includes/Article.php

   1 <?php
   2 /**
   3  * File for articles
   4  * @file
   5  */
   6
   7 /**
   8  * Class for viewing MediaWiki article and history.
   9  *
  10  * This maintains WikiPage functions for backwards compatibility.
  11  *
  12  * @TODO: move and rewrite code to an Action class
  13  *
  14  * See design.txt for an overview.
  15  * Note: edit user interface and cache support functions have been
  16  * moved to separate EditPage and HTMLFileCache classes.
  17  *
  18  * @internal documentation reviewed 15 Mar 2010
  19  */
  20 class Article extends Page {
  21         /**@{{
  22          * @private
  23          */
  24
  25         /**
  26          * @var RequestContext
  27          */
  28         protected $mContext;
  29
  30         /**
  31          * @var WikiPage
  32          */
  33         protected $mPage;
  34
  35         var $mContent;                    // !<
  36         var $mContentLoaded = false;      // !<
  37         var $mOldId;                      // !<
  38
  39         /**
  40          * @var Title
  41          */
  42         var $mRedirectedFrom = null;
  43
  44         /**
  45          * @var mixed: boolean false or URL string
  46          */
  47         var $mRedirectUrl = false;        // !<
  48         var $mRevIdFetched = 0;           // !<
  49
  50         /**
  51          * @var Revision
  52          */
  53         var $mRevision = null;
  54
  55         /**
  56          * @var ParserOutput
  57          */
  58         var $mParserOutput;
  59
  60         /**@}}*/
  61
  62         /**
  63          * Constructor and clear the article
  64          * @param $title Title Reference to a Title object.
  65          * @param $oldId Integer revision ID, null to fetch from request, zero for current
  66          */
  67         public function __construct( Title $title, $oldId = null ) {
  68                 $this->mOldId = $oldId;
  69                 $this->mPage = $this->newPage( $title );
  70         }
  71
  72         protected function newPage( Title $title ) {
  73                 return new WikiPage( $title );
  74         }
  75
  76         /**
  77          * Constructor from a page id
  78          * @param $id Int article ID to load
  79          */
  80         public static function newFromID( $id ) {
  81                 $t = Title::newFromID( $id );
  82                 # @todo FIXME: Doesn't inherit right
  83                 return $t == null ? null : new self( $t );
  84                 # return $t == null ? null : new static( $t ); // PHP 5.3
  85         }
  86
  87         /**
  88          * Create an Article object of the appropriate class for the given page.
  89          *
  90          * @param $title Title
  91          * @param $context RequestContext
  92          * @return Article object
  93          */
  94         public static function newFromTitle( $title, RequestContext $context ) {
  95                 if ( NS_MEDIA == $title->getNamespace() ) {
  96                         // FIXME: where should this go?
  97                         $title = Title::makeTitle( NS_FILE, $title->getDBkey() );
  98                 }
  99
 100                 $page = null;
 101                 wfRunHooks( 'ArticleFromTitle', array( &$title, &$page ) );
 102                 if ( !$page ) {
 103                         switch( $title->getNamespace() ) {
 104                                 case NS_FILE:
 105                                         $page = new ImagePage( $title );
 106                                         break;
 107                                 case NS_CATEGORY:
 108                                         $page = new CategoryPage( $title );
 109                                         break;
 110                                 default:
 111                                         $page = new Article( $title );
 112                         }
 113                 }
 114                 $page->setContext( $context );
 115
 116                 return $page;
 117         }
 118
 119         /**
 120          * Tell the page view functions that this view was redirected
 121          * from another page on the wiki.
 122          * @param $from Title object.
 123          */
 124         public function setRedirectedFrom( Title $from ) {
 125                 $this->mRedirectedFrom = $from;
 126         }
 127
 128         /**
 129          * Get the title object of the article
 130          * @return Title object of this page
 131          */
 132         public function getTitle() {
 133                 return $this->mPage->getTitle();
 134         }
 135
 136         /**
 137          * Clear the object
 138          * @todo FIXME: Shouldn't this be public?
 139          * @private
 140          */
 141         public function clear() {
 142                 $this->mContentLoaded = false;
 143
 144                 $this->mRedirectedFrom = null; # Title object if set
 145                 $this->mRevIdFetched = 0;
 146                 $this->mRedirectUrl = false;
 147
 148                 $this->mPage->clear();
 149         }
 150
 151         /**
 152          * Note that getContent/loadContent do not follow redirects anymore.
 153          * If you need to fetch redirectable content easily, try
 154          * the shortcut in Article::followRedirect()
 155          *
 156          * This function has side effects! Do not use this function if you
 157          * only want the real revision text if any.
 158          *
 159          * @return Return the text of this revision
 160          */
 161         public function getContent() {
 162                 global $wgUser;
 163
 164                 wfProfileIn( __METHOD__ );
 165
 166                 if ( $this->mPage->getID() === 0 ) {
 167                         # If this is a MediaWiki:x message, then load the messages
 168                         # and return the message value for x.
 169                         if ( $this->getTitle()->getNamespace() == NS_MEDIAWIKI ) {
 170                                 $text = $this->getTitle()->getDefaultMessageText();
 171                                 if ( $text === false ) {
 172                                         $text = '';
 173                                 }
 174                         } else {
 175                                 $text = wfMsgExt( $wgUser->isLoggedIn() ? 'noarticletext' : 'noarticletextanon', 'parsemag' );
 176                         }
 177                         wfProfileOut( __METHOD__ );
 178
 179                         return $text;
 180                 } else {
 181                         $this->loadContent();
 182                         wfProfileOut( __METHOD__ );
 183
 184                         return $this->mContent;
 185                 }
 186         }
 187
 188         /**
 189          * @return int The oldid of the article that is to be shown, 0 for the
 190          *             current revision
 191          */
 192         public function getOldID() {
 193                 if ( is_null( $this->mOldId ) ) {
 194                         $this->mOldId = $this->getOldIDFromRequest();
 195                 }
 196
 197                 return $this->mOldId;
 198         }
 199
 200         /**
 201          * Sets $this->mRedirectUrl to a correct URL if the query parameters are incorrect
 202          *
 203          * @return int The old id for the request
 204          */
 205         public function getOldIDFromRequest() {
 206                 global $wgRequest;
 207
 208                 $this->mRedirectUrl = false;
 209
 210                 $oldid = $wgRequest->getVal( 'oldid' );
 211
 212                 if ( isset( $oldid ) ) {
 213                         $oldid = intval( $oldid );
 214                         if ( $wgRequest->getVal( 'direction' ) == 'next' ) {
 215                                 $nextid = $this->getTitle()->getNextRevisionID( $oldid );
 216                                 if ( $nextid ) {
 217                                         $oldid = $nextid;
 218                                 } else {
 219                                         $this->mRedirectUrl = $this->getTitle()->getFullURL( 'redirect=no' );
 220                                 }
 221                         } elseif ( $wgRequest->getVal( 'direction' ) == 'prev' ) {
 222                                 $previd = $this->getTitle()->getPreviousRevisionID( $oldid );
 223                                 if ( $previd ) {
 224                                         $oldid = $previd;
 225                                 }
 226                         }
 227                 }
 228
 229                 if ( !$oldid ) {
 230                         $oldid = 0;
 231                 }
 232
 233                 return $oldid;
 234         }
 235
 236         /**
 237          * Load the revision (including text) into this object
 238          */
 239         function loadContent() {
 240                 if ( $this->mContentLoaded ) {
 241                         return;
 242                 }
 243
 244                 wfProfileIn( __METHOD__ );
 245
 246                 $this->fetchContent( $this->getOldID() );
 247
 248                 wfProfileOut( __METHOD__ );
 249         }
 250
 251         /**
 252          * Get text of an article from database
 253          * Does *NOT* follow redirects.
 254          *
 255          * @param $oldid Int: 0 for whatever the latest revision is
 256          * @return mixed string containing article contents, or false if null
 257          */
 258         function fetchContent( $oldid = 0 ) {
 259                 if ( $this->mContentLoaded ) {
 260                         return $this->mContent;
 261                 }
 262
 263                 # Pre-fill content with error message so that if something
 264                 # fails we'll have something telling us what we intended.
 265                 $t = $this->getTitle()->getPrefixedText();
 266                 $d = $oldid ? wfMsgExt( 'missingarticle-rev', array( 'escape' ), $oldid ) : '';
 267                 $this->mContent = wfMsgNoTrans( 'missing-article', $t, $d ) ;
 268
 269                 if ( $oldid ) {
 270                         $revision = Revision::newFromId( $oldid );
 271                         if ( !$revision ) {
 272                                 wfDebug( __METHOD__ . " failed to retrieve specified revision, id $oldid\n" );
 273                                 return false;
 274                         }
 275                         // Revision title doesn't match the page title given?
 276                         if ( $this->mPage->getID() != $revision->getPage() ) {
 277                                 $function = array( get_class( $this->mPage ), 'newFromID' );
 278                                 $this->mPage = call_user_func( $function, $revision->getPage() );
 279                                 if ( !$this->mPage->getId() ) {
 280                                         wfDebug( __METHOD__ . " failed to get page data linked to revision id $oldid\n" );
 281                                         return false;
 282                                 }
 283                         }
 284                 } else {
 285                         if ( !$this->mPage->getLatest() ) {
 286                                 wfDebug( __METHOD__ . " failed to find page data for title " . $this->getTitle()->getPrefixedText() . "\n" );
 287                                 return false;
 288                         }
 289
 290                         $revision = $this->mPage->getRevision();
 291                         if ( !$revision ) {
 292                                 wfDebug( __METHOD__ . " failed to retrieve current page, rev_id " . $this->mPage->getLatest() . "\n" );
 293                                 return false;
 294                         }
 295                 }
 296
 297                 // @todo FIXME: Horrible, horrible! This content-loading interface just plain sucks.
 298                 // We should instead work with the Revision object when we need it...
 299                 $this->mContent   = $revision->getText( Revision::FOR_THIS_USER ); // Loads if user is allowed
 300
 301                 $this->mRevIdFetched = $revision->getId();
 302                 $this->mContentLoaded = true;
 303                 $this->mRevision =& $revision;
 304
 305                 wfRunHooks( 'ArticleAfterFetchContent', array( &$this, &$this->mContent ) );
 306
 307                 return $this->mContent;
 308         }
 309
 310         /**
 311          * No-op
 312          * @deprecated since 1.18
 313          */
 314         public function forUpdate() {
 315                 wfDeprecated( __METHOD__ );
 316         }
 317
 318         /**
 319          * Returns true if the currently-referenced revision is the current edit
 320          * to this page (and it exists).
 321          * @return bool
 322          */
 323         public function isCurrent() {
 324                 # If no oldid, this is the current version.
 325                 if ( $this->getOldID() == 0 ) {
 326                         return true;
 327                 }
 328
 329                 return $this->mPage->exists() && $this->mRevision && $this->mRevision->isCurrent();
 330         }
 331
 332         /**
 333          * Use this to fetch the rev ID used on page views
 334          *
 335          * @return int revision ID of last article revision
 336          */
 337         public function getRevIdFetched() {
 338                 if ( $this->mRevIdFetched ) {
 339                         return $this->mRevIdFetched;
 340                 } else {
 341                         return $this->mPage->getLatest();
 342                 }
 343         }
 344
 345         /**
 346          * This is the default action of the index.php entry point: just view the
 347          * page of the given title.
 348          */
 349         public function view() {
 350                 global $wgUser, $wgOut, $wgRequest, $wgParser;
 351                 global $wgUseFileCache, $wgUseETag;
 352
 353                 wfProfileIn( __METHOD__ );
 354
 355                 # Get variables from query string
 356                 $oldid = $this->getOldID();
 357
 358                 # getOldID may want us to redirect somewhere else
 359                 if ( $this->mRedirectUrl ) {
 360                         $wgOut->redirect( $this->mRedirectUrl );
 361                         wfDebug( __METHOD__ . ": redirecting due to oldid\n" );
 362                         wfProfileOut( __METHOD__ );
 363
 364                         return;
 365                 }
 366
 367                 $wgOut->setArticleFlag( true );
 368                 # Set page title (may be overridden by DISPLAYTITLE)
 369                 $wgOut->setPageTitle( $this->getTitle()->getPrefixedText() );
 370
 371                 # If we got diff in the query, we want to see a diff page instead of the article.
 372                 if ( $wgRequest->getCheck( 'diff' ) ) {
 373                         wfDebug( __METHOD__ . ": showing diff page\n" );
 374                         $this->showDiffPage();
 375                         wfProfileOut( __METHOD__ );
 376
 377                         return;
 378                 }
 379
 380                 # Allow frames by default
 381                 $wgOut->allowClickjacking();
 382
 383                 $parserCache = ParserCache::singleton();
 384
 385                 $parserOptions = $this->mPage->getParserOptions();
 386                 # Render printable version, use printable version cache
 387                 if ( $wgOut->isPrintable() ) {
 388                         $parserOptions->setIsPrintable( true );
 389                         $parserOptions->setEditSection( false );
 390                 } elseif ( $wgUseETag && !$this->getTitle()->quickUserCan( 'edit' ) ) {
 391                         $parserOptions->setEditSection( false );
 392                 }
 393
 394                 # Try client and file cache
 395                 if ( $oldid === 0 && $this->mPage->checkTouched() ) {
 396                         if ( $wgUseETag ) {
 397                                 $wgOut->setETag( $parserCache->getETag( $this, $parserOptions ) );
 398                         }
 399
 400                         # Is it client cached?
 401                         if ( $wgOut->checkLastModified( $this->mPage->getTouched() ) ) {
 402                                 wfDebug( __METHOD__ . ": done 304\n" );
 403                                 wfProfileOut( __METHOD__ );
 404
 405                                 return;
 406                         # Try file cache
 407                         } elseif ( $wgUseFileCache && $this->tryFileCache() ) {
 408                                 wfDebug( __METHOD__ . ": done file cache\n" );
 409                                 # tell wgOut that output is taken care of
 410                                 $wgOut->disable();
 411                                 $this->mPage->viewUpdates();
 412                                 wfProfileOut( __METHOD__ );
 413
 414                                 return;
 415                         }
 416                 }
 417
 418                 if ( !$wgUseETag && !$this->getTitle()->quickUserCan( 'edit' ) ) {
 419                         $parserOptions->setEditSection( false );
 420                 }
 421
 422                 # Should the parser cache be used?
 423                 $useParserCache = $this->useParserCache( $oldid );
 424                 wfDebug( 'Article::view using parser cache: ' . ( $useParserCache ? 'yes' : 'no' ) . "\n" );
 425                 if ( $wgUser->getStubThreshold() ) {
 426                         wfIncrStats( 'pcache_miss_stub' );
 427                 }
 428
 429                 $wasRedirected = $this->showRedirectedFromHeader();
 430                 $this->showNamespaceHeader();
 431
 432                 # Iterate through the possible ways of constructing the output text.
 433                 # Keep going until $outputDone is set, or we run out of things to do.
 434                 $pass = 0;
 435                 $outputDone = false;
 436                 $this->mParserOutput = false;
 437
 438                 while ( !$outputDone && ++$pass ) {
 439                         switch( $pass ) {
 440                                 case 1:
 441                                         wfRunHooks( 'ArticleViewHeader', array( &$this, &$outputDone, &$useParserCache ) );
 442                                         break;
 443                                 case 2:
 444                                         # Try the parser cache
 445                                         if ( $useParserCache ) {
 446                                                 $this->mParserOutput = $parserCache->get( $this, $parserOptions );
 447
 448                                                 if ( $this->mParserOutput !== false ) {
 449                                                         wfDebug( __METHOD__ . ": showing parser cache contents\n" );
 450                                                         $wgOut->addParserOutput( $this->mParserOutput );
 451                                                         # Ensure that UI elements requiring revision ID have
 452                                                         # the correct version information.
 453                                                         $wgOut->setRevisionId( $this->mPage->getLatest() );
 454                                                         $outputDone = true;
 455                                                         # Preload timestamp to avoid a DB hit
 456                                                         if ( isset( $this->mParserOutput->mTimestamp ) ) {
 457                                                                 $this->mPage->setTimestamp( $this->mParserOutput->mTimestamp );
 458                                                         }
 459                                                 }
 460                                         }
 461                                         break;
 462                                 case 3:
 463                                         $text = $this->getContent();
 464                                         if ( $text === false || $this->mPage->getID() == 0 ) {
 465                                                 wfDebug( __METHOD__ . ": showing missing article\n" );
 466                                                 $this->showMissingArticle();
 467                                                 wfProfileOut( __METHOD__ );
 468                                                 return;
 469                                         }
 470
 471                                         # Another whitelist check in case oldid is altering the title
 472                                         if ( !$this->getTitle()->userCanRead() ) {
 473                                                 wfDebug( __METHOD__ . ": denied on secondary read check\n" );
 474                                                 $wgOut->loginToUse();
 475                                                 $wgOut->output();
 476                                                 $wgOut->disable();
 477                                                 wfProfileOut( __METHOD__ );
 478                                                 return;
 479                                         }
 480
 481                                         # Are we looking at an old revision
 482                                         if ( $oldid && !is_null( $this->mRevision ) ) {
 483                                                 $this->setOldSubtitle( $oldid );
 484
 485                                                 if ( !$this->showDeletedRevisionHeader() ) {
 486                                                         wfDebug( __METHOD__ . ": cannot view deleted revision\n" );
 487                                                         wfProfileOut( __METHOD__ );
 488                                                         return;
 489                                                 }
 490
 491                                                 # If this "old" version is the current, then try the parser cache...
 492                                                 if ( $oldid === $this->mPage->getLatest() && $this->useParserCache( false ) ) {
 493                                                         $this->mParserOutput = $parserCache->get( $this, $parserOptions );
 494                                                         if ( $this->mParserOutput ) {
 495                                                                 wfDebug( __METHOD__ . ": showing parser cache for current rev permalink\n" );
 496                                                                 $wgOut->addParserOutput( $this->mParserOutput );
 497                                                                 $wgOut->setRevisionId( $this->mPage->getLatest() );
 498                                                                 $outputDone = true;
 499                                                                 break;
 500                                                         }
 501                                                 }
 502                                         }
 503
 504                                         # Ensure that UI elements requiring revision ID have
 505                                         # the correct version information.
 506                                         $wgOut->setRevisionId( $this->getRevIdFetched() );
 507
 508                                         # Pages containing custom CSS or JavaScript get special treatment
 509                                         if ( $this->getTitle()->isCssOrJsPage() || $this->getTitle()->isCssJsSubpage() ) {
 510                                                 wfDebug( __METHOD__ . ": showing CSS/JS source\n" );
 511                                                 $this->showCssOrJsPage();
 512                                                 $outputDone = true;
 513                                         } else {
 514                                                 $rt = Title::newFromRedirectArray( $text );
 515                                                 if ( $rt ) {
 516                                                         wfDebug( __METHOD__ . ": showing redirect=no page\n" );
 517                                                         # Viewing a redirect page (e.g. with parameter redirect=no)
 518                                                         # Don't append the subtitle if this was an old revision
 519                                                         $wgOut->addHTML( $this->viewRedirect( $rt, !$wasRedirected && $this->isCurrent() ) );
 520                                                         # Parse just to get categories, displaytitle, etc.
 521                                                         $this->mParserOutput = $wgParser->parse( $text, $this->getTitle(), $parserOptions );
 522                                                         $wgOut->addParserOutputNoText( $this->mParserOutput );
 523                                                         $outputDone = true;
 524                                                 }
 525                                         }
 526                                         break;
 527                                 case 4:
 528                                         # Run the parse, protected by a pool counter
 529                                         wfDebug( __METHOD__ . ": doing uncached parse\n" );
 530
 531                                         $key = $parserCache->getKey( $this, $parserOptions );
 532                                         $poolArticleView = new PoolWorkArticleView( $this, $key, $useParserCache, $parserOptions );
 533
 534                                         if ( !$poolArticleView->execute() ) {
 535                                                 # Connection or timeout error
 536                                                 wfProfileOut( __METHOD__ );
 537                                                 return;
 538                                         } else {
 539                                                 $outputDone = true;
 540                                         }
 541                                         break;
 542                                 # Should be unreachable, but just in case...
 543                                 default:
 544                                         break 2;
 545                         }
 546                 }
 547
 548                 # Adjust the title if it was set by displaytitle, -{T|}- or language conversion
 549                 if ( $this->mParserOutput ) {
 550                         $titleText = $this->mParserOutput->getTitleText();
 551
 552                         if ( strval( $titleText ) !== '' ) {
 553                                 $wgOut->setPageTitle( $titleText );
 554                         }
 555                 }
 556
 557                 # For the main page, overwrite the <title> element with the con-
 558                 # tents of 'pagetitle-view-mainpage' instead of the default (if
 559                 # that's not empty).
 560                 # This message always exists because it is in the i18n files
 561                 if ( $this->getTitle()->equals( Title::newMainPage() ) ) {
 562                         $msg = wfMessage( 'pagetitle-view-mainpage' )->inContentLanguage();
 563                         if ( !$msg->isDisabled() ) {
 564                                 $wgOut->setHTMLTitle( $msg->title( $this->getTitle() )->text() );
 565                         }
 566                 }
 567
 568                 # Now that we've filled $this->mParserOutput, we know whether
 569                 # there are any __NOINDEX__ tags on the page
 570                 $policy = $this->getRobotPolicy( 'view' );
 571                 $wgOut->setIndexPolicy( $policy['index'] );
 572                 $wgOut->setFollowPolicy( $policy['follow'] );
 573
 574                 $this->showViewFooter();
 575                 $this->mPage->viewUpdates();
 576                 wfProfileOut( __METHOD__ );
 577         }
 578
 579         /**
 580          * Show a diff page according to current request variables. For use within
 581          * Article::view() only, other callers should use the DifferenceEngine class.
 582          */
 583         public function showDiffPage() {
 584                 global $wgRequest, $wgUser;
 585
 586                 $diff = $wgRequest->getVal( 'diff' );
 587                 $rcid = $wgRequest->getVal( 'rcid' );
 588                 $diffOnly = $wgRequest->getBool( 'diffonly', $wgUser->getOption( 'diffonly' ) );
 589                 $purge = $wgRequest->getVal( 'action' ) == 'purge';
 590                 $unhide = $wgRequest->getInt( 'unhide' ) == 1;
 591                 $oldid = $this->getOldID();
 592
 593                 $de = new DifferenceEngine( $this->getTitle(), $oldid, $diff, $rcid, $purge, $unhide );
 594                 // DifferenceEngine directly fetched the revision:
 595                 $this->mRevIdFetched = $de->mNewid;
 596                 $de->showDiffPage( $diffOnly );
 597
 598                 if ( $diff == 0 || $diff == $this->mPage->getLatest() ) {
 599                         # Run view updates for current revision only
 600                         $this->mPage->viewUpdates();
 601                 }
 602         }
 603
 604         /**
 605          * Show a page view for a page formatted as CSS or JavaScript. To be called by
 606          * Article::view() only.
 607          *
 608          * This is hooked by SyntaxHighlight_GeSHi to do syntax highlighting of these
 609          * page views.
 610          */
 611         protected function showCssOrJsPage() {
 612                 global $wgOut;
 613
 614                 $wgOut->wrapWikiMsg( "<div id='mw-clearyourcache'>\n$1\n</div>", 'clearyourcache' );
 615
 616                 // Give hooks a chance to customise the output
 617                 if ( wfRunHooks( 'ShowRawCssJs', array( $this->mContent, $this->getTitle(), $wgOut ) ) ) {
 618                         // Wrap the whole lot in a <pre> and don't parse
 619                         $m = array();
 620                         preg_match( '!\.(css|js)$!u', $this->getTitle()->getText(), $m );
 621                         $wgOut->addHTML( "<pre class=\"mw-code mw-{$m[1]}\" dir=\"ltr\">\n" );
 622                         $wgOut->addHTML( htmlspecialchars( $this->mContent ) );
 623                         $wgOut->addHTML( "\n</pre>\n" );
 624                 }
 625         }
 626
 627         /**
 628          * Get the robot policy to be used for the current view
 629          * @param $action String the action= GET parameter
 630          * @return Array the policy that should be set
 631          * TODO: actions other than 'view'
 632          */
 633         public function getRobotPolicy( $action ) {
 634                 global $wgOut, $wgArticleRobotPolicies, $wgNamespaceRobotPolicies;
 635                 global $wgDefaultRobotPolicy, $wgRequest;
 636
 637                 $ns = $this->getTitle()->getNamespace();
 638
 639                 if ( $ns == NS_USER || $ns == NS_USER_TALK ) {
 640                         # Don't index user and user talk pages for blocked users (bug 11443)
 641                         if ( !$this->getTitle()->isSubpage() ) {
 642                                 if ( Block::newFromTarget( null, $this->getTitle()->getText() ) instanceof Block ) {
 643                                         return array(
 644                                                 'index'  => 'noindex',
 645                                                 'follow' => 'nofollow'
 646                                         );
 647                                 }
 648                         }
 649                 }
 650
 651                 if ( $this->mPage->getID() === 0 || $this->getOldID() ) {
 652                         # Non-articles (special pages etc), and old revisions
 653                         return array(
 654                                 'index'  => 'noindex',
 655                                 'follow' => 'nofollow'
 656                         );
 657                 } elseif ( $wgOut->isPrintable() ) {
 658                         # Discourage indexing of printable versions, but encourage following
 659                         return array(
 660                                 'index'  => 'noindex',
 661                                 'follow' => 'follow'
 662                         );
 663                 } elseif ( $wgRequest->getInt( 'curid' ) ) {
 664                         # For ?curid=x urls, disallow indexing
 665                         return array(
 666                                 'index'  => 'noindex',
 667                                 'follow' => 'follow'
 668                         );
 669                 }
 670
 671                 # Otherwise, construct the policy based on the various config variables.
 672                 $policy = self::formatRobotPolicy( $wgDefaultRobotPolicy );
 673
 674                 if ( isset( $wgNamespaceRobotPolicies[$ns] ) ) {
 675                         # Honour customised robot policies for this namespace
 676                         $policy = array_merge(
 677                                 $policy,
 678                                 self::formatRobotPolicy( $wgNamespaceRobotPolicies[$ns] )
 679                         );
 680                 }
 681                 if ( $this->getTitle()->canUseNoindex() && is_object( $this->mParserOutput ) && $this->mParserOutput->getIndexPolicy() ) {
 682                         # __INDEX__ and __NOINDEX__ magic words, if allowed. Incorporates
 683                         # a final sanity check that we have really got the parser output.
 684                         $policy = array_merge(
 685                                 $policy,
 686                                 array( 'index' => $this->mParserOutput->getIndexPolicy() )
 687                         );
 688                 }
 689
 690                 if ( isset( $wgArticleRobotPolicies[$this->getTitle()->getPrefixedText()] ) ) {
 691                         # (bug 14900) site config can override user-defined __INDEX__ or __NOINDEX__
 692                         $policy = array_merge(
 693                                 $policy,
 694                                 self::formatRobotPolicy( $wgArticleRobotPolicies[$this->getTitle()->getPrefixedText()] )
 695                         );
 696                 }
 697
 698                 return $policy;
 699         }
 700
 701         /**
 702          * Converts a String robot policy into an associative array, to allow
 703          * merging of several policies using array_merge().
 704          * @param $policy Mixed, returns empty array on null/false/'', transparent
 705          *            to already-converted arrays, converts String.
 706          * @return Array: 'index' => <indexpolicy>, 'follow' => <followpolicy>
 707          */
 708         public static function formatRobotPolicy( $policy ) {
 709                 if ( is_array( $policy ) ) {
 710                         return $policy;
 711                 } elseif ( !$policy ) {
 712                         return array();
 713                 }
 714
 715                 $policy = explode( ',', $policy );
 716                 $policy = array_map( 'trim', $policy );
 717
 718                 $arr = array();
 719                 foreach ( $policy as $var ) {
 720                         if ( in_array( $var, array( 'index', 'noindex' ) ) ) {
 721                                 $arr['index'] = $var;
 722                         } elseif ( in_array( $var, array( 'follow', 'nofollow' ) ) ) {
 723                                 $arr['follow'] = $var;
 724                         }
 725                 }
 726
 727                 return $arr;
 728         }
 729
 730         /**
 731          * If this request is a redirect view, send "redirected from" subtitle to
 732          * $wgOut. Returns true if the header was needed, false if this is not a
 733          * redirect view. Handles both local and remote redirects.
 734          *
 735          * @return boolean
 736          */
 737         public function showRedirectedFromHeader() {
 738                 global $wgOut, $wgRequest, $wgRedirectSources;
 739
 740                 $rdfrom = $wgRequest->getVal( 'rdfrom' );
 741
 742                 if ( isset( $this->mRedirectedFrom ) ) {
 743                         // This is an internally redirected page view.
 744                         // We'll need a backlink to the source page for navigation.
 745                         if ( wfRunHooks( 'ArticleViewRedirect', array( &$this ) ) ) {
 746                                 $redir = Linker::link(
 747                                         $this->mRedirectedFrom,
 748                                         null,
 749                                         array(),
 750                                         array( 'redirect' => 'no' ),
 751                                         array( 'known', 'noclasses' )
 752                                 );
 753
 754                                 $s = wfMsgExt( 'redirectedfrom', array( 'parseinline', 'replaceafter' ), $redir );
 755                                 $wgOut->setSubtitle( $s );
 756
 757                                 // Set the fragment if one was specified in the redirect
 758                                 if ( strval( $this->getTitle()->getFragment() ) != '' ) {
 759                                         $fragment = Xml::escapeJsString( $this->getTitle()->getFragmentForURL() );
 760                                         $wgOut->addInlineScript( "redirectToFragment(\"$fragment\");" );
 761                                 }
 762
 763                                 // Add a <link rel="canonical"> tag
 764                                 $wgOut->addLink( array( 'rel' => 'canonical',
 765                                         'href' => $this->getTitle()->getLocalURL() )
 766                                 );
 767
 768                                 return true;
 769                         }
 770                 } elseif ( $rdfrom ) {
 771                         // This is an externally redirected view, from some other wiki.
 772                         // If it was reported from a trusted site, supply a backlink.
 773                         if ( $wgRedirectSources && preg_match( $wgRedirectSources, $rdfrom ) ) {
 774                                 $redir = Linker::makeExternalLink( $rdfrom, $rdfrom );
 775                                 $s = wfMsgExt( 'redirectedfrom', array( 'parseinline', 'replaceafter' ), $redir );
 776                                 $wgOut->setSubtitle( $s );
 777
 778                                 return true;
 779                         }
 780                 }
 781
 782                 return false;
 783         }
 784
 785         /**
 786          * Show a header specific to the namespace currently being viewed, like
 787          * [[MediaWiki:Talkpagetext]]. For Article::view().
 788          */
 789         public function showNamespaceHeader() {
 790                 global $wgOut;
 791
 792                 if ( $this->getTitle()->isTalkPage() ) {
 793                         if ( !wfMessage( 'talkpageheader' )->isDisabled() ) {
 794                                 $wgOut->wrapWikiMsg( "<div class=\"mw-talkpageheader\">\n$1\n</div>", array( 'talkpageheader' ) );
 795                         }
 796                 }
 797         }
 798
 799         /**
 800          * Show the footer section of an ordinary page view
 801          */
 802         public function showViewFooter() {
 803                 global $wgOut, $wgUseTrackbacks;
 804
 805                 # check if we're displaying a [[User talk:x.x.x.x]] anonymous talk page
 806                 if ( $this->getTitle()->getNamespace() == NS_USER_TALK && IP::isValid( $this->getTitle()->getText() ) ) {
 807                         $wgOut->addWikiMsg( 'anontalkpagetext' );
 808                 }
 809
 810                 # If we have been passed an &rcid= parameter, we want to give the user a
 811                 # chance to mark this new article as patrolled.
 812                 $this->showPatrolFooter();
 813
 814                 # Trackbacks
 815                 if ( $wgUseTrackbacks ) {
 816                         $this->addTrackbacks();
 817                 }
 818
 819                 wfRunHooks( 'ArticleViewFooter', array( $this ) );
 820
 821         }
 822
 823         /**
 824          * If patrol is possible, output a patrol UI box. This is called from the
 825          * footer section of ordinary page views. If patrol is not possible or not
 826          * desired, does nothing.
 827          */
 828         public function showPatrolFooter() {
 829                 global $wgOut, $wgRequest, $wgUser;
 830
 831                 $rcid = $wgRequest->getVal( 'rcid' );
 832
 833                 if ( !$rcid || !$this->getTitle()->quickUserCan( 'patrol' ) ) {
 834                         return;
 835                 }
 836
 837                 $token = $wgUser->editToken( $rcid );
 838                 $wgOut->preventClickjacking();
 839
 840                 $wgOut->addHTML(
 841                         "<div class='patrollink'>" .
 842                                 wfMsgHtml(
 843                                         'markaspatrolledlink',
 844                                         Linker::link(
 845                                                 $this->getTitle(),
 846                                                 wfMsgHtml( 'markaspatrolledtext' ),
 847                                                 array(),
 848                                                 array(
 849                                                         'action' => 'markpatrolled',
 850                                                         'rcid' => $rcid,
 851                                                         'token' => $token,
 852                                                 ),
 853                                                 array( 'known', 'noclasses' )
 854                                         )
 855                                 ) .
 856                         '</div>'
 857                 );
 858         }
 859
 860         /**
 861          * Show the error text for a missing article. For articles in the MediaWiki
 862          * namespace, show the default message text. To be called from Article::view().
 863          */
 864         public function showMissingArticle() {
 865                 global $wgOut, $wgRequest, $wgUser;
 866
 867                 # Show info in user (talk) namespace. Does the user exist? Is he blocked?
 868                 if ( $this->getTitle()->getNamespace() == NS_USER || $this->getTitle()->getNamespace() == NS_USER_TALK ) {
 869                         $parts = explode( '/', $this->getTitle()->getText() );
 870                         $rootPart = $parts[0];
 871                         $user = User::newFromName( $rootPart, false /* allow IP users*/ );
 872                         $ip = User::isIP( $rootPart );
 873
 874                         if ( !$user->isLoggedIn() && !$ip ) { # User does not exist
 875                                 $wgOut->wrapWikiMsg( "<div class=\"mw-userpage-userdoesnotexist error\">\n\$1\n</div>",
 876                                         array( 'userpage-userdoesnotexist-view', wfEscapeWikiText( $rootPart ) ) );
 877                         } elseif ( $user->isBlocked() ) { # Show log extract if the user is currently blocked
 878                                 LogEventsList::showLogExtract(
 879                                         $wgOut,
 880                                         'block',
 881                                         $user->getUserPage()->getPrefixedText(),
 882                                         '',
 883                                         array(
 884                                                 'lim' => 1,
 885                                                 'showIfEmpty' => false,
 886                                                 'msgKey' => array(
 887                                                         'blocked-notice-logextract',
 888                                                         $user->getName() # Support GENDER in notice
 889                                                 )
 890                                         )
 891                                 );
 892                         }
 893                 }
 894
 895                 wfRunHooks( 'ShowMissingArticle', array( $this ) );
 896
 897                 # Show delete and move logs
 898                 LogEventsList::showLogExtract( $wgOut, array( 'delete', 'move' ), $this->getTitle()->getPrefixedText(), '',
 899                         array(  'lim' => 10,
 900                                 'conds' => array( "log_action != 'revision'" ),
 901                                 'showIfEmpty' => false,
 902                                 'msgKey' => array( 'moveddeleted-notice' ) )
 903                 );
 904
 905                 # Show error message
 906                 $oldid = $this->getOldID();
 907                 if ( $oldid ) {
 908                         $text = wfMsgNoTrans( 'missing-article',
 909                                 $this->getTitle()->getPrefixedText(),
 910                                 wfMsgNoTrans( 'missingarticle-rev', $oldid ) );
 911                 } elseif ( $this->getTitle()->getNamespace() === NS_MEDIAWIKI ) {
 912                         // Use the default message text
 913                         $text = $this->getTitle()->getDefaultMessageText();
 914                 } else {
 915                         $createErrors = $this->getTitle()->getUserPermissionsErrors( 'create', $wgUser );
 916                         $editErrors = $this->getTitle()->getUserPermissionsErrors( 'edit', $wgUser );
 917                         $errors = array_merge( $createErrors, $editErrors );
 918
 919                         if ( !count( $errors ) ) {
 920                                 $text = wfMsgNoTrans( 'noarticletext' );
 921                         } else {
 922                                 $text = wfMsgNoTrans( 'noarticletext-nopermission' );
 923                         }
 924                 }
 925                 $text = "<div class='noarticletext'>\n$text\n</div>";
 926
 927                 if ( !$this->mPage->hasViewableContent() ) {
 928                         // If there's no backing content, send a 404 Not Found
 929                         // for better machine handling of broken links.
 930                         $wgRequest->response()->header( "HTTP/1.1 404 Not Found" );
 931                 }
 932
 933                 $wgOut->addWikiText( $text );
 934         }
 935
 936         /**
 937          * If the revision requested for view is deleted, check permissions.
 938          * Send either an error message or a warning header to $wgOut.
 939          *
 940          * @return boolean true if the view is allowed, false if not.
 941          */
 942         public function showDeletedRevisionHeader() {
 943                 global $wgOut, $wgRequest;
 944
 945                 if ( !$this->mRevision->isDeleted( Revision::DELETED_TEXT ) ) {
 946                         // Not deleted
 947                         return true;
 948                 }
 949
 950                 // If the user is not allowed to see it...
 951                 if ( !$this->mRevision->userCan( Revision::DELETED_TEXT ) ) {
 952                         $wgOut->wrapWikiMsg( "<div class='mw-warning plainlinks'>\n$1\n</div>\n",
 953                                 'rev-deleted-text-permission' );
 954
 955                         return false;
 956                 // If the user needs to confirm that they want to see it...
 957                 } elseif ( $wgRequest->getInt( 'unhide' ) != 1 ) {
 958                         # Give explanation and add a link to view the revision...
 959                         $oldid = intval( $this->getOldID() );
 960                         $link = $this->getTitle()->getFullUrl( "oldid={$oldid}&unhide=1" );
 961                         $msg = $this->mRevision->isDeleted( Revision::DELETED_RESTRICTED ) ?
 962                                 'rev-suppressed-text-unhide' : 'rev-deleted-text-unhide';
 963                         $wgOut->wrapWikiMsg( "<div class='mw-warning plainlinks'>\n$1\n</div>\n",
 964                                 array( $msg, $link ) );
 965
 966                         return false;
 967                 // We are allowed to see...
 968                 } else {
 969                         $msg = $this->mRevision->isDeleted( Revision::DELETED_RESTRICTED ) ?
 970                                 'rev-suppressed-text-view' : 'rev-deleted-text-view';
 971                         $wgOut->wrapWikiMsg( "<div class='mw-warning plainlinks'>\n$1\n</div>\n", $msg );
 972
 973                         return true;
 974                 }
 975         }
 976
 977         /**
 978          * Execute the uncached parse for action=view
 979          */
 980         public function doViewParse() {
 981                 global $wgOut;
 982
 983                 $oldid = $this->getOldID();
 984                 $parserOptions = $this->mPage->getParserOptions();
 985
 986                 # Render printable version, use printable version cache
 987                 $parserOptions->setIsPrintable( $wgOut->isPrintable() );
 988
 989                 # Don't show section-edit links on old revisions... this way lies madness.
 990                 if ( !$this->isCurrent() || $wgOut->isPrintable() || !$this->getTitle()->quickUserCan( 'edit' ) ) {
 991                         $parserOptions->setEditSection( false );
 992                 }
 993
 994                 $useParserCache = $this->useParserCache( $oldid );
 995                 $this->outputWikiText( $this->getContent(), $useParserCache, $parserOptions );
 996
 997                 return true;
 998         }
 999
1000         /**
1001          * Try to fetch an expired entry from the parser cache. If it is present,
1002          * output it and return true. If it is not present, output nothing and
1003          * return false. This is used as a callback function for
1004          * PoolCounter::executeProtected().
1005          *
1006          * @return boolean
1007          */
1008         public function tryDirtyCache() {
1009                 global $wgOut;
1010                 $parserCache = ParserCache::singleton();
1011                 $options = $this->mPage->getParserOptions();
1012
1013                 if ( $wgOut->isPrintable() ) {
1014                         $options->setIsPrintable( true );
1015                         $options->setEditSection( false );
1016                 }
1017
1018                 $output = $parserCache->getDirty( $this, $options );
1019
1020                 if ( $output ) {
1021                         wfDebug( __METHOD__ . ": sending dirty output\n" );
1022                         wfDebugLog( 'dirty', "dirty output " . $parserCache->getKey( $this, $options ) . "\n" );
1023                         $wgOut->setSquidMaxage( 0 );
1024                         $this->mParserOutput = $output;
1025                         $wgOut->addParserOutput( $output );
1026                         $wgOut->addHTML( "<!-- parser cache is expired, sending anyway due to pool overload-->\n" );
1027
1028                         return true;
1029                 } else {
1030                         wfDebugLog( 'dirty', "dirty missing\n" );
1031                         wfDebug( __METHOD__ . ": no dirty cache\n" );
1032
1033                         return false;
1034                 }
1035         }
1036
1037         /**
1038          * View redirect
1039          *
1040          * @param $target Title|Array of destination(s) to redirect
1041          * @param $appendSubtitle Boolean [optional]
1042          * @param $forceKnown Boolean: should the image be shown as a bluelink regardless of existence?
1043          * @return string containing HMTL with redirect link
1044          */
1045         public function viewRedirect( $target, $appendSubtitle = true, $forceKnown = false ) {
1046                 global $wgOut, $wgLang, $wgStylePath;
1047
1048                 if ( !is_array( $target ) ) {
1049                         $target = array( $target );
1050                 }
1051
1052                 $imageDir = $wgLang->getDir();
1053
1054                 if ( $appendSubtitle ) {
1055                         $wgOut->appendSubtitle( wfMsgHtml( 'redirectpagesub' ) );
1056                 }
1057
1058                 // the loop prepends the arrow image before the link, so the first case needs to be outside
1059                 $title = array_shift( $target );
1060
1061                 if ( $forceKnown ) {
1062                         $link = Linker::linkKnown( $title, htmlspecialchars( $title->getFullText() ) );
1063                 } else {
1064                         $link = Linker::link( $title, htmlspecialchars( $title->getFullText() ) );
1065                 }
1066
1067                 $nextRedirect = $wgStylePath . '/common/images/nextredirect' . $imageDir . '.png';
1068                 $alt = $wgLang->isRTL() ? '←' : '→';
1069                 // Automatically append redirect=no to each link, since most of them are redirect pages themselves.
1070                 foreach ( $target as $rt ) {
1071                         $link .= Html::element( 'img', array( 'src' => $nextRedirect, 'alt' => $alt ) );
1072                         if ( $forceKnown ) {
1073                                 $link .= Linker::linkKnown( $rt, htmlspecialchars( $rt->getFullText(), array(), array( 'redirect' => 'no' ) ) );
1074                         } else {
1075                                 $link .= Linker::link( $rt, htmlspecialchars( $rt->getFullText() ), array(), array( 'redirect' => 'no' ) );
1076                         }
1077                 }
1078
1079                 $imageUrl = $wgStylePath . '/common/images/redirect' . $imageDir . '.png';
1080                 return '<div class="redirectMsg">' .
1081                         Html::element( 'img', array( 'src' => $imageUrl, 'alt' => '#REDIRECT' ) ) .
1082                         '<span class="redirectText">' . $link . '</span></div>';
1083         }
1084
1085         /**
1086          * Builds trackback links for article display if $wgUseTrackbacks is set to true
1087          */
1088         public function addTrackbacks() {
1089                 global $wgOut;
1090
1091                 $dbr = wfGetDB( DB_SLAVE );
1092                 $tbs = $dbr->select( 'trackbacks',
1093                         array( 'tb_id', 'tb_title', 'tb_url', 'tb_ex', 'tb_name' ),
1094                         array( 'tb_page' => $this->mPage->getID() )
1095                 );
1096
1097                 if ( !$dbr->numRows( $tbs ) ) {
1098                         return;
1099                 }
1100
1101                 $wgOut->preventClickjacking();
1102
1103                 $tbtext = "";
1104                 foreach ( $tbs as $o ) {
1105                         $rmvtxt = "";
1106
1107                         if ( $this->getContext()->getUser()->isAllowed( 'trackback' ) ) {
1108                                 $delurl = $this->getTitle()->getFullURL( "action=deletetrackback&tbid=" .
1109                                         $o->tb_id . "&token=" . urlencode( $this->getContext()->getUser()->editToken() ) );
1110                                 $rmvtxt = wfMsg( 'trackbackremove', htmlspecialchars( $delurl ) );
1111                         }
1112
1113                         $tbtext .= "\n";
1114                         $tbtext .= wfMsgNoTrans( strlen( $o->tb_ex ) ? 'trackbackexcerpt' : 'trackback',
1115                                         $o->tb_title,
1116                                         $o->tb_url,
1117                                         $o->tb_ex,
1118                                         $o->tb_name,
1119                                         $rmvtxt );
1120                 }
1121
1122                 $wgOut->wrapWikiMsg( "<div id='mw_trackbacks'>\n$1\n</div>\n", array( 'trackbackbox', $tbtext ) );
1123         }
1124
1125         /**
1126          * Removes trackback record for current article from trackbacks table
1127          * @deprecated since 1.19
1128          */
1129         public function deletetrackback() {
1130                 return Action::factory( 'deletetrackback', $this )->show();
1131         }
1132
1133         /**
1134          * Handle action=render
1135          */
1136
1137         public function render() {
1138                 global $wgOut;
1139
1140                 $wgOut->setArticleBodyOnly( true );
1141                 $this->view();
1142         }
1143
1144         /**
1145          * Handle action=purge
1146          */
1147         public function purge() {
1148                 return Action::factory( 'purge', $this )->show();
1149         }
1150
1151         /**
1152          * Mark this particular edit/page as patrolled
1153          * @deprecated since 1.19
1154          */
1155         public function markpatrolled() {
1156                 Action::factory( 'markpatrolled', $this )->show();
1157         }
1158
1159         /**
1160          * User-interface handler for the "watch" action.
1161          * Requires Request to pass a token as of 1.19.
1162          * @deprecated since 1.18
1163          */
1164         public function watch() {
1165                 Action::factory( 'watch', $this )->show();
1166         }
1167
1168         /**
1169          * Add this page to $wgUser's watchlist
1170          *
1171          * This is safe to be called multiple times
1172          *
1173          * @return bool true on successful watch operation
1174          * @deprecated since 1.18
1175          */
1176         public function doWatch() {
1177                 global $wgUser;
1178                 return WatchAction::doWatch( $this->getTitle(), $wgUser );
1179         }
1180
1181         /**
1182          * User interface handler for the "unwatch" action.
1183          * Requires Request to pass a token as of 1.19.
1184          * @deprecated since 1.18
1185          */
1186         public function unwatch() {
1187                 Action::factory( 'unwatch', $this )->show();
1188         }
1189
1190         /**
1191          * Stop watching a page
1192          * @return bool true on successful unwatch
1193          * @deprecated since 1.18
1194          */
1195         public function doUnwatch() {
1196                 global $wgUser;
1197                 return WatchAction::doUnwatch( $this->getTitle(), $wgUser );
1198         }
1199
1200         /**
1201          * action=protect handler
1202          */
1203         public function protect() {
1204                 $form = new ProtectionForm( $this );
1205                 $form->execute();
1206         }
1207
1208         /**
1209          * action=unprotect handler (alias)
1210          */
1211         public function unprotect() {
1212                 $this->protect();
1213         }
1214
1215         /**
1216          * Info about this page
1217          * Called for ?action=info when $wgAllowPageInfo is on.
1218          */
1219         public function info() {
1220                 Action::factory( 'info', $this )->show();
1221         }
1222
1223         /**
1224          * Overriden by ImagePage class, only present here to avoid a fatal error
1225          * Called for ?action=revert
1226          */
1227         public function revert() {
1228                 Action::factory( 'revert', $this )->show();
1229         }
1230
1231         /**
1232          * User interface for rollback operations
1233          */
1234         public function rollback() {
1235                 Action::factory( 'rollback', $this )->show();
1236         }
1237
1238         /**
1239          * Output a redirect back to the article.
1240          * This is typically used after an edit.
1241          *
1242          * @deprecated in 1.19; call $wgOut->redirect() directly
1243          * @param $noRedir Boolean: add redirect=no
1244          * @param $sectionAnchor String: section to redirect to, including "#"
1245          * @param $extraQuery String: extra query params
1246          */
1247         public function doRedirect( $noRedir = false, $sectionAnchor = '', $extraQuery = '' ) {
1248                 wfDeprecated( __METHOD__ );
1249                 global $wgOut;
1250
1251                 if ( $noRedir ) {
1252                         $query = 'redirect=no';
1253                         if ( $extraQuery )
1254                                 $query .= "&$extraQuery";
1255                 } else {
1256                         $query = $extraQuery;
1257                 }
1258
1259                 $wgOut->redirect( $this->getTitle()->getFullURL( $query ) . $sectionAnchor );
1260         }
1261
1262         /**
1263          * Auto-generates a deletion reason
1264          *
1265          * @param &$hasHistory Boolean: whether the page has a history
1266          * @return mixed String containing deletion reason or empty string, or boolean false
1267          *    if no revision occurred
1268          */
1269         public function generateReason( &$hasHistory ) {
1270                 global $wgContLang;
1271
1272                 $dbw = wfGetDB( DB_MASTER );
1273                 // Get the last revision
1274                 $rev = Revision::newFromTitle( $this->getTitle() );
1275
1276                 if ( is_null( $rev ) ) {
1277                         return false;
1278                 }
1279
1280                 // Get the article's contents
1281                 $contents = $rev->getText();
1282                 $blank = false;
1283
1284                 // If the page is blank, use the text from the previous revision,
1285                 // which can only be blank if there's a move/import/protect dummy revision involved
1286                 if ( $contents == '' ) {
1287                         $prev = $rev->getPrevious();
1288
1289                         if ( $prev )    {
1290                                 $contents = $prev->getText();
1291                                 $blank = true;
1292                         }
1293                 }
1294
1295                 // Find out if there was only one contributor
1296                 // Only scan the last 20 revisions
1297                 $res = $dbw->select( 'revision', 'rev_user_text',
1298                         array( 'rev_page' => $this->mPage->getID(), $dbw->bitAnd( 'rev_deleted', Revision::DELETED_USER ) . ' = 0' ),
1299                         __METHOD__,
1300                         array( 'LIMIT' => 20 )
1301                 );
1302
1303                 if ( $res === false ) {
1304                         // This page has no revisions, which is very weird
1305                         return false;
1306                 }
1307
1308                 $hasHistory = ( $res->numRows() > 1 );
1309                 $row = $dbw->fetchObject( $res );
1310
1311                 if ( $row ) { // $row is false if the only contributor is hidden
1312                         $onlyAuthor = $row->rev_user_text;
1313                         // Try to find a second contributor
1314                         foreach ( $res as $row ) {
1315                                 if ( $row->rev_user_text != $onlyAuthor ) { // Bug 22999
1316                                         $onlyAuthor = false;
1317                                         break;
1318                                 }
1319                         }
1320                 } else {
1321                         $onlyAuthor = false;
1322                 }
1323
1324                 // Generate the summary with a '$1' placeholder
1325                 if ( $blank ) {
1326                         // The current revision is blank and the one before is also
1327                         // blank. It's just not our lucky day
1328                         $reason = wfMsgForContent( 'exbeforeblank', '$1' );
1329                 } else {
1330                         if ( $onlyAuthor ) {
1331                                 $reason = wfMsgForContent( 'excontentauthor', '$1', $onlyAuthor );
1332                         } else {
1333                                 $reason = wfMsgForContent( 'excontent', '$1' );
1334                         }
1335                 }
1336
1337                 if ( $reason == '-' ) {
1338                         // Allow these UI messages to be blanked out cleanly
1339                         return '';
1340                 }
1341
1342                 // Replace newlines with spaces to prevent uglyness
1343                 $contents = preg_replace( "/[\n\r]/", ' ', $contents );
1344                 // Calculate the maximum amount of chars to get
1345                 // Max content length = max comment length - length of the comment (excl. $1)
1346                 $maxLength = 255 - ( strlen( $reason ) - 2 );
1347                 $contents = $wgContLang->truncate( $contents, $maxLength );
1348                 // Remove possible unfinished links
1349                 $contents = preg_replace( '/\[\[([^\]]*)\]?$/', '$1', $contents );
1350                 // Now replace the '$1' placeholder
1351                 $reason = str_replace( '$1', $contents, $reason );
1352
1353                 return $reason;
1354         }
1355
1356
1357         /**
1358          * UI entry point for page deletion
1359          */
1360         public function delete() {
1361                 global $wgOut, $wgRequest;
1362
1363                 $confirm = $wgRequest->wasPosted() &&
1364                                 $this->getContext()->getUser()->matchEditToken( $wgRequest->getVal( 'wpEditToken' ) );
1365
1366                 $this->DeleteReasonList = $wgRequest->getText( 'wpDeleteReasonList', 'other' );
1367                 $this->DeleteReason = $wgRequest->getText( 'wpReason' );
1368
1369                 $reason = $this->DeleteReasonList;
1370
1371                 if ( $reason != 'other' && $this->DeleteReason != '' ) {
1372                         // Entry from drop down menu + additional comment
1373                         $reason .= wfMsgForContent( 'colon-separator' ) . $this->DeleteReason;
1374                 } elseif ( $reason == 'other' ) {
1375                         $reason = $this->DeleteReason;
1376                 }
1377
1378                 # Flag to hide all contents of the archived revisions
1379                 $suppress = $wgRequest->getVal( 'wpSuppress' ) && $this->getContext()->getUser()->isAllowed( 'suppressrevision' );
1380
1381                 # This code desperately needs to be totally rewritten
1382
1383                 # Read-only check...
1384                 if ( wfReadOnly() ) {
1385                         $wgOut->readOnlyPage();
1386
1387                         return;
1388                 }
1389
1390                 # Check permissions
1391                 $permission_errors = $this->getTitle()->getUserPermissionsErrors( 'delete', $this->getContext()->getUser() );
1392
1393                 if ( count( $permission_errors ) > 0 ) {
1394                         $wgOut->showPermissionsErrorPage( $permission_errors );
1395
1396                         return;
1397                 }
1398
1399                 $wgOut->setPagetitle( wfMsg( 'delete-confirm', $this->getTitle()->getPrefixedText() ) );
1400
1401                 # Better double-check that it hasn't been deleted yet!
1402                 $dbw = wfGetDB( DB_MASTER );
1403                 $conds = $this->getTitle()->pageCond();
1404                 $latest = $dbw->selectField( 'page', 'page_latest', $conds, __METHOD__ );
1405                 if ( $latest === false ) {
1406                         $wgOut->showFatalError(
1407                                 Html::rawElement(
1408                                         'div',
1409                                         array( 'class' => 'error mw-error-cannotdelete' ),
1410                                         wfMsgExt( 'cannotdelete', array( 'parse' ),
1411                                                 wfEscapeWikiText( $this->getTitle()->getPrefixedText() ) )
1412                                 )
1413                         );
1414                         $wgOut->addHTML( Xml::element( 'h2', null, LogPage::logName( 'delete' ) ) );
1415                         LogEventsList::showLogExtract(
1416                                 $wgOut,
1417                                 'delete',
1418                                 $this->getTitle()->getPrefixedText()
1419                         );
1420
1421                         return;
1422                 }
1423
1424                 # Hack for big sites
1425                 $bigHistory = $this->mPage->isBigDeletion();
1426                 if ( $bigHistory && !$this->getTitle()->userCan( 'bigdelete' ) ) {
1427                         global $wgLang, $wgDeleteRevisionsLimit;
1428
1429                         $wgOut->wrapWikiMsg( "<div class='error'>\n$1\n</div>\n",
1430                                 array( 'delete-toobig', $wgLang->formatNum( $wgDeleteRevisionsLimit ) ) );
1431
1432                         return;
1433                 }
1434
1435                 if ( $confirm ) {
1436                         $this->doDelete( $reason, $suppress );
1437
1438                         if ( $wgRequest->getCheck( 'wpWatch' ) && $this->getContext()->getUser()->isLoggedIn() ) {
1439                                 $this->doWatch();
1440                         } elseif ( $this->getTitle()->userIsWatching() ) {
1441                                 $this->doUnwatch();
1442                         }
1443
1444                         return;
1445                 }
1446
1447                 // Generate deletion reason
1448                 $hasHistory = false;
1449                 if ( !$reason ) {
1450                         $reason = $this->generateReason( $hasHistory );
1451                 }
1452
1453                 // If the page has a history, insert a warning
1454                 if ( $hasHistory && !$confirm ) {
1455                         global $wgLang;
1456
1457                         $revisions = $this->mPage->estimateRevisionCount();
1458                         // @todo FIXME: i18n issue/patchwork message
1459                         $wgOut->addHTML( '<strong class="mw-delete-warning-revisions">' .
1460                                 wfMsgExt( 'historywarning', array( 'parseinline' ), $wgLang->formatNum( $revisions ) ) .
1461                                 wfMsgHtml( 'word-separator' ) . Linker::link( $this->getTitle(),
1462                                         wfMsgHtml( 'history' ),
1463                                         array( 'rel' => 'archives' ),
1464                                         array( 'action' => 'history' ) ) .
1465                                 '</strong>'
1466                         );
1467
1468                         if ( $bigHistory ) {
1469                                 global $wgDeleteRevisionsLimit;
1470                                 $wgOut->wrapWikiMsg( "<div class='error'>\n$1\n</div>\n",
1471                                         array( 'delete-warning-toobig', $wgLang->formatNum( $wgDeleteRevisionsLimit ) ) );
1472                         }
1473                 }
1474
1475                 return $this->confirmDelete( $reason );
1476         }
1477
1478         /**
1479          * Output deletion confirmation dialog
1480          * @todo FIXME: Move to another file?
1481          * @param $reason String: prefilled reason
1482          */
1483         public function confirmDelete( $reason ) {
1484                 global $wgOut;
1485
1486                 wfDebug( "Article::confirmDelete\n" );
1487
1488                 $deleteBackLink = Linker::linkKnown( $this->getTitle() );
1489                 $wgOut->setSubtitle( wfMsgHtml( 'delete-backlink', $deleteBackLink ) );
1490                 $wgOut->setRobotPolicy( 'noindex,nofollow' );
1491                 $wgOut->addWikiMsg( 'confirmdeletetext' );
1492
1493                 wfRunHooks( 'ArticleConfirmDelete', array( $this, $wgOut, &$reason ) );
1494
1495                 if ( $this->getContext()->getUser()->isAllowed( 'suppressrevision' ) ) {
1496                         $suppress = "<tr id=\"wpDeleteSuppressRow\">
1497                                         <td></td>
1498                                         <td class='mw-input'><strong>" .
1499                                                 Xml::checkLabel( wfMsg( 'revdelete-suppress' ),
1500                                                         'wpSuppress', 'wpSuppress', false, array( 'tabindex' => '4' ) ) .
1501                                         "</strong></td>
1502                                 </tr>";
1503                 } else {
1504                         $suppress = '';
1505                 }
1506                 $checkWatch = $this->getContext()->getUser()->getBoolOption( 'watchdeletion' ) || $this->getTitle()->userIsWatching();
1507
1508                 $form = Xml::openElement( 'form', array( 'method' => 'post',
1509                         'action' => $this->getTitle()->getLocalURL( 'action=delete' ), 'id' => 'deleteconfirm' ) ) .
1510                         Xml::openElement( 'fieldset', array( 'id' => 'mw-delete-table' ) ) .
1511                         Xml::tags( 'legend', null, wfMsgExt( 'delete-legend', array( 'parsemag', 'escapenoentities' ) ) ) .
1512                         Xml::openElement( 'table', array( 'id' => 'mw-deleteconfirm-table' ) ) .
1513                         "<tr id=\"wpDeleteReasonListRow\">
1514                                 <td class='mw-label'>" .
1515                                         Xml::label( wfMsg( 'deletecomment' ), 'wpDeleteReasonList' ) .
1516                                 "</td>
1517                                 <td class='mw-input'>" .
1518                                         Xml::listDropDown( 'wpDeleteReasonList',
1519                                                 wfMsgForContent( 'deletereason-dropdown' ),
1520                                                 wfMsgForContent( 'deletereasonotherlist' ), '', 'wpReasonDropDown', 1 ) .
1521                                 "</td>
1522                         </tr>
1523                         <tr id=\"wpDeleteReasonRow\">
1524                                 <td class='mw-label'>" .
1525                                         Xml::label( wfMsg( 'deleteotherreason' ), 'wpReason' ) .
1526                                 "</td>
1527                                 <td class='mw-input'>" .
1528                                 Html::input( 'wpReason', $reason, 'text', array(
1529                                         'size' => '60',
1530                                         'maxlength' => '255',
1531                                         'tabindex' => '2',
1532                                         'id' => 'wpReason',
1533                                         'autofocus'
1534                                 ) ) .
1535                                 "</td>
1536                         </tr>";
1537
1538                 # Disallow watching if user is not logged in
1539                 if ( $this->getContext()->getUser()->isLoggedIn() ) {
1540                         $form .= "
1541                         <tr>
1542                                 <td></td>
1543                                 <td class='mw-input'>" .
1544                                         Xml::checkLabel( wfMsg( 'watchthis' ),
1545                                                 'wpWatch', 'wpWatch', $checkWatch, array( 'tabindex' => '3' ) ) .
1546                                 "</td>
1547                         </tr>";
1548                 }
1549
1550                 $form .= "
1551                         $suppress
1552                         <tr>
1553                                 <td></td>
1554                                 <td class='mw-submit'>" .
1555                                         Xml::submitButton( wfMsg( 'deletepage' ),
1556                                                 array( 'name' => 'wpConfirmB', 'id' => 'wpConfirmB', 'tabindex' => '5' ) ) .
1557                                 "</td>
1558                         </tr>" .
1559                         Xml::closeElement( 'table' ) .
1560                         Xml::closeElement( 'fieldset' ) .
1561                         Html::hidden( 'wpEditToken', $this->getContext()->getUser()->editToken() ) .
1562                         Xml::closeElement( 'form' );
1563
1564                         if ( $this->getContext()->getUser()->isAllowed( 'editinterface' ) ) {
1565                                 $title = Title::makeTitle( NS_MEDIAWIKI, 'Deletereason-dropdown' );
1566                                 $link = Linker::link(
1567                                         $title,
1568                                         wfMsgHtml( 'delete-edit-reasonlist' ),
1569                                         array(),
1570                                         array( 'action' => 'edit' )
1571                                 );
1572                                 $form .= '<p class="mw-delete-editreasons">' . $link . '</p>';
1573                         }
1574
1575                 $wgOut->addHTML( $form );
1576                 $wgOut->addHTML( Xml::element( 'h2', null, LogPage::logName( 'delete' ) ) );
1577                 LogEventsList::showLogExtract( $wgOut, 'delete',
1578                         $this->getTitle()->getPrefixedText()
1579                 );
1580         }
1581
1582         /**
1583          * Perform a deletion and output success or failure messages
1584          */
1585         public function doDelete( $reason, $suppress = false ) {
1586                 global $wgOut;
1587
1588                 $id = $this->getTitle()->getArticleID( Title::GAID_FOR_UPDATE );
1589
1590                 $error = '';
1591                 if ( $this->mPage->doDeleteArticle( $reason, $suppress, $id, $error ) ) {
1592                         $deleted = $this->getTitle()->getPrefixedText();
1593
1594                         $wgOut->setPagetitle( wfMsg( 'actioncomplete' ) );
1595                         $wgOut->setRobotPolicy( 'noindex,nofollow' );
1596
1597                         $loglink = '[[Special:Log/delete|' . wfMsgNoTrans( 'deletionlog' ) . ']]';
1598
1599                         $wgOut->addWikiMsg( 'deletedtext', wfEscapeWikiText( $deleted ), $loglink );
1600                         $wgOut->returnToMain( false );
1601                 } else {
1602                         if ( $error == '' ) {
1603                                 $wgOut->showFatalError(
1604                                         Html::rawElement(
1605                                                 'div',
1606                                                 array( 'class' => 'error mw-error-cannotdelete' ),
1607                                                 wfMsgExt( 'cannotdelete', array( 'parse' ),
1608                                                         wfEscapeWikiText( $this->getTitle()->getPrefixedText() ) )
1609                                         )
1610                                 );
1611
1612                                 $wgOut->addHTML( Xml::element( 'h2', null, LogPage::logName( 'delete' ) ) );
1613
1614                                 LogEventsList::showLogExtract(
1615                                         $wgOut,
1616                                         'delete',
1617                                         $this->getTitle()->getPrefixedText()
1618                                 );
1619                         } else {
1620                                 $wgOut->showFatalError( $error );
1621                         }
1622                 }
1623         }
1624
1625         /**
1626          * Generate the navigation links when browsing through an article revisions
1627          * It shows the information as:
1628          *   Revision as of \<date\>; view current revision
1629          *   \<- Previous version | Next Version -\>
1630          *
1631          * @param $oldid String: revision ID of this article revision
1632          */
1633         public function setOldSubtitle( $oldid = 0 ) {
1634                 global $wgLang, $wgOut, $wgUser, $wgRequest;
1635
1636                 if ( !wfRunHooks( 'DisplayOldSubtitle', array( &$this, &$oldid ) ) ) {
1637                         return;
1638                 }
1639
1640                 $unhide = $wgRequest->getInt( 'unhide' ) == 1;
1641
1642                 # Cascade unhide param in links for easy deletion browsing
1643                 $extraParams = array();
1644                 if ( $wgRequest->getVal( 'unhide' ) ) {
1645                         $extraParams['unhide'] = 1;
1646                 }
1647
1648                 $revision = Revision::newFromId( $oldid );
1649                 $timestamp = $revision->getTimestamp();
1650
1651                 $current = ( $oldid == $this->mPage->getLatest() );
1652                 $td = $wgLang->timeanddate( $timestamp, true );
1653                 $tddate = $wgLang->date( $timestamp, true );
1654                 $tdtime = $wgLang->time( $timestamp, true );
1655
1656                 $lnk = $current
1657                         ? wfMsgHtml( 'currentrevisionlink' )
1658                         : Linker::link(
1659                                 $this->getTitle(),
1660                                 wfMsgHtml( 'currentrevisionlink' ),
1661                                 array(),
1662                                 $extraParams,
1663                                 array( 'known', 'noclasses' )
1664                         );
1665                 $curdiff = $current
1666                         ? wfMsgHtml( 'diff' )
1667                         : Linker::link(
1668                                 $this->getTitle(),
1669                                 wfMsgHtml( 'diff' ),
1670                                 array(),
1671                                 array(
1672                                         'diff' => 'cur',
1673                                         'oldid' => $oldid
1674                                 ) + $extraParams,
1675                                 array( 'known', 'noclasses' )
1676                         );
1677                 $prev = $this->getTitle()->getPreviousRevisionID( $oldid ) ;
1678                 $prevlink = $prev
1679                         ? Linker::link(
1680                                 $this->getTitle(),
1681                                 wfMsgHtml( 'previousrevision' ),
1682                                 array(),
1683                                 array(
1684                                         'direction' => 'prev',
1685                                         'oldid' => $oldid
1686                                 ) + $extraParams,
1687                                 array( 'known', 'noclasses' )
1688                         )
1689                         : wfMsgHtml( 'previousrevision' );
1690                 $prevdiff = $prev
1691                         ? Linker::link(
1692                                 $this->getTitle(),
1693                                 wfMsgHtml( 'diff' ),
1694                                 array(),
1695                                 array(
1696                                         'diff' => 'prev',
1697                                         'oldid' => $oldid
1698                                 ) + $extraParams,
1699                                 array( 'known', 'noclasses' )
1700                         )
1701                         : wfMsgHtml( 'diff' );
1702                 $nextlink = $current
1703                         ? wfMsgHtml( 'nextrevision' )
1704                         : Linker::link(
1705                                 $this->getTitle(),
1706                                 wfMsgHtml( 'nextrevision' ),
1707                                 array(),
1708                                 array(
1709                                         'direction' => 'next',
1710                                         'oldid' => $oldid
1711                                 ) + $extraParams,
1712                                 array( 'known', 'noclasses' )
1713                         );
1714                 $nextdiff = $current
1715                         ? wfMsgHtml( 'diff' )
1716                         : Linker::link(
1717                                 $this->getTitle(),
1718                                 wfMsgHtml( 'diff' ),
1719                                 array(),
1720                                 array(
1721                                         'diff' => 'next',
1722                                         'oldid' => $oldid
1723                                 ) + $extraParams,
1724                                 array( 'known', 'noclasses' )
1725                         );
1726
1727                 $cdel = '';
1728
1729                 // User can delete revisions or view deleted revisions...
1730                 $canHide = $wgUser->isAllowed( 'deleterevision' );
1731                 if ( $canHide || ( $revision->getVisibility() && $wgUser->isAllowed( 'deletedhistory' ) ) ) {
1732                         if ( !$revision->userCan( Revision::DELETED_RESTRICTED ) ) {
1733                                 $cdel = Linker::revDeleteLinkDisabled( $canHide ); // rev was hidden from Sysops
1734                         } else {
1735                                 $query = array(
1736                                         'type'   => 'revision',
1737                                         'target' => $this->getTitle()->getPrefixedDbkey(),
1738                                         'ids'    => $oldid
1739                                 );
1740                                 $cdel = Linker::revDeleteLink( $query, $revision->isDeleted( File::DELETED_RESTRICTED ), $canHide );
1741                         }
1742                         $cdel .= ' ';
1743                 }
1744
1745                 # Show user links if allowed to see them. If hidden, then show them only if requested...
1746                 $userlinks = Linker::revUserTools( $revision, !$unhide );
1747
1748                 $infomsg = $current && !wfMessage( 'revision-info-current' )->isDisabled()
1749                         ? 'revision-info-current'
1750                         : 'revision-info';
1751
1752                 $r = "\n\t\t\t\t<div id=\"mw-{$infomsg}\">" .
1753                         wfMsgExt(
1754                                 $infomsg,
1755                                 array( 'parseinline', 'replaceafter' ),
1756                                 $td,
1757                                 $userlinks,
1758                                 $revision->getID(),
1759                                 $tddate,
1760                                 $tdtime,
1761                                 $revision->getUser()
1762                         ) .
1763                         "</div>\n" .
1764                         "\n\t\t\t\t<div id=\"mw-revision-nav\">" . $cdel . wfMsgExt( 'revision-nav', array( 'escapenoentities', 'parsemag', 'replaceafter' ),
1765                         $prevdiff, $prevlink, $lnk, $curdiff, $nextlink, $nextdiff ) . "</div>\n\t\t\t";
1766
1767                 $wgOut->setSubtitle( $r );
1768         }
1769
1770         /* Caching functions */
1771
1772         /**
1773          * checkLastModified returns true if it has taken care of all
1774          * output to the client that is necessary for this request.
1775          * (that is, it has sent a cached version of the page)
1776          *
1777          * @return boolean true if cached version send, false otherwise
1778          */
1779         protected function tryFileCache() {
1780                 static $called = false;
1781
1782                 if ( $called ) {
1783                         wfDebug( "Article::tryFileCache(): called twice!?\n" );
1784                         return false;
1785                 }
1786
1787                 $called = true;
1788                 if ( $this->isFileCacheable() ) {
1789                         $cache = new HTMLFileCache( $this->getTitle() );
1790                         if ( $cache->isFileCacheGood( $this->mPage->getTouched() ) ) {
1791                                 wfDebug( "Article::tryFileCache(): about to load file\n" );
1792                                 $cache->loadFromFileCache();
1793                                 return true;
1794                         } else {
1795                                 wfDebug( "Article::tryFileCache(): starting buffer\n" );
1796                                 ob_start( array( &$cache, 'saveToFileCache' ) );
1797                         }
1798                 } else {
1799                         wfDebug( "Article::tryFileCache(): not cacheable\n" );
1800                 }
1801
1802                 return false;
1803         }
1804
1805         /**
1806          * Check if the page can be cached
1807          * @return bool
1808          */
1809         public function isFileCacheable() {
1810                 $cacheable = false;
1811
1812                 if ( HTMLFileCache::useFileCache() ) {
1813                         $cacheable = $this->mPage->getID() && !$this->mRedirectedFrom && !$this->getTitle()->isRedirect();
1814                         // Extension may have reason to disable file caching on some pages.
1815                         if ( $cacheable ) {
1816                                 $cacheable = wfRunHooks( 'IsFileCacheable', array( &$this ) );
1817                         }
1818                 }
1819
1820                 return $cacheable;
1821         }
1822
1823         /**#@-*/
1824
1825         /**
1826          * Add the primary page-view wikitext to the output buffer
1827          * Saves the text into the parser cache if possible.
1828          * Updates templatelinks if it is out of date.
1829          *
1830          * @param $text String
1831          * @param $cache Boolean
1832          * @param $parserOptions mixed ParserOptions object, or boolean false
1833          */
1834         public function outputWikiText( $text, $cache = true, $parserOptions = false ) {
1835                 global $wgOut;
1836
1837                 $this->mParserOutput = $this->getOutputFromWikitext( $text, $cache, $parserOptions );
1838
1839                 $this->doCascadeProtectionUpdates( $this->mParserOutput );
1840
1841                 $wgOut->addParserOutput( $this->mParserOutput );
1842         }
1843
1844         /**
1845          * Lightweight method to get the parser output for a page, checking the parser cache
1846          * and so on. Doesn't consider most of the stuff that WikiPage::view is forced to
1847          * consider, so it's not appropriate to use there.
1848          *
1849          * @since 1.16 (r52326) for LiquidThreads
1850          *
1851          * @param $oldid mixed integer Revision ID or null
1852          * @param $user User The relevant user
1853          * @return ParserOutput or false if the given revsion ID is not found
1854          */
1855         public function getParserOutput( $oldid = null, User $user = null ) {
1856                 global $wgEnableParserCache, $wgUser;
1857                 $user = is_null( $user ) ? $wgUser : $user;
1858
1859                 // Should the parser cache be used?
1860                 $useParserCache = $wgEnableParserCache &&
1861                         $user->getStubThreshold() == 0 &&
1862                         $this->mPage->exists() &&
1863                         $oldid === null;
1864
1865                 wfDebug( __METHOD__ . ': using parser cache: ' . ( $useParserCache ? 'yes' : 'no' ) . "\n" );
1866
1867                 if ( $user->getStubThreshold() ) {
1868                         wfIncrStats( 'pcache_miss_stub' );
1869                 }
1870
1871                 if ( $useParserCache ) {
1872                         $parserOutput = ParserCache::singleton()->get( $this, $this->mPage->getParserOptions() );
1873                         if ( $parserOutput !== false ) {
1874                                 return $parserOutput;
1875                         }
1876                 }
1877
1878                 // Cache miss; parse and output it.
1879                 if ( $oldid === null ) {
1880                         $text = $this->mPage->getRawText();
1881                 } else {
1882                         $rev = Revision::newFromTitle( $this->getTitle(), $oldid );
1883                         if ( $rev === null ) {
1884                                 return false;
1885                         }
1886                         $text = $rev->getText();
1887                 }
1888
1889                 return $this->getOutputFromWikitext( $text, $useParserCache );
1890         }
1891
1892         /**
1893          * This does all the heavy lifting for outputWikitext, except it returns the parser
1894          * output instead of sending it straight to $wgOut. Makes things nice and simple for,
1895          * say, embedding thread pages within a discussion system (LiquidThreads)
1896          *
1897          * @param $text string
1898          * @param $cache boolean
1899          * @param $parserOptions parsing options, defaults to false
1900          * @return ParserOutput
1901          */
1902         public function getOutputFromWikitext( $text, $cache = true, $parserOptions = false ) {
1903                 global $wgParser, $wgEnableParserCache, $wgUseFileCache;
1904
1905                 if ( !$parserOptions ) {
1906                         $parserOptions = $this->mPage->getParserOptions();
1907                 }
1908
1909                 $time = - wfTime();
1910                 $this->mParserOutput = $wgParser->parse( $text, $this->getTitle(),
1911                         $parserOptions, true, true, $this->getRevIdFetched() );
1912                 $time += wfTime();
1913
1914                 # Timing hack
1915                 if ( $time > 3 ) {
1916                         wfDebugLog( 'slow-parse', sprintf( "%-5.2f %s", $time,
1917                                 $this->getTitle()->getPrefixedDBkey() ) );
1918                 }
1919
1920                 if ( $wgEnableParserCache && $cache && $this->mParserOutput->isCacheable() ) {
1921                         $parserCache = ParserCache::singleton();
1922                         $parserCache->save( $this->mParserOutput, $this, $parserOptions );
1923                 }
1924
1925                 // Make sure file cache is not used on uncacheable content.
1926                 // Output that has magic words in it can still use the parser cache
1927                 // (if enabled), though it will generally expire sooner.
1928                 if ( !$this->mParserOutput->isCacheable() || $this->mParserOutput->containsOldMagic() ) {
1929                         $wgUseFileCache = false;
1930                 }
1931
1932                 if ( $this->isCurrent() ) {
1933                         $this->mPage->doCascadeProtectionUpdates( $this->mParserOutput );
1934                 }
1935
1936                 return $this->mParserOutput;
1937         }
1938
1939         /**
1940          * Sets the context this Article is executed in
1941          *
1942          * @param $context RequestContext
1943          * @since 1.18
1944          */
1945         public function setContext( $context ) {
1946                 $this->mContext = $context;
1947         }
1948
1949         /**
1950          * Gets the context this Article is executed in
1951          *
1952          * @return RequestContext
1953          * @since 1.18
1954          */
1955         public function getContext() {
1956                 if ( $this->mContext instanceof RequestContext ) {
1957                         return $this->mContext;
1958                 } else {
1959                         wfDebug( __METHOD__ . " called and \$mContext is null. Return RequestContext::getMain(); for sanity\n" );
1960                         return RequestContext::getMain();
1961                 }
1962         }
1963
1964         /**
1965          * Use PHP's magic __get handler to handle accessing of
1966          * raw WikiPage fields for backwards compatibility.
1967          *
1968          * @param $fname String Field name
1969          */
1970         public function __get( $fname ) {
1971                 if ( property_exists( $this->mPage, $fname ) ) {
1972                         #wfWarn( "Access to raw $fname field " . __CLASS__ );
1973                         return $this->mPage->$fname;
1974                 }
1975         trigger_error( 'Inaccessible property via __get(): ' . $fname, E_USER_NOTICE );
1976         }
1977
1978         /**
1979          * Use PHP's magic __set handler to handle setting of
1980          * raw WikiPage fields for backwards compatibility.
1981          *
1982          * @param $fname String Field name
1983          * @param $fvalue mixed New value
1984          * @param $args Array Arguments to the method
1985          */
1986         public function __set( $fname, $fvalue ) {
1987                 if ( property_exists( $this->mPage, $fname ) ) {
1988                         #wfWarn( "Access to raw $fname field of " . __CLASS__ );
1989                         $this->mPage->$fname = $fvalue;
1990                 // Note: extensions may want to toss on new fields
1991                 } elseif ( !in_array( $fname, array( 'mContext', 'mPage' ) ) ) {
1992                         $this->mPage->$fname = $fvalue;
1993                 } else {
1994                         trigger_error( 'Inaccessible property via __get(): ' . $fname, E_USER_NOTICE );
1995                 }
1996         }
1997
1998         /**
1999          * Use PHP's magic __call handler to transform instance calls to
2000          * WikiPage functions for backwards compatibility.
2001          *
2002          * @param $fname String Name of called method
2003          * @param $args Array Arguments to the method
2004          */
2005         public function __call( $fname, $args ) {
2006                 if ( is_callable( array( $this->mPage, $fname ) ) ) {
2007                         #wfWarn( "Call to " . __CLASS__ . "::$fname; please use WikiPage instead" );
2008                         return call_user_func_array( array( $this->mPage, $fname ), $args );
2009                 }
2010         trigger_error( 'Inaccessible function via __call(): ' . $fname, E_USER_ERROR );
2011         }
2012
2013         // ****** B/C functions to work-around PHP silliness with __call and references ****** //
2014         public function updateRestrictions( $limit = array(), $reason = '', &$cascade = 0, $expiry = array() ) {
2015                 return $this->mPage->updateRestrictions( $limit, $reason, $cascade, $expiry );
2016         }
2017
2018         public function doDeleteArticle( $reason, $suppress = false, $id = 0, $commit = true, &$error = '' ) {
2019                 return $this->mPage->doDeleteArticle( $reason, $suppress, $id, $commit, $error );
2020         }
2021
2022         public function doRollback( $fromP, $summary, $token, $bot, &$resultDetails, User $user = null ) {
2023                 global $wgUser;
2024                 $user = is_null( $user ) ? $wgUser : $user;
2025                 return $this->mPage->doRollback( $fromP, $summary, $token, $bot, $resultDetails, $user );
2026         }
2027
2028         public function commitRollback( $fromP, $summary, $bot, &$resultDetails, User $guser = null ) {
2029                 global $wgUser;
2030                 $guser = is_null( $guser ) ? $wgUser : $guser;
2031                 return $this->mPage->commitRollback( $fromP, $summary, $bot, $resultDetails, $guser );
2032         }
2033
2034         // ****** B/C functions for static methods ( __callStatic is PHP>=5.3 ) ****** //
2035         public static function selectFields() {
2036                 return WikiPage::selectFields();
2037         }
2038
2039         public static function onArticleCreate( $title ) {
2040                 return WikiPage::onArticleCreate( $title );
2041         }
2042
2043         public static function onArticleDelete( $title ) {
2044                 return WikiPage::onArticleDelete( $title );
2045         }
2046
2047         public static function onArticleEdit( $title ) {
2048                 return WikiPage::onArticleEdit( $title );
2049         }
2050
2051         public static function getAutosummary( $oldtext, $newtext, $flags ) {
2052                 return WikiPage::getAutosummary( $oldtext, $newtext, $flags );
2053         }
2054         // ******
2055 }
2056
2057 class PoolWorkArticleView extends PoolCounterWork {
2058
2059         /**
2060          * @var Article
2061          */
2062         private $mArticle;
2063
2064         function __construct( $article, $key, $useParserCache, $parserOptions ) {
2065                 parent::__construct( 'ArticleView', $key );
2066                 $this->mArticle = $article;
2067                 $this->cacheable = $useParserCache;
2068                 $this->parserOptions = $parserOptions;
2069         }
2070
2071         function doWork() {
2072                 return $this->mArticle->doViewParse();
2073         }
2074
2075         function getCachedWork() {
2076                 global $wgOut;
2077
2078                 $parserCache = ParserCache::singleton();
2079                 $this->mArticle->mParserOutput = $parserCache->get( $this->mArticle, $this->parserOptions );
2080
2081                 if ( $this->mArticle->mParserOutput !== false ) {
2082                         wfDebug( __METHOD__ . ": showing contents parsed by someone else\n" );
2083                         $wgOut->addParserOutput( $this->mArticle->mParserOutput );
2084                         # Ensure that UI elements requiring revision ID have
2085                         # the correct version information.
2086                         $wgOut->setRevisionId( $this->mArticle->getLatest() );
2087                         return true;
2088                 }
2089                 return false;
2090         }
2091
2092         function fallback() {
2093                 return $this->mArticle->tryDirtyCache();
2094         }
2095
2096         /**
2097          * @param  $status Status
2098          */
2099         function error( $status ) {
2100                 global $wgOut;
2101
2102                 $wgOut->clearHTML(); // for release() errors
2103                 $wgOut->enableClientCache( false );
2104                 $wgOut->setRobotPolicy( 'noindex,nofollow' );
2105
2106                 $errortext = $status->getWikiText( false, 'view-pool-error' );
2107                 $wgOut->addWikiText( '<div class="errorbox">' . $errortext . '</div>' );
2108
2109                 return false;
2110         }
2111 }