a log entry.
2327          * This works for protection both existing and non-existing pages.
2328          *
2329          * @param array $limit Set of restriction keys
2330          * @param array $expiry Per restriction type expiration
2331          * @param int &$cascade Set to false if cascading protection isn't allowed.
2332          * @param string $reason
2333          * @param User $user The user updating the restrictions
2334          * @return Status
2335          */
2336         public function doUpdateRestrictions( array $limit, array $expiry,
2337                 &$cascade, $reason, User $user
2338         ) {
2339                 global $wgCascadingRestrictionLevels, $wgContLang;
2340
2341                 if ( wfReadOnly() ) {
2342                         return Status::newFatal( 'readonlytext', wfReadOnlyReason() );
2343                 }
2344
2345                 $this->loadPageData( 'fromdbmaster' );
2346                 $restrictionTypes = $this->mTitle->getRestrictionTypes();
2347                 $id = $this->getId();
2348
2349                 if ( !$cascade ) {
2350                         $cascade = false;
2351                 }
2352
2353                 // Take this opportunity to purge out expired restrictions
2354                 Title::purgeExpiredRestrictions();
2355
2356                 // @todo FIXME: Same limitations as described in ProtectionForm.php (line 37);
2357                 // we expect a single selection, but the schema allows otherwise.
2358                 $isProtected = false;
2359                 $protect = false;
2360                 $changed = false;
2361
2362                 $dbw = wfGetDB( DB_MASTER );
2363
2364                 foreach ( $restrictionTypes as $action ) {
2365                         if ( !isset( $expiry[$action] ) || $expiry[$action] === $dbw->getInfinity() ) {
2366                                 $expiry[$action] = 'infinity';
2367                         }
2368                         if ( !isset( $limit[$action] ) ) {
2369                                 $limit[$action] = '';
2370                         } elseif ( $limit[$action] != '' ) {
2371                                 $protect = true;
2372                         }
2373
2374                         // Get current restrictions on $action
2375                         $current = implode( '', $this->mTitle->getRestrictions( $action ) );
2376                         if ( $current != '' ) {
2377                                 $isProtected = true;
2378                         }
2379
2380                         if ( $limit[$action] != $current ) {
2381                                 $changed = true;
2382                         } elseif ( $limit[$action] != '' ) {
2383                                 // Only check expiry change if the action is actually being
2384                                 // protected, since expiry does nothing on an not-protected
2385                                 // action.
2386                                 if ( $this->mTitle->getRestrictionExpiry( $action ) != $expiry[$action] ) {
2387                                         $changed = true;
2388                                 }
2389                         }
2390                 }
2391
2392                 if ( !$changed && $protect && $this->mTitle->areRestrictionsCascading() != $cascade ) {
2393                         $changed = true;
2394                 }
2395
2396                 // If nothing has changed, do nothing
2397                 if ( !$changed ) {
2398                         return Status::newGood();
2399                 }
2400
2401                 if ( !$protect ) { // No protection at all means unprotection
2402                         $revCommentMsg = 'unprotectedarticle';
2403                         $logAction = 'unprotect';
2404                 } elseif ( $isProtected ) {
2405                         $revCommentMsg = 'modifiedarticleprotection';
2406                         $logAction = 'modify';
2407                 } else {
2408                         $revCommentMsg = 'protectedarticle';
2409                         $logAction = 'protect';
2410                 }
2411
2412                 // Truncate for whole multibyte characters
2413                 $reason = $wgContLang->truncate( $reason, 255 );
2414
2415                 $logRelationsValues = array();
2416                 $logRelationsField = null;
2417
2418                 if ( $id ) { // Protection of existing page
2419                         if ( !Hooks::run( 'ArticleProtect', array( &$this, &$user, $limit, $reason ) ) ) {
2420                                 return Status::newGood();
2421                         }
2422
2423                         // Only certain restrictions can cascade...
2424                         $editrestriction = isset( $limit['edit'] )
2425                                 ? array( $limit['edit'] )
2426                                 : $this->mTitle->getRestrictions( 'edit' );
2427                         foreach ( array_keys( $editrestriction, 'sysop' ) as $key ) {
2428                                 $editrestriction[$key] = 'editprotected'; // backwards compatibility
2429                         }
2430                         foreach ( array_keys( $editrestriction, 'autoconfirmed' ) as $key ) {
2431                                 $editrestriction[$key] = 'editsemiprotected'; // backwards compatibility
2432                         }
2433
2434                         $cascadingRestrictionLevels = $wgCascadingRestrictionLevels;
2435                         foreach ( array_keys( $cascadingRestrictionLevels, 'sysop' ) as $key ) {
2436                                 $cascadingRestrictionLevels[$key] = 'editprotected'; // backwards compatibility
2437                         }
2438                         foreach ( array_keys( $cascadingRestrictionLevels, 'autoconfirmed' ) as $key ) {
2439                                 $cascadingRestrictionLevels[$key] = 'editsemiprotected'; // backwards compatibility
2440                         }
2441
2442                         // The schema allows multiple restrictions
2443                         if ( !array_intersect( $editrestriction, $cascadingRestrictionLevels ) ) {
2444                                 $cascade = false;
2445                         }
2446
2447                         // insert null revision to identify the page protection change as edit summary
2448                         $latest = $this->getLatest();
2449                         $nullRevision = $this->insertProtectNullRevision(
2450                                 $revCommentMsg,
2451                                 $limit,
2452                                 $expiry,
2453                                 $cascade,
2454                                 $reason,
2455                                 $user
2456                         );
2457
2458                         if ( $nullRevision === null ) {
2459                                 return Status::newFatal( 'no-null-revision', $this->mTitle->getPrefixedText() );
2460                         }
2461
2462                         $logRelationsField = 'pr_id';
2463
2464                         // Update restrictions table
2465                         foreach ( $limit as $action => $restrictions ) {
2466                                 $dbw->delete(
2467                                         'page_restrictions',
2468                                         array(
2469                                                 'pr_page' => $id,
2470                                                 'pr_type' => $action
2471                                         ),
2472                                         __METHOD__
2473                                 );
2474                                 if ( $restrictions != '' ) {
2475                                         $dbw->insert(
2476                                                 'page_restrictions',
2477                                                 array(
2478                                                         'pr_id' => $dbw->nextSequenceValue( 'page_restrictions_pr_id_seq' ),
2479                                                         'pr_page' => $id,
2480                                                         'pr_type' => $action,
2481                                                         'pr_level' => $restrictions,
2482                                                         'pr_cascade' => ( $cascade && $action == 'edit' ) ? 1 : 0,
2483                                                         'pr_expiry' => $dbw->encodeExpiry( $expiry[$action] )
2484                                                 ),
2485                                                 __METHOD__
2486                                         );
2487                                         $logRelationsValues[] = $dbw->insertId();
2488                                 }
2489                         }
2490
2491                         // Clear out legacy restriction fields
2492                         $dbw->update(
2493                                 'page',
2494                                 array( 'page_restrictions' => '' ),
2495                                 array( 'page_id' => $id ),
2496                                 __METHOD__
2497                         );
2498
2499                         Hooks::run( 'NewRevisionFromEditComplete', array( $this, $nullRevision, $latest, $user ) );
2500                         Hooks::run( 'ArticleProtectComplete', array( &$this, &$user, $limit, $reason ) );
2501                 } else { // Protection of non-existing page (also known as "title protection")
2502                         // Cascade protection is meaningless in this case
2503                         $cascade = false;
2504
2505                         if ( $limit['create'] != '' ) {
2506                                 $dbw->replace( 'protected_titles',
2507                                         array( array( 'pt_namespace', 'pt_title' ) ),
2508                                         array(
2509                                                 'pt_namespace' => $this->mTitle->getNamespace(),
2510                                                 'pt_title' => $this->mTitle->getDBkey(),
2511                                                 'pt_create_perm' => $limit['create'],
2512                                                 'pt_timestamp' => $dbw->timestamp(),
2513                                                 'pt_expiry' => $dbw->encodeExpiry( $expiry['create'] ),
2514                                                 'pt_user' => $user->getId(),
2515                                                 'pt_reason' => $reason,
2516                                         ), __METHOD__
2517                                 );
2518                         } else {
2519                                 $dbw->delete( 'protected_titles',
2520                                         array(
2521                                                 'pt_namespace' => $this->mTitle->getNamespace(),
2522                                                 'pt_title' => $this->mTitle->getDBkey()
2523                                         ), __METHOD__
2524                                 );
2525                         }
2526                 }
2527
2528                 $this->mTitle->flushRestrictions();
2529                 InfoAction::invalidateCache( $this->mTitle );
2530
2531                 if ( $logAction == 'unprotect' ) {
2532                         $params = array();
2533                 } else {
2534                         $protectDescriptionLog = $this->protectDescriptionLog( $limit, $expiry );
2535                         $params = array( $protectDescriptionLog, $cascade ? 'cascade' : '' );
2536                 }
2537
2538                 // Update the protection log
2539                 $log = new LogPage( 'protect' );
2540                 $logId = $log->addEntry( $logAction, $this->mTitle, $reason, $params, $user );
2541                 if ( $logRelationsField !== null && count( $logRelationsValues ) ) {
2542                         $log->addRelations( $logRelationsField, $logRelationsValues, $logId );
2543                 }
2544
2545                 return Status::newGood();
2546         }
2547
2548         /**
2549          * Insert a new null revision for this page.
2550          *
2551          * @param string $revCommentMsg Comment message key for the revision
2552          * @param array $limit Set of restriction keys
2553          * @param array $expiry Per restriction type expiration
2554          * @param int $cascade Set to false if cascading protection isn't allowed.
2555          * @param string $reason
2556          * @param User|null $user
2557          * @return Revision|null Null on error
2558          */
2559         public function insertProtectNullRevision( $revCommentMsg, array $limit,
2560                 array $expiry, $cascade, $reason, $user = null
2561         ) {
2562                 global $wgContLang;
2563                 $dbw = wfGetDB( DB_MASTER );
2564
2565                 // Prepare a null revision to be added to the history
2566                 $editComment = $wgContLang->ucfirst(
2567                         wfMessage(
2568                                 $revCommentMsg,
2569                                 $this->mTitle->getPrefixedText()
2570                         )->inContentLanguage()->text()
2571                 );
2572                 if ( $reason ) {
2573                         $editComment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
2574                 }
2575                 $protectDescription = $this->protectDescription( $limit, $expiry );
2576                 if ( $protectDescription ) {
2577                         $editComment .= wfMessage( 'word-separator' )->inContentLanguage()->text();
2578                         $editComment .= wfMessage( 'parentheses' )->params( $protectDescription )
2579                                 ->inContentLanguage()->text();
2580                 }
2581                 if ( $cascade ) {
2582                         $editComment .= wfMessage( 'word-separator' )->inContentLanguage()->text();
2583                         $editComment .= wfMessage( 'brackets' )->params(
2584                                 wfMessage( 'protect-summary-cascade' )->inContentLanguage()->text()
2585                         )->inContentLanguage()->text();
2586                 }
2587
2588                 $nullRev = Revision::newNullRevision( $dbw, $this->getId(), $editComment, true, $user );
2589                 if ( $nullRev ) {
2590                         $nullRev->insertOn( $dbw );
2591
2592                         // Update page record and touch page
2593                         $oldLatest = $nullRev->getParentId();
2594                         $this->updateRevisionOn( $dbw, $nullRev, $oldLatest );
2595                 }
2596
2597                 return $nullRev;
2598         }
2599
2600         /**
2601          * @param string $expiry 14-char timestamp or "infinity", or false if the input was invalid
2602          * @return string
2603          */
2604         protected function formatExpiry( $expiry ) {
2605                 global $wgContLang;
2606
2607                 if ( $expiry != 'infinity' ) {
2608                         return wfMessage(
2609                                 'protect-expiring',
2610                                 $wgContLang->timeanddate( $expiry, false, false ),
2611                                 $wgContLang->date( $expiry, false, false ),
2612                                 $wgContLang->time( $expiry, false, false )
2613                         )->inContentLanguage()->text();
2614                 } else {
2615                         return wfMessage( 'protect-expiry-indefinite' )
2616                                 ->inContentLanguage()->text();
2617                 }
2618         }
2619
2620         /**
2621          * Builds the description to serve as comment for the edit.
2622          *
2623          * @param array $limit Set of restriction keys
2624          * @param array $expiry Per restriction type expiration
2625          * @return string
2626          */
2627         public function protectDescription( array $limit, array $expiry ) {
2628                 $protectDescription = '';
2629
2630                 foreach ( array_filter( $limit ) as $action => $restrictions ) {
2631                         # $action is one of $wgRestrictionTypes = array( 'create', 'edit', 'move', 'upload' ).
2632                         # All possible message keys are listed here for easier grepping:
2633                         # * restriction-create
2634                         # * restriction-edit
2635                         # * restriction-move
2636                         # * restriction-upload
2637                         $actionText = wfMessage( 'restriction-' . $action )->inContentLanguage()->text();
2638                         # $restrictions is one of $wgRestrictionLevels = array( '', 'autoconfirmed', 'sysop' ),
2639                         # with '' filtered out. All possible message keys are listed below:
2640                         # * protect-level-autoconfirmed
2641                         # * protect-level-sysop
2642                         $restrictionsText = wfMessage( 'protect-level-' . $restrictions )->inContentLanguage()->text();
2643
2644                         $expiryText = $this->formatExpiry( $expiry[$action] );
2645
2646                         if ( $protectDescription !== '' ) {
2647                                 $protectDescription .= wfMessage( 'word-separator' )->inContentLanguage()->text();
2648                         }
2649                         $protectDescription .= wfMessage( 'protect-summary-desc' )
2650                                 ->params( $actionText, $restrictionsText, $expiryText )
2651                                 ->inContentLanguage()->text();
2652                 }
2653
2654                 return $protectDescription;
2655         }
2656
2657         /**
2658          * Builds the description to serve as comment for the log entry.
2659          *
2660          * Some bots may parse IRC lines, which are generated from log entries which contain plain
2661          * protect description text. Keep them in old format to avoid breaking compatibility.
2662          * TODO: Fix protection log to store structured description and format it on-the-fly.
2663          *
2664          * @param array $limit Set of restriction keys
2665          * @param array $expiry Per restriction type expiration
2666          * @return string
2667          */
2668         public function protectDescriptionLog( array $limit, array $expiry ) {
2669                 global $wgContLang;
2670
2671                 $protectDescriptionLog = '';
2672
2673                 foreach ( array_filter( $limit ) as $action => $restrictions ) {
2674                         $expiryText = $this->formatExpiry( $expiry[$action] );
2675                         $protectDescriptionLog .= $wgContLang->getDirMark() . "[$action=$restrictions] ($expiryText)";
2676                 }
2677
2678                 return trim( $protectDescriptionLog );
2679         }
2680
2681         /**
2682          * Take an array of page restrictions and flatten it to a string
2683          * suitable for insertion into the page_restrictions field.
2684          *
2685          * @param string[] $limit
2686          *
2687          * @throws MWException
2688          * @return string
2689          */
2690         protected static function flattenRestrictions( $limit ) {
2691                 if ( !is_array( $limit ) ) {
2692                         throw new MWException( 'WikiPage::flattenRestrictions given non-array restriction set' );
2693                 }
2694
2695                 $bits = array();
2696                 ksort( $limit );
2697
2698                 foreach ( array_filter( $limit ) as $action => $restrictions ) {
2699                         $bits[] = "$action=$restrictions";
2700                 }
2701
2702                 return implode( ':', $bits );
2703         }
2704
2705         /**
2706          * Same as doDeleteArticleReal(), but returns a simple boolean. This is kept around for
2707          * backwards compatibility, if you care about error reporting you should use
2708          * doDeleteArticleReal() instead.
2709          *
2710          * Deletes the article with database consistency, writes logs, purges caches
2711          *
2712          * @param string $reason Delete reason for deletion log
2713          * @param bool $suppress Suppress all revisions and log the deletion in
2714          *        the suppression log instead of the deletion log
2715          * @param int $id Article ID
2716          * @param bool $commit Defaults to true, triggers transaction end
2717          * @param array &$error Array of errors to append to
2718          * @param User $user The deleting user
2719          * @return bool True if successful
2720          */
2721         public function doDeleteArticle(
2722                 $reason, $suppress = false, $id = 0, $commit = true, &$error = '', User $user = null
2723         ) {
2724                 $status = $this->doDeleteArticleReal( $reason, $suppress, $id, $commit, $error, $user );
2725                 return $status->isGood();
2726         }
2727
2728         /**
2729          * Back-end article deletion
2730          * Deletes the article with database consistency, writes logs, purges caches
2731          *
2732          * @since 1.19
2733          *
2734          * @param string $reason Delete reason for deletion log
2735          * @param bool $suppress Suppress all revisions and log the deletion in
2736          *   the suppression log instead of the deletion log
2737          * @param int $id Article ID
2738          * @param bool $commit Defaults to true, triggers transaction end
2739          * @param array &$error Array of errors to append to
2740          * @param User $user The deleting user
2741          * @return Status Status object; if successful, $status->value is the log_id of the
2742          *   deletion log entry. If the page couldn't be deleted because it wasn't
2743          *   found, $status is a non-fatal 'cannotdelete' error
2744          */
2745         public function doDeleteArticleReal(
2746                 $reason, $suppress = false, $id = 0, $commit = true, &$error = '', User $user = null
2747         ) {
2748                 global $wgUser, $wgContentHandlerUseDB;
2749
2750                 wfDebug( __METHOD__ . "\n" );
2751
2752                 $status = Status::newGood();
2753
2754                 if ( $this->mTitle->getDBkey() === '' ) {
2755                         $status->error( 'cannotdelete', wfEscapeWikiText( $this->getTitle()->getPrefixedText() ) );
2756                         return $status;
2757                 }
2758
2759                 $user = is_null( $user ) ? $wgUser : $user;
2760                 if ( !Hooks::run( 'ArticleDelete', array( &$this, &$user, &$reason, &$error, &$status ) ) ) {
2761                         if ( $status->isOK() ) {
2762                                 // Hook aborted but didn't set a fatal status
2763                                 $status->fatal( 'delete-hook-aborted' );
2764                         }
2765                         return $status;
2766                 }
2767
2768                 $dbw = wfGetDB( DB_MASTER );
2769                 $dbw->begin( __METHOD__ );
2770
2771                 if ( $id == 0 ) {
2772                         // T98706: lock the page from various other updates but avoid using
2773                         // WikiPage::READ_LOCKING as that will carry over the FOR UPDATE to
2774                         // the revisions queries (which also JOIN on user). Only lock the page
2775                         // row and CAS check on page_latest to see if the trx snapshot matches.
2776                         $latest = $this->lock();
2777
2778                         $this->loadPageData( WikiPage::READ_LATEST );
2779                         $id = $this->getID();
2780                         if ( $id == 0 || $this->getLatest() != $latest ) {
2781                                 // Page not there or trx snapshot is stale
2782                                 $dbw->rollback( __METHOD__ );
2783                                 $status->error( 'cannotdelete', wfEscapeWikiText( $this->getTitle()->getPrefixedText() ) );
2784                                 return $status;
2785                         }
2786                 }
2787
2788                 // we need to remember the old content so we can use it to generate all deletion updates.
2789                 $content = $this->getContent( Revision::RAW );
2790
2791                 // Bitfields to further suppress the content
2792                 if ( $suppress ) {
2793                         $bitfield = 0;
2794                         // This should be 15...
2795                         $bitfield |= Revision::DELETED_TEXT;
2796                         $bitfield |= Revision::DELETED_COMMENT;
2797                         $bitfield |= Revision::DELETED_USER;
2798                         $bitfield |= Revision::DELETED_RESTRICTED;
2799                 } else {
2800                         $bitfield = 'rev_deleted';
2801                 }
2802
2803                 // For now, shunt the revision data into the archive table.
2804                 // Text is *not* removed from the text table; bulk storage
2805                 // is left intact to avoid breaking block-compression or
2806                 // immutable storage schemes.
2807                 //
2808                 // For backwards compatibility, note that some older archive
2809                 // table entries will have ar_text and ar_flags fields still.
2810                 //
2811                 // In the future, we may keep revisions and mark them with
2812                 // the rev_deleted field, which is reserved for this purpose.
2813
2814                 $row = array(
2815                         'ar_namespace'  => 'page_namespace',
2816                         'ar_title'      => 'page_title',
2817                         'ar_comment'    => 'rev_comment',
2818                         'ar_user'       => 'rev_user',
2819                         'ar_user_text'  => 'rev_user_text',
2820                         'ar_timestamp'  => 'rev_timestamp',
2821                         'ar_minor_edit' => 'rev_minor_edit',
2822                         'ar_rev_id'     => 'rev_id',
2823                         'ar_parent_id'  => 'rev_parent_id',
2824                         'ar_text_id'    => 'rev_text_id',
2825                         'ar_text'       => '\'\'', // Be explicit to appease
2826                         'ar_flags'      => '\'\'', // MySQL's "strict mode"...
2827                         'ar_len'        => 'rev_len',
2828                         'ar_page_id'    => 'page_id',
2829                         'ar_deleted'    => $bitfield,
2830                         'ar_sha1'       => 'rev_sha1',
2831                 );
2832
2833                 if ( $wgContentHandlerUseDB ) {
2834                         $row['ar_content_model'] = 'rev_content_model';
2835                         $row['ar_content_format'] = 'rev_content_format';
2836                 }
2837
2838                 $dbw->insertSelect( 'archive', array( 'page', 'revision' ),
2839                         $row,
2840                         array(
2841                                 'page_id' => $id,
2842                                 'page_id = rev_page'
2843                         ), __METHOD__
2844                 );
2845
2846                 // Now that it's safely backed up, delete it
2847                 $dbw->delete( 'page', array( 'page_id' => $id ), __METHOD__ );
2848                 $ok = ( $dbw->affectedRows() > 0 ); // $id could be laggy
2849
2850                 if ( !$ok ) {
2851                         $dbw->rollback( __METHOD__ );
2852                         $status->error( 'cannotdelete', wfEscapeWikiText( $this->getTitle()->getPrefixedText() ) );
2853                         return $status;
2854                 }
2855
2856                 if ( !$dbw->cascadingDeletes() ) {
2857                         $dbw->delete( 'revision', array( 'rev_page' => $id ), __METHOD__ );
2858                 }
2859
2860                 // Clone the title, so we have the information we need when we log
2861                 $logTitle = clone $this->mTitle;
2862
2863                 // Log the deletion, if the page was suppressed, log it at Oversight instead
2864                 $logtype = $suppress ? 'suppress' : 'delete';
2865
2866                 $logEntry = new ManualLogEntry( $logtype, 'delete' );
2867                 $logEntry->setPerformer( $user );
2868                 $logEntry->setTarget( $logTitle );
2869                 $logEntry->setComment( $reason );
2870                 $logid = $logEntry->insert();
2871
2872                 $dbw->onTransactionPreCommitOrIdle( function () use ( $dbw, $logEntry, $logid ) {
2873                         // Bug 56776: avoid deadlocks (especially from FileDeleteForm)
2874                         $logEntry->publish( $logid );
2875                 } );
2876
2877                 if ( $commit ) {
2878                         $dbw->commit( __METHOD__ );
2879                 }
2880
2881                 $this->doDeleteUpdates( $id, $content );
2882
2883                 Hooks::run( 'ArticleDeleteComplete', array( &$this, &$user, $reason, $id, $content, $logEntry ) );
2884                 $status->value = $logid;
2885                 return $status;
2886         }
2887
2888         /**
2889          * Lock the page row for this title and return page_latest (or 0)
2890          *
2891          * @return integer
2892          */
2893         protected function lock() {
2894                 return (int)wfGetDB( DB_MASTER )->selectField(
2895                         'page',
2896                         'page_latest',
2897                         array(
2898                                 'page_namespace' => $this->getTitle()->getNamespace(),
2899                                 'page_title' => $this->getTitle()->getDBkey()
2900                         ),
2901                         __METHOD__,
2902                         array( 'FOR UPDATE' )
2903                 );
2904         }
2905
2906         /**
2907          * Do some database updates after deletion
2908          *
2909          * @param int $id The page_id value of the page being deleted
2910          * @param Content $content Optional page content to be used when determining
2911          *   the required updates. This may be needed because $this->getContent()
2912          *   may already return null when the page proper was deleted.
2913          */
2914         public function doDeleteUpdates( $id, Content $content = null ) {
2915                 // update site status
2916                 DeferredUpdates::addUpdate( new SiteStatsUpdate( 0, 1, - (int)$this->isCountable(), -1 ) );
2917
2918                 // remove secondary indexes, etc
2919                 $updates = $this->getDeletionUpdates( $content );
2920                 DataUpdate::runUpdates( $updates );
2921
2922                 // Reparse any pages transcluding this page
2923                 LinksUpdate::queueRecursiveJobsForTable( $this->mTitle, 'templatelinks' );
2924
2925                 // Reparse any pages including this image
2926                 if ( $this->mTitle->getNamespace() == NS_FILE ) {
2927                         LinksUpdate::queueRecursiveJobsForTable( $this->mTitle, 'imagelinks' );
2928                 }
2929
2930                 // Clear caches
2931                 WikiPage::onArticleDelete( $this->mTitle );
2932
2933                 // Reset this object and the Title object
2934                 $this->loadFromRow( false, self::READ_LATEST );
2935
2936                 // Search engine
2937                 DeferredUpdates::addUpdate( new SearchUpdate( $id, $this->mTitle ) );
2938         }
2939
2940         /**
2941          * Roll back the most recent consecutive set of edits to a page
2942          * from the same user; fails if there are no eligible edits to
2943          * roll back to, e.g. user is the sole contributor. This function
2944          * performs permissions checks on $user, then calls commitRollback()
2945          * to do the dirty work
2946          *
2947          * @todo Separate the business/permission stuff out from backend code
2948          *
2949          * @param string $fromP Name of the user whose edits to rollback.
2950          * @param string $summary Custom summary. Set to default summary if empty.
2951          * @param string $token Rollback token.
2952          * @param bool $bot If true, mark all reverted edits as bot.
2953          *
2954          * @param array $resultDetails Array contains result-specific array of additional values
2955          *    'alreadyrolled' : 'current' (rev)
2956          *    success        : 'summary' (str), 'current' (rev), 'target' (rev)
2957          *
2958          * @param User $user The user performing the rollback
2959          * @return array Array of errors, each error formatted as
2960          *   array(messagekey, param1, param2, ...).
2961          * On success, the array is empty.  This array can also be passed to
2962          * OutputPage::showPermissionsErrorPage().
2963          */
2964         public function doRollback(
2965                 $fromP, $summary, $token, $bot, &$resultDetails, User $user
2966         ) {
2967                 $resultDetails = null;
2968
2969                 // Check permissions
2970                 $editErrors = $this->mTitle->getUserPermissionsErrors( 'edit', $user );
2971                 $rollbackErrors = $this->mTitle->getUserPermissionsErrors( 'rollback', $user );
2972                 $errors = array_merge( $editErrors, wfArrayDiff2( $rollbackErrors, $editErrors ) );
2973
2974                 if ( !$user->matchEditToken( $token, array( $this->mTitle->getPrefixedText(), $fromP ) ) ) {
2975                         $errors[] = array( 'sessionfailure' );
2976                 }
2977
2978                 if ( $user->pingLimiter( 'rollback' ) || $user->pingLimiter() ) {
2979                         $errors[] = array( 'actionthrottledtext' );
2980                 }
2981
2982                 // If there were errors, bail out now
2983                 if ( !empty( $errors ) ) {
2984                         return $errors;
2985                 }
2986
2987                 return $this->commitRollback( $fromP, $summary, $bot, $resultDetails, $user );
2988         }
2989
2990         /**
2991          * Backend implementation of doRollback(), please refer there for parameter
2992          * and return value documentation
2993          *
2994          * NOTE: This function does NOT check ANY permissions, it just commits the
2995          * rollback to the DB. Therefore, you should only call this function direct-
2996          * ly if you want to use custom permissions checks. If you don't, use
2997          * doRollback() instead.
2998          * @param string $fromP Name of the user whose edits to rollback.
2999          * @param string $summary Custom summary. Set to default summary if empty.
3000          * @param bool $bot If true, mark all reverted edits as bot.
3001          *
3002          * @param array $resultDetails Contains result-specific array of additional values
3003          * @param User $guser The user performing the rollback
3004          * @return array
3005          */
3006         public function commitRollback( $fromP, $summary, $bot, &$resultDetails, User $guser ) {
3007                 global $wgUseRCPatrol, $wgContLang;
3008
3009                 $dbw = wfGetDB( DB_MASTER );
3010
3011                 if ( wfReadOnly() ) {
3012                         return array( array( 'readonlytext' ) );
3013                 }
3014
3015                 // Get the last editor
3016                 $current = $this->getRevision();
3017                 if ( is_null( $current ) ) {
3018                         // Something wrong... no page?
3019                         return array( array( 'notanarticle' ) );
3020                 }
3021
3022                 $from = str_replace( '_', ' ', $fromP );
3023                 // User name given should match up with the top revision.
3024                 // If the user was deleted then $from should be empty.
3025                 if ( $from != $current->getUserText() ) {
3026                         $resultDetails = array( 'current' => $current );
3027                         return array( array( 'alreadyrolled',
3028                                 htmlspecialchars( $this->mTitle->getPrefixedText() ),
3029                                 htmlspecialchars( $fromP ),
3030                                 htmlspecialchars( $current->getUserText() )
3031                         ) );
3032                 }
3033
3034                 // Get the last edit not by this guy...
3035                 // Note: these may not be public values
3036                 $user = intval( $current->getUser( Revision::RAW ) );
3037                 $user_text = $dbw->addQuotes( $current->getUserText( Revision::RAW ) );
3038                 $s = $dbw->selectRow( 'revision',
3039                         array( 'rev_id', 'rev_timestamp', 'rev_deleted' ),
3040                         array( 'rev_page' => $current->getPage(),
3041                                 "rev_user != {$user} OR rev_user_text != {$user_text}"
3042                         ), __METHOD__,
3043                         array( 'USE INDEX' => 'page_timestamp',
3044                                 'ORDER BY' => 'rev_timestamp DESC' )
3045                         );
3046                 if ( $s === false ) {
3047                         // No one else ever edited this page
3048                         return array( array( 'cantrollback' ) );
3049                 } elseif ( $s->rev_deleted & Revision::DELETED_TEXT
3050                         || $s->rev_deleted & Revision::DELETED_USER
3051                 ) {
3052                         // Only admins can see this text
3053                         return array( array( 'notvisiblerev' ) );
3054                 }
3055
3056                 // Set patrolling and bot flag on the edits, which gets rollbacked.
3057                 // This is done before the rollback edit to have patrolling also on failure (bug 62157).
3058                 $set = array();
3059                 if ( $bot && $guser->isAllowed( 'markbotedits' ) ) {
3060                         // Mark all reverted edits as bot
3061                         $set['rc_bot'] = 1;
3062                 }
3063
3064                 if ( $wgUseRCPatrol ) {
3065                         // Mark all reverted edits as patrolled
3066                         $set['rc_patrolled'] = 1;
3067                 }
3068
3069                 if ( count( $set ) ) {
3070                         $dbw->update( 'recentchanges', $set,
3071                                 array( /* WHERE */
3072                                         'rc_cur_id' => $current->getPage(),
3073                                         'rc_user_text' => $current->getUserText(),
3074                                         'rc_timestamp > ' . $dbw->addQuotes( $s->rev_timestamp ),
3075                                 ), __METHOD__
3076                         );
3077                 }
3078
3079                 // Generate the edit summary if necessary
3080                 $target = Revision::newFromId( $s->rev_id, Revision::READ_LATEST );
3081                 if ( empty( $summary ) ) {
3082                         if ( $from == '' ) { // no public user name
3083                                 $summary = wfMessage( 'revertpage-nouser' );
3084                         } else {
3085                                 $summary = wfMessage( 'revertpage' );
3086                         }
3087                 }
3088
3089                 // Allow the custom summary to use the same args as the default message
3090                 $args = array(
3091                         $target->getUserText(), $from, $s->rev_id,
3092                         $wgContLang->timeanddate( wfTimestamp( TS_MW, $s->rev_timestamp ) ),
3093                         $current->getId(), $wgContLang->timeanddate( $current->getTimestamp() )
3094                 );
3095                 if ( $summary instanceof Message ) {
3096                         $summary = $summary->params( $args )->inContentLanguage()->text();
3097                 } else {
3098                         $summary = wfMsgReplaceArgs( $summary, $args );
3099                 }
3100
3101                 // Trim spaces on user supplied text
3102                 $summary = trim( $summary );
3103
3104                 // Truncate for whole multibyte characters.
3105                 $summary = $wgContLang->truncate( $summary, 255 );
3106
3107                 // Save
3108                 $flags = EDIT_UPDATE;
3109
3110                 if ( $guser->isAllowed( 'minoredit' ) ) {
3111                         $flags |= EDIT_MINOR;
3112                 }
3113
3114                 if ( $bot && ( $guser->isAllowedAny( 'markbotedits', 'bot' ) ) ) {
3115                         $flags |= EDIT_FORCE_BOT;
3116                 }
3117
3118                 // Actually store the edit
3119                 $status = $this->doEditContent(
3120                         $target->getContent(),
3121                         $summary,
3122                         $flags,
3123                         $target->getId(),
3124                         $guser
3125                 );
3126
3127                 if ( !$status->isOK() ) {
3128                         return $status->getErrorsArray();
3129                 }
3130
3131                 // raise error, when the edit is an edit without a new version
3132                 if ( empty( $status->value['revision'] ) ) {
3133                         $resultDetails = array( 'current' => $current );
3134                         return array( array( 'alreadyrolled',
3135                                         htmlspecialchars( $this->mTitle->getPrefixedText() ),
3136                                         htmlspecialchars( $fromP ),
3137                                         htmlspecialchars( $current->getUserText() )
3138                         ) );
3139                 }
3140
3141                 $revId = $status->value['revision']->getId();
3142
3143                 Hooks::run( 'ArticleRollbackComplete', array( $this, $guser, $target, $current ) );
3144
3145                 $resultDetails = array(
3146                         'summary' => $summary,
3147                         'current' => $current,
3148                         'target' => $target,
3149                         'newid' => $revId
3150                 );
3151
3152                 return array();
3153         }
3154
3155         /**
3156          * The onArticle*() functions are supposed to be a kind of hooks
3157          * which should be called whenever any of the specified actions
3158          * are done.
3159          *
3160          * This is a good place to put code to clear caches, for instance.
3161          *
3162          * This is called on page move and undelete, as well as edit
3163          *
3164          * @param Title $title
3165          */
3166         public static function onArticleCreate( Title $title ) {
3167                 // Update existence markers on article/talk tabs...
3168                 $other = $title->getOtherPage();
3169
3170                 $other->invalidateCache();
3171                 $other->purgeSquid();
3172
3173                 $title->touchLinks();
3174                 $title->purgeSquid();
3175                 $title->deleteTitleProtection();
3176         }
3177
3178         /**
3179          * Clears caches when article is deleted
3180          *
3181          * @param Title $title
3182          */
3183         public static function onArticleDelete( Title $title ) {
3184                 // Update existence markers on article/talk tabs...
3185                 $other = $title->getOtherPage();
3186
3187                 $other->invalidateCache();
3188                 $other->purgeSquid();
3189
3190                 $title->touchLinks();
3191                 $title->purgeSquid();
3192
3193                 // File cache
3194                 HTMLFileCache::clearFileCache( $title );
3195                 InfoAction::invalidateCache( $title );
3196
3197                 // Messages
3198                 if ( $title->getNamespace() == NS_MEDIAWIKI ) {
3199                         MessageCache::singleton()->replace( $title->getDBkey(), false );
3200                 }
3201
3202                 // Images
3203                 if ( $title->getNamespace() == NS_FILE ) {
3204                         $update = new HTMLCacheUpdate( $title, 'imagelinks' );
3205                         $update->doUpdate();
3206                 }
3207
3208                 // User talk pages
3209                 if ( $title->getNamespace() == NS_USER_TALK ) {
3210                         $user = User::newFromName( $title->getText(), false );
3211                         if ( $user ) {
3212                                 $user->setNewtalk( false );
3213                         }
3214                 }
3215
3216                 // Image redirects
3217                 RepoGroup::singleton()->getLocalRepo()->invalidateImageRedirect( $title );
3218         }
3219
3220         /**
3221          * Purge caches on page update etc
3222          *
3223          * @param Title $title
3224          */
3225         public static function onArticleEdit( Title $title ) {
3226                 // Invalidate caches of articles which include this page
3227                 DeferredUpdates::addHTMLCacheUpdate( $title, 'templatelinks' );
3228
3229                 // Invalidate the caches of all pages which redirect here
3230                 DeferredUpdates::addHTMLCacheUpdate( $title, 'redirect' );
3231
3232                 // Purge squid for this page only
3233                 $title->purgeSquid();
3234
3235                 // Clear file cache for this page only
3236                 HTMLFileCache::clearFileCache( $title );
3237                 InfoAction::invalidateCache( $title );
3238         }
3239
3240         /**#@-*/
3241
3242         /**
3243          * Returns a list of categories this page is a member of.
3244          * Results will include hidden categories
3245          *
3246          * @return TitleArray
3247          */
3248         public function getCategories() {
3249                 $id = $this->getId();
3250                 if ( $id == 0 ) {
3251                         return TitleArray::newFromResult( new FakeResultWrapper( array() ) );
3252                 }
3253
3254                 $dbr = wfGetDB( DB_SLAVE );
3255                 $res = $dbr->select( 'categorylinks',
3256                         array( 'cl_to AS page_title, ' . NS_CATEGORY . ' AS page_namespace' ),
3257                         // Have to do that since DatabaseBase::fieldNamesWithAlias treats numeric indexes
3258                         // as not being aliases, and NS_CATEGORY is numeric
3259                         array( 'cl_from' => $id ),
3260                         __METHOD__ );
3261
3262                 return TitleArray::newFromResult( $res );
3263         }
3264
3265         /**
3266          * Returns a list of hidden categories this page is a member of.
3267          * Uses the page_props and categorylinks tables.
3268          *
3269          * @return array Array of Title objects
3270          */
3271         public function getHiddenCategories() {
3272                 $result = array();
3273                 $id = $this->getId();
3274
3275                 if ( $id == 0 ) {
3276                         return array();
3277                 }
3278
3279                 $dbr = wfGetDB( DB_SLAVE );
3280                 $res = $dbr->select( array( 'categorylinks', 'page_props', 'page' ),
3281                         array( 'cl_to' ),
3282                         array( 'cl_from' => $id, 'pp_page=page_id', 'pp_propname' => 'hiddencat',
3283                                 'page_namespace' => NS_CATEGORY, 'page_title=cl_to' ),
3284                         __METHOD__ );
3285
3286                 if ( $res !== false ) {
3287                         foreach ( $res as $row ) {
3288                                 $result[] = Title::makeTitle( NS_CATEGORY, $row->cl_to );
3289                         }
3290                 }
3291
3292                 return $result;
3293         }
3294
3295         /**
3296          * Return an applicable autosummary if one exists for the given edit.
3297          * @param string|null $oldtext The previous text of the page.
3298          * @param string|null $newtext The submitted text of the page.
3299          * @param int $flags Bitmask: a bitmask of flags submitted for the edit.
3300          * @return string An appropriate autosummary, or an empty string.
3301          *
3302          * @deprecated since 1.21, use ContentHandler::getAutosummary() instead
3303          */
3304         public static function getAutosummary( $oldtext, $newtext, $flags ) {
3305                 // NOTE: stub for backwards-compatibility. assumes the given text is
3306                 // wikitext. will break horribly if it isn't.
3307
3308                 ContentHandler::deprecated( __METHOD__, '1.21' );
3309
3310                 $handler = ContentHandler::getForModelID( CONTENT_MODEL_WIKITEXT );
3311                 $oldContent = is_null( $oldtext ) ? null : $handler->unserializeContent( $oldtext );
3312                 $newContent = is_null( $newtext ) ? null : $handler->unserializeContent( $newtext );
3313
3314                 return $handler->getAutosummary( $oldContent, $newContent, $flags );
3315         }
3316
3317         /**
3318          * Auto-generates a deletion reason
3319          *
3320          * @param bool &$hasHistory Whether the page has a history
3321          * @return string|bool String containing deletion reason or empty string, or boolean false
3322          *    if no revision occurred
3323          */
3324         public function getAutoDeleteReason( &$hasHistory ) {
3325                 return $this->getContentHandler()->getAutoDeleteReason( $this->getTitle(), $hasHistory );
3326         }
3327
3328         /**
3329          * Update all the appropriate counts in the category table, given that
3330          * we've added the categories $added and deleted the categories $deleted.
3331          *
3332          * @param array $added The names of categories that were added
3333          * @param array $deleted The names of categories that were deleted
3334          */
3335         public function updateCategoryCounts( array $added, array $deleted ) {
3336                 $that = $this;
3337                 $method = __METHOD__;
3338                 $dbw = wfGetDB( DB_MASTER );
3339
3340                 // Do this at the end of the commit to reduce lock wait timeouts
3341                 $dbw->onTransactionPreCommitOrIdle(
3342                         function () use ( $dbw, $that, $method, $added, $deleted ) {
3343                                 $ns = $that->getTitle()->getNamespace();
3344
3345                                 $addFields = array( 'cat_pages = cat_pages + 1' );
3346                                 $removeFields = array( 'cat_pages = cat_pages - 1' );
3347                                 if ( $ns == NS_CATEGORY ) {
3348                                         $addFields[] = 'cat_subcats = cat_subcats + 1';
3349                                         $removeFields[] = 'cat_subcats = cat_subcats - 1';
3350                                 } elseif ( $ns == NS_FILE ) {
3351                                         $addFields[] = 'cat_files = cat_files + 1';
3352                                         $removeFields[] = 'cat_files = cat_files - 1';
3353                                 }
3354
3355                                 if ( count( $added ) ) {
3356                                         $insertRows = array();
3357                                         foreach ( $added as $cat ) {
3358                                                 $insertRows[] = array(
3359                                                         'cat_title'   => $cat,
3360                                                         'cat_pages'   => 1,
3361                                                         'cat_subcats' => ( $ns == NS_CATEGORY ) ? 1 : 0,
3362                                                         'cat_files'   => ( $ns == NS_FILE ) ? 1 : 0,
3363                                                 );
3364                                         }
3365                                         $dbw->upsert(
3366                                                 'category',
3367                                                 $insertRows,
3368                                                 array( 'cat_title' ),
3369                                                 $addFields,
3370                                                 $method
3371                                         );
3372                                 }
3373
3374                                 if ( count( $deleted ) ) {
3375                                         $dbw->update(
3376                                                 'category',
3377                                                 $removeFields,
3378                                                 array( 'cat_title' => $deleted ),
3379                                                 $method
3380                                         );
3381                                 }
3382
3383                                 foreach ( $added as $catName ) {
3384                                         $cat = Category::newFromName( $catName );
3385                                         Hooks::run( 'CategoryAfterPageAdded', array( $cat, $that ) );
3386                                 }
3387
3388                                 foreach ( $deleted as $catName ) {
3389                                         $cat = Category::newFromName( $catName );
3390                                         Hooks::run( 'CategoryAfterPageRemoved', array( $cat, $that ) );
3391                                 }
3392                         }
3393                 );
3394         }
3395
3396         /**
3397          * Opportunistically enqueue link update jobs given fresh parser output if useful
3398          *
3399          * @param ParserOutput $parserOutput Current version page output
3400          * @since 1.25
3401          */
3402         public function triggerOpportunisticLinksUpdate( ParserOutput $parserOutput ) {
3403                 if ( wfReadOnly() ) {
3404                         return;
3405                 }
3406
3407                 if ( !Hooks::run( 'OpportunisticLinksUpdate', array( $this, $this->mTitle, $parserOutput ) ) ) {
3408                         return;
3409                 }
3410
3411                 if ( $this->mTitle->areRestrictionsCascading() ) {
3412                         // If the page is cascade protecting, the links should really be up-to-date
3413                         $params = array( 'prioritize' => true );
3414                 } elseif ( $parserOutput->hasDynamicContent() ) {
3415                         // Assume the output contains time/random based magic words
3416                         $params = array();
3417                 } else {
3418                         // If the inclusions are deterministic, the edit-triggered link jobs are enough
3419                         return;
3420                 }
3421
3422                 // Check if the last link refresh was before page_touched
3423                 if ( $this->getLinksTimestamp() < $this->getTouched() ) {
3424                         $params['isOpportunistic'] = true;
3425                         $params['rootJobTimestamp'] = $parserOutput->getCacheTime();
3426
3427                         JobQueueGroup::singleton()->lazyPush( EnqueueJob::newFromLocalJobs(
3428                                 new JobSpecification( 'refreshLinks', $params,
3429                                         array( 'removeDuplicates' => true ), $this->mTitle )
3430                         ) );
3431                 }
3432         }
3433
3434         /**
3435          * Return a list of templates used by this article.
3436          * Uses the templatelinks table
3437          *
3438          * @deprecated since 1.19; use Title::getTemplateLinksFrom()
3439          * @return array Array of Title objects
3440          */
3441         public function getUsedTemplates() {
3442                 return $this->mTitle->getTemplateLinksFrom();
3443         }
3444
3445         /**
3446          * This function is called right before saving the wikitext,
3447          * so we can do things like signatures and links-in-context.
3448          *
3449          * @deprecated since 1.19; use Parser::preSaveTransform() instead
3450          * @param string $text Article contents
3451          * @param User $user User doing the edit
3452          * @param ParserOptions $popts Parser options, default options for
3453          *   the user loaded if null given
3454          * @return string Article contents with altered wikitext markup (signatures
3455          *      converted, {{subst:}}, templates, etc.)
3456          */
3457         public function preSaveTransform( $text, User $user = null, ParserOptions $popts = null ) {
3458                 global $wgParser, $wgUser;
3459
3460                 wfDeprecated( __METHOD__, '1.19' );
3461
3462                 $user = is_null( $user ) ? $wgUser : $user;
3463
3464                 if ( $popts === null ) {
3465                         $popts = ParserOptions::newFromUser( $user );
3466                 }
3467
3468                 return $wgParser->preSaveTransform( $text, $this->mTitle, $user, $popts );
3469         }
3470
3471         /**
3472          * Update the article's restriction field, and leave a log entry.
3473          *
3474          * @deprecated since 1.19
3475          * @param array $limit Set of restriction keys
3476          * @param string $reason
3477          * @param int &$cascade Set to false if cascading protection isn't allowed.
3478          * @param array $expiry Per restriction type expiration
3479          * @param User $user The user updating the restrictions
3480          * @return bool True on success
3481          */
3482         public function updateRestrictions(
3483                 $limit = array(), $reason = '', &$cascade = 0, $expiry = array(), User $user = null
3484         ) {
3485                 global $wgUser;
3486
3487                 $user = is_null( $user ) ? $wgUser : $user;
3488
3489                 return $this->doUpdateRestrictions( $limit, $expiry, $cascade, $reason, $user )->isOK();
3490         }
3491
3492         /**
3493          * Returns a list of updates to be performed when this page is deleted. The
3494          * updates should remove any information about this page from secondary data
3495          * stores such as links tables.
3496          *
3497          * @param Content|null $content Optional Content object for determining the
3498          *   necessary updates.
3499          * @return array An array of DataUpdates objects
3500          */
3501         public function getDeletionUpdates( Content $content = null ) {
3502                 if ( !$content ) {
3503                         // load content object, which may be used to determine the necessary updates
3504                         // XXX: the content may not be needed to determine the updates, then this would be overhead.
3505                         $content = $this->getContent( Revision::RAW );
3506                 }
3507
3508                 if ( !$content ) {
3509                         $updates = array();
3510                 } else {
3511                         $updates = $content->getDeletionUpdates( $this );
3512                 }
3513
3514                 Hooks::run( 'WikiPageDeletionUpdates', array( $this, $content, &$updates ) );
3515                 return $updates;
3516         }
3517 }